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31.
Lately, society has pressed for more direct societal relevance of social research. The argument of this special issue is that engaged research is an answer to the demand for a social science that matters. We define engaged research as a praxis where researchers actively engage in a social field in the pursuit of solving important local problems, while at the same time combining this with a scientific knowledge generation process. In other words, we discuss the conditions for research when researchers “go native” to solve problems and reflect along with participants. We have been able to find several sources of arguments supporting such a research strategy, but our search for methodological guidance on how to act as an engaged researcher has been in vain. What does it take for a researcher to do engaged research? The set of articles in this special issue all address certain aspects of this challenge. Some discuss the researcher’s path towards deep field engagement, whereas others discover various challenges and skills involved in engagement, and the task of developing scientific knowledge based on engaged research. 相似文献
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Cotton RG; Human Variome Project Appelbe W Auerbach AD Becker K Bodmer W Boone DJ Boulyjenkov V Brahmachari S Brody L Brookes A Brown AF Byers P Cantu JM Cassiman JJ Claustres M Concannon P Cotton RG den Dunnen JT Flicek P Gibbs R Hall J Hasler J Katz M Kwok PY Laradi S Lindblom A Maglott D Marsh S Masimirembwa CM Minoshima S de Ramirez AM Pagon R Ramesar R Ravine D Richards S Rimoin D Ring HZ Scriver CR Sherry S Shimizu N Stein L Tadmouri GO Taylor G Watson M 《Nature genetics》2007,39(4):433-436
Lists of variations in genomic DNA and their effects have been kept for some time and have been used in diagnostics and research. Although these lists have been carefully gathered and curated, there has been little standardization and coordination, complicating their use. Given the myriad possible variations in the estimated 24,000 genes in the human genome, it would be useful to have standard criteria for databases of variation. Incomplete collection and ascertainment of variants demonstrates a need for a universally accessible system. These and other problems led to the World Heath Organization-cosponsored meeting on June 20-23, 2006 in Melbourne, Australia, which launched the Human Variome Project. This meeting addressed all areas of human genetics relevant to collection of information on variation and its effects. Members of each of eight sessions (the clinic and phenotype, the diagnostic laboratory, the research laboratory, curation and collection, informatics, relevance to the emerging world, integration and federation and funding and sustainability) developed a number of recommendations that were then organized into a total of 96 recommendations to act as a foundation for future work worldwide. Here we summarize the background of the project, the meeting and its recommendations. 相似文献
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Solutions for a cultivated planet 总被引:61,自引:0,他引:61
Foley JA Ramankutty N Brauman KA Cassidy ES Gerber JS Johnston M Mueller ND O'Connell C Ray DK West PC Balzer C Bennett EM Carpenter SR Hill J Monfreda C Polasky S Rockström J Sheehan J Siebert S Tilman D Zaks DP 《Nature》2011,478(7369):337-342
Increasing population and consumption are placing unprecedented demands on agriculture and natural resources. Today, approximately a billion people are chronically malnourished while our agricultural systems are concurrently degrading land, water, biodiversity and climate on a global scale. To meet the world's future food security and sustainability needs, food production must grow substantially while, at the same time, agriculture's environmental footprint must shrink dramatically. Here we analyse solutions to this dilemma, showing that tremendous progress could be made by halting agricultural expansion, closing 'yield gaps' on underperforming lands, increasing cropping efficiency, shifting diets and reducing waste. Together, these strategies could double food production while greatly reducing the environmental impacts of agriculture. 相似文献
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Neural networks are fitted to real exchange rates of several industrialized countries. The size and topology of the networks is found through the use of multiple correlation coefficients, principal component analysis of residuals and graphical analysis of network output per hidden layer cell and input layer cell. These pruned neural networks are good approximations to varying non‐linear trends in real exchange rates. Non‐linear dynamic analysis shows that the long‐term equilibrium values of several European currencies correspond to the actual values within the European Monetary System. Based on its long‐term equilibrium value, the Euro appears to be undervalued vis‐à‐vis the US dollar at the introduction of the Euro on 1 January 1999. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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Systemic Practice and Action Research - In the premodern age, societies seeking knowledge went to myth, tradition, or religion for guidance. In the modern age, the university institution is... 相似文献
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Molenaar JJ Koster J Zwijnenburg DA van Sluis P Valentijn LJ van der Ploeg I Hamdi M van Nes J Westerman BA van Arkel J Ebus ME Haneveld F Lakeman A Schild L Molenaar P Stroeken P van Noesel MM Ora I Santo EE Caron HN Westerhout EM Versteeg R 《Nature》2012,483(7391):589-593
Neuroblastoma is a childhood tumour of the peripheral sympathetic nervous system. The pathogenesis has for a long time been quite enigmatic, as only very few gene defects were identified in this often lethal tumour. Frequently detected gene alterations are limited to MYCN amplification (20%) and ALK activations (7%). Here we present a whole-genome sequence analysis of 87 neuroblastoma of all stages. Few recurrent amino-acid-changing mutations were found. In contrast, analysis of structural defects identified a local shredding of chromosomes, known as chromothripsis, in 18% of high-stage neuroblastoma. These tumours are associated with a poor outcome. Structural alterations recurrently affected ODZ3, PTPRD and CSMD1, which are involved in neuronal growth cone stabilization. In addition, ATRX, TIAM1 and a series of regulators of the Rac/Rho pathway were mutated, further implicating defects in neuritogenesis in neuroblastoma. Most tumours with defects in these genes were aggressive high-stage neuroblastomas, but did not carry MYCN amplifications. The genomic landscape of neuroblastoma therefore reveals two novel molecular defects, chromothripsis and neuritogenesis gene alterations, which frequently occur in high-risk tumours. 相似文献
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Tumour suppressor RNF43 is a stem-cell E3 ligase that induces endocytosis of Wnt receptors 总被引:1,自引:0,他引:1
BK Koo M Spit I Jordens TY Low DE Stange M van de Wetering JH van Es S Mohammed AJ Heck MM Maurice H Clevers 《Nature》2012,488(7413):665-669
LGR5+ stem cells reside at crypt bottoms, intermingled with Paneth cells that provide Wnt, Notch and epidermal growth factor signals. Here we find that the related RNF43 and ZNRF3 transmembrane E3 ubiquitin ligases are uniquely expressed in LGR5+ stem cells. Simultaneous deletion of the two genes encoding these proteins in the intestinal epithelium of mice induces rapidly growing adenomas containing high numbers of Paneth and LGR5+ stem cells. In vitro, growth of organoids derived from these adenomas is arrested when Wnt secretion is inhibited, indicating a dependence of the adenoma stem cells on Wnt produced by adenoma Paneth cells. In the HEK293T human cancer cell line, expression of RNF43 blocks Wnt responses and targets surface-expressed frizzled receptors to lysosomes. In the RNF43-mutant colorectal cancer cell line HCT116, reconstitution of RNF43 expression removes its response to exogenous Wnt. We conclude that RNF43 and ZNRF3 reduce Wnt signals by selectively ubiquitinating frizzled receptors, thereby targeting these Wnt receptors for degradation. 相似文献
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Genome-wide association study identifies multiple loci influencing human serum metabolite levels 总被引:1,自引:0,他引:1
Kettunen J Tukiainen T Sarin AP Ortega-Alonso A Tikkanen E Lyytikäinen LP Kangas AJ Soininen P Würtz P Silander K Dick DM Rose RJ Savolainen MJ Viikari J Kähönen M Lehtimäki T Pietiläinen KH Inouye M McCarthy MI Jula A Eriksson J Raitakari OT Salomaa V Kaprio J Järvelin MR Peltonen L Perola M Freimer NB Ala-Korpela M Palotie A Ripatti S 《Nature genetics》2012,44(3):269-276
Nuclear magnetic resonance assays allow for measurement of a wide range of metabolic phenotypes. We report here the results of a GWAS on 8,330 Finnish individuals genotyped and imputed at 7.7 million SNPs for a range of 216 serum metabolic phenotypes assessed by NMR of serum samples. We identified significant associations (P < 2.31 × 10(-10)) at 31 loci, including 11 for which there have not been previous reports of associations to a metabolic trait or disorder. Analyses of Finnish twin pairs suggested that the metabolic measures reported here show higher heritability than comparable conventional metabolic phenotypes. In accordance with our expectations, SNPs at the 31 loci associated with individual metabolites account for a greater proportion of the genetic component of trait variance (up to 40%) than is typically observed for conventional serum metabolic phenotypes. The identification of such associations may provide substantial insight into cardiometabolic disorders. 相似文献
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Brown KM Macgregor S Montgomery GW Craig DW Zhao ZZ Iyadurai K Henders AK Homer N Campbell MJ Stark M Thomas S Schmid H Holland EA Gillanders EM Duffy DL Maskiell JA Jetann J Ferguson M Stephan DA Cust AE Whiteman D Green A Olsson H Puig S Ghiorzo P Hansson J Demenais F Goldstein AM Gruis NA Elder DE Bishop JN Kefford RF Giles GG Armstrong BK Aitken JF Hopper JL Martin NG Trent JM Mann GJ Hayward NK 《Nature genetics》2008,40(7):838-840
We conducted a genome-wide association pooling study for cutaneous melanoma and performed validation in samples totaling 2,019 cases and 2,105 controls. Using pooling, we identified a new melanoma risk locus on chromosome 20 (rs910873 and rs1885120), with replication in two further samples (combined P < 1 x 10(-15)). The per allele odds ratio was 1.75 (1.53, 2.01), with evidence for stronger association in early-onset cases. 相似文献