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1.
This study tests whether seasonal differences in the United States and European sunshine is associated with human birth patterns. Birth data are adjusted for 31-day months, leap years, and an annual percentage. Clear observations and birth indices are correlated for European and U.S. cities. With 2-month exposure to clearness, r-values are Chicago (0.63), Bismarck (0.81), Dallas (0.86), Thessaloniki (0.66), and Copenhagen (0.54) and, with 3-month exposure, Amsterdam (0.69). Peak clearness occurs during the autumn for the United States and spring/summer for Europe. Differences in clearness may explain birth pattern differences and reduced U.S. births in the 1930s. Although the effect of vitamin D is plausible, further research is required.  相似文献   

2.
《Life sciences》1994,56(3):PL51-PL62
Data from the World Health Organization, U.S. Vital Statistics, the Historical Abstracts of the United States and the census of the United States were used to compare current world and states data on cancer death rate and age with historical data that shows the changing percentage of elderly. Current annual death rates from malignant neoplastic disease among the 73 countries for which data exist are highly correlated with the percent of the population ≥ 60 yrs of age and a virtually identical relation exists presently among the 50 states of the U.S. The current world and states data provide a remarkably accurate snapshot of U.S. cancer death rates over the past century during which time the U.S. elderly population increased substantially. Data on U.S. lung cancer death rates since 1940 were similarly examined and these historical numbers also show good agreement with current values among countries that today span the same proportion of elderly that the U.S. had over this period. The agreement of current and historical CA death rate and age contrasts sharply with the picture that emerges when cardiovascular death rates and death rate from all causes are examined. The geographic and time invariance seen in the cancer data seems incosistent with identical exposure to carcinogens and suggests that biological aging is an important intrinsic factor in cancer.  相似文献   

3.
This study tests whether seasonal differences in the United States and European sunshine is associated with human birth patterns. Birth data are adjusted for 31-day months, leap years, and an annual percentage. Clear observations and birth indices are correlated for European and U.S. cities. With 2-month exposure to clearness, r-values are Chicago (0.63), Bismarck (0.81), Dallas (0.86), Thessaloniki (0.66), and Copenhagen (0.54) and, with 3-month exposure, Amsterdam (0.69). Peak clearness occurs during the autumn for the United States and spring/summer for Europe. Differences in clearness may explain birth pattern differences and reduced U.S. births in the 1930s. Although the effect of vitamin D is plausible, further research is required.  相似文献   

4.
This study assessed potential human health risks posed by tributyltin in seafood purchased from U.S. seafood markets. In 1989 and 1990, samples of fish, bivalve molluscs and crustacea were purchased at local markets along the Atlantic, Gulf and Pacific coasts of the United States and along the Great Lakes (Lake Michigan). Samples were then analyzed for tributyltin, and the concentrations observed used to evaluate potential human health risks from consumption of market-bought seafood on the basis of available mammalian toxicology data. The assessment indicated health effects were unlikely from exposure to tributyltin in market-bought seafood during 1989 to 1990, shortly after peak tributyltin usage in antifoulant bottom paints on vessels in the United States.  相似文献   

5.
Putila JJ  Guo NL 《PloS one》2011,6(10):e25886

Background

Although strong exposure to arsenic has been shown to be carcinogenic, its contribution to lung cancer incidence in the United States is not well characterized. We sought to determine if the low-level exposures to arsenic seen in the U.S. are associated with lung cancer incidence after controlling for possible confounders, and to assess the interaction with smoking behavior.

Methodology

Measurements of arsenic stream sediment and soil concentration obtained from the USGS National Geochemical Survey were combined, respectively, with 2008 BRFSS estimates on smoking prevalence and 2000 U.S. Census county level income to determine the effects of these factors on lung cancer incidence, as estimated from respective state-wide cancer registries and the SEER database. Poisson regression was used to determine the association between each variable and age-adjusted county-level lung cancer incidence. ANOVA was used to assess interaction effects between covariates.

Principal Findings

Sediment levels of arsenic were significantly associated with an increase in incident cases of lung cancer (P<0.0001). These effects persisted after controlling for smoking and income (P<0.0001). Across the U.S., exposure to arsenic may contribute to up to 5,297 lung cancer cases per year. There was also a significant interaction between arsenic exposure levels and smoking prevalence (P<0.05).

Conclusions/Significance

Arsenic was significantly associated with lung cancer incidence rates in the U.S. after controlling for smoking and income, indicating that low-level exposure to arsenic is responsible for excess cancer cases in many parts of the U.S. Elevated county smoking prevalence strengthened the association between arsenic exposure and lung cancer incidence rate, an effect previously unseen on a population level.  相似文献   

6.
Dioxin concentrations remain elevated in the environment and in humans residing near former US Air Force bases in South Vietnam. Our previous epidemiological studies showed adverse effects of dioxin exposure on neurodevelopment for the first 3 years of life. Subsequently, we extended the follow-up period and investigated the influence of perinatal dioxin exposure on neurodevelopment, including motor coordination and higher cognitive ability, in preschool children. Presently, we investigated 176 children in a hot spot of dioxin contamination who were followed up from birth until 5 years old. Perinatal dioxin exposure levels were estimated by measuring dioxin levels in maternal breast milk. Dioxin toxicity was evaluated using two indices; toxic equivalent (TEQ)-polychlorinated dibenzo-p-dioxins/furans (PCDDs/Fs) and concentration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Coordinated movements, including manual dexterity, aiming and catching, and balance, were assessed using the Movement Assessment Battery for Children, Second Edition (Movement ABC-2). Cognitive ability was assessed using the nonverbal index (NVI) of the Kaufman Assessment Battery for Children, Second Edition (KABC-II). In boys, total test and balance scores of Movement ABC-2 were significantly lower in the high TEQ- PCDDs/Fs group compared with the moderate and low exposure groups. NVI scores and the pattern reasoning subscale of the KABC-II indicating planning ability were also significantly lower in the high TCDD exposure group compared with the low exposure group of boys. However, in girls, no significant differences in Movement ABC-2 and KABC-II scores were found among the different TEQ-PCDDs/Fs and TCDD exposure groups. Furthermore, in high risk cases, five boys and one girl highly exposed to TEQ-PCDDs/Fs and TCDD had double the risk for difficulties in both neurodevelopmental skills. These results suggest differential impacts of TEQ-PCDDs/Fs and TCDD exposure on motor coordination and higher cognitive ability, respectively. Moreover, high TEQ-PCDDs/Fs exposure combined with high TCDD exposure may increase autistic traits combined with developmental coordination disorder.  相似文献   

7.
Native to Asia, the emerald ash borer (Agrilus planipennis Fairmaire) has caused extensive mortality of ash tree species (Fraxinus spp.) in the eastern United States. As of 2013, the pest was documented in 18 % of counties within the natural range of ash in the eastern United States. Regional forest inventory data from the U.S. Forest Service Forest Inventory and Analysis program were used to quantify trends in ash mortality rate and volume per hectare relative to the year of initial emerald ash borer detection. Results indicate that the annual ash mortality rate increases by as much as 2.7 % per year after initial detection of the pest in a county. Corresponding decreases in ash volume (as much as 1.8 m3 per hectare per year) continue for several more years until most live ash is killed. These results, while not necessarily representative of the effects on ash in urban ecosystems, document the severe impact this invading herbivore is having on forests as it expands its range in North America.  相似文献   

8.
A growing body of literature has documented a link between neighborhood context and health outcomes. However, little is known about the relationship between neighborhood context and body mass index (BMI) or whether the association between neighborhood context and BMI differs by ethnicity. This paper investigates several neighborhood characteristics as potential explanatory factors for the variation of BMI across the United States; further, this paper explores to what extent segregation and the concentration of disadvantage across neighborhoods help explain ethnic disparities in BMI. Using data geo-coded at the census tract-level and linked with individual-level data from the Third National Health and Examination Survey in the United States (U.S.), we find significant variation in BMI across U.S. neighborhoods. In addition, neighborhood characteristics have a significant association with body mass and partially explain ethnic disparities in BMI, net of individual-level adjustments. These data also reveal evidence that ethnic enclaves are not in fact advantageous for the body mass index of Hispanics-a relationship counter to what has been documented for other health outcomes.  相似文献   

9.
Greenland S 《Biometrics》2001,57(1):182-188
Standard presentations of epidemiological results focus on incidence-ratio estimates derived from regression models fit to specialized study data. These data are often highly nonrepresentative of populations for which public-health impacts must be evaluated. Basic methods are provided for interval estimation of attributable fractions from model-based incidence-ratio estimates combined with independent survey estimates of the exposure distribution in the target population of interest. These methods are illustrated in estimation of the potential impact of magnetic-field exposures on childhood leukemia in the United States, based on pooled data from 11 case-control studies and a U.S. sample survey of magnetic-field exposures.  相似文献   

10.
BACKGROUND: Literature on the risk of birth defects among foreign‐ versus U.S.–born Hispanics is limited or inconsistent. We examined the association between country of birth, immigration patterns, and birth defects among Hispanic mothers. METHODS: We used data from the National Birth Defects Prevention Study and calculated odds ratios (ORs) and 95% confidence intervals and assessed the relationship between mothers' country of birth, years lived in the United States, and birth defects among 575 foreign‐born compared to 539 U.S.–born Hispanic mothers. RESULTS: Hispanic mothers born in Mexico/Central America were more likely to deliver babies with spina bifida (OR = 1.53) than their U.S.–born counterparts. Also, mothers born in Mexico/Central America or who were recent United States immigrants (≤5 years) were less likely to deliver babies with all atrial septal defects combined, all septal defects combined, or atrial septal defect, secundum type. However, Hispanic foreign‐born mothers who lived in the United States for >5 years were more likely to deliver babies with all neural tube defects combined (OR = 1.42), spina bifida (OR = 1.89), and longitudinal limb defects (OR = 2.34). Foreign‐born mothers, regardless of their number of years lived in the United States, were more likely to deliver babies with anotia or microtia. CONCLUSIONS: Depending on the type of birth defect, foreign‐born Hispanic mothers might be at higher or lower risk of delivering babies with the defects. The differences might reflect variations in predisposition, cultural norms, behavioral characteristics, and/or ascertainment of the birth defects. Birth Defects Research (Part A), 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

11.
Abstract

It has been argued that the issuance of the U.S. Exclusive Economic Zone (EEZ) Proclamation could lead to difficulties in the management of our coastal resources. This paper will examine the consequences of a U.S. EEZ for fisheries and marine transportation. For each sector consideration will be given to the inconsistencies which exist between the United Nations Convention on the Law of the Sea, the U.S. Proclamation, and existing U.S. legislation. The problems and opportunities presented by these inconsistencies are discussed. The authors conclude that, while some modifications of U.S. policy may be required, wide‐ranging changes are neither likely nor needed.  相似文献   

12.
The Black–Foot Disease (BFD) endemic area of SW Taiwan has historically been the principal data source for assessing cancer risks from arsenic in drinking water in the United States, most recently in a 42–village ecological study. The data showed a discontinuity for bladder cancer risk at about 400 μg/L. A proposed explanation was that the arsenic–dependent bladder cancer risk was found only for those villages that were dependent on water from the artesian well aquifer (As > 350 μg/L and co–contamination with humic acids) and not for those villages receiving water from the shallow aquifer (As < 350 μg/L without humic acids). The humic acids were present from the algae that grew in the uncovered tanks holding the artesian water. The risk factors (slopes) developed from these subpopulations of the SW Taiwan study were applied to the data from an ecological study of median groundwater arsenic concentration and bladder cancer mortality in 133 U.S. counties dependent on groundwater to determine the slope most predictive of U.S. experience for bladder cancer mortality and arsenic ingestion (Lamm et al. 2004 Lamm, S H, Engel, AKruse, M B. 2004. Arsenic in drinking water and bladder cancer mortality in the United States: An analysis based on 133 U.S. counties and 30 years of observation.. J Occup Environ Med, 46(3): 298306. [PUBMED][INFOTRIEVE][CSA][Crossref], [PubMed], [Web of Science ®] [Google Scholar]).The U.S. data excluded the SW Taiwan slope estimate derived from the artesian well–dependent subpopulation but were consistent with the slope estimate derived from the subpopulation using shallow aquifer water. Both the SW Taiwan data in the absence of high arsenic levels (< 350 μg/L) and humic acids and the U.S. 133–county data with As < 60 μg/L are consistent with no increased bladder cancer mortality risk from drinking water arsenic concentrations in the exposure range of observation. These analytic results are consistent with both co–carcinogenesis and high–exposure (hundreds of μ g/L As) dependence models of toxicological mode–of–action. These dose–response relationships should influence prioritization in the remediation of arsenic–contaminated drinking water supplies.  相似文献   

13.
An extensive survey of pollen distribution in surficial sediments from the slope and rise between 29° and 72°N, shows patterns which reflect the distribution of vegetation in eastern North America and the effects of aeolian, fluvial, and marine sedimentation. The results of the analysis of 94 core tops show that pollen concentration ranges from 23,000 to 10 grains per gram, and decreases offshore with distance from vegetation sources and northward in relation to lower vegetation density. Maximum concentration occurs in organic-rich, fine-grained lutum deposited off rivers draining the southeastern United States. Low pollen concentrations are associated with high-energy environments, such as the Western Boundary Undercurrent and the Labrador Current. Percentages of dominant pollen types generally correspond with onshore distribution of pollen and vegetation. Oak and other deciduous pollen types are the most abundant in marine sediments off the deciduous forests of eastern United States. Hemlock pollen is essentially restricted to sediments off the hemlock-oak forests of northeastern U.S. and southeastern Canada, and spruce pollen is most abundant adjacent boreal forests and forest-tundra formations. The relative increase in pine pollen seaward reflects the selective effects of marine transport. Synthesis of pollen data by Q-mode factor analysis shows that major vegetation formations of eastern North America produce distinctive, regional marine pollen assemblages.  相似文献   

14.
Bald eagles (Haliaeetus leucocephalus) are currently protected in the United States under the Bald and Golden Eagle Protection Act of 1940 and Migratory Bird Treaty Act of 1918. Given these protections and the increasing development of wind energy throughout the United States, it is important for regulators and the wind industry to understand the risk of bald eagle collisions with wind turbines. Prior probability distributions for eagle exposure rates and collision rates have been developed for golden eagles (Aquila chrysaetos) by the United States Fish and Wildlife Service (USFWS). Given similar information has not been available for bald eagles, the current recommendation by the USFWS is to use the prior probability distributions developed using data collected on golden eagles to predict take for bald eagles. But some evidence suggests that bald and golden eagles may be at different risk for collision with wind turbines and the prior probability distributions developed for golden eagles may not be appropriate for bald eagles. We developed prior probability distributions using data collected at MidAmerican Energy Company's operating wind energy facilities in Iowa, USA, from December 2014 to March 2017 for bald eagle exposure rates and collision rates. The prior probability distribution for collision rate developed for bald eagles has a lower mean collision rate and less variability relative to that developed for golden eagles. We determined that the prior probability distributions specific to bald eagles from these operating facilities are a better starting point for predicting take for bald eagles at operating wind energy facilities in an agricultural landscape than those developed for golden eagles. © 2021 The Wildlife Society.  相似文献   

15.
RAYMOND J. O'CONNOR 《Ibis》1991,133(S1):36-48
Long-term population studies of birds in the United States have been less species-oriented and more concept-oriented than in Britain. The demographics of North American species do not differ grossly from those of species elsewhere in the world, but polygamy has been relatively more frequently studied in U.S. species than elsewhere. Subjects that have been particularly explored in long-term studies in the United States include the determinants of cooperative breeding in birds, the effects of the spatial scale on what is learned, and correlates of regional and national declines in bird populations. Other areas of developing interest include the potential uses of monitoring data, the relative value of longitudinal and cross-sectional studies in analysing slow processes, and the significance of episodic events in shaping population patterns.  相似文献   

16.
The environmental impacts of data centers that provide information and communication technologies (ICTs) services are strongly related to electricity generation. With the increasing use of ICT, many data centers are expected to be built, causing more absolute impacts on the environment. Given that electricity distribution networks are very complex and dynamic systems, an environmental evaluation of future data centers is uncertain. This study proposes a new approach to investigate the consequences of future data center deployment in Canada and optimize this deployment based on the Energy 2020 technoeconomic model in combination with life cycle assessment methodology. The method determines specific electricity sources that will power the future Canadian data centers and computes related environmental impacts based on several indicators. In case‐study scenarios, the largest deployment of data centers leads to the smallest impact per megawatt of data centers for all of the environmental indicators. It is found that an increase in power demand by data centers would lead to a reduction in electricity exports to the United States, driving the United States to generate more electricity to meet its energy demand. Given that electricity generation in the United States is more polluting than in Canada, the deployment of data centers in Canada is indirectly linked to an increase in overall environmental impacts. However, though an optimal solution should be found to mitigate global greenhouse gas emissions, it is not clear whether the environmental burden related to U.S. electricity generation should be attributed to the Canadian data centers.  相似文献   

17.
This study compares four models for predicting the potential distribution of non-indigenous weed species in the conterminous U.S. The comparison focused on evaluating modeling tools and protocols as currently used for weed risk assessment or for predicting the potential distribution of invasive weeds. We used six weed species (three highly invasive and three less invasive non-indigenous species) that have been established in the U.S. for more than 75 years. The experiment involved providing non-U. S. location data to users familiar with one of the four evaluated techniques, who then developed predictive models that were applied to the United States without knowing the identity of the species or its U.S. distribution. We compared a simple GIS climate matching technique known as Proto3, a simple climate matching tool CLIMEX Match Climates, the correlative model MaxEnt, and a process model known as the Thornley Transport Resistance (TTR) model. Two experienced users ran each modeling tool except TTR, which had one user. Models were trained with global species distribution data excluding any U.S. data, and then were evaluated using the current known U.S. distribution. The influence of weed species identity and modeling tool on prevalence and sensitivity effects was compared using a generalized linear mixed model. Each modeling tool itself had a low statistical significance, while weed species alone accounted for 69.1 and 48.5% of the variance for prevalence and sensitivity, respectively. These results suggest that simple modeling tools might perform as well as complex ones in the case of predicting potential distribution for a weed not yet present in the United States. Considerations of model accuracy should also be balanced with those of reproducibility and ease of use. More important than the choice of modeling tool is the construction of robust protocols and testing both new and experienced users under blind test conditions that approximate operational conditions.  相似文献   

18.
Rift Valley fever virus (RVFV) is a mosquito-borne virus in the family Bunyaviridiae that has spread throughout continental Africa to Madagascar and the Arabian Peninsula. The establishment of RVFV in North America would have serious consequences for human and animal health in addition to a significant economic impact on the livestock industry. Published and unpublished data on RVFV vector competence, vertebrate host competence, and mosquito feeding patterns from the United States were combined to quantitatively implicate mosquito vectors and vertebrate hosts that may be important to RVFV transmission in the United States. A viremia-vector competence relationship based on published mosquito transmission studies was used to calculate a vertebrate host competence index which was then combined with mosquito blood feeding patterns to approximate the vector and vertebrate amplification fraction, defined as the relative contribution of the mosquito or vertebrate host to pathogen transmission. Results implicate several Aedes spp. mosquitoes and vertebrates in the order Artiodactyla as important hosts for RVFV transmission in the U.S. Moreover, this study identifies critical gaps in knowledge which would be necessary to complete a comprehensive analysis identifying the different contributions of mosquitoes and vertebrates to potential RVFV transmission in the U.S. Future research should focus on (1) the dose-dependent relationship between viremic exposure and the subsequent infectiousness of key mosquito species, (2) evaluation of vertebrate host competence for RVFV among North American mammal species, with particular emphasis on the order Artiodactyla, and (3) identification of areas with a high risk for RVFV introduction so data on local vector and host populations can help generate geographically appropriate amplification fraction estimates.  相似文献   

19.
以美国农业部国家农业统计局公布的相关数据为基础,首先简要介绍美国主要农作物种植变化情况,然后对2000~2011年美国主要转基因作物种植面积、性状等进行分析,得出了美国主要转基因作物种植的发展趋势。最后简要介绍我国相应转基因作物的发展情况,并据此提出我国发展转基因作物的几点建议。  相似文献   

20.
Networks are rarely completely observed and prediction of unobserved edges is an important problem, especially in disease spread modeling where networks are used to represent the pattern of contacts. We focus on a partially observed cattle movement network in the U.S. and present a method for scaling up to a full network based on Bayesian inference, with the aim of informing epidemic disease spread models in the United States. The observed network is a 10% state stratified sample of Interstate Certificates of Veterinary Inspection that are required for interstate movement; describing approximately 20,000 movements from 47 of the contiguous states, with origins and destinations aggregated at the county level. We address how to scale up the 10% sample and predict unobserved intrastate movements based on observed movement distances. Edge prediction based on a distance kernel is not straightforward because the probability of movement does not always decline monotonically with distance due to underlying industry infrastructure. Hence, we propose a spatially explicit model where the probability of movement depends on distance, number of premises per county and historical imports of animals. Our model performs well in recapturing overall metrics of the observed network at the node level (U.S. counties), including degree centrality and betweenness; and performs better compared to randomized networks. Kernel generated movement networks also recapture observed global network metrics, including network size, transitivity, reciprocity, and assortativity better than randomized networks. In addition, predicted movements are similar to observed when aggregated at the state level (a broader geographic level relevant for policy) and are concentrated around states where key infrastructures, such as feedlots, are common. We conclude that the method generally performs well in predicting both coarse geographical patterns and network structure and is a promising method to generate full networks that incorporate the uncertainty of sampled and unobserved contacts.  相似文献   

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