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991.
Juan Morote Anna Celma Jacques Planas José Placer Inés de Torres Mireia Olivan Juan Carles Jaume Reventós Andreas Doll 《International journal of molecular sciences》2014,15(8):13615-13623
The aim of this study was to analyze the relationship between statin use along with serum cholesterol levels and prostate cancer (PCa) detection and aggressiveness. Statin users of three years or more and serum cholesterol levels (SC) were assessed in 2408 men scheduled for prostate biopsy. SC was classified as normal (NSC: <200 mg/dL) or high (HSC: >200 mg/dL). High-grade PCa (HGPCa) was considered if the Gleason score was greater than 7. Statin users comprised 30.9% of those studied. The PCa detection rate was 31.2% of men on statins and 37% of non-statin users (p < 0.006). The PCa detection rate was 26.3% in men with NSC and 40.6% in those with HSC (p < 0.001). In the subset of NSC men, the PCa rate was 26.5% for statin users and 26.2% for non-users (p = 0.939), while in men with HSC, the PCa rate was 36.4% for statin users and 42.0% for non-statin users (p = 0.063). The HGPCa rate was 41.8% for statin users and 32.5% for non-users (p = 0.012). NSC men had a 53.8% rate of HGPCa, while the rate was only 27.6% in HSC men (p < 0.001). NSC men on statins had an HGPCa rate of 70.2%, while non-statin users had a rate of 41.2% (p < 0.001). The HGPCa rate for HSC men on statins was 18.8%, while the rate was 30.0% (p = 0.011) for non-users. Logistic regression analysis suggested that serum cholesterol levels could serve as an independent predictor of PCa risk, OR 1.87 (95% CI 1.56–2.24) and HGPCa risk, OR 0.31 (95% CI 0.23–0.44), while statin usage could not. Statin treatment may prevent PCa detection through serum cholesterol-mediated mechanisms. A disturbing increase in the HGPCa rate was observed in statin users who normalized their serum cholesterol. 相似文献
992.
993.
A localized Delaunay triangulation owns the following interesting properties for sensor and wireless ad hoc networks: it can
be built with localized information, the communication cost imposed by control information is limited, and it supports geographical
routing algorithms that offer guaranteed convergence. This paper presents two localized algorithms, fast localized Delaunay
triangulation 1 (FLDT1) and fast localized Delaunay triangulation 2 (FLDT2), that build a graph called planar localized Delaunay
triangulation, PLDel, known to be a good spanner of the Unit Disk Graph, UDG. Our algorithms improve previous algorithms with similar theoretical bounds in the following aspects: unlike previous work,
FLDT1 and FLDT2 build PLDel in a single communication step, maintaining a communication cost of O(n log n), which is within a constant of the optimal. Additionally, we show that FLDT1 is more robust than previous triangulation
algorithms, because it does not require the strict UDG connectivity model to work. The small signaling cost of our algorithms allows us to improve routing performance, by efficiently
using the PLDel graph instead of sparser graphs, like the Gabriel or the Relative Neighborhood graphs. 相似文献
994.
Daniel Castro-Lacouture Jorge A. Sefair Laura Flórez Andrés L. Medaglia 《Building and Environment》2009
Buildings have a significant and continuously increasing impact on the environment because they are responsible for a large portion of carbon emissions and use a considerable number of resources and energy. The green building movement emerged to mitigate these effects and to improve the building construction process. This paradigm shift should bring significant environmental, economic, financial, and social benefits. However, to realize such benefits, efforts are required not only in the selection of appropriate technologies but also in the choice of proper materials. Selecting inappropriate materials can be expensive, but more importantly, it may preclude the achievement of the desired environmental goals. In order to help decision-makers with the selection of the right materials, this study proposes a mixed integer optimization model that incorporates design and budget constraints while maximizing the number of credits reached under the Leadership in Energy and Environmental Design (LEED) rating system. To illustrate this model, this paper presents a case study of a building in Colombia in which a modified version of LEED is proposed. 相似文献
995.
Aguiar Javier M. Baladrón Carlos De La Cuesta Borja Ordás Arnal Isabel Mignot Patrice Carrozzo Gino Comi Paolo 《IEEE network》2009,23(6):43-49
This article presents a new end-to-end architecture model that will enable the deployment of a plethora of different multimedia services from diverse suppliers competitively coexisting over a common access and home networking environment. The model is focused on personal multimedia communication services and terminals. The proposed model is a segmentation of the end-to-end multimedia chain into several business segments. The interfaces among segments and functional entities inside each segment are identified and defined in the work. In order to study the impact level of the results achieved, a comparison with the approximation to NGN provided by current standardization bodies in the field (3GPP and TISPAN) is also included in the article. This comparison highlights the advantages of using this model as a solution to offer PMC services. 相似文献
996.
David Gatineau Jean-Philippe Goddard Virginie Mouriès-Mansuy Louis Fensterbank 《Israel journal of chemistry》2013,53(11-12):892-900
Thanks to their unique electronic and steric properties, carbene ligands offer highly valuable features for catalysis, including homogenous gold catalysis. The use of carbene-gold complexes has improved existing reactions, either by modifying reactivity modes or by leading to highly asymmetric processes. These topics will be discussed on the basis of selected examples. 相似文献
997.
M. Sahli C. Millot J.-C. Gelin T. Barrière 《Journal of Materials Processing Technology》2013,213(6):913-925
In this paper, the manufacturing of metallic microfluidic mould inserts is studied based on the hot embossing process. The feedstocks are prepared and analysed. The quality of the feedstock resulting from the mixing process is found to depend on numerous parameters, such as the mixing time, the mixing temperature, the shear rate and the powder loading. The present mixing study is conducted with copper powders. The thermal and rheological properties of the selected feedstock under various mixing conditions are determined and used to establish the necessary conditions for mixing, hot embossing and debinding to obtain the copper microfluidic mould inserts. Sintering at different temperatures is conducted under vacuum. The effects of the sintering temperatures are evaluated based on the sintered microstructures. In this work, the dimensional variations in the microfluidic samples, in particular the dimensional shrinkage, global warpage and surface roughness at each stage of the process, are quantified and compared in detail. 相似文献
998.
999.
1000.
M. ?itnik M. Kav?i? B. Paripás K. T?kési 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(2):260-262
We present an experimental study of L-MM resonant Auger spectra of argon after electron impact excitation. The electron spectra were measured at ten different electron impact energies between 442.6 eV and 461.7 eV. During (e, 2e) measurement the energy of the second electron was kept fixed at 209.6 eV, corresponding to the energy of one of the strongest resonant Auger transitions from the [2p3/23d] state. Except for the monopole excitations, the recorded spectral structures are explained on the basis of photon impact data. 相似文献