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1.
The latest data (NHANES III) from the National Center for Health Statistics (NCHS) show that the black population has the highest proportion of overweight among all adult populations in the United States. The present study compared the body mass index (BMI) and body fat percent from dual-photon absorptiometry in 1,324 healthy adults aged 18 to 107 years recruited from four ethnic groups in the New York City area; 523 whites, 280 blacks, 267 Asians and 254 Puerto Ricans. Puerto Ricans had the largest BMI and the largest percent of subjects with body weight more than 120% of their ideal weight, and the largest fat percent of the four ethnic groups: 76% of Puerto Rican males had fat percent above the median value for white males (fat percent = 19.6%) and 95% of Puerto Rican females had fat percent above the median for white females (fat percent = 30.8%). Asians had the smallest BMI, but 63% of them had fat percent above the median values for whites in each gender. Puerto Ricans also had the largest waist-to-hip ratios among the four ethnic groups. In blacks, the percent of subjects with fat percent larger than the median for whites was slightly smaller than that for Puerto Ricans, 64% and 82% of males and females respectively. These results differ from the latest NCHS data and show that Puerto Ricans in this sample are heavier and fatter than blacks.  相似文献   

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One of the most significant challenges in developing a predictive understanding of the long-term effects of hurricanes on tropical forests is the development of quantitative models of the relationships between variation in storm intensity and the resulting severity of tree damage and mortality. There have been many comparative studies of interspecific variation in resistance of trees to wind damage based on aggregate responses to individual storms. We use a new approach, based on ordinal logistic regression, to fit quantitative models of the susceptibility of a tree species to different levels of damage across an explicit range of hurricane intensity. Our approach simultaneously estimates both the local intensity of the storm within a plot and the susceptibility to storm damage of different tree species within plots. Using the spatial variation of storm intensity embedded in two hurricanes (Hugo in 1989 and Georges in 1998) that struck the 16 ha Luquillo Forest Dynamics Plot in eastern Puerto Rico, we show that variation in susceptibility to storm damage is an important aspect of life history differentiation. Pioneers such as Cecropia schreberiana are highly susceptible to stem damage, while the late successional species Dacryodes excelsa suffered very little stem damage but significant crown damage. There was a surprisingly weak relationship between tree diameter and the susceptibility to damage for most of the 12 species examined. This may be due to the effects of repeated storms and trade winds on the architecture of trees and forest stands in this Puerto Rican subtropical wet forest.
Abstract in Spanish is available at http://www.blackwell-synergy.com/loi/btp .  相似文献   

4.
Bird Perches Increase Forest Seeds on Puerto Rican Landslides   总被引:10,自引:0,他引:10  
Abstract Landslides result in the loss of vertical vegetative structure, soil nutrients, and the soil seed bank. These losses impede timely recovery of tropical forest communities. In this study we added bird perches to six Puerto Rican landslides with three types of surfaces (bare, climbing fern, grass) in an effort to facilitate inputs of forest seeds through bird dispersal and to accelerate plant succession. Numbers of bird‐dispersed forest seeds were significantly higher in plots beneath introduced perches than in control plots. Perches did not increase forest seedling densities compared with control plots. Seven different species of birds were observed on introduced perches. Because 99% of the seed inputs to controls and perch plots in the six landslides were wind‐dispersed seeds (mostly graminoids), perches can improve landslide restoration if woody plants establish and shade out the dominant graminoid and climbing fern ground cover. Although increasing seed inputs from forest species is a critical step in accelerating revegetation of landslides, we suggest that supplemental restoration techniques be applied in addition to bird perches to promote forest recovery.  相似文献   

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Quaternary climatic oscillations caused changes in sea level that altered the size, number and degree of isolation of islands, particularly in land‐bridge archipelagoes. Elucidating the demographic effects of these oscillations increases our understanding of the role of climate change in shaping evolutionary processes in archipelagoes. The Puerto Rican Bank (PRB) (Puerto Rico and the Eastern Islands, which comprise Vieques, Culebra, the Virgin Islands and associated islets) in the eastern Caribbean Sea periodically coalesced during glaciations and fragmented during interglacial periods of the quaternary. To explore population‐level consequences of sea level changes, we studied the phylogeography of the frog Eleutherodactylus antillensis across the archipelago. We tested hypotheses encompassing vicariance and dispersal narratives by sequencing mtDNA (c. 552 bp) of 285 individuals from 58 localities, and four nuDNA introns (totalling c. 1633 bp) from 173 of these individuals. We found low support for a hypothesis of divergence of the Eastern Islands populations prior to the start of the penultimate interglacial c. 250 kya, and higher support for a hypothesis of colonization of the Eastern Islands from sources in eastern Puerto Rico during the penultimate and last glacial period, when a land bridge united the PRB. The Río Grande de Loíza Basin in eastern Puerto Rico delineates a phylogeographic break. Haplotypes shared between the PRB and St. Croix (an island c. 105 km south‐east of this archipelago) likely represent human‐mediated introductions. Our findings illustrate how varying degrees of connectivity and isolation influence the evolution of tropical island organisms.  相似文献   

6.
纽约弹性城市建设经验及其对上海的启示   总被引:1,自引:0,他引:1  
面临气候变化带来的全球性环境、社会、经济灾难,许多国家、地区都制定了应对方案并采取行动。与上海市有着同样区位优势的纽约市,作为全球城市在有关气候变化的城市治理方面一直处于国际领先地位,引领全球城市开展弹性城市建设。在总结纽约弹性城市建设发展历程基础上,分析纽约市弹性城市建设所面临的挑战和机遇,未来100年总目标及其包含4个分目标,以及实现这4个分目标的具体措施。最后,对比纽约市与上海市的相似性,从弹性城市项目建设、投融资、区域合作、政府治理这4个方面为上海市弹性城市建设带来启示。  相似文献   

7.
Hispanic and African American populations exhibit an increased risk of obesity compared with populations of European origin, a feature that may be related to inherited risk alleles from Native American and West African parental populations. However, a relationship between West African ancestry and obesity-related traits, such as body mass index (BMI), fat mass (FM), and fat-free mass (FFM), and with bone mineral density (BMD) in African American women has only recently been reported. In order to evaluate further the influence of ancestry on body composition phenotypes, we studied a Hispanic population with substantial European, West African, and Native American admixture. We ascertained a sample of Puerto Rican women living in New York (n=64), for whom we measured BMI and body composition variables, such as FM, FFM, percent body fat, and BMD. Additionally, skin pigmentation was measured as the melanin index by reflectance spectroscopy. We genotyped 35 autosomal ancestry informative markers and estimated population and individual ancestral proportions in terms of European, West African, and Native American contributions to this population. The ancestry proportions corresponding to the three parental populations are: 53.3±2.8% European, 29.1±2.3% West African, and 17.6±2.4% Native American. We detected significant genetic structure in this population with a number of different tests. A highly significant correlation was found between skin pigmentation and individual ancestry (R2=0.597, P<0.001) that was not attributable to differences in socioeconomic status. A significant association was also found between BMD and European admixture (R2=0.065, P=0.042), but no such correlation was evident with BMI or the remaining body composition measurements. We discuss the implications of our findings for the potential use of this Hispanic population for admixture mapping.  相似文献   

8.
This paper is about naming illnesses—about who determines what categories are used and the implications of these determinations. The central concerns of medical/psychiatric anthropology have been to understand popular categories of and systems for classification of illness, to examine the relationship of illness categories to cultural understandings of the body, and to interpret the role of categories of illness in mediating between the personal and social spheres. At the same time, the paper also discusses the interplay of popular categories and psychiatric diagnoses. This paper examines the multiple experiences of nervios among Puerto Ricans in Puerto Rico and New York City. Our contention is that nervios is more than a diffuse idiom of distress, and that there are different categories and experiences of nervios which provide insights into how distress is experienced and expressed by Puerto Ricans and point to different social sources of suffering. The data in this paper come from the responses to a series of open-ended questions which tapped into people's general conceptions of nervios and ataques de nervios. These questions were incorporated into follow-up interviews to an epidemiological study of the mental health of adults in Puerto Rico. The results suggest ways to incorporate these different categories of nervios into future research and clinical work with different Latino groups in the United States and in their home countries.  相似文献   

9.
We isolate six highly polymorphic microsatellite loci for the Puerto Rican crested anole (Anolis cristatellus) from a genomic library enriched for CA repeats. The number of alleles per locus ranged from 14 to 19, with levels of observed heterozygosity ranging from 0.60 to 0.73. Most of these loci were successfully cross-amplified in other members of the cristatellus species group (A. evermanni, A. gundlachi, A. krugi, A. stratulus), but levels of polymorphism were lower.  相似文献   

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This paper presents evidence for what is believed to be the first reported case of pre-Columbian treponematosis in northeastern North America. The temporal position of the skeletal material, salvaged from a site in New York State, is determined on the basis of archeological evidence.  相似文献   

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Discovery of Tremichnus cysticus Brett on a crinoid pluricolumnal from the Willowvale Shale of western New York extends the range of this ichnogenus into the Lower Silurian. Pits attributable to Tremichnus apparently represent embedment sites of parasites or commensalistic, filter-feeding organisms of unknown affinities. Embedment of T. cysticus may have been accomplished by localized inhibition of stereom growth within the pits aided by secretion of substances that stimulated accretion of stereom by the host pelmatozoan in areas immediately surrounding the pits.  相似文献   

14.
Meiotic chromosomes of 10 West Indian flea beetles with restricted distribution, including eight Puerto Rican endemics, were studied. Two species of the cosmopolitan Longitarsus resemble Old World congenerics in having meioformulae 13 + Xy and 14 + Xy, both with one pair of enlarged autosomes. One unidentified species of Aphthona seems to have achiasmatic meiosis. Among the Puerto Rican endemics, repeated fusions have produced low-numbered karyotypes in Homoschema latitarsum (2 + neoXY, now the lowest meioformula known for the Chrysomelidae) and Heikertingerella krugi (4 + neoXY). Three species of Aedmon have 18 + Xyp as a result of a series of centric fissions from the Polyphagan ancestral condition of nine pairs. Phyllotrupes sp. (a new genus record for Puerto Rico, near P. acutangula ) and Pseudodisonycha portoricensis have 17 + Xy and 16 + Xy, respectively, plus a swarm of supernumerary chromosomes.  相似文献   

15.
Contemporary research indicates that religious institutions can play bonding and bridging roles in the lives of immigrants, strengthening the bonds within immigrant groups while simultaneously connecting immigrants to the wider society. The majority of this research focuses on religious institutions in US cities with long histories of immigration and sizable immigrant populations. This article examines the role of religious institutions in the lives of refugees living in a city with a small, but rapidly growing immigrant population. Evidence from interviews with Catholic and Muslim refugees and participant observation at two houses of worship suggests that the functions of religious institutions differ for refugees from majority and minority religious traditions. Catholic refugees use their church for bonding and bridging purposes, while Muslim refugees use their mosque primarily for bonding purposes.  相似文献   

16.
A new genus of lycopods from the Devonian of New York State   总被引:2,自引:0,他引:2  
Drepanophycus colophyllus Grierson & Banks is transferred to llaskinsia Grierson & Banks on the basis of the morphology of its leaves and its anatomical structure. Slender, dichotomizing axes bear helically arranged leaves that are falcate, petiolate, simple, lanceolate and entire. A solid cylinder of metaxylem is surrounded by ridges of protoxylem. Pitting on tracheid walls is annular, helical, reticulate, scalariform to circular-bordered. This lycopod extends from early Givetian into early Frasnian time in the Catskill strata of eastern New York State. The effect of cleavage of fossiliferous rock on patterns observed on the exposed fossils and the bearing of recent research on the fossil history of lycopods are discussed.  相似文献   

17.
Biomass and cover of Microcoleus lyngbyaceus (Kützing) Crouan were monitored at inshore seagrass habitats in southwest Puerto Rico for 16 months. Substantial localized blooms with maximum cover of 100% and comprising >600 g/m2 were encountered. Abundance of Microcoleus (biomass and percent cover) were not significantly correlated with either water temperature or water column nitrogen (as nitrate and nitrite concentrations). M. lyngbyaceus has locally been implicated as being detrimental to the seagrass Thalassia testudinum König which is supported by circumstantial evidence. Thalassia cover declined in permanent quadrats that were strongly impacted with Microcoleus.  相似文献   

18.
In this article, I examine the identity choices of Ethiopian and Eritrean immigrants of Amhara, Tigrayan and Tigrinya ethnicity within the context of the larger debate on how non-white immigrants are being incorporated into American society. I argue that these immigrants resist racialization even while their actions and attitudes potentially reinforce America's racial divide. They implicitly challenge American racial categories by thinking of themselves as Habasha, which they view as a separate non-black ethno-racial category that emphasizes their Semitic origins. Meanwhile, they often distance themselves from American blacks through pursuing transnational connections, producing Habasha spaces, displaying the attributes of a ‘model minority’ and preserving Habasha beauty through endogamy. By remaining relatively isolated within their ethnic communities in Washington, DC, which is the focus of this study, they may succeed in differentiating themselves from American blacks, but they are not likely to join the American mainstream on a par with whites.  相似文献   

19.
SYNOPSIS. Tintinnida of the New York Bight (a bend in the coastline) were identified during the 1-year period August 1973–August 1974. Recurring genera included Stenosemella and Tintinnopsis; seasonal genera were mainly the hyaline Favella, Metacylis, and Helicostomella; exotic or unusual genera included Parafavella and Ptychocylis. Large size differences in loricae were found seasonally, related apparently, to water temperature.  相似文献   

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