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Urotensin Ⅱ inhibits electrical activity of hippocampal CA1 neurons by potentiating the GABA_A receptor-mediated Cl^- current

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Neuroscience Bulletin 2006年第2期22卷 110-114页

作者： yu-ming wu Ru WANG Rui-Rong HE Department of Physiology Institute of Basic Medicine Hebei Medical University Shijiazhuang 050017China

Objective To examine the effects of urotensin Ⅱ （UⅡ） on the discharges of neurons in CA1 area of hippocampal slices by using extracellular recording technique. Results ①In response to the application of UⅡ （0.3, 3.0, 30.0,300.0 nmol/L, n = 77） into the perfusate for 2 min, the spontaneous discharge rates （SDR） of 63/77 （81.8% ） neurons were significantly decreased in a dose-dependent manner. ②Pretreatment with bicuculline（BIC, 100 μmol/L）, a specific GABAs receptor antagonist, led to a marked increase in the SDR of 6/7 （85.71%） neurons in an epileptiform pattern. The increased discharges were not significantly changed after UⅡ （30.0 nmol/L） was applied into the perfusate for 2 min. ③Pretreatment with picrotoxin （ PIC, 50 μmol/L）, a selective blocker of Cl^- channel, led to an increase in the SDR of all 8/8（ 100% ） neurons. The increased discharges were not influenced by the UⅡ （30.0 nmol/L） applied. ④Application of nitric oxide synthase （NOS） inhibitor N^G nitro-L-arginine methyl ester （L-NAME, 50μmol/L） into the perfusate for 2 min also significantly augmented the SDR of 14/16 （87.5 % ） neurons , then UⅡ （30.0 nmol/L） applied into the perfusate reduced the increased the SDR of all 14/14 （ 100% ） neurons. Conclusion These results suggest that UⅡ may decrease neuronal activity by potentiating GABAA receptor-mediated CI current in hippocampal CA1 neurons, and involved with the mediation of nitric oxide.

关键词： hippocampal slice urotensin Ⅱ bicuculline L-NAME picrotoxin

Microstructure recognition of steels by machine learning based on visual attention mechanism

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Journal of Iron and Steel Research International 2024年第4期31卷 909-923页

作者： Xing-yu Chen Lin Cheng Cheng-yang Hu yu-peng Zhang Kai-ming wu The State Key Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)Metallic Composite Materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the *** representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction *** is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure *** reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

Thermodynamic phase transition and winding number for the third-order Lovelock black hole

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Chinese Physics C 2024年第9期48卷 188-198页

作者： yu-Shan Wang Zhen-ming Xu Bin wu School of Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

Phase transition is important for understanding the nature and evolution of the black hole thermodynamic *** this study,we predicted the phase transition of the third-order Lovelock black hole using the winding number... 详细信息

关键词： black hole thermodynamics Lovelock black hole phase transition

A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures

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Petroleum Science 2024年第4期21卷 2583-2599页

作者： Jun Li ming-Yi wu Xu Han Si-yuan He Ze-yu Lin State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Sichuan Particles Energy and Technology Co. Ltd Chongqing Industry Polytechnic College Petroleum Systems Engineering Faculty of Engineering and Applied Science University of Regina

Low-permeability reservoirs are generally characterized by low porosity and low permeability. Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor. In recent years, hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing ***, the transportation of the proppant is inefficient in the low-viscosity fluid, and the proppant has a low piling-up height in fracture channels. These key challenges restrict the fluid(natural gas or oil) flow in fracture channels and their functional flow areas, reducing the profits of hydrocarbon *** study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber. Its structure was similar to that of dandelion seeds, and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional ***, the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model, rough fracture model,narrow fracture model, complex fracture model, large-scale single fracture model, and small-scale single fracture model). Experimental results indicated that, compared with the traditional proppant, the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid. Compared with the traditional proppant, the dandelionbased bionic proppant had 0.1-4 times longer transportation length, 0.3-5 times higher piling-up height, and 2-10 times larger placement area. The newly developed proppant also had some other extraordinary features. The tortuosity of the fracture did not influence the transportation of the novel proppant. This proppant could easily enter the branch fracture and n

关键词： Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation

Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li ming-Wei Zhang Ji-wu Xin Lei Wei Wen-yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

Stress corrosion cracking behavior of buried oil and gas pipeline steel under the coexistence of magnetic field and sulfate-reducing bacteria

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Petroleum Science 2024年第2期21卷 1320-1332页

作者： Jian-yu He Fei Xie Dan Wang Guang-Xin Liu ming wu yue Qin College of Petroleum Engineering Liaoning Petrochemical UniversityFushun113001LiaoningChina Key Laboratory of Oil and Gas Storage and Transportation Technology in Liaoning Province Fushun113001LiaoningChina State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China PipeChina West East Gas Pipeline Company Shanghai200120China

Magnetic field and microorganisms are important factors influencing the stress corrosion cracking(SCC)of buried oil and gas pipelines. Once SCC occurs in buried pipelines, it will cause serious hazards to the soil environment. The SCC behavior of X80 pipeline steel under the magnetic field and sulfate-reducing bacteria(SRB) environment was investigated by immersion tests, electrochemical tests, and slow strain rate tensile(SSRT) tests. The results showed that the corrosion and SCC sensitivity of X80 steel decreased with increasing the magnetic field strength in the sterile environment. The SCC sensitivity was higher in the biotic environment inoculated with SRB, but it also decreased with increasing magnetic field strength, which was due to the magnetic field reduces microbial activity and promotes the formation of dense film layer. This work provided theoretical guidance on the prevention of SCC in pipeline steel under magnetic field and SRB coexistence.

关键词： Magnetic field Sulfate-reducing bacteria Film layer Stress corrosion cracking Oil and gas pipelines

Effects of phytoestrogen genistein on myocardial ischemia/reperfusion injury and apoptosis in rabbits

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Acta Pharmacologica Sinica 2004年第3期25卷 52-58页

作者： En-sheng JI,Hua yuE,yu-ming wu,Rui-rong HE1 Department of Physiology,Institute ofBasic Medicine,Hebei MedicalUniversity,Shijiazhuang 050017,China Department of Physiology Institute of Basic Medicine Hebei Medical University Shijiazhuang 050017

AIM: To study the effect of genistein (GST) on rabbit heart ischemia/reperfusion (I/R) injury. METHODS: Rabbit heart I/R injury was induced by occluding the left anterior descending coronary artery for 45 min and reperfusing for 180 min. GST (1.0 mg/kg) was intravenously injected 5 min before heart ischemia. Hemodynamic data, infarct size, and cardiomyocytic apoptosis were measured. The pathologic changes of I/R myocardium were observed. RESULTS: During the I/R, heart rate, mean arterial blood pressure, myocardial oxygen consumption, left ventricu- lar (LV) –dp/dtmax and +dp/dtmax were decreased progressively. The infarct size was occupied 60.23 %±3.97 % (% of area at risk) in vehicle +I/R group while GST reduced the infarct size to 39.62 %±4.30 % (P<0.01). DNA ladder patter in myocardium was revealed by agarose gel electrophoresis in vehicle +I/R group while was not found in GST+I/R group. Apoptotic cardiomyocytes were sparse within ischemic myocardium at risk in GST+I/R group as compared with that in vehicle +I/R group (TUNEL stain). Apoptosis rate in ischemic myocardium from vehicle +I/R and GST+I/R groups detected by flow cytometry were 15.33 %±1.31 % and 3.88 %±0.33 %, respectively. Fas and Bax protein expressions in ischemic myocardium of vehicle +I/R group were higher than that in GST+I/R group (P<0.01). Bcl-2/Bax ratio in vehicle +I/R group was lower than that in nonischemic myocar- dium (P<0.01), while in GST+I/R group, the Bcl-2/Bax ratio was higher than that in vehicle +I/R group (P<0.01). CONCLUSION: GST reduced infarct size and apoptosis of myocytes in I/R rabbit heart.

关键词： genistein reperfusion injury apoptosis rabbits

The pseudospectrum and spectrum(in)stability of quantum corrected Schwarzschild black hole

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 55-75页

作者： Li-ming Cao Jia-Ning Chen Liang-Bi wu Libo Xie yu-Sen Zhou School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China Peng Huanwu Center for Fundamental Theory Hefei 230026China Interdisciplinary Center for Theoretical Study and Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

In this study,we investigate the pseudospectrum and spectrum(in)stability of quantum corrected Schwarzschild black ***,we use the hyperboloidal framework to cast the quasinormal mode(QNM)problem into an eigenvalue problem associated with a non-selfadjoint operator,and then the spectrum and pseudospectrum are ***,the invariant subspace method is exploited to improve the computational efficiency for *** investigation into the spectrum(in)stability entails two main *** the one hand,we calculate the spectra of the quantum corrected black hole,then by the means of the migration ratio,the impact of the quantum correction effect on the Schwarzschild black hole has been *** results indicate that the so-called“migration ratio instability”will occur for small black holes with small angular momentum number *** the eikonal limit,the migration ratios remain the same for each *** the other hand,we study the spectrum(in)stability of the quantum corrected black hole by directly adding some particular perturbations into the effective potential,where perturbations are located at the event horizon and null infinity,*** are two interesting observations under the same perturbation energy ***,perturbations at infinity are more capable of generating spectrum instability than those at the event ***,we find that the peak distribution can lead to the instability of QNM spectrum more efficiently than the average distribution.

关键词： quasinormal modes pseudospectrum hyperboloidal coordinate

NbN quantum dots anchored hollow carbon nanorods as efficient polysulfide immobilizer and lithium stabilizer for Li-S full batteries

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Journal of Energy Chemistry 2024年第1期88卷 260-271,I0007页

作者： Fei Ma Zhuo Chen Katam Srinivas Ziheng Zhang yu wu Dawei Liu Hesheng yu yue Wang Xinsheng Li ming-qiang Zhu Qi wu yuanfu Chen School of Integrated Circuit Science and Engineering and State Key Laboratory of Electronic Thin Films and Integrated DevicesUniversity of Electronic Science and TechnologyChengdu 610054SichuanChina College of Science and Institute of Oxygen Supply Center of Tibetan Studies(Everest Research Institute)Tibet UniversityLhasa 850000TibetChina College of Mechanical and Electronic Engineering Northwest A&F UniversityXianyang 712100ShaanxiChina

The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)*** simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full *** functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite *** a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 *** at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 *** study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode.

关键词： Dual-functional host NbN quantum dots Shuttle effect Dendrite-free Li anode Li-S full batteries