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71.
Netto I Bostan V McCarthy L Laursen A Gilbride K Mehrvar M Pushchak R 《Water science and technology》2012,66(8):1708-1715
The short-term impacts of atrazine (herbicide), tributyltin (organometal) and copper on the behaviour of Euglena gracilis Klebs (Euglenophyta) were assessed. First, the ECOTOX automated image analysis system was used, which measured swimming velocity, cell shape, percentage of cells swimming upwards, and randomness of swimming. Next, visual observation by microscopy was used to measure percentage of cell motility and cell shape. Behavioural changes can be used as an indicator of stress in less than 24 h, potentially making them suitable for inclusion in early-warning systems for water quality. Findings indicate that E. gracilis is a very sensitive organism to copper, showing inhibition of motility with visual observation at 0.8 μmol/L within 1 h. The image analysis system was in general less sensitive than visual observation for detecting behavioural changes after incubation in copper. In contrast, after exposure to organic contaminants atrazine and tributyltin, the ECOTOX system detected small changes in the number of cells swimming upwards (antigravitactic behaviour) at higher concentrations. 相似文献
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The concept of cardiac reconditioning centers for the prevention and rehabilitation of coronary patients has been tremendously successful in Germany over the past 20 years. At least 40 such centers are located throughout the country. Physicians, nurses, and physical therapists work closely together in the various facets of the rehabilitation process. The financial backing for these facilities is primarily through governmental and regional insurance companies, whose officials are apparently convinced that in the long run supporting preventive measures is financially sound. Objective data supporting their convictions come from studies such as that of Brusis, who showed that such as that of 1,500 employees was diminished by nearly 70 percent during a two-year period after cardiac reconditioning, as compared to a similar time period before the rehabilitation experience. Subjective benefits, which are extremely difficult to quantitate in meaningful terms, were nonetheless expressed by nearly all the patients with whom I conversed. Perhaps they have experienced the same feelings that Mark Twain did when he observed that "all frets and worries and chafings sank to sleep in the presence of the benignant serenity of the Alps; the Great Spirit of the Mountains breathed his own peace upon their hurt minds and sore hearts and healed them." 相似文献
74.
M. S. Netto A. M. Annaswamy R. Ortega P. Moya 《International journal of control》2013,86(14):1312-1321
In this paper we deal with the problem of adaptive control of a class of non-linearly parametrized plants. The main contribution is to show that, through a well-chosen reparametrization, it is possible to transform the non-convex nonlinear parametrization into a convex one, a property that is used to design a globally stable adaptive controller. 相似文献
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Patricia B. da Silva Paula C. de Souza Giovana Maria Fioramonti Calixto Erica de O. Lopes Regina C. G. Frem Adelino V. G. Netto Antonio E. Mauro Fernando R. Pavan Marlus Chorilli 《International journal of molecular sciences》2016,17(5)
Tuberculosis (TB) is an infectious disease caused mainly by the bacillus Mycobacterium tuberculosis (Mtb), presenting 9.5 million new cases and 1.5 million deaths in 2014. The aim of this study was to evaluate a nanostructured lipid system (NLS) composed of 10% phase oil (cholesterol), 10% surfactant (soy phosphatidylcholine, sodium oleate), and Eumulgin® HRE 40 ([castor oil polyoxyl-40-hydrogenated] in a proportion of 3:6:8), and an 80% aqueous phase (phosphate buffer pH = 7.4) as a tactic to enhance the in vitro anti-Mtb activity of the copper(II) complexes [CuCl2(INH)2]·H2O (1), [Cu(NCS)2(INH)2]·5H2O (2) and [Cu(NCO)2(INH)2]·4H2O (3). The Cu(II) complex-loaded NLS displayed sizes ranging from 169.5 ± 0.7095 to 211.1 ± 0.8963 nm, polydispersity index (PDI) varying from 0.135 ± 0.0130 to 0.236 ± 0.00100, and zeta potential ranging from −0.00690 ± 0.0896 to −8.43 ± 1.63 mV. Rheological analysis showed that the formulations behave as non-Newtonian fluids of the pseudoplastic and viscoelastic type. Antimycobacterial activities of the free complexes and NLS-loaded complexes against Mtb H37Rv ATCC 27294 were evaluated by the REMA methodology, and the selectivity index (SI) was calculated using the cytotoxicity index (IC50) against Vero (ATCC® CCL-81), J774A.1 (ATCC® TIB-67), and MRC-5 (ATCC® CCL-171) cell lines. The data suggest that the incorporation of the complexes into NLS improved the inhibitory action against Mtb by 52-, 27-, and 4.7-fold and the SI values by 173-, 43-, and 7-fold for the compounds 1, 2 and 3, respectively. The incorporation of the complexes 1, 2 and 3 into the NLS also resulted in a significant decrease of toxicity towards an alternative model (Artemia salina L.). These findings suggest that the NLS may be considered as a platform for incorporation of metallic complexes aimed at the treatment of TB. 相似文献
77.
Abstract Protein hydrolysates play an important function in many special dietary foods, e.g. for infants, those with genetic disorders, athletes and geriatrics. Because of hydrolysis these materials are more hygroscopic than the initial intact protein. In this reset the moisture sorption isotherms and the glass transition profile as a function of moisture content for fish protein hydrolysates (FPH), whey protein hydrolysates (WPH) and casein hydrolysates (CH) were determined. The properties of each hydrolysates were related to molecular weight with a lower glass transition curve at lower molecular weight, the Tg was proportional to degree of hydrolysis. These hydrolysates may be as important as sugars in lowering Tg. Fish moisture sorption was related to hydrolysis. CH was less susceptible to caking than FPH and WPH. 相似文献
78.
JAROSLAV KAŠPAR IGOR KOROPECKÝ EDUARD BRYNDA STANISLAV NEŠPUdotREK 《International Journal of Electronics》2013,100(5):1041-1042
Langmuir-Blodgett films have been prepared from copper tetra-4-t-butylphthalocyanine. A voltage dependence of capacitance can be attributed to the presence of a Schottky depletion layer. The barrier potential was determined as l·4eV, and the carrier concentration about 1024m?3 相似文献
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80.
W. F. P. Neves‐Junior C. F. de O. Graeff M. Ferreira M. Mulato M. S. Bernardes J. Coutinho‐Netto 《应用聚合物科学杂志》2006,100(1):702-707
The mechanical properties of rubber tubes produced by dip‐coating technique and the influence of the fabrication process on their structural properties were evaluated. Cyclic tension versus deformation tests were performed to investigate the elastic properties of the samples and to understand the changes in rubber tubes behavior under repetitive stress. The effect of the wall thickness on the elastic response of the tubes was also studied. The mechanical properties of opened tubes were also investigated for transversal and longitudinal directions to evaluate the influence of the fabrication process on the alignment of the polymer chains. This investigation indicated that the fabricated tubes are resistant and extremely elastic. They can be elongated up to 800% of its initial length before rupture, and thicker tubes are a bit more resistant to elongation than the thinner ones. In addition, the fabricated tubes have an anisotropic structure due to the fabrication process. Finally, natural rubber tubes may have a great potential to be used as vascular prosthesis, or in other applications that require a large range of resistance and elasticity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 702–707, 2006 相似文献