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21.
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   
22.
Behavioural models for distributed Fractal components   总被引:2,自引:0,他引:2  
This paper presents a formal behavioural specification framework for specifying and verifying the correct behaviour of distributed Fractal components. The first contribution is a parameterised and hierarchical behavioural model called pNets that serves as a low-level semantic framework for expressing the behaviour of various classes of distributed languages and as a common internal format for our tools. Then, we use this model to define the generation of behavioural models for applications ranging from sequential Fractal components, to distributed objects, and finally to distributed components. Our models are able to characterise both functional and non-functional behaviours and the interaction between the two concerns. Finally, this work has resulted in the development of tools allowing the non-expert programmer to specify the behaviour of his components and (semi)automatically verify properties of his application.  相似文献   
23.
We have studied how spherical 23 ± 3 nm Au(45)Ag(55) nanoparticles embedded within a silica matrix transform into prolate nanorods and nanowires by irradiating them with swift heavy ions. Samples were irradiated at room temperature and normal incidence with 74 MeV Kr and 36 MeV S ions for fluences up to 1.0 × 10(15) cm(-2). We demonstrate the existence of two regimes: (i) below a critical fluence, ~ 2.0 × 10(14) cm(-2), the transformation of the spherical nanoparticle into a nanorod is an individual process, i.e. each nanoparticle transforms into a single nanorod; (ii) for larger fluences the transformation from nanorod to nanowire becomes a collective process, i.e. the break up and dissolution of unstable nanorods contribute to the growth of long nanowires. The passage from the first to the second regime can be interpreted in terms of a Rayleigh-like instability under irradiation. The latter becomes active when the diameter of the nanowire approaches its saturation width under irradiation. Furthermore, we show that the composition of the alloy is only slightly modified during the ion-shaping process. Finally, the energy and the fluence thresholds for deformation and the deformation strain-rate are estimated.  相似文献   
24.
Aminophenoxazinone dyes with variable water solubilities were assayed for the first time in a live‐cell imaging application. Among a library of ten sulfonylated chromophores, one compound gave excellent results as an endocytic marker, showing a precise subcellular distribution. The compound was compared to four commercial vital tracers, including Lucifer Yellow. The first laccase‐mediated regioselective synthesis of a diphosphorylated 2‐aminophenoxazinone dye was also described. This compound, water‐soluble at 10?2 M , displayed modest fluorescence properties and the ability to complex Mg2+ and Ca2+ cations, therefore giving fluorescence quenching.  相似文献   
25.
The role of phonology-to-spelling consistency (i.e., feedback consistency) was investigated in 3 lexical decision experiments in both the visual and auditory modalities in French and English. No evidence for a feedback consistency effect was found in the visual modality, either in English or in French, despite the fact that consistency was manipulated for different kinds of units (onsets and rimes). In contrast, robust feedback consistency effects were obtained in the auditory lexical decision task in both English and French when exactly the same items that produced a null effect in the visual modality were used. Neural network simulations are presented to show that previous demonstrations of feedback consistency effects in the visual modality can be simulated with a model that is not sensitive to feedback consistency, suggesting that these effects might have come from various confounds. These simulations, together with the authors' results, suggest that there are no feedback consistency effects in the visual modality. In contrast, such effects are clearly present in the auditory modality. Given that orthographic information is absent from current models of spoken word recognition, the present findings present a major challenge to these models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
26.
Texture mapping is a method commonly used to increase the visual complexity of computer generated images while maintaining simplicity in the underlying geometric models. Texture maps are generally defined in two dimensional space; thus, a primary problem when applying textures to objects is determining a mapping transformation from the three dimensional space of the object to the two dimensional space of the map. A method for mapping complex polygonal geometries is presented. The algorithmunfolds the object polygon by polygon and projects the texture map onto the resulting two dimensional geometry. Enhancements to the basic unfolding algorithm either (1) control the location of map distorition introduced at areas of severe curvature or (2) average distortions over a larger area.  相似文献   
27.
The assessment of the glycemic index (GI) seems to be an important parameter to take into account in order to better understand the physiologic effects of foods with high carbohydrate levels. Among cereals, which are major sources of carbohydrates, spelt (Triticum spelta L.) has been considered as particularly interesting from a nutritional point of view. The aim of this study was to evaluate in vivo the GI of white spelt bread in healthy subjects. The wheat (Triticum aestivum L.) white bread was used as reference food. To avoid differences in the production of both breads, spelt and wheat breads were baked under the same controlled conditions. Results showed that the glycemic profile of spelt white bread was not different from that of wheat white bread (GI of 93 ± 9). The area under the glycemic curve significantly and negatively correlated to fasting glycemia and carbohydrate intake during evening meals preceding the test. In conclusion, the glycemic response to spelt bread was similar to that of wheat bread. However, in order to avoid more inter-individual variability, our data supports the importance to propose standardised carbohydrate content for the last meal before evaluating the GI of food.  相似文献   
28.
The effect of gate-length variation on DC and RF performance of InAs/AlSb HEMTs, biased for low DC power consumption or high gain, is reported. Simultaneously fabricated devices, with gate lengths between 225 nm and 335 nm, have been compared. DC measurements revealed higher output conductance gds and slightly increased impact ionization with reduced gate length. When reducing the gate length from 335 nm to 225 nm, the DC power consumption was reduced by approximately 80% at an fT of 120 GHz. Furthermore, a 225 nm gate-length HEMT biased for high gain exhibited an extrinsic fT of 165 GHz and an extrinsic fmax of 115 GHz, at a DC power consumption of 100 mW/mm. When biased for low DC power consumption of 20 mW/mm the same HEMT exhibited an extrinsic fT and fmax of 120 GHz and 110 GHz, respectively.  相似文献   
29.
Herein we describe the synthesis and HIV-1 protease (PR) inhibitory activity of 16 new peptidomimetic molecular tongs with a naphthalene scaffold. Their peptidic character was progressively decreased. Two of these molecules exhibited the best dimerization inhibition activity toward HIV-1 wild-type and multimutated ANAM-11 proteases obtained to date for this class of molecules (~40?nM for wild-type PR and 100?nM for ANAM-11 PR). Although the peptidic character of one molecular tong was completely suppressed, the mechanism of inhibition and inhibitory potency toward both proteases were maintained.  相似文献   
30.
Modelling the entire ductile fracture process remains a challenge. On the one hand, continuous damage models succeed in capturing the initial diffuse damage stage but are not able to represent discontinuities or cracks. On the other hand, discontinuous methods, as the cohesive zones, which model the crack propagation behaviour, are suited to represent the localised damaging process. However, they are unable to represent diffuse damage. Moreover, most of the cohesive models do not capture triaxiality effect. In this paper, the advantages of the two approaches are combined in a single damage to crack transition framework. In a small deformation setting, a nonlocal elastic damage model is associated with a cohesive model in a discontinuous Galerkin finite element framework. A cohesive band model is used to naturally introduce a triaxiality‐dependent behaviour inside the cohesive law. Practically, a numerical thickness is introduced to recover a 3D state, mandatory to incorporate the in‐plane stretch effects. This thickness is evaluated to ensure the energy consistency of the method and is not a new numerical parameter. The traction‐separation law is then built from the underlying damage model. The method is numerically shown to capture the stress triaxiality effect on the crack initiation and propagation.  相似文献   
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