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Phenylhydrazone anions excitation for the photochemical carbonylation of aryl iodides with aldehydes

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Chinese Chemical Letters 2024年第4期35卷 346-351页

作者： Lei Shen yang Zhang Linlin Zhang Chuanwang Liu zhixian Ma Kangjiang Liang Chengfeng Xia Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of EducationYunnan Provincial Center for Research&Development of Natural ProductsSchool of PharmacyYunnan UniversityKunming 650500China

Spectroscopic investigations discovered that the in-situ generated phenylhydrazone anion was significantly bathochromically shifted to visible light region for photoactivation under irradiation. The photoexcited phenylhydrazone anion was potential to reduce aryl iodides via single electron transfer process for the subsequent radical chain reaction. A redox-neutral photochemical carbonylation of aryl iodides was developed on basis of the special spectroscopic features of phenylhydrazone anion. This protocol provided a convenient and efficient synthetic tool for accessing carbonylation products under redox neutral conditions without the need of transition-metals.

关键词： Organic anion Hydrazone Carbonylation Visible light Single electron transfer

Experimental study and numerical simulation of the impact of under-sleeper pads on the dynamic and static mechanical behavior of heavy-haul railway ballast track

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Railway Engineering Science 2024年第3期32卷 384-400页

作者： Yihao Chi Hong Xiao yang Wang zhihai Zhang Mahantesh M.Nadakatti School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Beijing Key Laboratory of Track Engineering Beijing Jiaotong UniversityBeijing 100044China Department of Mechanical Engg KLSGITBelgaumKarnataka 590008India

Laying the under-sleeper pad(USP)is one of the effective measures commonly used to delay ballast degradation and reduce maintenance *** explore the impact of application of the USP on the dynamic and static mechanical behavior of the ballast track in the heavy-haul railway system,numerical simulation models of the ballast bed with USP and without USP are presented in this paper by using the discrete element method(DEM)-multi-flexible body dynamic(MFBD)coupling analysis *** ballast bed support stiffness test and dynamic displacement tests were carried out on the actual operation of a heavy-haul railway line to verify the validity of the *** results show that using the USP results in a 43.01%reduction in the ballast bed support stiffness and achieves a more uniform distribution of track loads on the *** effectively reduces the load borne by the sleeper directly under the wheel load,with a 7.89%reduction in the pressure on the ***,the laying of the USP changes the lateral resistance sharing ratio of the ballast bed,significantly reducing the stress level of the ballast bed under train loads,with an average stress reduction of 42.19 *** also reduces the plastic displacement of ballast particles and lowers the peak value of rotational angular velocity by about 50%to 70%,which is conducive to slowing down ballast bed settlement deformation and reducing maintenance *** summary,laying the USP has a potential value in enhancing the stability and extending the lifespan of the ballast bed in heavy-haul railway systems.

关键词： Heavy-haul railway Under-sleeper pad Discrete element method Multi-flexible body dynamic coupling analysis Mechanical behavior Quality state

High mechanical strength Si anode synthesis with interlayer bonded expanded graphite structure for lithium-ion batteries

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Journal of Energy Chemistry 2024年第6期93卷 253-263,I0007页

作者： Wenhui Lai Jong Hak Lee Lu Shi Yuqing Liu Yanhui Pu yong Kang Ong Carlos Limpo Ting Xiong Yifan Rao Chorng Haur Sow Barbaros Ozyilmaz Department of Material Science&Engineering National University of SingaporeSingapore 117575Singapore Center for Advanced 2D Materials National University of SingaporeSingapore 117546Singapore Department of Physics National University of SingaporeSingapore 117551Singapore Institute forFunctional Intelligent Materials National University of SingaporeSingapore 117544Singapore

Despite advancements in silicon-based anodes for high-capacity lithium-ion batteries,their widespread commercial adoption is still hindered by significant volume expansion during cycling,especially at high active mass loadings crucial for practical *** root of these challenges lies in the mechanical instability of the material,which subsequently leads to the structural failure of the ***,we present a novel synthesis of a composite combining expanded graphite and silicon *** composite features a unique interlayer-bonded graphite structure,achieved through the application of a modified spark plasma sintering ***,this innovative structure not only facilitates efficient ion and electron transport but also provides exceptional mechanical strength(Vickers hardness:up to658 MPa,Young's modulus:11.6 GPa).This strength effectively accommodates silicon expansion,resulting in an impressive areal capacity of 2.9 mA h cm^(-2)(736 mA h g^(-1)) and a steady cycle life(93% after 100cycles).Such outsta nding performance is paired with features appropriate for large-scale industrial production of silicon batteries,such as active mass loading of at least 3.9 mg cm^(-2),a high-tap density electrode material of 1.68 g cm^(-3)(secondary clusters:1.12 g cm^(-3)),and a production yield of up to 1 kg per day.

关键词： Lithium-ion battery Silicon anode Spark plasma sintering Interlayer bonding Mechanical strength Tap density

Study on the preservation effects of the amputated forelimb by machine perfusion at physiological temperature

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Chinese Journal of Traumatology 2024年第2期27卷 114-120页

作者： Sheng-Feng Chen Bo-Yao yang Tie-Yuan Zhang Xiang-Yu Song zhi-Bo Jia Lei-Jia Chen Meng-Yi Cui Wen-Jing Xu Jiang Peng Guizhou Medical University Guiyang550025China Medical School of PLA Beijing100048 China Beijing Key Lab of Regenerative Medicine in Orthopedics Key Laboratory of Musculoskeletal Trauma and War Injuries PLADepartment of OrthopedicsThe Fourth Medical CenterChinese PLA General HospitalBeijing100048China Hebei North Universiy Zhangjiakou075000Hebei ProvinceChina

Purpose:Ischemia and hypoxia are the main factors limiting limb replantation and *** cold storage(SCS),a common preservation method for tissues and organs,can only prolong limb ischemia time to 4-6 *** normothermic machine perfusion(NMP)is a promising method for the preservation of tissues and organs,which can extend the preservation time in vitro by providing continuous oxygen and *** study aimed to evaluate the difference in the efficacy of the 2 limb preservation ***:The 6 forelimbs from beagle dogs were divided into 2 *** the SCS group(n=3),the limbs were preserved in a sterile refrigerator at 4°C for 24 h,and in the NMP group(n=3),the perfusate prepared with autologous blood was used for the oxygenated machine perfusion at physiological temperature for 24 h,and the solution was changed every 6 *** effects of limb storage were evaluated by weight gain,perfusate biochemical analysis,enzyme-linked immunosorbent assay,and histological *** statistical analyses and graphs were performed using GraphPad Prism 9.0 one-way or two-way analysis of *** p value of less than 0.05 was considered to indicate statistical ***:In the NMP group,the weight gained percentage was 11.72%±4.06%;the hypoxia-inducible factor-1αcontents showed no significant changes;the shape of muscle fibers was normal;the gap between muscle fibers slightly increased,showing the intercellular distance of(30.19±2.83)μm;and the vascularα-smooth muscle actin(α-SMA)contents were lower than those in the normal blood *** creatine kinase level in the perfusate of the NMP group increased from the beginning of perfusion,decreased after each perfusate change,and remained stable at the end of perfusion showing a peak level of 4097.6 U/*** lactate dehydrogenase level of the NMP group increased near the end of perfusion and reached the peak level of 374.4 U/*** the SCS group,the percentage of weight gain was 0.18%±0.10%,a

关键词： Traumatic amputation Machine perfusion Static cold storage Limb replantation

Optogenetics in oral and craniofacial research

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第8期25卷 656-671页

作者： Qinmeng ZHANG Luyao SONG Mengdie FU Jin HE Guoli yang zhiwei JIANG Stomatology Hospital School of StomatologyZhejiang University School of MedicineZhejiang Provincial Clinical Research Center for Oral DiseasesKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityHangzhou 310000China Zhejiang University School of Medicine Hangzhou 310058China

Optogenetics combines optics and genetic engineering to control specific gene expression and biological functions and has the advantages of precise spatiotemporal control,noninvasiveness,and high *** modified photosensory sensors are engineered into proteins to modulate conformational changes with light ***,optogenetic techniques can provide new insights into oral biological processes at different levels,ranging from the subcellular and cellular levels to neural circuits and behavioral ***,we introduce the origins of optogenetics and highlight the recent progress of optogenetic approaches in oral and craniofacial research,focusing on the ability to apply optogenetics to the study of basic scientific neural mechanisms and to establish different oral behavioral test models in vivo(orofacial movement,licking,eating,and drinking),such as channelrhodopsin(ChR),archaerhodopsin(Arch),and halorhodopsin from Natronomonas pharaonis(NpHR).We also review the synergic and antagonistic effects of optogenetics in preclinical studies of trigeminal neuralgia and maxillofacial *** addition,optogenetic tools have been used to control the neurogenic differentiation of dental pulp stem cells in translational *** the scope of optogenetic tools is increasing,there are limited large animal experiments and clinical studies in dental *** future directions include exploring therapeutic strategies for addressing loss of taste in patients with coronavirus disease 2019(COVID-19),studying oral bacterial biofilms,enhancing craniomaxillofacial and periodontal tissue regeneration,and elucidating the possible pathogenesis of dry sockets,xerostomia,and burning mouth syndrome.

关键词： Lasers Cell differentiation Bacterial virulence Nervous system Neurophysiology Behavioral science

Recent advancements in understanding of biological role of homeobox C9 in human cancers

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World Journal of Clinical Oncology 2024年第9期15卷 1168-1176页

作者： yong Zhang Jing Li Department of Clinical Laboratory The Affiliated Lianyungang Oriental Hospital of Kangda College of Nanjing Medical UniversityLianyungang 222042Jiangsu ProvinceChina Department of Respiratory and Critical Care Medicine The Affiliated Lianyungang Oriental Hospital of Kangda College of Nanjing Medical UniversityLianyungang 222042Jiangsu ProvinceChina

Homeobox(HOX)C9,a member of the HOX family,is an important transcription factor,and it plays a significant role in various biological *** family of genes is highly valued for their essential roles in establishing and maintaining the body axis during embryonic development and adult ***,HOXC9 plays a central role in neuronal differentiation,angiogenesis,and adipose distribution,which are essential for the development of the nervous system,maturation of tissues and organs,and maintenance of energy balance and metabolic *** research has found that abnormal HOXC9 expression is closely associated with the development and progression of various tumor *** HOXC9 expression level can be an indicator of tumor ***,elucidating the association between HOXC9 expression and its regulatory mechanisms and tumorigenesis can provide novel insights on the diagnosis and treatment of patients with cancer.

关键词： Homeobox C9 Proliferation Invasion Malignant tumor Molecular mechanism

Clinical effect of acupuncture at ghost points combined with fluoxetine hydrochloride on mild-to-moderate depression

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World Journal of Psychiatry 2024年第6期14卷 848-856页

作者： Yi Wang Qun Lu Ittipalanukul Penpat Juan Wu Dilinuer Abulikemu Fei-Cui Zeng Jia-Ying Huang zhi-Hai Hu Department of Acupuncture and Moxibustion Shanghai Hospital of Integrated Traditional Chinese and Western MedicineThe Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200082China Department of Laboratory Medicine Shanghai Hospital of Integrated Traditional Chinese and Western MedicineThe Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200082China Department of Postgraduate Student Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Radiology Shanghai Hospital of Integrated Traditional Chinese and Western MedicineThe Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200082China Department of General Practice Shanghai University of Traditional Chinese Medicine Affiliated Shuguang HospitalShanghai 200120China General Practice of Traditional Chinese Medicine North Bund Street Community Health Service CenterShanghai 200080China General Practice of Traditional Chinese Medicine Shanghai Hongkou District Jiaxing Road Community Health Service CenterShanghai 200082China

BACKGROUND Depression is a common,chronic,and recurrent mood disorder that has become a worldwide health *** hydrochloride,a common treatment method,can inhibit 5-hydroxytryptamine(5-HT)recycling in the presynaptic membrane;however,the efficacy of a single drug is *** present,mildto-moderate depression can be treated with acupuncture of ghost caves,but the clinical curative effect of combined therapy with fluoxetine hydrochloride has not been sufficiently *** To evaluate the clinical effect of acupuncture at ghost points combined with fluoxetine hydrochloride in the treatment of mild-to-moderate *** This retrospective study included 160 patients with mild-to-moderate depression who were admitted to Shanghai Hospital of Integrated Traditional Chinese and Western Medicine,Affiliated to Shanghai University of Traditional Chinese Medicine,between January 2022 and June *** were separated into a single-agent group(fluoxetine hydrochloride treatment,n=80)and a coalition group(fluoxetine hydrochloride treatment combined with acupuncture at ghost points,n=80).Pre-treatment symptoms were recorded,and the clinical curative effect and adverse reactions[Asberg Antidepressant Side Effects Scale(SERS)]were *** before and after treatment[Hamilton Depression Scale(HAMD)-24],neurotransmitter levels[5-HT,norepinephrine(NE),dopamine(DA)],oxidative stress indicators[superoxide dismutase(SOD),malondialdehyde(MDA)],and sleep quality[Pittsburgh Sleep Quality Index(PSQI)]were *** The total efficacy rate was 97.50%in the coalition group and 86.25%in the single-agent group(P<0.05).After 2,4,6,and 8 wk of treatment,the HAMD,self-rating depression scale,and SERS scores of the coalition and single-agent groups decreased compared with pre-treatment,and the decrease was more significant in the coalition group(P<0.05).After 8 wk of treatment,the levels of NE,DA,5-HT,and SOD in the coalition and single-agent group

关键词： Depression Prick Fluoxetine hydrochloride Curative effect Depressive symptoms Oxidative stress index

The coordinated evolution of ecological environment,public service,and tourism economy along the Silk Road Economic Belt,using the Dual-Carbon Targets

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 34-47页

作者： Shuo yang Wei Guo Tianjun Xu Tongtong Liu School of Economic and Management Yanshan UniversityQinhuangdao 066004China Regional Economic Development Center Yanshan UniversityQinhuangdao 066004China

Carbon peak and carbon neutrality(dual-carbon)are important targets for the international response to climate *** Silk Road Economic Belt is a strategic resource region and is important for future ecological environment and tourism *** on the“dual-carbon”targets,the Single index quantification,Multiple index synthesis,and Poly-criteria integration evaluation model were used in this study to measure the coordinated development index of the ecological environment,public service,and tourism economy along the Silk Road Economic Belt and to analyze its spatial and temporal ***,it explores the dynamic evolution and development trend of the three systems using the Kernel Density and Grey Markov Prediction *** results show that the coordinated development index along this region needs to be improved during the study ***,the coordinated development index of the Southwest region is relatively higher than that of the Northwest *** the development trend of the three systems,all of them develop in a stable manner;however,the tourism economy system is easily affected by external *** coordinated development index of the three systems changes dynamically and tends to be in a good state of *** is a certain spatial and temporal *** gravity center of the coordinated development index has been in the Southwest *** the forecast period,the coordinated development index along this region will improve significantly,while insufficient and unbalanced development will continue.

关键词： Dual-carbon Ecological environment Public services Tourist economy Silk Road Economic Belt

Time-resolved Spectral Properties of Fermi-GBM Bright Long Gamma-Ray Bursts

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Research in Astronomy and Astrophysics 2024年第2期24卷 58-73页

作者： Wan-Kai Wang Wei Xie zhi-Fu Gao Shuo Xiao Ai-Jun Dong Bin Zhang Qi-Jun zhi Department of Astronomy School of Physics and Electronic ScienceGuizhou Normal UniversityGuiyang 550001China Guizhou Provincial Key Laboratory of Radio Astronomy Data Processing Guizhou Normal UniversityGuiyang 550001China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

The prompt emission mechanism of gamma-ray bursts(GRBs)is still unclear,and the time-resolved spectral analysis of GRBs is a powerful tool for studying their underlying physical *** performed a detailed time-resolved spectral analysis of 78 bright long GRB samples detected by Fermi/Gamma-ray Burst Monitor.A total of 1490 spectra were obtained and their properties were studied using a typical Band-shape ***,the parameter distributions of the time-resolved spectrum are given as follows:the low-energy spectral indexα~-0.72,high-energy spectral indexβ~2.42,the peak energy E_(p)~221.69 keV,and the energy flux F~7.49×10^(-6)erg cm^(-2)s^(-1).More than 80%of the bursts exhibit the hardest low-energy spectral indexα_(max),exceeding the synchrotron limit(-2/3).Second,the evolution patterns of a and E_(p)were statistically *** results show that for multi-pulse GRBs the intensity-tracking pattern is more common than the hard-to-soft pattern in the evolution of both E_(p)andα.The hard-to-soft pattern is generally shown in single-pulse GRBs or in the initial pulse of multi-pulse ***,we found a significant positive correlation between F and E_(p),with half of the samples exhibiting a positive correlation between F andα.We discussed the spectral evolution of different radiation *** diversity of spectral evolution patterns indicates that there may be more than one radiation mechanism occurring in the GRB radiation process,including photo spheric radiation and synchrotron ***,it may also involve only one radiation mechanism,but more complicated physical details need to be considered.

关键词： (stars:)gamma-ray burst general-methods statistical-methods data analysis