Production of biogenic amines by lactic acid bacteria and bifidobacteria isolated from dairy products and beer

The aim was to monitor production of eight biogenic amines (BAs) (histamine, tyramine (TYR), tryptamine, putrescine, cadaverine (CAD), phenylethylamine, spermine and spermidine) by selected 81 lactic acid bacteria (LAB) strains: Lactobacillus, Lactococcus, Leuconostoc, Enterococcus, Pediococcus, Tetragenococcus and Bifidobacterium. The tested LAB and bifidobacteria were isolated from dairy products and beer. The decarboxylase activity of the micro‐organisms was studied in growth medium after cultivation. The activity was monitored by HPLC after the pre‐column derivatisation with dansylchloride. Fifty LAB showed decarboxylase activity. Thirty‐one strains produced low concentrations of CAD (≤10 mg L^?1). Almost 70% of beer isolates generated higher amounts of TYR (≤3000 mg L^?1). Most of the tested LAB demonstrated decarboxylase activity. The above micro‐organisms can contribute to the increase of content of BAs in dairy products or beer and thereby threaten food safety and health of consumers. Production of BAs even by the representatives of some probiotic strains (Bifidobacterium and Lactobacillus rhamnosus) was detected in this research. This study has also proved that contaminating LAB can act as sources of higher amounts of CAD and TYR in beer.     

To Change or Not To Change: How Regulatory Focus Affects Change in Dyadic Decision‐Making

Successful innovation requires teams to embrace and enact change. However, team members often differ in their preferences for change. We examine how regulatory focus affects dyadic teams’ tendencies to enact change across an array of repeated brand management decisions. Understanding such tendencies is important, since the innovation process is characterized by a series of investment decisions typically made by teams, yet prone to significant biases. Regulatory focus theory provides a framework for understanding the dominant motivations driving decision‐making during goal pursuit. It argues that individuals operate under either a promotion or prevention focus, influencing preferences for stability vs. change. We develop a set of hypotheses regarding regulatory focus match vs. mismatch in teams and their effects on the relative tendency to enact change in decision‐making. In the context of dyads involved in a complex management simulation consisting of multiple decision cycles, we empirically demonstrate that a promotion focus match is associated with greater levels of change in decisions than a prevention focus match, regardless of the type of goal pursuit strategy prescribed to dyads. Under regulatory focus mismatch, however, dyads are guided by the goal pursuit strategy (vigilant vs. eager) provided to them, which in turn informs their propensity to implement change.

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On the limiting factors of the critical current density in high-T c superconducting ceramics

The temperature dependence of the critical current density at high temperatures and in weak applied magnetic field for YBa₂Cu₃O_7?y ceramic samples with a pronounced granular character is analyzed. The experimental results can be explained in terms of thermally activated motion of the intergrain Josephson vortices at grain boundaries, which may be an indication that the actual limiting factor for the critical current density in ceramic samples results from a weak pinning force density for the intergrain vortices rather than from the weak-link quenching.     

Rorschach revisited: A new look at an old test.

Two control samples (21 and 27 college students) and a sample of 21 short-term psychiatric patients (aged 21-26 yrs) scaled all pairs of Rorschach inkblots for perceived similarity. Data were analyzed using J. D. Carroll and C. C. Chang's individual scaling (INDSCAL) model, which resulted in a good fit in 2 dimensions. These 2 dimensions were interpreted as a dimension of color and 1 of form ("twoness"), and empirically validated in a 2nd study, using 2 groups of controls (20 and 33 college students) and 6 short-term schizophrenic patients. It was also found that the saliences estimated by INDSCAL for each S formed 3 virtually nonoverlapping distributions. This implies a possible use of the method within a diagnostic context. (42 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A psychosocial model of sun protection and sunbathing in young women: The impact of health beliefs, attitudes, norms, and self-efficacy for sun protection.

A psychosocial model of sun protection and sunbathing as distinct behaviors was developed on 202 young Caucasian women and replicated in an independent sample (n?=?207). Proximal outcomes were intention to sun protect and intention to sunbathe; distal outcomes included sun protection and sunbathing behavior measured 5 months later. Objective risk for skin cancer plus 4 classes of psychosocial variables (sun-protective health beliefs, self-efficacy for sun protection, attitudes toward sunbathing, and norms for sunbathing and sun protection) served as predictors. Sun-protective norms and self-efficacy for sun protection predicted only intention to sun protect; sunbathing norms predicted only intention to sunbathe. Susceptibility and advantages of tanning predicted both intention constructs, which, in turn, predicted behavior. These findings distinguish sun protection from sunbathing and provide a basis for intervention design. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

ARADISH - Development of a Standardized Plant Growth Chamber for Experiments in Gravitational Biology Using Ground Based Facilities

Plant development strongly relies on environmental conditions. Growth of plants in Biological Life Support Systems (BLSS), which are a necessity to allow human survival during long-term space exploration missions, poses a particular problem for plant growth, as in addition to the traditional environmental factors, microgravity (or reduced gravity such as on Moon or Mars) and limited gas exchange hamper plant growth. Studying the effects of reduced gravity on plants requires real or simulated microgravity experiments under highly standardized conditions, in order to avoid the influence of other environmental factors. Analysis of a large number of biological replicates, which is necessary for the detection of subtle phenotypical differences, can so far only be achieved in Ground Based Facilities (GBF). Besides different experimental conditions, the usage of a variety of different plant growth chambers was a major factor that led to a lack of reproducibility and comparability in previous studies. We have developed a flexible and customizable plant growth chamber, called ARAbidopsis DISH (ARADISH), which allows plant growth from seed to seedling, being realized in a hydroponic system or on Agar. By developing a special holder, the ARADISH can be used for experiments with Arabidopsis thaliana or a plant with a similar habitus on common GBF hardware, including 2D clinostats and Random Positioning Machines (RPM). The ARADISH growth chamber has a controlled illumination system of red and blue light emitting diodes (LED), which allows the user to apply defined light conditions. As a proof of concept we tested a prototype in a proteomic experiment in which plants were exposed to simulated microgravity or a 90° stimulus. We optimized the design and performed viability tests after several days of growth in the hardware that underline the utility of ARADISH in microgravity research.     

Young women's condom use: The influence of acceptance of sexuality, control over the sexual encounter, and perceived susceptibility to common STDs.

A comprehensive model of the determinants of condom use among young women was developed, tested, and replicated, with longitudinal follow-up to assess predictive utility of the model for condom use over time. Participants in Study 1 and Study 2 were 198 female undergraduates (mean age, 18.6 years) and 238 female undergraduates (mean age, 19.1 years), respectively. Acceptance of sexuality and control over the sexual encounter were related to a multidimensional measure of condom use self-efficacy, which predicted condom use intentions. Perceived susceptibility to STDs was both directly related to intentions and indirectly related through perceived benefits and attitudes about condom use. Intentions predicted subsequent reports of condom use. The model suggests foci for condom use interventions for young women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Health beliefs and compliance with mammography-screening recommendations in asymptomatic women.

The utility of the health belief model (HBM) for predicting compliance with the American Cancer Society recommendations for mammography screening over and above demographics, knowledge, physician input, and objective risk for breast cancer was assessed. In all, 615 predominantly middle-class White women (aged 35–92 yrs) were surveyed from 1987 to 1989. A multiple indicator measurement model of the HBM constructs of perceived susceptibility, severity, benefits, and barriers was verified with confirmatory factor analysis. Physician input alone accounted for 25% of the variance in compliance, and HBM constructs alone, 16%. HBM constructs accounted for 7% additional variance in compliance beyond all other predictors and thus may be a fruitful focus for interventions to increase screening rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Doctoral training in statistics, measurement, and methodology in psychology: Replication and extension of Aiken, West, Sechrest, and Reno's (1990) survey of PhD programs in North America.

In a survey of all PhD programs in psychology in the United States and Canada, the authors documented the quantitative methodology curriculum (statistics, measurement, and research design) to examine the extent to which innovations in quantitative methodology have diffused into the training of PhDs in psychology. In all, 201 psychology PhD programs (86%) participated. This survey replicated and extended a previous survey (L. S. Aiken, S. G. West, L. B. Sechrest, & R. R. Reno, 1990), permitting examination of curriculum development. Most training supported laboratory and not field research. The median of 1.6 years of training in statistics and measurement was mainly devoted to the modally 1-year introductory statistics course, leaving little room for advanced study. Curricular enhancements were noted in statistics and to a minor degree in measurement. Additional coverage of both fundamental and innovative quantitative methodology is needed. The research design curriculum has largely stagnated, a cause for great concern. Elite programs showed no overall advantage in quantitative training. Forces that support curricular innovation are characterized. Human capital challenges to quantitative training, including recruiting and supporting young quantitative faculty, are discussed. Steps must be taken to bring innovations in quantitative methodology into the curriculum of PhD programs in psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)