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Expression of the DNA-repair protein XRCC1 and DNA-repair enzyme Ku70 mRNA in the rat cerebral cortex following global cerebral ischemia/reperfusion Is this correlated with neuroprotective effects of theanine?

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Neural Regeneration Research 2010年第1期5卷 41-46页

作者： Rongliang xue Wenchao Chen ning wang Shasha Li Department of Anesthesiology Second Affiliated Hospital Medical College of Xi'an Jiaotong University Xi'an 710004 Shaanxi ProvinceChina

BACKGROUND： Numerous studies have shown that apoptosis, caused by cerebral ischemia/reperfusion injury, is a dynamic evolving process that occurs in a time-dependent fashion. Non-apoptotic cells can result in apoptosis, with a prolonged reperfusion period and an accumulation of DNA damage. Recent studies have indicated that theanine has a protective effect on the brain. Nonetheless, there is no research relating to whether theanine is neuroprotective following brain injury. OBJECTIVE： To investigate the effects of theanine on apoptosis in the cerebral cortex and mRNA expression of the DNA repair protein, XRCC1, and DNA repair enzyme, Ku70, at various time points following global cerebral ischemia/reperfusion in rats. DESIGN, TIME AND SETTING： A randomized, controlled animal study was performed at the Pharmacological Laboratory of Animal Experimental Center of Xi＇an Jiaotong University, China, from April to October 2007. MATERIALS： Theanine （Wuhan Remote Technology Co., Ltd., China）, XRCC1, Ku70 and GAPDH primers （Shanghai Sangon Biological Engineering Technology ＆ Services Co., Ltd., China） were used in this study. METHODS： A total of 108 healthy, male Sprague Dawley rats were randomly divided into sham operation, ischemia/reperfusion and theanine groups. Each group was further divided into 6 subgroups, with six rats in each, according to reperfusion time （2, 6, 12, 24, 48 and 72 hours）. Rat models of global cerebral ischemia/reperfusion were established by the four-vessel occlusion method. Theanine （1 000 mg/kg） was injected into the caudal vein of rats in the theanine group immediately after surgery. Saline （4 mL/kg） was used in the sham operation and ischemia/reperfusion groups. The same dose was administered every 24 hours. MAIN OUTCOME MEASURES： Flow cytometry was employed to determine apoptosis of cerebral cortical neurons. Real-time reverse transcdption-polymerase chain reaction was applied to quantify the expression of XRCC1 and Ku70 mRNA in the cerebral cor

关键词： brain ischemia/reperfusion injury XRCC1 Ku70 theanine

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MADRL-based UAV swarm non-cooperative game under incomplete information

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Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen wang Fan LIU Chen HONG Jing GUO Lin ZHAO Jian xue ning HE School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of Q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium

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One-pot synthesis of a giant twisted double-layer chiral macrocycle via [4+8] imine condensation and its X-ray structure

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Chinese Chemical Letters 2024年第10期35卷 241-243页

作者： Yu Pang Min wang ning-Hua Yang Min xue Yong Yang School of Science Department of PhysicsKey Laboratory of Optical Field Manipulation of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou 310018China School of Chemistry and Chemical Engineering Key Laboratory of Surface&Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou310018China

Trifluoroacetic acid(TFA)catalyzed condensation reaction between tetraaminooxacalix[4]arene and N-alkylcarbazole-3,6-dicarbaldehyde in CH_(2)Cl2afforded a single product in 87%–89%***-defined yet undissolvable1H NMR spectra suggested formation of robust and discrete structures in solution.X-ray single crystal analysis further revealed a giant twisted double-layer chiral macrocycle in the solid state,which was formed from[4+8]condensation of the two reactants via 16 imine *** calculations discovered that only the[4+8]twisted product is thermodynamically favorable,which accounts for its highly selective and efficient formation out of a library of many other combinations.

关键词： One-pot synthesis Oxacalixarene Dynamic covalent chemistry Chiral macrocycle X-ray single crystal

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High-resolution remote thermometry based on Bi^(3+)-doped 0D zinc halide hybrids

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Science China Chemistry 2024年第8期67卷 2599-2605页

作者： Cui-Mi Shi Shu-Hua xue Jin-Yun wang Liang-Jin Xu Zhong-ning Chen State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science Technology Innovation Laboratory for Optoelectronic Information of ChinaFuzhou 350108China University of Chinese Academy of Sciences Beijing 100049China

Developing highly sensitive optical thermometers is of great significance due to their capability to enable remote and non-contact temperature measurements, rendering them highly applicable in diverse and harsh environments. Herein we report a temperature-dependent phosphor of 0D metal halide hybrid by incorporating Bi^(3+)into the(MePPh_(3))_(2)ZnCl_(4) matrix. Through Bi^(3+)doping,the initially non-luminescent(MePPh_(3))_(2) ZnCl_(4) matrix exhibits a deep-blue emission centered at 453 nm, with a photoluminescence quantum yield(PLQY) of 5.71% and a Stokes shift of 75 nm at room temperature. Experimental characterization demonstrates that exciton-like luminescence of Bi^(3+)is mainly responsible for the blue emission. Single crystals of Bi^(3+)-doped(MePPh_(3))_(2)ZnCl_(4) show an unusual correlation between photoluminescence(PL) lifetime and temperature. Particularly, the dependence of luminescence lifetime on temperature is most remarkable in the temperature range of 80 to 100 K with an exceptional sensitivity up to 0.09 K^(-1), representing one of the best levels for thermometry based on PL decay lifetime. Our work not only provides a viable strategy for designing a novel, environmentally friendly, and stable blue emitter, but also paves the way for precise thermometric application at low temperature.

关键词： lead-free hybrids Bi^(3+)doping blue emission temperature sensing

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Engineering the axial coordination of cobalt single atom catalysts for efficient photocatalytic hydrogen evolution

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Nano Research 2024年第6期17卷 5114-5121页

作者： ning Kang Lingwen Liao xue Zhang Zhen He Binlu Yu Jiahong wang Yongquan Qu Paul KChu Seeram Ramakrishna xue-Feng Yu Xin wang Licheng Bai Materials Interfaces Center Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences(CAS)Shenzhen 518055China Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Department of Chemistry City University of Hong KongKowloonHong Kong 999077China Hong Kong Branch of National Precious Metals Material Engineering Research Center(NPMM) City University of Hong KongKowloonHong Kong 999077China Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Physics and Department of Materials Science and Engineering City University of Hong KongKowloonHong Kong 999077China National University of Singapore(NUS)Centre for Nanofibers and Nanotechnology Department of Mechanical EngineeringNational University of SingaporeSingapore 117542Singapore

Improving the catalytic activity of non-noble metal single atom catalysts(SACs)has attracted considerable attention in materials *** optimizing the local electronic structure of single atom can greatly improve their catalytic activity,it often involves in-plane modulation and requires high ***,we report a novel strategy to manipulate the local electronic structure of SACs via the modulation of axial Co-S bond anchored onto graphitic carbon nitride(C_(3)N_(4))at room temperature(RT).Each Co atom is bonded to four N atoms and one S atom(Co-(N,S)/C_(3)N_(4)).Owing to the greater electronegativity of S in the Co-S bond,the local electronic structure of the Co atoms is available to be controlled at a relatively moderate ***,when employed for the photocatalytic hydrogen evolution reaction,the adsorption energy of intermediate hydrogen(H*)on the Co atoms is remarkably *** the presence of the Co-(N,S)/C_(3)N_(4)SACs,the hydrogen evolution rates reach up to 10 mmol/(g·h),which is nearly 10 and 2.5 times greater than the rates in the presence of previously reported transition metal/C_(3)N_(4)and noble platinum nanoparticles(PtNPs)/C_(3)N_(4)catalysts,*** to the tailorable axial Co-S bond in the SAC,the local electronic structure of the Co atoms can be further optimized for other photocatalytic *** axial coordination engineering strategy is universal in catalyst designing and can be used for a variety of photocatalytic applications.

关键词： transition metal single-atom local electronic structure photocatalytic hydrogen evolution graphitic carbon nitride axial coordination environment

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Enhancing dielectric properties and energy storage performance of polyvinylidene fluoride composite by surface-modified AgNbO_(3) nanoparticles

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High Voltage 2024年第4期9卷 939-947页

作者： Zhuo wang Ting Zhao Dan Wu Ying xue Zhihui Yi Jinteng Kang Ronghui Ye ning Guo Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic Materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi'anChina Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinChina

The introduction of antiferroelectric filler AgNbO_(3) into the polyvinylidene fluoride(PVDF)polymer matrix enhances its energy storage properties of ***,AgNbO_(3) and PVDF matrix are incompatible due to their distinct physical and chemical properties,resulting in poor compatibility between the two *** modification enhances the large difference in physical and chemical properties between the filler and the polymer matrix,and improves the compatibility between the two *** coupling agents(KH550,KH560),dopamine(DA),and grafted poly(methyl methacrylate)(PMMA)were used to modify the surface of AgNbO_(3) particles,and the effects of different surface modification methods on the energy storage performance of the composites were *** PVDF matrix was introduced with 0.3 wt%AgNbO_(3) particle *** results showed that the amino group in KH550 had the strongest binding with *** ester group in PMMA has a strong binding with *** epoxy group in KH560 has a weak binding with PVDF,while the amino group in DA has the worst binding with *** compatibility of the two phases in AgNbO_(3)@KH550/PVDF composites is the best,and the charge distribution on the surface of the filler is *** an electric field of 350 kV/mm,the energy storage density is 8.48 J/cm^(3).

关键词： composites composite filler

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Development of a Front End Array for Broadband Phased Array Receiver

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Research in Astronomy and Astrophysics 2024年第4期24卷 60-70页

作者： Kai wang Liang Cao Jun Ma xue-Feng Duan Hao Yan Mao-Zheng Chen Yun-Wei ning Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 8300lChina University of the Chinese Academy of Sciences Beijing 100049China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China

The receiver is a signal receiving device placed at the focus of the *** order to improve the observation efficiency,the concept of phased array receiver has been proposed in recent years,which places a small phased array at the focal plane of the reflector,and flexible pattern and beam scanning functions can be achieved through a beamforming *** combined with the element multiplexing,all beams within the entire field of view can be observed simultaneously to achieve continuous sky *** article focuses on the front-end array of phased array receiver at 0.7-1.8 GHz for QiTai Telescope,and designs a Vivaldi antenna array of PCB structure with dual line *** polarization antenna is designed to arrange in a rectangle manner by 11×*** on the simulation results of the focal field,32,18,and eight elements were selected to form one beam at 0.7,1.25,and1.8 *** analog beamforming network was constructed,and the measured gains of axial beam under uniform weighting were 19.32,13.72,and 15.22 *** the beam scanning method of reflector antenna,the pattern test of different position element sets required for PAF beam scanning was carried out under independent *** pattern optimization at 1.25 GHz was carried out by weighting method of conjugate field *** with uniform weighting,the gain,sidelobe level,and main beam direction under conjugate field matching have been *** the above test and simulation results are slightly different,which is related to the passive array and laboratory testing condition,the relevant work has accumulated experience in the development of the front-end array for the phased array receiver,and has good guiding significance for future performance verification after the array is installed on the telescope.

关键词： telescopes instrumentation:detectors techniques:radar astronomy

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Combined use of fly ash and silica to prevent the long-term strength retrogression of oil well cement set and cured at HPHT conditions

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Petroleum Science 2024年第2期21卷 1122-1134页

作者： Guo-Dong Cheng xue-Yu Pang Jin-Sheng Sun Zheng-Song Qiu Chuang-Chuang wang Jian-Kun Qin ning Li School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongChina National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Oil and Gas Engineering Research Institute(Tarim Oilfield Company) China National Petroleum CorporationTarim841000XinjiangChina

The long-term strength retrogression of silica-enriched oil well cement poses a significant threat to wellbore integrity in deep and ultra-deep wells, which is a major obstacle for deep petroleum and geothermal energy development. Previous attempts to address this problem has been unsatisfactory because they can only reduce the strength decline rate. This study presents a new solution to this problem by incorporating fly ash to the traditional silica-cement systems. The influences of fly ash and silica on the strength retrogression behavior of oil well cement systems directly set and cured under the condition of 200°C and 50 MPa are investigated. Test results indicate that the slurries containing only silica or fly ash experience severe strength retrogression from 2 to 30 d curing, while the slurries containing both fly ash and silica experience strength enhancement from 2 to 90 d. The strength test results are corroborated by further evidences from permeability tests as well as microstructure analysis of set cement. Composition of set cement evaluated by quantitative X-ray diffraction analyses with partial or no known crystal structure(PONKCS) method and thermogravimetry analyses revealed that the conversion of amorphous C-(A)-S-H to crystalline phases is the primary cause of long-term strength *** addition of fly ash can reduce the initial amount of C-(A)-S-H in the set cement, and its combined use with silica can prevent the crystallization of C-(A)-S-H, which is believed to be the working mechanism of this new admixture in improving long-term strength stability of oil well cement systems.

关键词： Fly ash Long-term strength retrogression High temperature Quantitative X-ray diffraction(QXRD) Partial or no known crystal structure(PONKCS)

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Energy transfer, anticounterfeiting, white light emission and sensing in fine-regulating series of lanthanide metal-organic frameworks

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Journal of Rare Earths 2024年第3期42卷 446-454,I0001页

作者： Juanjuan xue Yao wang Guoping Yang Yaoyu wang Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education Shaanxi Key Laboratory of Physico-Inorganic ChemistryCollege of Chemistry&Materials ScienceNorthwest UniversityXi'an710127China

Three lanthanide ions and a rigid(1,1'-biphenyl)-2,4,6-tricarboxylic acid(H_(3)bptc) ligand led to the isostructural lanthanide metal-organic frameworks(Ln-MOFs) {[Ln(bptc)(H_(2)O)_(3)]·3H_(2)O}_n(Lnbptc, Ln = Eu,Tb, Gd, Eu_(x)Tb_(1—x), Eu_(x)Gd_(1-x), Tb_(x)Gd_(1-x), and Eu_(0.12)Tb_(0.52)Gd_(0.36)). The density functional theory(DFT) and time-dependent DFT calculation were expanded on H_3bptc, which point to the occurrence of “antenna effect”. The minor diameter samples of Eubptc, Tbbptc, and Gdbptc can also be attained via the microwave synthesis and employed for handwriting anticounterfeiting. Interestingly, the typical red emission of Eu^(3+) and green emission of Tb~(3+) could be fine-tuned by Gd^(3+) via chemical mixing to be full-color emissions bimetallic doped Eu_(x)Tb_(1-x)bptc, Eu_(x)Gd_(1-x)bptc, and Tb_(x)Gd_(1-x)bptc. The above synthetic bimetallic MOFs can be fixed in positioning boxes of quick response(QR) codes with diverse emission for anticounterfeiting. The message can be decoded under the irradiation of 365 nm ultraviolet lamp while invisible in the daylight. Notably, the trimetallic doped Eu_(0.12)Tb_(0.52)Gd_(0.36)bptc emits white light with the CIE color coordinate(0.34, 0.34). Furthermore, Tbbptc is demonstrated to be a sensitive probe toward nitrobenzene and acetone with multiple mechanisms.

关键词： Metal-organic frameworks Anticounterfeiting White light-emitting Sensing Rare earths

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The Boundary Element Method for Ordinary State-Based Peridynamics

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2807-2834页

作者： xue Liang Linjuan wang State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering ScienceCollege of EngineeringPeking UniversityBeijing100871China CAPT-HEDPS and IFSA Collaborative Innovation Center of MoECollege of EngineeringPeking UniversityBeijing100871China School of Astronautics Beihang UniversityBeijing100191China

The peridynamics(PD),as a promising nonlocal continuum mechanics theory,shines in solving discontinuous *** to now,various numerical methods,such as the peridynamic mesh-free particlemethod(PD-MPM),peridynamic finite element method(PD-FEM),and peridynamic boundary element method(PD-BEM),have been ***-BEM,in particular,outperforms other methods by eliminating spurious boundary softening,efficiently handling infinite problems,and ensuring high computational ***,the existing PD-BEM is constructed exclusively for bond-based peridynamics(BBPD)with fixed Poisson’s ratio,limiting its applicability to crack propagation problems and scenarios involving infinite or semi-infinite *** this paper,we address these limitations by introducing the boundary element method(BEM)for ordinary state-based peridynamics(OSPD-BEM).Additionally,we present a crack propagationmodel embeddedwithin the framework ofOSPD-BEM to simulate crack *** validate the effectiveness of OSPD-BEM,we conduct four numerical examples:deformation under uniaxial loading,crack initiation in a double-notched specimen,wedge-splitting test,and threepoint bending *** results demonstrate the accuracy and efficiency of OSPD-BEM,highlighting its capability to successfully eliminate spurious boundary softening phenomena under varying Poisson’s ***,OSPDBEMsignificantly reduces computational time and exhibits greater consistencywith experimental results compared to PD-MPM.

关键词： Ordinary state-based peridynamics boundary element method crack propagation fracture toughness

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