Synchronous organic-inorganic co-intercalated ammonium vanadate cathode for advanced aqueous zinc-ion batteries

Vanadium-based cathode materials are attractive for aqueous zinc-ion batteries(AZIBs)owing to the high capacity from their open frameworks and multiple valences.However,the cycle stability and rate capability are still restricted by the low electrical conductivity and trapped diffusion kinetics.Here,we propose an organic-inorganic co-intercalation strategy to regulate the structure of ammonium vanadate(NH_(4)V_(4)O_(10),NVO).The introduction of Al^(3+)and polyaniline(PANI)induces the optimized layered structure and generation of urchin-like hierarchical construction(AP-NVO),based on heterogeneous nucleation and dissolution-recrystallization growth mechanism.Owing to these favorable features,the AP-NVO electrode delivers a desirable discharge capacity of 386 mA h g^(-1) at 1.0 A g^(-1),high-rate capability of 263 mA h g^(-1 )at 5.0 A g^(-1) and excellent cycling stability with 80.4%capacity retention over 2000 cycles at 5.0 A g^(-1).Such satisfactory electrochemical performance is believed to result from the enhanced reaction kinetics provided by the stable layered structure and a high intercalation pseudo-capacitance reaction.These results could provide enlightening insights into the design of layered vanadium oxide cathodematerials.

TiO_(2)负载超低含量AuPd纳米颗粒在水蒸气条件下实现稳定的光催化甲烷偶联生成乙烷

选择性转化甲烷为C_(2)烃类是一种高效利用天然气并减少对传统化石燃料依赖的方法。与高温高压的热催化途径不同,光催化方法可以在温和条件下实现甲烷活化和选择性转化,是一种非常具有前景的可持续途径。然而,使用廉价光催化剂在流动条件下实现高效C_(2)化合物的生成仍然是一个巨大挑战。本文通过简单的化学还原法合成了一种具有超低负载量的AuPd合金纳米颗粒负载的TiO_(2)光催化剂(Au_(0.05)-Pd_(0.05)/TiO_(2)),用于光催化甲烷转化。在流动反应条件下,含水蒸气的甲烷可以高效转化为包括乙烷和乙烯在内的C_(2)化合物,C_(2)产率高达10092μmol·g^(−1)·h^(−1),选择性为77%。更重要的是,在反应持续32 h后,催化活性没有显著降低。Au_(0.05)-Pd_(0.05)/TiO_(2)的光催化甲烷转化的活性和稳定性超过了迄今为止报道的结果。Au_(0.05)-Pd_(0.05)/TiO_(2)良好的催化活性可以归因于金和钯的协同效应,不仅促进了光生载流子的分离而且有利于·CH_(3)的C―C键耦合进而产生C_(2)化合物。同时,引入水蒸气有助于及时补充在甲烷活化过程中消耗的晶格氧,从而保持催化剂的稳定性。这项工作有望为设计甲烷到C_(2)化合物的可持续光催化转化途径提供一个典范。

Characteristics of cross transmission of gut fungal pathogens between wintering Hooded Cranes and sympatric Domestic Geese

Migratory birds travel long distance and link various pathogens.Due to habitat degradation,wintering waterfowls forage together with poultry,increasing the risk of pathogen transmission between hosts.We investigated the fungal communities between wintering Hooded Cranes and Domestic Geese by high-throughput sequencing,and inferred the potential gut pathogens for both hosts at different wintering stages.The fungal community compositions were significantly different between seasons and between the hosts.The negative correlation was found between fungal diversity and pathogenic diversity,with higher fungal diversity and less pathogenic diversity in early stage and less fungal diversity and higher pathogenic diversity in late stage for both hosts.The dissimilarity of pathogenic community compositions decreased from early to late stage,with the quantity of overlapping potential pathogenic OTUs increasing along wintering periods between the two hosts,demonstrating the existence of pathogen cross transmission between the two hosts.Furthermore,the transmission pathway of avian pathogens was mainly from Hooded Cranes to Domestic Geese while the transmission direction of human pathogens was primarily from Domestic Geese to wild cranes.Based on above results,we argued that pathogen cross transmission and underlying outbreak risk of disease should be closely monitored in migratory birds and domestic poultry.

Unlocking supercapacitive energy storage potential:Catalyzing electrochemically inactive manganese oxides to active MnO_(2)via heterostructure reconstruction

Advancing supercapacitor system performance hinges on the innovation of novel electrode materials seamlessly integrated within distinct architectures.Herein,we introduce a direct approach for crafting nanorod arrays featuring crystalline/amorphous CuO/MnO_(2)−x.This reconfigured heterostructure results in an elevated content of electrochemically active MnO_(2).The nanorod arrays serve as efficient capacitive anodes and are easily prepared via low-potential electrochemical activation.The resulting structure spontaneously forms a p–n heterojunction,developing a built-in electric field that dramatically facilitates the charge transport process.The intrinsic electric field,in conjunction with the crystalline/amorphous architecture,enables a large capacitance of 1.0 F·cm^(−2)at 1.0 mA·cm^(−2),an ultrahigh rate capability of approximately 85.4%at 15 mA·cm^(−2),and stable cycling performance with 92.4%retention after 10,000 cycles.Theoretical calculations reveal that the presence of heterojunctions allows for the optimization of the electronic structure of this composite,leading to improved conductivity and optimized OH−adsorption energy.This work provides new insights into the rational design of heterogeneous nanostructures,which hold great potential in energy storage applications.

Unlocking single-atom catalysts via amorphous substrates

Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active sites.In general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target atoms.Recent studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic performance.In this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic activity.Firstly,we summarize the commonly used amorphous substrates for stabilizing SAs.Subsequently,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and photocatalysis.And then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic process.Finally,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.

Recent advances on aerobic photocatalytic methane conversion under mild conditions

Photocatalytic methane conversion to high value-added chemicals under mild conditions acts as a promising approach to utilize natural gas and renewable energy.Specifically,aerobic photocatalytic methane conversion that uses molecular oxygen as oxidant has attracted much attention because it is thermodynamic favorable and could generate various reactive oxygen species,resulting in many value-added products like methanol,formaldehyde,ethane,and ethylene.In this review,we classify the aerobic photocatalytic methane conversion into aerobic photocatalytic partial oxidation of methane(APPOM)and aerobic photocatalytic coupling of methane(APCM).We particularly focus on the fundamentals of oxygen activation and methane reaction modes in these conversions.Finally,we provide a brief summary for current challenges and future prospects towards aerobic photocatalytic methane conversion.

梗阻性左半结肠癌不同手术治疗方案的选择应用

梗阻性左半结肠癌是一种高发病率高死亡率的手术急症。传统上,针对其治疗以急诊手术为主。随着多学科诊疗模式的兴起和医疗技术的更新进步,手术治疗方案也呈现出多样化的趋势。经肛肠梗阻导管和自膨式金属支架的应用日益突出,将急诊手术转化为限期手术,并在临床治疗上取得了良好的效果,被广泛评价为"通往外科手术的桥梁"。对不同患者,在众多手术治疗方案中选择最适合的一项,从而改善短期预后及长期结局,是现阶段梗阻性左半结肠癌的主要研究方向也是治疗的重中之重。

结直肠癌粪便筛查的现状与展望

结直肠癌是世界范围内常见的消化系统恶性肿瘤之一,常因早期症状不易察觉或不典型而被忽视或延误诊治。近年来,以粪便为标本的非侵入性结直肠癌筛查方法因其简便、无创、经济等因素在基层及临床广泛开展。粪便隐血试验是目前结直肠癌非侵入性筛查中最重要的手段之一,其他粪便筛查方法仍待进一步研究和验证。多种方式的粪便筛查联合检测较单一方法表现出了更好的灵敏度,这提示可以联合多种非侵入性筛查方法构建结直肠癌筛查模型,以精确更适合行结肠镜检查的目标人群。本文就结直肠癌粪便筛查方法的现状及未来进行综述。

Hepatic and intestinal biotransformation gene expression and drug disposition in a dextran sulfate sodium-induced colitis mouse model

We examined the impact of gut inflammation on the expression of cytochrome P450(P450)and other biotransformation genes in male mice using a dextran sulfate sodium(DSS)-induced colitis model.Several P450 isoforms,including CYPIA,CYP2B,CYP2C,and CYP3A,were downregulated,accompanied by decreases in microsomal metabolism of diclofenac and nifedipine,in the liver and small intestine.The impact of the colitis on in vivo clearance of oral drugs varied for four different drugs tested:a small decrease for nifedipine,a relatively large decrease for lovastatin,but no change for pravastatin,and a large decrease in the absorption of cyclosporine A.To further assess the scope of influence of gut inflammation on gene expression,we performed genome-wide expression analysis using RNA-seq,which showed down-regulation of many CYPs,non-CYP phase-Ⅰenzymes,phase-Ⅱenzymes and transporters,and up-regulation of many other members of these gene families,in both liver and intestine of adult C57BL/6 mice,by DSS-induced colitis.Overall,our results indicate that gut inflammation suppresses the expression of many P450s and other biotransformation genes in the intestine and liver,and alters the pharmacokinetics for some but not all drugs,potentially affecting therapeutic efficacy or causing adverse effects in a drug-specific fashion.

Effect of Image Noise on the Classification of Skin Lesions Using Deep Convolutional Neural Networks

Skin lesions are in a category of disease that is both common in humans and a major cause of death.The classification accuracy of skin lesions is a crucial determinant of the success rate of curing lethal diseases.Deep Convolutional Neural Networks(CNNs)are now the most prevalent computer algorithms for the purpose of disease classification.As with all algorithms,CNNs are sensitive to noise from imaging devices,which often contaminates the quality of the images that are fed into them.In this paper,a deep CNN(Inception-v3)is used to study the effect of image noise on the classification of skin lesions.Gaussian noise,impulse noise,and noise made up of a compound of the two are added to an image dataset,namely the Dermofit Image Library from the University of Edinburgh.Evaluations,based on t-distributed Stochastic Neighbor Embedding(t-SNE)visualization,Receiver Operating Characteristic(ROC)analysis,and saliency maps,demonstrate the reliability of the Inception-v3 deep CNN in classifying noisy skin lesion images.

The key role of gut-liver axis in pyrrolizidine alkaloid-induced hepatotoxicity and enterotoxicity

Pyrrolizidine alkaloids(PAs) are the most common phytotoxins with documented human hepatotoxicity.PAs require metabolic activation by cytochromes P450 to generate toxic intermediates which bind to proteins and form protein adducts,thereby causing cytotoxicity.This study investigated the role of the gut-liver axis in PA intoxication and the underlying mechanisms.We exposed mice to retrorsine(RTS),a representative PA,and for the first time found RTS-induced intestinal epithelium damage and disruption to intestinal barrier function.Using mice with tissue-selective ablation of P450 activity,we found that hepatic P450 s,but not intestinal P450 s,were essential for PA bioactivation.Besides,in RTS-exposed,bile duct-cannulated rats,we found the liver-derived reactive PA metabolites were transported by bile into the intestine to exert enterotoxicity.The impact of gut-derived pathogenic factors in RTS-induced hepatotoxicity was further studied in mice with dextran sulfate sodium(DSS)-induced chronic colitis.DSS treatment increased the hepatic endotoxin level and depleted hepatic reduced glutathione,thereby suppressing the PA detoxification pathway.Compared to RTS-exposed normal mice,the colitic mice displayed more severe RTS-induced hepatic vasculature damage,fibrosis,and steatosis.Overall,our findings provide the first mode-of-action evidence of PA-induced enterotoxicity and highlight the importance of gut barrier function in PA-induced liver injury.