Hydride-dehydride fine zirconium powders for pyrotechnics

In this paper, the possibility of obtaining fine zirconium powders by the hydrogenationdehydrogenation method is studied. The main parameters of the technological process that allow obtaining fine zirconium powders for pyrotechnics are determined. Hydrogenation and dehydrogenation of the samples are carried out in a rotating quartz tube placed in a furnace at temperatures of 380◦C and 850◦C, respectively. Zirconium hydride is milled using tungsten carbide balls to eliminate the presence of impurities. Thus it is possible to obtain a fine zirconium powder with a number-average particle size of 4.527 +- 2.650 Um and a specific surface area of 0.231 m2/g from the initial electrolytic zirconium powder with a number-average particle size of 220 Um and a specific surface area < 0.1 m2/g. The allowed relative error of measuring the specific surface area is +- 5%. Hence it is possible to reduce the particle size of zirconium powder by 54.6 times without changing the composition

Mental Health Impact of Early Stages of the COVID-19 Pandemic on Individuals with Pre-Existing Mental Disorders: A Systematic Review of Longitudinal Research

In view of disease-related threats, containment measures, and disrupted healthcare, individuals with pre-existing mental illness might be vulnerable to adverse effects of the COVID-19 pandemic. Previous reviews indicated increased mental distress, with limited information on peri-pandemic changes. In this systematic review, we aimed to identify longitudinal research investigating pre- to peri-pandemic and/or peri-pandemic changes of mental health in patients, focusing on the early phase and considering specific diagnoses. PsycINFO, Web of Science, the WHO Global literature on coronavirus disease database, and the Cochrane COVID-19 Study Register weresearched through 31 May 2021. Studies were synthesized using vote counting based on effect direction. We included 40 studies mostly from Western, high-income countries. Findings were heterogeneous, with improving and deteriorating mental health observed compared to pre-pandemic data, partly depending on underlying diagnoses. For peri-pandemic changes, evidence was limited, with some suggestion of recovery of mental distress. Study quality was heterogeneous; only few studies investigated potential moderators (e.g., chronicity of mental illness). Mental health effects on people with pre-existing conditions are heterogeneous within and across diagnoses for pre- to peri-pandemic and peri-pandemic comparisons. To improve mental health services amid future global crises, forthcoming research should understand medium- and long-term effects, controlling for containment measures

Interventions to foster mental health, psychosocial support, resilience and/or stress management in healthcare workers in face of the COVID-19 pandemic – protocol for a living systematic review

Regularly updated (every two months) living synthesis to identify and summarize the available literature on interventions to foster mental health, psychosocial support, resilience and/or stress management in healthcare workers in the face of the current pandemic. A detailed review protocol is presented in the "Living systematic review protocol" attached here. This work is part of the CEOsys project (https://www.covid-evidenz.de; https://www.ceosys.de) which is funded by the German Federal Ministry for Education and Research (BMBF) as part of the national network of academic medical research into COVID-19, Germany (Nationales Netzwerk Universitätsmedizin, NUM)

Consequences of the COVID-19 pandemic on the mental health and work ability of healthcare workers as well as risk and protective factors for mental health – protocol for a living systematic review

Regularly updated (every two months) living synthesis to identify and summarize the available literature on the impact of the SARS-CoV-2 pandemic on the mental health and work ability in healthcare workers as well as possible (demographic, psychosocial etc.) risk and protective factors for mental health. A detailed review protocol is presented in the "Living systematic review protocol" attached here. This work is part of the CEOsys project (https://www.covid-evidenz.de; https://www.ceosys.de) which is funded by the German Federal Ministry for Education and Research (BMBF) as part of the national network of academic medical research into COVID-19, Germany (Nationales Netzwerk Universitätsmedizin, NUM)

A Nationwide Cross-Sectional Online Survey on the Treatment of COVID-19-ARDS: High Variance in Standard of Care in German ICUs

Introduction: Coronavirus disease (COVID-19) has recently dominated scientific literature. Incomplete understanding and a lack of data concerning the pathophysiology, epidemiology, and optimal treatment of the disease has resulted in conflicting recommendations. Adherence to existing guidelines and actual treatment strategies have thus far not been studied systematically. We hypothesized that capturing the variance in care would lead to the discovery of aspects that need further research and—in case of proven benefits of interventions not being performed—better communication to care providers. Methods: This article is based on a quantitative and qualitative cross-sectional mixed-methods online survey among intensive-care physicians in Germany during the COVID-19 pandemic by the CEOsys (COVID-19 Evidence Ecosystem) network, endorsed by the German Interdisciplinary Association for Intensive Care and Emergency Medicine (DIVI) conducted from December 3 to 31 December 2020. Results: We identified several areas of care with an especially high variance in treatment among hospitals in Germany. Crucially, 51.5% of the participating ICUs (n = 205) reported using intubation as a last resort for respiratory failure in COVID-19 patients, while 21.8% used intubation early after admission. Furthermore, 11.5% considered extracorporeal membrane oxygenation (ECMO) in awake patients. Finally, 72.3% of respondents used the ARDS-network-table to titrate positive end-expiratory-pressure (PEEP) levels, with 36.9% choosing the low-PEEP table and 41.8% the high-PEEP table. Conclusions: We found that significant differences exist between reported treatment strategies and that adherence to published guidelines is variable. We describe necessary steps for future research based on our results highlighting significant clinical variability in care

Development and external validation of a clinical prediction model for functional impairment after intracranial tumor surgery

OBJECTIVE Decision-making for intracranial tumor surgery requires balancing the oncological benefit against the risk for resection-related impairment. Risk estimates are commonly based on subjective experience and generalized numbers from the literature, but even experienced surgeons overestimate functional outcome after surgery. Today, there is no reliable and objective way to preoperatively predict an individual patient's risk of experiencing any functional impairment. METHODS The authors developed a prediction model for functional impairment at 3 to 6 months after microsurgical resection, defined as a decrease in Karnofsky Performance Status of ≥ 10 points. Two prospective registries in Switzerland and Italy were used for development. External validation was performed in 7 cohorts from Sweden, Norway, Germany, Austria, and the Netherlands. Age, sex, prior surgery, tumor histology and maximum diameter, expected major brain vessel or cranial nerve manipulation, resection in eloquent areas and the posterior fossa, and surgical approach were recorded. Discrimination and calibration metrics were evaluated. RESULTS In the development (2437 patients, 48.2% male; mean age ± SD: 55 ± 15 years) and external validation (2427 patients, 42.4% male; mean age ± SD: 58 ± 13 years) cohorts, functional impairment rates were 21.5% and 28.5%, respectively. In the development cohort, area under the curve (AUC) values of 0.72 (95% CI 0.69-0.74) were observed. In the pooled external validation cohort, the AUC was 0.72 (95% CI 0.69-0.74), confirming generalizability. Calibration plots indicated fair calibration in both cohorts. The tool has been incorporated into a web-based application available at https://neurosurgery.shinyapps.io/impairment/. CONCLUSIONS Functional impairment after intracranial tumor surgery remains extraordinarily difficult to predict, although machine learning can help quantify risk. This externally validated prediction tool can serve as the basis for case-by-case discussions and risk-to-benefit estimation of surgical treatment in the individual patient