Psychology Paper free essay sample

In this paper I am going to be talking about the philosophy of psychology in the 19th century. I am going to be discussing the roots in early philosophy leading into the 19th century that influenced the development of modern psychology, identify philosophers that historically relate to the beginnings of psychology as a formal discipline, identify major philosophers in the western tradition that were primary contributors to the formation of psychology as a discipline and explore the development of the science of psychology during the 19th century. There were several philosophers that historically relate to the beginnings psychology as a formal discipline. John Locke, George Berkeley, David Hume and John Stuart Mill are just a few to mention. John Locke made a distinction between simple and complex. â€Å"Simple ideas resulted from experiencing basic sensory qualities such as yellow, white, heat and so on, and from making simple reflections such as â€Å"pleasant. We will write a custom essay sample on Psychology Paper or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page † A complex idea includes sever ideas, which can be a combination of simple and other complex ideas. Complex ideas are compounds and can be ultimately reduced to simple ones, much as chemical compounds are composed of simple elements. (Goodwin, 2008). David Hartley, another dualist, believed that although the mind and body operated separately but also parallel to each other. He used association in his theory of memories. He believed the â€Å"strength of association relies on repetition† (Goodwin, 2008). John Stuart Mill, known as the â€Å"key transition figure in the shift from the philosophy of the mind to the science of the mind† (Goodwin, 2008), used a chemical rather than mechanical description in our complex ideas are made from simple ones. He believed that the mind was much more active than passive. Mill’s logic consists of the Method of Agreement, Method of Difference, and Joint Method.

buy custom Entrepreneurial Finance essay

buy custom Entrepreneurial Finance essay Venture Capitalists Venture capital is a fund or a capital pool that is established to make early to late stage types of investments in private equities. Venture capitalists in most circumstances invest in small private entrepreneurships with the hope of capital gains after such activities as Initial Public Offerings (Metrick Yasuda 2007, p. 430). Such exit outcomes or acquisitions in most instances happen within three to five years after the investors initial investment. In such situations, the venture capitalists pay comes from the initial investments as well as any profits that the company makes. The profits are therefore split between the given company and the investor. A business venture is a high-risk investment since it happens at an early stage of a business. Venture capital management is carried out by companies with great expertise in the given sector. Venture capitalists act as a great source of funding. In addition, they help manage and develop small companies (ed. Landstrom 2007, p. 70). However, there exists a great deal of risks associated with these types of ventures. Therefore, it is crucial that the venture capitalist adopts mechanisms that can mitigate the expected risks. Mitigation of such risks increases the chances of greater capital returns from the business. This paper intends to explore the risks and possible mechanisms available to venture capitalists for eliminating the risks. Risk and Risk Mitigation Mechanisms used by the Venture Capitalists A person who decides to make an investments in the venture capital often faces several risks. However, it is important that the lender understands possible risks and analyses the available risk mitigation mechanisms. The probable risks form the following list. Risks of the Unknown When choosing a business to invest in, both hi-tech and low-tech options are considered. However, most argue that for the former, understanding of the given product or service qualifies is requied for one to make an investment in such a business. However, ed. Cumming (2010, p. 110) posits that most ventures take a lot of time to become successful and great ideas. The biggest challenge of a venture implementation is in the details as well as execution. For example, an individual with an e-commerce background may find it difficult to make an investment in a devices used for orthopaedics. Such decision may require the e-commerce investor to spend much time in trying to find out the right amount of field trials needed before pitching the venture to the right acquirer. For example, a firms such as Andreessen Horowitz dealing with the line of consumer products as well as services in the United States is a good example of a successful venture in 2014. To achieve such success, the organisati on had to mitigate several risks such as the fear of the unknown. To mitigate such risk, the venture capitalist may only invest in the areas where the venture managers, as well as the fund managers, have reasonable knowledge. In such cases, if the investor has interest in funding and supporting an idea where the funding management has little or no expertise, the fund management team should consider appointing an advisor (Malerba et al. 2015, p. 140). It should be an individual who is equipped with the needed skills and willing to work closely with the investment team. Risk of Running Out of Cash Before getting the right funding, most ventures are in a bootstrapping mode. The spending in such ventures is conservative, and the prediction of expected revenue is optimistic. If an idea of such a business spreads virally, it works. To mitigate a risk of the lack of cash, the venture capitalist should assess how much money is needed according to the most rational forecast. According to Tobin Parker (2009, p. 130), to achieve this aim, the outflow is multiplied by 1.5 and the cash inflows - by 0.5. The company that is suitable for funding is the one with at least a 20% more than the number one arrives at. Essentially, a start-up organisation requires at least 18 months runway. In addition, the venture capitalist can make a syndicate with an individual who can oversee the follow-up of the investment. The Risk of Competition Any venture entering the market has to guarantee profits for its investors and thus outdo the competitors successfully. There are not many fields with barriers to entry, but an example of such sphere may be technology. As such, such kinds of markets and ventures become more attractive for investors as compared to obvious and average products. The technological development in a successful organisation may act as the tool for increasing its competitiveness (eds Lee, Lee Lee 2010, p.767). An example of a successful venture capitalist is Steve Anderson, who decided to invest in Instagram before other bigger venture capitalists, and the decision paid off well with Facebook bought the company. Such an investor had made an assessment of the risk of competition and by investing had mitigated the risk. To mitigate this risk, venture capitalists have a duty of identifying such ventures. In addition, investors can promote and fund technological developments of such businesses. Through applying such mechanisms and increasing competitive edge, the organisation becomes protected from competition. Moreover, most venture capitalists prefer to fund organisations with better quality of science. Due to the risks associated with the competition, venture capitalists at times decide to fund the venture in stages. More investment depends on passing a given milestone (Metrick Yasuda 2007, p. 430). Entrepreneurial Environment and Implementation Risk Venture capitalists have greater interest in companies situated in a favourable entrepreneurial environment. Favourable entrepreneurial environment has a sufficient number of companies with similar products, hence there is a large pool of talent. When there are several small similar companies in the same area, the CEOs can have sessions for sharing ideas and developing given solutions. Such environment also may support a large number of attorneys as well as accountants who are familiar with the venture. Buy custom Entrepreneurial Finance essay

The 1992 European Exchange Rate Mechanism Crisis Case Study

The 1992 European Exchange Rate Mechanism Crisis - Case Study Example had exited the European exchange rate mechanism and that interest rates would remain unchanged at 12%, Italy was also affected by the crises on that same day and exited from the European exchange rate mechanism although it rejoined the union some years later.3 The UK crises can be linked to the failure of the regime to establish a crisis prevention and management mechanism within the union, if there existed a crisis management mechanism within the union it would have prevented the occurrence of the financial loss by the UK. In the ERM the currencies were floated and the exchange rate was determined by the market, the market forces dictate that if a currency is highly demanded then the currency will revalue and on the other hand if a currency is less demanded the currency will devalue. The crises in the UK can be linked to this market forces that determine the exchange rate of a currency, the government strategy at the time was to create demand for the pound by raising interest rates but this turned fruitless because speculators and investment banks were already aware of the strategy behind such a decision, speculators and investment banks therefore sold the pound to hold other currencies and this led to crisis in the UK which saw the devaluation of the pound. An expansionary monetary policy by a member of the European exchange rate would result into low interest rates among the other member countries, this would lead to the appreciation of all the other currencies, therefore there was a need to coordinate the policies among the member countries of the European exchange rate mechanism, the optimal coordination response to an aggregate demand shock by a member country was a set of small devaluations by the other countries, however this was not the case in this regime... The researcher of this case study concludes that the 1992 crises in the UK was as result of increased conflicts and lack of commitment among members of the European exchange rate mechanism. This led to frequent speculative attacks where the speculators and investment banks were aware of the strategies of individual central banks that led to great financial losses. The European exchange rate mechanism was initially formed to stimulate trade and investment among member countries of the union; it was also to be used as a tool that would help maintain a stable exchange rate among the currencies of member countries where countries were allowed a 2.25% fluctuation margin. However, interest rates and government policies were determined through market forces and were no longer influenced by external forces, this has led to a stable economy in the UK. In 1999 the European exchange rate mechanism was replaced by European exchange rate mechanism 2, the new mechanism seem to be better than the o riginal mechanism in that in this system currencies were allowed to float under a margin of 15% against the euro, this system is also better than the original because in that it uses the euro as the central unit of determining exchange rates. The European exchange regime would have been beneficial to member countries only that there was an increase in the level of conflict and decrease in coordination of policies, the regime led to great losses but was also beneficial in that it stimulated trade and investment among the member countries.

Final Exam Paper Essay Example | Topics and Well Written Essays - 750 words

Final Exam Paper - Essay Example It also gives the impression of a performance within a performance, as he moves from frame to frame. The relationship between Alfredo and the boy Toto is the central theme of the film. The two actors act and react with each other, and the boy provokes the old man in various ways, so that he becomes cross at first, and impatient. Over time he mellows, however, and there are many camera shots of the two of them together, the boy in Alfredo’s lap, or on the handlebars of his bicycle, as if the little boy is in the shadow of his protective grandfather figure. At the time when Toto grows up and leaves his mentor, the old man has become weak, and the young man has become strong, reversing the relationship in a poignant way. Salvatore is first seen in the city behind the windscreen of his car, which puts his face in a wide angle frame. After that he goes to his bedroom and looks out through a window, which makes the frame tall and narrow. When the flashback to his village begins, it shows the dusty scene through the square opening of the bell tower, as if the eye of memory looks out from a small space into the wider world. The child Toto is shown clutching scraps of film in his hands through the frame of an internal window. The adolescent Salvatore looks up at Elena’s window with longing, and his first kiss takes place in the same small projection box in which he learned about love. The message here is that life comes through the window of the cinema screen, and this is made most clearly of all in the long scene where Salvatore watches the collage of screen kisses that Alfredo has left to him. This arouses Salvatore’s affective memory, reminding him of the impoverished childhood that he had, and the longing to grow up and escape from the constraints of his village to experience love and real life in the world beyond. Part Two The character of Rick in Casablanca is quite similar to the character of Alfredo, in some ways. He is portrayed as a somewh at distant and unfeeling person, hiding under his hat and smoking quietly so that no-one can guess what he is thinking. He is at home in the dark night club scenes, with shady characters and this is conveyed by the dim lighting of Rick’s cafe. The skill of the director is evident in the way that the audience is at first led to believe he is a bad character, always in the shadows but in the end the farewell scene shows that his gloom is because of sadness at the loss of his love, and he really is a noble character. Like Alfredo, Rick needs the presence of a completely different person to bring out his true nature. The female lead character is often shown in close-up and her acting is expressive. She reacts to Rick’s enigmatic silences with passionate looks, and provides the other side of the story that Rick is not telling anybody. There is a whole back story that only gradually is revealed. Ingrid Bergman has is open and sympathetic, where Humphrey Bogart is cynical and deceptive. Both films show how opposites attract, and enhance each other, but there is an element of nostalgia about them, since separation is the only way that they can live their lives. In both films kisses are the force that heals their pain. In Casablanca Rick and Ilsa’s bittersweet kiss is not a standard happy ending, because there are too many obstacles in the way for them to be together, especially Ilsa’s husband. In Cinema Paradiso the collage of kisses are like an intense reminder of all that is most

Demand and Stores Coursework Example | Topics and Well Written Essays - 750 words

Demand and Stores - Coursework Example Therefore, the average daily demand during lead time is equal to L ? AVG. The safety stock is determined scientifically and is applied with the average daily demand during lead time to ensure that there is an adequate supply of inventory is in stores to prevent a loss of sale due to stock-out. The safety stock, which is the minimum level to which stock is expected to fall, is represented by the formula: z ? STD ? vL It is expected that inventory will fall to this minimum level just before the order for Q is received. Immediately after the order for Q units is received the inventory will return to its maximum level but will be depleted over time based on the average daily demand (AVG). The reorder level depends on AVG which is reviewed continuously. When Q units are added to the safety stock the maximum inventory level is achieved. This inventory is depleted over time. Therefore, it is expected that the expected level of inventory before receiving the order is: z ? STD ? vL While the expected level of inventory immediately after receiving the order is: Q + z ? STD ? vL Solution to Question 2 The periodic review inventory replenishment policy requires that inventory be reviewed periodically at regular intervals and that an appropriate quantity is ordered so as to achieve the base stock level after each review. This level of inventory should be sufficient to cover demand during the review period (r) and the lead time (L), in order to prevent stock out before the next order arrives. This implies that the base-stock level includes the average demand during the combined interval of r + L which is: (r + L) ? AVG as well as the safety stock which is calculated as: z ? STD ? v(r+ L) According to Simchi-Levi et al (2008), the maximum inventory level is reached immediately after receiving an order while the minimum level of inventory is reached just before receiving the order. It is therefore very clear that the expected level of inventory after receiving an order is equa l to: r ? AVG + z ? STD ? v(r+ L) while, the level of inventory immediately before order arrives is: z ? STD ? v(r+ L) which is the safety stock. Solution to Question 3 The target service level defines the percentage of orders received that must be filled. A good criterion that can be used is price. The five products that I sell in my department store are: shoes, clothes, appliances, furniture, and food items. In order of target service level from lowest to highest they will be listed as follows: Furniture – more expensive than all other items, profit margin is low, volume is relatively low, demand variability and lead time is high. Appliances – less expensive than furniture but tend to be more expensive than all other items, profit margin is high compared to furniture, volume medium range, while both demand variability and lead time is relatively high Foot-wear – the profit margin is high, volume relatively high, demand variability is not as low as with clothes , and lead time is not as low as with clothes Clothes – the profit margin is high, volume relatively high, demand variability is also relatively low while lead time may not be as low as with food items. Food items – they are cheaper than all other items; the profit margin tend to be low but turnover rate and volume is high, both demand variability and lead time is generally low. According to Simchi-Levi (2008) the service level is generally higher for products with high profit margin, high volume, low variability

Efficacy of Growth Factors Concentration after PRP

Efficacy of Growth Factors Concentration after PRP Efficacy of growth factors concentration (hGH, IGF-1, FGF-2, PDGF, VEGF) after autologous Platelet-rich plasma injection (PRP) on accelerating healing of proximal hamstring tear for athletes. Ahmed Gaballah 1- Department of Sports Health Sciences, Damietta University, Damietta, Egypt. 2- Kinesiology and Health Sciences Department, Utah State University, Logan, UT, USA Abstract Platelet rich plasma (PRP) become popular biologically method used to accelerate healing in sports medicine and orthopaedic surgery field. PRP is concentrate the human platelets to supra-physiologic levels. It is an autologous producing high level of the platelets concentration centrifuged from the peripheral vein. Then it re-injected under the ultrasound gaudiness during surgery or at a site of injury. METHOD: Seventeen physically active males (age 22.0 ±0.6) with acute hamstring strain injuries divided to 8 case group and 9 matched controls (age 21.6 ±2.8) were recruited as research participants. Case group participants were injected with single 3 ml of extracted PRP under ultrasound gaudiness. However, Blood samples were collected by venipuncture at standardized time points: before the injection and 24, 48, 72, and 96 hours after for case group and 4wks. and 8wks for both groups. RESULTS: there was significantly difference between the growth factors results of the case group a fter 4 weeks compared with the 8 weeks result of the control group. Additionally, the same significant results between the two groups after the 8 weeks. Nevertheless, the physical measurements related with hamstring Strain and Knee flexion range of motion between the two groups were not significant after 4 weeks or 8 weeks. CONCLUTION: a single 3-mL injection of autologous PRP combined with a rehabilitation program was effective in time return to play and reducing the severity of pain after an acute grade 2 hamstring injury. Additionally, increase in circulating concentrations of VEGF, IGF-1, PDGF and FGF-2. Key Words: Platelet rich plasma (PRP), Human Growth Factors, Hamstring Tear. 1. Introduction: Skeletal muscle injuries are up to 55% of all sports injuries and causes excessive long term pain and physical disability, Muscles strains and contusions representing more than 90% of all sports related injuries and are the most muscular injuries frequent. [1] [2]   Proximal hamstring tear injuries are common in athletes and frequently result in prolonged rehabilitation, time missed from play, and a significant risk of re-injury. Reports of acute hamstring strains without avulsion in dancers have suggested recovery times for return-to-play ranging from 30 to 76 weeks [3]. Platelet rich plasma (PRP) become popular biologically method used to accelerate healing in sports medicine and orthopaedic surgery field. PRP is concentrate the human platelets to supra-physiologic levels. It is an autologous producing high level of the platelets concentration centrifuged from the peripheral vein. Then it re-injected under the ultrasound gaudiness during surgery or at a site of injury [4] [5]. As a result of the lack side-effect and the autologous nature of PRP, it has utilized exponentially over the last few years in sports medicine and orthopaedic. Historically, since the 1950s the platelet-rich plasma (PRP) has been used to dermatological conditions and manage maxillofacial as well [6]. Furthermore, Platelet-derived preparations including PRP were first regulated by WADA under the 2010 Prohibited List because of concerns that the elevated concentrations of growth factors in PRP may confer an unfair advantage to treated athletes. However, WADA lifted the ban on PR P in 2011 in recognition of the lack of evidence to support a systemic performance-enhancing effect and to allow further research in the field [7]. Indeed, the blood contains 6% platelets, 1% white blood cells, and 93% red blood cells.   The PRP technique aims to reverse the concentration of the platelet in lieu of red cells to increase the growth factors that more useful in accelerating the healing. [8] However, Platelet rich plasma (PRP) is a centrifuged blood product that contains a supraphysiologic amount of platelets. Therefore, the preparation process to product concentrative platelet above the baseline values have started with an autologous extraction of patients` blood, then by plasmapheresis centrifuged to obtain a concentrated suspension of platelets. It then separates the solid and liquid components of the anticoagulated blood after a two-stage of centrifugation process [9]. The initial phase separates the plasma and platelets from the erythrocytes and leucocytes. The second stage concentrates the platelets further into platelet-rich and platelet-poor plasma components [10] [11]. Platelet rich plasma (PRP) contains some biologic factors which have been enhanced the proliferation and collagen secretion of tenocytes. These factors including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF2), and transforming growth factor ÃŽ ² (TGF ÃŽ ²) [12] [13]. There is an increasing the stimulus response of PDGF and TGF-ÃŽ ² in the early stages of tendon and muscles healing after PRP injection resulting in new vessel formation and collagen synthesis. [14]. In addition to decrease oxidative stress that could lead to cell apoptosis, PRP has been promoted tendon and muscles cell growth [15]. This is evidenced and reinforced by release of inflammatory meiators such as COX-1 and2, PGE-2 [16] [17]. Recently, there are various approaches reported the benefits of treating the soft tissue injuries such as muscles tears and tendinosis by injecting platelet rich plasma (PRP). Despite this popularization and increasing use in soft tissue injuries, its efficacy still not clear and remains controversial. It has been previously established that platelets provide regenerative potential by the process of chemo-taxis [18] [19] [20]. The use of PRP in order to accelerate recovery time after muscle injury has become a relatively common practice in sports medicine. Several studies represent that PRP can improve skeletal muscle healing after acute injury. In particular, local PRP which increased expression of several myogenic factors at mRNA level acting on modlating the inflammatory response and myogenesis in the early stages after acute injury [21] [22]. Rossi L, et al. reported the effects of an autologous PRP injections on time to return to play in randomized controlled study conducted on 75 patients. The study represented time to return to play for recreational and competitive athletes and recurrence rate after acute muscle injuries as well. The main result in the study that PRP injection significant reduction of re-injury rates at 2 years. Additionally, it was decreased the pain severity score and significantly decreased the time of return to sports as well [23]. One more study reported that 14 professional athletes were treated with ultrasound-guidance injections of PRP after acute muscle injuries. The athletes showed a quick return to activity and improved healing in muscle tears [8]. Similar results have represented in Sanchez et al study, which conducted on 20 athletes. These results supported the benefits of PRP and its role in muscle healing. The patients recovered in half of the expected time [24]. Figure 1. Process of platelet activation (PDGF, platelet derived growth factor). Source [25] Platelet Activity in muscles: (Figure 1,) represents the released serotonin contributes to vasoconstriction. The conversion of ATP into ADP releases the energy necessary to establish and maintain the aggregation. The release of the calcium ions inside the platelet makes the myofibril within it contract, thus allowing the aggregation and release of the content of the granules. This is serum calcium, which is necessary for the formation of the fibrin network [26]. The presence of the Ca2+ ions in the plasma makes the coagulation factors activate and group, forming the fibrin network, which is stabilized by factor XIII and transformed in a stable clot. The calcium ions also inhibit the anticoagulant activity of heparin, preserving the clot [27]. The PRP and the growth factors: The functions of these growth factors are presented in Table 1. It should be noted that the mechanism of action of platelet-rich plasma does not differ from the physiological healing process, but allows for obtaining higher concentrations of growth factors. As a result, the process of tissue regeneration is accelerated [28] [29] [30]. Platelet ÃŽ ±-granules are comprised of haemostatic factors, regulators inflammation, and wound healing. Substances stored in dense granules are thrombocyte-activating factors. Platelets also contain lysosomal granules, which secrete acid hydrolases [31] [32]. Platelet activation results in growth factor release. Platelet growth factors include platelet-derived growth factor (PDGF), transforming growth factor ÃŽ ² (TGF-ÃŽ ²), vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and insulin-like growth factor 1 (IGF-1) [33] [8]. Table 1. Growth Factors function Growth factor Abbreviation Functions Transforming growth factor TGF-ÃŽ ² A mitogen for fibroblasts, smooth muscle cells, osteoblasts Angiogenesis promotion, extracellular matrix production Platelet-derived growth factor PDGF Chemotactic effect on monocytes, neutrophils, fibroblasts, mesenchymal stem cells and osteoblasts A mitogen for fibroblasts and smooth muscle cells Angiogenesis promotion, formation of fibrous tissue, re-epithelialization Vascular endothelial growth factor VEGF Angiogenesis promotion Chronic wound healing promotion Inhibition of bone formation Epidermal growth EGF factor A mitogen for fibroblasts, endothelial cells, keratinocytes Chronic wound healing promotion Insulin-like growth factor IGF-1 Regulation of bone maintenance Modulator of cell apoptosis Stimulation of bone tissue regeneration Platet derived endothelial growth factor PDEGF Promotes wound healing by stimulating the proliferation of keratinocyes and dermal fibroblasts Endothelial Growth Factor EGF Cellular proliferation Differentiation of epithelial cells Figure 2. Platelet degranulation and action of the released cytokines in the process of formation of new bone and muscle tissue (VEGF, vascular endothelial growth factor; PDGF, platelet derived growth factor; BMP, bone morphogenetic protein; TGF-b, transforming growth factor). 2. Methods 2.1. Participants: This study was approved by Damietta University, Egypt, Alexandria University, Egypt and Utah state University, UT, USA. Twenty-three physically active males with acute grade 2 hamstring tear were voluntarily recruited for data collection (age 21.8  ± 2.64y, mass 71.52 ±2.74 Kg, height 175.4 ±2.32). All patients receiving local ultrasound-guided intratendinous PRP injection at our institution between September 2014 and December 2016 were screened for eligibility to participate in the study, and 17 patients were ultimately enrolled. Exclusion criteria included five participants with previous injury or diagnoses in hamstring. 8 physically active males (age 22.0 ±0.6) with acute hamstring strain injuries and 9 matched controls (age 21.6 ±2.8) were recruited as research participants. The case and control groups were performed rehabilitation program included aquatic exercise for 8 weeks. The history of pain data and the daily hours of using the smartphones were collected by surve y. Furthermore, the procedures were explained to the subjects and their written signatures were obtained on the informed consent. 2.2. Platelet rich plasma preparation and injection: In accordance of GPSTM III Systems instruction the blood collected for PRP was prepared by (Biomet Biologics, Inc., Warsaw, Ind) and standard 60 ml GPSTM III kit. Approximately of 7 ml of PRP was prepared in 30 minutes. Furthermore, single 3 ml of extracted PRP were injected under ultrasound gaudiness after adding 8.4% sodium bicarbonate buffered PRP for increasing the pH to normal physiological levels. The sodium was added in a ratio 0.05 ml to 1 ml of PRP. All the participants blood samples were stored in -25 ° Celsius and were analyzed to determine the concentration of the growth factors. The PRP injection of the current study were injected directly into the injured area under aseptic technique. The case group participants only received the single autologous PRP combined with the rehabilitation program. The participants were kept under observation for 96 hours and were performed the rehabilitation program after 5-7 days of PRP injection. Blood samples were collected by venipuncture at standardized time points: before (baseline) and 24, 48, 72, and 96 hours to 4wks. and 8wks. after administration of PRP. blood was drawn at precisely the same time each morning and at least 3 hours after eating and exercising per WADA standards Figure 3. PRP set up. 2.3. Growth Factor Quantification: Six growth factors and related molecules that are concentrated in PRP preparations were quantified in PRP and blood by direct immunoassay using the Quantikine enzymelinked immunosorbent assay (ELISA kit), as outlined   the Growth factors studied were: human growth hormone (hGH), insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3), basic fibro blast growth factor (bFGF or FGF-2), vascular endothelial growth factor (VEGF), and platelet-derived growth factor- BB (PDGF-BB). Because bFGF is present in the blood only at very low concentrations, a high-sensitivity ELISA kit was used to ensure accurate detection [34] [35] [5]. Figure 4. PRP injection under ultrasound guidance. 2.4. Rehabilitation program: A Physical rehabilitation program was performed for six weeks and designed for lower limb. In particular, hamstring muscles. both groups participants (8 case and 9 control) performed the exercises protocol once a day for 55 minutes for each training session and 5 times a week (275 M. / week). The exercise protocol was consisted of aquatic exercise and strength exercises and was divided to tree stages, the first stage was focused on the flexibility and isotonic strength exercise with 5 sets and 12-15 1RM intensity. While, the second stage was designed for strength exercises with 3 sets and 8-10 1RM intensity. While the third stage for endurance and exercise related of activity performance. Aquatic pool, Machine weights and The Thera-Band resistance bands exercises were used during the 6 weeks especially the colors (red, blue, black, silver). The red and blue bands were used in the first stage and the black and silver used in second stage. Furthermore, all the exercises were performed by stretching the band between 75 100 %. knowing that, the weight of stretching in Thera-Band between 75-100% is red 3.3-3.9kg, blue 5.9-7.1kg, black 8.1-9.7, and silver 11.1-13.2kg. 2.5. Statistical Analysis The paired t-test was used to compare the collected data before performing the exercise protocol (Pre-test) and those which were obtained after the 6 and 8-weeks training period (Post-test). The differences between the samples were significant at the t = 1.740 p < 0.05 level. All the analyses were performed by using SPSS 21 software for Windows 7 (SPSS Inc. Chicago, IL, USA). Additionally, all values within the text and table are observed as standard deviation and mean (mean  ± SD). 3. Results: Table 2, 3 illustrate the large variations in growth factor concentrations between participants in the two groups before and after PRP injection. Regarding growth factor (GF) trajectories for the case group participants are shown in Figure 3, and data are summarized in Table 2, the human growth hormone increased dramatically within the first 24 hours after PRP injection while these results were not significant after the 4 weeks and 8 weeks.   Moreover, IGF-1 increased relative to baseline within 24 hours after PRP and remained elevated at all-time points thereafter, and the change was statistically at 24 until 96 hours as well after 4 weeks and 8 weeks. Likewise, VEGF and PDGF were significantly elevated at 24 hours and at all-time points thereafter and were significant after 4 and 8 weeks.   Furthermore, FGF-2 rose at the point between 24 to 96 hours after PRP injection but not significantly, while it was elevated significantly after 4 week and 8 weeks. It obviously represented in table 3, the spectacular significantly difference between the growth factors results of the case group after 4 weeks compared with the 8 weeks result of the control group. Additionally, Figure 6, reveals the same significant results between the two groups after the 8 weeks. Nevertheless, the physical measurements related with hamstring Strain and Knee flexion range of motion between the two groups were not significant after 4 weeks or 8 weeks. Table 1. Data Summary for the Growth Factors after PRP Injectiona unit   Ã‚  Ã‚   Pre-test 24 h 48 h 72 h 96 h 4 weeks 8 weeks hGH   pg/mLpg/mL pg/mL 1.927  ± 0.67 8.117  ± 2.414 2.276  ± 0.030 2.776  ± 0.180 5.597  ± 1.910 2.321  ± 0.554 2.175  ± 0.651 IGF-1 pg/mL 0.577 ±0.283 1.078  ± 0.914 1.101 ±0.341 1.122  ± 0.239 1.133  ± 0.165 0.817  ± 0.844 0.793  ± 0.141 FGF-2 pg/mL 2.233  ± 1.22 2.105  ± 0.772 2.292  ± 0.736 1.911  ± 0.201 2.314  ± 0.877 3.652  ± 0.567 3.921  ± 0.822 VEGF pg/mL 0.346  ± 0.18 1.313  ± 0.42 1.544  ± 0.463 1.836  ± 0.463 1.554  ± 0.419 0.784  ± 0.098 0.749  ± 0.077 PDGF pg/mL 0.352 ±0.11 0.884  ± 0.949 1.702 ±1.572 1.602  ± 2.021 1.262  ± 1.423 0.856  ± 0.108 0.807  ± 0.133 aPRP, platelet-rich plasma; hGH, human growth hormone; IGF-1, insulin-like growth factor-1; FGF-2, basic fibroblast growth factor; VEGF, vascular endothelial growth factor; PDGF, platelet-derived growth factor. Table 2. Difference of the Growth Factors concentration between the Case and Control group Case Group (N=8) Control Group (N = 9) Unit Pre-test 4 weeks 8 weeks Pre-test 4 weeks 8 weeks P ≠¤ 0.05 hGH   pg/mLpg/mL pg/mL 1.927  ± 0.67 2.321  ± 0.554 2.175  ± 0.651 1.941  ± 0.201 1.997  ± 0.088 2.063  ± 0.477 1.215 IGF-1 pg/mL 0.577 ±0.283 0.817  ± 0.844 0. 793  ± 0.141 0.582  ± 0.247 0.633  ± 0.145 0.637  ± 0.114 1.760 * FGF-2 pg/mL 2.233  ± 1.22 3.452  ± 0.567 3.921  ± 0.822 2.228  ± 0.721 2.593  ± 0.687 2.627  ± 0.514 2.046 * VEGF pg/mL 0.346  ± 0.184 0.784  ± 0.098 0.749  ± 0.077 0.341  ± 0.163 0.384  ± 0.187 0.396  ± 0.106 2.584 * PDGF pg/mL 0.352 ±0.117 0.856  ± 0.108 0.807  ± 0.133 0.358  ± 0.121 0.421  ± 0.633 0.429  ± 0.008 2.632 * PRP, platelet-rich plasma; hGH, human growth hormone; IGF-1, insulin-like growth factor-1; FGF-2, basic fibroblast growth factor; VEGF, vascular endothelial growth factor; PDGF, platelet-derived growth factor; N, Number; * Significant difference P ≠¤ 0.05, t =1.740 (N= 17). Table 3. Difference of Hamstring Force and Knee Flexion (ROM) between the Case and Control group Case Group (N=8) Control Group (N = 9) Unit Pre-test 4 weeks 8 weeks Pre-test 4 weeks 8 weeks P ≠¤ 0.05 HF N 26.62  ± 4.67 104.32  ± 5.67 107.06 ±1.64 25.31  ± 3.41 102.71  ± 4.75 105.75  ±3.18 0.743 KF(ROM) Deg. ËÅ ¡ 51.72  ± 5.17 147.92  ± 0.43 148.62  ± 0.78 52.04  ± 2.43 147.02  ± 0.14 147.36  ± 0.88 0.632 aPRP, platelet-rich plasma; HF, Hamstring Force; KF(ROM), Knee Flexion range of motion. N, Number. P ≠¤ 0.05, t =1.740 (N= 17). 4. Discussion: There is little published evidence to support whether a statistically significant increase in growth factors with performance-enhancing potential, including IGF-1, hGH VEGF, PDGF and FGF-2, necessarily leads to clinically relevant ergogenic effects. This is further complicated by evidence from some animal studies that local IGF-1 overexpression enhances local muscle mass and strength without systemic increases in IGF-1. The current study aims to determine the effect of PRP in accelerate the healing of hamstring strain. Moreover, to identify potential molecular markers that could be used to distinguish athletes who have been treated with local PRP injections from those who have not. Figure 5, The concentration of the growth factors after the PRP injection. PRP, platelet-rich plasma; hGH, human growth hormone; IGF-1, insulin-like growth factor-1; FGF-2, basic fibroblast growth factor; VEGF, vascular endothelial growth factor; PDGF, platelet-derived growth factor. The performance of the growth factors after a single PRP injection was enhanced and increased significantly from 24 until 96 hours.   Indeed, hGH was peaked within the 24-hour window, although the results were not significant after 4 weeks or 8 weeks. Similarly, IGF-1 is significantly increased by 24 until 96 hours after PRP, while its activation was decreased after 4 weeks and 8 weeks but with significantly difference compared with the pretest and the control group 8 weeks test. Furthermore, IGF-1 is generated in the liver in response to hGH, is the primary downstream mediator of hGH, and is the most specific marker of supraphysiological hGH exposure [36] [37]. Figure 6. Difference between the case and control group in the concentration of the Growth Factors after 8 weeks. hGH, human growth hormone; IGF-1, insulin-like growth factor-1; FGF-2, basic fibroblast growth factor; VEGF, vascular endothelial growth factor; PDGF, platelet-derived growth factor. Despite that both groups performed the same rehabilitation program, our study reported a significant increase in the growth factors for the control group after 4 and 8 weeks (Table 3, figure 6). However, the values of the case group after 4 weeks for the case group were more advanced than the 8 weeks values of the controlled (Figure 7,8). Therefore, the PRP injection enhanced the concentration of the growth. It is notably that the physical measurements of hamstring force and knee flexion range of motion were not significant at either 4 or 8 weeks. Wallace et al demonstrated that an acute bout of exercise increases total circulating IGF-1 by only about 20% [38] [9]. Figure 7, Difference between the case and control group in (NFROM) Knee flexion range of motion after 8 weeks. Figure 8, Difference between the case and control group in (HF) Hamstring Force after 8 weeks.          By comparison, participants in case group who treated with PRP and exercise program. Our study demonstrated a 38% increase in IGF-1 in case group and 9.5% in control group. Relative to baseline, suggesting that PRP treatment activates the hGH-IGF-1 pathway but that a single PRP injection is important to combined with the exercise to maximally stimulate. [39] [9] (Table 3) (Figure 6). We also observed FGF-2 and VEGF also peaked after treatment with PRP.   Fibroblast growth factor contributes to angiogenesis by stimulating the proliferation of endothelial cells to enhance the proliferation of satellite cells, which are the stem cells of mature muscle [40]. Basic fibroblast growth factor may enhance athletic performance by inducing muscle hyper- trophy and increasing oxygen transport. Vascular endothelial growth factor is a powerful stimulator of angiogenesis and could have noteworthy performance-enhancing effects if it entered systemic circulation and exerted its effects in tissues o ther than the site of injury [41]. The potential effects of autologous biological substances to hasten muscle healing were reported in several case reports [34] [42] [43]. Borrione et al [34] noted that athletes with grade 3 muscle strains treated with PRP showed earlier functional improvement and more complete recovery than those treated nonoperatively. Hamid et al   [44] demonstrated that a single PRP injection was effective in accelerating recovery for grade 2. However, the PRP Group achieved full recovery significantly earlier than controls and returned to play after 27 days while control group returned after 43 days. Another approach successfully treated an athlete with a grade 2 semimembranosus muscle injury with a single 3-mL infiltration of platelet-enriched plasma under ultrasound guidance. The athlete was pain free and allowed to train at the preinjury intensity 21 days after treatment [45]. The effect of a preparation rich in growth factors (PRGF) to hasten muscle recovery was reported in a 35-year-old pr ofessional bodybuilder diagnosed with a right adductor longus rupture. The athlete successfully returned to competitive training within 1 week after the third PRGF injection [43]. The effect of PRP in accelerated and associated a hamstring injury was also observed in the current study. The PRP preparation contained a high concentration of several growth factors including TGF-b, FGF-2, and insulin-like growth factor-1, but the amount of platelets and WBCs present was not stated. Additionally, the actual effect of PRP on soft tissue healing is not fully understood,22 our findings supported the possible role of higher growth factors (concentration level) in hastening recovery as postulated by previous researchers [46] [47] [42]. Sanchez et al reported full functional recovery of hamstring and adductor muscle injuries 2 times faster in 20 professional athletes treated with a PRGF [24]. Similar designed study by Rettig et al was investigated the effects of an autologous PRP injection and was retrospective case-control study conducted to determine the effect of the PRP on return time to play after acute hamstring injuries. The study included 10 professional National Football League (NFL) players with acute hamstring injury. The participants were divided equally into PRP and Control groups. Under ultrasound guidance the PRP group patients were injected once with 6 mL of PRP. Both groups were performed the same rehabilitation program. Several differences were identified between the study by Rettig et al and the current study. For instance, the

Neural Networks in Investments Essay -- Computers Technology Investing

Neural Networks in Investments I. ABSTRACT Investment managers often find themselves overwhelmed with the large amount of data obtained from the financial markets. Most of the data available is numeric and noisy in nature, making the decision-making process harder. These decisions usually rely on the integration of statistical measures that attempt to compress much of the data and qualitative depictions such as graphs and bar charts with news events and other pertinent information. Investment decisions usually involve non-linear relationships among the various components of the data. Computers in general, are very adept at dealing with large amounts of numeric information. However, some algorithms are crucial in analyzing and combining disparate information that can impact security prices. Artificial Intelligence based methods uses clever algorithms and rules of thumb (heuristics) in the decision-making process. Neural Network and expert systems applications have been successfully deployed in the domain of Finance, and in the area of investment management. This paper discusses the basics and the theory behind neural networks and provides an introduction to an application area of neural networks in the domain of Finance. The application areas of Neural Networks discussed in the paper are corporate finance, financial institutions, and the professional investor. The purpose of the second paper will be to discuss the specifics of each of these applications. II. INTRODUCTION Neural network computing is an information processing method that was developed from research to make computers that could imitate the way people learned. The field initially grew from 1930s ideas about how biological systems like the human brain works... ...in of finance is essential for further development. V. REFERENCES 1. Deboeck Guido J., Trading on the Edge: Neural, Genetic, and Fuzzy Systems for Chaotic Financial Markets, John Wiley & Sons Inc., 1994. 2. Trippi Robert R., Lee Jae K., State-of-the-Art Portfolio Selection Using Knowledge Based Systems to Enhance Investment Performance, Probus Publishing Company, 1992. 3. Refenes Paul, Neural Networks in the Capital Markets, John Wiley & Sons Inc., 1995. 4. Proceedings of the Second International Conference on Artificial Intelligence Applications on Wall Street, April 19-22 1993, New York City. 5. Neural Network Resources on the World Wide Web, http://www.med-web.com/nnres/ 6. Neural Network Toolbox, http://www.mathworks.com/products/neuralnet/ 7. Neural Network WWW References, http://ftp.funet.fi/pub/sci/neural/www/www-catalogue.html