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951.
Gamze Aydemir Yasamin Kasiri Eszter Birta Gabriella Béke Ada L. Garcia Emőke‐Márta Bartók Ralph Rühl 《Molecular nutrition & food research》2013,57(5):739-747
Dietary consumption of tomato products and especially the red tomato pigment lycopene has been associated with lower risk of cancer. New evidence is emerging toward metabolic pathways mediating the anti‐cancer activities of lycopene. In this review, we explore associations between tomatoes and lycopene intake and cancer and relate this to the metabolic activation pathways of lycopene via carotene oxygenases and further carotenoid/retinoid‐metabolizing enzymes to apo‐lycopenoids. Several of these apo‐lycopenoids have already been identified but up to date no direct connection between lycopene metabolism and apo‐lycopenoids mediated receptor activation pathways has been established. Retinoic acid receptors/retinoid‐X receptors activation pathways in particular, may be mediated via lycopene metabolites that are related to retinoic acids. Various studies have shown an association between lower concentration of insulin‐like growth factor‐1 upon lycopene treatment, cancer incidences, and retinoid‐mediated signaling. In this review, we interrelate tomato/lycopene ingestion and cancer incidence, with metabolic activation of lycopene and retinoid‐mediated signaling. The aim is to discuss a potential mechanism to explain lycopene related anti‐cancer activities by modulation of insulin‐like growth factor‐1 concentrations via lycopene metabolite activation of retinoid‐mediated signaling. 相似文献
952.
A bibliometric analysis of Spanish cardiovascular research is presented. The study focuses on the productivity, visibility and citation impact in an international, notably European context. Special attention is given to international collaboration. The underlying bibliographic data are collected from Thomson Reuters’s Web of Science on the basis of a ‘hybrid’ search strategy combining core journals, lexical terms and citation links especially developed for the field of cardiology. 相似文献
953.
954.
Flexible TDMA/WDMA passive optical network: Energy efficient next-generation optical access solution
Abhishek Dixit Bart Lannoo Goutam Das Didier Colle Mario Pickavet Piet Demeester 《Optical Switching and Networking》2013,10(4):491-506
Access networks must further advance to address the intensification of the requirements of growing speeds and the usage of Internet applications, and time and wavelength division multiple access (TDMA/WDMA) based passive optical networks (TWDM-PONs) have been widely considered as one of the evolutionary steps of next-generation optical access (NGOA) networks. TWDM-PON combines the flexibility of TDMA with an increased capacity offered by the use of a WDM layer. Moreover, it offers interesting and challenging avenues to minimize energy consumption: especially, with current access networks consuming about 80% of the energy consumed in the Internet. Along with other efforts, reducing energy consumption of central offices is conspicuous as it directly minimizes the operational expenditures of network providers. In this paper, we explore the new paradigms to conserve energy at the central offices in TWDM-PONs. By extensive simulations, we evaluate the possible energy savings in the various flavors of TWDM-PON. Based on the findings, we propose a new architectural flavor of TWDM-PON and benchmark the architecture for cost, power consumption and reach. We also propose a novel energy saving scheme for the proposed architecture and evaluate the impact of the proposed algorithm on energy savings by extensive simulations. 相似文献
955.
In an attempt to uncover intra-group behavior similarities, we developed an open multi-level framework for understanding the process of technology acceptance by its users. We partitioned our population into groups by clustering at several levels and then for each level it was divided into subgroups with a measurement layer added to uncover subgroup influence. Thus, by intersecting the resulting clusters of the set of models, the population was divided into subgroups that have similarities in the factors measured by the cluster layer models. Subsequently we tested our framework in a university hospital setting; personality and prior technology background models were used in clustering via the Five Factor Model and the Technology Readiness Index. UTAUT was used in the measurement layer. Our hypothesis that the subgroups have differing degrees of explained variance and different predictors was confirmed. Our framework was open, because any model that results in a taxonomy of the population can be used to obtain meaningful clusters. 相似文献
956.
Bart Saint Germain Paul Valckenaers Jan Van Belle Paul Verstraete Hendrik Van Brussel 《Journal of Intelligent Manufacturing》2012,23(6):2635-2646
This paper presents a decision-making pattern that uses trust mechanisms. It comprises an expectation module that performs two functions. First, it infers??based on past performance??how information is to be understood (e.g. consider the expected outcome of a promise to deliver tomorrow, morgen, ma?ana or domani). Second, it infers??based on past performance??the uncertainty on the expected behavior. This pattern makes a key contribution by enabling cooperation in large systems of systems without requiring conventional integration, which typically results in rigidity and monolithic system designs. It contributes to the development of holonic systems or nearly decomposable systems that deliver most of the advantages of integration without the disadvantages. 相似文献
957.
Dennis Bijlsma Miguel Alexandre Ferreira Bart Luijten Joost Visser 《Software Quality Journal》2012,20(2):265-285
We performed an empirical study of the relation between technical quality of software products and the issue resolution performance of their maintainers. In particular, we tested the hypothesis that ratings for source code maintainability, as employed by the Software Improvement Group (SIG) quality model, are correlated with ratings for issue resolution speed. We tested the hypothesis for issues of type defect and of type enhancement. This study revealed that all but one of the metrics of the SIG quality model show a significant positive correlation with the resolution speed of defects, enhancements, or both. 相似文献
958.
Bas de Geus Grégory Vandenbulcke Luc Int Panis Isabelle Thomas Bart Degraeuwe Elke Cumps Joris Aertsens Rudi Torfs Romain Meeusen 《Accident; analysis and prevention》2012
The purpose of this study is to gain insight into bicycle accidents. Bicycle accident data and weekly exposure data were prospectively collected for one year to calculate the incidence rate (IR) of bicycle accidents. An accident was included if it occurred during utilitarian cycling, resulting in an acute injury with corporal damage. If an accident occurred, a detailed questionnaire was filled out to collect detailed information about its circumstances and consequences. 相似文献
959.
The fundamental differences in hydrodynamics of the froth and spray regime account for the ongoing interest in search for the point of phase inversion. This short communication presents a new approach for identification of phase inversion on sieve trays in terms of an image-based measurement technique. Image analysis of entrained droplets reveals a distinct increase in Sauter mean diameter and droplet frequency during phase inversion. Further measurement methods like pressure drop, gravimetric analysis of entrained liquid, froth height assessment and photographic observation of the flow regime serve as a reference value and complement the discussion. A flow map based on the experimental data comprises each regime and shows a good agreement with phase inversion correlations from literature. 相似文献
960.