The synthesis of highly efficient heterogeneous catalysts with uniformly dispersed noble metal particles and a suitable size is crucial for various industrial applications. However, the high cost and ...rarity of noble metals limit their economic efficiency, making it essential to improve the catalytic performance with lower noble metal loading. Herein, a two-step method was developed for the synthesis of uniformly dispersed ~3 nm Pt nanoparticles (NPs), strongly anchored on Ni(OH)2 nanosheets (NSs), which was proven by adequate structural characterizations. XPS analysis demonstrated that Ni(OH)2 NSs with abundant oxygen vacancies provided sufficient anchor sites for Pt NPs and prevented their agglomeration. The catalytic performance of Ptn/Ni(OH)2 (n (represents the addition amount of Pt precursors during the synthesis, μmol) = 5, 10, 15, and 20) NSs with controllable Pt loading were evaluated via the reduction of 4-nitrophenol to 4-aminophenol as a model reaction. The Pt10/Ni(OH)2 NSs exhibited the best activity and stability, with a reaction rate constant of 0.02358 s−1 and negligible deterioration in ten reaction cycles. This novel synthetic method shows potentials for the synthesis of highly efficient noble-metal-supported catalysts for heterogeneous catalysis.
Higher manganese silicides (HMS) powders were successfully prepared by a gas atomization technique. The gas atomized (GAed) powders showed spherical morphologies and a wide particle size ...distribution. No MnSi and Si phases were detected by XRD analyses, indicating that the high cooling rate during rapid solidification is effective in inhibiting the formation of second phases. When the GAed powders were consolidated by spark plasma sintering (SPS), the densified samples revealed almost the same phase composition as the powders and an isotropic feature. The contrast differences between different grains in backscattered electron images are believed to be associated with orientation differences. The HMS samples SPSed at different temperatures exhibited similar values of the Seebeck coefficient, but larger electrical conductivity and power factor were obtained in the sample SPSed at 1000 °C. Moreover, the HMS samples showed higher fracture toughness compared to those fabricated by a solid-state reaction and SPS process.
•Higher manganese silicides powders were successfully prepared by gas atomization.•The rapid cooling during gas atomization inhibited the formation of MnSi.•No second phases were found from the XRD patterns of powders and sintered samples.•The sintered samples showed larger electrical conductivity and powder factor.
ObjectivesTo assess the magnitude of mental health outcomes and associated factors among psychiatric professionals in mental health services during COVID-19 in China.Design, setting and ...participantsThis cross-sectional, survey-based, region-stratified study collected demographic data and mental health measurements from psychiatric professionals in 34 hospitals between 29 January and 7 February 2020, in China. Hospitals equipped with fever clinics or deployed on wards for patients with COVID-19 were eligible.Primary outcome and measuresThe severity of symptoms of depression, anxiety, insomnia and distress were assessed by the Chinese versions of 9-item Patient Health Questionnaire, 7-item Generalised Anxiety Disorder, 7-item Insomnia Severity Index and 22-item Impact of Event Scale-Revised, respectively. Multivariable logistic regression and structural equation modelling was performed to identify factors associated with mental health outcomes.ResultsA total of 610 psychiatric professionals were included. 29.8% were employed in Wuhan, and 22.5% were frontline workers. A considerable proportion of participants reported symptoms of depression (461 (75.6%)), anxiety (282 (46.2%)), insomnia (336 (55.1%)) and mental stress (481 (78.9%)). Psychiatric symptoms were associated with worrying about infection (eg, OR 2.36 (95% CI 1.27 to 4.39) for anxiety), risks of exposure to COVID-19 (eg, having inadequate personal protection equipment, OR 2.43 (1.32 to 4.47) for depression) and self-perceived physical health (eg, OR 3.22 (2.24 to 4.64) for mental stress). Information sources of COVID-19 were also found to be both positively (eg, information from relatives, OR 2.16 (1.46 to 3.21) for mental stress) and negatively (eg, information from TV, OR 0.52 (0.35 to 0.77) for mental stress) associated with mental stress. There is preliminary evidence that mental health might benefit from greater availability of mental healthcare services. The structural equation model analysis indicated that worrying about infection may be the primary mediator via which risk of exposure to COVID-19 pandemic affects the mental health of psychiatric professionals.ConclusionsThe current findings demonstrate several pathways via which the COVID-19 pandemic may have negatively affected the mental health of psychiatric professionals in China.
Al2O3 matrix composites containing in-situ formed monoclinic zirconia (m-ZrO2) and BaO·7.3Al2O3 (one of Ba-β-Al2O3 compounds) were prepared via reactive sintering of Al2O3 and BaZrO3 powders. When ...yttria-stabilized zirconia (YSZ) with Y2O3 contents of 1.5 mol% (1.5YSZ), 2 mol% (2YSZ), and 3 mol% (3YSZ) as well as Y2O3 particles were introduced into Al2O3 and BaZrO3 powder mixtures, the in-situ formed m-ZrO2 was stabilized, resulting from the migration of Y3+ from YSZ or Y2O3 to m-ZrO2 during sintering. The incorporation of YSZ contributed to the refinement of Al2O3 grains, whereas Y2O3-added samples showed larger grain sizes of Al2O3 matrix. The samples with YSZ or Y2O3 addition exhibited high fracture toughness, which is attributed to crack deflection/bridging and transformation toughening of ZrO2. Although the phase transformation is mainly derived from ZrO2 formed during sintering, 1.5YSZ particles added in the composites still showed much higher phase transformability compared to 2YSZ and 3YSZ particles.
To improve the mechanical properties and thermal shock resistance of zirconia toughened alumina (ZTA) composites, barium carbonate (BaCO3) was added to yttria-stabilized zirconia (YSZ) and Al2O3 ...powders to form ZTA/Ba-β-Al2O3 composites, which were prepared by a solid-state reactive sintering method. As BaCO3 content increased, more Ba-β-Al2O3 was formed, resulting in the decreases in relative density and Vickers hardness. The fracture toughness was enhanced with increasing BaCO3 content and reached a peak at 4 wt% BaCO3. The improved fracture toughness is the result of synergistic toughening effects of martensitic transformation of ZrO2 and crack deflection/bridging. After thermal shock tests, the residual strength of ZTA/Ba-β-Al2O3 composites was higher than that of ZTA. The improvement in thermal shock resistance is mainly ascribed to the formation of elongated Ba-β-Al2O3 with a hexagonal structure, which can dissipate the energy associated with crack propagation during thermal shock.
Intratumoral hepatitis B virus (HBV) integrations and mutations are related to hepatocellular carcinoma (HCC) progression. Circulating cell-free DNA (cfDNA) has shown itself as a powerful noninvasive ...biomarker for cancer. However, the HBV integration and mutation landscape on cfDNA remains unclear.
A cSMART (Circulating Single-Molecule Amplification and Resequencing Technology)-based method (SIM) was developed to simultaneously investigate HBV integration and mutation landscapes on cfDNA with HBV-specific primers covering the whole HBV genome. Patients with HCC (
= 481) and liver cirrhosis (LC;
= 517) were recruited in the study.
A total of 6,861 integration breakpoints including
and
were discovered in HCC cfDNA, more than in LC. The concentration of circulating tumor DNA (ctDNA) was positively correlated with the detection rate of these integration hotspots and total HBV integration events in cfDNA. To track the origin of HBV integrations in cfDNA, whole-genome sequencing (WGS) was performed on their paired tumor tissues. The paired comparison of WGS data from tumor tissues and SIM data from cfDNA confirmed most recurrent integration events in cfDNA originated from tumor tissue. The mutational landscape across the whole HBV genome was first generated for both HBV genotype C and B. A region from nt1100 to nt1500 containing multiple HCC risk mutation sites (OR > 1) was identified as a potential HCC-related mutational hot zone.
Our study provides an in-depth delineation of HBV integration/mutation landscapes at cfDNA level and did a comparative analysis with their paired tissues. These findings shed light on the possibilities of noninvasive detection of virus insertion/mutation.
To explore the causes of sudden unexpected death (SUD) and to search for high-risk people, whole exome sequencing (WES) was performed in families with SUDs. METHODS: Whole exome sequencing of 25 ...people from 14 SUD families were screened based on cardiac disease-associated gene variants, and their echocardiograms and electrocardiograms (ECG) were also examined. The protein function of mutated genes was predicted by SIFT, PolyPhen2 and Mutation Assessor.
In the group of 25 people from 14 SUD families, 49 single nucleotide variants (SNVs) of cardiac disease-associated genes were found and verified by Sanger sequencing. 29 SNVs of 14 cardiac disorder-related genes were predicted as pathogens by software. Among them, 7 SNVs carried by two or more members were found in 5 families, including SCN5A (c.3577C > T), IRX4 (c.230A > G), LDB3 (c.2104 T > G), MYH6 (c.3G > A), MYH6 (c.3928 T > C), TTN (c.80987C > T) and TTN (c.8069C > T). 25 ECGs were collected. In summary, 4 people had J-point elevation, 2 people had long QT syndrome (LQTS), 4 people had prolonged QT interval, 3 people had T-wave changes, 3 people had sinus tachycardia, 4 people had sinus bradycardia, 4 people had left side of QRS electrical axis, and 3 people had P wave broadening. Echocardiographic results showed that 1 person had atrial septal defect, 1 person had tricuspid regurgitation, and 2 people had left ventricular diastolic dysfunction.
Of the 14 heart disease-associated genes in 14 SUDs families, there are 7 possible pathological SNVS may be associated with SUDs. Our results indicate that people with ECG abnormalities, such as prolonged QT interval, ST segment changes, T-wave change and carrying the above 7 SNVs, should be the focus of prevention of sudden death.
Respective changes in functional and anatomical connectivities of default mode network (DMN) after antipsychotic treatment have been reported. However, alterations in structure-function coupling ...after treatment remain unknown. We performed diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging in 42 drug-naive first-episode schizophrenia patients (FESP) both at baseline and after 8-weeks risperidone monotherapy, and in 38 healthy volunteers. Independent component analysis was used to assess voxel-wise DMN synchrony. A 3-step procedure was used to trace fiber paths between DMN components. Structure-function couplings were assessed by Pearson's correlations between mean fractional anisotropy and temporal correlation coefficients in major tracts of DMN. Pretreatment, FESP showed impaired functional connectivity in posterior cingulate cortex/precuneus (PCC/PCUN) and medial prefrontal cortex (mPFC), but no abnormalities in fibers connecting DMN components. After treatment, there were significant increases in functional connectivities of PCC/PCUN. Increases in functional connectivity between PCC/PCUN and mPFC correlated with improvement in positive symptoms. The structure-function coupling in tracts connecting PCC/PCUN and bilateral medial temporal lobes decreased after treatment. No alterations in DMN fiber integrity were detected. This combination of functional and anatomical findings in FESP contributes novel evidence related to neurobehavioral treatment effects. Increased functional connectivities between PCC/PCUN and mPFC may be treatment response biomarkers for positive symptoms. Increases in functional connectivities, no alterations in fiber integrity, combined with decreases in structural-functional coupling, suggest that DMN connectivities may be dissociated by modality after 8-week treatment. Major limitations of this study, however, include lack of repeat scans in healthy volunteers and control group of patients taking placebo or comparator antipsychotics.
•Suicidal ideation is prevalent among hospital workers who exposed to COVID-19.•Traumatic event exposure increases the risk of suicidal ideation.•Nightmares fully mediate the relationship between ...trauma exposure and suicidal ideation.•Nightmares intervention might be considered as a component when developing suicide prevention strategies.
Trauma experience increases the risk of suicidal ideation, but little is known about potentially psychological mechanisms underlying this relationship. This study aims to examine the relationship between coronavirus disease 2019 (COVID-19)-related traumatic event (CTE) exposure and suicidal ideation among hospital workers, and identify mediating roles of sleep disturbances in this relationship.
Workers in seven designated hospitals in Wuhan, China, were invited to participate in an online survey from May 27, 2020, to July 31, 2020. Participants completed a self-report questionnaire to evaluate demographic characteristics, level of CTE exposures, nightmare frequency, insomnia severity, symptoms of depression and anxiety, and suicidal ideation. A series of correlation analyses were performed, and a mediation model was generated to examine correlations between CTE exposure, sleep disturbances, and suicidal ideation.
: A total of 16,220 hospital workers were included in the final analysis, 13.3% of them reported suicidal ideation in the past month. CTE exposure was significantly associated with insomnia severity, nightmare frequency, and suicidal ideation. After controlling potential confounders, nightmares but not insomnia, depression, or anxiety were shown to be independent risk factors for suicidal ideation. Pathway analyses showed that the relationship between CTE exposure and suicidal ideation was fully mediated by nightmares (proportion mediated 66.4%) after adjusting for demographic characteristics and psychological confounders.
Cross-sectional design precluded the investigation of causal relationships.
CTE exposure increases risk of hospital workers’ suicidal ideation that is mediated by nightmares, suggesting nightmares intervention might be considered as a component when developing suicide prevention strategies.
Objective
Iron plays a significant role in multiple biological processes. The purpose of this study was to measure whether iron mediated osteoclast differentiation through regulation of triggering ...receptor expressed in myeloid cells‐2 (Trem‐2) expression and the PI3K/Akt signaling pathway.
Methods
The effects of six different concentrations of ferric ammonium citrate (FAC) (100, 80, 40, 20, 10 and 0 μmol/L) on RAW 264.7 cells proliferation were assessed by Cell Counting Kit‐8 (CCK‐8) gassay. Tartrate resistant acid phosphatase (TRAP) assay was performed to detect the effects of FAC on osteoclast formation. The expression of osteoclast differentiation‐related (TRAP, NFATc‐1, and c‐Fos) and Trem‐2 mRNA and proteins was analyzed by reverse transcription‐polymerase chain reaction and western blot, respectively. Si‐Trem‐2 was constructed and transfected to RAW264.7 to measure the effects of Trem‐2 on FAC‐mediated osteoclast formation. TRAP assay and osteoclast differentiation‐related gene analyses were further performed to identify the role of Trem‐2 in osteoclastogenesis. The Search Tool for the Retrieval of Interacting Genes (STRING) was used to explore the target genes of Trem‐2. Trem‐2‐related gene ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were used for further in‐depth analysis. PI3K/Akt pathway‐related proteins were detected by immunofluorescence and western blot.
Results
In groups with FAC concentration of 10 (102.5 ± 3.1), 20 (100.5 ± 1.5), and 40 μmol/L (98.7 ± 3.1), compared with the control group (100.1 ± 2.2), cell viability was not significantly different from the control (P > 0.05). When the concentration of FAC exceeded 80 μmol/L, cell viability was significantly decreased (87.5 ± 2.8 vs 100.1 ± 2.2, P < 0.05). FAC promotes Trem‐2 expression and osteoclast differentiation in a dose‐response manner (P < 0.05). The number of osteoclast‐like cells was found to be reduced following transfection with the siRNA of Trem‐2 (42 ± 3 vs 30 ± 5, P < 0.05). We observed that most of Trem‐2 target genes are primarily involved in response to organic substance, regulation of reactive oxygen species metabolic process, and regulation of protein phosphorylation. The STRING database revealed that Trem‐2 directly target two gene nodes (Pik3ca and Pik3r1), which are key transcriptional cofactors of the PI3K/Akt signaling pathway. KEGG pathways include the “PI3K‐Akt signaling pathway,” the “thyroid hormone signaling pathway”, “prostate cancer,” the “longevity regulating pathway,” and “insulin resistance.” Expression of p‐PI3K and p‐Akt protein, measured by immunofluorescence and western blotting, was markedly increased in the FAC groups. Trem‐2 siRNA caused partial reduction of these two proteins (p‐PI3K and p‐Akt) compared to the FAC alone group.
Conclusion
The FAC promoted osteoclast differentiation through the Trem‐2‐mediated PI3K/Akt signaling pathway. However, its regulation osteoclastogenesis should be verified through further in vivo studies.
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