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1.
It is more than half a century since Frederick G. G. Rose (1915–1991) published his classic text, The classification of kin, age structure and marriage amongst the Groote Eylandt Aborigines: A study in method and a theory of kinship (1960) in the former German Democratic Republic. Although the fieldwork for his thesis had been carried out in Australia on Groote Eylandt in 1938 and 1941, a conservative academic establishment and the political climate of the Cold War postponed its publication until 1960. Why were Rose's fieldwork findings suppressed by the powerful gate-keeper of Australian anthropology, Professor Adolphus Peter Elkin (1891–1979)? Moreover, why was Rose later denied a government permit to revisit Groote Eylandt and Central Australia to further his research? This paper examines the early work of the communist anthropologist, Frederick Rose, within the broad context of Western post-war anthropological developments, an expanding capitalist economy and the political tensions of the Cold War era. As a communist and public servant from 1938 to 1954, Rose was forced, after the Petrov Royal Commission cast him under a cloud of suspicion, to seek institutional support for his academic career in the German Democratic Republic.  相似文献   
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The mountain pine beetle (MPB) is a native bark beetle of western North America that attacks pine tree species, particularly lodgepole pine. It is closely associated with the ophiostomatoid ascomycetes Grosmannia clavigera, Leptographium longiclavatum, Ophiostoma montium, and Ceratocystiopsis sp.1, with which it is symbiotically associated. To develop a better understanding of interactions between beetles, fungi, and host trees, we used target-specific DNA primers with qPCR to assess the changes in fungal associate abundance over the stages of the MPB life cycle that occur in galleries under the bark of pine trees. Multivariate analysis of covariance identified statistically significant changes in the relative abundance of the fungi over the life cycle of the MPB. Univariate analysis of covariance identified a statistically significant increase in the abundance of Ceratocystiopsis sp.1 through the beetle life cycle, and pair-wise analysis showed that this increase occurs after the larval stage. In contrast, the abundance of O. montium and Leptographium species (G. clavigera, L. longiclavatum) did not change significantly through the MPB life cycle. From these results, the only fungus showing a significant increase in relative abundance has not been formally described and has been largely ignored by other MPB studies. Although our results were from only one site, in previous studies we have shown that the fungi described were all present in at least ten sites in British Columbia. We suggest that the role of Ceratocystiopsis sp.1 in the MPB system should be explored, particularly its potential as a source of nutrients for teneral adults.  相似文献   
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Understanding ectomycorrhizal fungal (EMF) community structure is limited by a lack of taxonomic resolution and autecological information. Rhizopogon vesiculosus and Rhizopogon vinicolor (Basidiomycota) are morphologically and genetically related species. They are dominant members of interior Douglas‐fir (Pseudotsuga menziesii var. glauca) EMF communities, but mechanisms leading to their coexistence are unknown. We investigated the microsite associations and foraging strategy of individual R. vesiculosus and R. vinicolor genets. Mycelia spatial patterns, pervasiveness and root colonization patterns of fungal genets were compared between Rhizopogon species and between xeric and mesic soil moisture regimes. Rhizopogon spp. mycelia were systematically excavated from the soil and identified using microsatellite DNA markers. Rhizopogon vesiculosus mycelia occurred at greater depth, were more spatially pervasive, and colonized more tree roots than R. vinicolor mycelia. Both species were frequently encountered in organic layers and between the interface of organic and mineral horizons. They were particularly abundant within microsites associated with soil moisture retention. The occurrence of R. vesiculosus shifted in the presence of R. vinicolor towards mineral soil horizons, where R. vinicolor was mostly absent. This suggests that competition and foraging strategy may contribute towards the vertical partitioning observed between these species. Rhizopogon vesiculosus and R. vinicolor mycelia systems occurred at greater mean depths and were more pervasive in mesic plots compared with xeric plots. The spatial continuity and number of trees colonized by genets of each species did not significantly differ between soil moisture regimes.  相似文献   
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Volatile compounds contribute substantially to the metabolic pool in man. Their analysis in body fluids is problematic. We investigated headspace solid-phase microextraction (HS-SPME) with Carboxen–polydimethylsiloxane fibres and gas chromatography–mass spectrometry for profiling urinary volatile components. These fibres were more sensitive for very volatile and sulfur compounds than three other phases tested. We detected a wide range of compounds in normal urine at acid and alkaline pH. Profiles presented for five individuals with metabolic disturbances demonstrate abnormal accumulation of sulfur compounds, fatty acids and plasticisers. HS-SPME can complement profiling of non-volatile compounds in metabolic investigations and could be a useful extension of the diagnostic repertoire.  相似文献   
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Heterogeneous exposure to mosquitoes determines an individual’s contribution to vector-borne pathogen transmission. Particularly for dengue virus (DENV), there is a major difficulty in quantifying human-vector contacts due to the unknown coupled effect of key heterogeneities. To test the hypothesis that the reduction of human out-of-home mobility due to dengue illness will significantly influence population-level dynamics and the structure of DENV transmission chains, we extended an existing modeling framework to include social structure, disease-driven mobility reductions, and heterogeneous transmissibility from different infectious groups. Compared to a baseline model, naïve to human pre-symptomatic infectiousness and disease-driven mobility changes, a model including both parameters predicted an increase of 37% in the probability of a DENV outbreak occurring; a model including mobility change alone predicted a 15.5% increase compared to the baseline model. At the individual level, models including mobility change led to a reduction of the importance of out-of-home onward transmission (R, the fraction of secondary cases predicted to be generated by an individual) by symptomatic individuals (up to -62%) at the expense of an increase in the relevance of their home (up to +40%). An individual’s positive contribution to R could be predicted by a GAM including a non-linear interaction between an individual’s biting suitability and the number of mosquitoes in their home (>10 mosquitoes and 0.6 individual attractiveness significantly increased R). We conclude that the complex fabric of social relationships and differential behavioral response to dengue illness cause the fraction of symptomatic DENV infections to concentrate transmission in specific locations, whereas asymptomatic carriers (including individuals in their pre-symptomatic period) move the virus throughout the landscape. Our findings point to the difficulty of focusing vector control interventions reactively on the home of symptomatic individuals, as this approach will fail to contain virus propagation by visitors to their house and asymptomatic carriers.  相似文献   
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Valerie  Standen 《Journal of Zoology》1970,161(2):461-470
The methods are given which were used to determine the number of stages in the life history of Trichoniscus pusillus pusillus Brandt, 1833 and the stages are described as far as possible. Not all stadia can be separated on morphological grounds and animals extracted from monthly litter samples were measured and the stadia separated by use of probability paper. This method proved quite successful and confirmed the characterization of the three earlier juvenile stadia on morpholigical grounds and the number of the later juvenile stadia determined from laboratory cultures. There are six juvenile and five adult stadia.  相似文献   
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Hybridization between the viviparous fishes Poeciliopsis monacha and P. lucida of northwestern Mexico has resulted in the formation of diploid and triploid all-female ‘species’, P. monacha-lucida and P. monacha-2 lucida. These females reproduce by mating back to P. lucida, and are essentially clonally reproducing sexual parasites superimposed on that species. In a series of behavioural experiments, one diploid clone proved to be significantly more aggressive than one triploid and four other diploid clones. No differences in aggression were exhibited among the other five clones. The aggressiveness of this one clone may explain why only two clones live in the small tributary where it is found but up to 10 diploid and triploid clones occur where it is absent.  相似文献   
10.
Using molecular dynamics simulations and steady‐state fluorescence spectroscopy, we have identified a conformational change in the active site of a thermophilic flavoenzyme, NADH oxidase from Thermus thermophilus HB8 (NOX). The enzyme's far‐UV circular dichroism spectrum, intrinsic tryptophan fluorescence, and apparent molecular weight measured by dynamic light scattering varied little between 25 and 75°C. However, the fluorescence of the tightly bound FAD cofactor increased approximately fourfold over this temperature range. This effect appears not to be due to aggregation, unfolding, cofactor dissociation, or changes in quaternary structure. We therefore attribute the change in flavin fluorescence to a temperature‐dependent conformational change involving the NOX active site. Molecular dynamics simulations and the effects of mutating aromatic residues near the flavin suggest that the change in fluorescence results from a decrease in quenching by electron transfer from tyrosine 137 to the flavin. Proteins 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
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