Construction of the energy diagram of an organic semiconductor film on SnO2:F by surface photovoltage spectroscopy

The work functions of solid layers of the hole conductors diketopyrrolopyrrole (DPP) and dithioketopyrrolopyrrole (DTPP) on SnO₂:F were measured by the Kelvin probe technique. From the dependence of the work function on the layer thickness, the width of the space charge layer at the interface and the total voltage drop over the organic layer were deduced. The presence of two photoactive areas, one at the air/D(T)PP interface and one at the D(T)PP/SnO₂:F interface, was demonstrated by measuring the surface photovoltage (SPV) spectra under front and back side illumination, and their dependence on the layer thickness. Calculation of the contributions of each of these areas to the SPV permitted the construction of the energy diagram of the DTPP/SnO₂:F junction. The spectral dependence of the SPV for D(T)PP layers is weak. For thick layers of D(T)PP, the SPV spectrum under front side illumination follows the absorption spectrum, while the one under back side illumination is different in shape. For thinner layers the SPV spectrum is a superposition of the front side signal and back side signal, modulated by an internal filter effect of the organic layer itself.     

A causal model of the educational plans and career expectations of Mexican American high school girls.

A structural model predicting the educational and career expectations of 282 Mexican American high school girls was developed and then tested on samples of 247 Mexican American boys and 228 European American girls. Predictors included socioeconomic status, acculturation, academic achievement, instrumentality, expressiveness, gender role attitudes, parental and teacher support, family and career commitment, and perceptions of barriers. Results indicated that the initial model was plausible in the sample of Mexican American girls. Findings from the multiple-groups analyses provided evidence supporting the primacy of cultural influences over gender in predicting the educational and career expectations of Mexican American girls. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Searching for the structure of coping: A review and critique of category systems for classifying ways of coping.

From analyzing 100 assessments of coping, the authors critiqued strategies and identified best practices for constructing category systems. From current systems, a list of 400 ways of coping was compiled. For constructing lower order categories, the authors concluded that confirmatory factor analysis should replace the 2 most common strategies (exploratory factor analysis and rational sorting). For higher order categories, they recommend that the 3 most common distinctions (problem- vs. emotion-focused, approach vs. avoidance, and cognitive vs. behavioral) no longer be used. Instead, the authors recommend hierarchical systems of action types (e.g., proximity seeking, accommodation). From analysis of 6 such systems, 13 potential core families of coping were identified. Future steps involve deciding how to organize these families, using their functional homogeneity and distinctiveness, and especially their links to adaptive processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

National annual dioxin emissions estimate for hazardous waste incinerators

Reducing emissions of polychlorinated dibenzo-p-dioxins and dibenzofurans, commonly known as dioxins, is a high priority for environmental regulatory bodies throughout much of the world. In the United States, Section 112 (c)(6) of the Clean Air Act (CAA) requires the Environmental Protection Agency (EPA) to identify and control emissions from sources that are responsible for at least 90% of the overall emissions of seven targeted hazardous air pollutants, including dioxins. On April 19, 1996, the EPA proposed Maximum Achievable Control Technology (MACT) Standards for Hazardous Waste Combustors (HWCs). In that preamble, the EPA estimated annual dioxin emissions from the nation's hazardous waste incinerators (HWIs) to be 79 grams expressed as 2,3,7,8 tetrachloro dibenzo-p-dioxins (TCDD) international toxic equivalents (ITEQs). However, early EPA dioxin emission estimates from medical waste incinerators and cement kilns were significantly overestimated; so, the following independent national dioxin emissions estimate for HWIs was prepared. This estimate corrects the errors in the EPA's HWI emissions database, uses an updated inventory of HWIs in the United States, and applies statistical imputation techniques that take maximum advantage of the limited dioxin emissions data for HWIs.     

An experimental examination of two career interventions for battered women.

The authors tested the effectiveness of 2 group career interventions for 73 battered women who were randomly assigned to 1 of 2 treatment conditions or a wait-list control group. Both interventions included the 5 most effective career intervention components identified by S. D. Brown and N. E. Krane (2000), and 1 of the interventions also was designed to enhance critical consciousness (i.e., empowerment for self-protection and awareness of domestic violence impact; P. Freire, 1970; I. Martín-Baró, 1994). Relative to controls, standard participants had higher career-search self-efficacy, and standard-plus participants had higher critical consciousness at posttest. At follow-up, standard-plus participants had higher critical consciousness scores and made more progress toward goal achievement than standard participants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Retention of aroma compounds in food matrices of similar rheological behaviour and different compositions

Two matrices with a similar rheological behaviour but with a different composition have been developed: one containing carbohydrates (d-glucose, pectin and starch) and in the second one, called complex matrix, a lipid (triolein) was added. The release of six aroma compounds is quantified by using the measurements of partition coefficients at thermodynamic equilibrium. The role of lipid (triolein) on the retention of all the aroma compounds was pointed out. The effect of carbohydrates was more complex: in comparison with water, ethyl hexanoate and trans-2-hexenal were more retained whereas diacetyl, 2-pentanone and cis-3-hexenol were “repulsed” from the matrix. The kinetic study of the release from these matrices had shown a decrease of the initial rate of release by reference with water. From carbohydrates matrix, the decrease of the release for three compounds (ethyl acetate, ethyl hexanoate, 2-pentanone) seemed to arise from the variation of diffusion and/or retention by carbohydrates. For the three other aroma compounds (diacetyl, cis-3-hexenol and trans-2-hexenal) no variation of the initial rate was registered. The comparison of the release rates from carbohydrate and complex matrices indicated the role of lipids and the comparison of the release rates from water and complex matrix showed the combined effects of texture and lipids. The decrease of initial release rate was more important in presence of lipids than in presence of carbohydrates. The most important decrease was observed with the most hydrophobic compound.     

Learning and retention in preclinical and early Alzheimer's disease.

Accelerated forgetting has been proposed as the first sign in preclinical and early Alzheimer's disease (AD). The authors investigated learning and retention in participants who later developed AD with free and cued selective reminding (FCSR; H. Buschke, 1984; E. Grober & H. Buschke, 1987), a test that maximizes learning by inducing deep semantic processing and by controlling study and test conditions. AD patients in the preclinical stage recalled significantly fewer words than did matched control participants, indicating an impairment of learning; nonetheless, patients' retention was identical to that of control participants. A retention deficit was documented 3 years later for AD patients but not for control participants, whose retention was still perfect. Thus, a retention deficit is not present in preclinical AD when hallmark learning deficits can be documented. Detection of preclinical and very early AD may be best accomplished by using robust learning tests that control cognitive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of prosocial, individualistic, and competitive orientations: Theory and preliminary evidence.

The authors adopt an interdependence analysis of social value orientation, proposing that prosocial, individualistic, and competitive orientations are (a) partially rooted in different patterns of social interaction as experienced during the periods spanning early childhood to young adulthood and (b) further shaped by different patterns of social interaction as experienced during early adulthood, middle adulthood, and old age. Congruent with this analysis, results revealed that relative to individualists and competitors, prosocial individuals exhibited greater levels of secure attachment (Studies 1 and 2) and reported having more siblings, especially sisters (Study 3). Finally, the prevalence of prosocials increased—and the prevalence of individualists and competitors decreased—from early adulthood to middle adulthood and old age (Study 4). (PsycINFO Database Record (c) 2010 APA, all rights reserved)