990 resultados para compatible osmolyte
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Why females of many species mate multiply in the absence of direct benefits remains an open question in evolutionary ecology. Interacting and mating with multiple males can be costly to females in terms of time, resources, predation risk, and disease transmission. A number of indirect genetic benefits have been proposed to explain such behaviors, but the relative importance of these mechanisms in natural systems remains unclear. We tested for several direct and indirect benefits of polyandry in the walking stick Timema cristinae. We found no evidence of direct benefits with respect to longevity or fecundity. However, male x female genotypic interactions affected egg-hatching success and offspring production independent of relatedness, suggesting that mating with certain males benefits females and that the best male may differ for each female. Furthermore, multiply mated females biased paternity toward one or few males, and the extent of this bias was positively correlated to egg-hatching success. Our data, therefore, provide evidence for indirect benefits through compatibility effects in this species. By mating multiply, females may improve their chances of mating with a compatible male if compatibility cannot be assessed before mating. Such compatibility effects can explain the evolution and maintenance of polyandry in Timema and many other species.
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Abstract Objective: To estimate the prevalence and evaluate sonographic findings compatible with changes consistent with hepatic steatosis in patients referred for abdominal ultrasonography at four reference centers in Aracaju, SE, Brazil. Materials and Methods: Prospective, descriptive survey, with analytical and quantitative approach, comprising abdominal ultrasonography scans performed with a convex, dynamic 3.75 MHz transducer. Liver dimensions and parenchymal echotexture were evaluated, classifying hepatic steatosis into grades (1, 2 or 3). The SPSS® 22.0 software was used for statistical analysis, adopting p < 0.05 as significance level. Results: A total of 800 individuals (561 women and 239 men) were evaluated. The prevalence of steatosis was 29.1%, and the male patients were most affected, presenting with more advanced grades of disease (p = 0.021), as follows: 119 grade 1 (51.0%); 94 grade 2 (40.4%); and 20 grade 3 (8.6%). The median age patients' was 46 years. Conclusion: In the present study sample, the prevalence of hepatic steatosis was high, particularly in the male patients. Ultrasonography is suggested as a first choice for the diagnosis of this condition, considering its wide availability, low cost and absence of side effects or risks to the patient.
(Minimally) 'epsilon'-incentive compatible competitive equilibria in economies with indivisibilities
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We consider competitive and budget-balanced allocation rules for problems where a number of indivisible objects and a fixed amount of money is allocated among a group of agents. In 'small' economies, we identify under classical preferences each agent's maximal gain from manipulation. Using this result we find the competitive and budget-balanced allocation rules which are minimally manipulable for each preference profile in terms of any agent's maximal gain. If preferences are quasi-linear, then we can find a competitive and budget-balanced allocation rule such that for any problem, the maximal utility gain from manipulation is equalized among all agents.
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Cette thèse contribue à l'état actuel des connaissances sur la compatibilité des nouveaux bâtiments avec les environnements urbains historiques. Elle suit un mode de présentation classique: Introduction, Revue de Littérature, Méthodologie, Résultats, Discussion et Conclusion. Le problème étudié est le manque d'orientation pour intégrer les processus de développement et de sauvegarde dans les contextes établis. La littérature récente révèle que les règles de préservation, aussi appelées normes et lignes directrices, ne peuvent pas garantir une relation compatible entre une intervention et son milieu. La pensée contemporaine dans le domaine de la conservation et de la gestion du patrimoine invite donc l’exploration d'autres moyens pour lier la nouvelle architecture à l'ancienne. Ainsi, le présent projet de recherche explore une approche alternative aux règles de préservation en vue d’atteindre le but de nouveaux bâtiments compatibles et d’améliorer la prise de décision fondée sur les valeurs. Pour produire des résultats spécifiques et convaincants, un cas a été sélectionné. Celui-ci est une ville dans la région du Golfe Arabe : la Ville de Koweït. Le résultat principal est le développement d’une approche, mise en œuvre en posant des questions approfondies sur le lieu, la conception et la construction des nouveaux bâtiments. Les questions suggérées dans la thèse mettent l’accent sur les valeurs patrimoniales et les choix de conception afin de permettre un changement réfléchi au sein des environnements urbains historiques. Elles aident aussi à évaluer les nouvelles propositions de projets au cas par cas. Pour démontrer comment cette approche pourrait être présentée et utilisée par les requérants et les évaluateurs, un modèle théorique est proposé. Ce modèle a ensuite été discuté avec des professionnels locaux et internationaux qui ont identifié ses forces et ses limites. En conclusion, l’ensemble des résultats montre que la mise à disposition de règles et / ou de questions approfondies n’est pas une solution satisfaisante puisqu’il y a d'autres enjeux importants qui devraient être abordés: comment appliquer l'orientation efficacement une fois qu’elle a été créée, comment développer la compétence liée à la prise de décision fondée sur les valeurs et comment insérer la conservation du patrimoine dans la mentalité du gouvernement local et des communautés. Lorsque ces enjeux seront traités, le patrimoine pourra devenir partie intégrante du processus de planification, ce qui est le but ultime. Enfin, cinq axes de recherche sont recommandés pour poursuivre l’exploration des idées introduites dans cette étude.
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Bio-compatible magnetic fluids having high saturation magnetization find immense applications in various biomedical fields. Aqueous ferrofluids of superparamagnetic iron oxide nanoparticles with narrow size distribution, high shelf life and good stability is realized by controlled chemical co-precipitation process. The crystal structure is verified by X-ray diffraction technique. Particle sizes are evaluated by employing Transmission electron microscopy. Room temperature and low-temperature magnetic measurements were carried out with Superconducting Quantum Interference Device. The fluid exhibits good magnetic response even at very high dilution (6.28 mg/cc). This is an advantage for biomedical applications, since only a small amount of iron is to be metabolised by body organs. Magnetic field induced transmission measurements carried out at photon energy of diode laser (670 nm) exhibited excellent linear dichroism. Based on the structural and magnetic measurements, the power loss for the magnetic nanoparticles under study is evaluated over a range of radiofrequencies.
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In the last decades considerable headway has been made in research and development of phyto-chemical pesticides. The most notable recent success is the commercial development of neem products for insect control. The present investigation on Environmentally Compatible Phyto-Chemical Larvicides for Mosquito Control was undertaken to identify plants of the locality with potential larvicidal activity on mosquito larvae. This has been achieved by screening 17 plant species against four mosquito species. The observation and data are compiled in six chapters .
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Fluorescence is a powerful tool in biological research, the relevance of which relies greatly on the availability of sensitive and selective fluorescent probes. Nanometer sized fluorescent semiconductor materials have attracted considerable attention in recent years due to the high luminescence intensity, low photobleaching, large Stokes’ shift and high photochemical stability. The optical and spectroscopic features of nanoparticles make them very convincing alternatives to traditional fluorophores in a range of applications. Efficient surface capping agents make these nanocrystals bio-compatible. They can provide a novel platform on which many biomolecules such as DNA, RNA and proteins can be covalently linked. In the second phase of the present work, bio-compatible, fluorescent, manganese doped ZnS (ZnS:Mn) nanocrystals suitable for bioimaging applications have been developed and their cytocompatibility has been assessed. Functionalization of ZnS:Mn nanocrystals by safe materials results in considerable reduction of toxicity and allows conjugation with specific biomolecules. The highly fluorescent, bio-compatible and water- dispersible ZnS:Mn nanocrystals are found to be ideal fluorescent probes for biological labeling
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Bacillus smithii BTMS 11, isolated from marine sediment, produced alkaline and thermostable lipase. The enzyme was purified to homogeneity by ammonium sulfate precipitation and ion exchange chromatography which resulted in 0.51 % final yield and a 4.33 fold of purification. The purified enzyme was found to have a specific activity of 360 IU/mg protein. SDS-PAGE analyses, under non-reducing and reducing conditions, yielded a single band of 45 kDa indicating the single polypeptide nature of the enzyme and zymogram analysis using methylumbelliferyl butyrate as substrate confirmed the lipolytic activity of the protein band. The enzyme was found to have 50 C and pH 8.0 as optimum conditions for maximal activity. However, the enzyme was active over wide range of temperatures (30–80 C) and pH (7.0–10.0). Effect of a number of metal salts, solvents, surfactants, and other typical enzyme inhibitors on lipase activity was studied to determine the novel characteristics of the enzyme. More than 90 % of the enzyme activity was observed even after 3 h of incubation in the presence of commercial detergents Surf, Sunlight, Ariel, Henko, Tide and Ujala indicating the detergent compatibility of B. smithii lipase. The enzyme was also found to be efficient in stain removal from cotton cloths. Further it was observed that the enzyme could catalyse ester synthesis between fatty acids of varying carbon chain lengths and methanol with high preference for medium to long chain fatty acids showing 70 % of esterification. Results of the study indicated scope for application of this marine bacterial lipase in various industries
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Understanding how the human visual system recognizes objects is one of the key challenges in neuroscience. Inspired by a large body of physiological evidence (Felleman and Van Essen, 1991; Hubel and Wiesel, 1962; Livingstone and Hubel, 1988; Tso et al., 2001; Zeki, 1993), a general class of recognition models has emerged which is based on a hierarchical organization of visual processing, with succeeding stages being sensitive to image features of increasing complexity (Hummel and Biederman, 1992; Riesenhuber and Poggio, 1999; Selfridge, 1959). However, these models appear to be incompatible with some well-known psychophysical results. Prominent among these are experiments investigating recognition impairments caused by vertical inversion of images, especially those of faces. It has been reported that faces that differ "featurally" are much easier to distinguish when inverted than those that differ "configurally" (Freire et al., 2000; Le Grand et al., 2001; Mondloch et al., 2002) ??finding that is difficult to reconcile with the aforementioned models. Here we show that after controlling for subjects' expectations, there is no difference between "featurally" and "configurally" transformed faces in terms of inversion effect. This result reinforces the plausibility of simple hierarchical models of object representation and recognition in cortex.
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La protección internacional de los derechos humanos se ha fundamentado en el principio de universalidad que caracteriza esta preocupación del derecho internacional, pero la intervención de criterios de selectividad ha generado una discordancia en los resultados. Diferentes factores han limitado la protección efectiva: no existe claridad frente a conceptos como obligatoriedad y exigibilidad de los instrumentos, normas de ius cogens y jerarquía normativa; influencia de la coyuntura política y las relaciones internacionales entre Estados. Los Estados delegan en las diferentes organizaciones internacionales el cumplimiento de sus obligaciones; los Estados son selectivos en sí, por políticas contingentes; las instituciones regionales incentivan la selectividad al incluir en sus decisiones temas no jurídicos. Para enfrentar esto, el derecho internacional debe restablecer los valores originales, volviendo a los orígenes de la protección internacional y a la finalidad de proporcionar acceso directo a los individuos ante las instituciones internacionales, de modo que se garantice tanto el Estado de derecho como la imparcialidad profesional, así como los cambios institucionales que podrían justificarse para transformar la protección buscada en una realidad universal.
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Resumen basado en el del autor. Resumen en castellano e inglés. Este artículo se incluye en el monográfico 'Educación y Deporte'
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Cash-constrained wildlife departments must increasingly look towards revenue-generating activities such as sales of permits for hunting common species combined with fines for those caught with rare species. Pertinent to west Africa, an optimal enforcement model demonstrates the conditions under which a department with neither external budget nor tourism revenue can fully protect a rare species, and the impact on other species and local hunters' livelihoods. The department's effectiveness is shown to depend critically on the extent to which hunters can discriminate among different species. Improvements in hunting technology selectivity are therefore a substitute for increased enforcement spending.