246 research outputs found

    Formation of Esters by Yeast. II. Investigations with Cellular Suspensions of Hansenula Anomala

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    The position of authenticity within extant models of personality.

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    The aim of the current study was to explore where authenticity, derived from the humanistic tradition of psychology, was positioned within a number of extant models of personality. Exploratory and Confirmatory Factor Analysis of data from four samples (total N = 1286) suggested that authenticity can be considered as loading on the Honesty–Humility factor of personality. These findings are discussed in terms of the wider theoretical overlaps between Honesty–Humility and psychological functioning as emphasised by the humanistic tradition of psychology

    Trait urgency and gambling problems in young people by age: The mediating role of decision-making processes

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    Although the personality trait of urgency has been linked to problem gambling, less is known about psychological mechanisms that mediate the relationship between urgency and problem gambling. One individual variable of potential relevance to impulsivity and addictive disorders is age. The aims of this study were to examine: (i) a theoretical model associating urgency and gambling problems, (ii) the mediating effects of decision-making processes (operationalized as preference for small/immediate rewards and lower levels of deliberative decision-making); and (iii) age differences in these relationships. Participants comprised 986 students (64% male; mean age=19.51 years; SD=2.30) divided into three groups: 16-17 years, 18-21 years, and 22-25 years. All participants completed measures of urgency, problem gambling, and a delay-discounting questionnaire involving choices between a smaller amount of money received immediately and a larger amount of money received later. Participants were also asked to reflect on their decision-making process. Compared to those aged 16-17 years and 22-25 years, participants aged 18-21 years had a higher level of gambling problems and decreased scores on lower levels of deliberative decision-making. Higher levels of urgency were associated with higher levels of gambling problems. The association was mediated by a lower level of deliberative decision-making and preference for an immediate/small reward. A distinct pathway was observed for lower levels of deliberative decision-making. Young people who tend to act rashly in response to extreme moods, had lower levels of deliberative decision-making, that in turn were positively related to gambling problems. This study highlights unique decision-making pathways through which urgency trait may operate, suggesting that those developing prevention and/or treatment strategies may want to consider the model’s variables, including urgency, delay discounting, and deliberative decision-making

    Post-traumatic growth following acquired brain injury: a systematic review and meta-analysis

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    peer-reviewedThe idea that acquired brain injury (ABI) caused by stroke, hemorrhage, infection or traumatic insult to the brain can result in post-traumatic growth (PTG) for individuals is increasingly attracting psychological attention. However, PTG also attracts controversy as a result of ambiguous empirical findings. The extent that demographic variables, injury factors, subjective beliefs, and psychological health are associated with PTG following ABI is not clear. Consequently, this systematic review and meta-analysis explores the correlates of variables within these four broad areas and PTG. From a total of 744 published studies addressing PTG in people with ABI, eight studies met inclusion criteria for detailed examination. Meta-analysis of these studies indicated that growth was related to employment, longer education, subjective beliefs about change post-injury, relationship status, older age, longer time since injury, and lower levels of depression. Results from homogeneity analyses indicated significant inter-study heterogeneity across variables. There is general support for the idea that people with ABI can experience growth, and that various demographics, injury-related variables, subjective beliefs and psychological health are related to growth. The contribution of social integration and the forming of new identities post-ABI to the experience of PTG is explored. These meta-analytic findings are however constrained by methodological limitations prevalent in the literature. Clinical and research implications are discussed with specific reference to community and collective factors that enable PTG

    Overview of Classical Test Theory and Item Response Theory for the Quantitative Assessment of Items in Developing Patient-Reported Outcomes Measures

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    BackgroundThe US Food and Drug Administration's guidance for industry document on patient-reported outcomes (PRO) defines content validity as "the extent to which the instrument measures the concept of interest" (FDA, 2009, p. 12). According to Strauss and Smith (2009), construct validity "is now generally viewed as a unifying form of validity for psychological measurements, subsuming both content and criterion validity" (p. 7). Hence, both qualitative and quantitative information are essential in evaluating the validity of measures.MethodsWe review classical test theory and item response theory (IRT) approaches to evaluating PRO measures, including frequency of responses to each category of the items in a multi-item scale, the distribution of scale scores, floor and ceiling effects, the relationship between item response options and the total score, and the extent to which hypothesized "difficulty" (severity) order of items is represented by observed responses.ResultsIf a researcher has few qualitative data and wants to get preliminary information about the content validity of the instrument, then descriptive assessments using classical test theory should be the first step. As the sample size grows during subsequent stages of instrument development, confidence in the numerical estimates from Rasch and other IRT models (as well as those of classical test theory) would also grow.ConclusionClassical test theory and IRT can be useful in providing a quantitative assessment of items and scales during the content-validity phase of PRO-measure development. Depending on the particular type of measure and the specific circumstances, the classical test theory and/or the IRT should be considered to help maximize the content validity of PRO measures

    Differential effects of Atomoxetine on executive functioning and lexical decision in Attention-Deficit/Hyperactivity Disorder and Reading Disorder

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    Objective: The effects of a promising pharmacological treatment for attention-deficit/hyperactivity disorder (ADHD), atomoxetine, were studied on executive functions in both ADHD and reading disorder (RD) because earlier research demonstrated an overlap in executive functioning deficits in both disorders. In addition, the effects of atomoxetine were explored on lexical decision. Methods: Sixteen children with ADHD, 20 children with ADHD + RD, 21 children with RD, and 26 normal controls were enrolled in a randomized placebo-controlled crossover study. Children were measured on visuospatial working memory, inhibition, and lexical decision on the day of randomization and following two 28-day medication periods. Results: Children with ADHD + RD showed improved visuospatial working memory performance and, to a lesser extent, improved inhibition following atomoxetine treatment compared to placebo. No differential effects of atomoxetine were found for lexical decision in comparison to placebo. In addition, no effects of atomoxetine were demonstrated in the ADHD and RD groups. Conclusion: Atomoxetine improved visuospatial working memory and to a lesser degree inhibition in children with ADHD + RD, which suggests differential developmental pathways for co-morbid ADHD + RD as compared to ADHD and RD alone

    Exploring the constraint profile of winter sports resort tourist segments

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    Many studies have confirmed the importance of market segmentation both theoretically and empirically. Surprisingly though, no study has so far addressed the issue from the perspective of leisure constraints. Since different consumers face different barriers, we look at participation in leisure activities as an outcome of the negotiation process that winter sports resort tourists go through, to balance between related motives and constraints. This empirical study reports the findings on the applicability of constraining factors in segmenting the tourists who visit winter sports resorts. Utilizing data from 1,391 tourists of winter sports resorts in Greece, five segments were formed based on their constraint, demographic and behavioral profile. Our findings indicate that such segmentation sheds light on factors that could potentially limit the full utilization of the market. To maximize utilization, we suggest customizing marketing to the profile of each distinct winter sports resort tourist segment that emerge

    Rapid Sampling of Molecules via Skin for Diagnostic and Forensic Applications

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    Skin provides an excellent portal for diagnostic monitoring of a variety of entities; however, there is a dearth of reliable methods for patient-friendly sampling of skin constituents. This study describes the use of low-frequency ultrasound as a one-step methodology for rapid sampling of molecules from the skin. Sampling was performed using a brief exposure of 20 kHz ultrasound to skin in the presence of a sampling fluid. In vitro sampling from porcine skin was performed to assess the effectiveness of the method and its ability to sample drugs and endogenous epidermal biomolecules from the skin. Dermal presence of an antifungal drug—fluconazole and an abused substance, cocaine—was assessed in rats. Ultrasonic sampling captured the native profile of various naturally occurring moisturizing factors in skin. A high sampling efficiency (79 ± 13%) of topically delivered drug was achieved. Ultrasound consistently sampled greater amounts of drug from the skin compared to tape stripping. Ultrasonic sampling also detected sustained presence of cocaine in rat skin for up to 7 days as compared to its rapid disappearance from the urine. Ultrasonic sampling provides significant advantages including enhanced sampling from deeper layers of skin and high temporal sampling sensitivity
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