Heavy traffic ahead: car culture accelerates.As the world's largest nation, China is drawing a lot of attention for its increased motorization mo·tor·ize tr.v. mo·tor·ized, mo·tor·iz·ing, mo·tor·iz·es 1. To equip with a motor. 2. To supply with motor-driven vehicles. 3. To provide with automobiles. rates. Although Chinas rate of automobile ownership Automobile ownership is the sum of all the aspects associated with owning an automobile. In developed countries owning an automobile has become very common because it is a widely available form of transportation. is low by the standards of the developed world, it is increasing at a very fast rate. Between the late 1970s and 2001, Chinas overall fleet of motor vehicles other than two-wheelers increased 10-fold, according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. an article in the 3 December 2003 issue of Energy far Sustainable Development Sustainable development is a socio-ecological process characterized by the fulfilment of human needs while maintaining the quality of the natural environment indefinitely. The linkage between environment and development was globally recognized in 1980, when the International Union . Along the way, the Chinese government Ever since Republic of China founded in January 1st, 1912, China has had several regional and national governments. List
China may be getting the lion's share of the attention, but people who follow international transportation issues say the trend in motorization is global. According to Daniel Sperling, a professor of engineering and environmental science and policy at the University of California, Davis The University of California, Davis, commonly known as UC Davis, is one of the ten campuses of the University of California, and was established as the University Farm in 1905. , and director of its Institute of Transportation Studies, motorization is soaring everywhere, with the fastest growth occurring in Asia and Latin America Latin America, the Spanish-speaking, Portuguese-speaking, and French-speaking countries (except Canada) of North America, South America, Central America, and the West Indies. . He says that the number of motor vehicles other than two-wheelers in the world is expected to double in the next 15 years to 1.3 billion. "The reason motorization is spreading so rapidly is that people value mobility," Sperling says. "But it's also happening because a lot of regions are growing economically. We use the rule of thumb that motorization takes off when per capita incomes Noun 1. per capita income - the total national income divided by the number of people in the nation income - the financial gain (earned or unearned) accruing over a given period of time reach about $5,000. And many parts of the world--many cities in China China is a geographical area encompassing multiple territories, under two states. You may be looking for:
Michael P. Walsh, a transportation and environmental consultant to governments in China and other developing countries, and author of the Energy for Sustainable Development article, believes there's another explanation. "Everybody, it seems to me, wants to follow the American model," he says. "We're held up as the country to emulate. It's an image that people have. If you're a modern country, you need to have lots of privately owned motor vehicles." Nobody doubts that there are benefits to increased mobility. But as Walsh points out, increasing numbers of automobiles and other motor vehicles in developing countries will result in deteriorating air quality, greater congestion The condition of a network when there is not enough bandwidth to support the current traffic load. congestion - When the offered load of a data communication path exceeds the capacity. , and poorer quality of life. It also means greater energy consumption--and for an enormously populated pop·u·late tr.v. pop·u·lat·ed, pop·u·lat·ing, pop·u·lates 1. To supply with inhabitants, as by colonization; people. 2. nation like China, which is moving rapidly and steadily toward a position of international power, the implications of growing reliance on foreign oil sources can't be ignored. Impacts of Increased Motorization Halfway during a recent talk on the current state of urban transportation in developing countries, Massachusetts Institute of Technology Massachusetts Institute of Technology, at Cambridge; coeducational; chartered 1861, opened 1865 in Boston, moved 1916. It has long been recognized as an outstanding technological institute and its Sloan School of Management has notable programs in business, urban planning urban planning: see city planning. urban planning Programs pursued as a means of improving the urban environment and achieving certain social and economic objectives. professor Ralph Gakenheimer turned to a series of slides to illustrate a point. "I'm about to tell you how to ride a bicycle in Shanghai when you're making a left turn," he told his audience. "This is only for the courageous listener." The slides showed extremely heavy traffic on a two-way Shanghai street Shanghai Street is a street in Hong Kong, passing through Yau Ma Tei and Mong Kok in Kowloon. It starts at Austin Road in the south, and ends at Lai Chi Kok Road in the north. It runs parallel to Nathan Road, Temple Street and Reclamation Street. divided into four lanes. Motorized mo·tor·ize tr.v. mo·tor·ized, mo·tor·iz·ing, mo·tor·iz·es 1. To equip with a motor. 2. To supply with motor-driven vehicles. 3. To provide with automobiles. vehicles occupied the inner lanes, bumper to bumper, while a dense throng of bicyclists filled the outer lanes. The Chinese system of segregating vehicles into lanes shared by similar machines is sensible to a point, Gakenheimer told the audience, but what happens if you're a bicyclist in the outer lane and you want to take a left at the next intersection? His series of slides provided the answer. When the traffic halts at a red light, left-turning bicyclists insinuate in·sin·u·ate v. in·sin·u·at·ed, in·sin·u·at·ing, in·sin·u·ates v.tr. 1. To introduce or otherwise convey (a thought, for example) gradually and insidiously. See Synonyms at suggest. 2. themselves in front of the automobiles traveling in the same direction so that when the light turns green they can dart diagonally across the intersection to their assigned lane, cutting off the automobiles coming from the opposite direction--until the automobiles force their way into the intersection to halt the bicyclists. Similar melees occur throughout China, Gakenheimer says, because the numbers of cars and other motor vehicles on the nation's roadways have been skyrocketing in recent years with no slowdown in sight. And as cars have come into repeated conflict with bicycles, increasing numbers of cities in China are taking a step that many environmentalists find troubling. "All over China, municipal governments have begun to suppress or prohibit the use of bicycles in certain places," Gakenheimer says. "As you might imagine, this is a big controversy. Many [environmentalists] are outraged that anyone would trammel on something so affordable and environmentally sustainable as bicycles." The impact of increased motorization on Chinese urban air quality is still difficult to determine, Walsh says. Chinese cities have tended to have poor air quality for years, so the appearance of more motor vehicles isn't exactly creating a new pollution problem. Instead, he says, Chinese cities are undergoing a shift from industrial pollution to motor vehicle pollution. At the same time that motor vehicles have begun to clog city thoroughfares, industry has been moving out to urban peripheries. This shift means that sulfur dioxide sulfur dioxide, chemical compound, SO2, a colorless gas with a pungent, suffocating odor. It is readily soluble in cold water, sparingly soluble in hot water, and soluble in alcohol, acetic acid, and sulfuric acid. levels have been going down in Chinese city air, but they are being replaced by vehicle emissions including carbon monoxide carbon monoxide, chemical compound, CO, a colorless, odorless, tasteless, extremely poisonous gas that is less dense than air under ordinary conditions. It is very slightly soluble in water and burns in air with a characteristic blue flame, producing carbon dioxide; and ozone-forming nitrogen oxides Noun 1. nitrogen oxide - any of several oxides of nitrogen formed by the action of nitric acid on oxidizable materials; present in car exhausts pollutant - waste matter that contaminates the water or air or soil . While China has greatly tightened requirements for new vehicles, the older cars on the nation's roadways create serious pollution problems. According to the Energy Foundation, a partnership of Chinese and U.S. foundations interested in sustainable energy
Sustainable energy sources are energy sources which are not expected to be depleted in a timeframe relevant to the human race, and which , recent testing shows that emission levels of Chinese autos are similar to those of cars used in the United States in the late 1960s and early 1970s; these cars emit 10-20 times more pollution than cars currently used in Western countries. According to the foundation, 40% of autos and 70% of taxis in Beijing fail to meet the most basic Western emission standards Emission standards are requirements that set specific limits to the amount of pollutants that can be released into the environment. Many emission standards focus on regulating pollutants released by automobiles (motor cars) and other powered vehicles but they can also regulate . Increased motorization in the developing world is having social and cultural impacts on poorer societies as well. At the same time that people from rural areas continue to flood into already densely populated cities to find jobs, people whose incomes have risen to the point where they can buy cars are fleeing to the cities' outskirts in a manner not unlike the suburbanization of American cities following World War II. The upper middle class in China already sees the car as a way to provide them more mobility, says Lee Schipper, director of research at the World Resources Institute's Center for Transport and the Environment (EMBARQ) in Washington, D.C. "But the resulting congestion when [just] twenty percent of the daily journeys are in cars--the case in Mexico City Mexico City Spanish Ciudad de México City (pop., 2000: city, 8,605,239; 2003 metro. area est., 18,660,000), capital of Mexico. Located at an elevation of 7,350 ft (2,240 m), it is officially coterminous with the Federal District, which occupies 571 sq mi or Sao Paulo today--means that nobody has more mobility." "It's not that cars and two-wheelers are bad," Schipper adds. "The problem is that they're being put on the crowded streets so fast, everywhere, and authorities aren't doing anything about it. There are too many of them, too soon. You can't keep up." In addition to rising air pollution, the glut glut pronounced as rut, slut Vox populi An excess of a service or skilled labor in a particular area. See Physician glut. of traffic means accident rates are high, with pedestrians and cyclists This is an incomplete list. Please add to this list if you are aware of an omission. This is a list of cyclists by decade. Cyclists by decade Cyclists before the 1880s
abbr. 1. effective horsepower 2. electric horsepower 112:A628-A631 (2004).] Gakenheimer notes a further pernicious pernicious /per·ni·cious/ (per-nish´us) tending toward a fatal issue. per·ni·cious adj. Tending to cause death or serious injury; deadly. effect on the individual. Public transit is the form of transportation most impacted by congestion; autos can take circuitous cir·cu·i·tous adj. Being or taking a roundabout, lengthy course: took a circuitous route to avoid the accident site. routes or select more accessible destinations, whereas city buses are confined to predetermined pre·de·ter·mine v. pre·de·ter·mined, pre·de·ter·min·ing, pre·de·ter·mines v.tr. 1. To determine, decide, or establish in advance: routes. And the greater the congestion, the more tempting it is to get a car. So there is what he calls a "tragedy of the commons The Tragedy of the Commons is a type of social trap, often economic, that involves a conflict over resources between individual interests and the common good. The "Tragedy of the Commons" is a structural relationship between free access to, and unrestricted demand for a " effect. The effects of motorization on public transit was one of the topics covered in an article by Sperling and Eileen Claussen, president of the Pew Center on Global Climate Change The Pew Center on Global Climate Change is a non-profit advocacy organization that was established in 1998. Its Board of Directors includes Kenneth Arrow and Klaus Töpfer. [1] It is supported by The Pew Charitable Trusts, which "is working to create a policy environment , published in the spring 2004 issue of Access magazine. They pointed out that increased motorization also includes an explosion in two-wheel motorized vehicles in many countries, pulling riders and revenue away from public-transit systems (and, Schipper notes, clogging the streets in Asia the way cars and mini-buses do in Latin America). As a result, wrote Claussen and Sperling, "In nearly all cities worldwide, public transit is losing market share." The outcome in poor, densely populated cities with limited roadways for motor vehicles has been "far worse traffic congestion and pollution than exist in the United States," wrote Sperling and Claussen, despite the fact that these cities have a fraction of the car ownership of the United States. They pointed out that the challenge of building roadways is more than just a question of economics and financing. "Only a small minority of people in the developing world own cars and benefit from massive road-building budgets," they wrote. "In contrast, the vast majority suffer from increasing traffic congestion, noise, and pollution." Perhaps worse, says Gakenheimer, is that this majority suffers from the separation of destinations available only to auto users--a general fragmentation of society and destination opportunities. The Governmental Influence In China, a bastion of orthodox socialism not that long ago, the transition is especially jarring. In the old, purely socialist days, says Gakenheimer, the emphasis was on clustering workers, jobs, and services closely together. People lived close to their work, with commercial and business services nearby. But with the liberalization lib·er·al·ize v. lib·er·al·ized, lib·er·al·iz·ing, lib·er·al·iz·es v.tr. To make liberal or more liberal: "Our standards of private conduct have been greatly liberalized . . . of the land market since the 1980s, that all changed. For example, Gakenheimer says, people realized that making bicycles in the commercial center of the city had become a poor use of land, so they moved those facilities to urban peripheries where land was cheaper and they'd have more room. Then they sold the former space to buyers who used it for commercial and office use more district. "What this does is enormously increase the journey to work of the bicycle makers and also tends to create a central business district where there really wasn't one before," he says. "And the new central business district creates enormous radial commuting trip requirements." Another factor accelerating the pace of urban decentralization de·cen·tral·ize v. de·cen·tral·ized, de·cen·tral·iz·ing, de·cen·tral·iz·es v.tr. 1. To distribute the administrative functions or powers of (a central authority) among several local authorities. in China, Gakenheimer says, is the fact that private land ownership doesn't exist there. Land in China is owned either by the state or by collectives, and the government has constitutionally backed power to "requisition A written demand; a formal request or requirement. The formal demand by one government upon another, or by the governor of one state upon the governor of another state, of the surrender of a fugitive from justice. The taking or seizure of property by government. " any land whenever it sees fit. As a result, Gakenheimer says, the suburbia that characterizes the United States is sprouting quickly in China. And as the new China begins to resemble the United States and Europe in many ways, its leaders perceive the private motor vehicle as an integral commodity. Moreover, he says, Chinese cities collect the revenue from urbanization only at the beginning of long leases. As a result, they must continue to induce urbanization to have a continual revenue stream. But to characterize the Chinese government as being blind to the dangers of rapid motorization is inaccurate. In 2000, China banned leaded gasoline and adopted the Euro I emission standards that were enacted in Europe in the early 1990s for all new cars and trucks. Last year, the Chinese adopted the Euro II standards enacted in Europe in the mid-1990s. Some cities are going further. Walsh says that Beijing, for example, will soon require the Euro III standards, which were adopted in 2001 in Europe. Meanwhile, China has created its first fuel economy standards for new cars, which go into effect in July 2005. In the United States, cars are required to achieve at least 27.2 miles per gallon Noun 1. miles per gallon - the distance traveled in a vehicle powered by one gallon of gasoline or diesel fuel unit, unit of measurement - any division of quantity accepted as a standard of measurement or exchange; "the dollar is the United States unit of (mpg) while SUVs and light trucks are counted under a different system (and different agency) and meet a far more lenient le·ni·ent adj. Inclined not to be harsh or strict; merciful, generous, or indulgent: lenient parents; lenient rules. standard. In China, the new standards place an absolute floor on fuel economy for cars according to their weight class (there are 15 classes in China). The average weight of cars sold in China in 2003 was more than 3,000 pounds, large by developing country standards. The Chinese standards cannot prevent overall mileage from deteriorating if weight increases, Schipper says, but they may discourage manufacturers from making heavier cars that cannot meet standards for their weight classes. Schipper says that while the speed with which China has implemented fuel standards is laudable laud·a·ble adj. Healthy; favorable. , even more noteworthy is the fact that China is aspiring to Western standards even though its economy, on a per capita [Latin, By the heads or polls.] A term used in the Descent and Distribution of the estate of one who dies without a will. It means to share and share alike according to the number of individuals. basis, is still far from Western levels. "But the question is whether these measures will be swamped by the overall increase in motorization," he says. "And I don't have the answer to that." Sperling says the escalation of motor vehicles in developing countries will only continue unless the governments in those countries intervene to halt--or at least slow down--the march to a U.S.-style transportation system featuring many personal vehicles. "The market forces are such that unless government intervenes, countries will follow that path because the elites buy the cars, the elites run the government and industry, so there's a lot of pressure to build more roads," he says. "It creates a spiral of more and more motorization, and it takes tremendous political leadership not to follow that path." The Role of the Automakers In 2004, a group of international automotive and energy companies known as the World Business Council for Sustainable Development The World Business Council for Sustainable Development (WBCSD) is a CEO-led, global association of some 200 companies dealing exclusively with business and sustainable development. issued a report called Mobility 2030." Meeting the Challenges to Sustainability, which detailed recommendations for achieving "sustainable mobility" on a global scale. The report defines sustainable mobility as the ability to meet the needs of society to move freely, gain access, communicate, trade, and establish relationships without sacrificing other essential human or ecological values today or in the future. Martin Wachs, director of the Institute of Transportation Studies at the University of California, Berkeley The University of California, Berkeley is a public research university located in Berkeley, California, United States. Commonly referred to as UC Berkeley, Berkeley and Cal , served as a reviewer on the project and came away from it struck by the sense of responsibility that the companies seem to hold toward auto growth in developing countries: "They acknowledged that worldwide adoption of the automobile is an environmental threat, and they are considering collectively what industries might do to create a sustainable transition to a more 'automobilized' world," he says. Wachs doesn't believe that the report succeeds in making a convincing case for global automotive sustainability. What's significant, though, is that it took place at all, he says. "What it represents," he says, "is an awakening of industries, which just a few years ago might have said, 'This isn't our responsibility; our responsibility is to our shareholders.' But now they're saying that they do have responsibilities and they should be thinking in terms of fuel cells and other more energy-efficient forms of powering automobiles. So I think that's reason to have a little bit of optimism." Mobility 2030 outlines seven goals that the council believes must be met in order to achieve automotive sustainability: (1) reduce conventional vehicle emissions "so that they do not constitute a significant public health concern anywhere in the world"; (2) limit greenhouse gas greenhouse gas n. Any of the atmospheric gases that contribute to the greenhouse effect. greenhouse gas emissions to sustainable levels by moving toward hydrogen and bio-based fuels; (3) significantly reduce the number of traffic-related deaths and injuries worldwide; (4) reduce traffic noise; (5) reduce traffic congestion; (6) narrow "mobility divides" between rich and poor people within countries, as well as between rich and poor countries, by improving access to transportation for poor people in rural areas; and (7) improve mobility opportunities for the general population so that people don't need to rely on privately owned vehicles. Sperling agrees that automakers seeking to take advantage of expanding markets in the developing world have a responsibility to ease the impacts of their products on poor societies. He also believes that private investment can be a strong tool in developing innovative transportation strategies in developing countries. Private investment, he says, and not government, accounts for most of the resources that flow from industrial to developing countries. He suggested that the Overseas Private Investment Corporation, a development agency created by the U.S. government in 1971, might create a public-private investment fund specifically targeting transportation needs in developing countries. Schipper recently attended the 2004 Challenge Bibendum in Shanghai. This yearly meeting Members of the Religious Society of Friends, or Quakers, use the term Yearly Meeting to refer to an organization composed of a collection of smaller, more frequent constituent meetings within a geographical area. is attended by all the major car manufacturers and sponsored by Michelin. Schipper says he noticed the same kind of attention to the problem of global motorization that the World Business Council of Sustainable Development recognized in its Mobility 2030 report. "They were more than willing to play ball on the clean air side," he says. "But no individual company sees an upper limit on the number of cars that can circulate. The reality, though, is that there isn't going to be a car in every garage because there isn't going to be room for the garage--or the car." Sensible Responses Not all of the news about the invasion of cars and other motorized vehicles into the developing world is dire. In fact, there are several examples of strong governmental leadership taking action to soften the blow of motorization. The island nation of Singapore has made auto ownership prohibitively expensive through the imposition of various fees, including one that must be paid just to enter an auction for a limited number of auto stickers. People who win the stickers at auction must then pay for the vehicle itself. Singapore also has an extensive public transportation system that provides access to almost everywhere on the island. Bogota, Colombia, has built an extremely successful bus rapid transit
BRT Business Roundtable BRT Brightness BRT Be Right There (chat) BRT Bruttoregistertonnen (German: Gross Register Tons) BRT Biratnagar (Nepal) ) system, Transmilenio, which employs large, modern buses on a dedicated thoroughfare THOROUGHFARE. A street or way so open that one can go through and get out of it without returning. It differs from a cul de sac, (q.v.) which is open only at one end. 2. Whether a street which is not a thoroughfare is a highway, seems not fully settled. that cuts directly through the middle of the city. According to Schipper, 5-10% of Transmilenio's passengers are former auto users--a huge number in any new public transit system, he says. The success of Bogota's BRT system and an earlier one, the pioneering BRT system in Curitiba, Brazil, in the 1970s, has drawn significant attention around the world, including the developed world. Cities that have adopted such systems include Kunming, Delhi, Los Angeles Los Angeles (lôs ăn`jələs, lŏs, ăn`jəlēz'), city (1990 pop. 3,485,398), seat of Los Angeles co., S Calif.; inc. 1850. , Dublin, Paris, and most large cities in Latin America. Shanghai is currently building a BRT system and an extensive subway system with help in part from EMBARQ. And Shanghai has long imposed disincentives and restrictions on auto use, such as stiff registration fees. Still another tactic being contemplated to reduce auto congestion in developing countries actually originated in the developed world, in the city of London, England, which pioneered the concept of "congestion pricing." In 2003, London initiated a congestion-pricing program in which drivers had to pay a fee of 5 [pounds sterling] (about US$8) to cross a clearly marked boundary in the center city. The effect has been reduced congestion and increased public transit ridership rid·er·ship n. The number of passengers who ride a public transport system. . The fee will rise soon, says Schipper, and the area where it is payable will expand. Luis Gutierrez, who oversees EMBARQ's Latin American programs, says he has been talking about a congestion pricing program with officials in Sao Paolo, one of three Latin American cities in which EMBARQ is working to create public--private partnerships for sustainable transportation. "These kinds of policies are very simple for people to understand," he says. "You have limited public space and a lot of demand." He says the idea enjoys growing public support, and city officials like it, too, because it could provide an additional source of revenue. There's just one problem, he says: the people who own the cars--and who want to drive anywhere for as little cost as possible--are middle class, and the middle is politically powerful. Gutierrez also says the idea of BRT systems modeled after Bogota has become extremely popular. In 10 years, he says, Latin America will have 99 cities with populations of at least 750,000 and a total of 8,000 kilometers of heavily traveled corridors suitable for BRT systems. Gutierrez says the problem of rapidly increasing motorization is the same everywhere, and that governments in Latin America are responding to privately owned cars in much the same way that Asian governments are. They see them as contributors to economic development--or at least as a sign of it. But Gutierrez senses that pressure is building from a public that is growing tired of increased congestion, rising air pollution, and too many traffic accidents. Furthermore, he believes another change may be occurring. "I think that the middle class, who think having a car is equivalent to freedom, are having to modify their thoughts," he says. "They're finding the reality is that having a private car doesn't mean they have the freedom to move from one place to another very fast." But increasing traffic congestion itself is a testament to the strength of demand for ownership of one's own car, just like in the United States. Sperling says that developing countries and cities often lack the money, expertise, and political will to tackle the problem. "There are a lot of tools available--BRT, car sharing, even congestion pricing," he says. "But they're all difficult to implement. You have pricing, land use management, different ways of organizing public transport. But none of them are easy to do." In Sperling and Claussen's Access article, they presented the case for stronger U.S. action to help developing countries achieve sustainable transportation strategies through various kinds of loans, foundation support for sending U.S. experts to assist governments in developing countries, educational programs, and the involvement of the automotive and energy industries, who have significant stakes in the long-term outcome of global motorization. They argued that the U.S. withdrawal from the Kyoto Protocol Kyoto Protocol: see global warming. has undermined American credibility that the nation is serious about the issue of greenhouse gases. And while the United States can do a great deal to foster sound sustainable transportation programs in other countries, they suggested that it could exert far more global influence by pushing for laws to reduce greenhouse gas emissions in U.S. cars, because, they wrote, the United States "to a large degree drives the pace and direction of technology development worldwide." They concluded their article by sounding an alarm: "(T)here can be no doubt that the developing world is racing to repeat the developed world's transportation history. There can be no doubt that the undesirable effects associated with that history will mitigate the many associated benefits." As motor vehicles proliferate pro·lif·er·ate v. To grow or multiply by rapidly producing new tissue, parts, cells, or offspring. in the developing world, the challenge of achieving an acceptable trade-off between economic benefits and environmental impacts is formidable. "There's reason to be hopeful," says Wachs. "But as the automobile becomes much more standard in places like India and China, the threat to a sustainable environment is substantial."
Average Annual Growth
Rates
2000-2030 2000-2050
Total 1.6% 1.7%
Africa 1.9% 2.1%
Latin America 2.8% 2.9%
Middle East 1.9% 1.8%
India 2.1% 2.3%
Other Asia 1.7% 1.9%
China 3.0% 3.0%
Eastern Europe 1.6% 1.8%
Former Soviet Union 2.2% 2.0%
OECD Pacific 0.7% 0.7%
OECD Europe 1.0% 0.8%
OECD North America 1.2% 1.1%
Bocskay KA, Tang D, Orjuela MA, Liu X, Warburton DP, Perera FP. 2005. Chromosomal aberrations in cord blood cord blood n. Blood present in the umbilical vessels at the time of delivery. are associated with prenatal prenatal /pre·na·tal/ (-na´tal) preceding birth. pre·na·tal adj. Preceding birth. Also called antenatal. prenatal preceding birth. exposure to carcinogenic carcinogenic having a capacity for carcinogenesis. poly-cyclic aromatic hydrocarbons. Cancer Epidemiol Biomarkers Prev 14:506-511. |
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