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Neural Regeneration Research 2017年第8期12卷 1329-1337页

作者： Zhi-yuan Su Qing Ye Xian-bao Liu Yu-zhong Chen Hong Zhan shi-yuan xu Department of Anesthesia The Third Affiliated Hospital of Guangzhou Medical University Department of Anesthesia Zhujiang Hospital of Southern Medical University

Dexmedetomidine has significant neuroprotective effects. However, whether its protective effects can reduce neurotoxicity caused by isoflurane in fetal brain during the second trimester of pregnancy remains unclear. In this study, timed-pregnancy rats at gestational day 14 spontaneously inhaled 1.5% isoflurane for 4 hours, and were intraperitoneally injected with dexmedetomidine at dosages of 5, 10, 20, and 20 μg/kg 15 minutes before inhalation and after inhalation for 2 hours. Our results demonstrate that 4 hours after inhaling isoflurane, 20 μg/kg dexmedetomidine visibly mitigated isoflurane-induced neuronal apoptosis, reversed downregulation of brain-derived neurotrophic factor expression, and lessened decreased spatial learning and memory ability in adulthood in the fetal rats. Altogether, these findings indicate that dexmedetomidine can reduce neurodegeneration induced by isoflurane in fetal rats during the second trimester of pregnancy. Further, brain-derived neurotrophic factor participates in this process.

关键词： nerve regeneration dexmedetornidine isoflurane fetal rat apoptosis brain-derived neurotrophic factor behavior neuroprotection neurodegeneration neural regeneration

Supramolecular Radical Switches Regulated by Host-Guest Chemistry

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Chinese Journal of Chemistry 2022年第21期40卷 2568-2574页

作者： Yu-yuan Ye Zi-Xin Wang shi-yuan xu Xiao-Wei Lin Jie Luo Wen-Zhen Li Xiao-Qiang Wang Schoolof Chemistry and Chemical Engineering Wuhan Universityof Science and TechnologyWuhanHubei 430081China

Water-soluble thermal initiators are important radical sources to be applied in various ***,the uncontrolled radical generation from the high sensitivity of initiators may cause disadvantages in the ***,we present a series of supramolecular radical switches regulated by the host-guest chemistry between initiators and cucurbit[8]uril(CB[8]).Thermal initiators(VA-044,VA-056,VA-057)can be spontaneously encapsulated into the cavity of CB[8]to“turn off”their radical-generation *** activity will instantaneously“turn on”in the presence of other competitors such as 1-adamantylamine(ADA).Further,we demonstrated the free radical polymerization of N-isopropylacrylamide using initiators,inhibiting its activity by binding with CB[8]and initiating reaction by adding *** novel supramolecular radical switches provide a facile strategy to control the generation of free radicals in a“plug-and-play”manner,which may arouse research interests in polymerization,catalysis,and the biomedical field.

关键词： Supramolecular chemistry Cucurbituril Azo compound Radicals Radical switch

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： xu Pan Wei Jiang Chuan Yue shi-Jun Lei Yu-Xin Cui Qiang yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Mediated protective effect of electroacupuncture pretreatment by miR-214 on myocardial ischemia/reperfusion injury

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Journal of Geriatric Cardiology 2014年第4期11卷 303-310页

作者： Pei-Yu LIU Yi TIAN shi-yuan xu Department of Anesthesiology ZhuJiang Hospital of Southern Medicine University Guangzhou 510282 Guangdong Province China Department of Anesthesiology Hainan Provincial Corps Hospital of Chinese People's Armed Police Forces Haikou 570203 Hainan Province China Department of Anesthesiology Haikou People's Hospital Haikou 570203 Hainan Province China

Background Electroacupuncture pretreatment plays a protective role in myocardial ischemia/reperfusion （I/R） injury and microRNAs （miRNAs） could act on various facets of cardiac function. However, the role of miRNAs in the cardioprotection by electroacupuncture pre-treatment on myocardial I/R injury remains unknown. The purpose of the study was to examine whether miR-214 was involved in cardio-protection by electroacupuncture. Methods Using rat myocardial I/R model, we examined the role of electroacupuncture pretreatment in myocardial I/R injury and analyzed the changes in the expression of miR-214. In addition, I/R was simulated in vitro by performing oxy-gen-glucose deprivation （OGD） on H9c2 cell cultures, and the effect of electroacupuncture pretreatment on I/R injury as well as expressional level of miR-214 were examined in vitro. Furthermore, the miR-214 mimic was transfected into OGD-treated H9c2 cells, we analyzed the cell apoptosis, lactate dehydrogenase （LDH） and creatine kinase （CK） activities, intracellular free Ca2＋concentration （[Ca2＋]i） as well as the relative protein levels of sodium/calcium exchanger 1（NCX1）, BCL2-like 11 （BIM）, calmodulin-dependent protein kinase IIδ（CaMKIIδ） and Cyclophilin D （CypD）. Results The in vivo results revealed that compared with the I/R group, the electroacupuncture pretreatment group showed significant decreased myocardial infarct size, as well as the increased indices of the cardiac function, including heart rate, mean arterial pressure, left ventricular systolic pressure and maximal rate for left ventricular pressure rising and declining （±dp/dt max）. In addition, electroacupuncture pretreatment could inhibit the elevation of LDH and CK activities induced by I/R injury. The quantitative PCR （qPCR） results demonstrated electroacupuncture pretreatment could provide cardioprotection against myocardial I/R injury in rats with miR-214 up-regulation. In the meanwhile, in vitro, electroacupuncture pretreatment protected H9c2 c

关键词： I/R injury miR-214 Electroacupuncture Protective effect

On Isodual Double Toeplitz Codes

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Journal of Systems Science & Complexity 2024年第5期37卷 2196-2206页

作者： shi Minjia xu Li SOLÉ Patrick Key Laboratory of Intelligent Computing and Signal Processing Ministry of EducationSchool of Mathematical SciencesAnhui UniversityHefei 230601China State Key Laboratory of Information Security Institute of Information EngineeringChinese Academy of SciencesBeijing 100093China CNRS University of Aix MarseilleCentrale MarseilleI2MMarseille 13284France

Double Toeplitz(shortly DT)codes are introduced here as a generalization of double circulant *** authors show that such a code is isodual,hence formally self-dual(FSD).FSD codes form a far-reaching generalization of self-dual codes,the most important class of codes of rate ***-dual DT codes are characterized as double circulant or double ***,even binary DT codes are characterized as double *** examples obtained by exhaustive search show that the codes constructed have best-known minimum distance,up to one unit,amongst formally self-dual codes,and sometimes improve on the known *** q=2,the authors find four improvements on the best-known values of the minimum distance of FSD *** F4 an explicit construction of DT codes,based on quadratic residues in a prime field,performs equally *** authors show that DT codes are asymptotically good over ***,the authors construct DT codes arbitrarily close to the asymptotic Varshamov-Gilbert bound for codes of rate one half.

关键词： Double circulant codes double Toeplitz codes isodual codes formally self-dual codes

Performance evaluation of the effect of humic acid on Anammox granular sludge:Apparent morphology,nitrogen removal and microbial community

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Journal of Environmental Sciences 2024年第10期144卷 148-158页

作者： Wenhui Huang Peiling xu Xiang Li Yong Huang Hao Sun Wei Li Mao Zhang Miao shi Yan yuan School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Suzhou Hongyu Environmental Technology Company Limited by Shares Suzhou 215011China Suzhou Tianjun Environmental Technology Limited Company Suzhou 215011China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou 215009China

Humic acid(HA)is a typical refractory organicmatter,so it is of great significance to investigate its effect on the performance of Anammox granular *** the dosage ofHA≤50 mg/L,HA promotes the total nitrogen removal rate(NRR)to 1.45 kg/(m^(3)·day).When HA was between 50 and 100 mg/L,the NRR of Anammox was *** this time,the adsorption of HA causes the sludge to gradually turn fromred to brown,but the activities of heme and enzymes showed that its capacitywas not *** HA levels reached 250 mg/L,the NRR dropped to 0.11 kg/(m3·day).Moderate HA levels promoted the release of extracellular polymeric substance(EPS),but excessive HA levels lead to a decrease in EPS *** inhibited Anammox activity,which indirectly hindered the transmission of substrate and accumulated substrate *** HA promoted the increase of heterotrophicmicrobial abundance in Anammox system,the microbial diversity decreased *** the increase of HA concentration,the abundance of Candidatus_Brocadia,the main functional microorganism of Anammox system,decreased gradually,while the abundance of Candidatus_Kuenenia increased gradually.

关键词： Anammox Landfill leachate Humic acid Heme Microbial community Enzyme activity

Tough Semi-interpenetrating Polyvinylpyrrolidone/Polyacrylamide Hydrogels Enabled by Bioinspired Hydrogen-bonding Induced Phase Separation

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Chinese Journal of Polymer Science 2024年第5期42卷 591-603,I0006页

作者： Qiong-Jun xu Zhao-Yang yuan Chang-Cheng Wang Hao Liang Yu shi Hai-Tao Wu Hu xu Jing Zheng Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China

Semi-interpenetrating(semi-IPN)hydrogels formed by the continuous interpenetration of cross-linked polymer network and linear non-crosslinked polymer with multifunctionality are widely used in biomedical and other ***,the negative impact of linear polymer on the homogeneity of the cross-linked network often leads to a decrease in the mechanical properties of semi-IPN hydrogels and severely limits their ***,a bioinspired hydrogen-bonding induced phase separation strategy is presented to construct the tough semi-IPN polyvinylpyrrolidone/polyacrylamide hydrogels(named PVP/PAM hydrogels),including the linear polymer polyvinylpyrrolidone(PVP)and cross-linked polyacrylamide(PAM)*** resultant PVPx/PAM hydrogels exhibit unique phase separation induced by the hydrogen bonding between PVP and PAM and affected by the amount of substance of ***,the phase separation of PVPx/PAM hydrogels results in excellent mechanical properties with a strain of 2590%,tensile strength of 0.28 MPa and toughness of 2.17 MJ/m^(3).More importantly,the hydrogen bonding between PVP and PAM firstly disrupts to dissipate energy under external forces,so the PVPx/PAM hydrogels exhibit good self-recovery properties and outperform chemically cross-linked PAM hydrogels in impact resistance and damping *** is believed that the PVPx/PAM hydrogels with hydrogen-bonding induced phase separation possess more potential application prospects.

关键词： Tough Semi-interpenetrating networks Polyvinylpyrrolidone/polyacrylamide Hydrogels Phase separation

The Probability Density Function Related to Shallow Cumulus Entrainment Rate and Its Influencing Factors in a Large-Eddy Simulation

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Advances in Atmospheric Sciences 2024年第1期41卷 173-187页

作者： Lei ZHU Chunsong LU Xiaoqi xu Xin HE Junjun LI shi LUO yuan WANG Fan WANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)and Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration Nanjing University of Information Science and TechnologyNanjing 210044China Nanjing Joint Institute for Atmospheric Sciences Nanjing 210019China College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China Department of Geography Hong Kong Baptist UniversityHong Kong SAR 999077China

The process of entrainment-mixing between cumulus clouds and the ambient air is important for the development of cumulus *** obtaining the entrainment rate(λ)is particularly important for its parameterization within the overall cumulus parameterization *** this study,an improved bulk-plume method is proposed by solving the equations of two conserved variables simultaneously to calculateλof cumulus clouds in a large-eddy *** results demonstrate that the improved bulk-plume method is more reliable than the traditional bulk-plume method,becauseλ,as calculated from the improved method,falls within the range ofλvalues obtained from the traditional method using different conserved *** probability density functions ofλfor all data,different times,and different heights can be well-fitted by a log-normal distribution,which supports the assumed stochastic entrainment process in previous *** analysis demonstrate that the relationship betweenλand the vertical velocity is better than other thermodynamic/dynamical properties;thus,the vertical velocity is recommended as the primary influencing factor for the parameterization ofλin the *** results of this study enhance the theoretical understanding ofλand its influencing factors and shed new light on the development ofλparameterization.

关键词： large-eddy simulation cumulus clouds entrainment rate probability density functions spatial and temporal distribution

Production induced fracture closure of deep shale gas well under thermo-hydro-mechanical conditions

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Petroleum Science 2024年第3期21卷 1796-1813页

作者： shi-Ming Wei Yang Xia Yan Jin xu-Yang Guo Jing-Yu Zi Kai-xuan Qiu Si-yuan Chen College of Science China University of Petroleum(Beijing)Beijing102249China CNOOC Research Institute Ltd Beijing100028China The University of Hong Kong Hong Kong999077China

Deep shale gas reservoirs have geological characteristics of high temperature,high pressure,high stress,and inferior ability to pass through *** multi-stage fractured horizontal well is the key to exploiting the deep shale gas ***,during the production process,the effectiveness of the hydraulic fracture network decreases with the closure of fractures,which accelerates the decline of shale gas *** this paper,we addressed the problems of unclear fracture closure mechanisms and low accuracy of shale gas production prediction during deep shale gas *** we established the fluid—solid—heat coupled model coupling the deformation and fluid flow among the fracture surface,proppant and the shale *** the fluid—solid—heat coupled model was applied to the fracture network,it was well solved by our numerical method named discontinuous discrete fracture *** with the conventional discrete fracture method,the discontinuous discrete fracture method can describe the three-dimensional morphology of the fracture while considering the effect of the change of fracture surface permeation coefficient on the coupled fracture—matrix flow and describing the displacement discontinuity across the *** simulations revealed that the degree of fracture closure increases as the production time proceeds,and the degree of closure of the secondary fractures is higher than that of the primary *** creep and proppant embedment both increase the degree of fracture *** reduction in fracture surface permeability due to proppant embedment reduces the rate of fluid transfer between matrix and fracture,which has often been overlooked in the ***,it significantly impacts shale gas production,with calculations showing a 24.7%cumulative three-year yield *** study is helpful to understand the mechanism of hydraulic fracture ***,it provides the theoretical guidance for maintaining the long

关键词： Shalegas Fracture closure Fluid-solid-heat coupling Discontinuous discrete fracture

Theory and test of underground explosions:Coupling rule between cratering and ground shock

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Underground Space 2024年第4期17卷 146-160页

作者： Wei Guo Jie Li Benjun shi Tianhan xu Xiaohui xu Gan Li Jie shi State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact Army Engineering University of PLANanjing 210007China

Calculating the parameters of the ground shock induced by an underground explosion is a complex energy coupling *** is difficult to establish a unified ground shock coupling law from limited test *** paper summarizes the research results obtained at home and abroad and systematically analyzes the coupling mechanism of craters formed by an underground explosion and the ground *** differences between the concepts of"closed-explosion critical depth"and"equivalent closed-explosion critical depth"are clearly *** spreading of the ground shock energy is attributed to the explosive expansion of the air cavity,revealing a linear relationship between the volume of the cavity region(or the volume of the crack region)and the ground shock energy associated with the underground *** proportionality factor is related to the mechanical properties of the medium and is independent of the magnitude of the explosion *** on this,a theoretical calculation formula and conversion method for the ground shock coupling coefficient were *** tests were conducted in clay and Plexiglass under varying burial *** test results were consistent with the theoretically calculated *** study provides a theoretical basis for the design of explosion-resistant structures in underground engineering.

关键词： Underground explosion Ground shock coupling Coupling coefficient Equivalent closed explosion Experimental study