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Transition-metal-free hydroamination/defluorination/cyclization of perfluoroalkyl alkynes with amidines

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Organic Chemistry Frontiers 2022年第1期9卷 109-116页

作者： Li-Wen Sun zi-Lun Yu xin-Long luo Mengtao Ma Zhi-Liang Shen xue-Qiang Chu Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China Department of Chemistry and Materials Science College of ScienceNanjing Forestry UniversityNanjing 210037China

An efficient defluorinative net-[3+3]-cyclization strategy for the construction of perfluoroalkyl-substituted pyrimidine derivatives by using a series of perfluoroalkyl alkynes and amidines as starting materials was *** present reaction proceeded successfully under transition-metal-free conditions to form two new C–N bonds and a new heterocyclic ring through a sequence of hydroamination,defluorination,and *** desired pyrimidines could be obtained with good functional group tolerance and moderate to good ***,the distinctive fluorine effects of perfluoroalkyl substituents are vital for tuning the reactivity of alkynes for the anticipated defluorinative *** pendantπsystem would lower associated bond dissociation energy significantly compared to that of a nonactivated C(sp^(3))–F bond.

关键词： cyclization pyrimidine Transition

Global trends and knowledge-relationship of symptom clusters in cancer research:a bibliometric analysis over the past 20 years

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Frontiers of Nursing 2023年第3期10卷 273-288页

作者： Ran An Yuan luo Wen-Feng Chen Muhammad Sohaib Mei-zi Liu xiangya School of Nursing Central South UniversityChangshaHunan 410013China Teaching and Research Section of Clinical Nursing Xiangya Hospital Central South UniversityChangshaHunan 410013China Children Hospital and Institute of Child Health Multan 60000Pakistan

Objective:To use Cite Space and VOSviewer to investigate the scientific production in the field of symptom clusters in cancer ***:The search was performed using the terms“symptom clusters,”“cancer,”and“oncology”on the Web of Science Core Collection *** retrieval time was from 2001 to 2021,which covers the last 2 *** on the production theory of scientific knowledge and the data mining of citations,data pertaining to the annual publications,journals,countries,organizations,authors,and keywords that produce symptom clusters in cancer research,as well as their cooperation(collaboration network),were extracted,and then both were clarified by the software tools VOSviewer(version 1.6.16)and Cite Space(version 6.1.R2).Results:A total of 1796 publications were retrieved between 2001 and 2021,and 473 relevant publications were included after *** results showed an increasing trend in published *** United States had the largest number of publications(261/473,55.18%),followed by China and *** University of California,San Francisco,was the most productive *** research hotspots included the analysis of symptom clusters and symptom management in patients with breast cancer and lung cancer,as well as any advanced cancer and cancer cachexia;fatigue-related symptom clusters and depression-anxiety symptom cluster;and the impacts of symptom clusters on quality of *** research frontiers included analysis between health-related quality of life and symptom clusters,data mining in symptom clusters,research on the mental health status of cancer patients,and study of the mechanism and biological pathways of symptom ***:The study provides insight into the global research perspective for the scientific progress on cancer symptom clusters,which suggests a growing scientific interest in this field,and more studies are warranted to guide symptom management.

关键词： bibliometrics cancer Citespace symptom clusters systematic review VOSviewer

Characteristics of rock fragments in different forest stony soil and its relationship with macropore characteristics in mountain area, northern China

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Journal of Mountain Science 2018年第3期15卷 519-531页

作者： MENG Chen NIU Jian-zhi YIN Zheng-cong luo zi-teng LIN xing-na JIA Jing-wei College of Soil and Water Conservation Beijing Forestry University Beijing Collaborative Innovation Center for Eco-environmental Improvement with Forestry and Fruit Trees Beijing University of Agriculture Department of Geography Texas A&M University College Station

Rock fragments have major effect on soil macropores and water movement. However, the characteristics of rock fragments and their relationship with macropore characteristics remain elusive in forest stony soils in northern mountainous area of China. The objectives of this study are to(1) use Industrial Computed Tomography(CT) scanning to quantitatively analyze rock fragment characteristics in intact soil columns in different forest lands and(2) identify the relationship between characteristics of rock fragments and that of the macropores. Intact soil columns that were 100 mm in diameter and 300 mm long were randomly taken from six local forest stony soils in Wuzuolou Forest Station in Miyun, Beijing. Industrial CT was used to scan all soil column samples, and then the scanned images were utilized to obtain the three-dimensional(3 D) images of rock fragments and macropore structures. Next, theparameters of the rock fragments and macropore structure were measured, including the volume, diameter, surface area, and number of rock fragments, as well as the volume, diameter, surface area, length, angle, tortuosity and number of macropores. The results showed that no significant difference was found in soil rock fragments content in the 10-30 cm layer between mixed forest and pure forest, but in the 0-10 cm soil layer, the rock fragments in mixed forest were significantly less than in pure forest. The number density of macropores has significant negative correlation with the number of rock fragments in the 0-10 cm soil layer, whereas this correlation is not significant in 10-20 cm and 20-30 cm soil layers. The volume density of macropore was not correlated with the volume density of rock fragments, and there is no correlation between the density of macropore surface area and the density of rock fragment surface area. Industrial CT scanning combined with image processing technology canprovide a better way to explore 3 D distribution of rock fragments in soil. The content of

关键词： Rock fragment Macropore Forest stone soil Mountain area Industrial Computed Tomography

Bioengineered skin organoids:from development to applications

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Military Medical Research 2024年第3期11卷 449-466页

作者： zi-xuan Hong Shun-Tian Zhu Hao Li Jing-Zhi luo Yu Yang Yang An xi Wang Kai Wang Department of Physiology and Pathophysiology School of Basic Medical SciencesState Key Laboratory of Vascular Homeostasis and RemodelingPeking UniversityBeijing 100191China Department of Hepatopancreatobiliary Surgery the Third Affiliated Hospital of Soochow UniversityChangzhou 213000JiangsuChina Department of Plastic Surgery Peking University Third HospitalBeijing 100191China Clinical Stem Cell Research Center Peking University Third HospitalBeijing 100191China State Key Laboratory of Cardiovascular Disease Fuwai HospitalBeijing 100037China Beijing Key Laboratory of Metabolic Disorder Related Cardiovascular Disease Capital Medical UniversityBeijing 100050China

Signifcant advancements have been made in recent years in the development of highly sophisticated skin *** as three-dimensional(3D)models that mimic human skin,these organoids have evolved into complex structures and are increasingly recognized as efective alternatives to traditional culture models and human skin due to their ability to overcome the limitations of two-dimensional(2D)systems and ethical *** inherent plasticity of skin organoids allows for their construction into physiological and pathological models,enabling the study of skin development and dynamic *** review provides an overview of the pivotal work in the progression from 3D layered epidermis to cyst-like skin organoids with ***,it highlights the latest advancements in organoid construction facilitated by state-of-the-art engineering techniques,such as 3D printing and microfuidic *** review also summarizes and discusses the diverse applications of skin organoids in developmental biology,disease modelling,regenerative medicine,and personalized medicine,while considering their prospects and limitations.

关键词： Skin organoid Organoid generation Skin appendage Tissue engineering Disease modelling Regenerative medicine

Syntheses and Structures of Two Zn-Pyrazole/carboxyl Coordination Frameworks

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Chinese Journal of Structural Chemistry 2021年第10期40卷 1265-1270页

作者： OU YANG Chen-Hao WEI zi-Juan HE Liang GUO Yu-Jun luo Ming-Bu LIN Qi-Pu College of Chemistry Fuzhou UniversityFuzhou 350108China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Two pyrazole-based zinc(Ⅱ) metal-organic frameworks,[Zn_(4)(PDC)_(2)(BDC)(H_(2)O)_(2)]_(n) (compound 1,PDC=1H-pyrazole-3,5-dicarboxylic acid,BDC=benzene-1,4,-dicarboxylic acid) and[Zn_(3)(PDC)_(2)(BPY)_(3)(H_(2)O)_(2)]_(n)(compound 2,BPY=4,4-bipyridine),were synthesized and characterized by x-ray diffraction,elemental analysis,thermogravimetric analysis,infrared and fluorescence *** 1 crystallizes in space group Pna2_(1) with a=14.325(3),b=10.004(2),c=16.454(3)Å,V=2357.8(8)Å^(3),Z=4,M_(r)=821.83,D_(c)=2.298 g·cm^(-3),F(000)=1608,GOOF=1.163,the final R=0.0218 and w R=0.0686 for 5150 observed reflections with I>2σ(I).Compound 2crystallizes in monoclinic space group C2/c with a=17.034(2),b=11.6313(9),c=11.7608(13)Å,V=2034.9(4)Å^(3),Z=2,Mr=1006.91,D_(c)=1.643 g·cm^(-3),F(000)=1020,GOOF=1.084,the final R=0.0320 and wR=0.0768 for 2435 observed reflections with I>2σ(I).

关键词： pyrazole-carboxyl x-ray crystallography metal-organic frameworks luminescence

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Effects of ultrasound-combined microbubbles on hippocampal AchE fibers in rats

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Asian Pacific Journal of Tropical Medicine 2014年第5期7卷 352-357页

作者： zi-Li Gong Chun-Mei luo Sheng-Zheng Wu Hong Ran Jie Zhu Jian Zheng Department of Neurology Xinqiao Hospital Affiliated to Third Military Medical University Department of Orthopaedics Xinqiao Hospital Affiliated to Third Military Medical University Department of Ultrasound Xinqiao Hospital Affiliated to Third Military Medical University Department of Neurology Daping Hospital Affiliated to Third Military Medical University

Objective:To investigate the protective effect of ultrasound-combined microbubbles on hippocampal acetylcholinesterase(AchE) fibers in ***:According to random digits table,60 SD rats were divided into two groups,marrow stromal cells(MSCs) intracranial transplantation group and MSCs intracranial transplantation + ultrasonic microbubbles *** stromal cells were cultivated and isolated in vitro;12 weeks after transplantation,spatial learning and memorizing abilities of rats were assessed by Morris water maze;AchE staining method was used to observe changes in density and appearance of AchE staining positive fibers in hippocampal CA1 ***:There was asignificant increase in spatial learning and memorizing abilities of rats in MSCs intracranial transplantation + ultrasonic microbubbles *** AchE staining suggested an increase in the density of AchE staining positive fibers in MSCs intracranial transplantation group;the fibers were regular,intact and *** of hippocampal AchE positive fibers was negatively correlated with the escape latent period and was positively correlated with percentage of the time needed to cross each platform ***:Better promotion of spatial learning and memorizing abilities of rats in MSCs intracranial transplantation + ultrasonic microbubbles group may be related with the protective effect of ultrasound-combined microbubbles on hippocampal acetylcholine fibers.

关键词： Acetylcholine fiber Morris water maze Forebrain ischemia Marrow stromal cells Forebrain ischemia Ultrasound microbubble

Event vertex and time reconstruction in large-volume liquid scintillator detectors

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Nuclear Science and Techniques 2021年第5期32卷 51-62页

作者： zi-Yuan Li Yu-Mei Zhang Guo-Fu Cao zi-Yan Deng Gui-Hong Huang Wei-Dong Li Tao Lin Liang-Jian Wen Miao Yu Jia-Heng Zou Wu-Ming luo Zheng-Yun You School of Physics Sun Yat-Sen UniversityGuangzhou 510275China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics and Technology Wuhan UniversityWuhan 430072China

Large-volume liquid scintillator detectors with ultra-low background levels have been widely used to study neutrino physics and search for dark *** vertex and event time are not only useful for event selection but also essential for the reconstruction of event *** this study,four event vertex and event time reconstruction algorithms using charge and time information collected by photomultiplier tubes were analyzed *** effects of photomultiplier tube properties were also *** results indicate that the transit time spread is the main effect degrading the vertex reconstruction,while the effect of dark noise is *** addition,when the event is close to the detector boundary,the charge information provides better performance for vertex reconstruction than the time information.

关键词： JUNO Liquid scintillator detector Neutrino experiment Vertex reconstruction Time reconstruction

Microstructure,optical,and photoluminescence properties ofβ-Ga_(2)O_(3)films prepared by pulsed laser deposition under different oxygen partial pressures

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Chinese Physics B 2021年第2期30卷 578-583页

作者： Rui-Rui Cui Jun Zhang zi-Jiang luo xiang Guo Zhao Ding Chao-Yong Deng Power Semiconductor Device Reliability Center of the Ministry of Education Department of Electronic ScienceCollege of Big Data and Information EngineeringGuizhou UniversityGuiyang 550025China College of Computer and Information Engineering Guizhou University of CommerceGuiyang 550014China

Theβ-Ga_(2)O_(3)films are prepared on polished Al_(2)O_(3)(0001)substrates by pulsed laser deposition at different oxygen partial *** influence of oxygen partial pressure on crystal structure,surface morphology,thickness,optical properties,and photoluminescence properties are studied by x-ray diffraction(xRD),atomic force microscope(AFM),scanning electron microscope(SEM),spectrophotometer,and *** results of x-ray diffraction and atomic force microscope indicate that with the decrease of oxygen pressure,the full width at half maximum(FWHM)and grain size *** the increase of oxygen pressure,the thickness of the films first increases and then *** room-temperature UV-visible(UV-Vis)absorption spectra show that the bandgap of theβ-Ga_(2)O_(3)film increases from4.76 e V to 4.91 e V as oxygen pressure *** temperature photoluminescence spectra reveal that the emission band can be divided into four Gaussian bands centered at about 310 nm(~4.0 e V),360 nm(~3.44 e V),445 nm(~2.79 e V),and 467 nm(~2.66 e V),*** addition,the total photoluminescence intensity decreases with oxygen pressure increasing,and it is found that the two UV bands are related to self-trapped holes(STHs)at O1 sites and between two O2-s sites,respectively,and the two blue bands originate from V_(Ga)^(2-)at Ga1 tetrahedral *** photoluminescence mechanism of the films is also *** results will lay a foundation for investigating the Ga_(2)O_(3)film-based electronic devices.

关键词： β-Ga_(2)O_(3) pulsed laser deposition band gap photoluminescence

Quality assurance of postharvest grapes against Botrytis cinerea by terbinafine

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Natural Products and Bioprospecting 2023年第1期13卷 502-513页

作者： Yun Zhao Qiong Jin zi-Jiao Wang xing-Yu Tao xiao-Dong luo State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201People’s Republic of China Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of Education and Yunnan ProvinceYunnan Characteristic Plant Extraction LaboratorySchool of Chemical Science and TechnologyYunnan UniversityKunming 650500People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Worldwide,fruit is an indispensable treasure house of nutrition for human beings,occupying a vital position of human *** fruit storage requires efficient antifungal agents to control Botrytis cinerea,which is a vital postharvest disease affecting fruit and leading to enormous ***,with the enormous abuse of existing antifungal drugs,the problem of drug-resistant fungi is imminent,making the controlling diseases caused by pathogenic fungi even more *** repurposing is an efficient alternative method,we evaluated a well-known antifungal chemical,terbinafine,against the agricultural pathogen,*** in vitro,as a result,terbinafine showed strong anti-fungal ***,the in vivo antifungal activity of terbinafine was evaluated,the results showed that terbinafine could reduce the decay area on *** could disrupt the cell membrane integrity,increase cell membrane permeability,and eventual cell death of *** addition,terbinafine reduced decay incidence,and weight loss and maintained the soluble solids,titratable acidity,ascorbic acid,total phenolic,and malondialdehyde content during the storage period of ***,terbinafine could be an antifungal preservative for postharvest table grapes fresh-keeping.

关键词： Terbinafine Botrytis cinerea Antifungal activity Cell membrane Grape preservation