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1.
Anthropometric measures including height provide an indication of childhood health that allows exploration of relationships between early life circumstances and adult health. Height can also be used to provide some indication of how early life health is related to selection of migrants and the Hispanic paradox in the United States. This article joins information on persons of Mexican nativity ages 50 and older in the United States collected in the National Health and Nutrition Examination Survey IV (NHANES IV 1999-2002) with a national sample of persons of the same age living in Mexico from the Mexican Health and Aging Survey (MHAS 2001) to examine relationships between height, education, migration, and late-life health. Mexican immigrants to the United States are selected for greater height and a high school, rather than higher or lower, education. Return migrants from the United States to Mexico are shorter than those who stay. Height is related to a number of indicators of adult health. Results support a role for selection in the Hispanic paradox and demonstrate the importance of education and childhood health as determinants of late-life health in both Mexico and the United States.  相似文献   

2.
Abstract

The prospects for deep seabed mining in this century appear remote. The U.N. Convention on the Law of the Sea was closed for signature on December 10, 1982. As of that date, 155 nation‐states and four entities had signed, but not the United States and some others. Since that time, the United States has endeavored without much success to develop a “Reciprocating States Agreement”; that would legitimate seabed mining with or without the U.N. Convention. On the other hand, the Preparatory Commission has met six times and is making only modest progress without the participation of the United States, the United Kingdom, and the Federal Republic of Germany.  相似文献   

3.
The dramatic growth of research and development activities in the pharmaceutical sector in emerging economies raises the question of whether the United States still keeps its dominant role in the global pharmaceutical innovation landscape. This paper focuses on investigating the role of the United States in global pharmaceutical innovation, and differs from previous studies by shifting attention to a network analytic perspective to track the global distribution of pharmaceutical inventions. Our sample is composed of key patents covering all new drugs approved by the Food and Drug Administration between 1996 and 2010. The results show that the United States still dominates in the global pharmaceutical innovation network, especially when it comes to essential core inventions. However, the United States shows a slightly decreasing prominence in the networks of either total new drugs or New Molecular Entity (NME) drugs in the time period 2006–2010 as compared to previous time periods, revealed by subtle traces of network centralities.  相似文献   

4.
While the Atlantic Coast of the United States and Canada is a major wintering area for sea ducks, knowledge about their wintering habitat use is relatively limited. Black Scoters have a broad wintering distribution and are the only open water species of sea duck that is abundant along the southeastern coast of the United States. Our study identified variables that affected Black Scoter (Melanitta americana) distribution and abundance in the Atlantic Ocean along the southeastern coast of the United States. We used aerial survey data from 2009 to 2012 provided by the United States Fish and Wildlife Service to identify variables that influenced Black Scoter distribution. We used indicator variable selection to evaluate relationships between Black Scoter habitat use and a variety of broad‐ and fine‐scale oceanographic and weather variables. Average time between waves, ocean floor slope, and the interaction of bathymetry and distance to shore had the strongest association with southeastern Black Scoter distribution.  相似文献   

5.
R J McKendry  G A Wells  P Dale  O Adam  L Buske  J Strachan  L Flor 《CMAJ》1996,154(2):171-181
OBJECTIVE: To determine whether location of postgraduate medical training and other factors are associated with the emigration of physicians from Canada to the United States. DESIGN: Case-control study, physicians were surveyed with the use of a questionnaire mailed in May 1994 (with a reminder sent in September 1994), responses to which were accepted until Dec. 31, 1994. PARTICIPANTS: Physicians randomly selected from the CMA database, 4000 with addresses in Canada and 4000 with current addresses in the United States and previous addresses in Canada. OUTCOME MEASURES: Sex, age, location of undergraduate and postgraduate medical training, qualifications, practice location, opinions concerning residence decisions, current satisfaction and plans. RESULTS: The overall response rate was 49.6% (50.0% among physicians in the United States and 49.2% among those in Canada). Age and sex distributions were similar among the 8000 questionnaire recipients and the nearly 4000 respondents. Physicians living in the United States were more likely to be older (mean 53.2 v. 49.6 years of age), male (87% v. 75%) and specialists (79% v. 52%) than those practising in Canada. Postgraduate training in the United States was associated with subsequent emigration (odds ratio 9.2, 95% confidence interval 7.8 to 10.7). However, in rating the importance of nine factors in the decision to emigrate or remain in Canada, there was no significant difference between the two groups in the rating assigned to location of postgraduate training. Professional factors rated most important by most physicians in both groups were professional/clinical autonomy, availability of medical facilities and job availability. Remuneration was considered an equally important factor by those in Canada and in the United States. Six of seven personal/family factors were rated as more important to their choice of practice location by respondents in Canada than by those in the United States. Current satisfaction was significantly higher among respondents in the United States. Most physicians in each group planned to continue practising at their current location. Of Canadian respondents, 22% indicated that they were more likely to move to the United States than they were a year beforehand, whereas 4% of US respondents indicated that they were more likely to return to Canada. CONCLUSIONS: Factors affecting the decision to move to the United States or remain in Canada can be categorized as "push" factors (e.g., government involvement) and "pull" factors (e.g., better geographic climate in the US). Factors can also be categorized by whether they are amenable to change (e.g., availability of medical facilities) or cannot be managed (e.g., proximity of relatives). An understanding of the reasons why physicians immigrate to the United States or remain in Canada is essential to planning physician resources nationally.  相似文献   

6.
Aim Substantial overlap in the climate characteristics of the United States and China results in similar land‐cover types and weather conditions, especially in the eastern half of the two countries. These parallels suggest similarities in fire regimes as well, yet relatively little is known about the historical role of fire in Chinese ecosystems. Consequently, we aimed to infer fire regime characteristics for China based on our understanding of climate–fire relationships in the United States. Location The conterminous United States and the People's Republic of China. Methods We used generalized additive models to quantify the relationship between reference fire regime classes adopted by the LANDFIRE initiative in the United States, and a global climate data set. With the models, we determined which climate variables best described the distribution of fire regimes in the United States then used these models to predict the spatial distribution of fire regimes in China. The fitted models were validated quantitatively using receiver operating characteristic area under the curve (AUC). We validated the predicted fire regimes in China by comparison with palaeoecological fire data and satellite‐derived estimates of current fire activity. Results Quantitative validation using the AUC indicated good discrimination of the distribution of fire regimes by models for the United States. Overall, fire regimes with more frequent return intervals were more likely in the east than in the west. The resolution of available historical and prehistorical fire data for China, including sediment cores, allowed only coarse, qualitative validation, but provided supporting evidence that fire has long been a part of ecosystem function in eastern China. MODIS satellite data illustrated that fire frequency within the last decade supported the classification of much of western China as relatively fire‐free; however, much of south‐eastern China experiences more fire activity than predicted with our models, probably as a function of the extensive use of fire by people. Conclusions While acknowledging there are many cultural, environmental and historical differences between the United States and China, our fire regime models based on climate data demonstrate potential historical fire regimes for China, and propose that large areas of China share historical fire–vegetation–climate complexes with the United States.  相似文献   

7.

Introduction

The Centers for Disease Control and Prevention is considering implementation of overseas medical screening of student-visa applicants to reduce the numbers of active tuberculosis cases entering the United States.

Objective

To evaluate the costs, cases averted, and cost-effectiveness of screening for, and treating, tuberculosis in United States-bound students from countries with varying tuberculosis prevalence.

Methods

Costs and benefits were evaluated from two perspectives, combined and United States only. The combined perspective totaled overseas and United States costs and benefits from a societal perspective. The United States only perspective was a domestic measure of costs and benefits. A decision tree was developed to determine the cost-effectiveness of tuberculosis screening and treatment from the combined perspective.

Results

From the United States only perspective, overseas screening programs of Chinese and Indian students would prevent the importation of 157 tuberculosis cases annually, and result in $2.7 million in savings. From the combined perspective, screening programs for Chinese students would cost more than $2.8 million annually and screening programs for Indian students nearly $440,000 annually. From the combined perspective, the incremental cost for each tuberculosis case averted by screening Chinese and Indian students was $22,187 and $15,063, respectively. Implementing screening programs for German students would prevent no cases in most years, and would result in increased costs both overseas and in the United States. The domestic costs would occur because public health departments would need to follow up on students identified overseas as having an elevated risk of tuberculosis.

Conclusions

Tuberculosis screening and treatment programs for students seeking long term visas to attend United States schools would reduce the number of tuberculosis cases imported. Implementing screening in high-incidence countries could save the United States millions of dollars annually; however there would be increased costs incurred overseas for students and their families.  相似文献   

8.
Although most provisions of the United Nations Convention on the Law of the Sea are regarded customary international law and the United States views most of its provisions as such, the outsider status of the United States causes problems in some areas, especially concerning the continental shelf beyond 200 nautical miles. This article asks whether it is possible for the United States to establish the outer limits of its continental shelf beyond 200 nautical miles in line with international law without becoming a state party to the convention, and if that is possible, how could the United States proceed?  相似文献   

9.
中国和美国大豆疫霉群体遗传结构的ISSR分析   总被引:12,自引:0,他引:12  
为探究中国和美国大豆疫霉的遗传关系, 采用简单序列重复区间扩增多态性(ISSR)技术, 对来自中国黑龙江省、福建省和美国的3个大豆疫霉地理群体的遗传多样性进行了分析。通过13个ISSR引物对供试的111株大豆疫霉菌株进行扩增, 共得到102个ISSR条带, 其中多态性条带为88个, 占86%。遗传变异分析表明, 美国群体具有更高的遗传变异度; Nei’s 遗传相似性和主成分分析均显示, 中国福建群体与美国群体间的遗传相似性最高, 而福建群体与黑龙江群体间遗传相似性最低; 聚类分析显示, 供试菌株在88%的相似性水平上可区分为7个聚类组, 且美国群体分布于更多的聚类组中; Shannon-Wiener多样性指数也表明美国群体的遗传多样性最为丰富。综合分析表明, 本研究的结果不支持关于美国的大豆疫霉可能来源于中国的推测。  相似文献   

10.
The steady rise in the prevalence of obesity has had a negative impact for people living with obesity. This includes health care and social disparities that lead to diminished quality of life and social prosperity. Even though discrimination based on weight has a negative impact on people’s health and wellness, there is only one state in the United States, Michigan, that has an antiweight discrimination law. Massachusetts and some cities in the United States have been working to ensure that weight is added as a civil protection over the years. This perspective describes the importance of a weight discrimination law in the United States as well as summarizes the currently existing protections in the country.  相似文献   

11.
Dogs are reservoir hosts for Trypanosoma cruzi , the causative agent of American trypanosomiasis. A rapid immunochromatographic dipstick test (ICT) is available commercially for canine serological testing. The ICT was developed with the use of sera from South American dogs, but it is not routinely used in the United States. We evaluated the utility of the ICT in detecting anti-T. cruzi antibodies in dogs from the United States. Dogs (N = 64) were experimentally infected with United States' isolates of T. cruzi from an opossum (Didelphis virginiana), an armadillo (Dasypus novemcinctus), and a domestic dog (Canis familiaris), and were tested after experimental infection. Sera from uninfected United States dogs (n = 79; hemaculture negative) were used as negative controls. In a blind study, sera were tested by the ICT and compared to the indirect immunofluorescent antibody test with the use of Brazil-strain epimastigotes as antigen. The sensitivity of the ICT was 91% and the specificity was 98% in dogs experimentally infected with United States isolates. Our study indicates that the ICT could be a useful screening tool for serological surveillance of canine T. cruzi exposure in the United States.  相似文献   

12.
Significant interest exists in establishing synergistic research in bioinformatics, systems biology and intelligent computing. Supported by the United States National Science Foundation (NSF), International Society of Intelligent Biological Medicine (http://www.ISIBM.org), International Journal of Computational Biology and Drug Design (IJCBDD) and International Journal of Functional Informatics and Personalized Medicine, the ISIBM International Joint Conferences on Bioinformatics, Systems Biology and Intelligent Computing (ISIBM IJCBS 2009) attracted more than 300 papers and 400 researchers and medical doctors world-wide. It was the only inter/multidisciplinary conference aimed to promote synergistic research and education in bioinformatics, systems biology and intelligent computing. The conference committee was very grateful for the valuable advice and suggestions from honorary chairs, steering committee members and scientific leaders including Dr. Michael S. Waterman (USC, Member of United States National Academy of Sciences), Dr. Chih-Ming Ho (UCLA, Member of United States National Academy of Engineering and Academician of Academia Sinica), Dr. Wing H. Wong (Stanford, Member of United States National Academy of Sciences), Dr. Ruzena Bajcsy (UC Berkeley, Member of United States National Academy of Engineering and Member of United States Institute of Medicine of the National Academies), Dr. Mary Qu Yang (United States National Institutes of Health and Oak Ridge, DOE), Dr. Andrzej Niemierko (Harvard), Dr. A. Keith Dunker (Indiana), Dr. Brian D. Athey (Michigan), Dr. Weida Tong (FDA, United States Department of Health and Human Services), Dr. Cathy H. Wu (Georgetown), Dr. Dong Xu (Missouri), Drs. Arif Ghafoor and Okan K Ersoy (Purdue), Dr. Mark Borodovsky (Georgia Tech, President of ISIBM), Dr. Hamid R. Arabnia (UGA, Vice-President of ISIBM), and other scientific leaders. The committee presented the 2009 ISIBM Outstanding Achievement Awards to Dr. Joydeep Ghosh (UT Austin), Dr. Aidong Zhang (Buffalo) and Dr. Zhi-Hua Zhou (Nanjing) for their significant contributions to the field of intelligent biological medicine.  相似文献   

13.
The subfield of anthropology and education has developed differently in Canada from the path it followed in the United States, even though the discipline of anthropology shared individuals and research topics across the border. Anthropology and education in Canada is distinctly Canadian and is a peripheral version of the central subdiscipline found in the United States.  相似文献   

14.
The sugarcane borer moth, Diatraea saccharalis, is widespread throughout the Western Hemisphere, and is considered an introduced species in the southern United States. Although this moth has a wide distribution and is a pest of many crop plants including sugarcane, corn, sorghum and rice, it is considered one species. The objective was to investigate whether more than one introduction of D. saccharalis had occurred in the southern United States and whether any cryptic species were present. We field collected D. saccharalis in Texas, Louisiana and Florida in the southern United States. Two molecular markers, AFLPs and mitochondrial COI, were used to examine genetic variation among these regional populations and to compare the sequences with those available in GenBank and BOLD. We found geographic population structure in the southern United States which suggests two introductions and the presence of a previously unknown cryptic species. Management of D. saccharalis would likely benefit from further investigation of population genetics throughout the range of this species.  相似文献   

15.
Eight isolates of Fusarium of the Sporotrichiella section were critically studied as to their taxonomic position. Most of these isolates had been used for comprehensive toxicological work on mycotoxin effects on animals, chiefly in the United States and Japan. Isolates NRRL 3299 and NRRL 3287, supplied from the United States, were determined to be Fusarium poae. Isolates NRRL 3249, NRRL 5908, 2061-C, and YN-13 from the United States and isolate T-2 from South Africa belonged to Fusarium sporotrichioides. Isolate NRRL 3509 belonged to F. sporotrichioides var. tricinctum. The relevance of recent toxicological work with these isolates on animals to earlier work on alimentary toxic aleukia is discussed in light of the above identifications.  相似文献   

16.
In today's complex global supply chains, time and data intensive analyses are required to understand global flows of mineral commodities from mine to consumer, particularly for mineral commodities in products (electronics, automobiles, etc.) that contain multiple parts with many mineral commodities. National and regional analyses require additional time and data to incorporate international trade flows. However, data limitations and time constraints often prohibit global and national material flow analyses for minor metals. Here we present a methodological approach to circumvent these constraints by utilizing readily available industry-level global data from the United Nations Statistics Division and national industrial data to estimate total requirements for a mineral commodity. We apply this approach to lithium and cobalt use in the United States for the year 2018 and distinguish between apparent raw material consumption versus inferred embedded consumption of lithium and cobalt materials in all forms. The results show that more than half of the United States’ total requirements for both lithium and cobalt is in parts and products that were manufactured outside the United States. In large part, this is due to limited US manufacturing capability for lithium-ion battery materials and cells and the United States’ high import reliance for electronics that use those batteries.  相似文献   

17.
随着全球人口增长,世界范围内野地-城市交界域(WUI)正在加速扩张。美国的WUI面积大、分布广、聚集人口多,由于交界域直接与森林植被相贯通,极易受到林火影响,区域范围内人类生命财产安全面临巨大威胁。经过长期的火灾管理实践,美国形成了一套较为完善的WUI林火预防、扑救管理体系。本文从美国WUI的形成方式、火灾发生情况、预防扑救措施等几方面系统总结了美国WUI火灾的管理体系。此外,本文分析了我国WUI火灾管理的现状及存在问题,并基于美国经验提出了完善我国WUI火灾管理的六点建议:(1)制定交界域消防管理计划;(2)合理利用计划火烧;(3)研发火灾预警系统;(4)增强社区防火能力;(5)提高消防员灭火水平;(6)完善火灾扑救策略。  相似文献   

18.
Shigella sonnei has become the most frequently reported cause of shigellosis in the United States. Since Shigella subgroup D has no other serotypes, colicin production has been used as a basis for differentiating and identifying epidemiologically related strains. The results of colicin typing 115 cultures of S. sonnei from eight outbreaks of shigellosis occurring in widely separated regions of the United States support the usefulness of this technique. In each outbreak, the cultures were either of the same colicin type or were uniformly untypable. Unrelated cases yielded a variety of types. Definitions of the relative frequencies and geographic distributions of the various strains of S. sonnei in the United States await an accumulation of experience with the method.  相似文献   

19.
This essay examines the spaces across societies in which persons with severe mental illness lose meaningful social roles and are reduced to "bare life." Comparing ethnographic and interview data from the United States and India, we suggest that these processes of exclusion take place differently: on the street in the United States, and in the family household in India. We argue that cultural, historical, and economic factors determine which spaces become zones of social abandonment across societies. We compare strategies for managing and treating persons with psychosis across the United States and India, and demonstrate that the relative efficiency of state surveillance of populations and availability of public social and psychiatric services, the relative importance of family honor, the extent to which a culture of psychopharmaceutical use has penetrated social life, and other historical features, contribute to circumstances in which disordered Indian persons are more likely to be forcefully "hidden" in domestic space, whereas mentally ill persons in the United States are more likely to be expelled to the street. However, in all locations, social marginalization takes place by stripping away the subject's efficacy in social communication. That is, the socially "dead" lose communicative efficacy, a predicament, following Agamben, we describe as "bare voice."  相似文献   

20.
Background. Strains of Helicobacter pylori that express the CagA protein are associated with a threefold increased gastric cancer risk as compared to H. pylori strains that do not express CagA. Screening and treatment only for CagA antibodies should target those individuals at highest gastric cancer risk while reducing the number of patients requiring antibiotics. We compared the costs and benefits of screening asymptomatic 50-year-old individuals for CagA, screening for all H. pylori strains, and no screening, both in the United States and abroad.
Materials and Methods. We employed Markov cost-effectiveness analysis using data from randomized, case-control, and cohort studies.
Results. In the United States, CagA screening would result in 1.5 million fewer antibiotic treatments but would prevent 1,400 fewer gastric cancers than would screening for all H. pylori. The incremental cost-effectiveness of CagA screening is $23,900 per life-year gained; for H. pylori screening, it is $25,100. Screening in countries with epidemiological characteristics similar to those of Colombia, Finland, and Japan costs less than $5,000 per life-year gained, and the difference between CagA and H. pylori screening is smaller than that in the United States.
Conclusions. Screening only for CagA-positive H. pylori is not substantially better than is screening for all H. pylori , either in the United States nor abroad. Screening is substantially more cost-effective outside the United States. Whether population screening is justified, however, is uncertain pending conclusive data regarding the reduction in gastric cancer risk from antibiotics.  相似文献   

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