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51.
Accumulating evidence strongly suggests that oxidative stress underlies aging processes. Research provides consistent evidence that calorie restriction (CR) reduces age-related oxidative stress and has anti-inflammatory properties. However, information is lacking on the molecular mechanism that would better define the interrelation of reactive oxygen species and nitrogen species and the pro-inflammatory states of the aging process. In this review, the biochemical and molecular bases of the inflammatory process in the aging process are analyzed to delineate the molecular inflammation hypothesis of aging. The key players involved in the proposed hypothesis are the age-related upregulation of NF-kappa B, IL-1 beta, IL-6, TNFalpha, cyclooxygenase-2, and inducible NO synthase, all of which are attenuated by CR. Furthermore, age-related NF kappa B activation is associated with phosphorylation by I kappa B kinase/NIK and MAPKs, while CR blocked these activation processes. The modulation of these factors provides molecular insights of the anti-inflammatory action of CR in relation to the aging process. Based on available finding and our recent supporting evidence, we prefer to use "molecular inflammation" to emphasize the importance of the molecular reaction mechanisms and their aberrance, predisposing to fully expressed chronic inflammatory phenomena. It was further proposed that CR's major force of the regulation of redox-sensitive inflammation may well be its life-prolonging action. 相似文献
52.
53.
Abstract: Picture sorts were used to investigate perceptions of women's office clothes, with a sample of ten male and ten female subjects who normally worked in an office environment. The pictures on the cards were taken from catalogues, and showed women's outfits which might be worn in an office. The subjects sorted the cards repeatedly and generated criteria and categories of their own choice. Some of the criteria and categories had not been previously reported in the clothing research literature. Over half of the male subjects, but none of the female subjects, used ‘married/unmarried woman’ as a sorting criterion, although only one of the images sorted showed a wedding ring. A significantly higher proportion of male than of female subjects used dichotomous categorization (i.e. sorting the cards into two piles for one or more of the criteria). The reasons for this are obscure, but do not appear to be a simple outcome of males not knowing much about female clothing. Previous research into clothing has tended to involve researcher‐centred approaches such as semiotics; the results from this study suggest that there would be advantages in wider use of subject‐centred approaches such as card sorts, both in this domain and elsewhere. It was concluded that card sorts were a useful method and should be more widely used. 相似文献
54.
Kate Sanders Sally Fincher Dennis Bouvier Gary Lewandowski Briana Morrison Laurie Murphy Marian Petre Brad Richards Josh Tenenberg Lynda Thomas Richard Anderson Ruth Anderson Sue Fitzgerald Alicia Gutschow Susan Haller Raymond Lister Renée McCauley John McTaggart Christine Prasad Terry Scott Dermot Shinners-Kennedy Suzanne Westbrook Carol Zander 《Expert Systems》2005,22(3):121-128
Abstract: This paper presents a case study of the use of a repeated single‐criterion card sort with an unusually large, diverse participant group. The study, whose goal was to elicit novice programmers' knowledge of programming concepts, involved over 20 researchers from four continents and 276 participants drawn from 20 different institutions. In this paper we present the design of the study and the unexpected result that there were few discernible systematic differences in the population. The study was one of the activities of the National Science Foundation funded Bootstrapping Research in Computer Science Education project (2003). 相似文献
55.
在系统调查国内流通领域几种主要油脂脂肪酸组成的基础上,对芝麻油掺入其它油品质后脂肪酸组成变化规律进行了详细研究,找出了芝麻油掺伪检验的定性定量依据。 相似文献
56.
We give an O(k · n2) fixed parameter tractable algorithm for the
1-Sided Crossing Minimization. The constant in the running time is the golden ratio
= (1+5)/2 1.618. The constant k is the parameter of the
problem: the number of allowed edge crossings. 相似文献
57.
Photoelectrocatalytic oxidation of o-phenols on copper-plated screen-printed electrodes 总被引:1,自引:0,他引:1
A novel and sensitive detection method based on photoelectrocatalytic oxidation of o-diphenols was demonstrated on a copper-plated screen-printed carbon electrode (designated CuSPE) in pH 8 phosphate buffer solution. The o-diphenols can be detected amperometrically through electrochemical oxidation at a low applied potential of -0.1 V versus Ag/AgCl, where the CuSPE is much less subject to interfering reactions. The mechanism that induces good selectivity of the CuSPE is explained in terms of the formation of a cyclic five-member complex intermediate (Cu(II)-o-quinolate). A prototype homemade flow through cell design is described for incorporating the photoelectrode and light source. Electrode irradiation results in a large increase in anodic current. The oxidative photocurrents produced by irradiation increase with light intensity presumably because of the formation of semiconductor Cu(2)O. The principle used in this study has an opportunity to extend into various research applications. 相似文献
58.
This paper studies leadership dynamics in the development of a knowledge sharing system. We apply the concept of distributed leadership, examining how leadership roles are distributed across different individuals in the organisation during developing and implementing a knowledge sharing system. The results of a case study demonstrate that the leadership was fulfilled by the interdependent and emergent roles played by several individuals: the spearheading and coordinating roles of a knowledgeable and persistent project leader, the supporting and steering roles carried by a group of perceptive and collaboration-inclined executives, and the knowledge sharing and momentum driving roles performed by knowledge champions. Each of these leadership influences was indispensable. None of the leaders could have accomplished this task individually, without the active involvement of the other types of leaders. This research makes its contribution to the understanding of the emergence and dynamics of distributed leadership in the information system environment, and demonstrates the importance of a full awareness of distributed leadership as tasks are carried out in developing a knowledge sharing system. 相似文献
59.
Morgan M. Steffen B. Shafer Belisle Sue B. Watson Gregory L. Boyer Steven W. Wilhelm 《Journal of Great Lakes research》2014
The Laurentian Great Lakes are among the most prominent sources of fresh water in the world. Lake Erie's infamous cyanobacterial blooms have, however, threatened the health of this valuable freshwater resource for decades. Toxic blooms dominated by the cyanobacterium Microcystis aeruginosa have most recently been one of primary ecological concerns for the lake. These toxic blooms impact the availability of potable water, as well as public health and revenues from the tourism and fishery industries. The socioeconomic effects of these blooms have spurred research efforts to pinpoint factors that drive bloom events. Despite decades of research and mitigation efforts, these blooms have expanded both in size and duration in recent years. However, through continued joint efforts between the Canadian and United States governments, scientists, and environmental managers, identification of the factors that drive bloom events is within reach. This review provides a summary of historical and contemporary research efforts in the realm of Lake Erie's harmful cyanobacterial blooms, both in terms of experimental and management achievements and insufficiencies, as well as future directions on the horizon for the lake's research community. 相似文献
60.
Hitchcock Daryl L.; Ammen Sue; O'Connor Kevin; Backman Toni L. 《Canadian Metallurgical Quarterly》2008,17(1):24
The authors investigated the reliability and construct validity of the Marschak Interaction Method Rating System (MIMRS), a new observational scoring system for the play-based Marschak Interaction Method (MIM), particularly its ability to capture high-risk parenting in adolescent mother-child dyads. The MIMRS demonstrated high interrater reliability and high internal consistency. Convergent validity was supported by moderately negative correlations between the MIMRS and the Parenting Stress Index/Short Form. The MIMRS demonstrated good contrasted groups validity, differentiating between 15 adolescent-child dyads and 16 adult- child comparison dyads, even after adjustment for differences in children's age. These results suggest that the MIMRS has the potential be a valuable rating system for research and practice with the MIM, as well as understanding and assessing parent-child relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献