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排序方式: 共有235条查询结果,搜索用时 15 毫秒
111.
Daniel Cross Jaime Ramos Barbara Mellers Philip E. Tetlock David W. Scott 《Journal of forecasting》2018,37(3):259-268
The Good Judgment Team led by psychologists P. Tetlock and B. Mellers of the University of Pennsylvania was the most successful of five research projects sponsored through 2015 by the Intelligence Advanced Research Projects Activity to develop improved group forecast aggregation algorithms. Each team had at least 10 algorithms under continuous development and evaluation over the 4‐year project. The mean Brier score was used to rank the algorithms on approximately 130 questions concerning categorical geopolitical events each year. An algorithm would return aggregate probabilities for each question based on the probabilities provided per question by thousands of individuals, who had been recruited by the Good Judgment Team. This paper summarizes the theorized basis and implementation of one of the two most accurate algorithms at the conclusion of the Good Judgment Project. The algorithm incorporated a number of pre‐ and postprocessing steps, and relied upon a minimum distance robust regression method called L2E. The algorithm was just edged out by a variation of logistic regression, which has been described elsewhere. Work since the official conclusion of the project has led to an even smaller gap. 相似文献
112.
Diets of the Common Screech Owl ( Otus asio ) and Burrowing Owl ( Athene cunicularia ) from the Great Basin, Malheur County, southeastern Oregon, were studied. Although there was considerable overlap in the diets of these owls, there were differences related to habitat use. 相似文献
113.
Christoph-Erik Mayer Barbara Haigl Florian Jantscher Gerald Siegwart Michael Grusch Walter Berger Hedwig Sutterlüty 《Cellular and molecular life sciences : CMLS》2010,67(19):3299-3311
Sprouty2 is an important inhibitor of cell proliferation and signal transduction. In this study, we found a bimodal expression
of Sprouty2 protein during cell cycle progression after exit from quiescence, whereas elevated Sprouty4 expression in the
G1 phase stayed high throughout the rest of the cell cycle. Induction of the mitogen-activated protein kinase via activated
Ras was crucial for increased Sprouty2 expression at the G0/G1 transition. Following the first peak, accelerated proteasomal
protein degradation caused a transient attenuation of Sprouty2 abundance during late G1. Since the decline in its expression
was abolished by dominant negative c-Cbl and the timely restricted interaction between Sprouty2 and c-Cbl disappeared at the
second peak of Sprouty2 expression, we conclude that the second phase in the cell cycle-specific expression profile of Sprouty2
is solely dependent on ubiquitination by c-Cbl. Our results suggest that Sprouty2 abundance is the result of strictly coordinated
activities of Ras and c-Cbl. 相似文献
114.
115.
The genus Stenogonum Nutt. (Polygonaceae) is reestablished and distinguished from Eriogonum Michx. with which it has been synonymized since 1853. The genus, as outlined here, differs from Eriogonum in having two whorls of three foliaceous bracts surrounding the flowers instead of the normal, united tubular involucre. Stenogonum contains two species, S. flexum and S. salsuginosum; they are restricted primarily to the Colorado Plateau of Wyoming southward through eastern Utah and western Colorado to northwestern New Mexico and adjacent northern Arizona. Both species are illustrated and their respective ranges mapped. 相似文献
116.
Benzinou M Creemers JW Choquet H Lobbens S Dina C Durand E Guerardel A Boutin P Jouret B Heude B Balkau B Tichet J Marre M Potoczna N Horber F Le Stunff C Czernichow S Sandbaek A Lauritzen T Borch-Johnsen K Andersen G Kiess W Körner A Kovacs P Jacobson P Carlsson LM Walley AJ Jørgensen T Hansen T Pedersen O Meyre D Froguel P 《Nature genetics》2008,40(8):943-945
Mutations in PCSK1 cause monogenic obesity. To assess the contribution of PCSK1 to polygenic obesity risk, we genotyped tag SNPs in a total of 13,659 individuals of European ancestry from eight independent case-control or family-based cohorts. The nonsynonymous variants rs6232, encoding N221D, and rs6234-rs6235, encoding the Q665E-S690T pair, were consistently associated with obesity in adults and children (P = 7.27 x 10(-8) and P = 2.31 x 10(-12), respectively). Functional analysis showed a significant impairment of the N221D-mutant PC1/3 protein catalytic activity. 相似文献
117.
Andre M Boustany Scott F Davis Peter Pyle Scot D Anderson Burney J Le Boeuf Barbara A Block 《Nature》2002,415(6867):35-36
Until the advent of electronic tagging technology, the inherent difficulty of studying swift and powerful marine animals made ecological information about sharks of the family Lamnidae difficult to obtain. Here we report the tracking of movements of white sharks by using pop-up satellite archival tags, which reveal that their migratory movements, depth and ambient thermal ranges are wider than was previously thought. 相似文献
118.
Morin RD Mendez-Lago M Mungall AJ Goya R Mungall KL Corbett RD Johnson NA Severson TM Chiu R Field M Jackman S Krzywinski M Scott DW Trinh DL Tamura-Wells J Li S Firme MR Rogic S Griffith M Chan S Yakovenko O Meyer IM Zhao EY Smailus D Moksa M Chittaranjan S Rimsza L Brooks-Wilson A Spinelli JJ Ben-Neriah S Meissner B Woolcock B Boyle M McDonald H Tam A Zhao Y Delaney A Zeng T Tse K Butterfield Y Birol I Holt R Schein J Horsman DE Moore R Jones SJ Connors JM Hirst M Gascoyne RD Marra MA 《Nature》2011,476(7360):298-303
Follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL) are the two most common non-Hodgkin lymphomas (NHLs). Here we sequenced tumour and matched normal DNA from 13 DLBCL cases and one FL case to identify genes with mutations in B-cell NHL. We analysed RNA-seq data from these and another 113 NHLs to identify genes with candidate mutations, and then re-sequenced tumour and matched normal DNA from these cases to confirm 109 genes with multiple somatic mutations. Genes with roles in histone modification were frequent targets of somatic mutation. For example, 32% of DLBCL and 89% of FL cases had somatic mutations in MLL2, which encodes a histone methyltransferase, and 11.4% and 13.4% of DLBCL and FL cases, respectively, had mutations in MEF2B, a calcium-regulated gene that cooperates with CREBBP and EP300 in acetylating histones. Our analysis suggests a previously unappreciated disruption of chromatin biology in lymphomagenesis. 相似文献
119.
120.
Collins PY Patel V Joestl SS March D Insel TR Daar AS;Scientific Advisory Board the Executive Committee of the Grand Challenges on Global Mental Health Anderson W Dhansay MA Phillips A Shurin S Walport M Ewart W Savill SJ Bordin IA Costello EJ Durkin M Fairburn C Glass RI Hall W Huang Y Hyman SE Jamison K Kaaya S Kapur S Kleinman A Ogunniyi A Otero-Ojeda A Poo MM Ravindranath V Sahakian BJ Saxena S Singer PA Stein DJ 《Nature》2011,475(7354):27-30