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Hypothermia selectively protects the anterior forebrain mesocircuit during global cerebral ischemia

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Neural Regeneration Research 2022年第7期17卷 1512-1517页

作者： Xiao-Hua Wang Wei jiang Si-Yuan Zhang Bin-Bin Nie Yi Zheng feng Yan Jian-Feng Lei Tian-Long Wang Department of Anesthesiology Xuanwu HospitalCapital Medical UniversityBeijingChina National Clinical Research Center for Geriatric Disorders BeijingChina Department of Anesthesiology Third Medical Center of People’s Liberation Army General HospitalBeijingChina Daxing Hospital Affiliated to Capital Medical University BeijingChina Beijing Engineering Research Center of Radiographic Techniques and Equipment Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijingChina Neuroprotection Research Laboratory Departments of Radiology and NeurologyMassachusetts General Hospital and Harvard Medical SchoolCharlestownMAUSA Cerebrovascular Research Center Xuanwu HospitalCapital Medical UniversityBeijingChina

Hypothermia is an important protective strategy against global cerebral ischemia following cardiac arrest.However,the mechanisms of hypothermia underlying the changes in different regions and connections of the brain have not been fully elucidated.This study aims to identify the metabolic nodes and connection integrity of specific brain regions in rats with global cerebral ischemia that are most affected by hypothermia treatment.18F-fluorodeoxyglucose positron emission tomography was used to quantitatively determine glucose metabolism in different brain regions in a rat model of global cerebral ischemia established at 31–33℃.Diffusion tensor imaging was also used to reconstruct and explore the brain connections involved.The results showed that,compared with the model rats established at 37–37.5℃,the rat models of global cerebral ischemia established at 31–33℃had smaller hypometabolic regions in the thalamus and primary sensory areas and sustained no obvious thalamic injury.Hypothermia selectively preserved the integrity of the anterior forebrain mesocircuit,exhibiting protective effects on the brain during the global cerebral ischemia.The study was approved by the Institutional Animal Care and Use Committee at Capital Medical University(approval No.XW-AD318-97-019)on December 15,2019.

关键词： anterior forebrain mesocircuit cardiac arrest corpus callosum global cerebral ischemia hypometabolic areas hypothermia magnetic resonance imaging positron emission tomography prefrontal cortex rats thalamus

Modification of SDOF model for reinforced concrete beams under close-in explosion

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Defence Technology（防务技术） 2023年第2期20卷 162-186页

作者： Wei Wei Yu-lei Zhang jian-jun Su Yan Liu feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Xi'an Modern Chemistry Research Institute Xi'an710065China

In this paper,a modified single-degree-of-freedom(SDOF)model of reinforced concrete(RC)beams under close-in explosion is proposed by developing the specific impulse equivalent method and flexural resistance calculation method.The equivalent uniform specific impulse was obtained based on the local conservation of momentum and global conservation of kinetic energy.Additionally,the influence of load uniformity,boundary condition and complex material behaviors(e.***.strain rate effect,hardening/softening and hoop-confined effect)was considered in the resistance calculation process by establishing a novel relationship between external force,bending moment,curvature and deflection successively.The accuracy of the proposed model was verified by carrying out field explosion tests on four RC beams with the scaled distances of 0.5 m/kg~(1/3)and 0.75 m/kg~(1/3).The test data in other literatures were also used for validation.As a result,the equivalent load implies that the blast load near the mid-span of beams would contribute more to the maximum displacement,which was also observed in the tests.Moreover,both the resistance model and test results declare that when the blast load becomes more concentrated,the ultimate resistance would become lower,and the compressive concrete would be more prone to softening and crushing.Finally,based on the modified SDOF model,the calculated maximum displacements agreed well with the test data in this paper and other literatures.This work fully proves the rationality of the modified SDOF method,which will contribute to a more accurate damage assessment of RC structures under close-in explosion.

关键词： SDOF model Close-in explosion Specific impulse equivalent method Flexural resistance

Field measurement and evaluation of vibration in different areas of a metro depot

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 529-542页

作者： feng Qingsong Zhang Yunlai jiang jian Wang Ziyu lei Xiaoyan Zhang Ling Engineering Research Center of Railway Environment Vibration and Noise Ministry of EducationEast China Jiaotong UniversityNanchang 330013China Institute of Sound and Vibration Research University of SouthamptonHighfieldSouthamptonHampshire SO171BJUK

This paper presents a study of the characteristics of a railway vibration at three key sections containing different track structures in a metro depot.The results show that the vertical and horizontal vibration acceleration levels are proportional to train speed.The Z-weighted vertical acceleration levels obtained showed that the vibration source strengths at the ballast foot of the testing line and the throat area were very close.The vibration attenuation at the repair line was larger than that of the testing line.In the throat area,the peak frequency of vibration obtained at the ballast foot(2.5 m)could be shifted to a lower frequency band by using polyurethane sleepers instead of standard concrete sleepers.Polyurethane sleepers can help to reduce vertical vibration in a frequency band of 0-10 Hz.The vibration levels would satisfy the limits given in the ISO2631-2-2003(2013)for any location more than 5 m away from the source at the testing line and 2.5 m away from the source at the repair line and throat area.

关键词： field measurement metro depot peak frequency vibration acceleration environmental impacts

Migration of harmful elements in municipal sludge under hightemperature oxidation conditions

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Journal of Iron and Steel Research(International) 2023年第9期30卷 1701-1713页

作者： Xiao-dong Ping Hai-feng Wang feng Wang Xin-yu Wan Zhi-wei An jian-lei Pan State Key Laboratory of Advanced Steel Processes and Products Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China Department of Science and Technology Development China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China Production and Equipment Department Chengde Jianlong Special Steel Co.Ltd.Chengde 067200HebeiChina Technology Department Chengde Jianlong Special Steel Co.Ltd.Chengde 067200HebeiChina

Municipal sludge is produced in large amounts and is difficult to treat.Incineration is the most direct and thorough treatment method.In order to study the feasibility of sintering for municipal sludge treatment,the municipal sludge reforming process was studied under high-temperature oxidation conditions.The results showed that the sludge reforming process could be divided into four stages:the precipitation and evaporation of adsorbed water,the precipitation and combustion of the volatile,the combustion of the residual volatile and solid carbon,and the decomposition of salts and the melting of sludge.An increase in the heating rate resulted in more intense sludge combustion and improved the sludge reaction capacity and combustion performance.After burning at 1300℃,Si,Ca,Mg,Al,K,Na,and Cu formed new phases and entered the slag.75%of P remained in the slag.80%of the S formed SO_(2) and entered the flue gas.Cl formed gaseous chlorides like HCl upon combustion and entered the flue gas.As sintering is a feasible method for treating municipal sludge,care must be taken to limit the amount of P that ends up in the ore.

关键词： Municipal sludge Oxidizing atmosphere Mini-sintering Reforming process Element migration

Resilient Si_(3)N_(4)@SiO_(2)nanowire aerogels for high-temperature electromagnetic wave transparency and thermal insulation

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Journal of Advanced Ceramics 2023年第11期12卷 2112-2122页

作者： Wei Zhang lei Su De Lu Kang Peng Min Niu lei Zhuang jian feng Hongjie Wang State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Science and Technology on Advanced Ceramic Fibers and Composites Laboratory National University of Defense TechnologyChangsha 410073China

With the development of aerospace technology,the Mach number of aircraft continues to increase,which puts forward higher performance requirements for high-temperature wave-transparent materials.Silicon nitrides have excellent mechanical properties,high-temperature stability,and oxidation resistance,but their brittleness and high dielectric constant impede their practical applications.Herein,by employing a template-assisted precursor pyrolysis method,we prepared a class of Si_(3)N_(4)@SiO_(2)nanowire aerogels(Si_(3)N_(4)@SiO_(2)NWAGs)that are assembled by Si_(3)N_(4)@SiO_(2)nanowires with diameters ranging from 386 to 631 nm.Si_(3)N_(4)@SiO_(2)NWAGs have low density of 12–31 mg∙cm^(−3),specific surface area of 4.13 m^(2)∙g^(−1),and average pore size of 68.9μm.Mechanical properties characterization shows that the aerogels exhibit reversible compressibility from 60%compressive strain and good fatigue resistance even when being compressed 100 times at set strain of 20%.The aerogels also show good thermal insulation performance(0.032 W·m^(−1)∙K^(−1) at room temperature),ablation resistance(butane blow torch),and high-temperature stability(maximum service temperature in air over 1200℃).The dielectric constant and loss of the aerogels are 1.02–1.06 and 4.3×10^(−5)–1.4×10^(−3) at room temperature,respectively.The combination of good mechanical,thermal,and dielectric properties makes Si_(3)N_(4)@SiO_(2)NWAGs promising ultralight wave-transparent and thermally insulating materials for applications at high temperatures.

关键词： electromagnetic wave transparency resilient ceramic aerogels high-temperature stability fire resistance high-temperature resistance

A Comprehensive Understanding of Dietary Effects on C.elegans Physiology

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Current Medical Science 2019年第5期39卷 679-684页

作者： Jie-jun ZHOU lei CHUN jian-feng LIU Collaborative Innovation Center for Brain Science College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Diet has been shown to play an important role in human physiology.It is a predominant exogenous factor regulating the composition of gut microbiota,and dietary intervention holds promise for treatment of diseases such as obesity,type 2 diabetes,and malnutrition.Furthermore,it was reported that diet has significant effects on physiological processes of C.elegans,including reproduction,fat storage,and aging.To reveal novel signaling pathways responsive to different diets,C.elegans and its bacterial diet were used as an interspecies model system to mimic the interaction between host and gut microbiota.Most signaling pathways identified in C.elegans are highly conserved across different species,including humans.A better understanding of these pathways can,therefore,help to develop interventions for human diseases.In this article,we summarize recent achievements on molecular mechanisms underlying the response of C.elegans to different diets and discuss their relevance to human health.

关键词： diet gut microbiota metabolites C.elegans

Gravitational wave echoes from strange quark stars in the equation of state with density-dependent quark masses

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Nuclear Science and Techniques 2023年第11期34卷 112-119页

作者： jian‑feng Xu lei Cui Zhen‑Yan Lu Cheng‑Jun Xia Guang‑Xiong Peng School of arts and sciences Suqian UniversitySuqian 223800China Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and ElectronicsHunan University of Science and TechnologyXiangtan 411201China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

According to the recent studies,the gravitational wave(GW)echoes are expected to be generated by quark stars composed of ultrastiff quark matter.The ultrastiff equations of state(EOS)for quark matter were usually obtained either by a simple bag model with artificially assigned sound velocity or by employing interacting strange quark matter(SQM)depicted by simple reparameterization and rescaling.In this study,we investigate GW echoes with EOSs for SQM in the framework of the equivparticle model with density-dependent quark masses and pairing effects.We conclude that strange quark stars(SQSs)can be sufficiently compact to possess a photon sphere capable of generating GW echoes with frequencies in the range of approximately 20 kHz.However,SQSs cannot account for the observed 72 Hz signal in GW170817 event.Furthermore,we determined that quark-pairing effects play a crucial role in enabling SQSs to satisfy the necessary conditions for producing these types of echoes.

关键词： Strange quark star Gravitational wave echoes Color-flavour-locked phase Strange quark matter

Large-scale area of magnetically anisotropic nanoparticle monolayer films deposited by MAPLE

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Journal of Materials Science & Technology 2022年第11期106卷 28-32页

作者： lei Zhang feng Xu jian Zhang Baoru Bian Yong Hu Fei Xue Juan Du Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Material Technology&EngineeringChinese Academy of SciencesNingbo 315201China Institute of Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China University of Chinese Academy of Sciences Beijing 100049China College of Sciences Northeastern UniversityShenyang 110819China Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryChinese Academy of SciencesHefei 230031China

Magnetically anisotropic nanoparticle monolayer films are of great interest for the development of ap-plications such as high-density data storage,sensors.However,the formation of large-scale magnetically anisotropic monolayer film is a challenging task.Here,we provide a new way to fabricate large-scale area of Fe_(3)O_(4) nanoparticle monolayer films by vacuum deposition technique(matrix-assisted pulsed laser evaporation,MAPLE).During the deposition process,only interactions between nanoparticles influence nanoparticle self-assembly behaviors.A strong magnetic anisotropy,characterized by in-plane and out-of-plane coercivity and saturation field obtained by DCM(dynamic cantilever magnetometry),was obtained both in cubic and spherical Fe_(3)O_(4) nanoparticle monolayer films.The inter-particle dipolar interaction but not crystal anisotropy is responsible for this effective magnetic anisotropy,which has been proved by Monte-Carlo simulations.

关键词： Nanoparticle monolayer film Magnetic anisotropy MAPLE Dynamic cantilever magnetometry Monte-Carlo simulation Dipolar interaction

Suggestion on further strengthening ultra-low emission standards for PM emission from coal-fired power plants in China

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Journal of Environmental Sciences 2023年第1期123卷 203-211页

作者： jianguo Deng Shumin Wang Jiawei Zhang Yi Zhang Jingkun jiang Yongzheng Gu Tao Han lei feng jian Gao lei Duan School of Environment Tsinghua UniversityBeijing 100084China China Energy Investment Co. Ltd.Beijing 100011China Guodian Power Development Co. Ltd.Beijing 100101China CHN ENERGY New Energy Technology Research Institute Co. Ltd.Beijing 102209China Chinese Research Academy of Environmental Sciences Beijing 100012China

China has established the largest clean coal-fired power generation system in the world by accomplishing the technological transformation of coal-fired power plants(CFPPs)to achieve ultra-low emission.The potential for further particulate matter(PM)emission reduction to achieve near-zero emission for CFPPs has become a hotspot issue.In this study,PM emission from some ultra-low emission CFPPs adopting advanced air pollutant control technologies in China was reviewed.The results revealed that the average filterable particulate matter(FPM)concentration,measured as the total particulate matter(TPM)according to the current national monitoring standard,was(1.67±0.86)mg/m^(3),which could fully achieve the ultra-low emission standard for key regions(5 mg/m^(3)),but that achieving the near-zero emission standard was difficult(1 mg/m^(3)).However,the condensable particulate matter(CPM),with an average concentration of(1.06±1.28)mg/m^(3),was generally ignored during monitoring,which led to about 38.7%underestimation of the TPM.Even considering both FPM and CPM,the TPM emission from current CFPPs would contribute to less than 5%of atmospheric PM_(2.5) concentrations in the key cities and regions in China.Therefore,further reduction in FPM emission proposed by the near-zero emission plan of CFPPs may have less environmental benefit than emission control of other anthropogenic sources.However,it is suggested that the management of CPM emission should be strengthened,and a national standard for CPM emission monitoring based on the indirect dilution method should be established for CFPPs.Those measurements are helpful for optimal operation of air pollutant control devices and continuously promoting further emission reduction.

关键词： Near-zero emission Condensable particulate matter(CPM) Indirect dilution Emission standard Technical specification for emission monitoring