72 research outputs found

    Existing and emerging technologies for measuring stable isotope labelled retinol in biological samples: isotope dilution analysis of body retinol stores

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    This paper discusses some of the recent improvements in instrumentation used for stable isotope tracer measurements in the context of measuring retinol stores, in vivo. Tracer costs, together with concerns that larger tracer doses may perturb the parameter under study, demand that ever more sensitive mass spectrometric techniques are developed. GCMS is the most widely used technique. It has high sensitivity in terms of sample amount and uses high resolution GC, yet its ability to detect low isotope ratios is limited by background noise. LCMSMS may become more accessible for tracer studies. Its ability to measure low level stable isotope tracers may prove superior to GCMS, but it is isotope ratio MS (IRMS) that has been designed specifically for low level stable isotope analysis through accurate analysis of tracer:tracee ratios (the tracee being the unlabelled species). Compound-specific isotope analysis, where GC is interfaced to IRMS, is gaining popularity. Here, individual 13C-labelled compounds are separated by GC, combusted to CO2 and transferred on-line for ratiometric analysis by IRMS at the ppm level. However, commercially-available 13C-labelled retinol tracers are 2 - 4 times more expensive than deuterated tracers. For 2H-labelled compounds, GC-pyrolysis-IRMS has now become more generally available as an operating mode on the same IRMS instrument. Here, individual compounds are separated by GC and pyrolysed to H2 at high temperature for analysis by IRMS. It is predicted that GC-pyrolysis-IRMS will facilitate low level tracer procedures to measure body retinol stores, as has been accomplished in the case of fatty acids and amino acids. Sample size requirements for GC-P-IRMS may exceed those of GCMS, but this paper discusses sample preparation procedures and predicts improvements, particularly in the efficiency of sample introduction

    Two heads are better than one, but how much? Evidence that people's use of causal integration rules does not always conform to normative standards.

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    Many theories of causal learning and causal induction differ in their assumptions about how people combine the causal impact of several causes presented in compound. Some theories propose that when several causes are present, their joint causal impact is equal to the linear sum of the individual impact of each cause. However, some recent theories propose that the causal impact of several causes needs to be combined by means of a noisy-OR integration rule. In other words, the probability of the effect given several causes would be equal to the sum of the probability of the effect given each cause in isolation minus the overlap between those probabilities. In the present series of experiments, participants were given information about the causal impact of several causes and then they were asked what compounds of those causes they would prefer to use if they wanted to produce the effect. The results of these experiments suggest that participants actually use a variety of strategies, including not only the linear and the noisy-OR integration rules, but also averaging the impact of several causes

    Prosocial consequences of interpersonal synchrony: a meta-analysis

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    Abstract. The capacity to establish interpersonal synchrony is fundamental to human beings because it constitutes the basis for social connection and understanding. Interpersonal synchrony refers to instances when the movements or sensations of two or more people overlap in time and form. Recently, the causal influence of interpersonal synchrony on prosociality has been established through experiments. The current meta-analysis is the first to synthesize these isolated and sometimes contradictory experiments. We meta-analyzed 60 published and unpublished experiments that compared an interpersonal synchrony condition with at least one control condition. The results reveal a medium effect of interpersonal synchrony on prosociality with regard to both attitudes and behaviors. Furthermore, experimenter effects and intentionality moderate these effects. We discuss the strengths and limitations of our analysis, as well as its practical implications, and we suggest avenues for future research

    App-Based Coaching to Prevent Addictive Behaviors among Young Adults

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    Abstract: Background: Vocational students have an increased risk to engage in health-risk behaviors compared to same-aged peers. To date, evidence-based digital prevention approaches that address multiple health-risk behaviors are rare. Method: The randomized-controlled trial (RCT) “Prevention of at-risk substance and Internet use disorders among vocational students” (PARI) investigates the efficacy of an app-based prevention approach compared to a waitlist-control condition. The aim is to prevent substance-related and behavioral addictions and improve life skills. An existing app (ready4life) was adapted under consideration of focus groups with teachers, prevention experts, and students. A Delphi expert group rated the quality of the approach. The efficacy of the modified ready4life app is currently being tested in a RCT. The proactive recruitment takes place in German vocational schools. After participating in an app-based screening (T0), participants get individualized feedback and will be cluster-randomized per class to the intervention group (IG; n=1.250) or control group (CG; n=1.250). The IG chooses two out of six modules: Social competence, stress management, cannabis, tobacco, alcohol, social media/gaming. The CG receives information on how to improve health behaviors. Follow-ups are conducted after 6 months (T1) and 12 months (T2). Conclusion: This RCT provides data on a multibehavioral prevention approach for vocational students. Final results are expected in 2023

    COVID-19 Booster Vaccine Acceptance in Ethnic Minority Individuals in the United Kingdom: a mixed-methods study using Protection Motivation Theory

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    Background: Uptake of the COVID-19 booster vaccine among ethnic minority individuals has been lower than in the general population. However, there is little research examining the psychosocial factors that contribute to COVID-19 booster vaccine hesitancy in this population.Aim: Our study aimed to determine which factors predicted COVID-19 vaccination intention in minority ethnic individuals in Middlesbrough, using Protection Motivation Theory (PMT) and COVID-19 conspiracy beliefs, in addition to demographic variables.Method: We used a mixed-methods approach. Quantitative data were collected using an online survey. Qualitative data were collected using semi-structured interviews. 64 minority ethnic individuals (33 females, 31 males; mage = 31.06, SD = 8.36) completed the survey assessing PMT constructs, COVID-19conspiracy beliefs and demographic factors. 42.2% had received the booster vaccine, 57.6% had not. 16 survey respondents were interviewed online to gain further insight into factors affecting booster vaccineacceptance.Results: Multiple regression analysis showed that perceived susceptibility to COVID-19 was a significant predictor of booster vaccination intention, with higher perceived susceptibility being associated with higher intention to get the booster. Additionally, COVID-19 conspiracy beliefs significantly predictedintention to get the booster vaccine, with higher conspiracy beliefs being associated with lower intention to get the booster dose. Thematic analysis of the interview data showed that barriers to COVID-19 booster vaccination included time constraints and a perceived lack of practical support in the event ofexperiencing side effects. Furthermore, there was a lack of confidence in the vaccine, with individuals seeing it as lacking sufficient research. Participants also spoke of medical mistrust due to historical events involving medical experimentation on minority ethnic individuals.Conclusion: PMT and conspiracy beliefs predict COVID-19 booster vaccination in minority ethnic individuals. To help increase vaccine uptake, community leaders need to be involved in addressing people’s concerns, misassumptions, and lack of confidence in COVID-19 vaccination

    Psychological Test Adaptation and Development – How Papers Are Structured and Why

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    This article explains how papers should be structured to guide the preparation of papers to be submitted to Psychological Test Adaptation and Development. Each submission should adhere as strictly as possible to the following structure. If, for any reason, certain aspects cannot be provided, this should be explained and considered in the limitations and recommendations. The outline in Table 1 is followed by a detailed explanation for each section.Peer Reviewe

    Using Differential Item Functioning to Analyze the Domain Generality of a Common Scientific Reasoning Test

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    A significant problem that assessments of scientific reasoning face at the level of higher education is the question of domain generality, that is, whether a test will produce biased results for students from different domains. This study applied three recently developed methods of analyzing differential item functioning (DIF) to evaluate the domain generality assumption of a common scientific reasoning test. Additionally, we evaluated the usefulness of these new, tree- and lasso-based, methods to analyze DIF and compared them with methods based on classical test theory. We gave the scientific reasoning test to 507 university students majoring in physics, biology, or medicine. All three DIF analysis methods indicated a domain bias present in about one-third of the items, mostly benefiting biology students. We did not find this bias by using methods based on classical test theory. Those methods indicated instead that all items were easier for physics students compared to biology students. Thus, the tree- and lasso-based methods provide a clear added value to test evaluation. Taken together, our analyses indicate that the scientific reasoning test is neither entirely domain-general, nor entirely domain-specific. We advise against using it in high-stakes situations involving domain comparisons

    Sports psychiatry: Discipline, areas of activity, collaboration, and training

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    Introduction: Sports psychiatry, a field of psychiatry, is a young medical discipline. The aim of this study was to gauge opinions on the following: sports psychiatry as a specialized subdiscipline, its areas of activity among professionals, the desire for interdisciplinary and interprofessional cooperation, and the need for specific sports psychiatry training. Methods: An online survey was performed to assess the views on sports psychiatry of German-speaking professionals in Switzerland, Germany, and Austria in the field of sports psychiatry. Results: Data from 183 professionals were included in the analysis. Most participants classified sports psychiatry as a field of psychiatry (89%), followed by sports medicine (61%) and child and adolescent psychiatry (49%). Mental health and disorders in competitive and elite sport (94%), sport and exercise for the prevention of and as therapy for mental disorders (84%), and sport-specific mental health problems and disorders in popular sport (80%) were reported by all the participants as areas of activity within sports psychiatry. Most of the participants stated the importance of interdisciplinary and interprofessional collaboration with sports psychiatry’s areas of activity. While 84% of the participants emphasized the necessity for specific training in sports psychiatry, a different picture emerged as to whether such training should be independent or integrated with postgraduate training for psychiatric or sports medicine. Conclusion: The results provide insight into sports psychiatry and its areas of activity and should be used for, and integrated with, the further development of the field

    Continuous-time Latent Markov Factor Analysis for exploring measurement model changes across time

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    Drawing valid inferences about daily or long-term dynamics of psychological constructs (e.g., depression) requires the measurement model (indicating which constructs are measured by which items) to be invariant within persons over time. However, it might be affected by time- or situation-specific artifacts (e.g., response styles) or substantive changes in item interpretation. To efficiently evaluate longitudinal measurement invariance, and violations thereof, we proposed Latent Markov factor analysis (LMFA), which clusters observations based on their measurement model into separate states, indicating which measures are validly comparable. LMFA is, however, tailored to “discretetime” data, where measurement intervals are equal, which is often not the case in longitudinal data. In this paper, we extend LMFA to accommodate unequally spaced intervals. The so-called “continuous-time” (CT) approach considers the measurements as snapshots of continuously evolving processes. A simulation study compares CT-LMFA parameter estimation to its discrete-time counterpart and a depression data application shows the advantages of CT-LMFA
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