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71.
A synthetic route is presented to attain high‐optical‐quality multilayered structures that result from coupling ordered mesoporous titanium oxide thin films to the surface of a dense one‐dimensional photonic crystal. Such architectures present spectrally well‐defined photon resonant modes localized in the outer coating that finely respond to physicochemically induced modifications of its pore volume. The potential of these porous coatings in detection of environmental changes through variations of the photonic response of the ensemble is demonstrated by performing isothermal optical reflectance measurements under controlled vapor‐pressure conditions.  相似文献   
72.
Laurus nobilis is one of the most broadly used spices in Moroccan gastronomy. Its antimicrobial activity against both gram-positive and gram-negative bacterial species was demonstrated. Likewise, its toxicity was investigated on Swiss albinos' mice . Daily, mice were treated orally with 0.003 and 0.3 mg during 7 days. Plasmatic markers and enzymatic systems were assessed and histological alterations were evaluated. A significant increase in creatine phosphokinase level was observed. The microscopic evaluation showed that L. nobilis induces morphological perturbation in mice's liver. The results also showed an inhibitory effect of glyceraldehydes 3-phosphate dehydrogenase and an important increase in the level of thiobarbituric acid reactive substances and succinate dehydrogenase and no change in catalase activities. The results showed that L. nobilis induces toxicity at 0.3 mg/g mouse and affects energy metabolism and oxidative stress.

PRACTICAL APPLICATIONS


The aim of the present study is to determine the antimicrobial effect of Laurus nobilis on pathogens for potential application as herbal medicine in infusion or oral preparation. The effect of the spice extract was investigated on the metabolic markers, stress biomarkers and clinical parameters. This study was completed with histological coupes. To our knowledge, this is the first report to demonstrate the laurel effect on energy metabolism and oxidative stress.  相似文献   
73.
Utilities are an integral component of the total transportation network comprising highways, railways, airways, and waterways, as well as pipelines, wires, and cables that transport people, goods, and public services. The perennial dilemma of mutual interference between utility lines and transportation networks could be minimised making use of utility tunnel systems. Utilidors most striking feature is that they house several types of power, water, sewage, communications, gas and other statutory services in an easily accessible space. Placing utilities in tunnels under public rights-of-way reduces the continual cutting of pavements resulting from utility burial practices and facilitates the installation, inspection, replacement, and maintenance operations. Utility tunnels and transportation networks may not be compatible at transmission levels. Highway systems are generally planned to avoid high-density areas insofar as is possible. However, where the location of utility networks coincides sufficiently with the highway routes, the situation becomes more favourable to the utility tunnel concept. This paper discusses how compatibility of utility system networks with highway system networks could be greatly improved by appropriate attention to utilidor systems in urban planning. A sustainable approach to the dilemma of where to locate utilities in urban streets and highways has become urgent as the need for services expands in our modern cities. Interference between the safety and flow of highway traffic and utility tunnel operation could be a problem unless adequate measures are undertaken.  相似文献   
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The electron-transfer behavior of electroactive hydrogels formed by cross-linking ferrocene poly(allylamine) (Fc-PAA) and glucose oxidase is investigated as a function of electrolyte ionic strength using several techniques. Cyclic voltammetry and electrochemical impedance spectroscopy show that the quantity cD(e)(1/2) increases with electrolyte concentration. Enhancement of enzyme catalysis for the oxidation of glucose mediated by Fc-PAA is also apparent at higher KNO(3) concentration. The electroactive redox center concentration, c, and the diffusion coefficient due to electron hopping in the gel, D(e), are independently measured by chronoamperometry at ultramicroelectrodes. Larger electrolyte ionic strength induces an increase in electroactive redox center concentration while D(e) slightly decreases. These results are rationalized in terms of the electrostatic interactions within the redox gel backbone due to water and ion exchange with the external electrolyte, producing swelling and shrinking of the hydrogel.  相似文献   
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Refusal to eat by the elderly, and subsequent malnutrition, occurs in both institutional and community settings. Causes include physiologic changes associated with aging, mental disorders such as dementia and depression, and medical, social, and environmental factors. Treatment approaches call for management of these causes while considering the roles that medicine, ethics, and culture play in the process.  相似文献   
79.
The present work addresses a schedule designed to render rats alcoholic by offering them free access to a 20% (v/v) ethanol solution over 6 weeks. A solid diet and water (for controls) were fully available ad lib. in the animals' cages. The treatment was observed to achieve some effects suitable for the chronic alcoholization of rats: (1) Ethanol furnished the 36% of the calories of the diet of ethanol-treated rats; (2) The daily ethanol intake achieved was 12.05 +/- 1.18 g ethanol/kg weight; (3) The morning blood ethanol level was 0.45 g/litre; (4) Ethanol-treated rats deprived of ethanol showed several withdrawal symptoms. These results agree with those obtained by standard liquid diets, suggesting that the current protocol can be used to achieve a status of chronic alcoholization in rats.  相似文献   
80.
Two patients with sinus tracts from retained T-fasteners following PEG tube placement are reported. Both patients had the PEG tubes subsequently removed and presented with purulent discharge and granulations near well-healed gastrostomy sites. The management of this complication and a possible method of prevention are discussed.  相似文献   
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