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11.
The article presents an overview of trends in cohabitation and marriage in Britain over several decades, using a consistent set of retrospective histories from the General Household Survey 1979-2007. Time-trends are presented, for men and women, of: the experience of different types of partnership by specified ages, the frequency of premarital cohabitation, the average time spent in different types of partnership, the timing of life course transitions, and the outcome of cohabitation and marriage at the fifth and tenth anniversaries. 相似文献
12.
Two unusual types of behaviour (wandering and intraspecific aggressive behaviour) have been observed when rearing larvae of two species of the tribe Hyperini. Wandering of Hypera postica in search for food was observed in L1, L2 and L3 larvae, as well as in young L4 larvae. L1 larvae also disperse in response to crowding. Wandering of L2 to young L4 instars was a response to food shortage. Wandering of late L4 larva (‘prepupa’) occurs because of searching for a place to spin the cocoon and pupate. Encounters between the larvae may result in agonistic behaviour, and some larvae may die as a consequence of fighting. This aggression increases with food limitation. Agonistic intraspecific behaviour has not been described to date in weevil’s larvae and it probably may not occur under natural conditions when there is a plenty of food and larval densities are decreased by pathogens or parasitoids. 相似文献
13.
Quesada V Conde L Villamor N Ordóñez GR Jares P Bassaganyas L Ramsay AJ Beà S Pinyol M Martínez-Trillos A López-Guerra M Colomer D Navarro A Baumann T Aymerich M Rozman M Delgado J Giné E Hernández JM González-Díaz M Puente DA Velasco G Freije JM Tubío JM Royo R Gelpí JL Orozco M Pisano DG Zamora J Vázquez M Valencia A Himmelbauer H Bayés M Heath S Gut M Gut I Estivill X López-Guillermo A Puente XS Campo E López-Otín C 《Nature genetics》2012,44(1):47-52
Here we perform whole-exome sequencing of samples from 105 individuals with chronic lymphocytic leukemia (CLL), the most frequent leukemia in adults in Western countries. We found 1,246 somatic mutations potentially affecting gene function and identified 78 genes with predicted functional alterations in more than one tumor sample. Among these genes, SF3B1, encoding a subunit of the spliceosomal U2 small nuclear ribonucleoprotein (snRNP), is somatically mutated in 9.7% of affected individuals. Further analysis in 279 individuals with CLL showed that SF3B1 mutations were associated with faster disease progression and poor overall survival. This work provides the first comprehensive catalog of somatic mutations in CLL with relevant clinical correlates and defines a large set of new genes that may drive the development of this common form of leukemia. The results reinforce the idea that targeting several well-known genetic pathways, including mRNA splicing, could be useful in the treatment of CLL and other malignancies. 相似文献
14.
Agustí Nieto-Galan 《Annals of science》2013,70(4):497-528
Scrutinizing the main activities of the Sociedad Astronómica de Barcelona (SAB), a scientific society that was founded in 1910 and lasted until 1921, this paper analyses how and why its members disseminated astronomy to society at large. Inspired by Camille Flammarion (1842–1925), and with a strong amateur character, the programme of the SAB raised interest among academic scientists, politicians, priests, navy officers, educated audiences, and positivist anticlerical writers. It rapidly conquered the public sphere through well-attended lectures, exhibitions, observations, and publications. In the context of an industrial city, which at that time was suffering serious social tensions, the popularization of astronomy transcended social and cultural boundaries. It created common ground between expert and lay knowledge, science and art, the ‘natural’ and the ‘social’, and between science and religion. In addition, it was considered as one of the only possible ways to raise the scientific level of a country such as Spain, which at that time perceived itself as peripheral, even backward, in terms of mainstream innovations in science and technology. 相似文献
15.
Norman PJ Abi-Rached L Gendzekhadze K Korbel D Gleimer M Rowley D Bruno D Carrington CV Chandanayingyong D Chang YH Crespí C Saruhan-Direskeneli G Fraser PA Hameed K Kamkamidze G Koram KA Layrisse Z Matamoros N Milà J Park MH Pitchappan RM Ramdath DD Shiau MY Stephens HA Struik S Verity DH Vaughan RW Tyan D Davis RW Riley EM Ronaghi M Parham P 《Nature genetics》2007,39(9):1092-1099
Interactions of killer cell immunoglobulin-like receptors (KIRs) with major histocompatibility complex (MHC) class I ligands diversify natural killer cell responses to infection. By analyzing sequence variation in diverse human populations, we show that the KIR3DL1/S1 locus encodes two lineages of polymorphic inhibitory KIR3DL1 allotypes that recognize Bw4 epitopes of protein">HLA-A and HLA-B and one lineage of conserved activating KIR3DS1 allotypes, also implicated in Bw4 recognition. Balancing selection has maintained these three lineages for over 3 million years. Variation was selected at D1 and D2 domain residues that contact HLA class I and at two sites on D0, the domain that enhances the binding of KIR3D to HLA class I. HLA-B variants that gained Bw4 through interallelic microconversion are also products of selection. A worldwide comparison uncovers unusual KIR3DL1/S1 evolution in modern sub-Saharan Africans. Balancing selection is weak and confined to D0, KIR3DS1 is rare and KIR3DL1 allotypes with similar binding sites predominate. Natural killer cells express the dominant KIR3DL1 at a high frequency and with high surface density, providing strong responses to cells perturbed in Bw4 expression. 相似文献
16.
Anthropogenic greenhouse gas contribution to flood risk in England and Wales in autumn 2000 总被引:6,自引:0,他引:6
Pall P Aina T Stone DA Stott PA Nozawa T Hilberts AG Lohmann D Allen MR 《Nature》2011,470(7334):382-385
Interest in attributing the risk of damaging weather-related events to anthropogenic climate change is increasing. Yet climate models used to study the attribution problem typically do not resolve the weather systems associated with damaging events such as the UK floods of October and November 2000. Occurring during the wettest autumn in England and Wales since records began in 1766, these floods damaged nearly 10,000 properties across that region, disrupted services severely, and caused insured losses estimated at £1.3 billion (refs 5, 6). Although the flooding was deemed a 'wake-up call' to the impacts of climate change at the time, such claims are typically supported only by general thermodynamic arguments that suggest increased extreme precipitation under global warming, but fail to account fully for the complex hydrometeorology associated with flooding. Here we present a multi-step, physically based 'probabilistic event attribution' framework showing that it is very likely that global anthropogenic greenhouse gas emissions substantially increased the risk of flood occurrence in England and Wales in autumn 2000. Using publicly volunteered distributed computing, we generate several thousand seasonal-forecast-resolution climate model simulations of autumn 2000 weather, both under realistic conditions, and under conditions as they might have been had these greenhouse gas emissions and the resulting large-scale warming never occurred. Results are fed into a precipitation-runoff model that is used to simulate severe daily river runoff events in England and Wales (proxy indicators of flood events). The precise magnitude of the anthropogenic contribution remains uncertain, but in nine out of ten cases our model results indicate that twentieth-century anthropogenic greenhouse gas emissions increased the risk of floods occurring in England and Wales in autumn 2000 by more than 20%, and in two out of three cases by more than 90%. 相似文献