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101.
Fiona Polack 《Software》2001,31(8):757-780
This paper presents an approach using derivation of a formal model to review the diagram‐and‐text specification of an information system specification, based on concepts from the formal and structured integrated method, SAZ. Extraction of the formal model is outlined, and the approach is illustrated with a simplified extract from an industrial trial. Some empirical findings from the trial, which reviewed a pre‐existing commercial specification, are presented, and the general applicability of the review approach is discussed. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
102.
The synthesis of two new 4,4′ bisoxazoline ligands is described. The use of copper complexes of these and three other recently described related ligands as catalysts in a cyclopropanation reaction is discussed. The first structural data on one such chiral copper complex is reported herein.  相似文献   
103.
104.
Health information tailored to meet individuals' unique needs has been shown to be more effective than generic information in promoting risk-reducing behavior changes. To explore mechanisms underlying tailoring's effectiveness, this study randomly assigned 198 overweight adults to receive weight-loss materials that were either (a) tailored to the individual, (b) in an American Heart Association (AHA) brochure, or (c) AHA-content formatted to look like tailored materials. Participants who received tailored materials had more positive thoughts about the materials, positive personal connections to the materials, positive self-assessment thoughts, and positive thoughts indicating behavioral intention than those who received either of the untailored materials. The tailoring of health information can significantly improve the chances the information will be thoughtfully considered and can stimulate prebehavioral changes such as self-assessment and intention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
105.
We have studied the mechanical and morphological properties of carbon nanotube films prepared from tubes produced by a range of commercial suppliers. We find significant correlations between mechanical parameters (modulus, strength, toughness and ductility) and morphological parameters (porosity and bundle diameter). Both strength and toughness scale linearly with the number of inter-bundle junctions per unit volume as calculated from the porosity and bundle size. Applying a simple model, we can use this data to find the average force and energy required to break a junction to be ∼113 pN and 0.7 eV, respectively. This latter value agrees well with the value of 0.9 eV estimated from the nanotube surface energy, indicating that adjacent bundles are bound predominately by van der Waals interactions.  相似文献   
106.
107.
Both type 1 and type 2 diabetes are characterized by a progressive loss of beta cell mass that contributes to impaired glucose homeostasis. Although an optimal treatment option would be to simply replace the lost cells, it is now well established that unlike many other organs, the adult pancreas has limited regenerative potential. For this reason, significant research efforts are focusing on methods to induce beta cell proliferation (replication of existing beta cells), promote beta cell formation from alternative endogenous cell sources (neogenesis), and/or generate beta cells from pluripotent stem cells. In this article, we will review (i) endogenous mechanisms of beta cell regeneration during steady state, stress and disease; (ii) efforts to stimulate endogenous regeneration and transdifferentiation; and (iii) exogenous methods of beta cell generation and transplantation.  相似文献   
108.
OPUS的挂钩     
Fiona 《建筑知识》2011,(8):88-89
OPUS是一个专门从事手袋挂钩的品牌。那些挂钩可以安全地摆在桌角,用于悬挂手袋。即不占桌椅的空间,又可以解放双手去做其事情。位于台北的OPUS是其品牌全球唯一的一家实体经营店,店面是由台北本土的年轻团队Paradox Studio担任设计。空间围绕这"多功能性"展开,既可用于会议,也可像零售店一样出售产品。  相似文献   
109.
110.
In ongoing studies towards novel hepatitis C virus (HCV) therapeutics, inhibitors of nonstructural protein 5A (NS5A) were evaluated. Specifically, starting from previously reported lead compounds, peripheral substitution patterns of a series of biaryl‐linked pyrrolidine NS5A replication complex inhibitors were probed and structure–activity relationships were elucidated. Using molecular modelling and a supercritical fluid chromatographic (SFC) technique, intramolecular H‐bonding and peripheral functional group topology were evaluated as key determinants of activity and membrane permeability. The novel compounds exhibited retained potency as compared with the lead compounds, and also showed promising results against a panel of resistance viruses. Together, the results of the study take us a step closer towards understanding the potency of daclatasvir, a clinical candidate upon which the compounds were based, and to designing improved analogues as second‐generation antiviral agents targeting NS5A.  相似文献   
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