19 research outputs found

    Fully Dynamic High–Resolution Model for Dispersion of Icelandic Airborne Mineral Dust

    Get PDF
    Icelandic topsoil sediments, as confirmed by numerous scientific studies, represent the largest and the most important European source of mineral dust. Strong winds, connected with the intensive cyclonic circulation in the North Atlantic, induce intense emissions of mineral dust from local sources all year and carry away these fine aerosol particles for thousands of kilometers. Various impacts of airborne mineral dust particles on local air quality, human health, transportation, climate and marine ecosystems motivated us to design a fully dynamic coupled atmosphere–dust numerical modelling system in order to simulate, predict and quantify the Icelandic mineral dust process including: local measurements and source specification over Iceland. In this study, we used the Dust Regional Atmospheric Model (DREAM) with improved Icelandic high resolution dust source specification and implemented spatially variable particle size distribution, variable snow cover and soil wetness. Three case studies of intense short- and long-range transport were selected to evaluate the model performance. Results demonstrated the model’s capability to forecast major transport features, such as timing, and horizontal and vertical distribution of the processes. This modelling system can be used as an operational forecasting system, but also as a reliable tool for assessing climate and environmental Icelandic dust impacts. © 2022 by the authors

    The International Work Addiction Scale (IWAS): A screening tool for clinical and organizational applications validated in 85 cultures from six continents

    Get PDF
    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.fals

    Gonadectomy in conditions affecting sex development: a registry-based cohort study

    Get PDF
    Objectives To determine trends in clinical practice for individuals with DSD requiring gonadectomy. Design Retrospective cohort study. Methods Information regarding age at gonadectomy according to diagnosis; reported sex; time of presentation to specialist centre; and location of centre from cases reported to the International DSD Registry and who were over 16 years old in January 2019. Results Data regarding gonadectomy were available in 668 (88%) individuals from 44 centres. Of these, 248 (37%) (median age (range) 24 (17, 75) years) were male and 420 (63%) (median age (range) 26 (16, 86) years) were female. Gonadectomy was reported from 36 centres in 351/668 cases (53%). Females were more likely to undergo gonadectomy (n = 311, P < 0.0001). The indication for gonadectomy was reported in 268 (76%). The most common indication was mitigation of tumour risk in 172 (64%). Variations in the practice of gonadectomy were observed; of the 351 cases from 36 centres, 17 (5%) at 9 centres had undergone gonadectomy before their first presentation to the specialist centre. Median age at gonadectomy of cases from high-income countries and low-/middle-income countries (LMIC) was 13.0 years (0.1, 68) years and 16.5 years (1, 28), respectively (P < 0.0001) with the likelihood of long-term retention of gonads being higher in LMIC countries. Conclusions The likelihood of gonadectomy depends on the underlying diagnosis, sex of rearing and the geographical setting. Clinical benchmarks, which can be studied across all forms of DSD will allow a better understanding of the variation in the practice of gonadectomy

    Preparation and polarographic half-wave potentials of neopentylhydroquinones

    No full text

    Reaction of 20-lupanol derivatives with lead tetraacetate

    No full text

    Neurobiological aspects of depressive disorder and antidepressant treatment: role of glia

    No full text
    Depression is a complex disorder related to chronic inflammatory processes, chronic stress changes and a hippocampal response. There is a increasing knowledge about the role of glial cells in nutrient supply to neurons, maintenance of synaptic contacts and tissue homeostasis within the CNS. Glial cells, viewed in the past as passive elements with a limited influence on neuronal function, are becoming recognized as active partners of neurons and are starting to be discussed as a possible therapeutic target. Their role in the pathogenesis of depressive disorders is also being reconsidered. Attention is devoted to studies of the different types of antidepressants and their effects on transmembrane signaling, including levels of α subunits of G proteins in C6 glioma cells in vitro as a model of postsynaptic changes in vivo. These models indicate similarities in antidepressant effects on G proteins of brain cells and effector cells of natural immunity, natural killers and granulocytes. Thus, an antidepressant response can exhibit certain common characteristics in functionally different systems which also participate in disease pathogenesis. There are, however, differences in the astrocyte G-protein responses to antidepressant treatment, indicating that antidepressants differ in their effect on glial signalization. Today mainstream approach to neurobiological basis of depressive disorders and other mood illnesses is linked to abnormalities in transmembrane signal transduction via G-protein coupled receptors. Intracellular signalization cascade modulation results in the activation of transcription factors with subsequent increased production of a wide array of products including growth factors and to changes in cellular activity and reactivity.</jats:p

    The patchwork loess of Central Asia: Implications for interpreting aeolian dynamics and past climate circulation in piedmont regions

    No full text
    ABSTRACTReconstruction of mass accumulation rates (MARs) in loess deposits are widely used for interpreting long‐term aeolian transport and climate dynamics in terrestrial environments. However, these interpretations are often driven by a preponderance of reconstructions from individual or selected sites, which can bias our understanding of past climate, especially in the absence of other proxy information. Recent studies on MARs from multiple loess sites in Arid Central Asia (ACA) reveal disparities in the timing of peaks in accumulation between sites, as well as asynchronies with loess flux in the Chinese Loess Plateau (CLP). We investigate this issue by (1) dating five new sites from the western Ili Basin, therefore extending the spatial cover of loess chronologies across ACA and (2) combining that with MARs from &gt;30 sites across ACA and the CLP over the last 60 ka. Our results indicate spatio‐temporal inhomogeneity in the timing and rate of loess deposition across the ACA, and highlight the importance of interrogating local and regional influences on dust supply and transport. Our synthesis of MARs from ACA and the CLP suggests that the timing of peak dust flux as an indicator of large‐scale climate dynamics is best derived from an aggregate of sites; this removes site‐specific bias where local processes or topographic settings outweigh the climate signature.L Lisá acknowledges the support of internal program No. RVO67985831 of the Institute of Geology CAS, Prague and OP RDE, MEYS under the project ‘Ultra‐trace isotope research in social and environmental studies using accelerator mass spectrometry’, Reg. No. CZ.02.1.01/0.0/0.0/16_019/0000728.This study was funded by an independent Max Planck Research Group awarded by the Max Planck Society to KE Fitzsimmons

    The patchwork loess of Central Asia: Implications for interpreting aeolian dynamics and past climate circulation in piedmont regions

    No full text
    Reconstruction of mass accumulation rates (MARs) in loess deposits are widely used for interpreting long-term aeolian transport and climate dynamics in terrestrial environments. However, these interpretations are often driven by a preponderance of reconstructions from individual or selected sites, which can bias our understanding of past climate, especially in the absence of other proxy information. Recent studies on MARs from multiple loess sites in Arid Central Asia (ACA) reveal disparities in the timing of peaks in accumulation between sites, as well as asynchronies with loess flux in the Chinese Loess Plateau (CLP). We investigate this issue by (1) dating five new sites from the western Ili Basin, therefore extending the spatial cover of loess chronologies across ACA and (2) combining that with MARs from >30 sites across ACA and the CLP over the last 60 ka. Our results indicate spatio-temporal inhomogeneity in the timing and rate of loess deposition across the ACA, and highlight the importance of interrogating local and regional influences on dust supply and transport. Our synthesis of MARs from ACA and the CLP suggests that the timing of peak dust flux as an indicator of large-scale climate dynamics is best derived from an aggregate of sites; this removes site-specific bias where local processes or topographic settings outweigh the climate signature.Research Group for Terrestrial Palaeoclimates Max Planck Institute for ChemistryDepartment of Geosciences University of Tübingen, Schnarrenbergstrasse 94-96Institute of Geology Czech Academy of SciencesNuclear Physics Institute of the Czech Academy of Sciences CRL Radiocarbon Laboratory, Na Truhlářce 39/64Instituto de Geociências e Ciências Exatas Universidade Estadual Paulista (UNESP)Institute of Geological Sciences K. Satpaeva Ministry for Education and Science of the Republic of KazakhstanInstituto de Geociências e Ciências Exatas Universidade Estadual Paulista (UNESP

    Changes in cell cycle and chromatin distribution in C6 glioma cells treated by dibutyryl cyclic AMP.

    No full text
    C6 glioma cells in culture were treated with 1 mM dibutyryl cyclic AMP (Db-cAMP) for 5, 8, 24 and 72 h. The cells were labelled with [3H]-thymidine before either the end, or the beginning, of the Db-cAMP treatment. The cell cycle passage was monitored by the simultaneous determination of DNA content and DNA synthesis in propidium iodide stained autoradiograms. The data revealed an early (t less than or equal to 3-8 h) and moderate inhibitory effect of Db-cAMP on all phases of the cell cycle except mitosis; some cells (2%) were completely blocked in the S phase. Later (8 less than t less than 24-72 h), the cycling of a substantial part of the population became inhibited in G1 phase. Microdensitometric texture analysis of Feulgen-stained nuclei, performed 24 h after administration of Db-cAMP, showed a higher inhomogeneity of the DNA distribution in cell nuclei, caused by the condensation of a part of the chromatin. This may reflect either changes in genome expression taking part in the process of cAMP induced differentiation or transit of some cells into quiescent G0 or S0 phases
    corecore