Microstructure formation in chalcogenide thin films assisted by thermal dewetting

The spontaneous formation of self-assembled and/or self-organized patterns is a fundamental and technologically significant topic. This process is achieved via a phenomenon called dewetting, should it be thermally induced, or caused by laser exposure. Although dewetting seems to be a well-known phenomenon for metallic and polymeric thin films, no proper investigation regarding glassy thin films seems to have been done. Thus, in the present study we try to elaborate on the process of thermal dewetting applied to glassy thin films of the system Ag_x(As₂₀S₈₀)_100?x.     

Polyoxometalate catalyzed ozonation of chemical pulps in organic solvent media

Polyoxometalate (POM) catalyzed ozonation of chemical pulps in organic solvent media was found to be particularly effective and selective environmentally benign bleaching approach providing a way for substantial increase in pulp brightness, viscosity and degree of delignification in comparison with other ozone-based bleaching techniques. A series of tested low-boiling polar aprotic and protic organic solvents showed a well-defined capacity for ozonation improvement in the presence of Keggin-type heteropolyanion [PMo₇V₅O₄₀]⁸⁻ (HPA-5). Even moderate solvent proportion of 6% (w/w) in the reaction solution caused additional gain in brightness up to 3.4% ISO with simultaneous increase in pulp viscosity up to 8.8% and lignin removal up to 18.9% after HPA-5 catalyzed ozonation (0.8% O₃; 0.5 mM HPA), as compared with the control solvent-free process. An aqueous acetone solution was found to be the preferred reaction medium in terms of pulp brightening and delignification. Under optimized conditions, the POM-catalyzed ozonation of eucalypt kraft pulp in acetone/water solution showed remarkable brightness improvement by 15.1% ISO with additional lignin removal by 39.4% and increase in intrinsic viscosity by 3% in comparison with pulp bleached in water media.     

Relation among taste-related compounds (phenolics and caffeine) and sensory profile of erva-mate (Ilex paraguariensis)

Erva-mate (Ilex paraguariensis St. Hil.) is a native species from temperate regions of South America, such as Brazil, Paraguay, and Argentina, that is consumed as a beverage known as mate. The objective of this research was to determine the content of caffeic acid, catechin, chlorogenic acid, caffeine, and gallic acid in mate to explain their influence in beverage taste and sensory differences between native and reforested plants, as well as between beverages from plants of different regions of Brazil (Santa Catarina and Rio Grande do Sul states). Compounds were determined by HPLC and results were related to a sensory evaluation performed by trained tasters. Tasters considered the beverage from reforested plants to be more bitter than the beverage from native plants. Beverages from reforested plants had significantly higher caffeic acid and lower catechin, chlorogenic acid, caffeine, and gallic acid content than native plants. Beverages from plants of Santa Catarina state had significantly higher catechin, caffeine, and gallic acid content than plants from Rio Grande do Sul state.     

Interfacial Energy in Phase-Separated Glasses from Emulsion Rheology

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.     

Do logistic regression and signal detection identify different subgroups at risk? Implications for the design of tailored interventions.

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)     

Preoccupied with predictive validity: An alternative perspective.

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)     

The mysterious metamorphoses of Bertha Pappenheim: Anna O. revisited.

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)     

Constituents and Pharmacological Activities of Myrcia (Myrtaceae): A Review of an Aromatic and Medicinal Group of Plants

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.