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Oestrogen ameliorates blood-brain barrier damage after experimental subarachnoid haemorrhage via the SHH pathway in male rats

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Stroke & Vascular Neurology 2023年第3期8卷 217-228,I0060-I0073页

作者： Jie Zhang Haiying li Zhongmou Xu Jinxin Lu Chang Cao Haitao Shen xiang li Wanchun You Gang Chen Department of Neurosurgery&Brain and Nerve Research Laboratory First Affiliated Hospital of Soochow UniversitySuzhouJiangsuChina Institute of Stroke Research Soochow UniversitySuzhouChina

Background Sex differences affect the occurrence,progression and regression of subarachnoid haemorrhage(SAH).Oestrogen plays a protective role in alleviating the vasospasm and neuronal apoptosis induced by ***,whether oestrogen affects blood‒brain barrier(BBB)integrity has not been fully *** has been found to regulate the sonic hedgehog(SHH)signalling pathway through the oestrogen receptor in gastric cancer and adrenal glands,and the SHH signalling pathway has an important role in maintaining the BBB by upregulating the expression of tight junction *** this study,we investigated the relationship between oestrogen and the SHH signalling pathway using clinical data and established an experimental SAH model to explore whether oestrogen could ameliorate BBB damage after SAH through the SHH *** Correlations between oestrogen and the SHH pathway were analysed by patients’cerebrospinal fluid(CSF)samples and the Genotype-Tissue Expression database(GTEx).Then,an experimental rat SAH model was established using the endovascular perforation method and treated with oestrogen,oestrogen inhibitors and SHH signalling pathway ***,the effects of oestrogen on BBB damage were analysed by western blot,immunofluorescence and neurobehavioural *** ESliA detection and correlation analysis showed that oestrogen levels in patients’CSF were positively correlated with the SHH pathway,which was further verified by GTEx gene-correlation *** was found to be mainly expressed in neurons and astrocytes in rats under physiological conditions and was upregulated by oestrogen *** the SAH model,oestrogen pretreatment was found to reverse SAH-induced decreases in the SHH pathway,which were counteracted by oestrogen receptor ***,oestrogen pretreatment reduced SAH-induced BBB damage,brain oedema and neurological dysfunction,which were eliminated by SHH pathway *** In conclusion,we

关键词： damage barrier SHH

Solidification Structure of Continuous Casting Large Round Billets under Mold Electromagnetic Stirring

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Journal of Iron and Steel Research International 2016年第4期23卷 329-337页

作者： Tao SUN Feng YUE hua-jie WU Chun GUO Ying li Zhong-cun MA Metallurgical Engineering Research Institute University of Science and Technology Beijing Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beiman Special Steel Co. Ltd.

The solidification structure of a continuous casting large round billet was analyzed by a cellular-automaton-finite-element coupling model using the ProCAST software. The actual and simulated solidification structures were compared under mold electromagnetic stirring （MEMS） conditions （current of 300 A and frequency of 3 Hz）. Thereafter, the solidification structures of the large round billet were investigated under different superheats, casting speeds, and secondary cooling intensities. Finally, the effect of the MEMS current on the solidification structures was obtained under fixed superheat, casting speed, secondary cooling intensity, and MEMS frequency. The model accurately simulated the actual solidification structures of any steel, regardless of its size and the parameters used in the continuous casting process. The ratio of the central equiaxed grain zone was found to increase with decreasing superheat, increasing casting speed, decreasing secondary cooling intensity, and increasing MEMS current. The grain size obviously decreased with decreasing superheat and increasing MEMS current but was less sensitive to the casting speed and secondary cooling intensity.

关键词： continuous casting large round billet solidification structure cellular-automaton-finite-element method mold electromagnetic stirring central equiaxed grain zone grain size

A comparison of the biological,geological events and environmental backgrounds between the Neoproterozoic-Cambrian and Permian-Triassic transitions

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Science China Earth Sciences 2010年第12期53卷 1873-1884页

作者： ShuZhong Shen MaoYan Zhu xiangDong Wang Guoxiang li ChangQun Cao hua Zhang Chinese Acad Sci State Key Lab Palaeobiol & Stratig Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

The Neoproterozoic-Cambrian(N-C) and Permian-Triassic(P-T) transitions have been regarded the two most critical transitions in earth history because of the explosive biological radiation in the early Cambrian(the Cambrian Explosion) and the largest mass extinction at the *** studies suggest that these two critical transitions showed certain comparability in major evolutionary *** other words,a series of biological,geological,and geochemical events that had happened in the N-C transition occurred repeatedly during the P-T *** events included continental re-configuration related to the deep mantle dynamics,global-scale glaciations,large C-,Sr-,and S-isotope perturbations indicating atmospheric and oceanic changes,abnormal precipitation of carbonates,and associated multiple biological radiations and mass *** coupling of those events in both N-C and P-T transitions suggests that deep mantle dynamics could be a primary mechanism driving dramatic changes of environment on the earth's surface,which in turn caused major biological re-organizations.A detailed comparison of those events during the two critical transitions indicates that despite their general comparability,significant differences do exist in magnitude,duration,and *** supercontinent Rodinia began to rift before the Snowball Earth *** contrast,the supercontinent Pangea entered the dispersal stage after the greatest glaciation from the Late Carboniferous to *** data and qualitative analyses of different fossil groups show a more profound mass extinction during the N-C transition than at the end-Permian in terms of ecosystem *** is indicated by the disappearance of the whole Ediacaran biota at the N-C *** subsequent appearances of many new complex animals at phylum level in the early Cambrian mark the establishment of a brand new ***,the end-Permian mass extinction is manifested mainly by the extin

关键词： Neoproterozoic-Cambrian Permian-Triassic transition biological events geological events environmental background

Synthesis and photovoltaic performance of N-dioctylmethyl- 2,7-carbazole-alt-5,7-bis(thiophen-2-yl)-2,3-biphenylthieno[3,4-b] pyrazine copolymeric derivatives appending various donor units in phenyl moieties

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Science China Chemistry 2015年第2期58卷 301-308页

作者： Jianmin li hua Tan Fanyuan Meng Wenhong Peng Yafei Wang Yu liu Weiguo Zhu Key Lab of Environment-Friendly Chemistry and Application in Ministry of Education College of Chemistry Xiangtan University

A series of N-dioctylmethyl-2,7-carbazole-alt-5,7-bis（thiophen-2-yl）-2,3-biphenylthieno[3,4-b]pyrazine （PCz-3ThPz-Ph） co- polymeric derivatives appending various donor units in two phenyl rings, namely, PCz-3ThPz-PhTh, PCz-3ThPz-PhF1, PCz-3ThPz-PhCz, and PCz-3ThPz-PhTpa were synthesized and characterized. The effect of these appending donor units, e.g., thiophene （Th）, fluorene （F1）, carbazole （Cz）, and triarylamine （Tpa）, was investigated on dispersible, optical, electrochemical, and photovoltaic properties for their polymers. The copolymers of PCz-3ThPz-PhCz and PCz-3ThPz-PhTpa containing Cz or Tpa units exhibited higher short-circuit current density （Jsc） and power conversion efficiency （PCE） in their bulk heterojunction polymeric solar cells. The highest PCE of 1.66% and Jsc of 7.16 mA cm-2 were obtained in a device with the PCz-3ThPz-PhCz/PC61BM blend under AM 1.5 G irradiation （100 mW cm 2）; these values are 1.78 and 1.59 times higher than the corresponding values for the PCz-3ThPz-Ph-based device. When PC61BM was placed by PC71BM, the PCz-3ThPz-PhCz-based device displayed an enhanced PCE of 2.98% and a Jsc of 10.88 mA cm-2. This work demonstrated that appending additional hole-transporting units of Cz and Tpa into the side-chain of a polymer with a D-A backbone can significantly enhance the photovoltaic performance of their resultant polymers.

关键词： conjugated polymers polymer solar cells thieno[3 4-b]pyrazine functionalization of polymers

Current noises in a topological Josephson junction

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Science China(Physics,Mechanics & Astronomy) 2018年第9期61卷 75-81页

作者： Yu-Hang li Jie liu JunTao Song hua Jiang Qing-Feng Sun XinCheng Xie International Center for Quantum Materials School of Physics Peking University Beijing 100871 China Department of Applied Physics School of Science Xi'an Jiaotong University Xi'an 710049 China Department of Physics and Hebei Advanced Thin Film Laboratory Hebei Normal University Shijiazhuang 050024 China College of Physics Optoelectronics and Energy Soochow University Suzhou 215006 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Beijing 100190 China

We study the transport properties of a superconductor-quantum spin Hall insulator-superconductor Josephson junction both in the absence and in the presence of a DC bias voltage. As the system is predicted to host Majorana fermions at its interfaces,the Andreev bond states are supposed to exhibit a distinct 4π periodicity in the superconducting phase difference, namely the fractional Josephson effect. Using the non-equilibrium Green's function method, we calculate the current and the related current noise based on a tight-binding Hamiltonian. Our direct results show that the fractional Josephson effect can not be seen in equilibrium junctions. While in non-equilibrium junctions, this effect can be confirmed by the multiple Andreev reflections induced peaks of the non-equilibrium noise, which appear at discrete frequencies ω = ne V with n being an integer number.

关键词： Majorana fermions Josephson junction current noise non-equilibrium Green's function

EXPERIMENTAL INVESTIGATION OF THE FAILURE OF CASCADE LANDSliDE DAMS

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Journal of Hydrodynamics 2012年第3期24卷 430-441页

作者： NIU Zhi-pan XU Wei-lin li Nai-wen XUE Yang CHEN hua-yong State key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China Key Laboratory-of Mountain Hazards and Land Surface Processes and Institute of Mountain Hazards andEnvironment Chinese Academy of Sciences Chengdu 610041 China

This paper presents results of model tests for the landslide dam failure of a single dam and cascade dams in a sloping channel. The dams were designed to be regular trapezoid with fine sand. A new measuring method named the labeled line locating method was used to digitalize the captured instantaneous pictures. Under two different inflow discharges, the morphological evolution and the flow patterns during one dam failure and the failure of cascade dams were investigated. The results indicate that when the inflow discharge is large, the deformation pattern of the downstream dam is similar to that of the upstream dam, and both dams are characterized with the overtopping scour throughout the dam failure process. When the inflow discharge is small, the upstream dam is scoured mainly through a sluice slot formed by the longitudinal incision, and the downstream dam is characterized with the overtopping scour. The data set presented in this paper can be used for the validation of numerical models and provide a reference for the flood risk management of cascade landslide dams.

关键词： labeled lines locating method inflow discharge cascade landslide dam failure overtopping sloping flume

Biodesulfurization of vanadium-bearing titanomagnetite concentrates and pH control of bioleaching solution

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International Journal of Minerals,Metallurgy and Materials 2013年第10期20卷 925-930页

作者： Xiao-rong liu Sheng-cai Jiang Yan-jun liu Hui li hua-jun Wang School of Materials Science and Engineering Shanghai Institute of Technology China Metallurgical Mining Corporation Civil and Environmental Engineering School University of Science and Technology Beijing

Vanadium-bearing titanomagnetite concentrates were desulfurized with Acidithiobacillus ferrooxidans （A. ferrooxidans）. The sulfur content of the concentrates was reduced from 0.69wt% to 0.14wt% after bioleaching for 15 d with a 10% pulp density at 30℃. Maintaining a stable pH value during biodesulfurization was critical because of high acid consumption, resulting from a combination of nonoxidative and oxidative dissolution of pyrrhotite in acid solution. It is discovered that the citric acid-disodium hydrogen phosphate buffer of pH 2.0 can control the solution pH value smoothly in the optimal range of 2.0-3.0 for A. ferrooxidans growth. Using the buffer in the volume fraction range of 5.0%-15.0% stimulates A. ferooxidans growth and improves the biodesulfurization efficiency. Compared with the buffer-free control case, the maximum increase of biodesulfurization rate is 29.7% using a 10.0vol% buffer. Bioleaching provides an alternative process for desulfurization of vanadium-bearing titanomagnetite ores.

关键词： titanomagnetite vanadium biodesulfurization Acidithiobacillus ferrooxidans citric acid disodium hydrogenphosphate

Design of H_∞ robust fault detection filter for nonlinear time-delay systems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1733-1741页

作者： BAI Lei-shi HE li-ming TIAN Zuo-hua SHI Song-jiao Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

In this paper, the robust fault detection filter (RFDF) design problems are studied for nonlinear time-delay systems with unknown inputs. First, a reference residual model is introduced to formulate the RFDF design problem as an H∞ model-matching problem. Then appropriate input/output selection matrices are introduced to extend a performance index to the time-delay systems in time domain. The reference residual model designed according to the performance index is an optimal residual generator, which takes into account the robustness against disturbances and sensitivity to faults simultaneously. Applying robust H∞ optimization control technique, the existence conditions of the RFDF for nonlinear time-delay systems with unknown inputs are presented in terms of linear matrix inequality (LMI) formulation, independently of time delay. An illustrative design example is used to demonstrate the validity and applicability of the proposed approach.

关键词： Nonlinear time-delay systems Robust fault detection filter iRFDF H∞ optimization linear matrix inequality (LMI)

A Control Algorithm Derived from Immune Principle

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Journal of China University of Mining and Technology 2006年第3期16卷 344-348页

作者： liU Jian-hua YAN De-kun WU li-bo School oflnformation and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Department of Mathematics Linyi Normal University Linyi Shandong 276005 China

Artificial immune systems (AIS) are biologically inspired problem solvers having been successfully applied in many fields. A controller was designed according to the interactive mechanism between immune molecules. Multiform antigens were constructed and corresponding antibodies designed. The concept of “antibiotic” is presented, whose features and injection time as well as construction method discussed. Based on biological immune mechanism, some fuzzy rules are summarized and used in constructing the controller. The result shows that this controller is simple in structure and can be easily computed, so it is suitable for real time control. The control variable can change adaptively according to the error and its change tendency. Therefore the controller is very flexible and can be directly used in controlling some nonlinear plants. To test the validity of the algorithm, two simulation examples are given, one is linear, and the other is nonlinear. The Simulation results indicate that the control performance of this algorithm is better than that of the conventional PID.

关键词： artificial immune system control antigen antibody antibiotic