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991.
992.
Elizabeth Grace Tunka Eronat 《Zoology in the Middle East.》2016,62(1):51-57
The feeding ecology of Chimaera monstrosa at a depth of 550?m was studied off S??ac?k Bay, Eastern Mediterranean, in 2008. Forty males and 57 females with a length between 7.80 and 45.5?cm were caught. 33 stomachs contained food items. The diet was composed of 11 prey items belonging to 6 groups: Bryozoa, Cnidaria, Crustacea, Mollusca, Tunicata, and Teleostei, of which Crustacea (IRI% [Index of Relative Importance]=80) and Mollusca (IR%=16) were the most abundant prey groups. The trophic level was estimated at 3.50, which is similar to the results from other studies in the western and northern part of the Mediterranean and the Atlantic Ocean but is higher than in the North Sea. 相似文献
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994.
Grace E. Vincent Brad Aisbett Sarah J. Hall Sally A. Ferguson 《Chronobiology international》2016,33(6):657-666
ABSTRACTPlanned burning is a preventative strategy aimed at decreasing fuel loads to reduce the severity of future wildfire events. During planned burn operations, firefighters can work long shifts. Furthermore, remote burning locations may require firefighters to sleep away from home between shifts. The existing evidence surrounding firefighters’ sleep during such operations is exclusively anecdotal. The aims of the study were to describe firefighters’ sleep during planned burn operations and evaluate the impact of the key operational factors (shift start time, shift length and sleeping location) that may contribute to inadequate sleep. Thirty-three salaried firefighters were recruited from Australia’s fire agencies and sleep was measured objectively using wrist actigraphy for four weeks. All variables were examined in two conditions: (1) burn days, and (2) non-burn days. Time in bed, total sleep time, sleep latency and sleep efficiency were evaluated objectively. Subjective reports of pre- and post-sleep fatigue, sleep location, sleep quality, sleep quantity, number of times woken and sleep timing were also recorded. Analyses revealed no differences in measures of sleep quantity and quality when comparing non-burn and burn days. Total sleep time was less when planned burn shifts were >12 h. However, on burn days, work shift start time as well as sleeping location did not impact firefighters’ sleep quantity. Self-reported levels of pre- and post-sleep fatigue were greater on burn days compared to non-burn days. These findings indicate that sleep quantity and quality are not compromised during planned burn operations <12 h in duration. 相似文献
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996.
Fast‐scan cyclic voltammetry demonstrates that L‐DOPA produces dose‐dependent,regionally selective bimodal effects on striatal dopamine kinetics in vivo
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997.
998.
Disentangling vegetation diversity from climate–energy and habitat heterogeneity for explaining animal geographic patterns
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Borja Jiménez‐Alfaro Milan Chytrý Ladislav Mucina James B. Grace Marcel Rejmánek 《Ecology and evolution》2016,6(5):1515-1526
Broad‐scale animal diversity patterns have been traditionally explained by hypotheses focused on climate–energy and habitat heterogeneity, without considering the direct influence of vegetation structure and composition. However, integrating these factors when considering plant–animal correlates still poses a major challenge because plant communities are controlled by abiotic factors that may, at the same time, influence animal distributions. By testing whether the number and variation of plant community types in Europe explain country‐level diversity in six animal groups, we propose a conceptual framework in which vegetation diversity represents a bridge between abiotic factors and animal diversity. We show that vegetation diversity explains variation in animal richness not accounted for by altitudinal range or potential evapotranspiration, being the best predictor for butterflies, beetles, and amphibians. Moreover, the dissimilarity of plant community types explains the highest proportion of variation in animal assemblages across the studied regions, an effect that outperforms the effect of climate and their shared contribution with pure spatial variation. Our results at the country level suggest that vegetation diversity, as estimated from broad‐scale classifications of plant communities, may contribute to our understanding of animal richness and may be disentangled, at least to a degree, from climate–energy and abiotic habitat heterogeneity. 相似文献
999.
With increasing urbanization, urban‐fragmented landscapes are becoming more and more prevalent worldwide. Such fragmentation may lead to small, isolated populations that face great threats from genetic factors that affect even avian species with high dispersal propensities. Yet few studies have investigated the population genetics of species living within urban‐fragmented landscapes in the Old World tropics, in spite of the high levels of deforestation and fragmentation within this region. We investigated the evolutionary history and population genetics of the olive‐winged bulbul (Pycnonotus plumosus) in Singapore, a highly urbanized island which retains <5% of its original forest cover in fragments. Combining our own collected and sequenced samples with those from the literature, we conducted phylogenetic and population genetic analyses. We revealed high genetic diversity, evidence for population expansion, and potential presence of pronounced gene flow across the population in Singapore. This suggests increased chances of long‐term persistence for the olive‐winged bulbul and the ecosystem services it provides within this landscape. 相似文献
1000.
Rainer W. Bussmann Narel Y. Paniagua-Zambrana Nick Wood Sankairi Ole Njapit James Nkiingis Ole Njapit Grace Sorimpan Ene Osoi Simon Pariken Kasoe 《Economic botany》2018,72(2):207-216
Traditional plant use is of tremendous importance in many societies, including most rural African communities. A variety of studies have shown knowledge dwindling due to changes towards a more Western lifestyle, and the influence of modern tourism. In the case of the Sekenani Maasai, we hypothesized in 2006 that, while little knowledge loss had been observed at that time, the change from a nomadic to a more sedentary lifestyle would lead to an accelerating loss of traditional plant knowledge. This paper examines the plant use of the Maasai in the Sekenani Valley, North of the Maasai Mara National Reserve 15 years after a first study. Based on the study of 2002 (Bussmann et al. Journal of Ethnobiology and Ethnomedicine 2: 22, 2006), semi-structured interviews were conducted with staff of Sekenani Camp in order to document current plant knowledge. The results of this follow-up study indicate dramatic knowledge loss over the last 15 years. Of 139 used species documented in 2002, only 84 remained in use in 2017. Off those species still in use, 30 had experienced a loss of uses, while for 18 species new uses were documented. The knowledge loss observed in Sekenani in 15 years is rather dramatic. Lifestyle changes and over-use of resources have clearly led to a rapid decline of traditional knowledge on plant use. This trend is expected to continue. 相似文献