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41.
Nationalism and its counterpart, modernism, are projects that involve the attempt to homogenize and incorporate the masses through the creation of a majority identity that usually leads to the classification of certain deviant groups as ‘others’. In Spain, civic and ethnic nationalisms driven by the state have historically drawn on cultural and biological notions of ethnicity and race to construct a representation of the Maragatos as ‘cursed peoples’, while at the same time homogenizing and incorporating them into the nation in practice. By tracing a genealogy of the origins and evolution of the representations of Maragato otherness created during the Enlightenment era, the Franco dictatorship and the current super-modern period, this paper argues that representations of otherness significantly influence current research agendas and understandings of identity well beyond the disappearance of the actual subjects described as others.  相似文献   
42.
Microcebus murinus, a small nocturnal Malagasy primate, exhibits adaptive energy-saving strategies such as daily hypothermia and gregarious patterns during diurnal rest. To determine whether ambient temperature (Ta), food restriction and nest sharing can modify the daily body temperature (Tb) rhythm, Tb was recorded by telemetry during winter in six males exposed to different ambient temperatures (Ta=25, 20, 15°C) and/or to a total food restriction for 3 days depending on social condition (isolated versus pair-grouped). At 25°C, the daily rhythm of Tb was characterized by high Tb values during the night and lower values during the day. Exposure to cold significantly decreased minimal Tb values and lengthened the daily hypothermia. Under food restriction, minimal Tb values were also markedly lowered. The combination of food restriction and cold induced further increases in duration and depth of torpor bouts, minimal Tb reaching a level just above Ta. Although it influenced daily hypothermia less than environmental factors, nest sharing modified effects of cold and food restriction previously observed by lengthening duration of torpor but without increasing its depth. In response to external conditions, mouse lemurs may thus adjust their energy expenditures through daily modifications of both the duration and the depth of torpor.  相似文献   
43.
Reading, writing, publishing, and publicly presenting scientific works are vital for a young researcher's profile building and career development. Generally, the traditional educational curricula do not offer training possibilities to learn and practice how to prepare, write, and present scientific works. These are rather a part of lab meeting activities in research groups. The lack of such training is more critical in some developing countries because this adds to the rare opportunities to discuss and become involved in the exchanges on state of the art scientific literature. Here the authors relate their experience in introducing a weekly 1-day lab meeting in the framework of two previously organized 3-month courses on “Bioinformatics and Genome Analyses”. The main activities which are developed during these lab meetings include scientific literature follow up as well as preparing and presenting oral and written scientific reviews. These activities prove to be useful for a student's self-confidence building, for enhancing their active participation during the lectures and practical sessions, as well as for the positive impact on running the whole course program. Incorporation of such lab meeting activities in the course program significantly improves the capacity building of the participants, their analytical and critical reading of scientific literature, as well as communication skills. In this work it is shown how to proceed with the different steps involved in the implementation of lab meeting activities, and to recommend their regular institution in similar courses.  相似文献   
44.
Aims:  To identify a toxin and its producer isolated from woody material in a building where the occupants experienced serious ill health symptoms.
Methods and Results:  Hyphal extracts of an indoor fungus, identified as the cycloheximide-tolerant species Acremonium exuviarum , inhibited motility of boar spermatozoa (EC50 5 ± 2 μg of crude solids ml−1) and caused cytolysis of murine neuroblastoma cells (MNA) and feline fetal lung cells (FL). The responsible substances were purified and identified as two structurally similar, heat-stable, novel, toxic peptaibols, 1726 Da and 1740 Da, respectively, with amino acid sequences of Acetyl-Phe-Iva/Val-Gln-Aib-Ile-Thr-Leu-Aib-Pro-Aib-Gln-Pro-Aib-(X-X-X)-SerOH and Acetyl-Phe-Iva/Val-Gln-Aib-Ile-Thr-Leu-Val-Pro-Aib-Gln-Pro-Aib-(X-X-X)-SerOH. Purified acrebol inhibited motility of boar sperm, depleted ATP half-content in 1 day (EC50 of 0·1 μg ml−1, 60 nmol l−1) depolarised the mitochondria after 2 days, but did not affect the cellular content in NADH. This indicates mitochondrial toxicity. Plate-grown biomass of A. exuviarum BMB4 contained 0·1–1% (w/w) of acrebol, depending on the culture medium.
Conclusions:  Acrebol paralysed the energy generation of mammalian cells suggesting that mitochondria were its target of action.
Significance and Impact of the Study:  Acremonium exuviarum, as an indoor fungus, is potentially hazardous to health because of the toxic peptaibols that it produces.  相似文献   
45.
Carbon stored in human settlements: the conterminous United States   总被引:6,自引:0,他引:6  
Urban areas are home to more than half of the world's people, responsible for >70% of anthropogenic release of carbon dioxide and 76% of wood used for industrial purposes. By 2050 the proportion of the urban population is expected to increase to 70% worldwide. Despite fast rates of change and potential value for mitigation of carbon dioxide emissions, the organic carbon storage in human settlements has not been well quantified. Here, we show that human settlements can store as much carbon per unit area (23–42 kg C m−2 urban areas and 7–16 kg C m−2exurban areas) as tropical forests, which have the highest carbon density of natural ecosystems (4–25 kg C m−2). By the year 2000 carbon storage attributed to human settlements of the conterminous United States was 18 Pg of carbon or 10% of its total land carbon storage. Sixty-four percent of this carbon was attributed to soil, 20% to vegetation, 11% to landfills, and 5% to buildings. To offset rising urban emissions of carbon, regional and national governments should consider how to protect or even to increase carbon storage of human-dominated landscapes. Rigorous studies addressing carbon budgets of human settlements and vulnerability of their carbon storage are needed.  相似文献   
46.
河北唐海湿地四种鹭的种群动态和繁殖空间生态位   总被引:1,自引:0,他引:1  
2004年8月—2005年7月对河北唐海湿地夜鹭(Nycticoraxnycticorax)、白鹭(Egtettagarzetta)、池鹭(Ardeolabacchus)、大白鹭(Casmerodiusalbus)的种群动态和繁殖行为进行了观察,并对巢群关系进行了研究。统计了4种鹭垂直和水平巢位的巢密度,计算了不同种鹭巢的生态位重叠、生态位宽度值。结果4种鹭在唐海数量最多月份为4—9月,最大量达到了近5800只。共有Ⅰ、Ⅱ两个巢区,迁来Ⅱ区时间较Ⅰ区晚半个月左右。除池鹭外,3种鹭之间均有争巢现象,后期趋于稳定。迫于密度压力和竞争,部分白鹭和池鹭取食范围较广。除大白鹭外,其他3种鹭同种间均有混交现象。在混巢区,夜鹭迁来最早,数量最大,为优势种,多数占据中心区的顶巢;大白鹭数量最少,亦占据中心区的顶巢;白鹭迁来较晚,占据中位巢;池鹭迁来最晚,数量较白鹭少,多数在边缘区单独筑巢,少数在中心区占下位巢。白鹭巢的垂直生态位最宽;夜鹭巢的水平生态位最宽;池鹭巢的综合空间生态位最宽。池鹭和夜鹭巢位的空间格局最为相似,池鹭和白鹭的生态位重叠较大。夜鹭的数量最多、大白鹭的个体最大,导致其处于优势;白鹭和池鹭数量少、个体小,导致其处于劣势。唐海湿地内丰富的食物和适宜的林带是鹭鸟密度较大的主要原因。此外,鹭类只筑巢在散布的、双行杨树林带均高为22m以上区域,是该地鹭类巢区的主要特点。  相似文献   
47.
Iris validation is a Python package created to represent comprehensive per‐residue validation metrics for entire protein chains in a compact, readable and interactive view. These metrics can either be calculated by Iris, or by a third‐party program such as MolProbity. We show that those parts of a protein model requiring attention may generate ripples across the metrics on the diagram, immediately catching the modeler's attention. Iris can run as a standalone tool, or be plugged into existing structural biology software to display per‐chain model quality at a glance, with a particular emphasis on evaluating incremental changes resulting from the iterative nature of model building and refinement. Finally, the integration of Iris into the CCP4i2 graphical user interface is provided as a showcase of its pluggable design.  相似文献   
48.
Current statistical methods for estimating nest survival rates assume that nests are identical in their propensity to succeed. However, there are several biological reasons to question this assumption. For example, experience of the nest builder, number of nest helpers, genetic fitness of individuals, and site effects may contribute to an inherent disparity between nests with respect to their daily mortality rates. Ignoring such heterogeneity can lead to incorrect survival estimates. Our results show that constant survival models can seriously underestimate overall survival in the presence of heterogeneity. This paper presents a flexible random-effects approach to model heterogeneous nest survival data. We illustrate our methods through data on redwing blackbirds.  相似文献   
49.
Hirabayashi  Kimio  Wotton  Roger S. 《Hydrobiologia》1998,382(1-3):151-159
In laboratory experiments, we used fluorescent dye markers to investigate processing of organic matter by larvae of Psectrocladius limbatellus (Holm.) (Diptera: Chironomidae). 59% of the organic matter used was incorporated into tubes, 39% was present in faecal pellets (both after 24 h), and 2% was found in the larval gut at the end of experiments. Ingested matter passed through the gut rapidly, resulting in the gut being emptied more than 20 times each day. Further 24-h experiments using dye-marked faecal pellets showed that 6% of pellets produced were re-ingested and 12% were incorporated into tubes. There was no preference for conditioned faecal pellets as food over those that had recently been egested and tubes also provided a food reserve on which larvae feed. Chironomid larvae recycle organic matter resulting in its mineralization and their ‘engineering’ has a dramatic effect on the substratum. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
50.
The use of models to predict indoor air quality and health risk for the soil vapor transport to indoor air pathway is commonplace; however, there is significant uncertainty surrounding processes and factors affecting this pathway, and the accuracy of models used. Available screening models were evaluated through a review of model characteristics and sensitivity, and through comparisons to measured conditions at field sites. Model simulations and comparisons to field data indicate that the vapor attenuation ratio (α) is highly sensitive to certain processes (e.g., biodegradation and ad-vection) and input parameters. Comparisons of model predicted to measured a values indicate that models based on the Johnson and Ettinger (1991) framework in most cases result in predictions that are conservative by up to one to two orders of magnitude for field sites that were assessed, providing that appropriate input parameters are used. However, for sites where the advection potential is high, these models may not be conservative. The potential for advective transport of vapors into building may be significant for sites with shallow contamination, high permeability soil and foundation and high building underpressurization. The paper concludes with possible tiered management framework for the soil vapor pathway.  相似文献   
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