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排序方式: 共有322条查询结果,搜索用时 125 毫秒
21.
Meijaard E Mengersen K Buchori D Nurcahyo A Ancrenaz M Wich S Atmoko SS Tjiu A Prasetyo D Nardiyono Hadiprakarsa Y Christy L Wells J Albar G Marshall AJ 《PloS one》2011,6(3):e18008
Species conservation is difficult. Threats to species are typically high and immediate. Effective solutions for counteracting these threats, however, require synthesis of high quality evidence, appropriately targeted activities, typically costly implementation, and rapid re-evaluation and adaptation. Conservation management can be ineffective if there is insufficient understanding of the complex ecological, political, socio-cultural, and economic factors that underlie conservation threats. When information about these factors is incomplete, conservation managers may be unaware of the most urgent threats or unable to envision all consequences of potential management strategies. Conservation research aims to address the gap between what is known and what knowledge is needed for effective conservation. Such research, however, generally addresses a subset of the factors that underlie conservation threats, producing a limited, simplistic, and often biased view of complex, real world situations. A combination of approaches is required to provide the complete picture necessary to engage in effective conservation. Orangutan conservation (Pongo spp.) offers an example: standard conservation assessments employ survey methods that focus on ecological variables, but do not usually address the socio-cultural factors that underlie threats. Here, we evaluate a complementary survey method based on interviews of nearly 7,000 people in 687 villages in Kalimantan, Indonesia. We address areas of potential methodological weakness in such surveys, including sampling and questionnaire design, respondent biases, statistical analyses, and sensitivity of resultant inferences. We show that interview-based surveys can provide cost-effective and statistically robust methods to better understand poorly known populations of species that are relatively easily identified by local people. Such surveys provide reasonably reliable estimates of relative presence and relative encounter rates of such species, as well as quantifying the main factors that threaten them. We recommend more extensive use of carefully designed and implemented interview surveys, in conjunction with more traditional field methods. 相似文献
22.
Campylobacter jejuni is the leading cause of food-borne gastro-enteritis and infection can be followed by severe clinical complications, such as the autoimmune neuropathy Guillain–Barré syndrome. Poultry meat is considered to be a common source of infection, with most flocks infected from 2 to 3 weeks of age. We have examined the effect of host genetics on the colonisation levels of C. jejuni in chickens. Chicks from different inbred lines were challenged with 107 to 108 cfu of C. jejuni 14N or C. jejuni 81–176 on the day of hatch and levels of bacterial colonisation measured over a period of 2–3 weeks. We consistently observed a 10- to 100-fold difference between four inbred lines in the number of C. jejuni organisms present in the cloaca or in the caeca, with the greatest differences detected between line N, which carried relatively high bacterial levels, and line 61, which carried relatively low numbers of bacteria. Amongst the four lines studied, major histocompatibility complex did not appear to be a major factor in determining the resistance. The difference in numbers of cloacal bacteria was observed as soon as 24 h after challenge and was still present at the end of the experiment. Lines N and 61 were chosen to analyse the mode of inheritance of the genetic differences in response to this infection. Challenge of progeny from reciprocal (N×61) and (61×N) F1 crosses and from (N×61) F1×N backcrosses with C. jejuni 14N revealed that the difference in bacterial numbers was inherited in a manner consistent with the resistance (low bacterial numbers) controlled by a single autosomal dominant locus. These data suggest that it might be possible to identify the genes responsible by genetic mapping and candidate gene analysis. 相似文献
23.
Burgess KL Corbett MS Eugenio P Lajkiewicz NJ Liu X Sanyal A Yan W Yuan Q Snyder JK 《Bioorganic & medicinal chemistry》2005,13(17):5299-5309
The development of chiral anthracene templates for use in Diels-Alder/retro Diels-Alder sequences is described. A summary of past results and new progress is reported. 相似文献
24.
Neurotrophins: a ticket to ride for BDNF 总被引:4,自引:0,他引:4
The secretion of BDNF from neurons is under activity-dependent control: this is crucial for the formation of appropriate synaptic connections during development and for learning and memory in adults. New evidence shows that interaction between a motif in the tertiary structure of BDNF and the sorting receptor carboxypeptidase E directs this neurotrophin to the regulated secretory pathway. 相似文献
25.
26.
Wenbiao Hu Kerrie Mengersen Shiu-Yun Fu Shilu Tong 《International journal of biometeorology》2010,54(4):433-440
This research assesses the potential impact of weekly weather variability on the incidence of cryptosporidiosis disease using
time series zero-inflated Poisson (ZIP) and classification and regression tree (CART) models. Data on weather variables, notified
cryptosporidiosis cases and population size in Brisbane were supplied by the Australian Bureau of Meteorology, Queensland
Department of Health, and Australian Bureau of Statistics, respectively. Both time series ZIP and CART models show a clear
association between weather variables (maximum temperature, relative humidity, rainfall and wind speed) and cryptosporidiosis
disease. The time series CART models indicated that, when weekly maximum temperature exceeded 31°C and relative humidity was
less than 63%, the relative risk of cryptosporidiosis rose by 13.64 (expected morbidity: 39.4; 95% confidence interval: 30.9–47.9).
These findings may have applications as a decision support tool in planning disease control and risk-management programs for
cryptosporidiosis disease. 相似文献
27.
Yu W Mengersen K Wang X Ye X Guo Y Pan X Tong S 《International journal of biometeorology》2012,56(4):569-581
The impact of climate change on the health of vulnerable groups such as the elderly has been of increasing concern. However, to date there has been no meta-analysis of current literature relating to the effects of temperature fluctuations upon mortality amongst the elderly. We synthesised risk estimates of the overall impact of daily mean temperature on elderly mortality across different continents. A comprehensive literature search was conducted using MEDLINE and PubMed to identify papers published up to December 2010. Selection criteria including suitable temperature indicators, endpoints, study-designs and identification of threshold were used. A two-stage Bayesian hierarchical model was performed to summarise the percent increase in mortality with a 1°C temperature increase (or decrease) with 95% confidence intervals in hot (or cold) days, with lagged effects also measured. Fifteen studies met the eligibility criteria and almost 13 million elderly deaths were included in this meta-analysis. In total, there was a 2-5% increase for a 1°C increment during hot temperature intervals, and a 1-2 % increase in all-cause mortality for a 1°C decrease during cold temperature intervals. Lags of up to 9 days in exposure to cold temperature intervals were substantially associated with all-cause mortality, but no substantial lagged effects were observed for hot intervals. Thus, both hot and cold temperatures substantially increased mortality among the elderly, but the magnitude of heat-related effects seemed to be larger than that of cold effects within a global context. 相似文献
28.
Edwards D Wilcox S Barrero RA Fleury D Cavanagh CR Forrest KL Hayden MJ Moolhuijzen P Keeble-Gagnère G Bellgard MI Lorenc MT Shang CA Baumann U Taylor JM Morell MK Langridge P Appels R Fitzgerald A 《Plant biotechnology journal》2012,10(6):703-708
The large and complex genome of wheat makes genetic and genomic analysis in this important species both expensive and resource intensive. The application of next-generation sequencing technologies is particularly resource intensive, with at least 17?Gbp of sequence data required to obtain minimal (1×) coverage of the genome. A similar volume of data would represent almost 40× coverage of the rice genome. Progress can be made through the establishment of consortia to produce shared genomic resources. Australian wheat genome researchers, working with Bioplatforms Australia, have collaborated in a national initiative to establish a genetic diversity dataset representing Australian wheat germplasm based on whole genome next-generation sequencing data. Here, we describe the establishment and validation of this resource which can provide a model for broader international initiatives for the analysis of large and complex genomes. 相似文献
29.
A multiparent advanced generation inter-cross population for genetic analysis in wheat 总被引:1,自引:0,他引:1
Huang BE George AW Forrest KL Kilian A Hayden MJ Morell MK Cavanagh CR 《Plant biotechnology journal》2012,10(7):826-839
We present the first results from a novel multiparent advanced generation inter-cross (MAGIC) population derived from four elite wheat cultivars. The large size of this MAGIC population (1579 progeny), its diverse genetic composition and high levels of recombination all contribute to its value as a genetic resource. Applications of this resource include interrogation of the wheat genome and the analysis of gene-trait association in agronomically important wheat phenotypes. Here, we report the utilization of a MAGIC population for the first time for linkage map construction. We have constructed a linkage map with 1162 DArT, single nucleotide polymorphism and simple sequence repeat markers distributed across all 21 chromosomes. We benchmark this map against a high-density DArT consensus map created by integrating more than 100 biparental populations. The linkage map forms the basis for further exploration of the genetic architecture within the population, including characterization of linkage disequilibrium, founder contribution and inclusion of an alien introgression into the genetic map. Finally, we demonstrate the application of the resource for quantitative trait loci mapping using the complex traits plant height and hectolitre weight as a proof of principle. 相似文献
30.
Robin A. Ohm Nicolas Feau Bernard Henrissat Conrad L. Schoch Benjamin A. Horwitz Kerrie W. Barry Bradford J. Condon Alex C. Copeland Braham Dhillon Fabian Glaser Cedar N. Hesse Idit Kosti Kurt LaButti Erika A. Lindquist Susan Lucas Asaf A. Salamov Rosie E. Bradshaw Lynda Ciuffetti Richard C. Hamelin Gert H. J. Kema Christopher Lawrence James A. Scott Joseph W. Spatafora B. Gillian Turgeon Pierre J. G. M. de Wit Shaobin Zhong Stephen B. Goodwin Igor V. Grigoriev 《PLoS pathogens》2012,8(12)
The class Dothideomycetes is one of the largest groups of fungi with a high level of ecological diversity including many plant pathogens infecting a broad range of hosts. Here, we compare genome features of 18 members of this class, including 6 necrotrophs, 9 (hemi)biotrophs and 3 saprotrophs, to analyze genome structure, evolution, and the diverse strategies of pathogenesis. The Dothideomycetes most likely evolved from a common ancestor more than 280 million years ago. The 18 genome sequences differ dramatically in size due to variation in repetitive content, but show much less variation in number of (core) genes. Gene order appears to have been rearranged mostly within chromosomal boundaries by multiple inversions, in extant genomes frequently demarcated by adjacent simple repeats. Several Dothideomycetes contain one or more gene-poor, transposable element (TE)-rich putatively dispensable chromosomes of unknown function. The 18 Dothideomycetes offer an extensive catalogue of genes involved in cellulose degradation, proteolysis, secondary metabolism, and cysteine-rich small secreted proteins. Ancestors of the two major orders of plant pathogens in the Dothideomycetes, the Capnodiales and Pleosporales, may have had different modes of pathogenesis, with the former having fewer of these genes than the latter. Many of these genes are enriched in proximity to transposable elements, suggesting faster evolution because of the effects of repeat induced point (RIP) mutations. A syntenic block of genes, including oxidoreductases, is conserved in most Dothideomycetes and upregulated during infection in L. maculans, suggesting a possible function in response to oxidative stress. 相似文献