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71.
Gabriel S. Yapuncich Justin T. Gladman Doug M. Boyer 《American journal of physical anthropology》2015,157(3):472-506
Objective: Multiple meaningful ecological characterizations of a species revolve around body mass. Because body mass cannot be directly measured in extinct taxa, reliable body mass predictors are needed. Many published body mass prediction equations rely on dental dimensions, but certain skeletal dimensions may have a more direct and consistent relationship with body mass. We seek to evaluate the reliability of prediction equations for inferring euarchontan body mass based on measurements of the articular facet areas of the astragalus and calcaneus. Methods: Surface areas of five astragalar facets (n = 217 specimens) and two calcaneal facets (n = 163) were measured. Separate ordinary least squares and multiple regression equations are presented for different levels of taxonomic inclusivity, and the reliability of each equation is evaluated with the coefficient of determination, standard error of the estimate, mean prediction error, and the prediction sum of squares statistic. We compare prediction errors to published prediction equations that utilize dental and/or tarsal measures. Finally, we examine the effects of taxonomically specific regressions and apply our equations to a diverse set of non‐primates. Results: Our results reveal that predictions based on facet areas are more reliable than most linear dental or tarsal predictors. Multivariate approaches are often better than univariate methods, but require more information (making them less useful for fragmentary fossils). While some taxonomically specific regressions improve predictive ability, this is not true for all primate groups. Conclusions: Among individual facets, the ectal and fibular facets of the astragalus and the calcaneal cuboid facet are the best body mass predictors. Since these facets have primarily concave curvature and scale with positive allometry relative to body mass, it appears that candidate skeletal proxies for body mass can be identified based on their curvature and scaling coefficients. Am J Phys Anthropol 157:472–506, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
72.
Christina Greenaway Amelia Sandoe Bilkis Vissandjee Ian Kitai Doug Gruner Wendy Wobeser Kevin Pottie Erin Ueffing Dick Menzies Kevin Schwartzman 《CMAJ》2011,183(12):E939-E951
Background:
The foreign-born population bears a disproportionate health burden from tuberculosis, with a rate of active tuberculosis 20 times that of the non-Aboriginal Canadian-born population, and could therefore benefit from tuberculosis screening programs. We reviewed evidence to determine the burden of tuberculosis in immigrant populations, to assess the effectiveness of screening and treatment programs for latent tuberculosis infection, and to identify potential interventions to improve effectiveness.Methods:
We performed a systematic search for evidence of the burden of tuberculosis in immigrant populations and the benefits and harms, applicability, clinical considerations, and implementation issues of screening and treatment programs for latent tuberculosis infection in the general and immigrant populations. The quality of this evidence was assessed and ranked using the GRADE approach (Grading of Recommendations Assessment, Development and Evaluation).Results:
Chemoprophylaxis with isoniazid is highly efficacious in decreasing the development of active tuberculosis in people with latent tuberculosis infection who adhere to treatment. Monitoring for hepatotoxicity is required at all ages, but close monitoring is required in those 50 years of age and older. Adherence to screening and treatment for latent tuberculosis infection is poor, but it can be increased if care is delivered in a culturally sensitive manner.Interpretation:
Immigrant populations have high rates of active tuberculosis that could be decreased by screening for and treating latent tuberculosis infection. Several patient, provider and infrastructure barriers, poor diagnostic tests, and the long treatment course, however, limit effectiveness of current programs. Novel approaches that educate and engage patients, their communities and primary care practitioners might improve the effectiveness of these programs. 相似文献73.
Functional responses and scaling in predator-prey interactions of marine fishes: contemporary issues and emerging concepts 总被引:3,自引:0,他引:3
Hunsicker ME Ciannelli L Bailey KM Buckel JA Wilson White J Link JS Essington TE Gaichas S Anderson TW Brodeur RD Chan KS Chen K Englund G Frank KT Freitas V Hixon MA Hurst T Johnson DW Kitchell JF Reese D Rose GA Sjodin H Sydeman WJ van der Veer HW Vollset K Zador S 《Ecology letters》2011,14(12):1288-1299
Predator-prey interactions are a primary structuring force vital to the resilience of marine communities and sustainability of the world's oceans. Human influences on marine ecosystems mediate changes in species interactions. This generality is evinced by the cascading effects of overharvesting top predators on the structure and function of marine ecosystems. It follows that ecological forecasting, ecosystem management, and marine spatial planning require a better understanding of food web relationships. Characterising and scaling predator-prey interactions for use in tactical and strategic tools (i.e. multi-species management and ecosystem models) are paramount in this effort. Here, we explore what issues are involved and must be considered to advance the use of predator-prey theory in the context of marine fisheries science. We address pertinent contemporary ecological issues including (1) the approaches and complexities of evaluating predator responses in marine systems; (2) the 'scaling up' of predator-prey interactions to the population, community, and ecosystem level; (3) the role of predator-prey theory in contemporary fisheries and ecosystem modelling approaches; and (4) directions for the future. Our intent is to point out needed research directions that will improve our understanding of predator-prey interactions in the context of the sustainable marine fisheries and ecosystem management. 相似文献
74.
Shi Y Chan DW Jung SY Malovannaya A Wang Y Qin J 《Molecular & cellular proteomics : MCP》2011,10(5):M110.002089
Lysine ubiquitination is an important and versatile protein post-translational modification. Numerous cellular functions are regulated by ubiquitination, suggesting that extensive numbers of proteins, if not all, are modified with ubiquitin at certain times. However, proteome-wide profiling of ubiquitination sites in the mammalian system is technically challenging. We report the design and characterization of an engineered protein affinity reagent for the isolation of ubiquitinated proteins and the identification of ubiquitination sites with mass spectrometry. This recombinant protein consists of four tandem repeats of ubiquitin-associated domain from UBQLN1 fused to a GST tag. We used this GST-qUBA reagent to isolate polyubiquitinated proteins and identified 294 endogenous ubiquitination sites on 223 proteins from human 293T cells without proteasome inhibitors or overexpression of ubiquitin. Mitochondrial proteins constitute 14.7% of this data set, implicating ubiquitination in a wide range of mitochondrial functions. 相似文献
75.
Paul Peake James Fitzsimons Doug Frood Mel Mitchell Naomi Withers Matt White Rick Webster 《Ecological Management & Restoration》2011,12(2):128-137
Summary Large overbank flood events play an important role in maintaining large‐scale ecological processes and connectivity along and across the floodplains and between the rivers and their floodplains in the southern Murray‐Darling Basin. However, the regulation of rivers means that extensive overbank flooding can only occur in the rare circumstance of extreme flood events. Recent environmental water allocations have focussed on the largest floodplain blocks (‘icon’ sites) and a small set of specific values (e.g. colonial nesting waterbirds), as well as on trialling fine‐scale manipulation of infrastructure (e.g. pumping) to water relatively small areas. There has been no comprehensive systematic assessment of the entire floodplain and its wider set of flood‐dependent natural assets (such as ecosystems and species; herein referred to as ‘natural values’) to maximise the effectiveness of environmental water use and to catalogue values likely to be lost. This paper describes an assessment of some 220 000 ha found to support flood‐dependent natural values in Victoria. We mapped the geographic distribution and estimated components of the flooding requirements (natural flooding frequency, and maximum period without flooding and minimum duration of each flooding event before significant deterioration) for each natural value. Using an example of one stretch of the River Murray, we show how the resultant spatial data can be used with floodplain inundation modelling to compare the outcomes of real or planned environmental watering events; potentially providing tools for management agencies to conserve a wider range of floodplain values than is currently the case. That is, water managers and the public can see what ecosystems and threatened species are intended to be maintained by environmental watering and what values are intended to be abandoned across the whole floodplain, rather than just seeing the small subset of values and ‘icon’ sites that are intended to be maintained. Examples are provided to illustrate how information about the location, water requirements and extent covered by potential floods for specific values can be used to build adaptive watering strategies for areas as large as the whole floodplain. 相似文献
76.
A global reorganization of the metabolome in Arabidopsis during cold acclimation is revealed by metabolic fingerprinting 总被引:3,自引:1,他引:2
Many plants, including Arabidopsis , increase their freezing tolerance in response to low, non-freezing temperatures. This process is known as cold acclimation and involves many complex biochemical changes at the level of the metabolome. Our goal was to examine the effects of cold acclimation on the metabolome using a non-targeted metabolic fingerprinting approach. Multivariate data analyses indicate that, in Arabidopsis, a global reprogramming of metabolism occurs as a result of cold acclimation. By measuring an entire spectrum of putative metabolites based on mass-to-charge ( m / z ) ratios, vs. an individual or group of metabolite(s), a comprehensive, unbiased assessment of metabolic processes relative to cold acclimation was determined. Whereas leaves shifted to low temperature present metabolic profiles that are constantly changing, leaves developed at low temperature demonstrate a stable complement of components. Although it appears that some metabolic networks are modulated by the environment, others require development under low-temperature conditions for adjustment. Understanding how metabolism as a whole is regulated allows the integration of cellular, physiological and ecological attributes in a biological system, a necessity if complex traits, such as freezing tolerance, are to be modified by breeding or genetic manipulation. 相似文献
77.
78.
Robarge MJ Bom DC Tumey LN Varga N Gleason E Silver D Song J Murphy SM Ekema G Doucette C Hanniford D Palmer M Pawlowski G Danzig J Loftus M Hunady K Sherf BA Mays RW Stricker-Krongrad A Brunden KR Harrington JJ Bennani YL 《Bioorganic & medicinal chemistry letters》2005,15(6):1749-1753
The chemoattractant receptor-homologous molecule expressed on T(H)2 cells (CRTH-2), also found on eosinophils and basophils, is a prostaglandin D2 receptor involved in the recruitment of these cell types during an inflammatory response. In this report, we describe the synthesis and optimization of a ramatroban isostere that is a selective and potent antagonist of CRTH-2 which may be useful in the treatment of certain diseases. 相似文献
79.
Golden TR Hubbard A Morten KJ Hinerfeld D Melov S 《Free radical biology & medicine》2005,39(2):152-163
The majority of cellular superoxide is generated in the mitochondria as a by-product of normal oxidative metabolism. In the mitochondria, superoxide is detoxified by manganese superoxide dismutase (SOD2). Mice lacking SOD2 demonstrate a multifaceted neonatal lethal phenotype, including a spongiform encephalopathy that is preventable through antioxidant treatment. The molecular events behind the observed pathology in the cortex of these mice are unknown. We hypothesized that the lack of SOD2 would result in significant changes in cortical gene expression and that therapeutically beneficial antioxidant treatment would normalize the expression of some genes, providing insight into the mechanism by which mitochondrial oxidative stress results in neurodegeneration. We report the identification of gene expression profiles associated with this paradigm, which characterize the degree of response to the pharmacologic intervention. We have identified specific pathways targeted by endogenous oxidative stress, including glutathione metabolism, iron metabolism, and cell-survival pathways centering on the kinase AKT. The normalization of expression of some of these pathways by antioxidant treatment suggests approaches to treating disease in which endogenous oxidative stress plays a role. 相似文献
80.
The Open Microscopy Environment (OME) Data Model and XML file: open tools for informatics and quantitative analysis in biological imaging 总被引:2,自引:0,他引:2
Goldberg IG Allan C Burel JM Creager D Falconi A Hochheiser H Johnston J Mellen J Sorger PK Swedlow JR 《Genome biology》2005,6(5):R47
The Open Microscopy Environment (OME) defines a data model and a software implementation to serve as an informatics framework for imaging in biological microscopy experiments, including representation of acquisition parameters, annotations and image analysis results. OME is designed to support high-content cell-based screening as well as traditional image analysis applications. The OME Data Model, expressed in Extensible Markup Language (XML) and realized in a traditional database, is both extensible and self-describing, allowing it to meet emerging imaging and analysis needs. 相似文献