Adsorptions of metal adatoms on graphene-like BC3 and their rich electronic properties： A first-principles study

Density functional calculations have been performed to investigate the adsorption of twenty two different kinds of metal adatoms on graphene-like BC3. In contrast to the graphene adsorbed with adatoms, the BC3 with adatoms shows many interesting properties.（1） The interaction between the metal adatoms and the BC3 sheet is remarkably strong. The Li, Na, K, and Ca possess the binding energies larger than the cohesive energies of their corresponding bulk metals.（2）The Li, Na, and K adatoms form approximately ideal ionic bonds with BC3, while the Be, Mg, and Ca adatoms form ionic bonds with BC3 with slight hybridization of covalent bonds. The Al, Ga, In, Sn, and all transition metal adatoms form covalent bonds with BC3.（3） For all the structures studied, there exhibit metal, half-metal, semiconducting, and spin-semiconducting behaviors. Especially, the BC3 with Co adatom shows a quantum anomalous Hall（QAH） phase with a Chern number of -1 based on local density approximation calculations.（4） For Li, Na, K, Ca, Ga, In, Sn, Ti, V, Cr,Ni, Pd, and Pt, there exists a trend that the adatom species with lower ionization potential have lower work function. Our results indicate the potential applications of functionalization of BC3 with metal adatoms.

Machine learning modeling identifies hypertrophic cardiomyopathy subtypes with genetic signature

Previous studies have revealed that patients with hypertrophic cardiomyopathy(HCM)exhibit differences in symptom severity and prognosis,indicating potential HCM subtypes among these patients.Here,793 patients with HCM were recruited at an average follow-up of 32.78±27.58 months to identify potential HCM subtypes by performing consensus clustering on the basis of their echocardiography features.Furthermore,we proposed a systematic method for illustrating the relationship between the phenotype and genotype of each HCM subtype by using machine learning modeling and interactome network detection techniques based on whole-exome sequencing data.Another independent cohort that consisted of 414 patients with HCM was recruited to replicate the findings.Consequently,two subtypes characterized by different clinical outcomes were identified in HCM.Patients with subtype 2 presented asymmetric septal hypertrophy associated with a stable course,while those with subtype 1 displayed left ventricular systolic dysfunction and aggressive progression.Machine learning modeling based on personal whole-exome data identified 46 genes with mutation burden that could accurately predict subtype propensities.Furthermore,the patients in another cohort predicted as subtype 1 by the 46-gene model presented increased left ventricular end-diastolic diameter and reduced left ventricular ejection fraction.By employing echocardiography and genetic screening for the 46 genes,HCM can be classified into two subtypes with distinct clinical outcomes.

Millisecond synthesis of CoS nanopartides for highly efficient overall water splitting

High performance and low-cost electrocatalysts for overall water splitting,i.e.,catalyzing hydrogen and oxygen evolution reactions with the same material,are of great importance for large-scale,renewable energy conversion processes.Here,we report an ultrafast(~7 ms)synthesis tech nique for tran sition metal chalcoge nide n anoparticles assisted by high temperature treatme nt.As a proof of con cept,we dem on strate that cobalt sulfide(~20 nm in diameter)@few-layer graphe ne(~2 nm in thick ness)core-shell nan oparticles embedded in RGO nano sheets exhibit remarkable bifunctional electrocatalytic activity and stability for overall water splitting,which is comparable to commercial 40 wt.%platinum/carbon(Pt/C)electrocatalysts.After 60 h of continuous operation,10 mA crrT?water splitting current density can still be achieved at a low potential of^1.77 V without any activity decay,which is among the most active for non-noble material based electrocatalysts.The presented study provides prospects in synthesizing highly efficient bifunctional electrocatalysts for large-scale energy conversion application via a simple yet efficient technique.

前背侧终纹床核中与焦虑相关的细胞类型特异性神经环路图谱的研究

焦虑是生物个体面临外界环境潜在威胁时的本能反应.既往研究表明终纹床核(the bed nucleus of the stria terminalis, BNST)在调节焦虑过程中起着重要作用,但其中与焦虑行为相关的神经环路构筑和功能尚未可知.本研究在前背侧终纹床核(anterior-dorsal BNST, ad BNST)中发现两类独立分布的细胞群体,分别特异性表达促肾上腺皮质激素释放激素(corticotropin-releasing hormone, CRH)和蛋白激酶C-δ(protein kinase C-δ, PKC-δ)分子.利用神经环路示踪、全细胞膜片钳、在体神经元钙离子成像以及化学遗传学手段,本文阐明了ad BNST的CRH与PKC-δ阳性神经元的局部和长距离的神经环路连接特点及其对小鼠焦虑行为产生的不同调控作用.研究结果表明, CRH与PKC-δ神经元接收相似的上游脑区神经投射,并在部分下游脑区的投射密度中表现出显著性差异.该结果提示,二者可能参与到不同的焦虑行为调控中.进一步的功能研究结果发现,特异性地操纵CRH和PKC-δ阳性神经元能够分别产生致焦虑和抗焦虑作用.本研究揭示了ad BNST脑区CRH与PKC-δ神经元的功能异质性,为后续调控焦虑的神经环路机制的研究提供了坚实的基础.

Catalyst-Free In Situ Carbon Nanotube Growth in Confined Space via High Temperature Gradient

Carbonaceous materials,such as graphite,carbon nanotubes(CNTs),and graphene,are in high demand for a broad range of applications,including batteries,capacitors,and composite materials.Studies on the transformation between diferent types of carbon,especially from abundant and low-cost carbon to high-end carbon allotropes,have received surging interest.Here,we report that,without a catalyst or an external carbon source,biomass-derived amorphous carbon and defective reduced graphene oxide(RGO)can be quickly transformed into CNTs in highly confned spaces by high temperature Joule heating.Combined with experimental measurements and molecular dynamics simulations,we propose that Joule heating induces a high local temperature at defect sites due to the corresponding high local resistance.Te resultant temperature gradient in amorphous carbon or RGO drives the migration of carbon atoms and promotes the growth of CNTs without using a catalyst or external carbon source.Our fndings on the growth of CNTs in confned spaces by fast high temperature Joule heating shed light on the controlled transition between diferent carbon allotropes,which can be extended to the growth of other high aspect ratio nanomaterials.

Whole-exome sequencing reveals genetic risks of early-onset sporadic dilated cardiomyopathy in the Chinese Han population

To reveal genetic risks of early-onset sporadic dilated cardiomyopathy(DCM) patients in the Chinese Han population, we enlisted 363 DCM cases and 414 healthy controls. Whole-exome sequencing and phenotypic characterization were conducted. In total, we identified 26 loss-of-function(LOF) candidates and 66 pathogenic variants from 33 genes, most of which were novel.The deleterious variants can account for 25.07%(91/363) of all patients. Furthermore, rare missense variants in 21 genes were found to be significantly associated with DCM in burden tests. Other than rare variants, twelve common SNPs were significantly associated with an increased risk of DCM in allele-based genetic model association analysis. Of note, in the cumulative risk model, high-risk subjects had a 3.113-fold higher risk of developing DCM than low-risk subjects. Also, DCM in the high-risk group had a younger age of onset than that in the low-risk group. In terms of cardiac function, the mean left ventricular ejection fraction of patients with the deleterious variants was lower than those without(27.73%±10.02% vs. 30.61%±10.85%, P=0.026).To conclude, we mapped a comprehensive atlas of genetic risks in Chinese patients with DCM that might lead to new insights into the mechanisms and risk stratification for DCM.

Identification of COL3A1 variants associated with sporadic thoracic aortic dissection: a case-control study

Thoracic aortic dissection(TAD)without familial clustering or syndromic features is known as sporadic TAD(STAD).So far,the genetic basis of STAD remains unknown.Whole exome sequencing was performed in 223 STAD patients and 414 healthy controls from the Chinese Han population(N=637).After population structure and genetic relationship and ancestry analyses,we used the optimal sequence kernel association test to identify the candidate genes or variants of STAD.We found that COL3A1 was significantly relevant to STAD(P=7.35×10^(−6))after 10000 times permutation test(P=2.49×10^(−3)).Moreover,another independent cohort,including 423 cases and 734 non-STAD subjects(N=1157),replicated our results(P=0.021).Further bioinformatics analysis showed that COL3A1 was highly expressed in dissected aortic tissues,and its expression was related to the extracellular matrix(ECM)pathway.Our study identified a profile of known heritable TAD genes in the Chinese STAD population and found that COL3A1 could increase the risk of STAD through the ECM pathway.We wanted to expand the knowledge of the genetic basis and pathology of STAD,which may further help in providing better genetic counseling to the patients.