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CCS Chemistry 2024年第4期6卷 1060-1070页

作者： Sifan Li Hai-Wu Du Paul W.Davies wei shu Department of Chemistry Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhen 518055Guangdong School of Chemistry University of BirminghamEdgbastonBirmingham B152TT

Sterically congestedα-tertiary primary amines are ubiquitous substructures in pharmaceutical and agrochemical agents yet are challenging to access.Herein,straightforward photoredox-catalyzed access to structurally diverseα,α,α-trisubstituted primary amines from denitrogenative alkylarylation or dialkylation of vinyl azides with N-hydroxyphthalimide(NHPI)esters and cyanoarenes or aryl aldehydes has been developed.The use of vinyl azide as a precursor to a primary aminewas enabled by the dual role of the Hantzsch ester to form an electron donor-acceptor complex and serve as a sacrificial reductant.This strategy provides a modular synthesis ofα-tertiary primary amines,including unprotected 1,2-amino alcohols,from simple materials with excellent functional group tolerance.The synthetic applicability of this method was demonstrated by streamlined access to 2,2-disubstituted tetrahydroquinolines.Preliminary investigations support two parallel reductive photocatalytic cycles allowing for the denitrogenative alkylarylation or dialkylation of vinyl azides via decarboxylative radical addition followed by heteroradical cross-coupling betweenα-amino radicals and aryl anion radicals or ketyl anion radicals.

关键词： photocatalysis α-tertiary primary amines 1 2-amino alcohols vinyl azide electron donor-acceptor complex

A Semiparametric Additive-multiplicative Rates Model for the weighted Composite Endpoint of Recurrent and Terminal Events

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Acta Mathematica Sinica,English Series 2024年第4期40卷 985-999页

作者： Yi DENG Qiang XIONG shu wei LI School of Economics and Statistics Guangzhou UniversityGuangzhou 510006P.R.China

Recurrent event data are commonly encountered in many scientific fields,including biomedical studies,clinical trials and epidemiological surveys,and many statistical methods have been proposed for their analysis.In this paper,we consider to use a weighted composite endpoint of recurrent and terminal events,which is weighted by the severity of each event,to assess the overall effects of covariates on the two types of events.A flexible additive-multiplicative model incorporating both multiplicative and additive effects on the rate function is proposed to analyze such weighted composite event process,and more importantly,the dependence structure among the recurrent and terminal events is left unspecified.For the estimation,we construct the unbiased estimating equations by virtue of the inverse probability weighting technique,and the resulting estimators are shown to be consistent and asymptotically normal under some mild regularity conditions.We evaluate the finite-sample performance of the proposed method via simulation studies and apply the proposed method to a set of real data arising from a bladder cancer study.

关键词： Additive-multiplicative rates model estimating equation recurrent events terminal event weighted composite endpoint

Both host and diet shape bacterial communities of predatory mites

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Insect Science 2024年第2期31卷 551-561页

作者： Hong Yan Endong Wang Guo-shu wei Bo Zhang Xuenong Xu Institute of Plant Protection Chinese Academy of Agricultural SciencesBejingChina College of Plant Protection Hebei Agricultural UniversityBaodingHebei ProvinceChina Key Laboratory of Natural Enemies Insects Ministry of Agriculture and Rural AffairsBeijingChina

Microbial communities,derived from food,ambient,and inner,can affect host ecological adaption and evolution.Comparing with most phytophagous arthropods,predators may have more opportunities to develop specific microbiota depending on the level of prey specialization.To explore how diet sources affect host microbial communities and vary across predator species,we considered 3 types of predators from Phytoseiidae(Acari:Mesostigmata):polyphagous(Amblyseius orientalis Ehara,Neoseiulus barkeri Hughes,and Amblyseius swirski Athias-Henrio),oligophagous(Neoseiulus californicus McGregor),and monophagous(Phytoseiulus persimilis Athias-Henriot)predatory mites.The polyphagous species were fed on 2 types of diets,natural prey and alternative prey.By using 16S rRNA sequencing,we found that diet was the main source of microbiota in predatory mites,while there was no clear pattern affected by prey specialization.Among 3 polyphagous predators,host species had a larger impact than prey on microbial composition.Unlike A.orientalis or N.barkeri which showed consistency in their microbiota,prey switching significantly affectedβ-diversity of bacterial composition in A.swirskii,with 56%of the microbial alteration.In short,our results confirmed the substantial influence of diet on host microbial construction in predatory species,and highlighted species differences in shaping the microbiota which are not necessarily related to prey specialization.

关键词： diet switching feeding habits host-microbial interactions invertebrate microbiota 16S rRNA

Application of artifcial intelligence in cataract management:current and future directions

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Eye and Vision 2024年第1期10卷 21-30页

作者： Laura Gutierrez Jane Sujuan Lim Li Lian Foo wei Yan Ng Michelle Yip Gilbert Yong San Lim Melissa Hsing Yi Wong Allan Fong Mohamad Rosman Jodhbir Singth Mehta Haotian Lin Darren shu Jeng Ting Daniel shu wei Ting Singapore Eye Research Institute SingaporeSingapore Singapore National Eye Center 11 Third Hospital AvenueSingapore 168751Singapore Academic Ophthalmology School of MedicineUniversity of NottinghamNottinghamUK Zhongshan Ophthalmic Center Sun Yet Sen UniversityGuangzhouChina

The rise of artifcial intelligence(AI)has brought breakthroughs in many areas of medicine.In ophthalmology,AI has delivered robust results in the screening and detection of diabetic retinopathy,age-related macular degeneration,glaucoma,and retinopathy of prematurity.Cataract management is another feld that can beneft from greater AI application.Cataract is the leading cause of reversible visual impairment with a rising global clinical burden.Improved diagnosis,monitoring,and surgical management are necessary to address this challenge.In addition,patients in large developing countries often sufer from limited access to tertiary care,a problem further exacerbated by the ongoing COVID-19 pandemic.AI on the other hand,can help transform cataract management by improving automation,efcacy and overcoming geographical barriers.First,AI can be applied as a telediagnostic platform to screen and diagnose patients with cataract using slit-lamp and fundus photographs.This utilizes a deep-learning,convolutional neural network(CNN)to detect and classify referable cataracts appropriately.Second,some of the latest intraocular lens formulas have used AI to enhance prediction accuracy,achieving superior postoperative refractive results compared to traditional formulas.Third,AI can be used to augment cataract surgical skill training by identifying diferent phases of cataract surgery on video and to optimize operating theater workfows by accurately predicting the duration of surgical procedures.Fourth,some AI CNN models are able to efectively predict the progression of posterior capsule opacifcation and eventual need for YAG laser capsulotomy.These advances in AI could transform cataract management and enable delivery of efcient ophthalmic services.The key challenges include ethical management of data,ensuring data security and privacy,demonstrating clinically acceptable performance,improving the generalizability of AI models across heterogeneous populations,and improving the trust of end-users.

关键词： Artifcial intelligence Telemedicine Cataract Cataract screening Cataract surgery IOL calculations Biometry Machine learning

Rapid Access to Free Phenols by Photocatalytic Acceptorless Dehydrogenation of Cyclohexanones at Room Temperature

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Chinese Journal of Chemistry 2023年第21期41卷 2773-2778页

作者： Lin Min Jiani Lin wei shu Shenzhen Grubbs Institute Department of Chemistryand Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhenGuangdong518055 China

Phenols are ubiquitous substructures in natural products and bioactive compounds.However,practical methods for the direct construction of phenols under mild conditions remain challenging.Herein,a photocatalytic acceptorless hydrogen-evolution aromatization of cyclohexanones or cyclohexenones at room temperature has been developed.The reaction features the visible-light and cobalt co-catalyzed sequential dehydrogenation of in-situ formed enol silyl ethers,which are regarded as a challenging process.This operationally simple method enables the synthesis of a series of phenols with diverse substitution patterns from cyclohexanones or cyclohexenones.Moreover,diverse substituted 1,2-,1,3-,and 1,4-benzenediols were obtained from cyclohexanediones,providing a general and straightforward method for the synthesis of phenols from simple starting materials under mild conditions.

关键词： Phenols Photocatalysis Dehydrogenation Cyclohexanones Cobalt catalysis Radicals

Thermoelectric transport properties of p-type Bi2Se3-Sb2Se3-In2Se3 high entropy compounds

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Rare Metals 2024年第7期43卷 3415-3421页

作者： Feng Jiang Cheng-Liang Xia Yong-Bin Zhu Jun Li Yue Chen wei-shu Liu Department of Materials Science and Engineering Southern University of Science and Technology Department of Mechanical Engineering The University of Hong Kong Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology

The introduction of entropy concept into thermoelectric materials recently has attracted broad interest.Herein,we showed the phase diagram of the ternary systems of Bi2Se3-Sb2Se3-In2Se3.Among the high entropy compounds （HECs）,we have identified an intrinsic p-type region near our previously reported Bi0.8Sb0.8In0.4Se3in the phase diagram.

关键词： Selenium compounds

Molecular dynamics simulations on the interactions between nucleic acids and a phospholipid bilayer

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Chinese Physics B 2024年第2期33卷 512-521页

作者：徐耀黄舒伟丁泓铭马余强 National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Center for Soft Condensed Matter Physics and Interdisciplinary Research School of Physical Science and TechnologySoochow UniversitySuzhou 215006China

Recently,lipid nanoparticles(LNPs)have been extensively investigated as non-viral carriers of nucleic acid vaccines due to their high transport efficiency,safety,and straightforward production and scalability.However,the molecular mechanism underlying the interactions between nucleic acids and phospholipid bilayers within LNPs remains elusive.In this study,we employed the all-atom molecular dynamics simulation to investigate the interactions between single-stranded nucleic acids and a phospholipid bilayer.Our findings revealed that hydrophilic bases,specifically G in single-stranded RNA(ssRNA)and single-stranded DNA(ssDNA),displayed a higher propensity to form hydrogen bonds with phospholipid head groups.Notably,ssRNA exhibited stronger binding energy than ssDNA.Furthermore,divalent ions,particularly Ca2+,facilitated the binding of ssRNA to phospholipids due to their higher binding energy and lower dissociation rate from phospholipids.Overall,our study provides valuable insights into the molecular mechanisms underlying nucleic acidphospholipid interactions,with potential implications for the nucleic acids in biotherapies,particularly in the context of lipid carriers.

关键词： RNA DNA lipid bilayer molecular dynamics interface interaction divalent cation

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数字化转型与企业商业信用融资行为研究

会计研究 2024年第1期 79-93页

作者：舒伟陈颖西安财经大学商学院 710100 上海立信会计金融学院会计学院 201620

基于中国上市公司2013-2019年数据,借助文本分析方法构建企业数字化转型指标,考察数字化转型对商业信用融资的影响及作用机制。研究表明企业数字化转型与商业信用融资显著正相关。作用机制发现数字化转型通过降低企业信息风险、优化企... 详细信息

基于中国上市公司2013-2019年数据,借助文本分析方法构建企业数字化转型指标,考察数字化转型对商业信用融资的影响及作用机制。研究表明企业数字化转型与商业信用融资显著正相关。作用机制发现数字化转型通过降低企业信息风险、优化企业经营效率,从而实现商业信用融资的提升效应。异质性考察发现,数字化转型提升商业信用的效应在金融欠发达地区、竞争程度激烈的行业及国有企业中更加显著。价值效应检验发现,数字化转型改善商业信用融资,减少了对债务融资的需求,具有一定的融资价值效应。本文为理解数字时代企业转型行为提供经验支持,揭示数字化应用对商业信用融资的作用机制及经济后果,为促进数字经济与实体经济融合提供微观证据。

关键词：数字化转型企业融资商业信用

笃志创新躬行致远:世界卫生组织《2023年全球结核病报告》结核病科学研究章节解读

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中国防痨杂志 2024年第6期46卷 613-617页

作者：舒薇刘宇红首都医科大学附属北京胸科医院/北京市结核病胸部肿瘤研究所/中国疾病预防控制中心结核病防治临床中心北京101149

结核病领域创新性的研究与发展是终止结核病策略三大支柱之一,新技术和新策略是加速消除结核病进程的重要工具。2023年11月7日,世界卫生组织发布了《2023年全球结核病报告》,对全球结核病的流行情况,以及全球、区域和国家各级在预防、... 详细信息

结核病领域创新性的研究与发展是终止结核病策略三大支柱之一,新技术和新策略是加速消除结核病进程的重要工具。2023年11月7日,世界卫生组织发布了《2023年全球结核病报告》,对全球结核病的流行情况,以及全球、区域和国家各级在预防、诊断和治疗结核病方面取得的进展进行更新。笔者就报告中结核病研究领域新诊断技术、新药与新方案及新疫苗等的研究及创新要点进行综述,并结合我国相关领域的研究进展进行分析,以期为我国结核病防治领域同行掌握结核病研究动态,进一步开展原创性研究和技术提供参考。

关键词：结核研究总结性报告

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社会政策中的利益分配、阶层分化与国民生存境遇——基于2017中国社会状况综合调查数据

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南京社会科学 2024年第4期 83-97页

作者：魏姝朱茂莹南京大学政府管理学院南京210023

当下中国社会的主要矛盾已经发生关系全局的重大转变。这一转变要求党和政府在保持经济平稳运行的同时,更加注重民生建设和改善国民生存境遇。国民生存境遇受到哪些因素影响?其作用机制是怎样的?为了回答这一问题,本文基于社会政策视域... 详细信息

当下中国社会的主要矛盾已经发生关系全局的重大转变。这一转变要求党和政府在保持经济平稳运行的同时,更加注重民生建设和改善国民生存境遇。国民生存境遇受到哪些因素影响?其作用机制是怎样的?为了回答这一问题,本文基于社会政策视域,在整合经济学和社会学相关理论的基础上,构建了“利益分配-阶层分化-生存境遇”分析框架并进行了实证研究。结果表明,国民生存境遇的好坏取决于利益分配结构和社会相对位置。在初始性分配中,文化资本的作用相对更强,而空间资本和社会资本的作用相对较弱。在制度性再分配中,政府相关工作对国民生存境遇也有显著的正向影响。社会阶层在利益分配与国民生存境遇的关系中起到部分中介作用,但这种中介作用在不同收入水平的家庭中存在差异。改善国民生存境遇,关键在于初始性分配和制度性再分配的良性互动以及政府主导的“再商品化”和“去商品化”策略的优势互补。通过降低概念测量的笼统性、即时性和波动性,在致因分析中贯通从“资本”到“惯习”再到“境遇”的研究路径,既为理论上检视经济学、社会学等不同学科视角下国民境遇的影响因素及其作用机理提供经验证据,也为实践层面进一步改善民生建设提供有针对性的决策参考。

关键词：生存境遇社会政策利益分配阶层分化