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71.
Systemic Practice and Action Research - Adopting a systems thinking perspective, this study establishes the micro-foundation of two distinct behavior modes in the context of operational... 相似文献
72.
Reconstruction of gene association network reveals a transmembrane protein required for adipogenesis and targeted by PPARγ 总被引:1,自引:0,他引:1
Juliane G. Bogner-Strauss Andreas Prokesch Fatima Sanchez-Cabo Dietmar Rieder Hubert Hackl Kalina Duszka Anne Krogsdam Barbara Di Camillo Evelyn Walenta Ariane Klatzer Achim Lass Montserrat Pinent Wing-Cheong Wong Frank Eisenhaber Zlatko Trajanoski 《Cellular and molecular life sciences : CMLS》2010,67(23):4049-4064
73.
Modelling and Trading the Greek Stock Market with Gene Expression and Genetic Programing Algorithms
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Andreas Karatahansopoulos Georgios Sermpinis Jason Laws Christian Dunis 《Journal of forecasting》2014,33(8):596-610
This paper presents an application of the gene expression programming (GEP) and integrated genetic programming (GP) algorithms to the modelling of ASE 20 Greek index. GEP and GP are robust evolutionary algorithms that evolve computer programs in the form of mathematical expressions, decision trees or logical expressions. The results indicate that GEP and GP produce significant trading performance when applied to ASE 20 and outperform the well‐known existing methods. The trading performance of the derived models is further enhanced by applying a leverage filter. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
74.
Andreas Blank 《Annals of science》2013,70(2):184-209
This article studies the theory of animal seeds as purely material entities in the early seventeenth-century medical writings of Antonio Ponce Santacruz, royal physician to the Spanish king Philipp IV. Santacruz adopts the theory of the eduction of substantial forms from the potentiality of matter, according to which new kinds of causal powers can arise out of material composites of a certain complexity. Santacruz stands out among the late Aristotelian defenders of eduction theory because he applies the concept of an instrument of direction developed by the medieval Avicenna commentator Gentile da Foligno and gives a novel turn to this concept by interpreting animal seeds as separate instruments. The article situates Santacruz's theory in the context of early modern debates about the concept of the eduction of forms, as well as in the context of early modern debates about the concept of separate instruments. Particular attention is paid to Santacruz's responses to the biological views of Julius Caesar Scaliger and Thomas Feyens. Santacruz's response to Scaliger turns out to be central for his explication of the eduction relation, and Santacruz's response to Feyens turns out to be central for his explication of the nature of instrumental causation. 相似文献
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Gemoll T Habermann JK Lahmann J Szymczak S Lundgren C Bündgen NK Jungbluth T Nordström B Becker S Lomnytska MI Bruch HP Ziegler A Hellman U Auer G Roblick UJ Jörnvall H 《Cellular and molecular life sciences : CMLS》2012,69(2):325-333
DNA aneuploidy has been identified as a prognostic factor in the majority of epithelial malignancies. We aimed at identifying ploidy-associated protein expression in endometrial cancer of different prognostic subgroups. Comparison of gel electrophoresis-based protein expression patterns between normal endometrium (n?=?5), diploid (n?=?7), and aneuploid (n?=?7) endometrial carcinoma detected 121 ploidy-associated protein forms, 42 differentially expressed between normal endometrium and diploid endometrioid carcinomas, 37 between diploid and aneuploid endometrioid carcinomas, and 41 between diploid endometrioid and aneuploid uterine papillary serous cancer. Proteins were identified by mass spectrometry and evaluated by Ingenuity Pathway Analysis. Targets were confirmed by liquid chromatography/mass spectrometry. Mass spectrometry identified 41 distinct polypeptides and pathway analysis resulted in high-ranked networks with vimentin and Nf-κB as central nodes. These results identify ploidy-associated protein expression differences that overrule histopathology-associated expression differences and emphasize particular protein networks in genomic stability of endometrial cancer. 相似文献
78.
Singh R Hoogaars WM Barnett P Grieskamp T Rana MS Buermans H Farin HF Petry M Heallen T Martin JF Moorman AF 't Hoen PA Kispert A Christoffels VM 《Cellular and molecular life sciences : CMLS》2012,69(8):1377-1389
A key step in heart development is the coordinated development of the atrioventricular canal (AVC), the constriction between the atria and ventricles that electrically and physically separates the chambers, and the development of the atrioventricular valves that ensure unidirectional blood flow. Using knock-out and inducible overexpression mouse models, we provide evidence that the developmentally important T-box factors Tbx2 and Tbx3, in a functionally redundant manner, maintain the AVC myocardium phenotype during the process of chamber differentiation. Expression profiling and ChIP-sequencing analysis of Tbx3 revealed that it directly interacts with and represses chamber myocardial genes, and induces the atrioventricular pacemaker-like phenotype by activating relevant genes. Moreover, mutant mice lacking 3 or 4 functional alleles of Tbx2 and Tbx3 failed to form atrioventricular cushions, precursors of the valves and septa. Tbx2 and Tbx3 trigger development of the cushions through a regulatory feed-forward loop with Bmp2, thus providing a mechanism for the co-localization and coordination of these important processes in heart development. 相似文献
79.
Whole-genome sequence of Schistosoma haematobium 总被引:1,自引:0,他引:1
Young ND Jex AR Li B Liu S Yang L Xiong Z Li Y Cantacessi C Hall RS Xu X Chen F Wu X Zerlotini A Oliveira G Hofmann A Zhang G Fang X Kang Y Campbell BE Loukas A Ranganathan S Rollinson D Rinaldi G Brindley PJ Yang H Wang J Wang J Gasser RB 《Nature genetics》2012,44(2):221-225
Schistosomiasis is a neglected tropical disease caused by blood flukes (genus Schistosoma; schistosomes) and affecting 200 million people worldwide. No vaccines are available, and treatment relies on one drug, praziquantel. Schistosoma haematobium has come into the spotlight as a major cause of urogenital disease, as an agent linked to bladder cancer and as a predisposing factor for HIV/AIDS. The parasite is transmitted to humans from freshwater snails. Worms dwell in blood vessels and release eggs that become embedded in the bladder wall to elicit chronic immune-mediated disease and induce squamous cell carcinoma. Here we sequenced the 385-Mb genome of S. haematobium using Illumina-based technology at 74-fold coverage and compared it to sequences from related parasites. We included genome annotation based on function, gene ontology, networking and pathway mapping. This genome now provides an unprecedented resource for many fundamental research areas and shows great promise for the design of new disease interventions. 相似文献
80.
Comas I Borrell S Roetzer A Rose G Malla B Kato-Maeda M Galagan J Niemann S Gagneux S 《Nature genetics》2012,44(1):106-110
Epidemics of drug-resistant bacteria emerge worldwide, even as resistant strains frequently have reduced fitness compared to their drug-susceptible counterparts. Data from model systems suggest that the fitness cost of antimicrobial resistance can be reduced by compensatory mutations; however, there is limited evidence that compensatory evolution has any significant role in the success of drug-resistant bacteria in human populations. Here we describe a set of compensatory mutations in the RNA polymerase genes of rifampicin-resistant M. tuberculosis, the etiologic agent of human tuberculosis (TB). M. tuberculosis strains harboring these compensatory mutations showed a high competitive fitness in vitro. Moreover, these mutations were associated with high fitness in vivo, as determined by examining their relative clinical frequency across patient populations. Of note, in countries with the world's highest incidence of multidrug-resistant (MDR) TB, more than 30% of MDR clinical isolates had this form of mutation. Our findings support a role for compensatory evolution in the global epidemics of MDR TB. 相似文献