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排序方式: 共有191条查询结果,搜索用时 15 毫秒
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Alfaro Mde J Alvarez I El Khor S de Padilla FC 《Archivos latinoamericanos de nutrición》2004,54(2):223-228
The functional properties of Caryodendron orinocense protein product were investigated and compared with those of soybean (Glycina maxima). The product protein content was 24.47 g/100 g (Nx6.25). Solubility increased at both sides of the isoelectric point (pH 4.0) and with increased NaCl concentration up to 0.5M. Compared with soybean flour (50% protein), the protein product exhibited higher water and oil absorption, but lower emulsifying activity, emulsion stability, foaming capacity, and foam stability, the last one increase at higher pH. Emulsifying activity, foaming capacity, and foam stability were ionic strength dependent. C. orinocense protein product increased its emulsifying activity steadily from 0.05M to 0.75M NaCl, while it remained almost constant for soybean flour. Foaming capacity increased drastically at pH 10. The minimum time and concentration to form a gel was 20% in 4 min and 10% in 8 min for the Caryodendron protein product and soybean flour, respectively. The bulk density was 0.5056+/-0.0041 g/mL. 相似文献
3.
Eric Angel Evripidis Bampis Fanny Pascual Alex-Ariel Tchetgnia 《Journal of Scheduling》2009,12(5):437-445
We consider the problem of designing truthful mechanisms for scheduling n tasks on a set of m parallel related machines in order to minimize the makespan. In what follows, we consider that each task is owned by a selfish
agent. This is a variant of the KP-model introduced by Koutsoupias and Papadimitriou (Proc. of STACS 1999, pp. 404–413, 1999) (and of the CKN-model of Christodoulou et al. in Proc. of ICALP 2004, pp. 345–357, 2004) in which the agents cannot choose the machine on which their tasks will be executed. This is done by a centralized authority,
the scheduler. However, the agents may manipulate the scheduler by providing false information regarding the length of their
tasks. We introduce the notion of increasing algorithm and a simple reduction that transforms any increasing algorithm into
a truthful one. Furthermore, we show that some of the classical scheduling algorithms are indeed increasing: the LPT algorithm,
the PTAS of Graham (SIAM J. Appl. Math. 17(2):416–429, 1969) in the case of two machines, as well as a simple PTAS for the case of m machines, with m a fixed constant. Our results yield a randomized r(1+ε)-approximation algorithm where r is the ratio between the largest and the smallest speed of the related machines. Furthermore, by combining our approach with
the classical result of Shmoys et al. (SIAM J. Comput. 24(6):1313–1331, 1995), we obtain a randomized 2r(1+ε)-competitive algorithm. It has to be noticed that these results are obtained without payments, unlike most of the existing
works in the field of Mechanism Design. Finally, we show that if payments are allowed then our approach gives a (1+ε)-algorithm for the off-line case with related machines. 相似文献
4.
Kuan Wang Haoxiang Zhuo Jiantao Wang Fanny Poon Xueliang Sun Biwei Xiao 《Advanced functional materials》2023,33(13):2212607
Branded with low cost and a high degree of safety, with an ambitious aim of substituting lithium-ion batteries in many fields, sodium-ion batteries have received fervid attention in recent years after being dormant for decades. Layered materials are a major focus of study owing to the extensive experience already gained in lithium-ion batteries, and the pursuit of a Mn-rich composition is critical to reduce the cost while retaining the performance. This review provides a timely update of the recent progress of Mn-rich layered materials for sodium-ion batteries based on the understandings of the phase forming principles, structure transformation upon cycling and charge compensation mechanisms and discusses potential ambiguities in the pursuit of high-performance materials. 相似文献
5.
This study investigated the effectiveness, in terms of the attainment of relevant learning outcomes, of the types of learning promoted by educational features commonly incorporated in course management systems. Twenty-one courses with significant use of the Internet, but with face-to-face teaching as the predominant instructional mode, were investigated. Five hundred and ninety-five students taking these 21 courses completed a questionnaire which gave feedback on the extent of use of and quality of implementation of internet features, as well as their perception of the attainment of outcomes relating to approaches to learning, communication skills and understanding of content. A confirmatory factor analysis of scales pertinent to information presentation and constructive dialogue features showed a very poor fit to the data, indicating that the two types of function did not act in concert. Structural equation modelling was used to test instructional models in presage–process–product format for ‘information’ and ‘dialogue’ features. The information one showed a marginal fit to the data, but the dialogue one a very good fit. This shows that using the Internet for presenting information in a blended environment does not seem to effectively help students achieve learning outcomes. Using features which promote constructive dialogue and interactive learning activities encourages a deep approach to learning, the development of communication skills and enhanced understanding of content. 相似文献
6.
Anne Benoit Fanny Dufossé Alain Girault Yves Robert 《Journal of Parallel and Distributed Computing》2013
We consider pipelined real-time systems that consist of a chain of tasks executing on a distributed platform. The processing of the tasks is pipelined: each processor executes only one interval of consecutive tasks. We are interested in minimizing both the input–output latency and the period of application mapping. For dependability reasons, we are also interested in maximizing the reliability of the system. We therefore assign several processors to each interval of tasks, so as to increase the reliability of the system. Both processors and communication links are unreliable and subject to transient failures. We assume that the arrival of the failures follows a constant parameter Poisson law, and that the failures are statistically independent events. We study several variants of this multiprocessor mapping problem, with several hypotheses on the target platform (homogeneous/heterogeneous speeds and/or failure rates). We provide NP-hardness complexity results, and optimal mapping algorithms for polynomial problem instances. Efficient heuristics are presented to solve the general case, and experimental results are provided. 相似文献
7.
Fanny Lassalle Mickael Rosa Bart Staels Eric Van Belle Sophie Susen Annabelle Dupont 《International journal of molecular sciences》2022,23(10)
Transcatheter aortic valve replacement (TAVR), as an alternative to open heart surgery, has revolutionized the treatment of severe aortic valve stenosis (AVS), the most common valvular disorder in the elderly. AVS is now considered a form of atherosclerosis and, like the latter, partly of inflammatory origin. Patients with high-grade AVS have a highly disturbed blood flow associated with high levels of shear stress. The immediate reopening of the valve during TAVR leads to a sudden restoration of a normal blood flow hemodynamic. Despite its good prognosis for patients, TAVR remains associated with bleeding or thrombotic postprocedural complications, involving mechanisms that are still poorly understood. Many studies report the close link between blood coagulation and inflammation, termed thromboinflammation, including monocytes as a major actor. The TAVR procedure represents a unique opportunity to study the influence of shear stress on human monocytes, key mediators of inflammation and hemostasis processes. The purpose of this study was to conduct a review of the literature to provide a comprehensive overview of the impact of TAVR on monocyte phenotype and subset repartition and the association of these parameters with the clinical outcomes of patients with severe AVS who underwent TAVR. 相似文献
8.
9.
Rami Khazaka Etienne Moulin Mathieu Boccard Loïc Garcia Simon Hnni Franz‐Josef Haug Fanny Meillaud Christophe Ballif 《Progress in Photovoltaics: Research and Applications》2015,23(9):1182-1189
We compare the performance of two back reflector designs on the optoelectrical properties of microcrystalline silicon solar cells. The first one consists of a 5‐µm‐thick low‐pressure chemical vapor deposition (LPCVD)‐ZnO electrode combined with a white sheet; the second one incorporates an Ag reflector deposited on a thin LPCVD‐ZnO layer (with thickness below 200 nm). For this latter design, the optical loss in the nano‐rough Ag reflector can be strongly reduced by smoothing the surface of the thin underlying ZnO layer, by means of an Ar‐plasma treatment. Because of its superior lateral conductivity, the thin‐ZnO/Ag back reflector design provides a higher fill factor than the dielectric back reflector design. When decreasing the roughness of the front electrode with respect to our standard front LPCVD‐ZnO layer, the electrical cell performance is improved; in addition, the implementation of the thin‐ZnO/Ag back reflector leads to a significant relative gain in light trapping. Applying this newly optimized combination of front and back electrodes, the conversion efficiency is improved from 8.9% up to 9.4%, for cells with an active‐layer thickness of only 1.1 µm. We thereby highlight the necessity to optimize simultaneously the front and back electrodes. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
10.
Prabhakaran Thandapani Mangalaraja Ramalinga Viswanathan Marcus Vinícius-Araújo Andris F. Bakuzis Fanny Béron Arun Thirumurugan Juliano C. Denardin Jose A. Jiménez Ali Akbari-Fakhrabadi 《Journal of the American Ceramic Society》2020,103(9):5086-5097
The study demonstrates the performance of heating efficiency in single-phase and binary phase spinel ferrite nanosystems. Ferrimagnetic cobalt ferrite (CoFe2O4) (CFO) and superparamagnetic copper ferrite/copper oxide (CuFe2O4/CuO) (CuF) nanosystems of different particle sizes were synthesized through a microwave-assisted coprecipitation method. The heating behavior was observed in range of both field amplitudes (8-24 kA/m at 516 kHz) and frequencies (325-973 kHz at 12 kA/m). The heating efficiency was analyzed and compared by means of particle size, magnetization, effective anisotropy constant, and Néel relaxation mechanism. Indeed, the heating rate was maximized in larger ferrite particles with low effective anisotropy constant. Moreover, though the magnetization and effective anisotropy constant of single-phase CoFe2O4 nanoparticles were higher, the binary phase CuFe2O4/CuO nanosystems of similar crystallite size (28 nm) exhibited superior heating efficiency (4.21°C/s). For a field amplitude and frequency of 24 kA/m and 516 kHz, the heating rate of CuF and CFO ferrites with different crystallite sizes decreased in the order of 4.21 > 2.14 > 0.58 > 0.52°C/s for 29 nm > 25 nm > 12 nm > 15 nm, respectively. The results emphasize that binary phase ferrite nanoparticles are better thermoseeds than the single-phase ferrites for the magnetic hyperthermia application. 相似文献