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11.
Gert A.Schultz 《北京师范大学学报(自然科学版)》2010,46(3)
大多数关于气候变化对水文过程影响评估的文献中,对大气模型中存在的显著的不确定性往往考虑不足.在很多重要的领域,GCM生成的长期预测很少能用于未来水资源规划与管理,因为其结果无法对变化趋势进行准确的描述,也就是对水文变量增加或减少趋势的预测缺乏可信度.一项借助于14个GCM模型以及不同发展情景(包括基准情景)开展的径流预报集合分析研究验证了这一点.GCM的输出情景作为水平衡模型的输入这种方法用于多瑙河上游未来水文变化的预测.如果将这种预测情景用于预测由气候变化引起的水文变化经济成本,更大的不确定性将会在经济数学模型中产生.著名的Stern"气候变化经济学"评论在水资源管理领域被广泛的应用.在经济学文献中对Stern评论的观点存在很多争议,很多专家对方法的使用和结论提出了一些质疑,本文的实例也证明了这一点.因此,进行气候变化对水文和水资源影响评估的学者们应该意识到不仅在GCM中存在很大的不确定性,大气-水文-经济模型的耦合过程可能会导致更大的不确定性. 相似文献
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Gert Assmus 《Journal of forecasting》1984,3(2):121-138
Forecasting new-product performance has been called ‘one of the most difficult and critical management tasks’. It has attracted considerable attention because of the magnitude of the resources devoted to product development and because of the sizeable risks involved in making the go–no-go decisions. In comparison with forecasting sales for established products, there is no sales history, or more generally, the company has no product specific experience related to consumer acceptance, trade support and competitive reactions. This article first presents a review of new product forecasting techniques with an emphasis given to the more recent developments in forecasting models. Then, forecasting procedures are assessed by discussing their benefits and their costs. The third part of the article discusses trends in new product forecasting. 相似文献
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Sarah Strohkamp Timo Gemoll Sina Humborg Sonja Hartwig Stefan Lehr Sandra Freitag-Wolf Susanne Becker Bo Franzén Ralph Pries Barbara Wollenberg Uwe J. Roblick Hans-Peter Bruch Tobias Keck Gert Auer Jens K. Habermann 《Cellular and molecular life sciences : CMLS》2018,75(2):323-334
Colorectal cancer (CRC) is one of the most frequent malignancies in the Western world. Early tumor detection and intervention are important determinants on CRC patient survival. During early tumor proliferation, dissemination and angiogenesis, platelets store and segregate proteins actively and selectively. Hence, the platelet proteome is a potential source of biomarkers denoting early malignancy. By comparing protein profiles of platelets between healthy volunteers (n = 12) and patients with early- (n = 7) and late-stage (n = 5) CRCs using multiplex fluorescence two-dimensional gel electrophoresis (2D-DIGE), we aimed at identifying differentially regulated proteins within platelets. By inter-group comparisons, 94 differentially expressed protein spots were detected (p < 0.05) between healthy controls and patients with early- and late-stage CRCs and revealed distinct separations between all three groups in principal component analyses. 54 proteins of interest were identified by mass spectrometry and resulted in high-ranked Ingenuity Pathway Analysis networks associated with Cellular function and maintenance, Cellular assembly and organization, Developmental disorder and Organismal injury and abnormalities (p < 0.0001 to p = 0.0495). Target proteins were validated by multiplex fluorescence-based Western blot analyses using an additional, independent cohort of platelet protein samples [healthy controls (n = 15), early-stage CRCs (n = 15), late-stage CRCs (n = 15)]. Two proteins—clusterin and glutathione synthetase (GSH-S)—featured high impact and were subsequently validated in this independent clinical cohort distinguishing healthy controls from patients with early- and late-stage CRCs. Thus, the potential of clusterin and GSH-S as platelet biomarkers for early detection of CRC could improve existing screening modalities in clinical application and should be confirmed in a prospective multicenter trial. 相似文献
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Kornak U Reynders E Dimopoulou A van Reeuwijk J Fischer B Rajab A Budde B Nürnberg P Foulquier F;ARCL Debré-type Study Group Lefeber D Urban Z Gruenewald S Annaert W Brunner HG van Bokhoven H Wevers R Morava E Matthijs G Van Maldergem L Mundlos S 《Nature genetics》2008,40(1):32-34
We identified loss-of-function mutations in ATP6V0A2, encoding the a2 subunit of the V-type H+ ATPase, in several families with autosomal recessive cutis laxa type II or wrinkly skin syndrome. The mutations result in abnormal glycosylation of serum proteins (CDG-II) and cause an impairment of Golgi trafficking in fibroblasts from affected individuals. These results indicate that the a2 subunit of the proton pump has an important role in Golgi function. 相似文献
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Brumm A Aziz F van den Bergh GD Morwood MJ Moore MW Kurniawan I Hobbs DR Fullagar R 《Nature》2006,441(7093):624-628
In the Soa Basin of central Flores, eastern Indonesia, stratified archaeological sites, including Mata Menge, Boa Lesa and Kobatuwa (Fig. 1), contain stone artefacts associated with the fossilized remains of Stegodon florensis, Komodo dragon, rat and various other taxa. These sites have been dated to 840-700 kyr bp (thousand years before present). The authenticity of the Soa Basin artefacts and their provenance have been demonstrated by previous work, but to quell lingering doubts, here we describe the context, attributes and production modes of 507 artefacts excavated at Mata Menge. We also note specific similarities, and apparent technological continuity, between the Mata Menge stone artefacts and those excavated from Late Pleistocene levels at Liang Bua cave, 50 km to the west. The latter artefacts, dated to between 95-74 and 12 kyr ago, are associated with the remains of a dwarfed descendent of S. florensis, Komodo dragon, rat and a small-bodied hominin species, Homo floresiensis, which had a brain size of about 400 cubic centimetres. The Mata Menge evidence negates claims that stone artefacts associated with H. floresiensis are so complex that they must have been made by modern humans (Homo sapiens). 相似文献
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Gemoll T Roblick UJ Szymczak S Braunschweig T Becker S Igl BW Bruch HP Ziegler A Hellman U Difilippantonio MJ Ried T Jörnvall H Auer G Habermann JK 《Cellular and molecular life sciences : CMLS》2011,68(19):3261-3274
DNA aneuploidy has been identified as a prognostic factor for epithelial malignancies. Further understanding of the translation of DNA aneuploidy into protein expression will help to define novel biomarkers to improve therapies and prognosis. DNA ploidy was assessed by image cytometry. Comparison of gel-electrophoresis-based protein expression patterns of three diploid and four aneuploid colorectal cancer cell lines detected 64 ploidy-associated proteins. Proteins were identified by mass spectrometry and subjected to Ingenuity Pathway Analysis resulting in two overlapping high-ranked networks maintaining Cellular Assembly and Organization, Cell Cycle, and Cellular Growth and Proliferation. CAPZA1, TXNL1, and HDAC2 were significantly validated by Western blotting in cell lines and the latter two showed expression differences also in clinical samples using a tissue microarray of normal mucosa (n?=?19), diploid (n?=?31), and aneuploid (n?=?47) carcinomas. The results suggest that distinct protein expression patterns, affecting TXNL1 and HDAC2, distinguish aneuploid with poor prognosis from diploid colorectal cancers. 相似文献
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Eun-Jung Kim Francisco J. Monje Lin Li Harald Höger Daniela D. Pollak Gert Lubec 《Cellular and molecular life sciences : CMLS》2013,70(4):743-759
The lymphocyte-specific protein tyrosine kinase (Lck), which belongs to the Src kinase-family, is expressed in neurons of the hippocampus, a structure critical for learning and memory. Recent evidence demonstrated a significant downregulation of Lck in Alzheimer’s disease. Lck has additionally been proposed to be a risk factor for Alzheimer’s disease, thus suggesting the involvement of Lck in memory function. The neuronal role of Lck, however, and its involvement in learning and memory remain largely unexplored. Here, in vitro electrophysiology, confocal microscopy, and molecular, pharmacological, genetic and biochemical techniques were combined with in vivo behavioral approaches to examine the role of Lck in the mouse hippocampus. Specific pharmacological inhibition and genetic silencing indicated the involvement of Lck in the regulation of neuritic outgrowth. In the functional pre-established synaptic networks that were examined electrophysiologically, specific Lck-inhibition also selectively impaired the long-term hippocampal synaptic plasticity without affecting spontaneous excitatory synaptic transmission or short-term synaptic potentiation. The selective inhibition of Lck also significantly altered hippocampus-dependent spatial learning and memory in vivo. These data provide the basis for the functional characterization of brain Lck, describing the importance of Lck as a critical regulator of both neuronal morphology and in vivo long-term memory. 相似文献
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Mutations in SEPT9 cause hereditary neuralgic amyotrophy 总被引:7,自引:0,他引:7
Kuhlenbäumer G Hannibal MC Nelis E Schirmacher A Verpoorten N Meuleman J Watts GD De Vriendt E Young P Stögbauer F Halfter H Irobi J Goossens D Del-Favero J Betz BG Hor H Kurlemann G Bird TD Airaksinen E Mononen T Serradell AP Prats JM Van Broeckhoven C De Jonghe P Timmerman V Ringelstein EB Chance PF 《Nature genetics》2005,37(10):1044-1046
Hereditary neuralgic amyotrophy (HNA) is an autosomal dominant recurrent neuropathy affecting the brachial plexus. HNA is triggered by environmental factors such as infection or parturition. We report three mutations in the gene septin 9 (SEPT9) in six families with HNA linked to chromosome 17q25. HNA is the first monogenetic disease caused by mutations in a gene of the septin family. Septins are implicated in formation of the cytoskeleton, cell division and tumorigenesis. 相似文献