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排序方式: 共有638条查询结果,搜索用时 15 毫秒
11.
Greg Clark Josh Russell Peter Enyeart Brant Gracia Aimee Wessel Inga Jarmoskaite Damon Polioudakis Yoel Stuart Tony Gonzalez Al MacKrell Stacia Rodenbusch Gwendolyn M. Stovall Josh T. Beckham Michael Montgomery Tania Tasneem Jack Jones Sarah Simmons Stanley Roux 《PLoS biology》2016,14(2)
Both scientists and the public would benefit from improved communication of basic scientific research and from integrating scientists into education outreach, but opportunities to support these efforts are limited. We have developed two low-cost programs—"Present Your PhD Thesis to a 12-Year-Old" and "Shadow a Scientist”—that combine training in science communication with outreach to area middle schools. We assessed the outcomes of these programs and found a 2-fold benefit: scientists improve their communication skills by explaining basic science research to a general audience, and students'' enthusiasm for science and their scientific knowledge are increased. Here we present details about both programs, along with our assessment of them, and discuss the feasibility of exporting these programs to other universities. 相似文献
12.
Social carry‐over effects underpin trans‐seasonally linked structure in a wild bird population
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Spatial structure underpins numerous population processes by determining the environment individuals' experience and which other individuals they encounter. Yet, how the social landscape influences individuals' spatial decisions remains largely unexplored. Wild great tits (Parus major) form freely moving winter flocks, but choose a single location to establish a breeding territory over the spring. We demonstrate that individuals' winter social associations carry‐over into their subsequent spatial decisions, as individuals breed nearer to those they were most associated with during winter. Further, they also form territory boundaries with their closest winter associates, irrespective of breeding distance. These findings were consistent across years, and among all demographic classes, suggesting that such social carry‐over effects may be general. Thus, prior social structure can shape the spatial proximity, and fine‐scale arrangement, of breeding individuals. In this way, social networks can influence a wide range of processes linked to individuals' breeding locations, including other social interactions themselves. 相似文献
13.
Kentaro Ohkuni Yoshimitsu Takahashi Alyona Fulp Josh Lawrimore Wei-Chun Au Nagesh Pasupala Reuben Levy-Myers Jack Warren Alexander Strunnikov Richard E. Baker Oliver Kerscher Kerry Bloom Munira A. Basrai 《Molecular biology of the cell》2016,27(9):1500-1510
Centromeric histone H3, CENP-ACse4, is essential for faithful chromosome segregation. Stringent regulation of cellular levels of CENP-ACse4 restricts its localization to centromeres. Mislocalization of CENP-ACse4 is associated with aneuploidy in yeast and flies and tumorigenesis in human cells; thus defining pathways that regulate CENP-A levels is critical for understanding how mislocalization of CENP-A contributes to aneuploidy in human cancers. Previous work in budding yeast shows that ubiquitination of overexpressed Cse4 by Psh1, an E3 ligase, partially contributes to proteolysis of Cse4. Here we provide the first evidence that Cse4 is sumoylated by E3 ligases Siz1 and Siz2 in vivo and in vitro. Ubiquitination of Cse4 by the small ubiquitin-related modifier (SUMO)-targeted ubiquitin ligase (STUbL) Slx5 plays a critical role in proteolysis of Cse4 and prevents mislocalization of Cse4 to euchromatin under normal physiological conditions. Accumulation of sumoylated Cse4 species and increased stability of Cse4 in slx5∆ strains suggest that sumoylation precedes ubiquitin-mediated proteolysis of Cse4. Slx5-mediated Cse4 proteolysis is independent of Psh1, since slx5∆ psh1∆ strains exhibit higher levels of Cse4 stability and mislocalization than either slx5∆ or psh1∆ strains. Our results demonstrate a role for Slx5 in ubiquitin-mediated proteolysis of Cse4 to prevent its mislocalization and maintain genome stability. 相似文献
14.
Elizabeth M. Phillips John K. Horne Jeannette E. Zamon Jonathan J. Felis Josh Adams 《Ecology and evolution》2019,9(8):4805-4819
Studies estimating species' distributions require information about animal locations in space and time. Location data can be collected using surveys within a predetermined frame of reference (i.e., Eulerian sampling) or from animal‐borne tracking devices (i.e., Lagrangian sampling). Integration of observations obtained from Eulerian and Lagrangian perspectives can provide insights into animal movement and habitat use. However, contemporaneous data from both perspectives are rarely available, making examination of biases associated with each sampling approach difficult. We compared distributions of a mobile seabird observed concurrently from ship, aerial, and satellite tag surveys during May, June, and July 2012 in the northern California Current. We calculated utilization distributions to quantify and compare variability in common murre (Uria aalge) space use and examine how sampling perspective and platform influence observed patterns. Spatial distributions of murres were similar in May, regardless of sampling perspective. Greatest densities occurred in coastal waters off southern Washington and northern Oregon, near large murre colonies and the mouth of the Columbia River. Density distributions of murres estimated from ship and aerial surveys in June and July were similar to those observed in May, whereas distributions of satellite‐tagged murres in June and July indicated northward movement into British Columbia, Canada, resulting in different patterns observed from Eulerian and Lagrangian perspectives. These results suggest that the population of murres observed in the northern California Current during spring and summer includes relatively stationary individuals attending breeding colonies and nonstationary, vagile adults and subadults. Given the expected growth of telemetry studies and advances in survey technology (e.g., unmanned aerial systems), these results highlight the importance of considering methodological approaches, spatial extent, and synopticity of distribution data sets prior to integrating data from different sampling perspectives. 相似文献
15.
Snodgrass JJ Leonard WR Tarskaia LA McDade TW Sorensen MV Alekseev VP Krivoshapkin VG 《Journal of physiological anthropology》2007,26(2):241-246
C-reactive protein (CRP) is an inflammatory marker, which at low-level elevations is associated with increased cardiovascular risk. Although CRP has been extensively investigated in North American and European settings, few studies have measured CRP among non-Western groups. The present study used dried whole blood spot samples to examine high-sensitivity CRP concentrations among the Yakut (Sakha) of Siberia (85 females, 56 males; 18-58 years old). Our goals were: (1) to compare Yakut CRP concentrations with other populations; (2) to investigate sex differences; and (3) to explore anthropometric correlates of CRP. Results indicate that serum equivalent CRP concentrations are similar to those from industrializing nations, lower than US and European values, and greater than Japanese concentrations. Yakut men and women display similar CRP concentrations; however, CRP was significantly higher among men after adjustment for body fat, age, and smoking. Positive associations were documented between CRP and BMI, body fat, and central adiposity. 相似文献
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17.
Single-cell paradigms have greatly expanded our knowledge about stimulus-secretion coupling, but the understanding of stimulus-gene expression coupling has lagged behind for lack of a dynamic model sufficiently sensitive to provide single-cell resolution. In the present study, we made continuous indirect measurements within individual, living cells of expression dynamics both before and after treatment with a gene-activating secretagogue. This was accomplished by transfecting (via microinjection) individual, primary mammotropes with a PRL promoter-driven luciferase reporter plasmid, and then quantifying the rate of photonic emissions (reflective of endogenous gene activity). We found that individual cells exhibit spontaneous, random, short-term fluctuations of basal reporter activity and are extremely heterogeneous in terms of responses to a stimulatory agent (TRH). In addition, we found that responses are affected by several factors including the secretory status of the pituitary donor, the manner in which the stimulus is presented, and by the initial level of reporter activity. Moreover, the responsiveness of an individual cell can fluctuate dramatically over time. These results invite speculation that a given cell can "sense" its gene activation state and regulate its response accordingly to satisfy requirements for the corresponding secretory product. 相似文献
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19.
Josh?Marko Colin?L.?SoskolneEmail author John?Church Louis?H.?Francescutti Mark?Anielski 《EcoHealth》2004,1(4):374-386
To adequately analyze the impacts associated with the rising use of automobiles, an assessment framework is needed that includes environment, health, economic, and sociocultural impacts. Such a framework was developed and applied to a proposed freeway-widening project in Edmonton, Canada. The assessment framework was developed using both Multi-Criteria Analysis and the Ecosystem Approach to Human Health (Ecohealth). Community participation was vital in the application of the assessment framework to this case study. Six stakeholder groups, including community members, City Councillors, and health, environment, and transportation experts, provided needed qualitative data for the assessment framework. Quantitative data were gathered from an ecological study design that associated traffic volumes with respiratory conditions in Edmonton. Community members perceptions about the impacts of the freeway widening differed from those of the expert groups in a number of areas. Environmental and health degradation was more of an issue to community members than to expert groups. Though respiratory conditions were not projected to increase by a significant amount because of the freeway widening, further analysis is necessary on other biophysical and socioeconomic impacts listed in the assessment framework. The divergence in opinion between community members and experts suggests that more communication is needed between these groups in relation to transportation planning. The Ecohealth approach ensures that community concerns are addressed in transportation planning. 相似文献
20.
Novel chimeric immunomodulatory compounds containing short CpG oligodeoxyribonucleotides have differential activities in human cells 总被引:1,自引:0,他引:1
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Marshall JD Hessel EM Gregorio J Abbate C Yee P Chu M Van Nest G Coffman RL Fearon KL 《Nucleic acids research》2003,31(17):5122-5133
Immunostimulatory DNA sequences (ISS) containing CpG motifs induce interferon-α (IFN-α) and interferon-γ (IFN-γ) from human peripheral blood mononuclear cells and stimulate human B cells to proliferate and produce IL-6. We studied the motif and structural requirements for both types of activity using novel chimeric immunomodulatory compounds (CICs), which contain multiple heptameric ISS connected by non-nucleoside spacers in both linear and branched configurations. We found that the optimal motifs and structure for IFN-α production versus B cell activation differed. IFN-α production was optimal for CICs containing the sequences 5′-TCGXCGX and 5′-TCGXTCG, where X is any nucleotide. The presentation of multiple copies of these heptameric ISS with free 5′-ends via long, hydrophilic spacers, such as hexaethylene glycol, significantly enhanced the induction of IFN-α. Conversely, human B cell activity was predominately dependent on ISS motif, with 5′-TCGTXXX and 5′-AACGTTC being the most active sequences. Thus, we found CICs could be ‘programmed’ for IFN-α production or B cell activation as independent variables. Additionally, CICs with separate human- and mouse-specific motifs were synthesized and these were used to confirm in vivo activity in mice. CICs may offer unique advantages over conventional ISS because identification of the optimal motifs, spacers and structures for different biological properties allows for the assembly of CICs exhibiting a defined set of activities tailored for specific clinical applications. 相似文献