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1.
Excessive energy intake may evoke complex biochemical processes characterized by inflammation, oxidative stress, and impairment of mitochondrial function that represent the main factors underlying noncommunicable diseases. Because cow milk is widely used for human nutrition and in food industry processing, the nutritional quality of milk is of special interest with respect to human health. In our study, we analyzed milk produced by dairy cows fed a diet characterized by a high forage:concentrate ratio (high forage milk, HFM). In view of the low n-6:n-3 ratio and high content of conjugated linoleic acid of HFM, we studied the effects of this milk on lipid metabolism, inflammation, mitochondrial function, and oxidative stress in a rat model. To this end, we supplemented for 4 wk the diet of male Wistar rats with HFM and with an isocaloric amount (82 kJ, 22 mL/d) of milk obtained from cows fed a diet with low forage:concentrate ratio, and analyzed the metabolic parameters of the animals. Our results indicate that HFM may positively affect lipid metabolism, leptin:adiponectin ratio, inflammation, mitochondrial function, and oxidative stress, providing the first evidence of the beneficial effects of HFM on rat metabolism.  相似文献   
2.
This article examines the relationships between the employment suburbanisation from central cities towards their suburbs, and the process of intra-urban specialisation that occurred simultaneously in the fifty largest French metropolitan areas. A methodology is proposed to identify urban subcentres and to analyse the effects of the intra-urban specialisations on suburbanisation patterns. We conclude that the specialisation of both subcentres and central cities has a significant effect on suburbanisation rates. Lastly, an intra-metropolitan shift/share analysis provides additional insights into the employment dynamics of central cities and suburbs during the last twenty years. Received: 25 July 2000 / Accepted: 29 May 2001  相似文献   
3.
Drawn symbolic pictures are an extension of drawn pictures obtained by associating a symbol from an alphabet to each point of the picture. In the paper we will address some new interesting issues derived from the introduction of the symbols and we will identify the conditions, which ensure the preservation of properties holding for drawn pictures in the setting of the proposed extension.  相似文献   
4.
Hydrogenated and chlorinated silicon films were used to deposit Schottky barrier solar cells. Photovoltaic characterization, together with the results of electronic transport measurements, led to the conclusion that the presence of chlorine is detrimental to the properties of this kind of device.  相似文献   
5.
The role of nitrogen dioxide in the selective reduction of NO by propane over a Cu-MFI zeolite is investigated. NO2 and NO reductions were carried out under similar conditions of reaction. In the presence of oxygen, the reduction of NO by C3H8 does not differ significantly from that of NO2. In the absence of oxygen, the reduction of NO2 by propane occurs with a partial decomposition of the nitric dioxide molecule. Such a decomposition leads to the formation of oxygen, which is responsible for the increase in catalytic activity by comparison with the same reaction performed with NO. NO2 formed and released in the gas phase during the reduction of NO by propane in the presence of oxygen does not play a predominant role in the catalytic process.  相似文献   
6.
Catalytic chlorination of methane was studied over SO 4 2– /ZrO2, Pt/SO 4 2– /ZrO2, and Fe/Mn/SO 4 2– /ZrO2 solid superacid catalysts. The reactions were carried out in a continuous flow reactor under atmospheric pressure, at temperatures below 240°C, with a gaseous hourly space velocity of 1000 ml/g h and a methane to chlorine ratio of 4 to 1. At 200°C with 30% chlorine converted the selectivity in methyl chloride exceeds 90%. At more elevated temperatures, the selectivity decreases but stays above 80% in methyl chloride at 225°C using the sulfated zirconia catalysts. The selectivity can be enhanced by adding platinum to sulfated zirconia catalysts. An iron and manganese-doped catalyst exhibited excellent selectivities at somewhat lower conversions. Methyl chloride is obtained at 235°C in selectivities greater than 85%. No chloroform or carbon tetrachloride is formed. The electrophilic insertion involves electron-deficient metal-coordinated chlorine into the methane C-H bond.Catalysis by solid superacids, 29. For part 28 see ref. [14].  相似文献   
7.
The photocatalytic oxidation of a common antibiotic, the lincomycin was carried out in aqueous suspensions of polycrystalline TiO2 Degussa P25 irradiated by sunlight. In order to improve the performance of the lincomycin degradation a hybrid system consisting of a solar photoreactor with the photocatalyst in suspension coupled with a membrane module, used to confine both photocatalyst and pollutants in the reaction environment, was tested.A preliminary study was carried out in order to determine some kinetics parameters of the drug photodegradation. The influence of initial substrate concentration on the lincomycin photooxidation rate was investigated. The photooxidation rate follows a pseudo-first order kinetics with respect to the lincomycin concentration under the used experimental conditions. The presence of the membrane reactor allows the catalyst separation and to operate in continuous mode as the membranes rejection for lincomycin and its oxidation products was quite high.  相似文献   
8.
In this article, a new extension of affine arithmetic is introduced. This technique is based on a quadratic form named general quadratic form. We focus here on the computation of reliable bounds of a function over a hypercube by using this new tool. Some properties of first quadratic functions and then polynomial ones are reported. In order to show the efficiency of such a method, ten polynomial global optimization problems are presented and solved by using an interval branch-and-bound based algorithm. The work of the first author was also supported by the Laboratoire de Mathématiques Appliquées CNRS–FRE 2570, Université de Pau et des Pays de l'Adour, France, and by the Laboratoire d'Electrotechnique et d'Electronique Industrielle CNRS–UMR5828, Group EM3, INPT–ENSEEIHT.  相似文献   
9.
We study feedback tracking problems for the planar vertical takeoff and landing (PVTOL) aircraft dynamics, which is a benchmark model in aerospace engineering. We provide a survey of the literature on the model. Then we construct new feedback stabilizers for the PVTOL tracking dynamics. The novelty of our work is in the boundedness of our feedback controllers and their applicability to cases where the velocity measurements may not be available, coupled with the uniform global asymptotic stability and uniform local exponential stability of the closed‐loop tracking dynamics and the input‐to‐state stable performance of the closed‐loop tracking dynamics with respect to actuator errors. Our proofs are based on a new bounded backstepping result. We illustrate our work in a tracking problem along a circle. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
10.
This paper addresses the annotation of the narrative features of media objects. Based on a relevant narratological and computational background, we introduce an ontology?Cbased model called Drammar, an annotation schema for the narrative features of media objects based on Drammar and a software tool, Cinematic, for annotating these objects and validating the annotation. Annotated media objects can also be automatically edited into sequences, with the twofold goal of testing the validity of the annotation??through the reconstruction of the baseline sequence??and exploring the possibility of alternative sequences. The software tool encodes both the narrative model and the annotation itself in ontological format, and relies on external ontologies for representing world knowledge and limit the arbitrariness of the annotation. The paper opens the way to the design of a general annotation schema for narrative multimedia with the long?Cterm goal of building large corpora of annotated video material and of bridging the gap between the low?Clevel signal analysis and the high?Clevel semantic representation of the narrative content of the media objects. Finally, the paper illustrates a few projects elaborated with the Drammar annotation and the Cinematic tool, with purposes of artistic research and cross?Cmedia analysis, that provide an empirical validation of the annotation process.  相似文献   
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