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排序方式: 共有105条查询结果,搜索用时 15 毫秒
31.
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Stolk L Perry JR Chasman DI He C Mangino M Sulem P Barbalic M Broer L Byrne EM Ernst F Esko T Franceschini N Gudbjartsson DF Hottenga JJ Kraft P McArdle PF Porcu E Shin SY Smith AV van Wingerden S Zhai G Zhuang WV Albrecht E Alizadeh BZ Aspelund T Bandinelli S Lauc LB Beckmann JS Boban M Boerwinkle E Broekmans FJ Burri A Campbell H Chanock SJ Chen C Cornelis MC Corre T Coviello AD d'Adamo P Davies G de Faire U de Geus EJ Deary IJ Dedoussis GV Deloukas P Ebrahim S Eiriksdottir G Emilsson V 《Nature genetics》2012,44(3):260-268
To newly identify loci for age at natural menopause, we carried out a meta-analysis of 22 genome-wide association studies (GWAS) in 38,968 women of European descent, with replication in up to 14,435 women. In addition to four known loci, we identified 13 loci newly associated with age at natural menopause (at P < 5 × 10(-8)). Candidate genes located at these newly associated loci include genes implicated in DNA repair (EXO1, HELQ, UIMC1, FAM175A, FANCI, TLK1, POLG and PRIM1) and immune function (IL11, NLRP11 and PRRC2A (also known as BAT2)). Gene-set enrichment pathway analyses using the full GWAS data set identified exoDNase, NF-κB signaling and mitochondrial dysfunction as biological processes related to timing of menopause. 相似文献
33.
COURSE TIMETABLING AT A TUNISIAN UNIVERSITY: A CASE STUDY 总被引:2,自引:0,他引:2
Abdelaziz DAMMAK Abdelkarim ELLOUMI Hichem KAMOUN Jacques A.FERLAND 《系统科学与系统工程学报(英文版)》2008,17(3):334-352
This paper deals with the Course Timetabling Problem at an institution in a Tunisian University. We introduce a heuristic procedure to construct a feasible timetable for all lectures and tutorials taken by different groups of each sub-section of any section. We describe the timetabling problem using a list of all specific hard and soft constraints. We formulate the problem as a set of linear constraints using two sets of binary variables corresponding to lectures and tutorials, respectively. This heuristic is illustrated with real data for a sub-section of the Faculty of Economics and Management Sciences of Sfax in Tunisia, and the resulting timetables are compared with those generated manually. The results of another full section have confirmed the good quality of the proposed heuristic when compared with the hand made solution. 相似文献
34.
Genome-wide association defines more than 30 distinct susceptibility loci for Crohn's disease 总被引:2,自引:0,他引:2
Barrett JC Hansoul S Nicolae DL Cho JH Duerr RH Rioux JD Brant SR Silverberg MS Taylor KD Barmada MM Bitton A Dassopoulos T Datta LW Green T Griffiths AM Kistner EO Murtha MT Regueiro MD Rotter JI Schumm LP Steinhart AH Targan SR Xavier RJ;NIDDK IBD Genetics Consortium Libioulle C Sandor C Lathrop M Belaiche J Dewit O Gut I Heath S Laukens D Mni M Rutgeerts P Van Gossum A Zelenika D Franchimont D Hugot JP de Vos M Vermeire S 《Nature genetics》2008,40(8):955-962
Several risk factors for Crohn's disease have been identified in recent genome-wide association studies. To advance gene discovery further, we combined data from three studies on Crohn's disease (a total of 3,230 cases and 4,829 controls) and carried out replication in 3,664 independent cases with a mixture of population-based and family-based controls. The results strongly confirm 11 previously reported loci and provide genome-wide significant evidence for 21 additional loci, including the regions containing STAT3, JAK2, ICOSLG, CDKAL1 and ITLN1. The expanded molecular understanding of the basis of this disease offers promise for informed therapeutic development. 相似文献
35.
Jacques Dutka 《Archive for History of Exact Sciences》1991,43(3):225-249
Communicated by U. Bottazzini 相似文献
36.
The rapid closure of the Venus flytrap (Dionaea muscipula) leaf in about 100 ms is one of the fastest movements in the plant kingdom. This led Darwin to describe the plant as "one of the most wonderful in the world". The trap closure is initiated by the mechanical stimulation of trigger hairs. Previous studies have focused on the biochemical response of the trigger hairs to stimuli and quantified the propagation of action potentials in the leaves. Here we complement these studies by considering the post-stimulation mechanical aspects of Venus flytrap closure. Using high-speed video imaging, non-invasive microscopy techniques and a simple theoretical model, we show that the fast closure of the trap results from a snap-buckling instability, the onset of which is controlled actively by the plant. Our study identifies an ingenious solution to scaling up movements in non-muscular engines and provides a general framework for understanding nastic motion in plants. 相似文献
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Jacques Dutka 《Archive for History of Exact Sciences》1981,24(1):11-29
Summary A history of the development of the incomplete beta function is outlined as well as of some of the analytical and approximation techniques used for its numerical evaluation.
Dedicated to W. Edwards Deming, my teacher and my friend 相似文献
39.
Hartogh P Lis DC Bockelée-Morvan D de Val-Borro M Biver N Küppers M Emprechtinger M Bergin EA Crovisier J Rengel M Moreno R Szutowicz S Blake GA 《Nature》2011,478(7368):218-220
For decades, the source of Earth's volatiles, especially water with a deuterium-to-hydrogen ratio (D/H) of (1.558?±?0.001)?×?10(-4), has been a subject of debate. The similarity of Earth's bulk composition to that of meteorites known as enstatite chondrites suggests a dry proto-Earth with subsequent delivery of volatiles by local accretion or impacts of asteroids or comets. Previous measurements in six comets from the Oort cloud yielded a mean D/H ratio of (2.96?±?0.25)?×?10(-4). The D/H value in carbonaceous chondrites, (1.4?±?0.1)?×?10(-4), together with dynamical simulations, led to models in which asteroids were the main source of Earth's water, with ≤10 per cent being delivered by comets. Here we report that the D/H ratio in the Jupiter-family comet 103P/Hartley 2, which originated in the Kuiper belt, is (1.61?±?0.24)?×?10(-4). This result substantially expands the reservoir of Earth ocean-like water to include some comets, and is consistent with the emerging picture of a complex dynamical evolution of the early Solar System. 相似文献
40.