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231.
232.
Nicholas E. C. Fleming Jonathan D. R. Houghton Caroline L. Magill Chris Harrod 《Marine Biology》2011,158(9):2141-2146
Jellyfish are increasingly topical within studies of marine food webs. Stable isotope analysis represents a valuable technique
to unravel the complex trophic role of these long-overlooked species. In other taxa, sample preservation has been shown to
alter the isotopic values of species under consideration, potentially leading to misinterpretation of trophic ecology. To
identify potential preservation effects in jellyfish, we collected Aurelia aurita from Strangford Lough (54o22′44.73″N, 5o32′53.44″W) during May 2009 and processed them using three different methods prior to isotopic analysis (unpreserved, frozen
and preserved in ethanol). A distinct preservation effect was found on δ15N values: furthermore, preservation also influenced the positive allometric relationship between individual size and δ15N values. Conversely, δ13C values remained consistent between the three preservation methods, conflicting with previous findings for other invertebrate,
fish and mammalian species. These findings have implications for incorporation of jellyfish into marine food webs and remote
sampling regimes where preservation of samples is unavoidable. 相似文献
233.
Sugimoto JD Labrique AB Ahmad S Rashid M Shamim AA Ullah B Klemm RD Christian P West KP 《Disasters》2011,35(2):329-345
The epidemiology of tornado-related disasters in the developing world is poorly understood. An August 2005 post-tornado cohort study in rural Bangladesh identified elevated levels of death and injury among the elderly (≥ 60 years of age) (adjusted odds ratio (AOR) = 8.9 (95 per cent confidence interval (CI): 3.9-20.2) and AOR = 1.6 (95 per cent CI: 1.4-1.8), respectively), as compared to 15-24 year-olds, and among those outdoors versus indoors during the tornado (AOR = 10.4 (95 per cent CI: 5.5-19.9) and AOR = 6.6 (95 per cent CI: 5.8-7.5), respectively). Females were 1.24 times (95 per cent CI: 1.15-1.33) more likely to be injured than males. Elevated risk of injury was significantly associated with structural damage to the house and tin construction materials. Seeking treatment was protective against death among the injured, odds ratio = 0.08 (95 per cent CI: 0.03-0.21). Further research is needed to develop injury prevention strategies and to address disparities in risk between age groups and between men and women. 相似文献
234.
The social spider Anelosimus studiosus exhibits a behavioral polymorphism where colony members express either a passive, tolerant behavioral tendency (social) or
an aggressive, intolerant behavioral tendency (asocial). Here we test whether asocial individuals act as colony defenders
by deflecting the suite of foreign (i.e., heterospecific) spider species that commonly exploit multi-female colonies. We (1)
determined whether the phenotypic composition of colonies is associated with foreign spider abundance, (2) tested whether
heterospecific spider abundance and diversity affect colony survival in the field, and (3) performed staged encounters between
groups of A. studiosus and their colony-level predator Agelenopsis emertoni (A. emertoni)to determine whether asocial females exhibit more defensive behavior. We found that larger colonies harbor more foreign spiders,
and the number of asocial colony members was negatively associated with foreign spider abundance. Additionally, colony persistence
was negatively associated with the abundance and diversity of foreign spiders within colonies. In encounters with a colony-level
predator, asocial females were more likely to exhibit escalatory behavior, and this might explain the negative association
between the frequency of asocial females and the presence of foreign spider associates. Together, our results indicate that
foreign spiders are detrimental to colony survival, and that asocial females play a defensive role in multi-female colonies. 相似文献
235.
Jonathan N. Pruitt Nicholas DiRienzo Simona Kralj-Fišer J. Chadwick Johnson Andrew Sih 《Behavioral ecology and sociobiology》2011,65(10):1987-1995
Research on consistent individual differences in behavior, or “behavioral syndromes”, continues to grow rapidly, and yet,
the aspects of behavior under consideration have remained remarkably limited. Here, we consider individual variation in consistency
of choice (termed here “choosiness”), as expressed during habitat choice. We repeatedly tested the responses of female Western
Black Widows, Latrodectus hesperus, to two cues of habitat quality: prey chemical cues and variation in web site illuminance. We estimated females’ response
by the distance they positioned themselves from (1) the source of prey chemical cues and (2) the darkest edge of our test
arena. Individuals with low variance in their responses are deemed more “choosy”, whereas individuals with high variance are
deemed less “choosy”. Generally, most females initiated web construction near the source of the prey chemical cues and tended
to place themselves in low-light conditions. However, we detected strong, repeatable differences in females’ intensity of
response, and within-individual variance of response (i.e., choosiness) was correlated across situations: females with highly
consistent responses towards cricket chemical cues also exhibited highly consistent responses towards variation in light conditions.
When deprived of food for extended periods, females were indistinguishable in their responses towards prey chemical cues,
but tended to initiate web construction in brighter lighting conditions. Food-deprived females universally exhibited higher
variance and diminished consistency in their responses (i.e., they were less choosy). Additionally, higher choosiness was
associated with greater mass loss during choice trials, suggesting choosiness is energetically costly. Our results demonstrate
that consistency of response to environmental cues is yet another element of behavior that varies among individuals and variation
in choosiness could beget speed/quality trade-offs during animal decision making. 相似文献
236.
Cat Button Maria Adelaida Antonette Mias-Mamonong Bernhard Barth Jonathan Rigg 《Local Environment》2013,18(6):705-722
Sorsogon City is a rapidly urbanising coastal area in the Philippines. Its location, combined with a rapidly changing and growing urban fabric, leaves it vulnerable to both incremental climate change and associated extreme weather events. In this paper, UN-HABITAT data are used to draw out the climate change vulnerabilities and policy responses in Sorsogon City. Vulnerability “hotspots” highlight the spatial intersection of socio-economic justice concerns, particularly in terms of vulnerability to increased cyclone activity. We discuss vulnerabilities of Sorsogon City and its citizens to climate change and measures undertaken through various social, environmental and technical systems and interventions to increase resilience. The paper also attempts to unpick the relationship between the neat, concise reported city and the complexities of urban life using the Sorsogon experiment to consider the limitations of such approaches to governing climate change. We group these under four headings: social simplification in the absence of data; over-governance (and under-representation); quick wins versus strategic investment; and stretching the ecological and vulnerability footprints of the city. The experience of Sorsogon City is then extended to reflect on issues of governance and planning in other Asian coastal cities. 相似文献
237.
238.
239.
Jonathan J. Waters Sally Walsh Lisa J. Levett Stuart Liddle Yinka Akinfenwa 《黑龙江环境通报》2006,26(10):892-897
A chorion villus sample (CVS) biopsied at 11 weeks' gestation for raised nuchal translucency, revealed monosomy X (presumptive 45,X karyotype) by QF-PCR for rapid aneuploidy testing for chromosomes 13, 18, 21, X and Y. Long-term culture gave the karyotype: 47,XY,+ 21[66]/49,XYY,+ 21,+ 21 [22]. This discrepancy prompted redigestion of the combined residual villus fragments from the original QF-PCR assay. The repeat QF-PCR assay identified the presence of trisomy 21 and a Y chromosome consistent with a 47,XY,+ 21 karyotype. A double non-disjunction event early in embryogenesis in a 47,XY,+ 21 conceptus with subsequent cell lineage compartmentalisation of the three observed cell lines (45,X; 47,XY,+ 21 and 49,XYY,+ 21,+ 21) would account for these results. This is the first reported case to describe complete discrepancy at diagnosis between abnormal karyotypes detected by QF-PCR rapid aneuploidy testing and a cultured karyotype in the same CVS. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
240.
Venom delivery systems occur in a wide range of extant and fossil vertebrates and are primarily based on oral adaptations.
Teeth range from unmodified (Komodo dragons) to highly specialized fangs similar to hypodermic needles (protero- and solenoglyphous
snakes). Developmental biologists have documented evidence for an infolding pathway of fang evolution, where the groove folds
over to create the more derived condition. However, the oldest known members of venomous clades retain the same condition
as their extant relatives, resulting in no fossil evidence for the transition. Based on a comparison of previously known specimens
with newly discovered teeth from North Carolina, we describe a new species of the Late Triassic archosauriform Uatchitodon and provide detailed analyses that provide evidence for both venom conduction and document a complete structural series from
shallow grooves to fully enclosed tubular canals. While known only from teeth, Uatchitodon is highly diagnostic in possessing compound serrations and for having two venom canals on each tooth in the dentition. Further,
although not a snake, Uatchitodon sheds light on the evolutionary trajectory of venom delivery systems in amniotes and provide solid evidence for venom conduction
in archosaur-line diapsids. 相似文献