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81.
Houlden H Johnson J Gardner-Thorpe C Lashley T Hernandez D Worth P Singleton AB Hilton DA Holton J Revesz T Davis MB Giunti P Giunti P Wood NW 《Nature genetics》2007,39(12):1434-1436
The microtubule-associated protein tau (encoded by MAPT) and several tau kinases have been implicated in neurodegeneration, but only MAPT has a proven role in disease. We identified mutations in the gene encoding tau tubulin kinase 2 (TTBK2) as the cause of spinocerebellar ataxia type 11. Affected brain tissue showed substantial cerebellar degeneration and tau deposition. These data suggest that TTBK2 is important in the tau cascade and in spinocerebellar degeneration. 相似文献
82.
MacArthur DG Seto JT Raftery JM Quinlan KG Huttley GA Hook JW Lemckert FA Kee AJ Edwards MR Berman Y Hardeman EC Gunning PW Easteal S Yang N North KN 《Nature genetics》2007,39(10):1261-1265
More than a billion humans worldwide are predicted to be completely deficient in the fast skeletal muscle fiber protein alpha-actinin-3 owing to homozygosity for a premature stop codon polymorphism, R577X, in the ACTN3 gene. The R577X polymorphism is associated with elite athlete status and human muscle performance, suggesting that alpha-actinin-3 deficiency influences the function of fast muscle fibers. Here we show that loss of alpha-actinin-3 expression in a knockout mouse model results in a shift in muscle metabolism toward the more efficient aerobic pathway and an increase in intrinsic endurance performance. In addition, we demonstrate that the genomic region surrounding the 577X null allele shows low levels of genetic variation and recombination in individuals of European and East Asian descent, consistent with strong, recent positive selection. We propose that the 577X allele has been positively selected in some human populations owing to its effect on skeletal muscle metabolism. 相似文献
83.
Ethanol, 3 g/kg i.p., did not significantly alter the acute toxicity of amphetamine in the mouse. However, the urinary metabolite pattern was changed, suggesting that ethanol suppressed metabolism of the stimulant during the initial 6 h period. After 24 h, the mouse metabolized the same fraction of a given dose of amphetamine, whether it was given as amphetamine alone or amphetamine mixed with 2,3 or 4 g/kg ethanol. 相似文献
84.
5-Methylcytosine localised in mammalian constitutive heterochromatin 总被引:26,自引:0,他引:26
85.
The positive impacts of managing projects as a portfolio are quantified by comparing the value of the integrated risk of a project portfolio and the aggregation of single project risks implemented separately. Firstly, the integrated risk is defined by proposing risky events based on set theory. Secondly, as projects interact with each other in a project portfolio, the integrated risk is evaluated by using a Bayesian network structure learning algorithm to construct an interdependent network of risks. Finally, the integrated risk of a practical case is assessed using this method, and the results show that the proposed method is an effective tool for calculating the extent of risk reduction of implementing a project portfolio and identifying the most risky project, so as to assist companies in making comprehensive decisions in the phase of portfolio selection and portfolio controlling. 相似文献
86.
A hybrid approach of DEA (data envelopment analysis) and TOPSIS (technique for order performance (preference) by similarity
to ideal solution) is proposed for multiple criteria decision analysis in emergency management. Two DEA-based optimization
models are constructed to facilitate identifying parameter information regarding criterion weights and quantifying qualitative
criteria in TOPSIS. An emergency management case study utilizing data from the Emergency Management Australia (EMA) Disasters
Database is provided to demonstrate the feasibility of the proposed analysis procedure. 相似文献
87.
A Maturing of Systems Thinking? Evidence from Three Perspectives 总被引:1,自引:2,他引:1
Barton John Emery Merrelyn Flood Robert Louis Selsky John W. Wolstenholme Eric 《Systemic Practice and Action Research》2004,17(1):3-36
This paper reviews trends in systems theory/thinking from the 1970s to the early 2000s. It proposes a maturation of the field based on certain conceptual and methodological advances that have sought to liberate systems thinking from earlier strictures. An edited dialogue among three prominent systems thinkers from different systems schools—Merrelyn Emery, Bob Flood, and Eric Wolstenholme—provides evidence. Similarities and differences are identified, complementarities among the schools are derived and analyzed, and trajectories for future research are indicated. 相似文献
88.
89.
A multiple criteria decision analysis(MCDA) approach is designed for capturing the relative preference information of a decision maker involved in a conflict.More specifically,an MCDA approach based on the outranking method,ELECTRE III,is employed for ranking states or possible scenarios in the conflict from most to least preferred,where ties are allowed,for a decision maker according to his or her value system.To demonstrate how this preference elicitation methodology can be conveniently implemented in practice within the framework of the Graph Model for Conflict Resolution,it is applied to a real world water supply crisis which occurred in the town of North Battleford,located in the Canadian province of Saskatchewan. 相似文献
90.
The Open-Systems Thinking (OST) school identified with Emery and Trist is situated as an important but underutilized approach in systems thinking. The main features of OST are described, including four "tracks" along which OST has developed. The third track, which focuses on interorganizational domains, is considered in detail. It is then applied to a case concerning the complex social dynamics of and in port domains in New Zealand. This exercise enables us to illuminate some lacunae in previous representations of the port domain research, to assess OST's third track regarding its relevance for systemic practice, and to help to bring OST to the table with other systems approaches that are all vying for the attention of researchers, practicing managers, students, and consultants. 相似文献