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91.
Lothar Wondraczek Joachim Deubener Helena del Pozo Andreas Habeck 《Journal of the American Ceramic Society》2005,88(6):1673-1675
Classical theories of emulsion rheology yield information on the deformation of a liquid drop dispersed into another liquid matrix phase. By connecting the deformation and relaxation, respectively, and the capillary number of the dispersed phase, interfacial energy can be estimated. This was applied to demixing borosilicate and lead borate glasses, which are known to exhibit significant form anisotropy after elongation. Interfacial energies in these two systems were calculated based on graphical data of prior isothermal elongation experiments. The method is discussed in terms of experimental difficulties. It might provide an alternative way to overcome the obvious lack of information on interfacial energies in glasses. 相似文献
92.
Kiernan Michaela; Kraemer Helena C.; Winkleby Marilyn A.; King Abby C.; Taylor C. Barr 《Canadian Metallurgical Quarterly》2001,6(1):35
Identifying subgroups of high-risk individuals can lead to the development of tailored interventions for those subgroups. This study compared two multivariate statistical methods (logistic regression and signal detection) and evaluated their ability to identify subgroups at risk. The methods identified similar risk predictors and had similar predictive accuracy in exploratory and validation samples. However, the 2 methods did not classify individuals into the same subgroups. Within subgroups, logistic regression identified individuals that were homogeneous in outcome but heterogeneous in risk predictors. In contrast, signal detection identified individuals that were homogeneous in both outcome and risk predictors. Because of the ability to identify homogeneous subgroups, signal detection may be more useful than logistic regression for designing distinct tailored interventions for subgroups of high-risk individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Psychologists have expressed concern over the problems of empirically establishing the predictive validity of individual assessments, and in particular the lack of empirical evidence for this practice. A case study is used to illustrate the benefits and drawbacks of externally conducted individual assessments to illustrate why predictive validity is only part of the picture. The consulting psychologist and client relationship are compared with the doctor and patient relationship, and this analogy is used to analyze the role of the consulting psychologist, and of the individual assessments that they conduct. Finally, the implications of conducting individual assessments for practicing within a scientist-practitioner model are examined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Re-examines the life of Bertha Pappenheim, also known as J. Breuer and Freud's (1895) Anna O, in an attempt to understand her breakdown at age 21 and her emergence as a creative leader and reformer 8 yrs later. Understanding any life demands a theory that considers the individual's unique biological, familial, and sociocultural background, recognizes continuity over the lifespan, and contains a principle to account for such continuity. Classical drive theory does not meet these criteria. Based in part on J. Lichtenberg's (1989) concept of "self-righting," it is assumed that growth toward a healthy achieving self can occur at any age, given propitious conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
97.
Márcia Moraes Cascaes Giselle Maria Skelding Pinheiro Guilhon Eloisa Helena de Aguiar Andrade Maria das Gra?as Bichara Zoghbi Lourivaldo da Silva Santos 《International journal of molecular sciences》2015,16(10):23881-23904
Myrcia is one of the largest genera of the economically important family Myrtaceae. Some of the species are used in folk medicine, such as a group known as “pedra-hume-caá” or “pedra-ume-caá” or “insulina vegetal” (insulin plant) that it is used for the treatment of diabetes. The species are an important source of essential oils, and most of the chemical studies on Myrcia describe the chemical composition of the essential oils, in which mono- and sesquiterpenes are predominant. The non-volatile compounds isolated from Myrcia are usually flavonoids, tannins, acetophenone derivatives and triterpenes. Anti-inflammatory, antinociceptive, antioxidant, antimicrobial activities have been described to Myrcia essential oils, while hypoglycemic, anti-hemorrhagic and antioxidant activities were attributed to the extracts. Flavonoid glucosides and acetophenone derivatives showed aldose reductase and α-glucosidase inhibition, and could explain the traditional use of Myrcia species to treat diabetes. Antimicrobial and anti-inflammatory are some of the activities observed for other isolated compounds from Myrcia. 相似文献
98.
The objective was to assess food consumption among children attending non-profit nurseries in the Federal District, Brazil.A representative sample was obtained and stratified by income. Food intake among 678 children, between 4 and 82 months old, was analyzed in nine nurseries using the 24-h dietary recall and direct food weighing methods. In children under 13 months old mean intake was above AI between 93.6 to 100% for carbohydrates, proteins, vitamins B1, B2, B12, B6, and zinc. In children from 7-12 months 56.5% presented iron consumption below EAR. Calcium intake was above AI for 35.4% of children over 1 year old. For vitamins with EAR values, the prevalence of inadequate consumption was 53.2% for vitamin E, and 90% for folate for children over 12 months old. Iron and zinc intake was above UL for 6.4% and 32.5% of children under 1 year old, and 1.5% and 5.3% for the remaining children, respectively. Lipid percentage distribution range among children between 13 and 47 months old was within the acceptable range for only 16.2%. Nonetheless, children between 36 and 82 months of both genders presented mean intake below energy requirements. Inadequate consumption observed for some nutrients points to the need for improvements in the standard of meals and nutritional assistance offered to children enrolled in charitably run nurseries in the Federal District. 相似文献
99.
J. Marchi José Carlos Bressiani Ana Helena Almeida Bressiani Roy Edward Bruns 《International Journal of Applied Ceramic Technology》2010,7(4):493-501
Statistical mixture designs are used to systematically study the densification properties of silicon carbide (SiC) ceramics sintered with SiO2, Dy2O3, and Al2O3. Mixture models for percentage theoretical density and SiC weight loss as a function of the SiO2, Dy2O3, and Al2O3 oxide proportions have been determined and validated by analysis of variance. The results indicate a region confined by about 0–20 mol% silica, 50–65 mol% dysprosia, and 40–65 mol% alumina, with all samples containing 10% by volume of additives, and simultaneously maximization of density values and minimization of weight loss during SiC-based ceramic sintering. 相似文献
100.
Seixas TG Kehrig Hdo A Fillmann G Di Beneditto AP Souza CM Secchi ER Moreira I Malm O 《The Science of the total environment》2007,385(1-3):208-220
The present work tested whether ecological and biological variables have an influence on the assimilation of trace elements by the tissues of a cetacean from the Western South Atlantic Ocean. No significant differences were observed in the concentrations for both sexes. As individuals from the two sampling areas belong to distinct genetic and morphological populations, animals of similar body length were older on the southeastern than on the southern coast. The liver showed the highest concentrations of mercury, whereas the highest levels of cadmium were found in the kidney. Hepatic mercury, cadmium and selenium in individuals from the south coast were about four times as high as those from the southeast coast. However, arsenic in the liver and kidney were similar in both coastal areas. Hepatic mercury, cadmium and selenium concentrations increased with body length in individuals from the southeastern coast, although no significant correlations (P>0.05) were observed between body length from either area and the renal and hepatic As concentrations. A significant positive linear relationship was observed between molar concentrations of Hg and Se in the liver of all individuals from both areas (r2=0.93; P<0.001), presenting Se:Hg ratios close to 4. Differences found among the concentrations of Hg, Cd and Se in dolphins from both areas were probably due to the preferred prey, bioavailability of elements in each marine environment, and environment variables (water temperature, net primary production). As a consequence, concentrations of trace elements in the tissues of this species can be considered to be a result of the surrounding environment. 相似文献