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31.
The objective was to examine BMI of working‐age Canadian adults in relation to occupational prestige, adjusting for other aspects of social class including household income and respondent's education. We analyzed data from 49,252 adults (age 25–64) from Cycle 2.1 of the Canadian Community Health Survey, a cross‐sectional self‐report survey conducted in 2003. Multiple linear regression was used to examine the relation between BMI and occupational prestige, adjusting for other sociodemographic variables. For women, higher ranking occupations showed lower average BMI relative to the lowest ranking occupations, but this effect was largely eliminated when adjusting for education. For men, occupation effects endured in adjusted models and we detected some evidence of a pattern whereby men in occupations characterized by management/supervisory responsibilities were heavier than those in the lowest ranking occupations (i.e., elemental sales and service). Results are interpreted in light of the symbolic value of body size in western culture, which differs for men and women. Men in positions of management/supervision may benefit from the physical dominance conveyed by a larger body size, and thus occupational prestige rankings may help us to understand the gender differences in the patterning of BMI by different indicators of social class.  相似文献   
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We evaluate the conservation status and threats faced by sea turtle nesting populations at Bioko Island, Equatorial Guinea (Central Africa). Beaches were monitored to obtain a detailed sea turtle nest census and, where possible, tagging of adult females was undertaken. Four sea turtle species were found nesting in the area: the green turtle (Chelonia mydas), the leatherback (Dermochelys coriacea), the olive ridley (Lepidochelys olivacea) and the hawksbill (Eretmochelys imbricata); with the former two species nesting in regionally important numbers. Nesting activity was concentrated between November and February, with a peak in December–January. Tagging and recapture of green turtles in two consecutive seasons suggested an estimated 560 (interquartile range: 420–1,681) and 414 (interquartile range: 190–1,255) nesting females in the area, respectively. Estimated numbers of nesting leatherbacks ranged from 123 to 215 and 243 to 293 in the first and second season, respectively. The other two species were less abundant (olive ridley: 19–29 and 28–43; hawksbill: 4–10 and 2 turtles). Data were compared with more recent surveys in the area and contextualised with information on human related threats. Despite the size of nesting stocks, ongoing permitted and illegal take of adult turtles at the nesting site constitutes a serious threat for these breeding aggregations. Additionally, tag returns from throughout the Gulf of Guinea suggest that the level of take in regional fisheries may also be a major threat.  相似文献   
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We analysed the genetic structure of seven nesting sites of the endangered green turtle (Chelonia mydas) in Africa using mitochondrial DNA control region sequences. Tissue samples were collected from 188 nesting females at six sites in West Africa and one in the Indian Ocean. A 488 bp fragment of the control region revealed 14 different haplotypes, 10 of which are previously undescribed. The most common haplotype (CM8) was observed in 157 individuals. All other haplotypes were closely related, except two divergent lineages: CM38, removed by four substitutions, and the three Indian Ocean haplotypes, distinguished by 31 substitutions. Significant differences in haplotype and nucleotide diversity were observed between Atlantic rookeries and among ocean basins. Analysis of molecular variance revealed high levels of differentiation between the Atlantic and the Indian Ocean populations but a much shallower Atlantic substructuring. Green turtle population genetic structure is thought to have been shaped by a dynamic succession of extinction and recolonisation of rookeries, by natal homing and occasional breakdown in nest-site fidelity. Mismatch distributions of pairwise differences between haplotypes at each rookery were found to be consistent with recent population expansion. We argue that demographic histories can be explained by scenarios at several temporal scales, including geological events, sea level fluctuations and more recent patterns of exploitation. We discuss management and conservation implications of our results for these threatened populations, identifying two ESUs (one in the Atlantic and one in the Indian ocean) and three MUs within the Atlantic.  相似文献   
34.
Green turtles (Chelonia mydas) swim from foraging grounds along the Brazilian coast to Ascension Island to nest, over 2200 km distant in the middle of the equatorial Atlantic. To test the hypothesis that turtles use wind-borne cues to locate Ascension Island we found turtles that had just completed nesting and then moved three individuals 50 km northwest (downwind) of the island and three individuals 50 km southeast (upwind). Their subsequent movements were tracked by satellite. Turtles released downwind returned to Ascension Island within 1, 2 and 4 days, respectively. By contrast, those released upwind had far more difficulty in relocating Ascension Island, two eventually returning after 10 and 27 days and the third heading back to Brazil after failing to find its way back to the island. These findings strongly support the hypothesis that wind-borne cues are used by turtles to locate Ascension Island.  相似文献   
35.
L A Godley  F Lai  J Liu  N Zhao  M M Le Beau 《Genomics》1999,60(2):226-233
A deletion of the long arm of chromosome 5 is a recurring abnormality in malignant myeloid disorders. In previous studies, we identified an approximately 1-Mb segment in 5q31 that was deleted in all patients examined. As part of a positional cloning project to identify transcribed sequences in this region, we identified and characterized the TTID gene. This gene contains 10 exons that extend over 19 kb. The composite cDNA is approximately 2.3 kb and encodes a protein of 498 amino acids, with a predicted molecular mass of 55 kDa. The C-terminal half of this putative protein contains an internally repeated domain of 43 amino acids, which resembles the N-terminal half of an immunoglobulin domain from the immense skeletal muscle protein titin. The TTID gene is expressed in multiple muscle tissue types as well as in thyroid gland and bone marrow. We evaluated the gene as a candidate tumor suppressor gene by searching for mutations in malignant myeloid disorders with abnormalities of chromosome 5. However, we detected no inactivating mutations. A single nucleotide change (G to A) was identified at nucleotide position 1889 in the untranslated region of the mRNA, which may represent a polymorphism. Therefore, TTID is unlikely to be the candidate tumor suppressor gene involved in malignant myeloid disorders.  相似文献   
36.
We developed Ulysses as a user-oriented system that uses a process called Interolog Analysis for the parallel analysis and display of protein interactions detected in various species. Ulysses was designed to perform such Interolog Analysis by the projection of model organism interaction data onto homologous human proteins, and thus serves as an accelerator for the analysis of uncharacterized human proteins. The relevance of projections was assessed and validated against published reference collections. All source code is freely available, and the Ulysses system can be accessed via a web interface .  相似文献   
37.

Background  

We present Pegasys – a flexible, modular and customizable software system that facilitates the execution and data integration from heterogeneous biological sequence analysis tools.  相似文献   
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Protected areas are considered essential elements for global biodiversity conservation. They may not necessarily result in an effective conservation of resources in developing countries due to lack of funding for management and enforcement. In addition, poor governance aligned with conflicts of economic interests related to their use can further threaten their integrity and persistence. In the Dominican Republic, the western beaches of the Jaragua National Park (JNP), a protected area which is also part of a UNESCO Biosphere Reserve, have been proposed for development using a mass-tourism model. One of the most charismatic species found in this area is the leatherback turtle (Dermochelys coriacea). In the present study, we assess hatching success, and factors affecting it, to determine the reproductive value across the area for the leatherback turtle. The main factors found driving hatching success at the study beaches are beach sector, incubation duration, date of lay and clutch size. Our results show that clutches in La Cueva (located in the buffer zone of the park) and Bahía de las Águilas (located inside the limits of the park) have an unusually high hatching success (~75 %) for this species, highlighting the importance of increasing protection efforts at these sites. We strongly recommend including La Cueva inside the limits of the JNP.  相似文献   
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