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Organic Chemistry Frontiers 2022年第6期9卷 1574-1579页

作者： Chuan-Chuan Wang Xin-Lu Wang Qing-Ling Zhang Juntao liu zhi-Wei M zhi-jing liu Ya-jing Chen School of Pharmaceutical Sciences Key Laboratory of Advanced Drug Preparation TechnologiesMinistry of Education of ChinaCo-Innovation Center of Henan Province for New Drug R&D and Preclinical SafetyZhengzhou University100 Science AvenueZhengzhou 450001HenanChina Faculty of Science Livestock Product Quality Inspection InstituteHenan University of Animal Husbandry and EconomyNo.146 Yingcai StreetZhengzhou 450044HenanChina

A novel and efficient[3+2]annulation of 2-substituted aziridines and N-tosyl cyanamides via a dominoregioselective ring-opening/5-exo-dig cyclization procedure has been developed,allowing the directpreparation of N_(2)-unprotected five-membered cyclic guanidines in good to excellent yields under mildconditions without metals and strong ***,the highly biologically interesting urea analoguescould also be conveniently obtained via hydrolysis of the produced guanidines.

关键词： membered protected guanidine

Electrochemical aptasensor for the detection of vascular endothelial growth factor(VEGF) based on DNA-templated Ag/Pt bimetallic nanoclusters

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Chinese Chemical Letters 2016年第6期27卷 920-926页

作者： Xian-Ming Fu zhi-jing liu Shu-Xian Cai Yan-Ping Zhao Dong-zhi Wu Chun-Yan Li jing-Hua Chen College of Pharmacy and Medical Technology Putian University Department of Pharmaceutical Analysis the Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian ProvinceThe School of Pharmacy Fujian Medical University Department of Basic Chemistry The School of Pharmacy Fujian Medical University

In this paper, the DNA-templated Ag/Pt bimetallic nanoclusters were successfully synthesized using an optimized synthetic scheme. The obtained DNA-Ag/Pt NCs have an ultrasmall particle size and excellent distribution. The DNA-Ag/Pt NCs show intrinsic peroxidase-mimicking activity and can effectively catalyze the H2O2-mediated oxidation of a substrate, 3,30,5,50-tetramethylbenzidine（TMB）, to produce a blue colored product. Based on this specific property, we employed the aptamer of VEGF to design a label-free electrochemical biosensor for VEGF detection. Under the optimized experimental conditions, a linear range from 6.0 pmol/L to 20 pmol/L was obtained with a detection limit of 4.6 pmol/L. The proposed biosensor demonstrated its high specificity for VEGF and could directly detect the VEGF concentration in human serum samples of breast cancer patients with satisfactory results. This novel electrochemical aptasensor was simple and convenient to use and was cost-effective and label-free in design, and would hold potential applications in medical diagnosis and treatment.

关键词： Vascular endothelial growth factor(VEGF) DNA-templated Ag/Pt bimetallic nanoclusters Enzyme mimics Aptamer Electrochemical aptasensor Protein detection

Research on Full Space Transient Electro-magnetism Technique for Detecting Aqueous Structures in Coal Mines

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Journal of China University of Mining and Technology 2007年第1期17卷 58-62页

作者： YU jing-cun liu zhi-xin TANG Jin-yun School of Mineral Resources and Earth Science China Universi~.＂ of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Based on the transmitting theory of "smoke ring effect", the transient electromagnetism technique was used in coal mines to detect abnormal areas of aquiferous structures in both roofs and floors of coal seams and in front of excavated roadways. Survey devices, working methods and techniques as well as data processing and interpretation are discussed systematically. In addition, the direction of mini-wireframe emission electromagnetic wave of the full space transient electromagnetism technique was verified by an underground borehole for water detection and drainage. The result indicates that this technique can detect both horizontal and vertical development rules of abnormal water bodies to a certain depth below the floor of coal seams and can also detect the abnormal, low resistance water bodies within a certain distance of roofs. Furthermore, it can detect such abnormal bodies in ahead of the excavated roadway front. Limited by the underground environment, the full space transient electromagnetism technique can detect to a depth of only 120 m or so.

关键词： water eruption structure water hazard in coal mines detection technique full space transient electromagnetism

Magnetic emission intensity enhancement for amorphous alloys by constructing a multi-phase structure withα-Fe nanocrystals

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Nano Research 2024年第7期17卷 6630-6637页

作者： Ke liu zhi Qin Jie Shen zhi Cheng Shiyue You Liang Ma jing Zhou Wen Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park Wuhan University of TechnologySanya 572024China Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyang 441000China

The perturbation in the magnetic field generated by the rotation or oscillation of magnetic domains in magnetic materials can emit low-frequency electromagnetic waves,which are expected to be used in low-frequency ***,the magnetic emission intensity,defined by the perturbation ability,of current commercially applied amorphous alloys,such as Metglas,cannot meet the application requirements for low-frequency antennas due to the domain motion energy ***,a multi-phase Metglas amorphous alloy was constructed by incorporatingα-Fe nanocrystals using rapid annealing to manipulate the domain *** was found that 3.89 times higher magnetic emission intensity is obtained compared to the pristine due to the synergism of the deformation and displacement ***,the low-frequency magnetic emission performance verification was carried out by preparing magnetoelectric composites as the antenna vibrator by assembling the alloy and macro piezoelectric fiber composites(MFC).Enhancements of magnetic emission intensity are found at 93.3%and 49.2%at the first and second harmonic frequencies compared with the unmodified alloy ***,the approach leads to the development of high-performance communication with a novel standard for evaluation.

关键词： multi-phase amorphous alloys magnetic emission intensity enhancing mechanism magnetic domain pinning theory Jiles-Atherton model analysis

Akt-centered amplification loop plays a critical role in vascular endothelial growth factor/stromal cell-derived factor 1-αcross-talk and cardioprotection

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Chinese Medical Journal 2011年第22期124卷 3800-3805页

作者： GUO Wen-yi ZHANG Dian-xin LI Wei-jie ZHAO zhi-jing liu Bing WANG Hai-chang LI Fei Department of Cardiology Xijing Hospital Fourth Military Medical University Xi＇an Shaanxi 710032 China

Background Vascular endothelial growth factor （VEGF） is one of major mediators of angiogenesis and survival factor in some tissue, however, its direct effects on cardiomyocytes remain poorly understood. Methods Rat neonatal ventricular myocytes were cultured in vitro. Akt phosphorylation was measured by Western blotting; the expression of stromal cell-derived factor α（SDF-1α）/CXCR4 axis was evaluated by real-time PCR and Western blotting. LY294002 and AMD3100 were used to interfere with the signaling of VEGF and SDF-1α/CXCR4 axis. Cardiac myocytes viability and injury were evaluated by trypan blue staining and lactate dehydrogenase （LDH） release. Results Treatment of neonatal rat ventricular myocytes with VEGF induced phosphorylation of Akt in a dose and FIk-1 dependent manner. VEGF attenuated H202 induced cardiac myocyte death. The phosphoinositol-3-kinase （PI3K） inhibitor, LY294002 and FIk-1 antibody abolished the beneficial effects of VEGF on H202 induced cell death. In the mean time SDF-1α-CXCR4 axis was up-regulated by VEGF through PI3K-Akt signaling and contributed to the protective effects of VEGF on H202 induced cell death. Interestingly, SDF-1α also promoted production of VEGF in cultured cardiac myocytes and LY294002 reversed the up-reguLation of VEGF induced by SDF-1α. Conclusion VEGF has direct protective effects on cardiomyocytes; a crosstalk between VEGF and SDF-1α through PI3K-Akt serves a survival role in cardiomvocvtes in vitro.

关键词： vascular endothelial growth factor cardiomyocyte, stromal cell-derived factor a survival PI3K-Akt

Microphase Separation of Semiflexible Ring Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第2期42卷 267-276,I0011页

作者： Dan-Yan Qin Sheng-Da Zhao zhi-Xin liu jing Zhang Xing-Hua Zhang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the difficult problem of solving the conformation statistics of complex polymers, this study presents a novel and concise conformation statistics theoretical approach based on Monte Carlo and Neural Network method. This method offers a new research idea for investigating the conformation statistics of complex polymers, characterized by its simplicity and practicality. It can be applied to more complex topological structure, more higher degree of freedom polymer systems with higher dimensions, theory research on dynamic self-consistent field theory and polymer field theory, as well as the analysis of scattering experimental data. The conformation statistics of complex polymers determine the structure and response properties of the system. Using the new method proposed in this study, taking the semiflexible ring diblock copolymer as an example, Monte Carlo simulation is used to sample this ring conformation to construct the dataset of polymer. The structure factor describing conformation statistics are expressed as continuous functions of structure parameters by neural network supervised learning. This is the innovation of this work. As an application, the structure factors represented by neural networks were introduced into the random phase approximation theory to study the microphase separation of semiflexible ring diblock copolymers. The influence of the ring's topological properties on the phase transition behavior was pointed out.

关键词： Ring copolymer Diblock copolymers Semiflexible The order-disorder transition

Graphdiyne(C_(n)H_(2n-2))as an"electron transfer bridge"boosting photocatalytic hydrogen evolution over Zn_(0.5)Co_(0.5)S/MoS_(2)S-scheme heterojunction

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Rare Metals 2024年第5期43卷 1999-2014页

作者： Mei Li jing-zhi Wang zhi-Liang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China School of Chemistry and Chemical Engineering Ningxia Key Laboratory of Solar Chemical Conversion TechnologyKey Laboratory for Chemical Engineering and TechnologyState Ethnic Affairs CommissionNorth Minzu UniversityYinchuan 750021China

In the process of photocatalytic water cracking,the migration rate and utilization rate of photogenerated charges determine the hydrogen evolution performance of the *** this paper,a carbon isotope superconducting material graphdiyne(GDY)is prepared by mechanical ball milling and introduced into the S-scheme heterojunction Zn_(0.5)Co_(0.5)S/MoS_(2)inorganic *** terms of hydrogen evolution kinetics,GDY acts as an electron bridge,not only accelerating the migration of photogenerated carriers but also improving the utilization of photogenerated ***,the large twodimensional layer provides more loading and anchoring points for Zn_(0.5)Co_(0.5)S/MoS_(2),which increases the number of active *** ternary composite catalyst 20%GDY/Zn_(0.5)Co_(0.5)S/MoS_(2)(20-GCSM)generates 69.94μmol of hydrogen(5 h)in triethanolamine *** is 2.97 and1.80 times higher than Zn_(0.5)Co_(0.5)S and Zn_(0.5)Co_(0.5)S/MoS_(2),*** the cyclic experiment,it still has stable hydrogen evolution performance after standing for24 h(under dark conditions).In addition,the potential mechanism of photocatalytic hydrogen evolution is demonstrated through in-situ X-ray photoelectron *** work provides a reference for further research in the field of introducing carbon materials into photocatalytic systems and improving the utilization of photogenerated charges.

关键词： Graphdiyne S-scheme heterojunction Electron transfer bridge Hydrogen production

Secoemestrin C Ameliorates Psoriasis-like Skin Inflammation in Mice by Suppressing the TNF-α/NF-κB Signaling Pathway

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Current Medical Science 2024年第1期44卷 232-240页

作者： zhi-bin ZHU Meng-jie liu jing WANG Zhou SHU Jie CAO Department of Stomatology Chengdu Seventh People's HospitalChengdu 610044China Department of Pharmacy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective Secoemestrin C(SC),an epitetrathiodioxopiperazine isolated from Aspergillus nidulans,has been previously reported to have immunomodulatory and hepatoprotective effects against acute autoimmune ***,the effect of SC on regulating the inflammation and its underlying mechanisms in the pathogenesis of psoriasis remain *** study aimed to evaluate the effects of SC on inflammatory dermatosis both in vitro and in *** In vitro,HaCaT cells were induced with tumor necrosis factor-alpha(TNF-α,10 ng/mL)to establish an inflammatory injury model,and the expression of nuclear transcription factor-κB(NF-κB)pathway components was measured using qRT-PCR and Western *** in vivo mouse model of imiquimod(IMQ)-induced psoriasis-like skin inflammation was used to evaluate the effectiveness of SC in alleviating *** SC significantly blocked the activation of NF-κB signaling in TNF-α-stimulated HaCaT *** addition,systemic and local administration of SC improved psoriatic dermatitis in the IMQ-induced mouse *** reduced skin scale and significantly inhibited the secretion of inflammatory factors in skin *** The protective effect of SC against psoriatic-associated inflammation reveals its potential therapeutic value for treating psoriasis.

关键词： secoemestrin C(SC) psoriasis tumor necrosis factor-alpha(TNF-α) nuclear transcription factor-kB(NF-kB) inflammation

Calcitonin gene-related peptide inhibits neuronal apoptosis in heatstroke rats via PKA/p-CREB pathway

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Chinese Journal of Traumatology 2024年第1期27卷 18-26页

作者： Jie Zhu Ya-Hong Chen jing-jing Ji Cheng-Xiang Lu zhi-Feng liu Department of Pediatric General Hospital of Southern Theater Command of PLAGuangzhou510010China Department of Medical Intensive Care Unit General Hospital of Southern Theater Command of PLAGuangzhou510010China Department of Intensive Care Unit Zhongshan Hospital Xiamen UniversityXiamenFujian province361004China

Purpose:The incidence of heatstroke(HS)is not particularly high;however,once it occurs,the consequences are *** is reported that calcitonin gene-related peptide(CGRP)is protective against brain injury in HS rats,but detailed molecular mechanisms need to be further *** this study,we further explored whether CGRP inhibited neuronal apoptosis in HS rats via protein kinase A(PKA)/p-cAMP response element-binding protein(p-CREB)***:We established a HS rat model in a pre-warmed artificial climate chamber with a temperature of(35.5±0.5)℃and a relative humidity of 60%±5%.Heatstress was stopped once core body temperature reaches above 41℃.A total of 25 rats were randomly divided into 5 groups with 5 animals each:control group,HS group,HS+CGRP group,HS+CGRP antagonist(CGRP8-37)group,and HS+CGRP+PKA/p-CREB pathway blocker(H89)group.A bolus injection of CGRP was administered to each rat in HS+CGRP group,CGRP8-37(antagonist of CGRP)in HS+CGRP8-37 group,and CGRP with H89 in HS+CGRP+H89 *** were recorded and the serum concentration of S100B,neuron-specific enolase(NSE),neuron apoptosis,activated caspase-3 and CGRP expression,as well as pathological morphology of brain tissue were detected at 2 h,6 h,and 24 h after HSin *** expression of PKA,p-CREB,and Bcl-2 in rat neurons were also detected at 2 h after HSin *** CGRP,CGRP8-37,or H89 were used to determine whether CGRP plays a protective role in brain injury via PKA/p-CREB *** unpairedt-test was used between the 2 samples,and the mean±SD was used for multiple ***-tailedp<0.05 was considered statistically ***:Electroencephalogram showed significant alteration ofθ(54.50±11.51vs.31.30±8.71,F=6.790,p=0.005)andαwave(16.60±3.21vs.35.40±11.28,F=4.549,p=0.020)in HS group compared to the control group 2 h after *** results of triphosphate gap terminal labeling(TUNEL)showed that the neuronal apoptosis of HS rats was increased in the c

关键词： Heatstroke Calcitonin gene-related peptide Brain injury Apoptosis

Carbon cathode with heteroatom doping and ultrahigh surface area enabling enhanced capacitive behavior for potassium-ion hybrid capacitors

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Rare Metals 2024年第5期43卷 2136-2149页

作者： Yan Xiong Ya-Fei Zhang Chun-liu Zhu Lei Yang Huan-Yu Liang jing Shi jing-Wei Chen Wei-QianTian Shuai liu zhi Li jing-Yi Wu Huan-Lei Wang School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 2V4Canada

Potassium-ion hybrid capacitors(PIHCs)are widely regarded as highly promising energy storage devices,due to their exceptional energy density,impressive power density,and abundant potassium ***,restricted by the inherent capacitive storage mechanism,the carbon cathodes possess a much lower specific capacity than battery-type ***,designing high-performance carbon cathodes is extremely urgent for the development of ***,N,O codoped porous carbon(NOPC)was fabricated through the NaCl hard template method and combined KOH/melamine chemical activation technique,displaying the characteristics of abundant N/O content(4.7 at%/16.9 at%),ultrahigh specific surface area(3092 m^(2)g^(-1))and hierarchical pore *** designed NOPC cathode delivers a high specific capacity(164.4 mAh.g^(-1)at 0.05 A.g^(-1))and superior cyclability(95.1%retention ratio at 2 A·g^(-1)over 2500 cycles).Notably,the adjustable ratio of micropores to mesopores facilitates the achievement of the optimal bal-ance between capacity and rate ***,the pseudocapacitance can be further augmented through the incorporation of N/O functional *** expected,the graphite//NOPC based PIHC possesses a high energy density of 113 Wh·kg-at 747 W·kg^(-1)and excellent capacity retention of 84.4% fter 400 cycles at 1.0 A·g^(-1).This work introduces a novel strategy for designing carbon cathodes that enhances the electrochemical performance of PIHCs.

关键词： Template method N/O co-doping High specific surface area Carbon cathode Potassium-ion capacitors