Saturday, August 31, 2019

Digital Fortress Chapter 71-75

Chapter 71 Tokugen Numataka lit his fourth cigar and kept pacing. He snatched up his phone and buzzed the main switchboard. â€Å"Any word yet on that phone number?† he demanded before the operator could speak. â€Å"Nothing yet, sir. It's taking a bit longer than expected-it came from a cellular.† A cellular, Numataka mused. Figures. Fortunately for the Japanese economy, the Americans had an insatiable appetite for electronic gadgets. â€Å"The boosting station,† the operator added, â€Å"is in the 202 area code. But we have no number yet.† â€Å"202? Where's that?† Where in the vast American expanse is this mysterious North Dakota hiding? â€Å"Somewhere near Washington, D. C., sir.† Numataka arched his eyebrows. â€Å"Call me as soon as you have a number.† Chapter 72 Susan Fletcher stumbled across the darkened Crypto floor toward Strathmore's catwalk. The commander's office was as far from Hale as Susan could get inside the locked complex. When Susan reached the top of the catwalk stairs, she found the commander's door hanging loosely, the electronic lock rendered ineffective by the power outage. She barged in. â€Å"Commander?† The only light inside was the glow of Strathmore's computer monitors. â€Å"Commander!† she called once again. â€Å"Commander!† Susan suddenly remembered that the commander was in the Sys-Sec lab. She turned circles in his empty office, the panic of her ordeal with Hale still in her blood. She had to get out of Crypto. Digital Fortress or no Digital Fortress, it was time to act-time to abort the TRANSLTR run and escape. She eyed Strathmore's glowing monitors then dashed to his desk. She fumbled with his keypad. Abort TRANSLTR! The task was simple now that she was on an authorized terminal. Susan called up the proper command window and typed: ABORT RUN Her finger hovered momentarily over the ENTER key. â€Å"Susan!† a voice barked from the doorway. Susan wheeled scared, fearing it was Hale. But it was not, it was Strathmore. He stood, pale and eerie in the electronic glow, his chest heaving. â€Å"What the hell's going on!† â€Å"Com†¦ mander!† Susan gasped. â€Å"Hale's in Node 3! He just attacked me!† â€Å"What? Impossible! Hale's locked down in-â€Å" â€Å"No, he's not! He's loose! We need security inhere now! I'm aborting TRANSLTR!† Susan reached for the keypad. â€Å"DON'T TOUCH THAT!† Strathmore lunged for the terminal and pulled Susan's hands away. Susan recoiled, stunned. She stared at the commander and for the second time that day did not recognize him. Susan felt suddenly alone. Strathmore saw the blood on Susan's shirt and immediately regretted his outburst. â€Å"Jesus, Susan. Are you okay?† She didn't respond. He wished he hadn't jumped on her unnecessarily. His nerves were frayed. He was juggling too much. There were things on his mind-things Susan Fletcher did not know about-things he had not told her and prayed he'd never have to. â€Å"I'm sorry,† he said softly. â€Å"Tell me what happened.† She turned away. â€Å"It doesn't matter. The blood's not mine. Just get me out of here.† â€Å"Are you hurt?† Strathmore put a hand on her shoulder. Susan recoiled. He dropped his hand and looked away. When he looked back at Susan's face, she seemed to be staring over his shoulder at something on the wall. There, in the darkness, a small keypad glowed full force. Strathmore followed her gaze and frowned. He'd hoped Susan wouldn't notice the glowing control panel. The illuminated keypad controlled his private elevator. Strathmore and his high-powered guests used it to come and go from Crypto without advertising the fact to the rest of the staff. The personal lift dropped down fifty feet below the Crypto dome and then moved laterally 109 yards through a reinforced underground tunnel to the sublevels of the main NSA complex. The elevator connecting Crypto to the NSA was powered from the main complex; it was on-line despite Crypto's power outage. Strathmore had known all along it was on-line, but even as Susan had been pounding on the main exit downstairs, he hadn't mentioned it. He could not afford to let Susan out-not yet. He wondered how much he'd have to tell her to make her want to stay. Susan pushed past Strathmore and raced to the back wall. She jabbed furiously at the illuminated buttons. â€Å"Please,† she begged. But the door did not open. â€Å"Susan,† Strathmore said quietly. â€Å"The lift takes a password.† â€Å"A password?† she repeated angrily. She glared at the controls. Below the main keypad was a second keypad-a smaller one, with tiny buttons. Each button was marked with a letter of the alphabet. Susan wheeled to him. â€Å"What is the password!† she demanded. Strathmore thought a moment and sighed heavily. â€Å"Susan, have a seat.† Susan looked as if she could hardly believe her ears. â€Å"Have a seat,† the commander repeated, his voice firm. â€Å"Let me out!† Susan shot an uneasy glance toward the commander's open office door. Strathmore eyed the panicked Susan Fletcher. Calmly he moved to his office door. He stepped out onto the landing and peered into the darkness. Hale was nowhere to be seen. The commander stepped back inside and pulled the door shut. Then he propped a chair in front to keep it closed, went to his desk, and removed something from a drawer. In the pale glow of the monitors Susan saw what he was holding. Her face went pale. It was a gun. Strathmore pulled two chairs into the middle of the room. He rotated them to face the closed office door. Then he sat. He lifted the glittering Beretta semi-automatic and aimed steadily at the slightly open door. After a moment he laid the gun back in his lap. He spoke solemnly. â€Å"Susan, we're safe here. We need to talk. If Greg Hale comes through that door†¦Ã¢â‚¬  He let it hang. Susan was speechless. Strathmore gazed at her in the dim light of his office. He patted the seat beside him. â€Å"Susan, sit. I have something to tell you.† She did not move. â€Å"When I'm done, â€Å"he said, â€Å"I'll give you the password to the elevator. You can decide whether to leave or not.† There was a long silence. In a daze, Susan moved across the office and sat next to Strathmore. â€Å"Susan,† he began, â€Å"I haven't been entirely honest with you.† Chapter 73 David Becker felt as if his face had been doused in turpentine and ignited. He rolled over on the floor and squinted through bleary tunnel vision at the girl halfway to the revolving doors. She was running in short, terrified bursts, dragging her duffel behind her across the tile. Becker tried to pull himself to his feet, but he could not. He was blinded by red-hot fire. She can't get away! He tried to call out, but there was no air in his lungs, only a sickening pain. â€Å"No!† He coughed. The sound barely left his lips. Becker knew the second she went through the door, she would disappear forever. He tried to call out again, but his throat was searing. The girl had almost reached the revolving door. Becker staggered to his feet, gasping for breath. He stumbled after her. The girl dashed into the first compartment of the revolving door, dragging her duffel behind her. Twenty yards back, Becker was staggering blindly toward the door. â€Å"Wait!† He gasped. â€Å"Wait!† The girl pushed furiously on the inside of the door. The door began to rotate, but then it jammed. The blonde wheeled in terror and saw her duffel snagged in the opening. She knelt and pulled furiously to free it. Becker fixed his bleary vision on the fabric protruding through the door. As he dove, the red corner of nylon protruding from the crack was all he could see. He flew toward it, arms outstretched. As David Becker fell toward the door, his hands only inches away, the fabric slipped into the crack and disappeared. His fingers clutched empty air as the door lurched into motion. The girl and the duffel tumbled into the street outside. â€Å"Megan!† Becker wailed as hit the floor. White-hot needles shot through the back of his eye sockets. His vision tunneled to nothing, and a new wave of nausea rolled in. His own voice echoed in the blackness. Megan! David Becker wasn't sure how long he'd been lying there before he became aware of the hum of fluorescent bulbs overhead. Everything else was still. Through the silence came a voice. Someone was calling. He tried to lift his head off the floor. The world was cockeyed, watery. Again the voice. He squinted down the concourse and saw a figure twenty yards away. â€Å"Mister?† Becker recognized the voice. It was the girl. She was standing at another entrance farther down the concourse, clutching her duffel to her chest. She looked more frightened now than she had before. â€Å"Mister?† she asked, her voice trembling. â€Å"I never told you my name. How come you know my name?† Chapter 74 Director Leland Fontaine was a mountain of a man, sixty-three years old, with a close-cropped military haircut and a rigid demeanor. His jet-black eyes were like coal when he was irritated, which was almost always. He'd risen through the ranks of the NSA through hard work, good planning, and the well-earned respect of his predecessors. He was the first African American director of the National Security Agency, but nobody ever mentioned the distinction; Fontaine's politics were decidedly color-blind, and his staff wisely followed suit. Fontaine had kept Midge and Brinkerhoff standing as he went through the silent ritual of making himself a mug of Guatemalan java. Then he'd settled at his desk, left them standing, and questioned them like schoolchildren in the principal's office. Midge did the talking-explaining the unusual series of events that led them to violate the sanctity of Fontaine's office. â€Å"A virus?† the director asked coldly. â€Å"You two think we've got a virus?† Brinkerhoff winced. â€Å"Yes, sir,† Midge snapped. â€Å"Because Strathmore bypassed Gauntlet?† Fontaine eyed the printout in front of him. â€Å"Yes,† she said. â€Å"And there's a file that hasn't broken in over twenty hours!† Fontaine frowned. â€Å"Or so your data says.† Midge was about to protest, but she held her tongue. Instead she went for the throat. â€Å"There's a blackout in Crypto.† Fontaine looked up, apparently surprised. Midge confirmed with a curt nod. â€Å"All power's down. Jabba thought maybe-â€Å" â€Å"You called Jabba?† â€Å"Yes, sir, I-â€Å" â€Å"Jabba?† Fontaine stood up, furious. â€Å"Why the hell didn't you call Strathmore?† â€Å"We did!† Midge defended. â€Å"He said everything was fine.† Fontaine stood, his chest heaving. â€Å"Then we have no reason to doubt him.† There was closure in his voice. He took a sip of coffee. â€Å"Now if you'll excuse me, I have work to do.† Midge's jaw dropped. â€Å"I beg your pardon?† Brinkerhoff was already headed for the door, but Midge was cemented in place. â€Å"I said good night, Ms. Milken,† Fontaine repeated. â€Å"You are excused.† â€Å"But-but sir,† she stammered, â€Å"I†¦ I have to protest. I think-â€Å" â€Å"You protest?† the director demanded. He set down his coffee. â€Å"I protest! I protest to your presence in my office. I protest to your insinuations that the deputy director of this agency is lying. I protest-â€Å" â€Å"We have a virus, sir! My instincts tell me-â€Å" â€Å"Well, your instincts are wrong, Ms. Milken! For once, they're wrong!† Midge stood fast. â€Å"But, sir! Commander Strathmore bypassed Gauntlet!† Fontaine strode toward her, barely controlling his anger. â€Å"That is his prerogative! I pay you to watch analysts and service employees-not spy on the deputy director! If it weren't for him we'd still be breaking codes with pencil and paper! Now leave me!† He turned to Brinkerhoff, who stood in the doorway colorless and trembling. â€Å"Both of you.† â€Å"With all due respect, sir,† Midge said. â€Å"I'd like to recommend we send a Sys-Sec team to Crypto just to ensure-â€Å" â€Å"We will do no such thing!† After a tense beat, Midge nodded. â€Å"Very well. Goodnight.† She turned and left. As she passed, Brinkerhoff could see in her eyes that she had no intention of letting this rest-not until her intuition was satisfied. Brinkerhoff gazed across the room at his boss, massive and seething behind his desk. This was not the director he knew. The director he knew was a stickler for detail, for neatly tied packages. He always encouraged his staff to examine and clarify any inconsistencies in daily procedure, no matter how minute. And yet here he was, asking them to turn their backs on a very bizarre series of coincidences. The director was obviously hiding something, but Brinkerhoff was paid to assist, not to question. Fontaine had proven over and over that he had everyone's best interests at heart; if assisting him now meant turning a blind eye, then so be it. Unfortunately, Midge was paid to question, and Brinkerhoff feared she was headed for Crypto to do just that. Time to get out the resumes, Brinkerhoff thought as he turned to the door. â€Å"Chad!† Fontaine barked, from behind him. Fontaine had seen the look in Midge's eyes when she left. â€Å"Don't let her out of this suite.† Brinkerhoff nodded and hustled after Midge. Fontaine sighed and put his head in his hands. His sable eyes were heavy. It had been a long, unexpected trip home. The past month had been one of great anticipation for Leland Fontaine. There were things happening right now at the NSA that would change history, and ironically, Director Fontaine had found out about them only by chance. Three months ago, Fontaine had gotten news that Commander Strathmore's wife was leaving him. He'd also heard reports that Strathmore was working absurd hours and seemed about to crack under the pressure. Despite differences of opinion with Strathmore on many issues, Fontaine had always held his deputy director in the highest esteem; Strathmore was a brilliant man, maybe the best the NSA had. At the same time, ever since the Skipjack fiasco, Strathmore had been under tremendous stress. It made Fontaine uneasy; the commander held a lot of keys around the NSA-and Fontaine had an agency to protect. Fontaine needed someone to keep tabs on the wavering Strathmore and make sure he was 100 percent-but it was not that simple. Strathmore was a proud and powerful man; Fontaine needed a way to check up on the commander without undermining his confidence or authority. Fontaine decided, out of respect for Strathmore, to do the job himself. He had an invisible tap installed on Commander Strathmore's Crypto account-his E-mail, his interoffice correspondence, his brainstorms, all of it. If Strathmore was going to crack, the director would see warning signs in his work. But instead of signs of a breakdown, Fontaine uncovered the ground work for one of the most incredible intelligence schemes he'd ever encountered. It was no wonder Strathmore was busting his ass; if he could pull this plan off, it would make up for the Skipjack fiasco a hundred times over. Fontaine had concluded Strathmore was fine, working at 110 percent-as sly, smart, and patriotic as ever. The best thing the director could do would be to stand clear and watch the commander work his magic. Strathmore had devised a plan†¦ a plan Fontaine had no intention of interrupting. Chapter 75 Strathmore fingered the Berretta in his lap. Even with the rage boiling in his blood, he was programmed to think clearly. The fact that Greg Hale had dared lay a finger on Susan Fletcher sickened him, but the fact that it was his own fault made him even sicker; Susan going into Node 3 had been his idea. Strathmore knew enough to compartmentalize his emotion-it could in no way affect his handling of Digital Fortress. He was the deputy director of the National Security Agency. And today his job was more critical than it had ever been. Strathmore slowed his breathing. â€Å"Susan.† His voice was efficient and unclouded. â€Å"Did you delete Hale's E-mail?† â€Å"No,† she said, confused. â€Å"Do you have the pass-key?† She shook her head. Strathmore frowned, chewing his lip. His mind was racing. He had a dilemma. He could easily enter his elevator password, and Susan would be gone. But he needed her there. He needed her help to find Hale's pass-key. Strathmore hadn't told her yet, but finding that pass-key was far more than a matter of academic interest-it was an absolute necessity. Strathmore suspected he could run Susan's nonconformity search and find the pass-key himself, but he'd already encountered problems running her tracer. He was not about to risk it again. â€Å"Susan.† He sighed resolutely. â€Å"I'd like you to help me find Hale's pass-key.† â€Å"What!† Susan stood up, her eyes wild. Strathmore fought off the urge to stand along with her. He knew a lot about negotiating-the position of power was always seated. He hoped she would follow suit. She did not. â€Å"Susan, sit down.† She ignored him. â€Å"Sit down.† It was an order. Susan remained standing. â€Å"Commander, if you've still got some burning desire to check out Tankado's algorithm, you can do it alone. I want out.† Strathmore hung his head and took a deep breath. It was clear she would need an explanation. She deserves one, he thought. Strathmore made his decision-Susan Fletcher would hear it all. He prayed he wasn't making a mistake. â€Å"Susan,† he began, â€Å"it wasn't supposed to come to this.† He ran his hand across his scalp. â€Å"There are some things I haven't told you. Sometimes a man in my position†¦Ã¢â‚¬  The commander wavered as if making a painful confession. â€Å"Sometimes a man in my position is forced to lie to the people he loves. Today was one of those days.† He eyed her sadly. â€Å"What I'm about to tell you, I never planned to have to say†¦ to you†¦ or to anyone.† Susan felt a chill. The commander had a deadly serious look on his face. There was obviously some aspect of his agenda to which she was not privy. Susan sat down. There was a long pause as Strathmore stared at the ceiling, gathering his thoughts. â€Å"Susan,† he finally said, his voice frail. â€Å"I have no family.† He returned his gaze to her. â€Å"I have no marriage to speak of. My life has been my love for this country. My life has been my work here at the NSA.† Susan listened in silence. â€Å"As you may have guessed,† he continued, â€Å"I planned to retire soon. But I wanted to retire with pride. I wanted to retire knowing that I'd truly made a difference.† â€Å"But you have made a difference,† Susan heard herself say. â€Å"You built TRANSLTR.† Strathmore didn't seem to hear. â€Å"Over the past few years, our work here at the NSA has gotten harder and harder. We've faced enemies I never imagined would challenge us. I'm talking about our own citizens. The lawyers, the civil rights fanatics, the EFF-they've all played a part, but it's more than that. It's the people. They've lost faith. They've become paranoid. They suddenly see us as the enemy. People like you and me, people who truly have the nation's best interests at heart, we find ourselves having to fight for our right to serve our country. We're no longer peacekeepers. We're eavesdroppers, peeping Toms, violators of people's rights.† Strathmore heaved a sigh. â€Å"Unfortunately, there are naive people in the world, people who can't imagine the horrors they'd face if we didn't intervene. I truly believe it's up to us to save them from their own ignorance.† Susan waited for his point. The commander stared wearily at the floor and then looked up. â€Å"Susan, hear me out,† he said, smiling tenderly at her. â€Å"You'll want to stop me, but hear me out. I've been decrypting Tankado's E-mail for about two months now. As you can imagine, I was shocked when I first read his messages to North Dakota about an unbreakable algorithm called Digital Fortress. I didn't believe it was possible. But every time I intercepted anew message, Tankado sounded more and more convincing. When I read that he'd used mutation strings to write a rotating key-code, I realized he was light-years ahead of us; it was an approach no one here had never tried.† â€Å"Why would we?† Susan asked. â€Å"It barely makes sense.† Strathmore stood up and started pacing, keeping one eye on the door. â€Å"A few weeks ago, when I heard about the Digital Fortress auction, I finally accepted the fact that Tankado was serious. I knew if he sold his algorithm to a Japanese software company, we were sunk, so I tried to think of any way I could stop him. I considered having him killed, but with all the publicity surrounding the algorithm and all his recent claims about TRANSLTR, we would be prime suspects. That's when it dawned on me.† He turned to Susan. â€Å"I realized that Digital Fortress should not be stopped.† Susan stared at him, apparently lost. Strathmore went on. â€Å"I suddenly saw Digital Fortress as the opportunity of a lifetime. It hit me that with a few changes, Digital Fortress could work for us instead of against us.† Susan had never heard anything so absurd. Digital Fortress was an unbreakable algorithm; it would destroy them. â€Å"If,† Strathmore continued, â€Å"if I could just make a small modification in the algorithm†¦ before it was released†¦Ã¢â‚¬  He gave her a cunning glint of the eye. It took only an instant. Strathmore saw the amazement register in Susan's eyes. He excitedly explained his plan. â€Å"If I could get the pass-key, I could unlock our copy of Digital Fortress and insert a modification.† â€Å"A back door,† Susan said, forgetting the Commander had ever lied to her. She felt a surge of anticipation. â€Å"Just like Skipjack.† Strathmore nodded. â€Å"Then we could replace Tankado's give-away file on the Internet with our altered version. Because Digital Fortress is a Japanese algorithm, no one will ever suspect the NSA had any part in it. All we have to do is make the switch.† Susan realized the plan was beyond ingenious. It was pure†¦ Strathmore. He planned to facilitate the release of an algorithm the NSA could break! â€Å"Full access,† Strathmore said. â€Å"Digital Fortress will become the encryption standard overnight.† â€Å"Overnight?† Susan said. â€Å"How do you figure that? Even if Digital Fortress becomes available everywhere for free, most computer users will stick with their old algorithms for convenience. Why would they switch to Digital Fortress?† Strathmore smiled. â€Å"Simple. We have a security leak. The whole world finds out about TRANSLTR.† Susan's jaw dropped. â€Å"Quite simply, Susan, we let the truth hit the street. We tell the world that the NSA has a computer that can break every algorithm except Digital Fortress.† Susan was amazed. â€Å"So everyone jumps ship to Digital Fortress†¦ not knowing we can break it!† Strathmore nodded. â€Å"Exactly.† There was a long silence. â€Å"I'm sorry I lied to you. Trying to rewrite Digital Fortress is a pretty big play, I didn't want you involved.† â€Å"I†¦ understand,† she replied slowly, still reeling from the brilliance of it all. â€Å"You're not a bad liar.† Strathmore chuckled. â€Å"Years of practice. Lying was the only way to keep you out of the loop.† Susan nodded. â€Å"And how big a loop is it?† â€Å"You're looking at it.† Susan smiled for the first time in an hour. â€Å"I was afraid you'd say that.† He shrugged. â€Å"Once Digital Fortress is in place, I'll brief the director.† Susan was impressed. Strathmore's plan was a global intelligence coup the magnitude of which had never before been imagined. And he'd attempted it single-handedly. It looked like he might pull it off too. The pass-key was downstairs. Tankado was dead. Tankado's partner had been located. Susan paused. Tankado is dead. That seemed very convenient. She thought of all the lies that Strathmore had told her and felt a sudden chill. She looked uneasily at the commander. â€Å"Did you kill Ensei Tankado?† Strathmore looked surprised. He shook his head. â€Å"Of course not. There was no need to kill Tankado. In fact, I'd prefer he were alive. His death could cast suspicion on Digital Fortress. I wanted this switch to go as smoothly and inconspicuously as possible. The original plan was to make the switch and let Tankado sell his key.† Susan had to admit it made sense. Tankado would have no reason to suspect the algorithm on the Internet was not the original. Nobody had access to it except himself and North Dakota. Unless Tankado went back and studied the programming after it was released, he'd never know about the back door. He'd slaved over Digital Fortress for long enough that he'd probably never want to see the programming again. Susan let it all soak in. She suddenly understood the commander's need for privacy in Crypto. The task at hand was time-consuming and delicate-writing a concealed back door in a complex algorithm and making an undetected Internet switch. Concealment was of paramount importance. The simple suggestion that Digital Fortress was tainted could ruin the commander's plan. Only now did she fully grasp why he had decided to let TRANSLTR keep running. If Digital Fortress is going to be the NSA's new baby, Strathmore wanted to be sure it was unbreakable! â€Å"Still want out?† he asked. Susan looked up. Somehow sitting there in the dark with the great Trevor Strathmore, her fears were swept away. Rewriting Digital Fortress was a chance to make history-a chance to do incredible good-and Strathmore could use her help. Susan forced a reluctant smile. â€Å"What's our next move?† Strathmore beamed. He reached over and put a hand on her shoulder. â€Å"Thanks.† He smiled and then got down to business. â€Å"We'll go downstairs together.† He held up his Berretta. â€Å"You'll search Hale's terminal. I'll cover you.† Susan bristled at the thought of going downstairs. â€Å"Can't we wait for David to call with Tankado's copy?† Strathmore shook his head. â€Å"The sooner we make the switch, the better. We have no guarantees that David will even find the other copy. If by some fluke the ring falls into the wrong hands over there, I'd prefer we'd already made the algorithm switch. That way, whoever ends up with the key will download our version of the algorithm.† Strathmore fingered his gun and stood. â€Å"We need to go for Hale's key.† Susan fell silent. The commander had a point. They needed Hale's pass-key. And they needed it now. When Susan stood, her legs were jittery. She wished she'd hit Hale harder. She eyed Strathmore's weapon and suddenly felt queasy. â€Å"You'd actually shoot Greg Hale?† â€Å"No.† Strathmore frowned, striding to the door. â€Å"But let's hope he doesn't know that.†

Friday, August 30, 2019

Acl Reconstruction Graft Information

Graft report Patellar graft The patellar tendon bone-tendon-bone graft has been the â€Å"gold standard† graft choice for ACL reconstructions since it became common practice in the mid-1980. It has been used extensively by surgeons since that time and still remains the graft of choice for a high number of orthopedists who perform this surgery regularly. The patellar tendon graft has consistently demonstrated excellent surgical outcomes with a 90-95% success rate in terms of returning to pre-injury level of sports.A patellar tendon graft is harvested through a 3-4†³ long incision based just along the medial border of the tendon†¦ The middle third of the tendon 10-11 mm wide is then removed along with 2-2. 5 cm long bone blocks still apart of the tendon at each end of the graft from the tibial tubercle and the outer surface of the patella. This gives a composite bone-tendon-bone graft that has very strong insertion points of the tendon soft tissue into bone. The tensil e strength of this graft has been measured by Noyes (1984) to be about 2950 Newton’s to failure, versus the strength of an intact ACL at 2160 N.What happens to the remaining patellar tendon after a third of it has been removed? Over the course of three to four months after surgery the tendon regenerates or â€Å"grows back†. Initially it seems to overgrow into a thick, large tendon that then remodels back to a more normal contour by 12-18 months postoperatively. Surgeons have even been able to re-harvest another patellar tendon graft from the original tendon once enough time has passed for tendon reconstitution (although there's now evidence that this repaired tissue may not be as strong as normal patellar tendon tissue).Patellar tendon ruptures at the donor site are unlikely after the first few months post-op. Patellar tendon ruptures can and do occur however during the initial 6-8 weeks after surgery if the remaining tendon is stressed too hard. One of the advantages of this construct is that because the bone-tendon interface is quite strong, the surgeon only has to fix the block of bone in the bone tunnel rather than trying to fix the soft tissue itself.A headless screw is inserted next to the bone plug (like a square peg in a round hole) to interference fit and locks the bone in place. The patellar tendon fibers are thereby immediately secured and are stable enough to begin motion and weight bearing when tolerated. The ends of the graft heal bone-to-bone in around 6-8 weeks, which appears to be quicker than the healing process for soft tissue-to-bone. Interference screws are now available in a bioresorbable material that actually dissolves within the bone over 2 to 3 years.The â€Å"gold standard† graft isn't perfect, however. There may be more pain associated with this donor site than from any of the other graft choices. As a result there is sometimes a greater initial atrophy or wasting response of the quadriceps muscle compared to s ay either a hamstring or cadaver allograft. This can require more prolonged physical therapy to recover from and could possibly delay the initial return to sports. The incision (scar) is bigger, and almost all patients end up with a permanent loss of sensation 2-3†³ in size just lateral to the incision.There is a risk of patellar tendon ruptures, as well as fracturing the patella both intraoperative as well as postoperatively, although bone grafting the defect in the patella at the time of surgery has reduced the incidence of the latter. Patients who kneel a lot for a living are often unhappy with the patellar tenderness and sensitivity that can occur at the incision site and should probably consider an alternative graft choice. One of the bigger issues with patellar tendon grafts that recently has a number of orthopedists switching to alternative grafts is the incidence of anterior knee pain when patients try to resume athletic activities.Specifically there are some studies5 s howing an increased rate of patellofemoral pain and/or tendonitis of the patellar tendon with stairs, jumping, skiing and other such activities 6-12 months out from surgery. Ultimately these are often treatable with continued strengthening, rest from sports, and time, but these symptoms can delay the expected time of return to sports. In summary, the patellar tendon BTB graft is a safe and effective option for ACL reconstruction. It has a consistently successful clinical track record at all levels of athletic activity with excellent outcomes and reproducible results.Its major disadvantages are primarily increased tenderness kneeling on the donor incision site, and the possible risk of problems with patellar and patellar tendon pain upon initial return to sports. Semitendinosus Semitendinosus grafts are made with the semitendinosus tendon either alone, or accompanied by the gracilis tendon for a stronger graft. The semitendinosus is an accessory hamstring (the primary hamstrings are left intact), and the gracilis is actually not a hamstring, but an accessory adductor (the primary adductors are left intact as well).The two tendons are commonly combined and referred to as a four strand hamstring graft, made by a long piece. which is removed from each tendon. The tendon segments are folded and braided together to form a quadruple thickness strand for the replacement graft. The braided segment is threaded through the heads of tibia and femur and its ends fixated with screws on the opposite sides of the two bones. Hamstring grafts require a smaller incision and are usually less painful to harvest.Thus the initial postoperative period is often easier and more comfortable with this graft choice. Similarly, because there is no violation of the patellar tendon, there seem to be fewer problems with knee pain during the first few months that a patient is allowed to return to sports. The hamstring incision is away from the patella so patients are usually comfortable kneeli ng after their reconstruction. Because the quadriceps extensor mechanism isn't violated with a hamstring harvest there is often less initial quadriceps atrophy.With a quicker return of knee quadriceps strength some surgeons are allowing their fully recovered patients to return to sports a month or two earlier than they might for a patellar tendon BTB graft.. However there have not been any scientific studies examining the tensile strength to failure of a human ACL graft at three months after implantation that would support this approach. Certainly the animal research done on patellar tendon tensile strength in rhesus monkeys suggested that the graft was actually weakest at 3 months out before maturing at 6 months post-surgery.However the truth is that soft tissue-to-bone healing occurs at a slower rate than bone-to-bone healing. A number of surgeons are concerned that this fact is being ignored when patients are placed into an accelerated rehab without allowing extra time for the gr aft ends to begin to heal to the bone tunnels another disadvantage of hamstring tendon grafts is that harvesting them is a technically demanding procedure that requires considerable surgical experience. Pitfalls such as transecting (cutting in half) a tendon or injuring nerves or ligaments in the area of dissection are possible during the stripping process.There is also a different technique for tensioning the hamstring tendon in the knee once the femoral end has been secured. The graft needs to be pre-tensioned and it's important that each of the four graft ends be individually tensioned during the tibial fixation for best results. Allographs Another alternative available however is to use tissue from a cadaver that is called an allograft. Patellar tendon, hamstring tendon, and even Achilles tendon allografts can be used as ACL graft tissues and are inserted and fixed with the same techniques that are used for autografts.The advantages of using cadaver graft tissue are obvious; no risks, pain, or scars from the donor site. Surgical time is quicker and because there is considerably less discomfort postoperatively, the incidence of joint stiffness and atrophy of the quadriceps muscle is significantly reduced. Allografts are a good choice when there are limitations in a patient's own tissue availability. Complicated multiple ligament reconstructions needing several grafts routinely require the use of allograft tissue in addition to an autograft.Revision ACL reconstructions where an autograft has already been harvested are also an indication for using a cadaver grafts.. The biggest concern with using allografts is the risk of contracting a serious infection from the cadaveric tissue. Hepatitis and HIV can be transmitted through these tissues with potentially fatal outcomes. Bacterial infections are also a possibility and although not usually life threatening, can result in loss of the graft and cause subsequent arthritis. The dilemma with allografts is that they can't be 100% sterilized without altering or even destroying the tensile strength of the graft tissue.Imagine what happens to any food that is pressure-cooked at temperatures over 270 ° F under pressure for 10 minutes and you'll understand what happens to a patellar tendon graft sterilized in an autoclave. Similarly, radiating grafts with high enough doses to kill viruses has been shown to alter the collagen tissue and reduce the graft's tensile strength. Currently the preferred allograft treatment technique is a fresh frozen graft; the tissue is harvested, cleaned and then frozen in liquid nitrogen.The cadaver is screened extensively with hepatitis and HIV testing as well as a life style analysis to identify any high-risk behavior for these illnesses. Blood tests for HIV, however, are not infallible because they can lag 6 months between the time of infection and the conversion to a positive test. Nevertheless, the process is fairly safe and the published rate of contracting HIV f rom these tissue allografts is between 1 in 1. 2 to 2 million. There are some graft procurement companies who are able to do actual direct HIV viral testing on their tissues which lowers the risks even more.And several companies have developed proprietary cleaning techniques that they claim can guarantee sterility of their graft tissues. Some grafts are also treated with low dose irradiation (1-2 Mrads) in a compromise attempt to provide some degree of sterilization without damaging the tissue characteristics. Unfortunately there are some studies indicating that ACL reconstructions using these tissues may stretch out over time so non-irradiated grafts would be the ideal structural choice if infection were not a concern.Unlike organ transplants, allografts aren't usually at risk for tissue rejection by the host. This is because there's very little protein antigen in these washed grafts (the bone ends are completely cleansed of any marrow elements). The majority of the grafts are prim arily made up of collagen, which has very low antigenicity. Laboratory studies have shown that there is universally a low grade immune reaction to insertion of these foreign tissues, but this doesn't appear to be clinically significant in terms of achieving a successful outcome.Bone tunnel widening is sometimes seen with the use of allografts, but similar to the case of hamstring grafts, doesn't seem to have any significance in terms of functional problems. There are some early studies suggesting that allografts take longer to heal in the knee than comparable autograft tissue. At the same time the patient is recovering from the surgery quicker because of the reduced pain and morbidity of not having donated their own graft tissue. Typically allograft patients will feel like they're ready to get back into sports in just 3 or 4 months since their full strength and joint mobility are often achieved at that point.The combination of delayed allograft incorporation with an accelerated reco very can obviously spell disaster in terms of the ACL graft stretching or rupturing altogether. So patients with allografts must completely understand the healing process and comply with the temporary restrictions even though they may think their bodies are telling them it's OK to be doing more athletically. It takes a lot of mental discipline. And obviously it's a misconception that an athlete can return to sports earlier using an allograft in view of the above. The last disadvantage of allografts relates to the practical issues of cost and availability.There has been a national shortage of patellar tendon allografts due to increasing demand combined a low supply of suitably qualified cadavers. This shortage has been created in part by physicians who routinely use allografts as their first choice for ACL reconstruction grafts in spite of the fact that autograft tissues work wonderfully. Other cadaveric tissues such as hamstrings, Achilles tendons, and even anterior tibialis and pos terior tibialis tendons (some of the ankle tendons) are often being used instead of patellar tendons due to this availability issue.Some surgeons simply don't have ready access to the facilities that procure and process allografts. And allografts are expensive, running anywhere from $2000 to $10,000 depending on the tissue type and your geographic location My Choice If I needed to go into surgery for an ACL reconstruction surgery and I had to choose from one of these graft options, I would choose to go with the semitendinosus graft. I would shy away from the allograft mainly because I am uncomfortable with the whole idea of donor replacements being implanted in my body.Along with the great threat of infection the allograft also tends to be hard to obtain with a nationwide shortage of acceptable cadavers, therefore making them very expensive. When comparing the patellar graft and the semitendinosus graft its hard to find much of a difference in the results, both offer good knee stabi lity with minimal adverse effects after surgery. However, the semitendinosus graft affects a much different and less major tendon group, in return providing less knee related problems after surgery therefore giving it the advantage over the patellar graft in my eyes.

Policy Speech on Drug Abuse Essay

Some of you may remember back in 5th grade the D.A.R.E song. You know the song about staying away from drugs and making your own choices. Come on! It had little dance moves that went along with the words. Well if you don’t remember, heres an example of the Chapman Elementary school in Dublin Ohio singing at their D.A.R.E graduation. (play video) Who went through a program like this in their elementary school? According to the Ocean Shore Police, today D.A.R.E. is being taught in all 50 states, in more than 300,000 classrooms. However, this program is not as effective as it was originally sought out to be. Drug abuse is a tremendous problem that must be addressed by the community in order to aid in future prevention. Today I will be talking to you about the D.A.R.E program now and how it is slowly losing its popularity, my proposal on how to change it and how this will positively effect the younger generations. D.A.R.E, standing for Drug Abuse Resistance Education Program, was founded in 1983 by the Los Angeles Police Department and eventually spread across the country. DARE is a primary, or universal prevention program. It targets children and youth before or around the age of experimentation, usually 5th graders. Today, the program reaches more than 26 million children every year in the United States. The non-profit program uses trained law enforcement officers to teach students about drug and alcohol resistance and prevention, and making good life choices. The hour-long classes typically run 10 to 17 weeks, depending on the school. The D.A.R.E. program enables students to interact with police officers or sheriffs in a safe and controlled classroom environment. This helps students and officers meet and understand each other in a friendly manner. Since it was founded, D.A.R.E. has expanded to encompass programs for middle and high school students, conflict resolution, gang prevention, parent education, and after-school recreation and learning. The curriculum has also been revised over the years as a result of research findings and is now more interactive by promoting participation by students. D.A.R.E. has also  established a Scientific Advisory Board to aid in self- evaluation and recommend program changes. Kathi Ackerman, director of Minnesota DARE said, â€Å"Its curriculum has been revamped at least 10 times since its creation.† Still, many districts have had to cut the program because it was too expensive and the outcome did not meet their standards. Julie Olson, director of elementary education said that the Rosemount-Apple Valley district had to drop DARE due to their $15 million budget shortfall. The district used the program for two decades; however it was cut from 18 elementary schools, saving the district $50,000 annually. Although the program has said it involves middle and high school students, research found that 80% of primary school students had experienced some D.A.R.E. education, but only 20% of middle school students and 10% of high school students were exposed to any follow-up drug use prevention. This is one of the great weaknesses within the program. Without a follow up lesson, kids tend to forget what they learned or simply think it does not apply to them anymore. Regardless of the positives DARE teaches, being exposed to these lessons in only one grade is not enough for it to become a way of life. If we ask the question, does DARE help support healthy attitudes about drug use, increase knowledge and awareness of addiction, and increase skills important for youth to have, then the answer is without a doubt yes. However is this enough for our children? Their lives are at stake and if we do not see results, then we are not effectively doing our job. What the critics fail to recognize, is that no single program can be expected to have a lasting effect by itself. Namely, no one component in prevention is sufficient in and of itself to reduce the prevalence of drug use. For this reason, I propose an updated version of the DARE program. A version that will run throughout middle and high school, involve the parents, schools teachers, faculty and staff. This new program will continue on with all that is already in the DARE program; however, it will also include guest speakers, field trips and hands on activities. Volunteer guest speakers will range from previously abusive drug and alcohol users, current abusers and families of those that have lost a loved one to the disease of addiction. The lack of shock and â€Å"in your face† types of actions are what the current DARE program is missing. This may be due to the fact that its primary age  group for students is in the elementary school level. Kids in middle and high school need to see these types of people for it to actually effect them. I know that every teenager thinks they are invincible and that they can do anything. They have the mindset, â€Å"That could never be me.† I did, but boy did I get a news flash when I went on a field trip with my criminal justice class to the Nassau Jail. A few of the inmates volunteered to tell their stories. There was this one beautiful girl sitting in the corner and I honestly thought she was part of staff, until she stood up and told her story about drug addiction. She happened to live in my town. How crazy is that? That definitely hit home to many of the students in my class. This is the type of shock value we need to express to our children for them to understand the actual reality that ones actions can lead to. We can throw all of these stories onto a child or teenager, yet it cannot stop there. Parents who play a vital role in a child’s life, have to impose their influence on decision making to lead towards healthy choices. Within the program there will be parent and teacher seminars which will explain what the children are learning, the ways they are being taught and ways the adults can reenforce the lessons. The seminars for adults will also include the same guest speakers and opportunities to take the same field trips that the children go on. Finally these seminars will include how to detect signs of addiction, ways to sufficiently help your child and contact information for specialized therapists, rehabilitation centers and anonymous support groups. Some may see this as to be a bit heavy and too much for their children ages 10-18 to go through; however this is the harsh reality. We need to take action and take action now! Drug abuse is still a popular fad amongst teenagers even with prevention programs like DARE. Obviously, we as a community are not effectively doing our jobs. With a revised version of DARE, students, parents and teachers will be able to work together to prevent this fad from reoccurring. Having hands on activities, guest speakers, field trips and adult seminars will create a more sufficient program to lead children towards a healthy future. Now think back to the DARE song that Chapman Elementary School performed. Can we only teach our children a cute song or can we actually send a message  that will stick?

Thursday, August 29, 2019

Parking Problem At Florida State University Essay

Parking Problem At Florida State University - Essay Example By Improving the potential circulation and movement of these pathways and also eliminating various pathways which make the procedure cumbersome for pedestrians, will certainly improve the overall process. It is also evident that landscaping, protected walkways, and pathways and also adequate lighting facilities will help in enhancing the overall pedestrian experience and will improve the parking facilities. Students having bicycles or motorbikes will also be facilitated if the bicycle paths are made. An important thing to note, however, is that a bike path may not be highly convenient or effective if it is inconsistent with its procedures. According to Lyons, a bike pathway which can only create lanes of roadways which can merely switch to a sidewalk will merely create problems for potential riders and will also create conflicts and other problems for the pedestrians. By evaluating and analyzing these highly important procedures, Florida University would certainly have a concrete vie w of where we can focus on our efforts as well as all our technical resources. But, the higher authorities of this institute could be blamed for the occurrence or potential occurrence of such administrative shortages. The core requirement in this regard is the creation of a mutual alliance between teachers, students, school administrative authorities and all other stakeholders involved. The higher authorities in the university have to understand how essential a spacious parking space would be for students and other school staff.

Wednesday, August 28, 2019

Budgets Research Paper Example | Topics and Well Written Essays - 1000 words

Budgets - Research Paper Example According to its mission, PepsiCo is a company in the consumer products business (PepsiCo, 2009). It focuses on manufacturing and distributing convenient foods and beverages. Its products include Pepsi Cola and other soft drink brands, Frito Lay, Tropicana, Quaker and Gatorade (PepsiCo, 2009). The types of budget that will be used by any company should conform to the main business of the said company. In PepsiCo’s case, being a company in the food and beverage industry, its budgets should be tailored to its specific needs and targets. The first recommended budget is the advertising budget. Since PepsiCo produces consumer products, these products should be marketed to the widest range of potential customers as much as possible. To do this, PepsiCo needs to aggressively advertise its products and even how it positions its products. Such a move will cost a lot of advertising expenses for PepsiCo, expenses that should be estimated or projected and placed in an advertising budget. This advertising budget includes how much PepsiCo expects to spend in advertising over a period of time (usually within one year) in various advertising vehicles such as print, media and even online. The second recommended budget is the department budget, which is usually prepared on an annual basis, but with a monthly breakdown. This type of budget is prepared for a company that has â€Å"multiple sales revenue units† (Jagels and Ralston, 2006, p. 370). Since PepsiCo has different product lines, the company can treat each product line as a department and draw up a budget specific to that product line. Since the department budget will show the revenues and expenses for the given product line, PepsiCo can immediately analyze which product line is the most profitable for the company, which has a positive contribution to the company’s bottom line and which products need to

Tuesday, August 27, 2019

Early Childhood-Practical Life Research Paper Example | Topics and Well Written Essays - 750 words

Early Childhood-Practical Life - Research Paper Example When children are exposed to practical life activities early on in life it not only enables them perform common physical tasks but also helps in the character building as they learn patience and responsibility while performing the activities. For example practical life activities help children to button their shirts and tie their laces, to clean things, to set the table and eat properly and later clean and wash dishes and keep them in their respective places. All these tasks require patience and concentration and in the end give the child fulfillment and happiness upon completing the tasks. Children also learn to be devoted and accurate by doing the tasks and in the process they also develop and calm and dignified attitude. According to Maria, when a child is repeatedly exposed to real life tasks the child would automatically attain the ability to perform other tasks later in life. Performing everyday tasks would also enable the child to develop a sense of balance and analyze their movements. And when they repeat the tasks they would be able to achieve perfection in their tasks. The usefulness of repetition is especially true among young children and it also teaches the child a lifelong lesson to strive in achieving perfection in all their endeavors. 2. Achieving power over your own movements leads to independence. Montessori constantly refers to the importance of movement. A teacher can become an â€Å"obstacle to a child†. What did Maria Montessori mean by this statement? Taking the example of the teacher who prevented the little boy from viewing the objects in the basin through his own efforts, Maria stresses that it is necessary for instructors to initially watch the movements of their children and teach them the difference between what is right and wrong. This would help the children to better regulate their movements. Once the children are made aware of this

Monday, August 26, 2019

Diversity and the Culture of 'Fitting In' Essay

Diversity and the Culture of 'Fitting In' - Essay Example Two authors, Kenji Yoshino and Kwame Appiah, have recently addressed the problems confronting the diverse world of globalization. While they both advocate the justice and fairness that is due all people, they also have their differences. Yoshino warns that in the attempt to legislate equality, we have institutionalized conformity. In doing so we lose the very characteristics that make us unique. Appiah contends that as human beings we all possess cosmopolitanism, a worldly sense of shared ideals, principles, and moral obligations to our fellow man. From Appiah's point of view, we are more alike than different. Yoshino contends that our differences mark out individuality. Whose school is it anyway Students may wish to be cosmopolitan, and to shrink from their own uniqueness and just try to do their best at fitting in. Yoshino argues that it is the student's responsibility to bring to the experience their own individual outlook, flavor, and thinking. After all, it is the student's scho ol. Yoshino will help the student understand the implications of their culture, while Appiah will aid the student as they evolve from classroom to worldly college graduate. One of the most difficult tasks for any human being is the challenge of staying true to one's self, while fitting in with a diverse crowd. In college, this will be magnified several times over in every situation. We may be tempted to keep our true identity covered, out of fear of discrimination and bias. However, this would not only be unfair to yourself, but it would also cheat the other students out of the chance to experience the real you. We expect it of others and others expect it from us. Appiah speaks to this when he writes, "a deeper answer is that evaluating stories together is one of the central human ways of learning to align our responses to the world. And that alignment of responses is, in turn, one of the ways we maintain the social fabric, the texture of our relationships (29). We search for the common threads that bind us and as we work to build a world of universal civility based on the understanding of our sameness and an acceptance of our differences. We do not be come the same; we merely bring out and celebrate that which is the same. This celebration of the freedom to be unique is one of the ways in which we are all alike. "In practice, I expect the liberty paradigm to protect the authentic self better than the equality paradigm" (Yoshino 191). Women should not strive to be equal to be men, but should have as their goal the freedom and liberty to be women. Being free to be yourself, and not just fit in, in any social setting is the liberty that is the challenge for the college student. When you are free to be your true self, the classroom will present greater opportunities for self-expression and a deeper understanding of the material that is presented. When you know where you stand and where you are going, it is easier to see the effects of culture, bias, and the partiality that is presented in the classroom debates about the past, current events, and future policy. When you look around the campus you will see the future policy makers, the administrators, and leaders that will shape the future. A thorough understanding of the impact of culture and its potential for bias will be invaluable in shaping and contributing to the debate. If we wish to make

Sunday, August 25, 2019

Reflection essay Example | Topics and Well Written Essays - 500 words - 6

Reflection - Essay Example ry to the popular belief that the Filipino Amerasian children live prosperous lives in the Philippines since the country does not have anti-American sentiment. Whether or not a country nurtures anti-American sentiment provides no guarantee that its citizens would not be discriminated against if they look like Americans. The Filipino Amerasian children are socially outcast as they are identified with their American lineage instead of the Filipino lineage. The government of the US assumes moral responsibility to help the Filipino Amerasian children and provide them with the opportunity to migrate to the US. This can be achieved by preferring them on immigration services. Realization of any plans made in this regard requires joint cooperation of the Filipino people, the local governments of the Philippines, and the government of the US. It is noteworthy that the problem is not addressed just by providing these children with a way to reach the US; these children also need to be linked to their biological American fathers which is another challenge after the children reach the US. In order for the children to sue their fathers for child support, they need to know their fathers. Enforcement of child support is a matter primarily taken care of by state. Unfortunately, most states do not enforce the child-support payments ordered by court effectively. This imparts the need for providing these children with the opportunity to pursue redress at the federal level. It is just as important to address the issue at the source as it is to address it at the level of effects. American soldiers are still stationed overseas. It is important to see what steps the government of the US has taken to ensure that such biracial children with lost American fathers are not born to another nation like they were born to the Filipinos. Either the government should place a ban on the American soldiers having sexual intercourse with the local people or prostitutes of the host countries and

Saturday, August 24, 2019

Sustainable Housing Dissertation Essay Example | Topics and Well Written Essays - 1000 words

Sustainable Housing Dissertation - Essay Example People in the United Kingdom have received many benefits from sustainable housing. The United Kingdom has developed numerous green and sustainable buildings. The paper first elaborates the concept of Green Home or Sustainable housing and the need for switching to sustainable housing is been discussed. The code of sustainable homes focuses on evaluating the homes in terms of the benchmark of Building Research Establishment’s Eco homes. Various types of sustainable constructions are mentioned in the research paper. Furthermore, the paper debates on various energy resources as well as material useful for sustainable constructions. Additionally, a discussion on the proper location for sustainable building, on the basis of different parameters, is included in the paper. There many types of sustainable housing mentioned in the paper. The paper offers specific examples of Eco friendly constructions in United Kingdom. On the basis of this discussion the paper concludes that the well-b eing of future generation should be taken into consideration by the construction industry. Key words: sustainable housing, low or zero carbon houses, eco homes, carbon emission. TABLE OF CONTENT Page No. Abstract....................

Friday, August 23, 2019

Extra credit Assignment Example | Topics and Well Written Essays - 250 words

Extra credit - Assignment Example This passage provides a picture of the reading plan by stating that it consists of previewing, reading, marking and reviewing. These steps are fundamental for a reader as they provide easier approach to the reading material by identification of the primary ideas of the book and determining how long one can to complete reading it (Textbook Reading Resource, 4). However, this passage accounts for the necessity of reading in a quiet and comfortable place. The reading should be in slots such as 20 pages in 50minutes. For the case of mapping, the reader can do it by applying two approaches namely the fishbone and branching. These two methods simplify complex maps into simpler material to comprehend. In addition, three alternatives to mapping can be applied in a bid to understand the mapping trends. They include outlines, flashcards and listing ort category (Textbook Reading Resource, 13). On equal measure, this passage suggests an easier way to read a textbook. The SQ3R is easier an efficient way for one to read and comprehend something complex to remember. The method involves reading the words not ideas or concepts (Textbook Reading Resource, 20). In conclusion, their passage provides an easy reading plan, which will make the readers read procedurally and be able to understand the contents. In addition, the SQ3R makes reading simpler and fascinating when reading complex materials. For the case of mapping, fishbone and branching approaches are fundamental in interpret ting the map

Thursday, August 22, 2019

Juvenile Focus Article Example | Topics and Well Written Essays - 500 words

Juvenile Focus - Article Example Among such programs and strategies, include a package on guiding discipline in schools released by the collaborations between the departments of Justice and Education. In another strategy, the country’s National Center for Mental Health and Juvenile Justice has developed a course on mental health and juvenile justice called the â€Å"Mental Health and Juvenile Justice Collaboration for Change,† which as the name suggests, involves collaboration between different stakeholders on various juvenile issues. Overall, the author advances the important role that all stakeholders should play by collaborating with each other to address juvenile delinquency. Realizing that addressing juvenile delinquency requires the collaboration of all stakeholders from individual families to communities and to different government agencies, the author provides rationale for collaboration between different stakeholders, which makes the article important for anyone to read. By addressing issues on children and youths, the future of this country and the world, the article is important makes for an interested read for other people in order to acquaint themselves with the different approaches and the various ways they could get involved in the issue of juvenile delinquency. The article is easy to understand since the author uses simple language that is understandable without using jargon. In addition, the article is well organized as the author uses headings to present each item under discussion.

The sixth sense - review Essay Example for Free

The sixth sense review Essay I think that the sixth sense falls into a mystery-thriller. Mystery because at the start you wonder whats wrong with Cole, but half way though we find out his problem that he can see dead people, and then we wonder how he can be helped and will Malcolm be able to help him. Near the end there is an unexpected twist, and you find out Malcolm has been dead all along. The audience needs to believe that Malcolm has been dead all the time; otherwise we would know Cole could see dead people all along and most of the scenes would be pointless. Some bits of the film are scary and can make u jump, thats why it falls into a thriller. The film is meant to trick the audience all the way through with loads of twists and turns. The film could make people think maybe just for one second, are their dead people walking around that we cant see? And is there any one who could see dead people? At the beginning of the first scene it looks as if Coles mum and Malcolm have been having a conversation, because they are facing each other and appear to be looking at each other, we also think they have been having a conversation by the way they have been sitting, it looks like they have been sitting there for a while and they are nice and comfortable, but we actually dont see them talking. When Cole comes home Coles mum goes to great him, and they start to tell each other about there days that didnt really happen, like there dream days. While Cole and his mum talk about there dream day Malcolm smiles, this tell us that he knows what they said they did in there days arent true but its a nice thing to do, it also shows Cole and his mum have a good relationship. This scene is important for later on when Coles mum gets accused for beating him, this scene proves she would never hurt him and they have a good relationship. As Coles mum leaves the room she says you have got an hour this makes the audience assume that Malcolm and Cole have an hour to talk, but what she really means is Cole has an hour until dinner. The Camera helps deceive us because Coles mum turns around as she says, you have got an hour making it look like shes talking to Malcolm. After Coles mum leaves the room Cole and Malcolm play a game, Malcolm says its a mind reading game and if he reads Coles mind correctly Cole takes a step forward, but if he reads him mind wrong Cole takes a step back, if Cole get to the chair were Malcolm is sitting, he sits down and talks to Malcolm, but if he gets to the door he can go. We dont think anything unusual about Malcolm getting some of the questions about Cole right because he must know some background information about Cole as part of his job. We think Cole and Malcolms relationship is good and Malcolm is trying to build up Coles trusts with him, we think that have a normal Doctor client relationship. Cole says Malcolm is nice but he doesnt think Malcolm can help him, he says you cant help me Malcolm and Cole talk about Coles life at school, when his dad left and about Coles mum going to see someone like Malcolm but he didnt help her, and thats why Cole thinks Malcolm cant help him. Its important we think Cole and Malcolm have a normal Doctor client relationship so that we think Malcolm is a normal Doctor. We now know that Cole can see dead people because when hes in the hospital with Malcolm he says, I can see dead people. When Cole sees ghosts it is usually dark and it gets cold, it gets cold when the ghosts are angry, we no this because after the school play Cole says to Malcolm when they get mad it gets cold . When Cole talks to Malcolm it doesnt get cold and u cant see his breath, this shows that Malcolm is not angry and does not no hes dead, also if it got cold and we could see Coles breath when hes around Malcolm we would no Malcolm was dead half way threw, and we are not meant to find out until the end. At the begging of the restaurant scene we see Anna sitting down with her back to the camera, and Malcolm walking towards her threw the restaurant, then there is a close up on Malcolm standing right at the table looking directly at Anna, then he sits down and says Im sorry Anna she then looks straight ahead at him hes looking to his right as he talks, there is no eye contact, direct eye contact is made as the camera moves closer, Malcolm straight away after saying sorry to Anna starts talking about Cole, as the camera moves in they again avoid eye contact, there is a close up on Malcolm still talking to Anna about Cole. The camera pans round the weightier buts the cheque on the table, we see Anna and Malcolm both go to grab it Anna takes the cheque quickly making us think she is angry with Malcolm and doesnt want him to pay for it, as Anna signs the cheque the camera bends behind Malcolm, as it does so Malcolm apologises for the way he has been acting, Anna is mostly looking down signing the cheque and putting her things in her bag, as Malcolm is apologising Anna looks up making people think that she is agreeing with him, but she is really looking up because someone was laughing she looks down sadly again and says happy anniversary . During the whole scene we do not see them directly talking to each other and having a proper convocation. We think Anna is angry with Malcolm because he was late, and when he comes he just says sorry and then he starts talking about Cole, then he says sorry to her properly. As she leaves she says happy anniversary in a sarcastic way, this then means Malcolm forgot it was there anniversary what is another reason why Anna would be angry. This would make Anna think that she is second best and that her and Malcolm dont have a very good relationship. This scene adds to our belief that Malcolm is alive and not dead. We know Malcolm and Anna dont talk much because Malcolm is already dead. But the film leads us to believe that they dont talk much, because Anna is angry with Malcolm because Malcolm was late and Malcolm dont really no what to say, because he is an a difficult position. Anna doest really talk she just looks down at the ground making it look like she is angry. When Malcolm does talk he just starts talking about Cole and nothing else. The camera makes it look as if they are looking at each other, but theyre not because Anna cant see Malcolm. Anna sighs after Malcolm is finished talking, this makes up think that Anna is fed up and has had enough. The two scenes help our belief of Malcolm being alive because, it looks as if Malcolm is interacting with other people and other things, leaving the audience with no reason to doubt Malcolm being alive. It is important that we believe Malcolm is alive other wise, if we knew he was dead from the start most of the scenes would be pointless and would be boring for the audience. At the end of the film we realise Malcolm is dead when we see him talking to Anna, and all the deceptions Cole gave of dead people we see with Malcolm. We see flash backs of the two scenes and we realise that Malcolm never talked to anyone and that he didnt interact with anything, and the only person who could see and hear him is Cole.

Wednesday, August 21, 2019

Heavy Metal Accumulation Within Urban Regions of China

Heavy Metal Accumulation Within Urban Regions of China Word Count: 1944 Introduction The adverse health effects associated with heavy metal accumulation within the body are well documented with problems leading to cardiovascular, nervous system, blood and bone diseases. Heavy metals can be easily transferred to human bodies directly through inhalation, ingestion, and absorption from the skin. The predominant pathway of ingestion is through the soil-crop system due to the accumulation of heavy metals in agricultural areas. This is quite prevalent in rural areas of China as waste water is recycled to tend crops which provide the food for the urban population. Alongside wastewater irrigation, solid waste disposal and sludge applications; vehicular exhaust and industrial activities are the major sources of soil contamination with heavy metals, resulting in an increased metal uptake by the food crops grown on such contaminated soils (Khan et al. 2008). In the urban environment itself, a wide range of toxic substances can be released during recycling and disposal in indust rial processes which cause environmental damage and threaten public health. Heavy metals such as lead, cadmium, copper, zinc, and chromium are an important class of hazardous chemicals that can be released from out-dated industrial practices. Therefore a relationship exists with a high population density within China’s urban centres and heavy metal accumulation within the urban environments (soils, atmosphere and drinking water). Industry and economic activities are more concentrated in urban areas, and cities have become the geographic focus of resource consumption and chemical emissions, which cause many environmental problems (Luo et al. 2012). Heavy industries such as metal smelting, manufacturing, energy production, construction and the coal/fuel combustion techniques associated with the mentioned industries are usually localised within the urban centres of China. This is due to their close proximity to the large percentage of the urbanised population who commute to thei r workplaces, and also double up as consumers (and polluters). Because of this, industries release harmful pollutants as by-products into the atmosphere, or can infiltrate the drinking water, and/or affect soils within close proximity. Heavy metals in urban soils may come from various human activities such as vehicle exhaust, waste disposal, as well as coal and fuel combustion (Chen et al. 2005). A recent emergence is that of electronic waste recycling which is infamous for releasing heavy metals. Biophysical and Socioeconomic Background The cause for the environmental degradation which effects are now widely seen in China are by no means an issue that has sprung up overnight. Domestically, the modernisation drive of the Chinese government over the past 30 years has been the main contributor for the environmental degradation, in that the priority of urbanisation, industrialisation, and a stronger economy with the intent of increasing the standard of living for its citizens (reflected by higher consumption) has placed environmental concerns as inconsequential. Because of this, environmental policies over the past 30 years have been considerably lax or non-existent due to conflicting with economic targets. This deregulation by the environmental sector of the government has granted China unprecedented growth and surpass economic goals, but at great consequence to the environment with widespread pollution in all the major cities. Only recently has the Chinese government realised the magnitude of their actions on the envi ronment which have been revealed through recent studies. The first national soil pollution survey conducted between 2005 and 2013 by the Chinese government’s Environmental Protection Ministry showed that 16.1% of China’s soil and 19.4% of its arable land was contaminated with cadmium, nickel and arsenic (BBC, 2014). China’s rapid and extended period of industrial development with subsequent high pollutant emissions has left many regions with deteriorated land quality and soil pollution. Compared to the surveys conducted between 1986 and 1990, levels of inorganic materials were markedly higher. This has dire consequences for the food security of the Chinese people and both the global community, as China currently relies heavily on grain imports to satisfy the needs of its citizens. The Chinese government set the minimum arable land for food production just over 300 million acres, of which this recent study has shown their available arable land does not meet this minimum meaning that China lacks agricultural self-sufficiency (Pei, 2014). Reversal of the degradation is costly and generally avoided, thus the Chinese government is opting to invest in foreign land and agriculture. Many of the recent surveys and research conducted by the government has had loose affiliation with scientific bodies and subsequently distorted evidence with the intent to strengthen political and economic motives, while masking the true nature of the situation. As a result, initial conservative estimations made by the government are insufficient and by no means an accurate representation of the environmental issues facing China. Internationally, the demand for cheaper Chinese labour and consumables has only perpetuated and reinforced the economic drive and manufacturing capabilities of China over the past 30 years – with the environment suffering due to inadequate regulation, economic priorities and a lack of perception for wider issues such as environmental. Specifically, with the expansion of the global market and increased demand for electrical and electronic products (and their short lifespan), electronic waste has become one of the most rapidly growing problems pertaining to waste in the world. A great quantity of electronic waste originating from developed countries has been transferred to developing countries such as China, India, and some African countries where electronic waste is processed using less advanced technology. A wide range of toxic substances can be released during the recycling and disposal and cause environmental damage and threaten public health, especially those of heavy metal s (Zheng et al. 2013). Management Approaches in the Past It was in 1973 where the Chinese government held its first national conference on environmental protection. For the following 20 years, emphasis was placed on pollution control and prevention as the major cities faced industrial and pesticide pollution. Again in 1983 environmental protection was announced as one of the two basic state policies (the other being family planning, or notoriously known as the ‘one child policy’). However proper action to environmental impact has only occurred relatively recently (the mid to late 1990’s) marked by the issuing of the national strategy of sustainable development: ‘Ten strategic Policies for Environment and Development’ and in 1994 the publishing of ‘Agenda 21’. Subsequently, China has implemented a strategy of two fundamental transformations – the transition from a planned economic system to a socialistic market economic system (Wang 2010). Policies within the 1990’s focused mainly on point source control of pollution from industries, and heavily around catchment systems (due to the problem of contaminated water) in contrast to remediation of areas affected by pollution. As is still problematic today, government bodies responsible for the implementation are hindered by weak institutional capacities and generally lack experience in the new field of environmental management (Wang 2010) leading to confusion between local and central governments in relation to the arbitration of policies. Guidelines of environmental protection have been established through many separate rules and regulations authorised by different government entities at different phases adding to this disarray. Local governments also lacked the financial capacity to compensate residents in natural reserves causing conflict within the communities. Centralisation of this organisation appears to be an ongoing process. Similarly, it is all well and good announcing what is going to be done (albeit vag uely) but whether or not action is taken is another matter. Adding to this significance is that the Chinese government is both the regulator and polluter in many instances, and must realise this. Management Approaches at Present and for the Future Presently, the government has specific planned efforts to protect species and ecosystems and have greatly increased over the past decade, but effectiveness has not kept pace with degradation. Major problems exist such as low levels of staff training, inadequate funding and rampant commercial development. The central government’s large-scale payment for ecosystem services campaigns are remarkable in terms of funding and longevity but program effectiveness remains unclear due to a general lack of science based assessment and conflicting outcomes with positive results that meet program goals (Grumbine Xu 2013). The issue of heavy metal accumulation within soils (be it rural or urban) is not directly targeted with China’s environmental management plans of the future. Although management plans incorporate the cleaning up of industries and practices which will hopefully have flow down affects leading to the reduction of problematic pollution (namely, heavy metals). These new ly implemented, almost ‘ad hoc’ environmental standards may not be up to speed to match the ever increasing economic growth and continual urbanisation. Similarly, implementing policy is one thing, enforcing it is another. In rural areas, China did not begin to invest in water pollution control until 2008 with the Ministries of Environmental Protection and Agriculture expecting coverage of 10% of all villages by 2015. In 2012 and again in 2013, the State Council and Ministry of Environmental Protection issued new national policies and funding to strengthen water use and decrease pollution, but institutional reforms necessary for improved implementation have not been addressed (Grumbine Xu 2013). Reformation of current environmentally specific laws (water, biodiversity, conservation) and forging of legal management mandates between provinces and government bureaus within their specific areas, alongside encouraging more policy participation from citizens, non-government o rganisations and businesses is desirable. Some of these reforms go against current government norms, but international scholars believe that significant environmental degradation impacts (such as water scarcity or hazardous materials) will drive more cooperative institutional behaviour (Grumbine Xu 2013). There is little interdisciplinary framework to address the lack of policy connections within and across China’s social–ecological systems. At the national level, ministerial actions often lack coordination and officials often do not have the capacity to enforce regulations. There are disconnects between central and local decision making; at local levels, Beijing’s edicts are subject to behaviour where officials often act contrary to central government mandates resulting in poor policy implementation. With environmental problems now openly acknowledged but solutions still far off, and already-unprecedented urbanisation rates gaining speed. But there still are n o functional national-level regulations in place to guide the largest and most rapid urban expansion in world history (Grumbine Xu 2013). Conclusions and Recommendations After three decades of unconstrained economic growth, China’s social and ecological debts are coming due. The new Chinese leadership has a full agenda yet measured against broad adaptive capacity standards, thus the government remains weak at solving complex, cross-cutting problems. Experts are in agreement that open information exchange, government transparency, institutional coordination, public and private sector participation, iterative decision making and conflict resolution are critical to resolving environmental and social issues under 21st century conditions. These capacities may have little to do with supporting economic expansion under a command-and-control decision making system, but they are recommended repeatedly to solve governance problems in a world of decreasing resources and increasing uncertainty. China must realise that it is both the polluter and regulator so must mediate the two with particularly stronger enforcement of environmental concerns. Short term economic goals should not outweigh the long term importance of the environmental order. Soil is an important component of urban ecosystems, thus its quality must be recognised and integrated into environmental monitoring and management programs. Extensive investigations into urban soil contamination in China have been conducted in the last 25 years but prove inadequate. Given the importance of urban soils, future research should focus on making comprehensive assessments of urban soil quality for better city planning and the sustainable management of urban soil resources. Since metals and organic pollutants have been found many cities of China, these and other emerging contaminants should be included in a multi-compartmental environmental surveillance of urban areas. Biological indicators could be used such as plant, soil invertebrate and microbial assays leading to an improved assessment of soil quality than physico-chemical measurements alone. Attention should be paid towards semi- rural and peri-urban agriculture practices with potential to human health implications. In addition to routine urban soil surveys, a land use-based and environmental availability-based integrated risk assessment framework of pollutants for urban soils needs to be developed in China (Luo et al. 2012). References BBC news China, 18th April 2014, ‘Report: One fifth of China’s soil contaminated’ http://www.bbc.com/news/world-asia-china-27076645 Chen H, Zheng C, Tu C, Zhu Y, 1999, ‘Heavy metal pollution I soils in China: Status and countermeasures’, Ambio, Vol. 28, pp. 130-134 Chen TB, Zheng YM, Lei M, Huang ZC, Wu HT, Chen H, Fan KK, Yu K, Wu X and Tian QZ, 2005, ‘Assessment of heavy metal pollution in surface soils of urban parks in Beijing, China’, Chemosphere, Vol. 60, pp. 542-551 Grumbine RE Xu J, 2013, ‘Recalibrating China’s environmental policy: The next 10 years’, Biological Conservation, Vol. 166, pp. 287-292 Khan S, Cao Q, Zheng YM, Huang YZ and Zhu YG, 2008, ‘Heath risks of heavy metals in contaminated soils and food crops irrigated with wastewater in Beijing, China’, Environmental Pollution, Vol. 152, pp. 686-692 Luo X, Shen Y, Zhu Y, Li X, 2012, ‘Trace metal contamination in urban soils of China’, Science of the Total Environment, pp. 17-30 Pei M, 18th April 2014, ‘China’s soil pollution: It’s much worse than you think’, Fortune Magazine, http://fortune.com/2014/04/18/chinas-soil-pollution-its-much-worse-than-you-think/ Wang L, 2010, ‘The changes of China’s environmental policies in the latest 30 years’, Procedia Environmental Sciences, Vol. 2, pp. 1206-1212 Zheng J, Chen K, Yan X, Chen S, Hu G, Peng X, Yuan J, Mai B, Yang Z, 2013, ‘Heavy metals in food, house dust, and water from an e-waste recycling area in South China and the potential risk to human health’, Ecotoxicology and Environmental Safety, Vol. 96, pp. 205-212

Tuesday, August 20, 2019

Effects of Ultrasound Therapy on MCL Injuries

Effects of Ultrasound Therapy on MCL Injuries The medial collateral ligament (MCL) is one of the most frequently injured ligaments of the knee joint. Fortunately, most patients who sustain MCL injuries are able to achieve their previous level of activity without the need for surgical treatment. However, the most severe injuries, especially those involving multiple ligaments, may require operative repair. This study will explore the effectiveness of a conservative treatment, namely ultrasound therapy and exercise therapy, in the treatment of MCL injuries of the knee joint. In a review by Phisitkul, James, Wolf, and Amendola (2006), treatment with early range of motion (ROM) exercises and progressive strengthening has been shown to produce very good results. Ultrasound therapy has been a widely used and well-accepted physical therapy modality for musculoskeletal conditions for many years. Wong, Schumann, Townsend, and Phelps (2007) performed a survey about the use of ultrasound by physical therapists who are orthopaedic specialists, and found that ultrasound therapy is a popular adjunct in orthopaedic physical therapy and that it is perceived as important. However, the lack of studies confirming its benefits has led many to question this traditional view. Indeed, many studied which explored the effectiveness of ultrasound therapy failed in establishing a definite conclusion. Nevertheless, it cannot be assumed that this lack of evidence implies that ultrasound therapy is ineffective, and thus further research is needed to establish the adequacy of its use. This study aims at answering the following crucial questions: In patients with MCL injuries of the knee, can ultrasound improve pain, disability and general recovery? Is it more effective than exercise therapy in improving symptoms? An answer to these questions will help to better direct physiotherapy treatment for these patients, and thus optimize recovery. Subsequent chapters will discuss the current literature available on the subject, followed by the methodology used in this study. The results are then presented and analysed. The interpretation of results in the context of previous research will be discussed in the discussion chapter, including the strengths and limitation of the study. Literature Review Ultrasound therapy has become commonly used in soft tissue injuries (Speed, 2001). Research carried out in the past few decades regarding the effects of ultrasound on body tissues will be discussed below. My aim is to review the research available from the past years in attempt to find conclusive and consistent results regarding the effects of ultrasound, and thus to justify the use of ultrasound in the clinical setting, specifically to treatment of medial collateral ligament injuries. As will be discussed in this chapter, when ultrasound enters the body, it is thought to exert an effect on it through thermal and non-thermal mechanisms (Robertson, Ward, Low, Reed, 2006, p.266). Some of these effects may stimulate healing; however others may be dangerous and may cause damage. Thermal effects of ultrasound As ultrasound waves travel trough body tissues, they cause oscillation of particles, thus converting sonic energy into heat energy. The amount of heat produced will greatly depend upon the intensity given and the rate of energy absorption, but also on certain tissue properties, such as the heat capacity, efficiency of heat transfer, and the tissue distribution and space (Robertson, Ward, Low, Reed, 2006, p.266). Some authors have suggested pre-heating the area of treatment to achieve a greater increase in tissue temperature (Draper et al 1998a). Living tissue will be affected by an increase in temperature in various different ways. According to Speed (2001), the thermal effects of ultrasound include an increased extensibility in tissues, enhanced blood flow, pain modulation, decreased joint stiffness and muscle spasm, together with a mid inflammatory response. These could explain why a temporary increase in range of motion is observed after ultrasound treatment (Draper et al., 1998b; Knight et al., 2001). Hayes, Merrick, Sandrey and Cordova (2004) studied the extent of heating in tissue at 2.5cm depth and found that 3MHz ultrasound was more effective in heating the tissues at this depth than 1MHz, reaching a temperature of 40 degrees Celsius after 4 minutes. Unfortunately the production of heat may place the patient at risk of a skin burn if applied incorrectly (Robertson, Ward, Low, Reed, 2006, p.290). Physical effects of ultrasound Cavitation Cavitation is the formation of tiny gas bubbles in the tissues as a result of ultrasound vibration (Robertson, Ward, Low, Reed, 2006, p.267). Johns (2002) explains how as sound waves travel through the tissues, the characteristic compression and rarefaction causes microscopic gas bubbles present in the tissue fluid to contract and expand. Injury to the cell may occur when these gas bubbles expand and collapse rapidly. Nevertheless, cavitation has been found to occur only when using high intensities, and thus it is unlikely to occur in vivo with therapeutic levels (Nyborg, 2001). However according to a review by Baker, Robertson, and Duck (2001), there are a few studies which suggest the existence of in vivo cavitation. Baker and his colleagues argue that these studies were not replicated and that results obtained may have been due to difficulty with the analysis of B-scan imaging, which were used to measure cavitation. A recent study investigated the method by which cavitation is de tected. The wavelet approach was identified as a new tool for studying bubble cavitation (Zhou, 2008). Cavitation becomes clinically relevant during ultrasound applications in water, as bubbles that form between the skin and the treatment head may block transmission of ultrasonic waves (Ward Robertson, 1996). Acoustic streaming Acoustic streaming may be described as a flow of liquid caused by a generation of pressure along the axis of the beam of energy and on any other structures which reflect it (Robertson, Ward, Low, Reed, 2006, p.268). There are two types of acoustic streaming: microstreaming and bulk streaming (Duck, as cited in Baker, Robertson Duck, 2001). Bulk streaming occurs in any fluid and develops as the ultrasound beam is propagated, while microstreaming occurs at a microscopic level and is formed as eddies of flow flanking to an oscillating surface (Robertson, Ward, Low, Reed, 2006, p.268). Unfortunately bulk streaming is much less mechanically powerful, with microstreaming being the only type of acoustic streaming which is able to stimulate cell activity and change membrane permeability (Duck, as cited by Baker, Robertson, Duck, 2001). Microstreaming can produce stress on the cell membrane and wash away any molecules and ions which accumulate outside the cell membrane (Robertson, Ward, Low, Reed, 2006, p.268). According to Duck (as cited by Baker, Robertson, Duck, 2001), only bulk streaming occurs in vivo, because microstreaming only occurs secondary to cavitation. In vitro studies show increased growth factor production by macrophages (Young and Dyson, 1990a), increased calcium uptake (Mortimer and Dyson, 1988), increased secretion and degranulation of mast cell (Fyfe and Chahl, 1984) and increase cell membrane permeability (McCance and Huether, as cited by Baker, Robertson, Duck, 2001) by microstreaming. This however will have minimal relevance in the clinical se tting if one assumes that cavitation will not occur. Nevertheless, Manasseh, Tho, Ooi, Petkovic-Duran, and Zhu, (2010), suggest that microstreaming which occurs secondary to cavitation will play a role in the action of microbubbles in therapeutic ultrasound. Standing waves Standing waves are formed when reflected sound waves are superimposed with incident waves, and are characterized by high pressure peaks, the antinodes and zones of low pressure known as nodes (Robertson, Ward, Low, Reed, 2006, p.267-8). Ter Haar and Wyard (1978) put forward that blood cell stasis may occur with ultrasound, with cells forming at half wavelength intervals in the blood vessels at antinodes. These results match those by Dyson, Pond, Woodward, and Broadbent (1974). The latter studied the effect of a stationary wave on blood cell stasis and endothelial damage in blood vessels of chick embryos. The cells form bands half a wavelength apart inside blood vessels. They suggest that under optimum conditions, the minimum intensity of less than 0.5 Wcm-2 at 3 MHz with continuous irradiation is required for stasis to occur. Damage to some endothelial cells of vessels in which stasis has occurred was revealed by an electron microscope. Thus, it is suggested that the treatment head is continuously moved during the treatment to minimize the formation of standing waves (Robertson, Ward, Low, Reed, 2006, p.268). The effect of ultrasound on repair of body tissues According the following research, ultrasound therapy may have an effect on cells involved in repair of body tissues, including: Levels of prostaglandins and leukotrienes Leung, Ng, and Yip (2004) performed a randomized, case-control study to study the effect of ultrasound during the acute inflammation of soft-tissue injuries. They measured the levels of leukotriene B4 and prostaglandin E2 in the medial collateral ligament of rats and found that pulsed ultrasound (1:4) applied for five minutes at different durations and intensities may stimulate acute inflammation by increasing the levels of the above mentioned leukotriene and prostaglandin. Release of fibroblast from macrophages Young and Dyson (1990a) studied if ultrasound therapy can increase the release of fibroblast mitogenic factors from macrophages in vitro, and assessed fibroblast proliferation over five days. This study showed an increased secretion of already formed fibroblasts in macrophages at 0.75 MHz ultrasound, which may be caused by permeability changes. On the other hand, at 3 MHz frequency, ultrasound appeared to encourage both the synthesis and secretion of fibroblast mitogenic factors. The reason why these two frequencies cause different effects may be explained by the different physical mechanisms involved. Williams (as cited in Young, 2002, p. 217), argues that cavitation is more liable to occur at lower frequencies, while at a higher frequency heating is more likely. Platelets and ÃŽÂ ²-thromboglobulin Williams, Chater, Allen, Sherwood, and Sanderson (1978) investigated the effect of ultrasound on platelets and established that more ÃŽÂ ²-thromboglobulin, a platelet specific protein, was released by ultrasound therapy. They suggest that this protein is released both by the disruption of platelets by cavitation and by other aggregating agents liberated in parallel with it which cause a release reaction in the adjacent platelets. This however, has not been proved to happen in vivo. Histamine release from mast cells Fyfe and Chahl (1984) suggest that ultrasound applied in the therapeutic range causes a significant increase in degranulated mast cells and thus an increase in histamine release, in rats. They suggest the possibility that ultrasound increases the permeability of mast cells to calcium causing them to degranulate, resulting in an increase in local blood flow. On the other hand, when Hogan, Burke, and Franklin (1982) investigated the change in blood flow in rat muscle on insonation, they found that arterioles vasoconstrict transiently in response to insonation, but improve perfusion after long-term treatment. Increase membrane permeability to calcium Change in the permeability of membranes to calcium has been demonstrated when using therapeutic ultrasound. According to Al-Karmi, Dinno, Stoltz, Crum, and Matthews (1994), applying ultrasound for two minutes will cause a significant boost in ionic conductance in the presence of calcium ions, thus confirming that calcium ions influence the biological effects of ultrasound. Dinno et al. (1989) also used a frog skin model to study the effect of ultrasound on membranes. They argue that the increase in the concentration of calcium ions inside cells which occurs after the application of ultrasound, may decrease the permeability of gap junctions and uncouple cells in the way by which cells differentiate. Therefore, they concluded that ultrasound can affect cell differentiation and consequently histogenesis, and thus its use should be avoided over embryonic tissue. Growth factor secretion Ito, Azuma, Ohta, and Komoriva (2000) applied ultrasound to a co-culture system of human osteoblastic and endothelial cells and studied their effect on growth factor secretion. Their study showed that ultrasound increases the levels of platelet-derived growth factor. This may be the reason for improved fracture healing rate with ultrasound treatment, as discussed later. Fibroblasts and Collagen synthesis Ramirez, Schwane, McFarland, and Starcher (1997), conducted an investigation to determine the effect of ultrasound on the rate of cell proliferation and collagen synthesis by using cultured fibroblasts form the Achilles tendons of neonatal rats. They found an increase in collagen synthesis and rate of thymidine incorporation and DNA content after ultrasound treatment, suggesting that ultrasound stimulates the synthesis of collagen in tendon fibroblasts and cell division after injury. In a more recent study Chiu, Chen, Huang, and Wang (2009), studied the effect of ultrasound on the proliferation of human skin fibroblasts at different frequencies. They applied ultrasound for three minutes daily for three days and found an increase in fibroblast proliferation by both 1 and 3 MHz frequencies, with less stimulation when using 0.5 MHz frequency. Chiu et al., also took into account temperature changes and found a change of only one degree Celsius after insonation, thereby implying that the results observed where due to non-thermal effects. This can be explained by the increase in protein synthesis found to occur in fibroblasts after ultrasound treatment. Harvey, Dyson, Pond and Grahame (1975) suggest that therapeutic ultrasound at 3 MHz frequency and at an intensity of 0.5 2.0 Wcm-2, can directly stimulate protein synthesis in fibroblasts, without any other cells acting as mediators. In fact they attributed this to membrane-associated changes. Nevertheless, the increase in fibroblast proliferation may occur as a result of the effects of ultrasound on macrophages, which release fibroblasts mitogenic factors (Young Dyson, 1990a), as previously discussed. Ultrasound not only stimulates fibroblasts to produce more collagen (Ramirez et al. 1997), but the collagen produced also has a higher tensile strength and is better organized and aggregated. Okita et al. (2009) studied joint mobility and collagen fibril arrangement in the endomysium of immobilized rat soleus muscle, and showed that therapeutic ultrasound may prevent changes in joint mobility and collagen fibril movement which occur with immobility. In contrast, when Larsen, Kristensen, Thorlacius-Ussing and Oxlund (2005) studied the influence of pulsed ultrasound at 3 MHz frequency and different intensities, on the mechanical properties of healing tendons in rabbits, they found greater extensibility after insonation with higher intensities, however there was no significant change of the point of rupture when the tendons were loaded, suggesting that pulsed ultrasound did not improve the mechanical properties of the healing tendons. Angiogenesis Therapeutic ultrasound may also affect the rate of angiogenesis. Young and Dyson (1990b) considered the formation of new blood vessels in full-thickness lesions of flank skin in adult rats and found that by day 5 post-injury, ultrasound treated wounds had developed a greater number of blood vessels, and were thus at a more advanced stage in the repair process. However by the seventh day, there was no significant difference between the groups. Therapeutic mechanism On the basis of these conflicting results, two schools of thought were developed. The evidence-based or factual school considers heat as the only effect of ultrasound therapy and thus emphasise the use of high doses and give little value to low intensity and pulsed treatment. This view is found in most American writing about this subject. On the other hand, the other school of thought is largely European, and is more involved in the biological and mechanical effects of pulsed low-intensity treatments (Robertson, Ward, Low, Reed, 2006, p. 269). Robertson, Ward, Low, Reed, (2006, p. 269) suggest that clinical studies may be used to investigate which doses produce better outcomes. In vitro studies can provide a dose-response relationship which may provide information about the most effective dose. Nevertheless, effects demonstrated in vitro, such as cavitation and acoustic streaming have not yet been shown to occur in vivo, since it is difficult to produce doses in vivo which are comparable to dose in vitro. They argue that in vitro, ultrasound is applied to only a thin layer of cells, and thus the noted changes do not necessarily occur when applied to a much larger volume of tissue in vivo. Moreover, in vitro the energy is confined to a very small volume and thus the power density will be much higher than in vivo. Therapeutic effects of Ultrasound Ultrasound therapy has been claimed effective in a wide range of clinical conditions, however there are still difficulties in establishing the effectiveness of ultrasound with certainty and in identifying a dose-response relationship, if there is any. Some of the alleged effects of ultrasound include promotion of fracture healing, soft tissue healing, articular cartilage repair, pain relief, increase local blood flow, change the extensibility of scar tissue and for the diagnosis of a stress fracture, and will be discussed below. Fracture healing Ultrasound has been proposed to promote the processes involved in fracture healing and thus increase its rate. Sun et al., (2001) investigated the effects of low-intensity pulsed ultrasound on bone cells in vitro, and found a significant increase in osteoblast cell counts and a significant decrease in osteoclast cell count after stimulation, suggesting a positive effect on the bone-healing process. Nolte et al., (2001) also studied the in vitro effects of low intensity ultrasound. The latter used foetal mouse metatarsal rudiments and found an increase in length of the calcified diaphysis, which was significantly greater in the ultrasound treated groups compared to the untreated groups, after 7 days. Therefore they concluded that low-intensity ultrasound directly affects osteoblasts and ossifying cartilage, with consequential more active ossification. Cyclooxygenase-2 regulates the production of Prostaglandin E2 by osteoblasts, both of which are thought to be an essential part of fracture healing (Zhang et al., 2002). Ultrasound stimulation has been found to increase cyclooxygenase-2 expression and to promote bone formation in osteoblast via various signalling pathways (Tang et al., 2006). Together with prostaglandins, nitric oxide is a crucial mediator in early mechanically induced bone formation. Reher et al., (2002), investigated the effect of traditional (1MHz, pulsed 1:4) and a long-wave (45 kHz, continuous) ultrasound on nitric oxide induction and prostaglandin E2 production in vitro, on human mandibular osteoblasts. A control group was set which was treated with sham ultrasound. They found a significant increase in both induced nitrate and prostaglandin E2 production. Long wave ultrasound was found to be more effective than the traditional ultrasound. Other studies suggest that ultrasound may have an effect on the regulation of genes necessary for osteogenesis. Suzuki and his colleagues (2009) studied the typical osteoblastic cell line in the presence or absence of daily low intensity pulsed ultrasound stimulation at 1.5 MHz frequency, and 30 mW/cm2 intensity, for 20 minutes, for 2 weeks. They concluded that stimulation with these parameters directly affected osteogenic cells, leading to mineralized nodule formation, thus low intensity pulsed ultrasound therapy is likely to have an influence on the activities of osteoblasts in alveolar bone. Clinical studies gave controversial conclusions in this area. In a review, Busse et al., (2002) concluded that evidence form randomised controlled trials suggest that low intensity pulsed ultrasound therapy may significantly reduce the time of fracture healing for non-operatively treated fractures. Five years later, Walker, Denegar, and Preische, (2007) confirmed this finding through another review. Moreover, Della Rocca (2009) reviewed studies about the effects of low-intensity pulsed ultrasound treatment in fracture healing and found a large body of animal and cellular research which shows this to be beneficial in simulating faster normal fracture healing. However, from a review to of randomised controlled trials to determine the effectiveness of low intensity pulsed ultrasound in fracture healing, Busse et al., (2009), concluded that the evidence available has a moderate to very low quality and provides conflicting results. Pain relief There are a very small number of studies which investigate the effectiveness of ultrasound in pain relief. Nevertheless, assuming that ultrasound promotes healing and resolves inflammation, pain should consequently decrease. Levent, Ebru, and Gulis (2009), used a randomised controlled trial to study the effect of ultrasound therapy in knee osteoarthritis. They applied ten sessions of five minutes of continuous ultrasound at 1 MHz to the experimental group and sham ultrasound to the control group to act as a placebo. They assessed pain by a visual analogue scale (VAS) and found that the decrease in pain in the experimental group is statistically significantly more than the control group. Thus they concluded that therapeutic ultrasound can be used effectively as a pain relief modality in patient suffering from knee osteoarthritis. An earlier review by Brosseau et al., (2001), did not show ultrasound as clinically important for pain relief in people with patellofemoral pain syndrome. However, they were unable to draw a conclusion regarding its use due to methodological flaws and limitations in the studies included in this review. Soft tissue injuries Wilkin, Merrick, Kirby and Devor (2004) studied the effect of pulsed ultrasound applied once daily for a week, on the healing of skeletal muscle in eighty rats. The results suggest that pulsed ultrasound as administered did not accelerate or improve regeneration of skeletal muscle tissue after contusion. Similarly, Markert, Merrick, Kirby and Devor (2005), using a randomized controlled trial with rats, found no evidence that specific continuous ultrasound and exercises protocols enhance skeletal muscle tissue regeneration following contusion injury. Takakura et al. (2002) investigated the effect of low-intensity pulsed ultrasound on the rate of healing of injured medial collateral ligaments of rat knees and found a significant improvement in the mechanical properties on the twelfth day, which however was lost by the twenty-first day. Nevertheless they also observed a larger mean fibril diameter in the ligaments treated with ultrasound, concluding that low intensity pulsed ultrasound enhances the early healing of medial collateral ligament injuries. Ebenbichler et al., (1999) investigated the effect of ultrasound in the treatment of calcific tendinitis. This study suggests better outcomes with ultrasound treatment. Since only patients with calcific tendinitis diagnosed by diagnostic imaging were included in the study, results are more valid than if numerous shoulder pathologies with different cellular process were included. This study was included in the review by Alexander et al., (2010). The latter carried out a review from various electronic databases and identified eight randomised controlled trials out of a total of seven hundred and twenty seven, which met their inclusion criteria. All the studies reviewed focused on shoulder musculoskeletal disorders. They concluded that statistically significant improvements were observed generally in studies which used higher levels of total energy and those who used longer exposure times. They noted favourable outcomes when at least 2,250J per treatment session was applied. This is fur ther suggested by the frequency resonance hypothesis, which suggests that the mechanical energy produced by the ultrasound wave may be absorbed by proteins, altering the structure of individual proteins or changing the function of a multi-molecular complex. Thus it may affect enzymatic proteins, inducing temporary conformational shifts, and thus alter the enzyme activity and cell function. This hypothesis implies that different frequencies will cause unique resonant or shearing forces which will therefore have specific effects at cellular and molecular levels (Johns, 2002). Thus further reviews should address different parameters used in different studies, in attempt to establish effective doses. Blood flow Noble, Lee, and Griffith-Noble (2007) applied ultrasound at 3 MHz frequency and 1 Wcm-2 for 6 minutes to assess its effect upon cutaneous blood flow by laser Doppler flowmetry. They also measured skin temperature. They concluded that cutaneous blood flow increased significantly with ultrasound even though no significant changes in temperature had occurred. Nevertheless, blood flow changes in skeletal muscles have not yet been established. Robinson and Buono (1995), investigated the effect of continuous ultrasound on blood flow using 1.5 Wcm2 intensity for 5 minutes and found no significant change in skeletal muscle blood flow. Wound healing Other authors have studied the healing rates varicose ulcers by ultrasound and found more marked healing of insonated ulcers (Dyson, Franks, Suckling, 1976). However more recent studies suggest that ultrasound does not have an influence on the acceleration of healing or final stage of the wound healing (Dolibog, Franeki, Taradai, Blaszczak, Cierpka, 2008). Different findings may be attributed to the different nature of the injuries studied and the different way by which the effectiveness of ultrasound is assessed. Diagnosis of stress fractures Romani and his colleagues (2001), were some of the few people who investigated the effectiveness of ultrasound therapy in the diagnosis of stress fractures. They used 1 MHz of continuous ultrasound therapy in twenty-six subjects with pain in the tibia since less than 2 weeks. Each subject completes a visual analogue scale after each different intensity was applies to assess the pain response to ultrasound. An MRI was taken to ascertain the diagnosis. However none of those who were found to have a stress fracture by MRI were correctly diagnosed by ultrasound. Following this review of literature, it is suggested that there may be a specific therapeutic window for ultrasound therapy. Conflicting results were obtained, possibly due to the different doses and frequencies used in various studies, indicating the need for further future research to identify the most effective parameters. Fortunately, none of the studies reviewed mentioned any negative effects on patients, making ultrasound a relatively safe modality when precautions are taken, and thus would make an important physiotherapy modality if its use is justified.