244 research outputs found
(3S,11Z)-14,16-Dihydroxy-3-methyl-3,4,5,6,9,10-hexahydro-1H-2-benzoxacyclotetradecine-1,7(8H)-dione (cis-zearalenone): a redetermination
The title compound, also known as cis-zearalenone (cis-ZEN), C18H22O5, has already been reported elsewhere [Griffin et al. (1981 ▶). ACA Ser.
29, 35], but no atomic coordinates are publicly available. The molecule is of interest with respect to its toxicity. In the crystal, intramolecular O—H⋯O hydrogen bonds stabilize the molecular conformation, while intermolecular O—H⋯O hydrogen bonds link the molecules to form infinite chains along the [110] and [1-10] directions. The absolute configuration has been assigned by reference to an unchanging chiral centre in the synthetic procedure
Less efficient skin penetration of the metal allergen Pd2+ compared to Ni2+ and Co2+ from patch test preparations
Background
Contrary to Ni2+- and Co2+-induced allergic contact dermatitis (ACD), reactions against Pd2+ are rare. However, Pd2+ activates a larger T cell fraction in vitro, suggesting an inefficient skin penetration.
Objectives
This study compares Ni2+, Co2+ and Pd2+ skin penetration from commonly used diagnostic patch test preparations (PTPs) and aqueous metal salt solutions.
Methods
Using Franz diffusion cell assays, we applied the metals in PTPs (5% NiSO4, 1% CoCl2, 2% PdCl2 and 3% Na2PdCl4) and in solution to pigskin for 48 h, thereby mirroring the time frame of a patch test. The different compartments were analysed individually by inductively coupled plasma mass spectrometry.
Results
Metal ions were mainly retained in the upper stratum corneum layers. After application of PTPs, concentrations in the viable skin were lower for Pd2+ (1 and 7 μM) compared to Ni2+ and Co2+ (54 and 17 μM).
Conclusions
Ni2+ and Co2+ penetrated the skin more efficiently than Pd2+ and thus may sensitize and elicit ACD more easily. This was observed for ions applied in petrolatum and aqueous solutions. We hypothesize that the differently charged metal complexes are responsible for the varying skin penetration behaviours
Li dynamics in carbon-rich polymer-derived SiCN ceramics probed by nuclear magnetic resonance
We report Li, Si, and C NMR studies of two different
carbon-rich SiCN ceramics SiCN-1 and SiCN-3 derived from the preceramic
polymers polyphenylvinylsilylcarbodiimide and polyphenylvinylsilazane,
respectively. From the spectral analysis of the three nuclei at room
temperature, we find that only the C spectrum is strongly influenced by
Li insertion/extraction, suggesting that carbon phases are the major
electrochemically active sites for Li storage. Temperature and Larmor frequency
() dependences of the Li linewidth and spin-lattice relaxation
rates are described by an activated law with the activation energy
of 0.31 eV and the correlation time in the high temperature
limit of 1.3 ps. The power law dependence of on
which deviates from the standard Bloembergen, Purcell, and Pound (BPP) model
implies that the Li motion on the s timescale is governed by continuum
diffusion mechanism rather than jump diffusion. On the other hand, the rotating
frame relaxation rate results suggest that the slow motion of
Li on the ms timescale may be affected by complex diffusion and/or
non-diffusion processes.Comment: 28 pages with double line spacing, 7 figures and 2 tables, accepted
version in Journal of Power Source
The stigma of suicide survivorship and related consequences: a systematic review
Background: Cconsiderable proportion of the population experiences major life disruptions after losing a loved one to suicide. Social stigma attached to suicide survivors adds to complications occurring in the course of suicide bereavement. Despite its known risks, stigma related to suicide survivors has been sparsely investigated. Methods: We conducted a systematic literature search in PubMed, Web of Science, PsycInfo and PsyArticles, of studies indexed up through August 2015. Articles were eligible for inclusion if they addressed experiences of stigma in suicide survivors, compared them to other bereavement populations, or investigated stigmatizing attitudes within the public. The
search was restricted to English-language studies. Results: 25 records matched inclusion criteria. Study designs were heterogeneous, making comparisons difficult. Results demonstrated that suicide survivors experience stigma in the form of shame, blame, and avoidance. Suicide survivors showed higher levels of stigma than natural death survivors. Stigma was linked to concealment of the death, social withdrawal, reduced psychological and somatic functioning, and grief difficulties. Only one study investigated stigmatizing attitudes towards suicide survivors among the general population. Limitations: Internal and external validity of the studies was restricted by a lack of valid measures and selection bias. Conclusions: More methodologically sound research is needed to understand the impact of stigma on
suicide survivors\'' grief trajectories and to separate it from other grief aspects. Clinicians and grief-counselors as well as the public should be educated about the persistent stigma experienced by suicide survivors
An Amorphous Teflate Doped Aluminium Chlorofluoride: A Solid Lewis‐Superacid for the Dehydrofluorination of Fluoroalkanes
An anion-doped aluminium chlorofluoride AlCl0.1F2.8(OTeF5)0.1 (ACF-teflate) was synthesized. The material contains pentafluoroorthotellurate (teflate) groups, which mimic fluoride ions electronically, but are sterically more demanding. They are embedded into the amorphous structure. The latter was studied by PDF analysis, EXAFS data and MAS NMR spectroscopy. The mesoporous powder is a Lewis superacid, and ATR-IR spectra of adsorbed CD3CN reveal a blue-shift of the adsorption band by 73 cm−1, which is larger than the shift for SbF5. Remarkably, ACF-teflate catalyzes dehydrofluorination reactions of monofluoroalkanes to yield olefins in C6D6. In these cases, no Friedel-Crafts products were formed.German Research Foundation
http://dx.doi.org/10.13039/501100001659Diamond Light Source
http://dx.doi.org/10.13039/100011889German Research Foundation
http://dx.doi.org/10.13039/501100001659Peer Reviewe
An Amorphous Teflate Doped Aluminium Chlorofluoride: A Solid Lewis‐Superacid for the Dehydrofluorination of Fluoroalkanes
An anion‐doped aluminium chlorofluoride AlCl0.1F2.8(OTeF5)0.1 (ACF‐teflate) was synthesized. The material contains pentafluoroorthotellurate (teflate) groups, which mimic fluoride ions electronically, but are sterically more demanding. They are embedded into the amorphous structure. The latter was studied by PDF analysis, EXAFS data and MAS NMR spectroscopy. The mesoporous powder is a Lewis superacid, and ATR‐IR spectra of adsorbed CD3CN reveal a blue‐shift of the adsorption band by 73 cm−1, which is larger than the shift for SbF5. Remarkably, ACF‐teflate catalyzes dehydrofluorination reactions of monofluoroalkanes to yield olefins in C6D6. In these cases, no Friedel‐Crafts products were formed
Frequencies and TCR Repertoires of Human 2,4,6-Trinitrobenzenesulfonic Acid-specific T Cells
Allergic contact dermatitis is a widespread T cell-mediated inflammatory skin disease, but in vitro monitoring of chemical-specific T cells remains challenging. We here introduce short-term CD154/CD137 upregulation to monitor human T cell responses to the experimental sensitizer 2,4,6-trinitrobenzenesulfonic acid (TNBS). Peripheral blood mononuclear cells (PBMC) from healthy donor buffy coats were TNBS-modified and incubated with unmodified PBMC. After 5 and 16 h, we detected TNBS-specific activated CD154+CD4+ and CD137+CD8+ T cells by multi-parameter flow cytometry, respectively. Activated cells were sorted for restimulation and bulk T cell receptor (TCR) high-throughput sequencing (HTS). Stimulation with TNBS-modified cells (3 mM) induced CD154 expression on 0.04% of CD4+ and CD137 expression on 0.60% of CD8+ memory T cells, respectively (means, n = 11–17 donors). CD69 co-expression argued for TCR-mediated activation, which was further supported by TNBS-specific restimulation of 10/13 CD154+CD4+ and 11/15 CD137+CD8+ T cell clones and lines. Major histocompatibility complex (MHC) blocking antibodies prevented activation, illustrating MHC restriction. The high frequencies of TNBS-specific T cells were associated with distinct common changes in the TCR β-chain repertoire. We observed an overrepresentation of tryptophan and lysine in the complementarity determining regions 3 (CDR3) (n = 3–5 donors), indicating a preferential interaction of these amino acids with the TNBS-induced epitopes. In summary, the detection of TNBS-specific T cells by CD154/CD137 upregulation is a fast, comprehensive and quantitative method. Combined with TCR HTS, the mechanisms of chemical allergen recognition that underlie unusually frequent T cell activation can be assessed. In the future, this approach may be adapted to detect T cells activated by additional chemical sensitizers
Health Care Services Utilization and Health-Related Quality of Life of Syrian Refugees with Post-Traumatic Stress Symptoms in Germany (the Sanadak Trial)
Refugees who have fled from the ongoing civil war in Syria that arrived in Germany often develop post-traumatic stress symptoms (PTSS). The aim of this study was to determine health care services utilization (HCSU), health care costs and health-related quality of life (HrQoL) of Syrian refugees with mild to moderate PTSS without current treatment in Germany. The study was based on the baseline sample of a randomized controlled trial of a self-help app for Syrian refugees with PTSS (n = 133). HCSU and HrQoL based on the EQ-5D-5L and its visual analogue scale (EQ-VAS) were assessed with standardized interviews. Annual health care costs were calculated using extrapolated four-month HCSU and standardized unit costs. Associations between health care costs, HrQoL and PTSS severity were examined using generalized linear models. Overall, 85.0% of the sample utilized health care services within four months. The mean total annual health care costs were EUR 1920 per person. PTSS severity was not associated with health care costs. The EQ-5D-5L index score and the EQ-VAS score was 0.82 and 73.6, respectively. For Syrian refugees with higher PTSS severity, the EQ-5D-5L index score was lower (−0.17; p < 0.001). The HCSU and the resulting health care costs of Syrian refugees with mild to moderate PTSS without current treatment are low and those with a higher PTSS severity had a lower HrQoL
Recruitment and Baseline Characteristics of Participants in the “Sanadak” Trial: A Self-Help App for Syrian Refugees with Post-traumatic Stress
Many Syrian refugees residing in Germany have been exposed to traumatizing events, while treatment options are scarce. Therefore, the self-help app “Sanadak” was developed to target post-traumatic stress in Syrian refugees. We aimed to inspect the recruitment and baseline characteristics of the participants in the trial, which is conducted to evaluate the app. Analyses were based on the recruitment sample (n = 170) and the trial sample (n = 133). Data were collected during structured face-to-face interviews in the Arabic language. Targeted outcomes included post-traumatic stress (primary; Post-traumatic Diagnostic Scale for DSM-5/PDS-5) and depressive symptoms, anxiety, resilience, among others (secondary). Recruited individuals were M = 32.8 (SD = 11.2, range = 18–65) years old; 38.8% were women. The average PDS-5 score was 23.6 (SD = 13.2) regarding trauma exposure, which was most frequently related to experiencing military- or combat-related events (32.9%). Moreover, 46.5% had major depression and 51.8% showed low resilience. Anxiety was present in 40.6% of the trial participants. Psychological distress was high in Syrian refugees residing in Germany, enrolled in a trial targeting post-traumatic stress. This underlines the need for intervention. Our results provide important figures on the mental health of a not well-studied population group in Germany
Wicked facets of the German energy transition – examples from the electricity, heating, transport, and industry sectors
We shed light on wicked problems in the German energy transition. Our methods consist of a multiple-case study and multi-criteria analysis, utilising the wicked problems theoretical framework introduced by Horst Rittel and Melvin Webber [1973. “Dilemmas in a General Theory of Planning.” Policy Sciences 4 (2): 155–169. Accessed August 20, 2019. https://doi.org/10.1007/BF01405730]. Results from the energy supply, heating/cooling, transport, and industry sectors illustrate where and how the 10-point frame of wicked problems manifests in the German energy transition. The four cases exhibit more wicked tendencies in the governance domain than the technical domain and differ in their degrees of technology maturity, policy regulation, and knowledge states. We do not find that the German energy transition is inherently wicked. However, wickedness unfolds through the social setting into which technical solutions of the energy transition are embedded. We aim to highlight these intricacies and encourage scrutinising these wicked facets early on
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