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141.
Hurtado Sylvia; Griffin Kimberly A.; Arellano Lucy; Cuellar Marcela 《Canadian Metallurgical Quarterly》2008,1(4):204
The authors synthesize existing climate research and climate instruments, as well as introduce several frameworks to help educators understand how institutions and researchers have assessed diversity in the college environment. Over 90 instruments were reviewed and examined for their attention to multiple dimensions of the campus climate, diversity initiatives, and outcomes measures that capture students' values, skills, and knowledge for participation in a diverse society. Frameworks presented include a broad definition of the campus climate, a typology of campus initiatives based on an inventory of campus practice, and a typology of representative outcomes that capture cognitive, socio-cognitive, values/attitudes, and preparation for a multicultural society. Campuses that strive to become functional multicultural learning environments can now rely on a body of empirical information to guide practice and critical self-assessment to deepen their commitment to diversity. The authors recommend that campuses integrate their assessment of the climate with the evaluation of student outcomes and campus practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
142.
Rafael Caetano Lisba Castro de Andrade Nathlia Kelly de Araújo Manoela Torres-Rêgo Allanny Alves Furtado Alessandra Daniele-Silva Weslley de Souza Paiva Julia Maria de Medeiros Dantas Nayara Sousa da Silva Arnbio Antnio da Silva-Júnior Marcela Abbott Galvo Ururahy Cristiane Fernandes de Assis Leandro De Santis Ferreira Hugo Alexandre Oliveira Rocha Matheus de Freitas Fernandes-Pedrosa 《International journal of molecular sciences》2021,22(19)
The search for promising biomolecules such as chitooligosaccharides (COS) has increased due to the need for healing products that act efficiently, avoiding complications resulting from exacerbated inflammation. Therefore, this study aimed to produce COS in two stages of hydrolysis using chitosanases derived from Bacillus toyonensis. Additionally, this study aimed to structurally characterize the COS via mass spectrometry, to analyze their biocompatibility in acute toxicity models in vivo, to evaluate their healing action in a cell migration model in vitro, to analyze the anti-inflammatory activity in in vivo models of xylol-induced ear edema and zymosan-induced air pouch, and to assess the wound repair action in vivo. The structural characterization process pointed out the presence of hexamers. The in vitro and in vivo biocompatibility of COS was reaffirmed. The COS stimulated the fibroblast migration. In the in vivo inflammatory assays, COS showed an antiedematogenic response and significant reductions in leukocyte migration, cytokine release, and protein exudate. The COS healing effect in vivo was confirmed by the significant wound reduction after seven days of the experiment. These results indicated that the presence of hexamers influences the COS biological properties, which have potential uses in the pharmaceutical field due to their healing and anti-inflammatory action. 相似文献
143.
Vivian Boesso Oriani Gustavo Molina Marcela Chiumarelli Gláucia Maria Pastore Miriam Dupas Hubinger 《Journal of food science》2014,79(2):E189-E194
Edible coatings were produced using cassava starch (2% and 3% w/v) containing cinnamon bark (0.05% to 0.30% v/v) or fennel (0.05% to 0.30% v/v) essential oils. Edible cassava starch coating at 2% and 3% (w/v) containing or not containing 0.30% (v/v) of each essential oils conferred increased in water vapor resistance and decreased in the respiration rates of coated apple slices when compared with uncoated fruit. Cassava starch coatings (2% w/v) added 0.10% or 0.30% (v/v) fennel or cinnamon bark essential oils showed antioxidant capacity, and the addition of 0.30% (v/v) of each essential oil demonstrated antimicrobial properties. The coating containing cinnamon bark essential oil showed a significant antioxidant capacity, comparing to fennel essential oil. Antimicrobial tests showed that the addition of 0.30% (v/v) cinnamon bark essential oil to the edible coating inhibited the growth of Staphylococcus aureus and Salmonella choleraesuis, and 0.30% fennel essential oil inhibited just S. aureus. Treatment with 2% (w/v) of cassava starch containing 0.30% (v/v) of the cinnamon bark essential oil showed barrier properties, an antioxidant capacity and microbial inhibition. 相似文献
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Maitane Gonzlez-Arceo Ivn Gomez-Lopez Helen Carr-Ugarte Itziar Eseberri Marcela Gonzlez M. Pilar Cano María P. Portillo Saioa Gmez-Zorita 《International journal of molecular sciences》2023,24(1)
Isorhamnetin is a plant-derived secondary metabolite which belongs to the family of flavonoids. This review summarises the main outcomes described in the literature to date, regarding the effects of isorhamnetin on obesity from in vitro and in vivo studies. The studies carried out in pre-adipocytes show that isorhamnetin is able to reduce adipogenesis at 10 μM or higher doses and that these effects are mediated by Pparγ and by Wnt signalling pathway. Very few studies addressed in rodents are available so far. It seems that treatment periods longer than two weeks are needed by isorhamnetin and its glycosides to be effective as anti-obesity agents. Nevertheless, improvements in glycaemic control can be observed even in short treatments. Regarding the underlying mechanisms of action, although some contradictory results have been found, reductions in de novo lipogenesis and fatty acid uptake could be proposed. Further research is needed to increase the scientific evidence referring to this topic; studies in animal models are essential, as well as randomised clinical trials to determine whether the positive results observed in animals could also be found in humans, in order to determine if isorhamnetin and its glycosides can represent a real tool against obesity. 相似文献
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Analysis and experimentation of nonlinear adaptive controllers forthe series resonant converter 总被引:1,自引:0,他引:1
Carrasco J.M. Galvan E. Valderrama G.E. Ortega R. Stankovic A.M. 《Power Electronics, IEEE Transactions on》2000,15(3):536-544
It is the purpose of this paper to explore the problem of regulating the output voltage of a DC-to-DC series resonant power converter (SRC). These converters have highly nonlinear dynamics fed by a bipolar square signal generator whose commuting frequency is the only accessible control variable in the control architecture that the authors study. Therefore, they are confronted with the problem of controlling a nonlinear switched system by means of a modulating frequency signal. Two more complications that make this problem more challenging are that the full state is typically not available for measurement, and that the output load, usually represented by a resistance, is unknown. They show here that-for constant control input-SRCs have a unique globally attractive periodic orbit, which motivates them to consider a first harmonic approximation of the system. They then prove that this reduced model consists of a known static nonlinearity in cascade with a first order system with unknown parameters, for which adaptive output feedback solutions can be derived. They propose two different schemes, first a passivity-based controller which, as usual in these schemes, achieves asymptotically the inversion of the nonlinearity. They prove that, under some practically reasonable considerations, this control law reduces to the dissipative controller recently proposed by Stankovic et al. The second scheme directly inverts the static nonlinearity and applies standard adaptive techniques to the resulting linear system. The three controllers are implemented in an experimental setup and the results are presented as a comparative study 相似文献
148.
María F. Andreoli Marcela I. Martinelli María V. Scalerandi Ana C. Fariña María R. Williner Claudio A. Bernal 《European Journal of Lipid Science and Technology》2012,114(7):718-725
CLA has been reported to have beneficial and controversial effects on glucose and lipid metabolism. Besides, high fat (HF) diets induce alterations in liver and muscle lipid deposition, which could be associated with anomalous glucose utilization. Therefore, our aim was to evaluate whether the intake of CLA could prevent alterations in glycolytic intermediate metabolites and glycogen deposition induced by a HF diet. For this purpose, growing mice were fed a control diet (7% corn oil), a HF diet (20% corn oil), or a HF diet containing 17% corn oil + 3% CLA for 30 days. Liver and muscle glucose intermediate metabolites and glycogen were assessed. Liver glycolysis was inhibited by HF, reflected by a decreased flow of substrates through phosphofructokinase‐1α linked to elevated citrate. CLA at HF diet prevented these alterations while increasing the lactate and glycogen synthesis. In the muscle, the HF diet emphasized the reduction of the flux through phosphofructokinase‐1α, without additional changes in total glycogen levels. In conclusion, dietary CLA partially prevented glycolytic pathway alterations in the liver but not in the muscle of mice fed a HF diet, associated with adverse effects as sustained hyperglycemia and hepatic lactate accumulation. Practical applications: The present study evaluates the potential use of CLA and its consequences on several aspects of glucose metabolism. Considering that the FDA has recently approved CLA as a Generally Recognized as Safe (GRAS) category, a measure that will foster the commercial production of food and beverages with CLA supplementation, we believe it is relevant to study its potential functional properties on glucose metabolism in an experimental animal model characterized by alterations in liver and muscle lipid deposition. 相似文献
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