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The important requirement that COST Action 730 demanded of the physiological model to be used for the Universal Thermal Climate Index (UTCI) was its capability of accurate simulation of human thermophysiological responses across a wide range of relevant environmental conditions, such as conditions corresponding to the selection of all habitable climates and their seasonal changes, and transient conditions representing the temporal variation of outdoor conditions. In the first part of this study, available heat budget/two-node models and multi-node thermophysiological models were evaluated by direct comparison over a wide spectrum of climatic conditions. The UTCI-Fiala model predicted most reliably the average human thermal response, as shown by least deviations from physiologically plausible responses when compared to other models. In the second part of the study, this model was subjected to extensive validation using the results of human subject experiments for a range of relevant (steady-state and transient) environmental conditions. The UTCI-Fiala multi-node model proved its ability to predict adequately the human physiological response for a variety of moderate and extreme conditions represented in the COST 730 database. The mean skin and core temperatures were predicted with average root-mean-square deviations of 1.35 ± 1.00°C and 0.32 ± 0.20°C, respectively.  相似文献   

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Universal immunoprobe for (per)chlorate-reducing bacteria   总被引:1,自引:0,他引:1  
Recent studies in our lab have demonstrated the ubiquity and diversity of microorganisms which couple growth to the reduction of chlorate or perchlorate [(per)chlorate] under anaerobic conditions. We identified two taxonomic groups, the Dechloromonas and the Dechlorosoma groups, which represent the dominant (per)chlorate-reducing bacteria (ClRB) in the environment. As part of these studies we demonstrated that chlorite dismutation is a central step in the reductive pathway of (per)chlorate that is common to all ClRB and which is mediated by the enzyme chlorite dismutase (CD). Initial studies on CD suggested that this enzyme is highly conserved among the ClRB, regardless of their phylogenetic affiliation. As such, this enzyme makes an ideal target for a probe specific for these organisms. Polyclonal antibodies were commercially raised against the purified CD from the ClRB Dechloromonas agitata strain CKB. The obtained antiserum was deproteinated by ammonium sulfate precipitation, and the antigen binding activity was assessed using dot blot analysis of a serial dilution of the antiserum. The titers obtained with purified CD indicated that the antiserum had a high affinity for the CD enzyme, and activity was observed in dilutions as low as 10(-6) of the original antiserum. The antiserum was active against both cell lysates and whole cells of D. agitata, but only if the cells were grown anaerobically with (per)chlorate. No response was obtained with aerobically grown cultures. In addition to D. agitata, dot blot analysis employed with both whole-cell suspensions and cell lysates of several diverse ClRB representing the alpha, beta, and gamma subclasses of Proteobacteria tested positive regardless of phylogenetic affiliation. Interestingly, the dot blot response obtained for each of the ClRB cell lysates was different, suggesting that there may be some differences in the antigenic sites of the CD protein produced in these organisms. In general, no reactions were observed with cells or cell lysates of the organisms closely related to the ClRB which could not grow by (per)chlorate reduction. These studies have resulted in the development of a highly specific and sensitive immunoprobe based on the commonality of the CD enzyme in ClRB which can be used to assess dissimilatory (per)chlorate-reducing populations in environmental samples regardless of their phylogenetic affiliations.  相似文献   

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福建省马尾松叶面积指数对气候的响应   总被引:1,自引:0,他引:1  
掌握马尾松叶面积指数(LAI)的时空分布规律是实现马尾松毛虫害空间监测与预警的基础要求。以福建省38个气候台站测定的2010年平均气温、平均气温距平、降雨量、降雨量距平、日照时数及日照时数距平等6个气候要素及实地测定的90个马尾松LAI数据为基础,分别从省域、地市两个尺度分析了福建省马尾松LAI对气候的响应规律。结果表明:(1)除日照时数距平外,其他5个气候要素对马尾松LAI均有显著影响,相关系数排序为:平均气温〉降雨量〉日照时数〉平均气温距平〉降雨量距平;(2)从省域尺度上看,马尾松LAI对平均气温的响应呈开口向下的抛物线,对平均气温距平的响应可以用三次曲线较好地予以说明;LAI对降雨量的响应是负向的,降雨量距平对LAI的影响与平均温度相似;对日照时数的响应则呈开头向上的抛物线;(3)从地市尺度上看,马尾松主产区南平、三明、龙岩3市的LAI普遍低于沿海非主产区,尤以南平最低,一方面是由于马尾松LAI对气候要素的直接响应,另一方面则是通过气候对松毛虫分布的影响,使LAI呈现沿海高、内陆低的空间特征。  相似文献   

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Attempts to design truly universal primers to amplify chloroplast microsatellites have met with limited success due to nonconservation of repeat loci across widely divergent taxa. We have used the complete chloroplast genome sequences of rice, maize and wheat to design five pairs of primers that amplify homologous mononucleotide repeats across the Poaceae (grasses). Sequencing confirmed conservation of repeat motifs across subfamilies and a preliminary study in Anthoxanthum odoratum revealed polymorphism at two loci with a haplotype diversity value of 0.495. These primers provide a valuable tool to study cytoplasmic diversity in this extensively studied and economically important range of taxa.  相似文献   

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The development of universal markers that can be assayed across taxa, but which are polymorphic within taxa, can facilitate both comparative map-based studies and phylogenetic analyses. Here we describe the development of such markers for use in the Asteraceae, which includes the crops lettuce, sunflower, and safflower as well as dozens of locally important crop and weed species. Using alignments of a conserved orthologous set (COS) of ESTs from lettuce and sunflower and genomic sequences of Arabidopsis, we designed a suite of primer pairs that are conserved across species, but which are predicted to flank introns. We then tested 192 such primer pairs in 8 species from across the family. Of these, 163 produced an amplicon in at least 1 taxon, and 125 amplified in at least half of the taxa surveyed. Thirty-nine amplified in all 8 species. Comparisons amongst sequences within the lettuce and sunflower EST databases indicate that the vast majority of these loci will be polymorphic. As a direct test of the utility of these markers outside the lettuce and sunflower subfamilies, we sequenced a subset of ten loci from a panel of cultivated safflower individuals. All 10 loci proved to be single-locus, and nine of the 10 loci were polymorphic with an average of 12.8 SNPs per kb. Taken together, these loci will provide an initial backbone for comparative genetic analyses within the Asteraceae. Moreover, our results indicate that these loci are phylogenetically informative, and hence can be used to resolve evolutionary relationships between taxa within the family as well as within species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Mark A. Chapman and JianCheng Chang have contributed equally to this work.  相似文献   

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Lipoprotein(a) [Lp(a)] is a low-density lipoprotein-like particle displaying strong athero-thrombotic properties. Highly purified Lp(a) is increasingly requested for standardization of Lp(a) measurements and for biological studies. Several procedures have been described for Lp(a) separation and purification but none of them appear completely suitable. We present here a procedure for Lp(a) purification based on sequential elutions after lysine-Sepharose affinity chromatography. We were able to identify four distinct subspecies of Lp(a) showing different affinity to ε-amino groups of lysine-Sepharose, simply by modifying molarity and pH of the eluents; the fraction obtained in highly purified state represented the major form and could be eluted with 0.5 M sodium phosphate buffer (pH 4.4). Advantages of this procedure are represented by simplicity, rapidity and final yield.  相似文献   

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Background

Mere possibility is not an adequate basis for asserting scientific plausibility. A precisely defined universal bound is needed beyond which the assertion of plausibility, particularly in life-origin models, can be considered operationally falsified. But can something so seemingly relative and subjective as plausibility ever be quantified? Amazingly, the answer is, "Yes." A method of objectively measuring the plausibility of any chance hypothesis (The Universal Plausibility Metric [UPM]) is presented. A numerical inequality is also provided whereby any chance hypothesis can be definitively falsified when its UPM metric of ξ is < 1 (The Universal Plausibility Principle [UPP]). Both UPM and UPP pre-exist and are independent of any experimental design and data set.

Conclusion

No low-probability hypothetical plausibility assertion should survive peer-review without subjection to the UPP inequality standard of formal falsification (ξ < 1).  相似文献   

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We have devised a novel method for automated microsatellite analysis using "universal" fluorescent labeling. This system is based on polymerase chain reactions driven by sequence-specific primers and a reporter primer labeled with a fluorescent dye at its 5' end. The forward sequence-specific primer is designed with a tag region bearing no homology to any human genomic sequence. Complementary tag sequences act as templates for the 6-carboxyfluorescein-labeled reporter primer, and those products can be analyzed with an autosequencer. The results we achieved with this assay system were consistent with the results of conventional assays using radioisotope-labeled primers, and diagnosis required less time. Furthermore, the fluorescent-labeled reporter primer is "universal" in that it can be used with different sequence-specific primers designed to carry the appropriate tag sequence at their 5'-ends. Our observations suggest that the "universal" fluorescent labeling method is an efficient tool for analyzing sequence variations in human DNA.  相似文献   

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Global climate change may become one of the most pressing challenges to Pacific Salmon conservation and management for southeast Alaska in the 21st Century. Predicted hydrologic change associated with climate change will likely challenge the ability of specific stocks to adapt to new flow regimes and resulting shifts in spawning and rearing habitats. Current research suggests egg-to-fry survival may be one of the most important freshwater limiting factors in Pacific Salmon''s northern range due to more frequent flooding events predicted to scour eggs from mobile spawning substrates. A watershed-scale hydroclimatic sensitivity index was developed to map this hypothesis with an historical stream gauge station dataset and monthly multiple regression-based discharge models. The relative change from present to future watershed conditions predicted for the spawning and incubation period (September to March) was quantified using an ensemble global climate model average (ECHAM5, HadCM3, and CGCM3.1) and three global greenhouse gas emission scenarios (B1, A1B, and A2) projected to the year 2080. The models showed the region''s diverse physiography and climatology resulted in a relatively predictable pattern of change: northern mainland and steeper, snow-fed mountainous watersheds exhibited the greatest increases in discharge, an earlier spring melt, and a transition into rain-fed hydrologic patterns. Predicted streamflow increases for all watersheds ranged from approximately 1-fold to 3-fold for the spawning and incubation period, with increased peak flows in the spring and fall. The hydroclimatic sensitivity index was then combined with an index of currently mapped salmon habitat and species diversity to develop a research and conservation priority matrix, highlighting potentially vulnerable to resilient high-value watersheds. The resulting matrix and observed trends are put forth as a framework to prioritize long-term monitoring plans, mitigation experiments, and finer-scale climate impact and adaptation studies.  相似文献   

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