The Pros and Cons of Trade Deficits and Surpluses

Int. J. Med. Sci. 2009, 6 http://www.medsci.org 287IInntteerrnnaattiioonnaall JJoouurrnnaall ooff MMeeddiiccaall SScciieenncceess 2009; 6(5):287-295 © Ivyspring International Publisher. All rights reserved Review Revision of late periprosthetic infections of total hip endoprostheses: pros and cons of different concepts Bernd Fink  Department of Joint Replacement, General and Rheumatic Orthopaedics, Orthopaedic Clinic Markgröningen gGmbH, Kurt-Lindemann-Weg 10, 71706 Markgröningen, Germany  Correspondence to: Prof. Dr. med. Bernd Fink, M.D., Department of Joint Replacement, General and Rheumatic Ortho-paedics, Orthopaedic Clinic Markgröningen gGmbH, Kurt-Lindemann-Weg 10, 71706 Markgröningen gGmbH, Kurt-Lindemann-Weg 10, 71706 Markgröningen, Germany, Phone: ++49-7145-912201, Fax: ++49-7145-912922, E-mail: b.fink@okm.de Received: 2009.04.16; Accepted: 2009.09.02; Published: 2009.09.04 Abstract Many concepts have been devised for the treatment of late periprosthetic infections of total hip prostheses. A two-stage revision with a temporary antibiotic-impregnated cement spacer and a cemented prosthesis appears to be the most preferred procedure although, in recent times, there seems to be a trend towards cementless implants and a shorter period of anti-biotic treatment. Because of the differences in procedure, not only between studies but also within studies, it cannot be decided which period of parenteral antibiotic treatment and which spacer period is the most suitable. The fact that comparable rates of success can be achieved with different treatment regimens emphasises the importance of surgical removal of all foreign materials and the radical debridement of all infected and ischaemic tissues and the contribution of these crucial procedures to the successful treatment of late peripros-thetic infections. Key words: periprosthetic infections, hip endoprostheses Introduction Periprosthetic infections occur with an incidence of less than 1% of patients but nevertheless are a se-rious complication of hip arthroplasties [1,2]. When early infections occur, within 4 weeks of implantation, the implant can be left in place with a high probability of cure whereas late infections require prosthesis re-vision to eradicate the infection [3,4]. In such cases, one can differentiate between one-stage and two-stage revisions. In the former a new prosthesis is implanted immediately after the removal of all foreign material in one operation. Two-stage revision involves an ini-tial operation to remove all foreign materials and this is followed by an interim phase of 6 – 10 weeks, either left as a Girdlestone situation or with the implantation of a cement spacer. Individual aspects of both forms of revision have been treated very differently in the past so, in the following paragraphs, the different concepts are summarized and their respective ad-vantages and disadvantages discussed. One stage revision The advantage of the one-stage revision is that only one operation is required and functional prob-lems associated with a Girdlestone situation, such as leg shortening and instability, or, in the case of a ce-ment spacer, spacer fracture, abraded particles from the spacer or bone resorption, can be avoided. Most surgeons have used bone cement laden with antibiot-ics during the re-implantation whereby the antibiotic contained in the cement or added to it is specific for the pathogen involved [5-7]. A prerequisite for this procedure is the isolation of the organism(s) The Pros and Cons of Trade Deficits and Surpluses The Pros and Cons of Trade Deficits and Surpluses By: OpenStaxCollege Because flows of trade always involve flows of financial payments, flows of international trade are actually the same as flows of international financial capital The question of whether trade deficits or surpluses are good or bad for an economy is, in economic terms, exactly the same question as whether it is a good idea for an economy to rely on net inflows of financial capital from abroad or to make net investments of financial capital abroad Conventional wisdom often holds that borrowing money is foolhardy, and that a prudent country, like a prudent person, should always rely on its own resources While it is certainly possible to borrow too much—as anyone with an overloaded credit card can testify—borrowing at certain times can also make sound economic sense For both individuals and countries, there is no economic merit in a policy of abstaining from participation in financial capital markets It makes economic sense to borrow when you are buying something with a longrun payoff; that is, when you are making an investment For this reason, it can make economic sense to borrow for a college education, because the education will typically allow you to earn higher wages, and so to repay the loan and still come out ahead It can also make sense for a business to borrow in order to purchase a machine that will last 10 years, as long as the machine will increase output and profits by more than enough to repay the loan Similarly, it can make economic sense for a national economy to borrow from abroad, as long as the money is wisely invested in ways that will tend to raise the nation’s economic growth over time Then, it will be possible for the national economy to repay the borrowed money over time and still end up better off than before One vivid example of a country that borrowed heavily from abroad, invested wisely, and did perfectly well is the United States during the nineteenth century The United States ran a trade deficit in 40 of the 45 years from 1831 to 1875, which meant that it was importing capital from abroad over that time However, that financial capital was, by and large, invested in projects like railroads that brought a substantial economic payoff (See the following Clear It Up feature for more on this.) 1/5 The Pros and Cons of Trade Deficits and Surpluses A more recent example along these lines is the experience of South Korea, which had trade deficits during much of the 1970s—and so was an importer of capital over that time However, South Korea also had high rates of investment in physical plant and equipment, and its economy grew rapidly From the mid-1980s into the mid-1990s, South Korea often had trade surpluses—that is, it was repaying its past borrowing by sending capital abroad In contrast, some countries have run large trade deficits, borrowed heavily in global capital markets, and ended up in all kinds of trouble Two specific sorts of trouble are worth examining First, a borrower nation can find itself in a bind if the incoming funds from abroad are not invested in a way that leads to increased productivity Several of the large economies of Latin America, including Mexico and Brazil, ran large trade deficits and borrowed heavily from abroad in the 1970s, but the inflow of financial capital did not boost productivity sufficiently, which meant that these countries faced enormous troubles repaying the money borrowed when economic conditions shifted during the 1980s Similarly, it appears that a number of African nations that borrowed foreign funds in the 1970s and 1980s did not invest in productive economic assets As a result, several of those countries later faced large interest payments, with no economic growth to show for the borrowed funds Are trade deficits always harmful? For most years of the nineteenth century, U.S imports exceeded exports and the U.S economy had a trade deficit Yet the string of trade deficits did not hold back the economy at all; instead, the trade deficits contributed to the strong economic growth that gave the U.S economy the highest per capita GDP in the world by around 1900 The U.S trade deficits meant that the U.S economy was receiving a net inflow of foreign capital from abroad Much of that foreign capital flowed into two areas of investment—railroads and public infrastructure like roads, water systems, and schools—which were important to helping the growth of the U.S economy The effect of foreign investment capital on U.S economic growth should not be overstated In most years the foreign financial capital represented no more than 6–10% of the funds used for overall physical investment in the economy Nonetheless, the trade deficit and the accompanying investment funds from abroad were clearly a help, not a hindrance, to the U.S economy in the nineteenth century A second “trouble” is: What happens if the foreign money flows in, and then ... As the debate over pornography and its place in society grows hotter every day, several authors in particular shed a new light on the subject. Both their intuition and insight involving their beliefs can help the reader a great deal in seeing aspects of this debate that might have otherwise gone without the consideration that they so deserve. I believe that pornography is not only okay, but is allowing our country to take a step back and ask ourselves how far we are willing to go and what we are willing to sacrifice in order to preserve free speech and our rights to personal choice. The argument over pornography is not merely the debate over right or wrong, but also involves the theory that its existence requires, or possibly even causes, an inequality between men and women. I ask you, how could something like pornography cause an in-equality between men and women when women are the major contributors to the industry? Who is going to watch a porn without women in it? Therefore, at least at first glance, it would seem that since women are actively contributing to the business of pornography maybe they should be criticized at least equally if not more so than the men who watch it. According to author J.M. Coetzee and his article "The Harms of Pornography", the real questions here are, "what is the difference between obscenity and pornography", and even more importantly, "where do we draw the line between the two"? Coetzee brings up a good point here. A point on which the entire debate over pornography hinges. What is the defenition of "obscenity"? An excerpt from a speech by Mike Godwin, Online Counsel for the Electronic Frontier Foundation, gives a good definition of obscenity in his on-line article: "Fear of Freedom: The Backlash Against Free Speech on the 'Net'". Everybody more or less knows something about what qualifies as obscene. You know it has something to do with "community standards," right? And with appealing to the "prurient interest." A work has to be a patently offensive depiction of materials banned by state statute and appeal to the prurient interest to be obscene and it also has to meet one other requirement. It also has to lack serious literary, artistic, social, political or scientific value. That's how something is classified as "obscene." Godwin states that one of the criteria for decency or absence of obscenity is that something must contain social political or scientific value. Is it possible that pornography is an outlet for people that prevents ideas that start out as fantasies or desires from becoming real? If so, then it's possible that the porn industry is doing us a bigger favor than we know.In an article written by Donna A. Demac, the history of censorship, obscenity, pornography and the rights of "the people" are conveyed with a decidedly liberal attitude. Demac's article gives an intelligent overview as to the actions of various political parties, groups and activists that have fought either for or against some of the issues regarding pornography, and his article can be effectively used to defend free speech.The most opinionated and conservative of the authors included is Catherine MacKinnon, who touches on the thought that there is a great deal of similarity between pornography and black slavery. In her article "Pornography, Civil Rights and Speech" she states that "the harm of pornography does not lie in the fact that it is COMM E N T ARY Open Access Pros and cons of estimating the reproduction number from early epidemic growth rate of influenza A (H1N1) 2009 Hiroshi Nishiura 1,2* , Gerardo Chowell 3,4 , Muntaser Safan 5 , Carlos Castillo-Chavez 3,6 * Correspondence: h.nishiura@uu.nl 1 PRESTO, Japan Science and Technology Agency, Honcho 4-1-8, Kawaguchi, Saitama, 332-0012, Japan Abstract Background: In many parts of the world, the exponential growth rate of infections during the initial epidemic phase has been used to make statistical inferences on the reproduction number, R, a summary measure of the transmission potential for the novel influenza A (H1N1) 2009. The growth rate at the initial stage of the epidemic in Japan led to estimates for R in the range 2.0 to 2.6, capturing the intensity of the initial outbreak among school-age children in May 2009. Methods: An updated estimate of R that takes into account the epidemic data from 29 May to 14 July is provided. An age-structured renewal process is employed to capture the age-dependent transmission dynamics, jointly estimating the reproduction number, the age-dependent susceptibility and the relative contribution of imported cases to secondary transmission. Pitfalls in estimating epidemic growth rates are identified and used for scrutinizing and re-assessing the results of our earlier estimate of R. Results: Maximum likelihood estimates of R using the data from 29 May to 14 July ranged from 1.21 to 1.35. The next-generation matrix, based on our age-structured model, predicts that only 17.5% of the population will experience infection by the end of the first pandemic wave. Our earlier estimate of R did not fully capture the population-wide epidemic in quantifying the next-generation matrix from the estimated growth rate during the initial stage of the pandemic in Japan. Conclusions: In order to quantify R from the growth rate of cases, it is essential that the selected model captures the underlying transmi ssion dynamics embedded in the data. Exploring additional epidemiological information will be useful for assessing the temporal dynamics. Although the simple concept of R is more easily grasped by the general public than that of the next-generation matrix, the matrix incorporating detailed information (e.g., age-specificity) is essential for reducing the levels of uncertainty in predictions and for assisting public health policymaking. Model-based prediction and policymaking are best described by sharing fundamental notions of heterogeneous risks of infection and death with non-experts to avoid potential confusion and/or possible misuse of modelling results. Background The reproduction number, R, the average number of secondary cases generated by a typical (or “average”) single primary case, of influenza A (H1N1) 2009 is a summary measure of the transmission potential in the population of interest. It has been Nishiura et al. Theoretical Biology and Medical Modelling 2010, 7:1 http://www.tbiomed.com/content/7/1/1 © 2010 Nishiura et al; licensee BioMed Central Ltd. This is an Open Access article distribute d under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which perm its unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. estimated using the early epidemic growth data in d ifferent locations across the world [1-12]. The estimations have been based primarily on models that include one or a limited number of aspects of heterogeneous transmission. The scientific community has been attracted to R because it provides a first aggregated measure of the overall transmissibility of an emerging infection [13]. Further, the estimate of R,basedon homogeneously or nearly homogeneously mixing population models that by design ignore most individual differences, is not only used to assess the initial growth of an epidemic but also the extent to which the population will ex perience infection by BÀI LUẬN TIẾNG ANH HAY THEO CHỦ ĐỀ BÀI LUẬN TIẾNG ANH HAY Nuclear energy Write about the pros and cons of using nuclear energy as a energy source. Nuclear fission or the splitting of the nucleus of an atom releases great amounts of energy, much more than any other conventional energy source. Nuclear energy has enormous potential as an energy source. There is almost limitless supply of energy. However, radioactive by- products and waste post serious health and environmental risks. The atomic or nuclear bomb is the uncontrolled release of nuclear energy. Thetremendous power and deadliness of this is evident when Hiroshima and Nagasaki was destroyed by atomic bombs at the end of World War II in 1945. The devastation was enormous, nothing like what human beings had seen before. it is not something to be repeated. Even so, the major powers of the world now possess enough atomic bombs to wipe out the entire population of the world. It is a chilling thought that human beings are now able to wipe themselves out. We can only hope that they have the sense not to. In a nuclear reactor, the release of nuclear energy is controlled. This energy is used for various purposes such as for generating electricity and driving submarines. However, the reactor has to be maintained carefully. An accident is potentially disastrous. The leakage of radioactive substances can cause death to living things and pollution of the environment, such as that which occurred at Chernobyl. As it is now, nuclear energy bolds enormous potential as an energy source but it is not totally safe to use. Perhaps one day, with more research and knowledge, human beings will learn how to harness nuclear energy safely. by-products something that is produced as a result of making something else tremendous very great in amount or level wipe out to destroy completely what is the pros and cons of publice transport? In today is society, it is a common sight to see more and more people using public transport. For many, this is a way to protect environment and relax during the way to an office. But there is a concern about crimes when public transport gets overcrowded. In this essay, I will discuss about both sides, following by what I think is right. Let is begin by looking at the upsides of using public transport. An increment of the number of passengers choosing buses, trolley cars and bullet trains means there will be a reduction of emissions and gases. Therefore, the air will be fresher and the global’s environment is protected. Another advantage is you have more time to relax. Instead of driving yourself to a company, a driver will do that for you. While sitting on a chair, you can entertain by listen to music, read a book or even sleep in case of you have busy works the previous day. Turning to the other side of the argument, crimes are a major problem. Many people think it is difficult to avoid pickpockets and robbers when board buses or trams. In the rush hour, a large number of passengers try to get in public transport as fast as possible is a big chance for those criminals. Although you know those are around, there is no way to keep your belongings safety while everybody is hurrying and trying to push, pull, break the queue. As a result, neither you board the bus nor keep the belongings. To sum up, using public transport is either good or bad choice depends on you. Using vehicles that environmentally friendly is a benefit, in contrast, the drawback is lost money. Personally, I strongly believe using public transport is still the best choice.  ... concerned about the health of these economies, 2/5 The Pros and Cons of Trade Deficits and Surpluses and quickly pulled their money out of stock and bond markets, real estate, and banks The extremely.. .The Pros and Cons of Trade Deficits and Surpluses A more recent example along these lines is the experience of South Korea, which had trade deficits during much of the 1970s and so was... out of stock and bond markets, real estate, and banks 4/5 The Pros and Cons of Trade Deficits and Surpluses Describe a scenario in which a trade surplus benefits an economy and one in which a trade