The prostate (from Greek προστάτης - prostates, literally "one who stands before", "protector", "guardian"[1]) is a compound tubuloalveolar exocrine gland of the male mammalian reproductive system. Women do not have a prostate gland, although women do have microscopic paraurethral Skene's glands connected to the distal third of the urethra in the prevaginal space that are homologous to the prostate. The main function of the prostate is to store and secrete a clear, slightly alkaline (pH 7.29) fluid that constitutes 10-30% of the volume of the seminal fluid that, along with spermatozoa, constitutes semen. The rest of the seminal fluid is produced by the two seminal vesicles. The alkalinity of seminal fluid helps neutralize the acidity of the vaginal tract, prolonging the lifespan of sperm. The prostatic part of the urethra develops from the pelvic (middle) part of the urogenital sinus (endodermal origin). Endodermal outgrowths arise from the prostatic part of the urethra and grow into the surrounding mesenchyme. The glandular epithelium of the prostate differentiates from these endodermal cells, and the associated mesenchyme differentiates into the dense stroma and the smooth muscle of the prostate. [2]The prostate glands represent the modified wall of the proximal portion of the male urethra and arises by the 9th week of embryonic life in the development of the reproductive system. Condensation of mesenchyme, urethra and Wolffian ducts gives rise to the adult prostate gland, a composite organ made up of several glandular and non-glandular components tightly fused within a common capsule. Within the prostate, the urethra coming from the bladder is called the prostatic urethra and merges with the two ejaculatory ducts. (The male urethra has two functions: to carry urine from the bladder during urination and to carry semen during ejaculation.) The prostate is sheathed in the muscles of the pelvic floor, which contract during the ejaculatory process. Benign prostatic hyperplasia (BPH) occurs in older men;[6] the prostate often enlarges to the point where urination becomes difficult. Symptoms include needing to go to the toilet often (pollakisuria) or taking a while to get started (hesitancy). If the prostate grows too large it may constrict the urethra and impede the flow of urine, making urination difficult and painful and in extreme cases completely impossible. BPH can be treated with medication, a minimally invasive procedure or, in extreme cases, surgery that removes the prostate. Minimally invasive procedures include Transurethral needle ablation of the prostate (TUNA) and Transurethral microwave thermotherapy (TUMT). These outpatient procedures may be followed by the insertion of a temporary Prostatic stent, to allow normal voluntary urination, without exacerbating irritative symptoms[7]. The surgery most often used in such cases is called transurethral resection of the prostate (TURP or TUR). In TURP, an instrument is inserted through the urethra to remove prostate tissue that is pressing against the upper part of the urethra and restricting the flow of urine. Older men often have corpora amylacea[8] (amyloid), dense accumulations of calcified proteinaceous material, in the ducts of their prostates. The corpora amylacea may obstruct the lumens of the prostatic ducts, and may underlie some cases of BPH. Prostate cancer is one of the most common cancers affecting older men in developed countries and a significant cause of death for elderly men (estimated by some specialists at 3%). Regular rectal exams are recommended for older men to detect prostate cancer early. In 1993, the Journal of the American Medical Association revealed a connection between vasectomy and an increased risk of prostate cancer. Reported studies of 48,000 and 29,000 men who had vasectomies showed 66 percent and 56 percent higher rates of prostate cancer, respectively. The risk increased with age and the number of years since the vasectomy was performed. However, in March of the same year, the National Institute of Child Health and Human Development held a conference cosponsored by the National Cancer Institute and others to review the available data and information on the link between prostate cancer and vasectomies. It was determined that an association between the two was very weak at best, and even if having a vasectomy increased one's risk, the risk was relatively small. Recent scientific breakthroughs have now meant using a Prostatic stent is a viable method of dis-obstructing the prostate. Stents are devices inserted into the urethra to widen it and keep it open. Stents can be temporary or permanent and is mostly done on an outpatient basis under local or spinal anesthesia and usually takes about 30 minutes.
In professional settings massage involves the client being treated while lying on a massage table, sitting upright in a massage chair, or lying on a pad on the floor. The massage subject may be fully, partly or unclothed and the body covered with towels or sheets. Specialized massage tables and chairs are used to position clients during massages. A typical commercial massage table has an easily cleaned, heavily padded surface, and a horseshoe-shaped head support that allows the client to breathe easily while lying face down and can be stationary or portable. An orthopedic pillow or bolster can be used to correct body positioning. Ergonomic chairs serve a similar function as a massage table. Chairs may be either stationary or portable models. Massage chairs are easier for the practitioner to transport than massage tables, and clients do not need to disrobe to receive a chair massage. Due to these two factors, chair massage is often performed in settings such as corporate offices, outdoor festivals, shopping malls, and other public locations. Many different types of oils can be used including fractionated coconut oil, grape seed oil, macadamia oil, sesame oil, pecan oil, and mustard oil. Arnica, from the flowers or leaves of the Arnica montana, may be added olive oil when used medicinally, or almond oil when used as a massage oil.[13] Aromatherapy oils such as neroli oil and pine oil can also be mixed with carrier oils. Ayurveda is a natural health care system originating in India that incorporates massage, yoga, meditation and herbal remedies. Ayurvedic massage, also known as Abhyanga is usually performed by one or two therapists using a heated blend of herbal oils based on the ayurvedic system of humors. Myofascial release refers to the manual massage technique for stretching the fascia and releasing bonds between fascia, integument, and muscles with the goal of eliminating pain, increasing range of motion and equilibrioception. Myofascial release usually involves applying shear compression or tension in various directions, or by skin rolling. Watsu is the combination of hydrotherapy and shiatsu developed by Harold Dull. The work is done in skin temperature water with both the therapist and practitioner in the water, usually a pool which is between 3.5 ft to 4 ft. (100–120�cm) deep. The work entails much movement in the water and practitioners believe that it incorporates the activation of the energy lines derived from shiatsu. Peer-reviewed medical research has shown that the benefits of massage include pain relief, reduced trait anxiety and depression, and temporarily reduced blood pressure, heart rate, and state anxiety.[19] Theories behind what massage might do include blocking nociception (gate control theory), activating the parasympathetic nervous system which may stimulate the release of endorphins and serotonin, preventing fibrosis or scar tissue, increasing the flow of lymph, and improving sleep[5] but such effects are yet to be supported by well designed clinical studies. In the USA licensure is the highest level of regulation and this restricts anyone without a license from practicing massage therapy or by calling themselves that protected title. Certification allows only those who meet certain educational criteria to use the protected title and registration only requires a listing of therapists who apply and meet an educational requirement. [34] People state that they use massage because they believe that it relieves pain from musculoskeletal injuries and other causes of pain, reduces stress and enhances relaxation, rehabilitates sports injuries, decreases feelings of anxiety and depression, and increases general well being.[5] Heinrich Himmler, commander of the Schutzstaffel (SS) and one of the most powerful men in Nazi Germany might have lost faith in German victory due to his discussions with his masseurs Felix Kersten and Walter Schellenberg.[38] Albert Bedane (1893–1980) who provided shelter to a Jewish woman and others during World War II was a massage/physiotherapist. Athletic training • Audiology • Bioengineering • Biomedical science • Chiropractic • Dental hygiene • Dietetics • Electrocardiographic technicians • Emergency medical services • Hemodialysis technicians • Massage therapy • Medical assistants • Medical physics • Medical technologist • Medical transcription • Music therapy • Nuclear medicine technology • Nutrition • Occupational therapy • Optometry • Phlebotomy • Orthotics/Prosthetics • Physical therapy • Podiatry • Psychology • Radiation therapy • Radiography • Radiologic technologist • Respiratory therapy • Speech therapy • Social work • Ultrasonography
An externality occurs when a decision causes costs or benefits to third party stakeholders, often, although not necessarily, from the use of a public good. In other words, the participants in an economic transaction do not necessarily bear all of the costs or reap all of the benefits of the transaction. For example, manufacturing that causes air pollution imposes costs on others when making use of public air. In a competitive market, this means too much or too little of the good may be produced and consumed in terms of overall cost or benefit to society, depending on incentives at the margin and strategic behavior. In the absence of significant externalities, parties to an economic transaction are assumed to benefit, improving the overall welfare of society. If third parties benefit substantially, such as in areas of education or safety, the good may be under-provided (or under-consumed); if costs to the public exceed costs to the economic decision makers, such as in pollution, the good may be over-provided, in terms of overall benefit or cost to society. Here, overall benefit and cost to society are defined as the collective economic utility for society. Economic theory considers any voluntary exchange to be mutually beneficial to both parties, for example a buyer and seller. Any exchange, however, can result in additional positive or negative effects on third parties. Those who suffer from external costs do so involuntarily, while those who enjoy external benefits do so at no cost. The left side of the chart (at right) shows externalities associated with consumption (such as the air pollution caused by driving), while the right side shows production externalities (such as water pollution from a car factory). In welfare economics, negative externalities result in an outcome that is not socially optimal. From the perspective of those affected, a negative externality is a problem (pollution from a factory), or a gain (honey bees that pollinate the garden). In the first case, the person who is affected by the negative externality in the case of air pollution will see it as lowered utility: either subjective displeasure or potentially explicit costs, such as higher medical expenses. The externality may even be seen as trespassing on their lungs, violating their property rights. Thus, an external cost may pose an ethical or political problem. Alternatively, it might be seen as a case of poorly-defined property rights, as with, for example, pollution of bodies of water that may belong to no-one (either figuratively, in the case of publicly-owned, or literally, in some countries and/or legal traditions). An external benefit, on the other hand, may increase the utility of third parties at no cost to them, which could be called "free lunch". Since the collective utility of society is improved but the direct participants have no way of monetizing the benefit, less of the good will be produced or consumed than would be optimal for society as a whole. Goods with positive externalities include education (believed to increase overall productivity and therefore well-being but widely disputed as these benefits of education can be considered as internalized) and health care (which may reduce the health risks and costs for third parties for such things as transmittable diseases). Positive externalities are frequently associated with the free rider problem. For example, individuals who are vaccinated reduce the risk of contracting the relevant disease for all others around them, and at high levels of vaccination, society may receive large health and welfare benefits; but any one individual can refuse vaccination, still avoiding the disease by "free riding" on the costs borne by others. There are a number of potential means of improving overall social utility when externalities are involved. The market-driven approach to correcting externalities is to "internalize" third party costs and benefits, for example, by requiring a polluter to repair any damage caused. In many cases, however, internalizing costs or benefits is not feasible or the true value cannot be determined. The values of the effects of the externality are difficult to quantify because they reflect the ethical views and preferences of the entire population. It may not be clear whose preferences are most important, interests may conflict, the value of externalities may be difficult to determine, and all parties involved may attempt to influence the policy responses to their own benefit. An example is the Externalities of Smoking, which can cost or benefit society depending on the situation. Because it may not be feasible to monetize the costs and benefits, another method is needed to either impose solutions or aggregate the choices of society, when externalities are significant. This may be through some form of representative democracy or other means. Political economy is, in broad terms, the study of the means and results of aggregating those choices and benefits that are not limited to purely private transactions. The usual economic analysis of externalities can be illustrated using a standard supply and demand diagram if the externality can be monetized and valued in terms of money. An extra supply or demand curve is added, as in the diagrams below. One of the curves is the private cost that consumers pay as individuals for additional quantities of the good, which in competitive markets, is the marginal private cost. The other curve is the true cost that society as a whole pays for production and consumption of increased production the good, or the marginal social cost. Similarly there might be two curves for the demand or benefit of the good. The social demand curve would reflect the benefit to society as a whole, while the normal demand curve reflects the benefit to consumers as individuals and is reflected as effective demand in the market. The harvesting by one fishing company in the ocean depletes the stock of available fish for the other companies and overfishing may result. This is an example of a common property resource, sometimes referred to as the Tragedy of the commons. A business may purposely underfund one part of their business, such as their pension funds, in order to push the costs onto someone else, creating an externality. Here, the "cost" is that of providing minimum social welfare or retirement income; economists more frequently attribute this problem to the category of moral hazards. Consumption by one consumer causes prices to rise and therefore makes other consumers worse off, perhaps by reducing their consumption. These effects are sometimes called "pecuniary externalities". Many economists do not accept the concept of pecuniary externalities, attributing such problems to anti-competitive behavior, monopoly power, or other definitions of market failures. Commonized costs of declining health and vitality caused by smoking and/or alcohol abuse. Here, the "cost" is that of providing minimum social welfare. Economists more frequently attribute this problem to the category of moral hazards, the prospect that a party insulated from risk may behave differently from the way they would if they were fully exposed to the risk. For example, an individual with insurance against automobile theft may be less vigilant about locking his car, because the negative consequences of automobile theft are (partially) borne by the insurance company. A beekeeper keeps the bees for their honey. A side effect or externality associated with his activity is the pollination of surrounding crops by the bees. The value generated by the pollination may be more important than the value of the harvested honey. An individual buying a product that is interconnected in a network (e.g., a video cellphone) will increase the usefulness of such phones to other people who have a video cellphone. When each new user of a product increases the value of the same product owned by others, the phenomenon is called a network externality or a network effect. Network externalities often have "tipping points" where, suddenly, the product reaches general acceptance and near-universal usage, a phenomenon which can be seen in the near universal take-up of cellphones in some Scandinavian countries. Knowledge spillover of inventions and information - once an invention (or most other forms of practical information) is discovered or made more easily accessible, others benefit by exploiting the invention or information. Copyright and intellectual property law are mechanisms to allow the inventor or creator to benefit from a temporary, state-protected monopoly in return for "sharing" the information through publication or other means. Sometimes the better part of a benefit from a good comes from having the option to buy something rather than actually having to buy it. A private fire department that only charged people that had a fire, would arguably provide a positive externality at the expense of an unlucky few. Some form of insurance could be a solution in such cases, as long as people can accurately evaluate the benefit they have from the option. As noted, externalities (or proposed solutions to externalities) may also imply political conflicts, rancorous lawsuits, and the like. This may make the problem of externalities too complex for the concept of Pareto optimality to handle. Similarly, if too many positive externalities fall outside the participants in a transaction, there will be too little incentive on parties to participate in activities that lead to the positive externalities. The graph below shows the effects of a positive or beneficial externality. For example, the industry supplying smallpox vaccinations is assumed to be selling in a competitive market. The marginal private benefit of getting the vaccination is less than the marginal social or public benefit by the amount of the external benefit (for example, society as a whole is increasingly protected from smallpox by each vaccination, including those who refuse to participate). This marginal external benefit of getting a smallpox shot is represented by the vertical distance between the two demand curves. Assume there are no external costs, so that social cost equals individual cost. If consumers only take into account their own private benefits from getting vaccinations, the market will end up at price Pp and quantity Qp as before, instead of the more efficient price Ps and quantity Qs. These latter again reflect the idea that the marginal social benefit should equal the marginal social cost, i.e., that production should be increased as long as the marginal social benefit exceeds the marginal social cost. The result in an unfettered market is inefficient since at the quantity Qp, the social benefit is greater than the societal cost, so society as a whole would be better off if more goods had been produced. The problem is that people are buying too few vaccinations. The issue of external benefits is related to that of public goods, which are goods where it is difficult if not impossible to exclude people from benefits. The production of a public good has beneficial externalities for all, or almost all, of the public. As with external costs, there is a problem here of societal communication and coordination to balance benefits and costs. This also implies that pollution is not something solved by competitive markets. The government may have to step in with a collective solution, such as subsidizing or legally requiring vaccine use. If the government does this, the good is called a merit good. One example is the phenomenon of "overeducation" (referring to post-secondary education) in the North American labour market. In the 1960s, many young middle-class North Americans prepared for their careers by completing a bachelor's degree. However, by the 1990s, many people from the same social mileu were completing master's degrees, hoping to "one up" the other competitors in the job market by signalling their higher quality as potential employees. By the 2000s, some jobs which had previously only demanded bachelor's degrees, such as policy analysis posts, were requiring master's degrees. Some economists argue that this increase in educational requirements was above that which was efficient, and that it was a misuse of the societal and personal resources that go into the completion of these master's degrees. Another example is the buying of jewelry as a gift for another person. In order for Person A to show that he values his spouse more than Person B values his spouse, Person A must buy his spouse more expensive jewelry than Person B buys. As in the first example, the cycle continues to get worse, because every actor positions himself/herself in relation to the other actors. Externalities can be resolved by agreement between the parties involved. The first, and most common type of agreement, is tacit agreement through the political process. Governments are elected to represent citizens and to strike political compromises between various interests. Normally governments pass laws and regulations to address pollution and other types of environmental harm. These laws and regulations can take the form of "command and control" regulation (such as setting standards, targets, or process requirements), or environmental pricing reform (such as ecotaxes or other pigovian taxes, tradable pollution permits or the creation of markets for ecological services. The second type of agreement is explicit agreement through bargaining. Ronald Coase argued that individuals could organize bargains so as to bring about an efficient outcome and eliminate externalities without government intervention. Some take this argument further, and make the political claim that government should restrict its role to facilitating bargaining among the affected groups or individuals and to enforcing any contracts that result. This result, often known as the Coase Theorem, requires that Thus, this theorem does not apply to the steel industry case discussed above. For example, with a steel factory that trespasses on the lungs of a large number of individuals with pollution, it is difficult if not impossible for any one person to negotiate with the producer, and there are large transaction costs. Hence the most common approach may be to regulate the firm (by imposing limits on the amount of pollution considered "acceptable") while paying for the regulation and enforcement with taxes. The case of the vaccinations also does not fit with the Coase Theorem. The firms of the vaccination industry would have to get together to bribe large numbers of people to have their shots. Individual firms would be tempted to "free ride" and not pay the cost of these bribes. The property rights involved are not well defined. This does not say that the Coase theorem is irrelevant. For example, if a logger is planning to clear-cut a forest in a way that has a negative impact on a nearby resort, the resort-owner and the logger could theoretically get together to agree to a deal. For example, the resort-owner could pay the logger not to clear-cut -- or could buy the forest. The most problematic situation, from Coase's perspective, occurs when the forest literally does not belong to anyone; the question of "who" owns the forest is not important, as any specific owner will have an interest in coming to an agreement with the resort owner (if such an agreement is mutually beneficial).
