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1 Introduction Metal, metal oxide and metal compound nanoparticles (NPs) received considerable attention due to their unique properties: catalytic, magnetic, optical, electronic, etc. We believe that for different applications, there are preferable morphologies of NP-stabilizing medium composites. For example, small (1-3 nm) nanoparticles formed in micro/mesoporous hypercrosslinked polystyrene demonstrate excellent catalytic properties in various hydrogenation and oxidation reactions due to high surface... 相似文献
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McCarroll SA Hadnott TN Perry GH Sabeti PC Zody MC Barrett JC Dallaire S Gabriel SB Lee C Daly MJ Altshuler DM;International HapMap Consortium 《Nature genetics》2006,38(1):86-92
The locations and properties of common deletion variants in the human genome are largely unknown. We describe a systematic method for using dense SNP genotype data to discover deletions and its application to data from the International HapMap Consortium to characterize and catalogue segregating deletion variants across the human genome. We identified 541 deletion variants (94% novel) ranging from 1 kb to 745 kb in size; 278 of these variants were observed in multiple, unrelated individuals, 120 in the homozygous state. The coding exons of ten expressed genes were found to be commonly deleted, including multiple genes with roles in sex steroid metabolism, olfaction and drug response. These common deletion polymorphisms typically represent ancestral mutations that are in linkage disequilibrium with nearby SNPs, meaning that their association to disease can often be evaluated in the course of SNP-based whole-genome association studies. 相似文献
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van de Laar IM Oldenburg RA Pals G Roos-Hesselink JW de Graaf BM Verhagen JM Hoedemaekers YM Willemsen R Severijnen LA Venselaar H Vriend G Pattynama PM Collée M Majoor-Krakauer D Poldermans D Frohn-Mulder IM Micha D Timmermans J Hilhorst-Hofstee Y Bierma-Zeinstra SM Willems PJ Kros JM Oei EH Oostra BA Wessels MW Bertoli-Avella AM 《Nature genetics》2011,43(2):121-126
Thoracic aortic aneurysms and dissections are a main feature of connective tissue disorders, such as Marfan syndrome and Loeys-Dietz syndrome. We delineated a new syndrome presenting with aneurysms, dissections and tortuosity throughout the arterial tree in association with mild craniofacial features and skeletal and cutaneous anomalies. In contrast with other aneurysm syndromes, most of these affected individuals presented with early-onset osteoarthritis. We mapped the genetic locus to chromosome 15q22.2-24.2 and show that the disease is caused by mutations in SMAD3. This gene encodes a member of the TGF-β pathway that is essential for TGF-β signal transmission. SMAD3 mutations lead to increased aortic expression of several key players in the TGF-β pathway, including SMAD3. Molecular diagnosis will allow early and reliable identification of cases and relatives at risk for major cardiovascular complications. Our findings endorse the TGF-β pathway as the primary pharmacological target for the development of new treatments for aortic aneurysms and osteoarthritis. 相似文献
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The weighted linear choice model is one of the most popular models in the social sciences. In this model the utility of a choice object is represented as a weighted sum of attribute-level desirabilities, where the weights are attribute importances. In many empirical contexts the choice objects are such that individuals are highly correlated in terms of their desirability ordering of levels within attribute (e.g., price levels, durability levels, etc.) but may differ appreciably in terms of their evaluations of each attribute's importance.In this paper we address the problem of how dissimilar two individuals may be, in a rank correlation sense, given that they agree completely on the desirability ordering of levels within attributes, but may disagree considerably regarding the importance they attach to the attributes themselves. The problem has interesting implications regarding the potential value of clustering individuals' utility functions for market segmentation or other such purposes.The authors would like to thank the editor and three anonymous reviewers for their excellent comments on an earlier draft of the paper. 相似文献