125 research outputs found

    On the Simulation of Global Reputation Systems

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    Reputation systems evolve as a mechanism to build trust in virtual communities. In this paper we evaluate different metrics for computing reputation in multi-agent systems. We present a formal model for describing metrics in reputation systems and show how different well-known global reputation metrics are expressed by it. Based on the model a generic simulation framework for reputation metrics was implemented. We used our simulation framework to compare different global reputation systems to find their strengths and weaknesses. The strength of a metric is measured by its resistance against different threat-models, i.e. different types of hostile agents. Based on our results we propose a new metric for reputation systems.Reputation System, Trust, Formalization, Simulation

    UK medical students’ self-reported knowledge and harm assessment of psychedelics and their application in clinical research: a cross-sectional study

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    Objective To capture UK medical students’ self-reported knowledge and harm assessment of psychedelics and to explore the factors associated with support for changing the legal status of psychedelics to facilitate further clinical research. Design Cross-sectional, anonymous online survey of UK medical students using a non-random sampling method. Setting UK medical schools recognised by the General Medical Council. Participants 132 medical students who had spent an average of 3.8 years (SD=1.4; range: 1–6) in medical school. Results Most students (83%) reported that they were aware of psychedelic research and only four participants (3%) said that they were not interested in learning more about this type of research. Although medical students’ harm assessment of psychedelics closely aligned with that of experts, only 17% of students felt well-educated on psychedelic research. Teachings on psychedelics were only rarely encountered in their curriculum (psilocybin: 14.1 (SD=19.9), scale: 0 (never) to 100 (very often)). Time spent at medical schools was not associated with more knowledge about psychedelics (r=0.12, p=0.129). On average, this sample of medical students showed strong support for changing the legal status of psychedelics to facilitate further research into their potential clinical applications (psilocybin: 80.2 (SD=24.8), scale: 0 (strongly oppose) to 100 (strongly support)). Regression modelling indicated that greater knowledge of psychedelics (p<0.001), lower estimated harm scores (p<0.001), more time spent in medical school (p=0.024) and lower perceived effectiveness of non-pharmacological mental health treatments (p=0.044) were associated with greater support for legal status change. Conclusions Our findings reveal a significant interest among UK medical students to learn more about psychedelic research and a strong support for further psychedelic research. Future studies are needed to examine how medical education could be refined to adequately prepare medical students for a changing healthcare landscape in which psychedelic-assisted therapy could soon be implemented in clinical practice

    Evaluating The Ecological Sustainability Of Production Networks – A Data-based Approach

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    The design of global production networks influences the ecological sustainability of manufacturing operations, since it determines the environment with which a production process interacts. Historically sustainability has not been a primary goal for the design of production networks and its evaluation remains a challenge. The multiple goals of sustainability and complex structures of production networks constitute to a high modelling effort that can only be managed with databased solutions. To further decrease the modelling expenditures, the data used in such a solution should be already available or easy to obtain. This paper presents a methodology and data framework to evaluate various ecological sustainability goals, which are impacted by the design of global production networks. The approach is validated with a company that produces electrical appliances

    Software-based Identification of Adaptation Needs in Global Production Networks

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    Internal and external influencing factors force companies to adapt their production networks to changing conditions, which entails a high level of complexity. To be competitive in the future, manufacturing companies have to minimize the required adaptation time between the occurrence of a change and the implementation of an adaptation. While some approaches deal with modelling and evaluating network configuration, there is a lack in identifying the need for adaptation. In practice, the creation of scenarios is often based on the experience and knowledge of the network designer. This paper presents an approach to systematically link perceived key figure changes to possible adaptation alternatives in network configuration. For this purpose, the relevant objects for network adaptations are first defined and adaptation alternatives are systematically described. Subsequently, these are combined with a set of key figures to derive suitable adaptation alternatives depending on their development. The approach is further implemented in a software-based prototype that enables the automated generation of adaptation alternatives in response to perceived changes and provides the user with a listing of possible alternatives prioritized by their utility. The validation with company data demonstrates that by earlier and automated identification of possible configuration adaptations, the adaptation time to changes can be reduced and the generated scenarios are less dependent on the individual experience of the user

    Association between anxiety symptoms and Alzheimer's disease biomarkers in cognitively healthy adults: A systematic review and meta-analysis

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    Objective: Anxiety has been identified as both a risk factor and prodromal symptom for Alzheimer's disease (AD) and related dementias, however, the underlying neurobiological correlates remain unknown. The aim of this systematic review and meta-analysis was to examine the association between anxiety symptoms and two defining markers of AD neuropathology: amyloid-beta (Aβ) and tau. Methods: Systematic literature searches were conducted across 5 databases. Studies investigating the relationship between anxiety and AD neuropathology (i.e., Aβ and/or tau) in cognitively healthy adults were eligible. Where possible, effect sizes were combined across studies, for Aβ and tau separately, using random-effects meta-analyses. Sensitivity analyses were performed to assess whether results differed according to anxiety type (i.e., state and trait) and biomarker assessment modality (i.e., positron emission tomography and cerebrospinal fluid). Results: Twenty-seven studies reporting data from 14 unique cohorts met eligibility criteria. Random-effects meta-analyses revealed no associations between self-reported anxiety symptoms and either Aβ (13 studies, Fisher's z = 0.02, 95% confidence interval [CI] -0.01–0.05, p = 0.194) or tau (4 studies, Fisher's z = 0.04, 95% CI -0.02–0.09, p = 0.235). Results remained unchanged across sensitivity analyses. Conclusions: In cognitively healthy adults, meta-analytic syntheses revealed no associations between anxiety symptoms and either Aβ or tau. There is a critical need, however, for larger studies with follow-up periods to examine the effect of anxiety symptom onset, severity, and chronicity on AD neuropathology. Additionally, further research investigating other potential neurobiological correlates is crucial to advance scientific understanding of the relationship between anxiety and dementia

    Effects of Meditation Training and Non-Native Language Training on Cognition in Older Adults: A Secondary Analysis of a Randomized Clinical Trial

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    IMPORTANCE: Nonpharmacological interventions are a potential strategy to maintain or promote cognitive functioning in older adults. OBJECTIVE: To investigate the effects of 18 months' meditation training and 18 months' non-native language training on cognition in older adults. DESIGN, SETTING, AND PARTICIPANTS: This study was a secondary analysis of the Age-Well trial, an 18-month, observer-masked, randomized clinical trial with 3 parallel arms. Eligible participants were community-dwelling adults aged 65 years and older residing in Caen, France. Participants were enrolled from November 24, 2016, to March 5, 2018, and randomly assigned (1:1:1) to meditation training, non-native language (English) training, or no intervention arms. Final follow-up was completed on February 6, 2020. Data were analyzed between December 2021 and November 2022. INTERVENTIONS: The 18-month meditation and non-native language training interventions were structurally equivalent and included 2-hour weekly group sessions, daily home practice of 20 minutes or longer, and 1 day of more intensive home practice. The no intervention group was instructed not to change their habits and to continue living as usual. MAIN OUTCOMES AND MEASURES: Cognition (a prespecified secondary outcome of the Age-Well trial) was assessed preintervention and postintervention via the Preclinical Alzheimer Cognitive Composite 5 (PACC5), and composites assessing episodic memory, executive function, and attention. RESULTS: Among 137 randomized participants, 2 were excluded for not meeting eligibility criteria, leaving 135 (mean [SD] age, 69.3 [3.8] years; 83 female [61%]) eligible for analysis. One participant among the remaining 135 did not complete the trial. In adjusted mixed effects models, no interaction effects were observed between visit and group for PACC5 (F2,131.39 = 2.58; P = .08), episodic memory (F2,131.60 = 2.34; P = .10), executive function (F2,131.26 = 0.89; P = .41), or attention (F2,131.20 = 0.34; P = .79). Results remained substantively unchanged across sensitivity and exploratory analyses. CONCLUSIONS AND RELEVANCE: In this secondary analysis of an 18-month randomized trial, meditation and non-native language training did not confer salutary cognitive effects. Although further analyses are needed to explore the effects of these interventions on other relevant outcomes related to aging and well-being, these findings did not support the use of these interventions for enhancing cognition in cognitively healthy older adults. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02977819

    Exposure to bioaerosols at open dumpsites: A case study of bioaerosols exposure from activities at Olusosun open dumpsite, Lagos Nigeria

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    Activities associated with the open dumping of municipal solid waste has the potential for greater impact on the environment and public health compared to other forms of waste-to-land treatment of such wastes. However, there is a lack of quantitative data on the exposure to bioaerosols from open dumpsites, hence impeding the development of effective interventions that would reduce the risk of respiratory symptoms among scavengers and waste workers at such dumpsites. This study investigated exposure to bioaerosols at Olusosun open dumpsite, Lagos Nigeria using three methodologies; (1) Conducting a cross-sectional survey on the respiratory health of the population on the dumpsite, (2) Measuring bioaerosol concentrations in the ambient air by measuring four bioaerosols indicator groups (total bacteria, gram-negative bacteria, Aspergillus fumigatus and total fungi) using a Anderson six stage impactor sampler, (3) Measuring activity related exposures to bioaerosols using an SKC button personal sampler. After a cross sectional health survey of 149 participants (waste workers, scavengers, middlemen, food vendors and business owners), smokers reported higher symptoms of chronic cough (21%) and chronic phlegm (15%) compared to non-smokers (chronic cough 15%, chronic phlegm 13%). Years of work > 5 years showed no statistically significant association with chronic phlegm (OR 1.2, 95% CI 0.4–3.4; p > 0.05) or asthma (OR 1.8, 95% CI 0.6–5.2; p > 0.05). At the 95th percentile, the concentration of total bacteria was the highest (2189 CFU/m3), then gram negative bacteria (2188 CFU/m3), total fungi (843 CFU/m3) and Aspergillus fumigatus (441 CFU/m3) after ambient air sampling. A comparison of the data showed that the activity-based sampling (undertaken using body worn personal sampler) had higher bioaerosols concentrations (104 –106 CFU/m3), i.e. 2–3 logs higher than those recorded from static ambient air sampling. Bioaerosol exposure was highest during scavenging activities compared to waste sorting and site supervision. Particle size distributions showed that 41%, 46%, 76% and 63% of total bacteria, gram-negative bacteria, Aspergillus fumigatus and total fungi respectively were of respirable sizes and would therefore be capable of penetrating deep into the respiratory system, posing a greater human health risk. This study has shown that exposure to bioaerosols can be associated with activities undertaken at open dumpsites and may contribute to the high prevalence of the chronic respiratory symptoms among the workers in such environments

    Measuring Psychological Mechanisms in Meditation Practice: Using a Phenomenologically Grounded Classification System to Develop Theory-Based Composite Scores

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    peer reviewedObjectives: Deepening our understanding of the mechanisms by which meditation practices impact well-being and human flourishing is essential for advancing the science of meditation. A recent phenomenologically grounded classification system distinguishes attentional, constructive, and deconstructive forms of meditation based on the psychological mechanisms these practices primarily target or necessitate. Our main aim was to understand whether this theory-based taxonomy could be used as a guiding principle for combining established psychological self-report measures of meditation-related mechanisms into psychometrically adequate composite scores. Methods: We used cross-sectional data to compute meditation composite scores in three independent samples, namely meditation-naïve healthy older adults from the Age-Well trial (n = 135), meditation-naïve older adults with subjective cognitive decline from the SCD-Well trial (n = 147), and healthy long-term meditators (≥ 10,000 h of practice including one 3-year meditation retreat) from the Brain & Mindfulness project (n = 29). The psychometric properties of the composite scores were assessed via floor and ceiling effects, composite intercorrelations, interpretability, and convergent validity in relation to well-being, anxiety, and depression. Results: Three theoretically derived meditation composite scores, reflecting mechanisms involved in attentional, constructive, and deconstructive practices, displayed adequate psychometric properties. Separate secondary confirmatory factor analyses empirically corroborated the theoretically predicted three-factor structure of this classification system. Conclusions: Complementing data-driven approaches, this study offers preliminary support for using a theoretical model of meditation-related mechanisms to create empirically meaningful and psychometrically sound composite scores. We conclude by suggesting conceptual and methodological considerations for future research in this area.MEDIT-AGEING - Investigating the impact of meditation training on mental health and wellbeing in the ageing populationBRAINANDMINDFULNESS - Impact of Mental Training of Attention and Emotion Regulation on Brain and Behavior: Implications for Neuroplasticity, Well-Being and Mindfulness Psychotherapy Research

    Hemiptera records from Lake Spechtensee and from Southern Styria (Austria)

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    Hemiptera records gained in July 2015 in course of the 7th European Hemiptera Congress in Styria are presented. In total, 144 Auchenorrhyncha, 143 Heteroptera, 13 Psylloidea and 2 Aphididae species were collected. Ribautodelphax imitans (Delphacidae), Eurhadina saageri (Cicadellidae), Notonecta maculata (Notonectidae), Notonecta meridionalis (Notonectidae) and Polymerus cognatus (Miridae) are new records for Styria

    Effects of a mindfulness-based intervention and a health self-management programme on psychological well-being in older adults with subjective cognitive decline: Secondary analyses from the SCD-Well randomised clinical trial.

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    peer reviewed[en] OBJECTIVES: Older adults with subjective cognitive decline (SCD) recruited from memory clinics have an increased risk of developing dementia and regularly experience reduced psychological well-being related to memory concerns and fear of dementia. Research on improving well-being in SCD is limited and lacks non-pharmacological approaches. We investigated whether mindfulness-based and health education interventions can enhance well-being in SCD. METHODS: The SCD-Well trial (ClinicalTrials.gov: NCT03005652) randomised 147 older adults with SCD to an 8-week caring mindfulness-based approach for seniors (CMBAS) or an active comparator (health self-management programme [HSMP]). Well-being was assessed at baseline, post-intervention, and 6-month post-randomisation using the Psychological Well-being Scale (PWBS), the World Health Organisation's Quality of Life (QoL) Assessment psychological subscale, and composites capturing meditation-based well-being dimensions of awareness, connection, and insight. Mixed effects models were used to assess between- and within-group differences in change. RESULTS: CMBAS was superior to HSMP on changes in connection at post-intervention. Within both groups, PWBS total scores, psychological QoL, and composite scores did not increase. Exploratory analyses indicated increases in PWBS autonomy at post-intervention in both groups. CONCLUSION: Two non-pharmacological interventions were associated with only limited effects on psychological well-being in SCD. Longer intervention studies with waitlist/retest control groups are needed to assess if our findings reflect intervention brevity and/or minimal base rate changes in well-being
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