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Abstract: Background and aims: Despite the last decade’s significant development in the scientific study of work addiction/workaholism, this area of research is still facing a fundamental challenge, namely the need for a valid and reliable measurement tool that shows cross-cultural invariance and, as such, allows for worldwide studies on this phenomenon. Methods: An initial 16-item questionnaire, developed within an addiction framework, was administered alongside job stress, job satisfaction, and self-esteem measures in a total sample of 31,352 employees from six continents and 85 cultures (63.5% females, mean age of 39.24 years). Results: Based on theoretical premises and psychometric testing, the International Work Addiction Scale (IWAS) was developed as a short measure representing essential features of work addiction. The seven-item version (IWAS-7), covering all seven components of work addiction, showed partial scalar invariance across 81 cultures, while the five-item version (IWAS-5) showed it across all 85 cultures. Higher levels of work addiction on both versions were associated with higher job stress, lower job satisfaction, and lower self-esteem across cultures. The optimal cut-offs for the IWAS-7 (24 points) and IWAS-5 (18 points) were established with an overall accuracy of 96% for both versions. Discussion and conclusions: The IWAS is a valid, reliable, and short screening scale that can be used in different cultures and languages, providing comparative and generalizable results. The scale can be used globally in clinical and organizational settings, with the IWAS-5 being recommended for most practical and clinical situations. This is the first study to provide data supporting the hypothesis that work addiction is a universal phenomenon worldwide.
Keywords: workaholism, validation, cross-cultural studies, Bergen Work Addiction Scale, compulsive overworking, cross-cultural, work addiction
Published in DKUM: 29.08.2025; Views: 0; Downloads: 1
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Abstract: With computational modeling of lyophilization in vials, the pressure coupling between the sublimation front and the drying chamber has traditionally been calculated using a simplified mass transfer resistance model in the form of a model, which takes into account the headspace and the stopper in a simplified way. In developing a 3D CFD-based digital twin of lyophilization in vials, a need arises for a mass flow rate-dependent vial headspace/stopper model, as it enables a more accurate calculation of the pressure conditions above the shelf as well as pressure conditions directly at the sublimation front, the latter directly affecting the sublimation mass transfer rate as well as the temperature inside the product, which is crucial for determining the risk of product collapse. The local pressure variations at a shelf level affect the heat transfer conditions due to heat conduction in the low pressure environment of the drying chamber. In the present work the development of a coupled multilevel vial lyophilization model for the freeze-drying of vials is reported, with the time-dependent 1D heat and mass transfer model at the vial level coupled with the time-dependent 3D low-pressure CFD model of the flow of the water vapor–air mixture in the drying chamber heated by the shelves. A direct pressure coupling between the sublimation front and the drying chamber space in form of vial type specific headspace/stopper resistance model is implemented. The developed multilevel lyophilization model is used to study the pressure build-up above the shelf and the headspace of the vial and its influence on the product temperature at the bottom of the vial using simulations carried out for different chamber pressures (6 Pa and 22 Pa), shelf temperatures (−20 oC and +10 oC) and vial types (10R and 15R). By implementing previously developed vial headspace/stopper pressure resistance models, the computational results show that the pressure build-up above the shelf and vial headspace significantly affect the product temperature at the bottom of the vial, especially at low chamber pressures ( Pa) and small gap sizes between the rubber stopper and the shelf above it. The increased pressure outside the vial leads also to higher heat transfer by conduction, which is particularly pronounced at the central shelf positions and within smaller shelf gaps. These results underline the importance of using a coupled multilevel model when analyzing the relationship between the local pressure variations above the shelf and their direct influence on product drying conditions, further improving the predictive capabilities of CFD based multilevel lyophilization models, especially with respect to detecting the product collapse temperature.
Keywords: freeze-drying, conjugate heat and mass transfer, computational fluid dynamics, multi-scale modeling
Published in DKUM: 17.06.2025; Views: 0; Downloads: 13
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Abstract: This paper quantifies the correlation between U.S. season average prices for hops with U.S. hop stocks and U.S. hop hectarage. The Hop Equilibrium Ratio, a measure of the supply/demand relationship for U.S. hops, was introduced. Through the Bayesian inference method, the authors used these data to calculate the effect an incremental change to one metric had on the probability of directional changes of future U.S. season average prices (SAP). Between 2010 and 2020, the dominance of proprietary varieties created unprecedented cartel-like powers offering opportunities for supply- and price-management. Research results will enable more accurate forecasting and greater price stability in the hop industry.
Keywords: alpha-acid, Bayesian theorem, brewing industry, economies of scale, equillbrium, hop market
Published in DKUM: 28.01.2025; Views: 0; Downloads: 31
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Abstract: Aims: Understanding fine-grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine-grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location: Palaearctic biogeographic realm. Methods: We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m2 and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results: Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi-natural) grasslands and natural grasslands are the richest vegetation type. The open-access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions: The GrassPlot Diversity Benchmarks provide high-quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation-plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology.
Keywords: benchmark, bryophyte, fine-grain biodiversity, grassland, GrassPlot Diversity Explorer, lichen, open habitat, Palaearctic, scale dependence, species–area relationship, vascular plant, vegetation plot
Published in DKUM: 07.08.2024; Views: 88; Downloads: 10
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Abstract: Objective While other models focus more on disease and pathophysiology, the biopsychosocial approach emphasises the importance of human health and disease in their fullest contexts. If we are to gain an insight into physical and psychological health needs, and address them quickly and adequately, it is important that we recognise them already at the family practice stage. An approach that assesses needs at patient level could also be seen as patient-centred care, which is one of the key elements of high-quality care. To the best of our knowledge, no scale for measuring the biopsychosocial approach of family physicians has yet been developed. Design The aim of this study was to develop and validate a scale that measures the biopsychosocial approach of family physicians to their patients through the Delphi and validation process. Setting The scale was developed through the Delphi study and validated by means of significant statistical methods. Pearson’s correlation coefficient, Cronbach’s alpha, the intracorrelation coefficient, the Spearman-Brown coefficient and exploratory factor analysis were applied. Participants Five family physicians took part in a brainstorming process and 24 family medicine experts took part in the Delphi study. For the first part of the validation process, there were 31 family medicine trainees in the first group and 32 in the second group. For the last part of the validation process, 164 family physicians completed the scale. Result Through the Delphi study, 39 final items covering three areas within the biopsychosocial approach were identified. Construct validity was high, with positive linear correlation and good face validity. The intraclass correlation coefficient for test–retest reliability was 0.862. The Spearman-Brown coefficient was the highest (0.931) on an even and odd division. Factor rotation showed that three factors on 35 items explained 39.5% of variances. The final internal consistency on 35 items was 0.911. Conclusion The developed scale measures the biopsychosocial dimension of family physicians’ work with high Cronbach’s alpha measures and good validity.
Keywords: scale for measuring biopsychosocial approach, family physicians, patients, development, validation
Published in DKUM: 26.06.2024; Views: 147; Downloads: 18
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