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排序方式: 共有825条查询结果,搜索用时 781 毫秒
51.
Marion MORENA Bernard CANAUD Nathalie TERRIER Ludovic CANAUD Jean‐Paul CRISTOL 《Hemodialysis international. International Symposium on Home Hemodialysis》2007,11(Z1):S32-S38
Patients undergoing maintenance hemodialysis (HD) have a high prevalence of protein‐energy malnutrition and inflammation. As these 2 conditions often occur concomitantly in HD patients, they have been referred to together as the ‘malnutrition‐inflammation complex syndrome’ (MICS) or ‘malnutrition‐inflammation atherosclerosis’ (MIA) syndrome to emphasize its important association with atherosclerotic cardiovascular disease. Oxidative stress, which results from an imbalance between oxidants and antioxidant defense mechanisms, is well established in HD subjects and could contribute to the poor clinical outcome of these patients. The aim of the present review is to discuss in more detail the common consequences of MICS and oxidative stress and their possible relationships with the long‐term complications of HD patients, leading to the conclusion that a complex syndrome similar to the MICS or MIA is the oxidative stress‐inflammation association, which may be called the “oxidative stress complex syndrome.” 相似文献
52.
Sohee Lee Marion Leibold Martin Buss Frank Chongwoo Park 《Advanced Robotics》2013,27(11-12):1317-1341
We present a rollover prevention control law for wheeled mobile manipulators based on the invariance control framework, and that makes use of recursively calculated analytic gradients of the mobile manipulator’s zero moment point. Our controller relaxes many of the assumptions made in existing approaches, and enhances robustness through the use of exact gradient information. Numerical experiments demonstrate the improved performance of our controller vis-à-vis existing rollover prevention schemes. 相似文献
53.
Marion Gabarrou Daniel Alazard Dominikus Noll 《Mathematics of Control, Signals, and Systems (MCSS)》2013,25(2):257-290
We design a feedback control architecture for longitudinal flight of an aircraft. The multi-level architecture includes the flight control loop to govern the short-term dynamics of the aircraft, and the autopilot to control the long-term modes. Using $H_\infty $ performance and robustness criteria, the problem is cast as a non-convex and non-smooth optimization program. We present a non-convex bundle method, prove its convergence, and show that it is apt to solve the longitudinal flight control problem. 相似文献
54.
Iman Shahosseini Elie Lefeuvre Johan Moulin Marion Woytasik Emile Martincic Gaël Pillonnet Guy Lemarquand 《Microsystem Technologies》2013,19(6):879-886
This work presents the conception, the microfabrication, and the electroacoustic characterization of a new electromagnetic microspeaker based on silicon. The objectives are to get improved sound quality compared to that of conventional microspeakers, while keeping the electroacoustic efficiency as high as possible. An optimized stiffening silicon microstructure let the sound radiator be extremely light and rigid. The mobile part is suspended to the fixed part by silicon suspension springs, which enable large out-of-plane displacement. The acoustic radiator is actuated by an electromagnetic motor, composed of a fixed permanent magnet and a planar coil located on top of the silicon radiator. The piston-like motion of the radiator favored by this structure is very beneficial for the sound quality. Electro–mechano–acoustic characterization of the microfabricated microspeaker showed that the radiator surface could run out-of-plane with displacements higher than ±400 μm, with no mechanical and electrical failure. For an electrical power of 0.5 W, the microspeaker was capable to generate a sound pressure level of 80 dB at 10 cm, from 330 Hz up to 20 kHz frequency. The efficiency reaches 3 × 10?5, that is to say three times more than typical efficiency of conventional microspeakers. Moreover, as characterization results showed, the existence of very few structural modes and the low electroacoustic distortions evidence the high sound quality of the microspeaker. 相似文献
55.
Design of LTCC with High Thermal Expansion 总被引:1,自引:0,他引:1
Markus Eberstein Carsten Glitzky Marion Gemeinert Torsten Rabe Wolfgang A. Schiller Christina Modes 《International Journal of Applied Ceramic Technology》2009,6(1):1-8
New applications of low-temperature co-fired ceramics (LTCC), such as pressure sensors or integrated functional layers, require materials that possess higher coefficients of thermal expansion (CTE). To fabricate LTCC with elevated CTE, two methods of material design are examined: firstly, glass ceramic composites (GCC), which consist of >50 vol% glass in the starting powder, and, secondly, glass-bonded ceramics (GBC), where glass is added as a sintering aid only. The CTE of GBC is mainly determined by the crystalline component. For GCC, the CTE can be well predicted, if CTE and elastic data of each phase in the microstructure are known. A nonlinear characteristic of the CTE versus phase composition was found with increasing E crystals / E glass ratio and absolute CTE difference between the components. The glass composition and glass amount can be used to compensate the fixed properties of a crystalline material in a desired way. However, because the CTE and permittivity of a glass cannot be chosen independently, an optimum glass composition has to be found. For a given LTCC, it is possible to control the devitrification by shifting the glass composition. In this way, the resulting CTE values can be predicted more exactly and tailoring becomes possible. Different LTCC materials, based on the crystalline compounds Ba(La,Nd)2 Ti4 O12 , ZrO2 (Y-TZP), SiO2 (quartz), and specially developed glasses, possessing an elevated CTE of around 10 × 10−6 K−1 while showing permittivity ɛr between 6 and 63, are introduced. 相似文献
56.
57.
This randomized experimental prevention study (a) evaluated the effectiveness of a parent-training program in a sample of 238 divorcing mothers with sons in Grades 1–3 and (b) provided an experimental test of coercion theory. The intervention produced reductions in observed coercive parenting, prevented decay in positive parenting, and generally improved effective parenting practices in comparisons of mothers in experimental and control groups. Moreover, coercion theory was supported. Improved parenting practices correlated significantly with improvements in teacher-reported school adjustment, child-reported maladjustment, and mother-reported maladjustment. The intervention indirectly benefitted child outcomes through improved parenting practices for a model based on child report and, to a lesser extent, on teacher report. The intervention did not produce direct effects on child outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
59.
Recent epidemiology studies examining U.S. recreational water exposure and illness relationships have focused primarily on coastal and Great Lakes beaches. Human-made lakes in the U.S. have received little attention in epidemiology studies despite contributing to more waterborne disease epidemics annually than coastal U.S. waters. In a comprehensive beach cohort study, we examined relationships between water quality indicators and reported adverse health outcomes among users of a beach at an inland U.S. lake. Human health data was collected over 26 swimming days during the 2009 swimming season in conjunction with water quality measurements. Adverse health outcomes were reported 8-9 days post-exposure via a phone survey. Wading, playing or swimming in the water was observed to be a significant risk factor for GI illness (adjusted odds ratio (AOR) of 3.2; CI 1.1, 9.0). Among water users, Escherichia coli density was significantly associated with elevated GI illness risk where the highest E. coli quartile was associated with an AOR of 7.0 (CI 1.5, 32). GI illness associations are consistent with previous freshwater epidemiology studies. Our findings are unique in that our observations of positive associations with GI illness risk are based upon a single daily E. coli measurement. Lastly, this study focused on an understudied issue, illness risk at inland reservoirs. Our results support the usefulness of E. coli as a health-relevant indicator of water quality for this inland U.S. beach. 相似文献
60.
Marion Graf Manuel Thesen Hartmut Krüger Peter Mayer Karlheinz Sünkel 《Inorganic chemistry communications》2009,12(8):701-703
The synthesis of the bis-cyclometalated complex [{Ir(μ-Cl)(ccpz)2}2] (1, cppz = 1-chloro-4-(4-chlorophenyl)-phthalazine) from hydrated iridium(III) chloride and the ligand ccpz in refluxing ethoxyethanol is described. Compound 1 was characterized by spectroscopic means and the crystal structure was determined by X-ray crystallography. The absorption and emission spectra exhibit the new compound as a red-emitting phosphorescent complex. 相似文献