The Urbanization of The Internet Essay Example | Topics and Well Written Essays - 500 words

The Urbanization of The Internet - Essay Example By looking at Myspace and Facebook we can see the same fear, flight, and the slow reintegration that that is characteristic of American cultural attitudes. Myspace, one of the original social networks, was created to be open to everyone, while Facebook was exclusive. Loose security at Myspace made the site a haven for predators, danger, and disreputable behavior. Facebook was established to eliminate the perils that were inherent on Myspace. It was created as a college only site, which had the socio-economic implication that the poor and uneducated need not apply. This is similar to the racial fear of the previous half-century that saw the white population fleeing the decaying inner cities for the exclusivity of suburbia. This same phenomenon was echoed in the creation of Facebook. Myspace continued to be a haven for deviance and what Danah Boyd calls the "subaltern teens", while Facebook had attracted a more urbanite client base with an 'invitation only' strategy. Social networking requires that friends exist on the same system. This is consistent with the changing landscape of America's socio-economic division.

Portfolio Trading Strategies Essay Example for Free

Portfolio Trading Strategies Essay Profits in equity are a function of timing and costs. Trading strategies are essentially focused on maximizing profits through cost maximization which in turn is linked with transaction costs. Thus cost of trading in also a consideration for determining trading strategy. Transaction costs are said to include commissions, execution and opportunity costs. (Collins. Fabozzi : 1991). Commissions are most easy to define as these are fixed and relate to the fees paid for trading. However there is a problem of measuring execution and opportunity costs as these are neither fixed nor can be easily measured. While a number of approaches have been developed for measuring opportunity and trading costs, a method to suit all circumstances has not been evolved thus far. The complexities involved and since minor differentials make major variation in profits an effective strategy to constantly provide yield is difficult. Investment strategies thus attempt to rationalize trading to provide benefits from execution as well as opportunity costs. Since there is no uniform strategy that can assure trading profits it is very difficult to balance the large number of factors which affect trades. Timing in fact is a constant which affects both opportunity and execution costs. Opportunity Costs and execution costs are both a variable component of transaction costs. Thus profits in transaction are determined by opportunity and execution costs and the balance that will be maintained between these. Opportunity costs are the performance shortfall that arises from a failure to execute the desired trade at the desired time. These indicate the difference between actual investment and the performance of a desired investment. This is adjusted for fixed and execution costs. Thus opportunity cost is incurred for not being able to implement the desired trade. Since opportunity costs are missed investment opportunities, these could in some respects be called hypothetical costs and thus are difficult to calculate. (Collins. Fabozzi : 1991) Execution costs arise out of the demand for immediate execution and are said to reflect the demand for liquidity and the trading activity at the time and date of conducting trade. (Collins. Fabozzi: 1991). These vary with the investment style and trading demands of the investor. Both information motivated traders and information less traders could use strategies to benefit from execution costs. The information motivated trader acts in the belief that he has superior information to that available to the average dealer. Thus he executes the trade using this information for making profits. This style of trading has a large price impact. On the other hand the information less trader allocates wealth based on a price which has been factored in the trade. These have a lesser impact than information motivated traders. The problem measuring execution costs occurs as the difference in the price of the costs in absence of a trade is not observable. (Collins. Fabozzi: 1991) Execution costs are determined by market impact and market timing costs. Market impact costs are the bid/ask spread and a price concession that compensates the buyer or seller for the risk that the investor’s transaction is information motivated.   The Market timing costs arise due to the fact that at the time of execution of the trade the asset’s price moves for reasons which are not related to the transaction.   Market impact measurement is dependent on the pre trade measures, the post trade measures and also average measures which can be undertaken throughout the day. These approaches aim to define the fair value of the trade at a particular time. It is this that determines execution costs. Market making strategy thus attempts to balance opportunity and execution costs. Patient trading strategies may result in high execution costs while aggressive trading strategies could impact the other way. (Collins. Fabozzi: 1991). On the other hand the cost management methodology is designed to capture maximum elements of the transaction process. (Collins. Fabozzi: 1991). Execution costs are also shown to be higher in an automated trading process in Paris relative to the New York Stock Exchange with floor based trading with human intervention. The lower execution in floor based system suggests that there is benefit in human intervention in the trading process. This is possible as the NYSE specialist is able to maintain narrow spreads, can anticipate future order imbalances and also helps reduce the volatility of transitory movements in share prices. Thus as specialist and floor traders use the human intellect to make time preferred trades, execution costs in manual trading are considerably lower than those in automated trading. This is also supported by the role played by market makers in forming prices and providing liquidity in the securities market as per example gleaned from the trading behavior of market makers on the New York Stock Exchange. (Madhavan. Smidt: 1993).       Reference Madhavan, Ananth. Smidt, Seymour. (1993). `An Analysis of Changes in Specialist Inventories and Quotations`, Journal of Finance, Vol 48, 1993 2. Venkataraman, Kumar. `Automated Versus Floor Trading: An Analysis of Execution Costs on the Paris and New York Exchanges, Journal of Finance, Vol 56, No. 4 3.  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Collins, Bruce M. Fabozzi, Frank. (1991).   `A Methodology for Measuring Transaction Costs`, Financial Analysts Journal, March/April 1991. Preferred language style: English(U.K.)

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.

I Am Committed to Becoming a Historian :: Statement Purpose College Admissions

I Am Committed to Becoming a Historian As a Ph.D. student in U.S. history, I would like to continue to explore the intersections of culture and economics in U.S. history, especially as they relate to working-class life and consumption. Although I am now committed to becoming a historian, my academic background has been quite varied. Disillusioned with the often reductionist truths of physical science, I transferred from the School of Engineering to State College after my first year. As an undergraduate, I not only majored in history, but also concentrated in mathematics, especially as it related to economics. For a year, I acted as an economic research assistant, and, following that, I worked on a joint project with the Federal Reserve Bank and the National Bureau of Economic Research (NBER) doing empirical research in labor economics. During the summer after my junior year, I received a research grant from Columbia, the Edwin Robbins Prize, for my senior thesis: "New York Organized Labor and Prohibition Resistance: The 'No Beer, No Work' Movement of 1919." A forgotten moment in labor history, it was a fascinating intersection of culture, gender, and class, examining the untidy boundary between "economic" and "social" life. Some local trade-unionists co-opted a catchy slogan, "No Beer, No Work," with the intent of fomenting a national general strike, attempting to save the saloon, galvanize class consciousness, and lead workers into a labor party. The strike more than failed; it never occurred. However, teasing out the relationships between the primary documents excited me like nothing I had ever done before. Though I continued to work at the Federal Reserve the following year, I knew the historian's methods, and not the economist's, were what I wanted to pursue in my graduate work. This year I received a Fulbright Scholarship to research working-class history at the University of Toronto. Presently, my research centers on the rise of Canadian nationalism in Toronto within U.S.-dominated unions after WWII. I examine how anti-Communist discourses restricted and/or enabled nationalist movements within the union hierarchy, and how that affected transnational power relations and local economic/political action. My abstract is under consideration for a conference on transnationalism, Crossing Borders, to take place in February at the University of Toronto. I also plan to present a paper, based on my senior thesis, on working-class resistance to Prohibition at the "New Frontiers in Graduate History" conference at York University in March.

Neonatal Medicine: CPAP and Ventilation in Neonatal Respiratory Distress

You are reviewing Nathan, a 12 hour old neonate with respiratory distress. He is 37 weeks gestation and was born by caesarean section following failure to progress. The oxygen saturation is 94% in 50% FiO2, the respiratory rate is 80. There is moderate intercostal recession and an occasional grunt. Your hospital participated in the â€Å"bubbles for babies† trial and you have just started to use CPAP in your unit now the trial is finished. Your registrar suggests using CPAP on this neonate, but the nursing staff have called you to arrange transfer. Questions: Would you use CPAP or ventilate and transfer this neonate? Please give reasons for your choice with reference to the current literature. In your answer you should also consider the following main points: †¢ the benefits of CPAP over ventilation, particularly with reference to your current practice environment †¢ the potential complications of CPAP †¢ reasons why ventilation may be required even though CPAP is in situ. The baby Nathan is suffering from Neonatal respiratory distress syndrome, which is a condition most often seen in newborn babies and is characterized by a difficulty in breathing.   The condition more frequently develops in prematurely born babies as their lungs are not fully developed.   The lubricant that lines the inner membranes of the lungs (known as ‘surfactant’) is deficient, thus causing difficulty in inflating the lungs and resulting in the air sacs collapsing. Surfactant helps to lower the surface tension of water that is present on the alveoli, thus helping to prevent the lung sacs from collapsing.   Usually, the condition develops in infants born before the 38 week.   The baby is cyanosed and has difficulty in breathing.   The accessory muscles of respiration are active and a frequent grunting sound is heard.   The other symptoms that may be observed include nasal flaring, shallow breathing, swollen legs, unusual movement of the chest wall, etc. The infant may be hypoxic and the CO2 levels in the blood rise.   The symptoms usually develop at birth, or a little while after birth.   The symptoms tend to worsen and may progress to respiratory failure and death.   As the prematurity increases, so does the chance of developing this condition.   This is because surfactant is produced only during the later stages of gestation in the infant.   The diagnosis of RDS in babies is made based on the history, presence of certain risk factors, Chest X-ray, Blood tests, CSF studies, lung tests, blood gas analysis, etc (Greene, 2007 & Merck, 2005). When a neonatal is born, certain signs are observed which include:- a heart rate between 110 to 150 beats per minute a respiratory rate between 40 to 70 breathes per minute absence of cyanosis, nasal flaring, grunting sounds, forceful use of accessory muscles during respiration, etc Oxygen saturation which is about 95 % the P ao2 is higher than 50 % the FiO2 is about 40 to 50 % (CCM, 2007, NGC, 2008, & Millar et al, 2004) Previously, for the treatment of RDS, ventilatory support was utilized.   This may be utilized if the blood carbon dioxide levels are high, the blood oxygen levels are low, and if acidosis sets in.   To some extent ventilation helps to reduce the infant mortality rate arising from RDS, but the morbidity to develop Bronchopulmonary dysplasia (a condition characterized by oedema of the air sacs and of the connective tissues due to persistent inflammation) is high as the young neonatal lungs are damaged from ventilation. One of the treatments that have been developed in order to overcome the limitations of ventilation is Continuous Positive Airway Pressure (CPAP).   This is an advanced form of therapy in which the upper and the lower airways receive a continuous distending pressure through the infant’s pharynx and/or nose throughout the respiratory cycle.   An endotracheal tube can also be utilized.   The device is connected to a gas source that provides humidified warm air continuously (NGC, 2008, Millar et al, 2004, Tidy, 2007). CPAP has several benefits including:- helps to maintain a normal breathing pattern helps to arrive at normal functional residual capacity helps to lower any airway resistance in the upper respiratory tract helps to prevent development of apnea prevents the airways and the air sacs from collapsing helps stimulate release of surfactant helps to increase the lung volume and lung function After expiration, CPAP helps to keep the air sacs open The chances of developing lung trauma such as barotrauma and atelectotrauma are lesser (CCM, 2007, Sehgal, 2003, NGC, 2008, Millar et al, 2004). CPAP is required in several situations that arise from RDS including:- When it is difficult to maintain the Pa02 above 50 %. When the respiratory rate is above 70 breathes per minute Excessive use of the accessory muscles of respiration The oxygen saturation falls to between 90 to 95 % The presence of apnea It can be utilized along with administration of surfactant that develops out of the   Ã‚  need to treat RDS (CCM, 2007, Sehgal, 2003, NGC, 2008, Millar et al, 2004). As the patient is not suffering from a severe form of RDS and the oxygen saturation levels have not dropped to a serious extent, ventilatory support is not required, and the patient can be treated with CPAP.   Besides, the findings do not suggest that the patient is suffering from a cardiovascular complication, an upper respiratory tract abnormality or intractable apneic episodes.   Along with CPAP, several other measures are required such as using larger nasal prongs, ensuring that the baby is in a prone position and keeping a towel below the neck.   This helps to ensure that the certain areas are aerated better (CCM, 2007, Sehgal, 2003, NGC, 2008, Millar et al, 2004). CPAP has several complications including:- mucous from the upper respiratory tract may block the nasopharyngeal tube that delivers CPAP Sometimes blockages may result in the pressure rising to higher levels in the tube If the peak pressure is very high, then gastric complications can develop The nasopharyngeal tube has to be placed in exact position.   Any deviation from the position can result in fluctuation of the air pressure The nasal devices may be swallowed or aspirated resulting in severe complications Sometimes harnesses may be utilized to place the head and the neck in position.   This may cause serious dermatological and musculoskeletal complications in the infant Air leakage problems in the lungs Abdominal distention Decrease in the cardiac output Higher working of breathing pneumothoraces and air embolism can also develop Cardiac monitoring needs to be performed more closely in the case of CPAP compared to ventilation often air leaks from the nose and the mouth it may be very difficult to control the air press ure in the lower airways If CPAP is applied to an infant with normal lungs, several problems can develop Several respiratory complications such as pneumothorax, pneumomediastinum, and pneumopericardium can develop (CCM, 2007, Sehgal, 2003, NGC, 2008, Millar et al, 2004, Halamek et al, 2006) References: California College of Midwives (20080, Guidelines for Assessing the Neonate, [Online], Available: http://www.collegeofmidwives.org/Standards_2004/Standards_MBC_SB1950/Assess_HealthyNeonate_Oct2004_OOO.htm [Retrieved on: 2008, April 2]. Greene, A. (2007), Neonatal respiratory distress syndrome, [Online], Available: http://www.nlm.nih.gov/medlineplus/ency/article/001563.htm [Retrieved on: 2008, April 2]. Halamek, L. P. Et al (2006), Continuous Positive Airway Pressure During Neonatal Resuscitation, Clin Perinatol, 33, pp. 83-98. http://www.mdconsult.com/das/article/body/91421747-3/jorg=journal&source=MI&sp=16080552&sid=690389052/N/525142/s0095510805001235.pdf?issn=0095-5108 Millar, D., & Kirpalani, H. (2004), Benefits of Non Invasive Ventilation, Indian Pediatrics, 41, pp. 1008-1017. http://www.indianpediatrics.net/oct2004/oct-1008-1017.htm NGC (2008), Complete Summary, [Online], Available: http://www.guideline.gov/summary/summary.aspx?ss=15&doc_id=6516&nbr=4085, [Retrieved on: 2008, April 2]. Sehgal A. Et al (2003), Improving Oxygenation in Preterm Neonates with Respiratory Distress, [Online], Available: http://www.indianpediatrics.net/dec2003/1210.pdf, [Retrieved on: 2008, April 2]. The Merck Manual (2005). Respiratory Distress Syndrome, [Online], Available: http://www.merck.com/mmpe/sec19/ch277/ch277h.html, [Retrieved on: 2008, April 2]. Tidy, C. (2006), Infant Respiratory Distress Syndrome (RDS), [Online], Available: http://www.patient.co.uk/showdoc/40000462/, [Retrieved on: 2008, April 2].

Filipino Politician and President Rodrigo Duterte

Filipino Politician and President Rodrigo Duterte Roderigo Roa Duterte (born March 28, 1945) is a Filipino politician, and the 16th president of the Philippines, elected by a landslide on May 9, 2016.   Fast Facts: Rodrigo Roa Duterte Also Known As: Digong, RodyBorn: March 28, 1945, Maasin, PhilippinesParents: Vicente and Soledad Rao DuterteEducation: Law degree Lyceum of the Philippines UniversityExperience: Mayor of Davao City, 1988–2016; President of the Phillippines 2016–present.Spouse: Elizabeth Zimmerman (wife, 1973–2000), Cielito Honeylet Avanceà ±a (partner, mid-1990s to present)  Children: 4Famous Quote: Forget the laws on human rights. If I make it to the presidential palace, I will do just what I did as mayor. You drug pushers, hold-up men and do-nothings, you better go out. Because Id kill you. Ill dump all of you into Manila Bay, and fatten all the fish there. Early Life Rodrigo Roa Duterte (also known as Digong and Rody) was born in the town of Maasin, in Southern Leyte, the eldest son of local politician Vicente Duterte (1911–1968), and Soledad Roa (1916–2012), a teacher and activist. He and two sisters (Jocellyn and Eleanor) and two brothers (Benjamin and Emmanuel) moved to Davao City when their father was made the governor of the now-defunct Davao province.   Education He attended high school at the Ateneo de Davao, where he has said he was a victim of sexual abuse by Rev. Mark Falvey, an American Jesuit priest who died in California in 1975- in 2007, nine of his American victims were paid $16 million by the Jesuit church for Falveys abuse. Duterte was expelled from school for retaliating against another priest by filling a squirt gun with ink and spraying the priests white cassock. He skipped classes and has told audiences that it took him seven years to finish high school.   According to his own report, Duterte and his siblings were frequently beaten by his parents. He began carrying a gun at the age of 15. Despite the hardships and chaos of his younger life, Duterte studied political science at the Lyceum of the Philippines University, obtaining a law degree in 1968.   Marriage and Family In 1973, Duterte eloped with Elizabeth Zimmerman, a former flight attendant. They have three children Paolo, Sara, and Sebastian. That marriage was annulled in 2000.   He met Cielito Honeylet Avanceà ±a in the mid-1990s, and he considers her his second wife, although they have not married. They have one daughter, Veronica. Duterte has no official first lady but said during his presidential campaign that he had two wives and two girlfriends.   Political Career After graduation, Duterte practiced law in Davao City, and eventually became a prosecutor. In the mid-1980s, his mother Soledad was a leader in the Yellow Friday Movement against the Philippine dictator Ferdinand Marcos. After Corazon Aquino became the Philippine leader, she offered Soledad the post of vice-mayor of Davao City. Soledad asked that Rodrigo be given the position instead.   In 1988, Rodrigo Duterte ran for Mayor of Davao City and won, eventually serving seven terms over 22 years. Death Squads When Duterte took over the mayorship of Davao, the city was war-torn, the result of the Philippine Revolution leading to the ouster of Marcos. Duterte established tax breaks and pro-business policies, but at the same time, he founded his first death squad in Davao City in 1988. A small group of police officers and others were selected to hunt down and kill criminals; the membership eventually grew to 500. One of the men who has admitted to being on the squad reported that there were at least 1,400 or more people killed, with their bodies dumped in the sea, the river, or a different city. The man said he received 6,000 pesos for each of the fifty people he personally killed. A second man said he received orders from Duterte to kill at least 200 people, including political rivals, one of whom was journalist and outspoken critic, Jun Pala, in 2009.   Presidential Election On May 9, 2016, Duterte won the Philippine presidential election with 39 percent of the popular vote, far outweighing the four other candidates. During his campaign, he repeatedly promised to bring the practice of extrajudicial killing of drug users and other criminals to the country as a whole, and he has fulfilled that promise.   Social workers and police round up minors at night during curfew on June 8, 2016 in Manila, Philippines. Dondi Tawatao / Getty Images According to the Philippine National Police, from the time he assumed office on June 20, 2016, to January 2017, at least 7,000 Filipinos were killed: 4,000 of them were killed by police and 3,000 by self-described vigilantes. Legacy Human rights groups such as Human Rights Watch and others such as the International Criminal Court, the former U.S. President Barack Obama, and Pope Francis have been vocal in their criticism of Dutertes death squads of suspected drug users and pushers and other criminals.   As a result, Duterte has lashed out at those critics, in what are vulgar and racist terms. However, according to a recent biography by British journalist Jonathan Miller, his supporters call him Duterte Harry (a play on the Clint Eastwood character in the Dirty Harry movies). He currently has at least the tacit support of China and Russia.   In general but not entirely, Duterte is popular in the Philippines. Political journalists and academicians such as American political scientist Alfred McCoy consider Duterte a populist strongman, who like Marcos before him offers a promise of justice and stability, and one who is clearly not subject to the West, in particular, the United States. Sources President Rodrigo Roa Duterte. Ed. Bio, Presidents. Washington DC: Embassy of the Philippines, 2018. Print.Casteix, Joelle. Philippines CA- Ex L.A. priest molested presidential candidate. SNAP Network, December 8, 2015.  Web.Lamb, Kate. Rodrigo Duterte: The President Warlord of the Philippines. The Guardian Nov. 11, 2017. Print.McCoy, Alfred W. Global Populism: A Lineage of Filipino Strongmen from Quezon to Marcos and Duterte. Kasarinlan: Philippine Journal of Third World Studies 32.1–2 (2017): 7–54. Print.McGurk, Rod. Biographer: Animosity toward Us Drives Duterte. Philadelphia Star June 2, 2018. Print.Miller, Jonathan. Rodrigo Duterte: Fire and Fury in the Philippines. London: Scribe Publications, 2018. Print.Paddock, Richard C. Becoming Duterte: The Making of a Philippine Strongman. The New York Times March 21, 2017. Print.