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Distributed Coordination and Workflow on the World Wide Web   总被引:5,自引:0,他引:5  
This paper describes WebFlow, an environment thatsupports distributed coordination services on theWorld Wide Web. WebFlow leverages the HTTP Webtransport protocol and consists of a number of toolsfor the development of applications that require thecoordination of multiple, distributed servers.Typical applications of WebFlow include distributeddocument workspaces, inter/intra-enterprise workflow,and electronic commerce. In this paper we describe thegeneral WebFlow architecture for distributedcoordination, and then focus on the environment fordistributed workflow.  相似文献   
3.
Waveguiding through a two-dimensional metallic photonic crystal   总被引:1,自引:0,他引:1  
We present a two‐dimensional (2D) finite‐difference time domain simulation of the propagation of light through linear and bent channels in metallic photonic crystals. We took as a starting point the Bozhevolnyi experiment, consisting of the scattering of surface plasmons by a 2D structure of finitely sized periodic gold dots arranged in a triangular lattice of 400‐nm period. We model injection and propagation of light through linear channels of different widths. We also study the behaviour of light in the presence of a 90° bent line defect made in the structure. We show that the confinement depends on the orientation of the input and output line defects. The two cases of ΓM and ΓK orientations are considered and a spectral study for five different wavelengths is carried out.  相似文献   
4.
Social media has experienced rapid growth in recent years and has been subjected of discussions on a wide range of topics including new lifestyles and eating habits, providing a great opportunity to obtain spontaneous consumer information. In this sense, the present work aimed to understand the perception of Twitter® users about themes of veganism and plant-based diets. The social networking data mining methodology was applied to measure the relationship between both terms. The significant differences found were analysed using the global chi-square (χ2) test, and their sources of variation were investigated by the chi-square per cell. The results indicate that the vegan group's posts are more related to the categories of recipes, trends, criticism and negative comments about veganism, being more often citing sources when compared to the other group. The results of the plant-based diet group are more significantly related to the impacts of nutrition, physical activity and consumer health. In conclusion, Twitter® has proved to be an interesting tool for obtaining data on (re) produced food publications on social media and their results can guide the market and the academic environment in creating new products, services and marketing strategies to answer the needs of specific consumers.  相似文献   
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In addition to CD4+ T lymphocytes, myeloid cells and, particularly, differentiated macrophages are targets of human immunodeficiency virus type-1 (HIV-1) infection via the interaction of gp120Env with CD4 and CCR5 or CXCR4. Both T cells and macrophages support virus replication, although with substantial differences. In contrast to activated CD4+ T lymphocytes, HIV-1 replication in macrophages occurs in nondividing cells and it is characterized by the virtual absence of cytopathicity both in vitro and in vivo. These general features should be considered in evaluating the role of cell-associated restriction factors aiming at preventing or curtailing virus replication in macrophages and T cells, particularly in the context of designing strategies to tackle the viral reservoir in infected individuals receiving combination antiretroviral therapy. In this regard, we will here also discuss a model of reversible HIV-1 latency in primary human macrophages and the role of host factors determining the restriction or reactivation of virus replication in these cells.  相似文献   
7.
Liquipron and Toprina, obtained by growing yeasts (Candida maltosa and Candida lipolytica) on n-hydrocarbons, were investigated to ascertain the biological significance and possible toxicological implications of their high content of uneven fatty acids (UFA). It was confirmed that the extent to which UFA accumulate in adipose tissue of rats fed the 2 products reflects only partially their UFA contents. The presence of UFA in rat tissues does not appear to alter intermediate metabolism. The capacity of liver mitochondria ot oxidize palmitic acid was similar in control and in Liquipron-treated rats. Palmitic acid and heptadecanoic acid did not compete for oxidation when mixed at concentrations which reflect their presence in the tissues of animals fed high levels of Liquipron.  相似文献   
8.
The paper contains the first complete proof of strong normalization (SN) for full second order linear logic (LL): Girard’s original proof uses a standardization theorem which is not proven. We introduce sliced pure structures (sps), a very general version of Girard’s proof-nets, and we apply to sps Gandy’s method to infer SN from weak normalization (WN). We prove a standardization theorem for sps: if WN without erasing steps holds for an sps, then it enjoys SN. A key step in our proof of standardization is a confluence theorem for sps obtained by using only a very weak form of correctness, namely acyclicity slice by slice. We conclude by showing how standardization for sps allows to prove SN of LL, using as usual Girard’s reducibility candidates.  相似文献   
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Adjuvant chemotherapy-induced amenorrhoea has been shown to be associated with reduced relapses and improved survival for premenopausal breast cancer patients. Amenorrhoea was, therefore, studied to define features of chemotherapy (i.e. duration and timing) and disease-related factors which are associated with its treatment effects. We reviewed data from IBCSG Trial VI, in which accrual was between July 1986 and April 1993. 1196 of the 1475 eligible patients (81%) were evaluable for this analysis. The median follow-up was 60 months. Women who experienced amenorrhoea had a significantly better disease-free survival (DFS) than those who did not (P = 0.0004), although the magnitude of the effect was reduced when adjusted for other prognostic factors (P = 0.09). The largest treatment effect associated with amenorrhoea was seen in patients assigned to receive only three initial CMF courses (5-yr DFS: 67% versus 49%, no amenorrhoea; hazard ratio, 0.55; 95% confidence interval, 0.38 to 0.81; P = 0.002). DFS differences between amenorrhoea categories were larger for patients with ER/PR positive tumours (hazard ratio, 0.65; 95% confidence interval, 0.53 to 0.80; P = 0.0001). Furthermore, patients whose menses returned after brief amenorrhoea had a DFS similar to those whose menses ceased and did not recover (hazard ratio, 1.10; 95% confidence interval, 0.75 to 1.62; P = 0.63). The effects associated with a permanent or temporary chemotherapy-induced amenorrhoea are especially significant for node-positive breast cancer patients who receive a suboptimal duration of CMF chemotherapy. Cessation of menses, even for a limited time period after diagnosis of breast cancer, might be beneficial and should be prospectively investigated, especially in patients with oestrogen receptor-positive primaries.  相似文献   
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