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71.
72.
Precision oncology is an emerging approach in cancer care. It aims at selecting the optimal therapy for the right patient by considering each patient’s unique disease and individual health status. In the last years, it has become evident that breast cancer is an extremely heterogeneous disease, and therefore, patients need to be appropriately stratified to maximize survival and quality of life. Gene-expression tools have already positively assisted clinical decision making by estimating the risk of recurrence and the potential benefit from adjuvant chemotherapy. However, these approaches need refinement to further reduce the proportion of patients potentially exposed to unnecessary chemotherapy. Nuclear magnetic resonance (NMR) metabolomics has demonstrated to be an optimal approach for cancer research and has provided significant results in BC, in particular for prognostic and stratification purposes. In this review, we give an update on the status of NMR-based metabolomic studies for the biochemical characterization and stratification of breast cancer patients using different biospecimens (breast tissue, blood serum/plasma, and urine).  相似文献   
73.
Because previous literature reports have demonstrated that nucleated trout erythrocytes in conditions of oxidative stress are subjected to both membrane damage and a decrease in the enzymatic defense systems (glutathione peroxidase), which in turn lead to hemolysis, the present study was undertaken to determine whether DNA may be affected too, prior to the hemolytic event. Impairment of DNA in stressed trout erythrocytes was assessed using the comet assay--a rapid and sensitive, single-cell gel electrophoresis technique used to detect primary DNA damage in individual cells. In addition, indolinic and quinolinic nitroxide radicals were included in the study to determine their efficacy as antioxidants against free-radical-induced DNA damage. The parameters, tail length, tail intensity, and tail moment, used as an index of DNA damage, have shown that trout erythrocytes exposed to oxidative stress experience DNA damage prior to hemolysis and that the nitroxides significantly prevent this damage. This result provides further information about the potential use of these compounds as antioxidants in biological systems.  相似文献   
74.
This paper focuses on ambient assisted living systems employed to monitor the ongoing situations of elderly people living independently. Such situations are represented here as contexts inferred by multiple software agents out of the data gathered from sensors within a home. Sensors can give an incomplete, sometimes ambiguous, picture of the world; hence, they often lead to inconsistent contexts and unreliability on the system as a whole. We report on a solution to this problem based on a multi-agent system where each agent is able to support its understanding of the context through arguments. These arguments can then be compared against each other to determine which agent provides the most reliable interpretation of the reality under observation.  相似文献   
75.
Temperature increase and the effects of greenhouse gases are among the most important issues associated with climate change. Studies have shown that the production and quality of fresh fruit and vegetable crops can be directly and indirectly affected by high temperatures and exposure to elevated levels of carbon dioxide and ozone. Temperature increase affects photosynthesis directly, causing alterations in sugars, organic acids, and flavonoids contents, firmness and antioxidant activity. Carbon dioxide accumulation in the atmosphere has directly effects on postharvest quality causing tuber malformation, occurrence of common scab, and changes in reducing sugars contents on potatoes. High concentrations of atmospheric ozone can potentially cause reduction in the photosynthetic process, growth and biomass accumulation. Ozone-enriched atmospheres increased vitamin C content and decreased emissions of volatile esters on strawberries. Tomatoes exposed to ozone concentrations ranging from 0.005 to 1.0 μmol/mol had a transient increase in β-carotene, lutein and lycopene contents.  相似文献   
76.
77.
Traditional distributed filesystem technologies designed for local and campus area networks do not adapt well to wide area Grid computing environments. To address this problem, we have designed the Chirp distributed filesystem, which is designed from the ground up to meet the needs of Grid computing. Chirp is easily deployed without special privileges, provides strong and flexible security mechanisms, tunable consistency semantics, and clustering to increase capacity and throughput. We demonstrate that many of these features also provide order-of-magnitude performance increases over wide area networks. We describe three applications in bioinformatics, biometrics, and gamma ray physics that each employ Chirp to attack large scale data intensive problems.  相似文献   
78.
Gabe Moretti 《电子设计技术》2005,12(6):48-48,50,52-53
以自然语言编写的产品规范的含糊其辞,常常会带来设计缺陷,而这种缺陷直到较晚阶段才会被发现,从而使解决方案变得更加昂贵。  相似文献   
79.
We report two studies aimed at investigating the effects of distinct negative emotions on pairwise economic interactions. In the ultimatum game, a proposer offers a division of a sum of money to a responder who decides whether to accept the split, or reject and leave both players with nothing. In Experiment 1, we investigated whether induced disgust, as compared to sadness and neutral emotion, specifically influences responders' decisions to reject unfair proposals. In Experiment 2, we assessed whether the effects of disgust were selectively related to social contexts by contrasting interactions with a human partner with those involving a computer. Results showed that relative to being in a sad or neutral mood, induced feelings of disgust significantly increased rejection rates of unfair offers. Moreover, we found that when the partner was not responsible for the fairness violation, such as in the computer-offer condition, the disgust induction failed to affect participants' choices. We conclude by focusing on the hypothesis that disgust and social norm violations may share common computational components, both at a psychological and a neural level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
80.
In component-based development, software components are taken as units of composition. Nevertheless, to achieve the widely disseminated status of components being plugged together as simple ‘Lego Pieces’, the integration of components must be carefully designed, systematised and verified; only this can ensure reliable architectures. In this work, we propose some conformance notions to predict the precise nature of some forms of composition, considering coordination patterns used in the integration. These notions are formalised in terms of the denotational semantics of the process algebra CSP, and assist the designer in common activities during integration, such as the substitution of component specifications by implementations, contract adaptations, and system extensions. To support mechanical verifications using FDR (a model-checker for CSP), we derive test characterisations from the denotational definitions of conformance. We illustrate the application of these notions through a systematic composition strategy of software frameworks, and we mechanically verify the preservation of behavioural component properties in these compositions. Moreover, we characterise the well-formedness of a coordination pattern used in this strategy at the design stage, before components are assembled.  相似文献   
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