49 research outputs found
Insights into the mechanism of electrochemical ozone production via water splitting on the Ni and Sb Doped SnO2 catalyst
The H2O splitting mechanism is a very attractive alternative used in electrochemistry for the formation of O3. The most efficient catalysts employed for this reaction at room temperature are SnO2-based, in particular the Ni/Sb-SnO2 catalyst. In order to investigate the H2O splitting mechanism Density Functional Theory (DFT) was performed on a Ni/Sb-SnO2 surface with oxygen vacancies. By calculating different SnO2 facets, the (110) facet was deemed most stable, and further doped with Sb and Ni. On this surface, the H2O splitting mechanism was modelled paying particular attention to the final two steps, the formation of O2 and O3. Previous studies on β-PbO2 have shown that the final step in the reaction (the formation of O3) occurs via an Eley-Rideal style interaction where surface O2 desorbs before attacking surface O to form O3. It is revealed that for Ni/Sb-SnO2, although the overall reaction is the same the surface mechanism is different. The formation of O3 is found to occur through a Langmuir-Hinshelwood mechanism as opposed to Eley-Rideal. In addition to this the relevant adsorption energies (Eads), Gibb’s free energy (ΔGrxn) and activation barriers (Eact) for the final two steps modelled in the gas phase have been shown; providing the basis for a tool to develop new materials with higher current efficiencies
Natural-language-driven Simulation Benchmark and Copilot for Efficient Production of Object Interactions in Virtual Road Scenes
We advocate the idea of the natural-language-driven(NLD) simulation to
efficiently produce the object interactions between multiple objects in the
virtual road scenes, for teaching and testing the autonomous driving systems
that should take quick action to avoid collision with obstacles with
unpredictable motions. The NLD simulation allows the brief natural-language
description to control the object interactions, significantly reducing the
human efforts for creating a large amount of interaction data. To facilitate
the research of NLD simulation, we collect the Language-to-Interaction(L2I)
benchmark dataset with 120,000 natural-language descriptions of object
interactions in 6 common types of road topologies. Each description is
associated with the programming code, which the graphic render can use to
visually reconstruct the object interactions in the virtual scenes. As a
methodology contribution, we design SimCopilot to translate the interaction
descriptions to the renderable code. We use the L2I dataset to evaluate
SimCopilot's abilities to control the object motions, generate complex
interactions, and generalize interactions across road topologies. The L2I
dataset and the evaluation results motivate the relevant research of the NLD
simulation.Comment: 12 pages, 6 figure
Cortical hierarchy disorganization in major depressive disorder and its association with suicidality
ObjectivesTo explore the suicide risk-specific disruption of cortical hierarchy in major depressive disorder (MDD) patients with diverse suicide risks.MethodsNinety-two MDD patients with diverse suicide risks and 38 matched controls underwent resting-state functional MRI. Connectome gradient analysis and stepwise functional connectivity (SFC) analysis were used to characterize the suicide risk-specific alterations of cortical hierarchy in MDD patients.ResultsRelative to controls, patients with suicide attempts (SA) had a prominent compression from the sensorimotor system; patients with suicide ideations (SI) had a prominent compression from the higher-level systems; non-suicide patients had a compression from both the sensorimotor system and higher-level systems, although it was less prominent relative to SA and SI patients. SFC analysis further validated this depolarization phenomenon.ConclusionThis study revealed MDD patients had suicide risk-specific disruptions of cortical hierarchy, which advance our understanding of the neuromechanisms of suicidality in MDD patients
Identification of novel benzothiopyranone compounds against Mycobacterium tuberculosis through scaffold morphing from benzothiazinones
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Germline-Encoded TCR-MHC Contacts Promote TCR V Gene Bias in Umbilical Cord Blood T Cell Repertoire.
T cells recognize antigens as peptides bound to major histocompatibility complex (MHC) proteins through T cell receptors (TCRs) on their surface. To recognize a wide range of pathogens, each individual possesses a substantial number of TCRs with an extremely high degree of variability. It remains controversial whether germline-encoded TCR repertoire is shaped by MHC polymorphism and, if so, what is the preference between MHC genetic variants and TCR V gene compatibility. To investigate the "net" genetic association between MHC variations and TRBV genes, we applied quantitative trait locus (QTL) mapping to test the associations between MHC polymorphism and TCR β chain V (TRBV) genes usage using umbilical cord blood (UCB) samples of 201 Chinese newborns. We found TRBV gene and MHC loci that are predisposed to interact with one another differ from previous conclusions. The majority of MHC amino acid residues associated with the TRBV gene usage show spatial proximities in known structures of TCR-pMHC complexes. These results show for the first time that MHC variants bias TRBV gene usage in UCB of Chinese ancestry and indicate that germline-encoded contacts influence TCR-MHC interactions in intact T cell repertoires
Mediating effect of successful aging on the relationship between psychological resilience and death anxiety among middle-aged and older adults with hypertension
ObjectiveThe aging trend of China's population is severe and successful aging (SA) is imminent. Aging can lead to various chronic diseases, with hypertension being the most common. Due to this lifelong disease, patients suffer from many anxieties, as death anxiety (DA) can be the most prevalent. Studies have exhibited that middle-aged adults approaching the transition to an older state show more pronounced DA than the more senior. It has been suggested that psychological resilience (PR) can reduce DA. Therefore, this study aimed to analyze the mediating effect of SA between PR and DA in middle-aged and older adults with hypertension.MethodsA cross-sectional survey was designed. From August to December 2021, 298 middle-aged and older adults with hypertension were selected by multistage cluster random sampling in three districts (Ling he District, Gu ta District, and Tai He District) of Jinzhou City, Liaoning Province. They were surveyed using the demographic questionnaires, the Conner-Davidson Resilience Scale, the Successful Aging Inventory, and the Chinese version of a Likert-type Templer-Death Anxiety Scale. Descriptive analyses, independent sample T-test, and one-way analysis of variance (ANOVA) were used to describe demographic characteristics among hypertensive patients with different characteristics, respectively. Statistics were considered significant when P < 0.05. Pearson correlation coefficients describe the relationship between PR, SA, and DA. The research model was shaped through Structural Equation Modeling (SEM). SPSS PROCESS macro was used to verify the mediation model. A binary logistic regression model was used with DA as the dependent variable.ResultsThe scores for PR, SA, and DA in hypertensive patients are (49.52 ± 14.38) points, (51.22 ± 7.63) points, and (46.67 ± 9.03) points. PR was negatively correlated with DA (r = −0.307, P < 0.01). Moreover, incorporating SA as a mediating variable in PR and DA, SA was positively correlated with PR (r = 0.335, P < 0.01) and DA (r = 0.085, P > 0.05). The direct effect is opposite to the sign of the indirect effect. There is a suppression between PR and DA with a percentage of 20.7%. Good self-assessed health status [0.057 (0.018, 0.183)] may be a protective factor for DA.ConclusionHealthcare providers should improve the PR of middle-aged and older adults with hypertension through interventions that reduce DA and increase the likelihood of SA
Impact of alirocumab/evolocumab on lipoprotein (a) concentrations in patients with familial hypercholesterolaemia: a systematic review and meta-analysis of randomized controlled trials
Introduction: Familial hypercholesterolaemia (FH) is a common hereditary genetic disorder, characterized by elevated circulating low-density lipoprotein cholesterol (LDL-C) and lipoprotein (a) [Lp(a)] concentrations, leading to atherosclerotic cardiovascular disease (ASCVD). Two types of proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors — alirocumab and evolocumab — are efficient drugs in the treatment of FH, which can effectively reduce Lp(a) levels.
Material and methods: Embase, MEDLINE, and PubMed up to November 2022 were searched for randomized clinical trials (RCTs) evaluating the effect of alirocumab/evolocumab and placebo treatment on plasma Lp(a) levels in FH. Statistics were analysed by Review Manager (RevMan 5.3) and Stata 15.1.
Results: Eleven RCTs involved a total of 2408 participants. Alirocumab/evolocumab showed a significant efficacy in reducing Lp(a) [weighted mean difference (WMD): –20.10%, 95% confidence interval (CI): –25.59% to –14.61%] compared with placebo. In the drug type subgroup analyses, although the efficacy of evolocumab was slightly low (WMD: –19.98%, 95% CI: –25.23% to –14.73%), there was no difference with alirocumab (WMD: –20.54%, 95% CI: –30.07% to –11.02%). In the treatment duration subgroup analyses, the efficacy of the 12-week duration group (WMD: –17.61%, 95% CI: –23.84% to –11.38%) was lower than in the group of ≥ 24 weeks’ duration (WMD: –22.81%, 95% CI: –31.56% to –14.07%). In the participants’ characteristics subgroup analyses, the results showed that no differential effect of alirocumab/evolocumab therapy on plasma Lp(a) concentrations was observed (heterozygous FH [HeFH] WMD: –20.07%, 95% CI: –26.07% to –14.08%; homozygous FH [HoFH] WMD: –20.04%, 95% CI: –36.31% to –3.77%). Evaluation of all-cause adverse events (AEs) between alirocumab/evolocumab groups and placebo groups [relative risk (RR): 1.05, 95% CI: 0.98–1.12] implied no obvious difference between the 2 groups.
Conclusions: Anti-PCSK9 drugs (alirocumab and evolocumab) may be effective as therapy for reducing serum Lp(a) levels in FH, and no differences were observed in treatment durations, participant characteristics, and other aspects of the 2 types of PCSk9 inhibitors.
However, further experimental studies and RCTs are warranted to clarify the mechanism of PSCK9 inhibitors to lowering Lp(a) concentrations in FH