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991.
Watkins SM Lin TY Davis RM Ching JR DePeters EJ Halpern GM Walzem RL German JB 《Lipids》2001,36(3):247-254
Diet and fatty acid metabolism interact in yet unknown ways to modulate membrane fatty acid composition and certain cellular
functions. For example, dietary precursors or metabolic products of n-3 fatty acid metabolism differ in their ability to modify
specific membrane components. In the present study, the effect of dietary 22∶6n−3 or its metabolic precursor, 18∶3n−3, on
the selective accumulation of 22∶6n−3 by heart was investigated. The mass and fatty acid compositions of individual phospholipids
(PL) in heart and liver were quantified in mice fed either 22∶6n−3 (from crocodile oil) or 18∶3n−3 (from soybean oil) for
13 wk. This study was conducted to determine if the selective accumulation of 22∶6n−3 in heart was due to the incorporation
of 22∶6n−3 into cardiolipin (CL), a PL most prevalent in heart and known to accumulate 22∶6n−3. Although heart was significantly
enriched with 22∶6n−3 relative to liver, the accumulation of 22∶6n−3 by CL in heart could not quantitatively account for this
difference. CL from heart did accumulate 22∶6n−3, but only in mice fed preformed 22∶6n−3. Diets rich in non-22∶6n−3 fatty
acids result in a fatty acid composition of phosphatidylcholine (PC) in heart that is unusually enriched with 22∶6n−3. In
this study, the mass of PC in heart was positively correlated with the enrichment of 22∶6n−3 into PC. The increased mass of
PC was coincident with a decrease in the mass of phosphatidylethanolamine, suggesting that 22∶6n−3 induced PC synthesis by
increasing phosphatidylethanolamine-N-methyltransferase activity in the heart. 相似文献
992.
993.
Social networking sites (SNS) have transformed how individuals interact, build and maintain social relationships. We proposed a research model on the determinants of user continuance using Bagozzi's framework of self-regulation as the theoretical foundation. Following the process of appraisal → emotional reactions → coping responses, we developed the model by leveraging findings from social presence and IS continuance research. Based on survey data from Facebook users, we found that appraisal factors (pleasure, awareness, connectedness, and system quality) were strong determinants of emotional reaction (user satisfaction and sense of belonging). User satisfaction and sense of belonging together positively influenced continuance intention. 相似文献
994.
It is well established in the psychology literature that personality predicts performance to some degree. However, personality neither solely nor directly predicts outcomes. Rather, performance and outcomes unfold through context-specific mediating constructs. This study identified two constructs that mediate the relationship between proactivity and perceived control of time in e-mail use and tested the model with data from 251 knowledge workers. The results show that proactivity predicts the perceived control of time in e-mail use through both e-mail-specific time management behavior and e-mail self-efficacy. Further, greater e-mail self-efficacy leads to improved e-mail-specific time management behavior. 相似文献
995.
In this paper, we develop a parallel algorithm for the solution of an integrated topology control and routing problem in Wireless Sensor Networks (WSNs). After presenting a mixed-integer linear optimization formulation for the problem, for its solution, we develop an effective parallel algorithm in a Master–Worker model that incorporates three parallelization strategies, namely low-level parallelism, domain decomposition, and multiple search (both cooperative and independent) in a single Master–Worker framework. 相似文献
996.
Cheng Hua Li Laurence T. Yang Man Lin 《International journal of parallel programming》2014,42(3):505-523
This paper studies parallel training of an improved neural network for text categorization. With the explosive growth on the amount of digital information available on the Internet, text categorization problem has become more and more important, especially when millions of mobile devices are now connecting to the Internet. Improved back-propagation neural network (IBPNN) is an efficient approach for classification problems which overcomes the limitations of traditional BPNN. In this paper, we utilize parallel computing to speedup the neural network training process of IBPNN. The parallel IBNPP algorithm for text categorization is implemented on a Sun Cluster with 34 nodes (processors). The communication time and speedup for the parallel IBPNN versus various number of nodes are studied. Experiments are conducted on various data sets and the results show that the parallel IBPNN together with SVD technique achieves fast computational speed and high text categorization correctness. 相似文献
997.
The paper is to introduce a new systematic method that can produce lower bounds for eigenvalues. The main idea is to use nonconforming finite element methods. The conclusion is that if local approximation properties of nonconforming finite element spaces are better than total errors (sums of global approximation errors and consistency errors) of nonconforming finite element methods, corresponding methods will produce lower bounds for eigenvalues. More precisely, under three conditions on continuity and approximation properties of nonconforming finite element spaces we analyze abstract error estimates of approximate eigenvalues and eigenfunctions. Subsequently, we propose one more condition and prove that it is sufficient to guarantee nonconforming finite element methods to produce lower bounds for eigenvalues of symmetric elliptic operators. We show that this condition hold for most low-order nonconforming finite elements in literature. In addition, this condition provides a guidance to modify known nonconforming elements in literature and to propose new nonconforming elements. In fact, we enrich locally the Crouzeix-Raviart element such that the new element satisfies the condition; we also propose a new nonconforming element for second order elliptic operators and prove that it will yield lower bounds for eigenvalues. Finally, we prove the saturation condition for most nonconforming elements. 相似文献
998.
999.
1000.
Lin Geng Jie Zhang Qing-Chang Meng Cong-Kai Yao 《Journal of the American Ceramic Society》2002,85(11):2864-2866
The side surfaces of a commercial β-SiC whisker were analyzed by calculating the surface energy and observing the microstructure of the whiskers. The results indicated that the side surfaces displayed a type of zigzag structure and were composed of {111}, {110}, and {100} crystal planes. 相似文献