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81.
The earliest record of human activity in northern Europe 总被引:1,自引:0,他引:1
Parfitt SA Barendregt RW Breda M Candy I Collins MJ Coope GR Durbidge P Field MH Lee JR Lister AM Mutch R Penkman KE Preece RC Rose J Stringer CB Symmons R Whittaker JE Wymer JJ Stuart AJ 《Nature》2005,438(7070):1008-1012
The colonization of Eurasia by early humans is a key event after their spread out of Africa, but the nature, timing and ecological context of the earliest human occupation of northwest Europe is uncertain and has been the subject of intense debate. The southern Caucasus was occupied about 1.8 million years (Myr) ago, whereas human remains from Atapuerca-TD6, Spain (more than 780 kyr ago) and Ceprano, Italy (about 800 kyr ago) show that early Homo had dispersed to the Mediterranean hinterland before the Brunhes-Matuyama magnetic polarity reversal (780 kyr ago). Until now, the earliest uncontested artefacts from northern Europe were much younger, suggesting that humans were unable to colonize northern latitudes until about 500 kyr ago. Here we report flint artefacts from the Cromer Forest-bed Formation at Pakefield (52 degrees N), Suffolk, UK, from an interglacial sequence yielding a diverse range of plant and animal fossils. Event and lithostratigraphy, palaeomagnetism, amino acid geochronology and biostratigraphy indicate that the artefacts date to the early part of the Brunhes Chron (about 700 kyr ago) and thus represent the earliest unequivocal evidence for human presence north of the Alps. 相似文献
82.
Rual JF Venkatesan K Hao T Hirozane-Kishikawa T Dricot A Li N Berriz GF Gibbons FD Dreze M Ayivi-Guedehoussou N Klitgord N Simon C Boxem M Milstein S Rosenberg J Goldberg DS Zhang LV Wong SL Franklin G Li S Albala JS Lim J Fraughton C Llamosas E Cevik S Bex C Lamesch P Sikorski RS Vandenhaute J Zoghbi HY Smolyar A Bosak S Sequerra R Doucette-Stamm L Cusick ME Hill DE Roth FP Vidal M 《Nature》2005,437(7062):1173-1178
Systematic mapping of protein-protein interactions, or 'interactome' mapping, was initiated in model organisms, starting with defined biological processes and then expanding to the scale of the proteome. Although far from complete, such maps have revealed global topological and dynamic features of interactome networks that relate to known biological properties, suggesting that a human interactome map will provide insight into development and disease mechanisms at a systems level. Here we describe an initial version of a proteome-scale map of human binary protein-protein interactions. Using a stringent, high-throughput yeast two-hybrid system, we tested pairwise interactions among the products of approximately 8,100 currently available Gateway-cloned open reading frames and detected approximately 2,800 interactions. This data set, called CCSB-HI1, has a verification rate of approximately 78% as revealed by an independent co-affinity purification assay, and correlates significantly with other biological attributes. The CCSB-HI1 data set increases by approximately 70% the set of available binary interactions within the tested space and reveals more than 300 new connections to over 100 disease-associated proteins. This work represents an important step towards a systematic and comprehensive human interactome project. 相似文献
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85.
José L. Moreno Stuart C. Sealfon Javier González-Maeso 《Cellular and molecular life sciences : CMLS》2009,66(23):3777-3785
Schizophrenia is one of the most common mental illnesses, with hereditary and environmental factors important for its etiology.
All antipsychotics have in common a high affinity for monoaminergic receptors. Whereas hallucinations and delusions usually
respond to typical (haloperidol-like) and atypical (clozapine-like) monoaminergic antipsychotics, their efficacy in improving
negative symptoms and cognitive deficits remains inadequate. In addition, devastating side effects are a common characteristic
of monoaminergic antipsychotics. Recent biochemical, preclinical and clinical findings support group II metabotropic glutamate
receptors (mGluR2 and mGluR3) as a new approach to treat schizophrenia. This paper reviews the status of general knowledge
of mGluR2 and mGluR3 in the psychopharmacology, genetics and neuropathology of schizophrenia 相似文献
86.
James Ladyman Stuart Presnell Anthony J. Short 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2008,39(2):315-324
When considering controversial thermodynamic scenarios such as Maxwell's demon, it is often necessary to consider probabilistic mixtures of macrostates. This raises the question of how, if at all, to assign entropy to them. The information-theoretic entropy is often used in such cases; however, no general proof of the soundness of doing so has been given, and indeed some arguments against doing so have been presented. We offer a general proof of the applicability of the information-theoretic entropy to probabilistic mixtures of macrostates that is based upon a probabilistic generalisation of the Kelvin statement of the second law. We defend the latter and make clear the other assumptions on which our main result depends. We also briefly discuss the interpretation of our result. 相似文献
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88.
Bryan L. Stuart Hannah E. Som Thy Neang Huy Duc Hoang Duong Thi Thuy Le Vinh Quang Dau 《Journal of Natural History》2020,54(1-4):225-255
ABSTRACT Species boundaries within the red-eyed Leptobrachium of southern Indochina have been uncertain. Leptobrachium pullum and L. mouhoti from upper and lower elevations, respectively, of the Langbian Plateau of southern Vietnam and eastern Cambodia differ in body size but have relatively low interspecific mitochondrial DNA divergence, leading to speculation that these might represent a single species with an elevational cline in body size. The recent discovery of an allopatric high-elevation population of red-eyed Leptobrachium on the Kon Tum Plateau (= Central Highlands) of north-eastern Cambodia and central Vietnam has been referred to both species, and to a putatively undescribed species. We examine variation in morphology of adults and tadpoles, mitochondrial DNA, 11 nuclear genes and advertisement calls, and show corroborating lines of evidence for the existence of three species of red-eyed Leptobrachium in southern Indochina. Although the three species are reciprocally monophyletic in mitochondrial DNA, their shallow mitochondrial DNA divergences are not mirrored by morphology, advertisement calls, or – in part – nuclear DNA, and probably reflect past mitochondrial introgression rather than recent speciation. The Central Highlands taxon is described herein as a new species. http://www.zoobank.org/urn:lsid:zoobank.org:pub:CE6650AF-D9FB-40F4-8A2E-9B4E23AAC205 相似文献
89.
从地方性艺术市场的角度对意大利佛罗伦萨的当代艺术体系进行分析,可以发现,佛罗伦萨的困境在于:既要充分利用其独一无二的艺术历史,又要保持活跃的当代艺术氛围。佛罗伦萨与颇具代表性的美国密苏里州圣路易斯市的地方性艺术市场截然不同。现今佛罗伦萨艺术体系中存在的问题可以从历史和以大众旅游为中心的现有生活方式中体现出来。 相似文献
90.
Leptothorax (Nesomyrmex) spininodis andL. (N.) echinatinodis workers lay pheromone trails when returning from food sources to their nests. Workers from within the nest begin following the trail almost immediately upon the successful forager's return and do not require a leader. The trail remains effective for about four minutes under our laboratory conditions but it is unclear whether the trail alone is sufficient to induce recruitment or whether additional signals, perhaps emitted within the nest, are involved. Pheromone trails of this type have not previously been documented for leptothoracine ants. 相似文献