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The highest quality hexagonal boron nitride (hBN) crystals are grown from molten solutions. For hBN crystal growth at atmospheric pressure, typically the solvent is a combination of two metals, one with a high boron solubility and the other to promote nitrogen solubility. In this study, we demonstrate that high-quality hBN crystals can be grown at atmospheric pressure using pure iron as a flux. The ability to produce excellent-quality hBN crystals using pure iron as a solvent is unexpected, given its low solubility for nitrogen. The properties of crystals produced with this flux matched the best values ever reported for hBN a narrow Raman E2g vibration peak (7.6 cm-1) and strong phonon-assisted peaks in the photoluminescence spectra. To further test their quality, the hBN crytals were used as a substrate for WSe2 epitaxy. WSe2 was deposited with a low nucleation density, indicating the low defect density of the hBN. Lastly, the carrier tunneling through our hBN thin layers (3.5 nm) follows the Fowler-Nordheim model, with a barrier height of 3.7 eV, demonstrating hBN’s superior electrical insulating properties. This ability to produce high-quality hBN crystals in such a simple, environmentally friendly and economical process will advance two-dimensional material research by enabling integrated devices.In this study, the excellent hydrogen barrier properties of the atomic-layer-deposition-grown Al2O3 (ALD Al2O3) are first reported for improving the stability of amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs). Chemical species in Al2O3 were artificially modulated during the ALD process using different oxidants, such as H2O and O3 (H2O-Al2O3 and O3-Al2O3, respectively). When hydrogen was incorporated into the H2O-Al2O3-passivated TFT, a large negative shift in Vth (ca. -12 V) was observed. In contrast, when hydrogen was incorporated into the O3-Al2O3-passivated TFT, there was a negligible shift in Vth (ca. -0.66 V), which indicates that the O3-Al2O3 has a remarkable hydrogen barrier property. We presented a mechanism for trapping hydrogen in a O3-Al2O3 via various chemical and electrical analyses and revealed that hydrogen molecules were trapped by C-O bonds in the O3-Al2O3, preventing the inflow of hydrogen to the a-IGZO. Additionally, to minimize the deterioration of the pristine device that occurs after a barrier deposition, a bi-layered hydrogen barrier by stacking H2O- and O3-Al2O3 is adopted. Such a barrier can provide ultrastable performance without degradation. Therefore, we envisioned that the excellent hydrogen barrier suggested in this paper can provide the possibility of improving the stability of devices in various fields by effectively blocking hydrogen inflows.Many elderly individuals suffer from Alzheimer’s disease (AD), which causes a growing concern. We investigated the mechanism underlying the effects of vitamin D (VD) as a prophylactic treatment. A mouse model of okadaic-acid-induced AD-like pathology was used in vivo and in vitro. Morris water maze and field trials were used to assess cognitive function. The expression levels of VDR, MTHFR, LCMT-1, PP2A, p-TAU (Thr396), and T-TAU and the methylation level of PP2A were measured by Western blotting, and a reversal of the increase in the levels of these proteins in an AD cell model was observed. We used MTHFR-knockdown SH-SY5Y cells to further test the effects of VD, treated these cells with cycloheximide and MG132, and used RT-PCR to explore the mechanism underlying MTHFR targeting. We found that the effects of VD on AD were impaired by MTHFR knockdown through a pretranscriptional mechanism. In addition, VD attenuated AD-induced cognitive impairment and significantly suppressed the expression of TAU. Our findings indicated that VD treatment alleviated TAU accumulation and rescued methylated PP2A by increasing the expression of LCMT-1 and MTHFR.

Persistent somatic symptoms, such as pain and fatigue, have been referred to as somatization. Somatization is commonly associated with histories of trauma and posttraumatic stress disorder (PTSD). Although previous research has demonstrated that PTSD can predict somatic problems, there has been no examination of this at the level of PTSD symptom clusters and multidimensional assessment of somatic symptoms. this website We examined the association between the three International Classification of Disease (11th Edition) PTSD symptom clusters (reexperiencing in the here and now, avoidance, and sense of threat), measured in relation to the COVID-19 pandemic as the stressor, and somatic symptoms while statistically adjusting for confounding variables.

Participants were a nationally representative sample of 1041 adults from the general population of the Republic of Ireland. Physical health problems across the domains of pain, gastrointestinal, cardiopulmonary, and fatigue were assessed by the Patient Health Questionnaire, and PTSD symptoms were assessed using the International Trauma Questionnaire.

Sense of threat was associated with the presence of pain (β = 0.254), fatigue (β = 0.332), gastrointestinal (β = 0.234), and cardiovascular symptoms (β = 0.239). Avoidance was associated with pain (β = 0.347). Reexperiencing was not associated with any physical health variable.

In the context of COVID-19, the sense of threat symptoms in PTSD is most strongly related to somatic problems. Findings suggest that interventions addressing sense of threat symptoms might provide relief from somatization.

In the context of COVID-19, the sense of threat symptoms in PTSD is most strongly related to somatic problems. Findings suggest that interventions addressing sense of threat symptoms might provide relief from somatization.

This study aimed to quantify the prevalence of the adverse mental health outcomes in medical staff working in the hospital settings during the coronavirus disease 2019 (COVID-19) pandemic and explore the relative distribution of anxiety and depressive symptoms.

PubMed, EMBASE, China National Knowledge Infrastructure, WANFANG DATA, and VIP Database for Chinese Technical Periodicals were searched for articles published from January 1, 2019, to April 19, 2020. The prevalence estimates of adverse mental health symptoms in medical staff were pooled using the random-effects model.

A total of 35 articles and data of 25,343 medical staff were used in the final analysis. The pooled prevalence estimates in medical staff during the COVID-19 pandemic were as follows (ordered from high to low) fear-related symptoms, 67% (95% confidence interval [CI] = 61%-73%); high levels of perceived stress, 56% (95% CI = 32%-79%), anxiety symptoms, 41% (95% CI = 35%-47%); insomnia, 41% (95% CI = 33%-50%); posttraumatic stress disorder symptoms, 38% (95% CI = 34%-43%); depressive symptoms, 27% (95% CI = 20%-34%); and somatic symptoms, 16% (95% CI = 3%-36%).