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The highest melting point material:Searched by Bayesian global optimization with deep potential molecular dynamics

Journal of Advanced Ceramics 2023年第4期12卷 803-814页

作者： Yinan Wang Bo Wen Xingjian Jiao Ya Li Lei Chen Yujin Wang Fu-Zhi Dai Artificial Intelligence for science institute Beijing 100084China science and Technology on Advanced Functional Composite Laboratory Aerospace Research Institute of Materials&Processing TechnologyBeijing 100076China College of Computer science and Technology Heilongjiang Institute of TechnologyHarbin 150001China institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China Key Laboratory of Advanced Structural-Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China DP Technology Bejing 100080China

The interest in refractory materials is increasing rapidly in recent decades due to the development of hypersonic ***,the substance that has the highest melting point(Tm)keeps a secret,since precise measurements in extreme conditions are overwhelmingly *** the present work,an accurate deep potential(DP)model of a Hf-Ta-C-N system was first trained,and then applied to search for the highest melting point material by molecular dynamics(MD)simulation and Bayesian global optimization(BGO).The predicted melting points agree well with the experiments and confirm that carbon site vacancies can enhance the melting point of rock-saltstructure *** solid solution with N is verified as another new and more effective melting point enhancing approach for HfC,while a conventional routing of the solid solution with Ta(e.g.,HfTa_(4)C_(5))is not suggested to result in a maximum melting *** highest melting point(~4236 K)is achieved with the composition of HfCo.638No.271,which is~80 K higher than the highest value in a Hf-C binary *** mechanism of the N addition is believed to be unstable C-N and N-N bonds in liquid phase,which reduces liquid phase entropy and renders the liquid phase less *** improved melting point and less gas generation during oxidation by the addition of N provide a new routing to modify thermal protection materials for the hypersonic vehicles.

关键词： melting point(T_(m)) carbides carbonitrides deep potential(DP) Bayesiannglobal optimization(BGO)

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Optimization of inductively coupled plasma etching for low nanometer scale air-hole arrays in two-dimensional GaAs-based photonic crystals

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Journal of Semiconductors 2010年第1期31卷 9-13页

作者：彭银生叶小玲徐波金鹏牛洁斌贾锐王占国 Key Laboratory of Semiconductor Materials science Institute of SemiconductorsChinese Academy of Sciences institute of Microelectronics Chinese Academy of Sciences

This paper mainly describes fabrication of two-dimensional GaAs-based photonic crystals with low nanometer scale air-hole arrays using an inductively coupled plasma （ICP） etching system. The sidewall profile and surface characteristics of the photonic crystals are systematically investigated as a function of process parameters including ICP power, RF power and pressure. Various ICP powers have no significant effect on the verticality of air-hole sidewall and surface smoothness. In contrast, RF power and chamber pressure play a remarkable role in improving sidewall verticality and surface characteristics of photonic crystals indicating different etching mechanisms for low nanometer scale photonic crystals. The desired photonic crystals have been achieved with hole diameters as low as 130 nm with smooth and vertical profiles by developing a suitable ICP processes. The influence of the ICP parameters on this device system are analyzed mainly by scanning electron microscopy. This fabrication approach is not limited to GaAs material, and may be efficiently applied to the development of most two-dimensional photonic crystal slabs.

关键词： photonic crystal GaAs inductively coupled plasma etching scanning electron microscopy

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Change of Iodine Load and Thyroid Homeostasis Induced by Ammonium Perchlorate in Rats

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Journal of Huazhong University of science and Technology(medical sciences) 2014年第5期34卷 672-678页

作者：陈红霞丁淼鸿刘琴彭开良 institute of Biomedicine Taihe HospitalHubei University of Medicine Department of Occupational and Environmental Health School of Public HealthTongji Medical CollegeHuazhong University of Science and Technology

Ammonium perchlorate （AP）, mainly used as solid propellants, was reported to interfere with homeostasis via competitive inhibition of iodide uptake. However, detailed mechanisms remain to be elucidated. In this study, AP was administered at 0, 130, 260 and 520 mg/kg every day to 24 male SD rats for 13 weeks. The concentrations of iodine in urine, serum thyroid hormones levels, to- tal iodine, relative iodine and total protein, and malondialdehyde （MDA）, superoxide dismutase （SOD） and catalase （CAT） activity in thyroid tissues were measured, respectively. Our results showed that high-dose perchlorate induced a significant increase in urinary iodine and serum thyroid stimu- lating hormone （TSH）, with a decrease of total iodine and relative iodine content. Meanwhile, free thyroxine （FT4） was decreased and CAT activity was remarkably increased. Particularly, the CAT activity was increased in a dose-dependent manner. These results suggested that CAT might be en- hanced to promote the synthesis of iodine, resulting in elevated urinary iodine level. Furthermore, these findings suggested that iodine in the urine and CAT activity in the thyroid might be used as biomarkers for exposure to AP, associated with thyroid hormone indicators such as TSH. FT4.

关键词： ammonium perchlorate thyroid hormones urinary iodine catalase activity

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Mesenchymal stem cells-derived exosomes ameliorate blue light stimulation in retinal pigment epithelium cells and retinal laser injury by VEGF-dependent mechanism

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International Journal of Ophthalmology(English edition) 2018年第4期11卷 559-566页

作者： Guang-Hui He Wei Zhang Ying-Xue Ma Jing Yang Li Chen Jian Song Song Chen Tianjin Eye Hospital Tianjin Key Lab of Ophthalmologyand Visual ScienceTianjin Eye InstituteClinical College of OphthalmologyTianjin Medical UniversityTianjin 300020China

AIM： To observe the effect of exosomes derived from human umbilical cord blood mesenchymal stem cells（h UCMSCs） on the expression of vascular endothelial growth factor-A（VEGF-A） in blue light injured human retinal pigment epithelial（RPE） cells and laser-induced choroidal neovascularization（CNV） in ***： Exosomes were isolated from h UCMSCs and characterized by transmission electron microscope and Western blot. MSCs-derived exosomes were cultured with RPE cells exposed to blue light. The m RNA and protein expression of VEGF-A were determined by real time-polymerase chain reaction（PCR） and Western blot, respectively. Immunofluorescence assay was used for the detection of the expression level of VEGF-A. We injected different doses of MSCs-derived exosomes intravitreally to observe and compare their effects in a mouse model of laserinduced retinal injury. The histological structure of CNV in rats was inspected by hematoxylin-eosin（HE） staining and fundus fluorescein angiography. The expression of VEGF-A was detected by ***： Exosomes exhibited the typical characteristic morphology（cup-shaped） and size（diameter between 50 and 150 nm）. The exosomes marker, CD63, and h UCMSCs marker, CD90, showed a robust presence. In vitro, MSCsderived exosomes downregulated the m RNA（Exo-L： t=6.485, 7.959, 9.286; Exo-M： t=7.517, 10.170, 13.413; Exo-H： t=10.317, 12.234, 14.592, P〈0.05） and protein（Exo-L： t=2.945, 4.477, 6.657; Exo-M： t=4.713, 6.421, 8.836; Exo-H：t=6.539, 12.194, 12.783; P〈0.05） expression of VEGF-A in RPE cells after blue light stimulation. In vivo, we found that the MSCs-derived exosomes reduced damage, distinctly downregulated VEGF-A（Exo-H： t=0.957, 1.382; P〈0.05）, and gradually improved the histological structures of CNV for a better visual function（Exo-L： 0.346, Exo-M： 3.382, Exo-H： 8.571; P〈0.05）. CONCLUSION： MSCs-derived exosomes ameliorate blue light stimulation in RPE cells and laser-induced retinal injury via downregulation of VEGF

关键词： exosome human umbilical cord mesenchymal stem cell retinal pigment epithelial cell choroidal neovascularization vascular endothelial growth factor

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DYNAMICAL LOW ENERGY ELECTRON DIFFRACTION ANALYSIS FOR Cs/GRAPHITE(0001)-(√3×√3)R30°SURFACE

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Chinese Physics Letters 1989年第1期6卷 20-23页

作者： HU Zipu LI Jia WU Naijuan Deparment of Material science University of Science and Technology of ChinaHefei institute of Physics Academia SinicaBeijing

A model incorporating(Cs-A-ABAB)stacking with Cs atoms chemisorbed in hollow sites 2.70A above the top graphite plane and the two top graphite layers shear-shifted to AA stacking and expanded to a separation of 3.85A is the most reliable structure for Cs/graphite(0001)-(√3×√3)*** coexisting diffraction pattern including the diffraction ring and another set of (√3×√3) diffraction pattern which has a 30°rotation angle with respect to the normal(√3×√3)R3O°diffraction pattern could be *** consider this strueture to be in a prein ter cal ation state.

关键词： state. stacking rotation

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Low-frequency Stimulation at the Subiculum is Anti-convulsant and Anti-drug-resistant in a Mouse Model of Lamotrigine-resistant Temporal Lobe Epilepsy

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Neuroscience Bulletin 2020年第6期36卷 654-658页

作者： Yeping Ruan Cenglin Xu Jile Lan Jiazhen Nao Shuo Zhang Fei Fan Yi Wang Zhong Chen College of Pharmaceutical science Zhejiang Chinese Medical UniversityHangzhou 310000China Key Laboratory of medical Neurobiology of National Health Commission and Chinese Academy of medical sciences Institute of Pharmacology and ToxicologyCollege of Pharmaceutical SciencesZhejiang UniversityHangzhou 310000China

Dear Editor,Epilepsy is a common neurological *** 30%of epileptic patients develop resistance to antiepileptic drugs(AEDs),and are considered to have refractory or drugresistant epilepsy[1].Based on the time course over which drug-resistance develops,refractory epilepsy can be further divided into an early-onset type(drug-resistance more likely innate and correlated with gene mutations)and a delayed-onset type(drug-resistance emerges after a period of medication)[2].

关键词： epilepsy drug drugs

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Emotion Recognition Using Cloud Model

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Chinese Journal of Electronics 2019年第3期28卷 470-474页

作者： WANG Shuliang CHI Hehua YUAN Ziqiang GENG Jing School of Computer science Wuhan University School of software Beijing Institute of Technology Goergen institute for Data science University of Rochester

Emotions often facilitate interactions among human beings, but the big variation of human emotional states make a negative effect on the reliable emotion recognition. We propose a novel algorithm to extract common features for each type of emotional states which can reliably present human emotions. To uncover the common features from uncertain emotional states,the backward cloud generator is used to discover {Ex,En, He} by integrating randomness and fuzziness. Finally,the proposed method for emotion recognition is verified on the common facial expression datasets, the Extended Cohn-Kanade(CK+) dataset and the Japanese female facial expression(JAFFE). The results are satisfactory,which shows cloud model is potentially useful in pattern recognition and machines learning.

关键词： Cloud model Feature extraction Human-machine interaction Emotion recognition

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Rapid Detection of Irreversible Acetylcholineasterase Inhibitor by Mass Spectrometry Assay

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Chinese Journal of Chemistry 2012年第8期30卷 1788-1792页

作者：蔡婷婷张立汪蓉梁晨赵武生傅得锋张玉荣郭寅龙 Shanghai Mass Spectrometry Center Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Shanghai institute of Forensic science Shanghai 200083China Jiangsu institute of Forensic science NanjinJiangsu 210024China Zhejiang institute of Forensic science HangzhouZhejiang 310009China

Here we developed a rapid method to detect acetylcholinesterase （ACHE） activity by matrix-assisted laser de- sorption/ionization Fourier transform mass spectrometry （MALDI-FTMS） for screening irreversible AChE inhibi- tors. Due to its good salt-tolerance and low sample consumption, MALDI-FTMS could facilitate rapid detection, especially detection in real application. AChE activity was determined through calculating abundance of substrate and product in mass spectrometry. By this approach, we investigated the relation of organophosphorous （OP） con- centrations and AChE inhibition. Shown in different inhibition curves from different OP pesticides, enzyme inhibi- tions still kept good correlation with concentration of OPs. Finally, this AChE-inhibited method was applied to screen whole bloods of four decedents and discuss their death reason. In contrast to healthy persons, three of dece- dents showed low AChE activity, and probably died for irreversible AChE inhibitors. Through the following de- tecting in GC-MS/MS, the possible death reason of these three decedents was confirmed, and another decedent actually died for sumicidin, a non-AChE inhibitor. It demonstrated that screening irreversible AChE inhibitors by detecting enzyme activity in MALDI-FTMS provided fast and accurate analysis results and excluded another toxicants not functioning on ACHE. This method offered alternative choices for indicating the existence of enzyme inhibitors.

关键词： acetylcholinesterase irreversible inhibitor organophosphorous pesticide mass spectrometry rapiddetection

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Anticancer Effect of Curcumin on Human B Cell non-Hodgkin's Lymphoma

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Journal of Huazhong University of science and Technology(medical sciences) 2005年第4期25卷 404-407页

作者：孙春艳刘新月陈燕刘芳 institute of Hematology Union Hospital Tongji Medical college Huazhong University of Science and Technology Wuhan 430022 China

Summary： To explore the anticancer effect of curcumin on human B cell non Hodgkin＇s lymphoma and compare its effects on human B cell non Hodgkin＇s lymphoma cells and normal peripheral blood mononuclear cells （NPBMNCs）. MTT assay was used to study the effect of curcumin on the growth of Raji cells and NPBMNCs. The effect of curcumin on the apoptosis of Raji cells and NPBMNC were studied by flow cytometry and TDT-mediated dUTP nick and labeling （TUNEL）. The effect of curcumin on the cell cycle of Raji cells were examined by propidium iodide staining flow cytometry. The results showed that curcumin strongly inhibited proliferation of Raji cells, 24 h IC50, for Raji cells was 22.8±1.82μmol/l, and curcumin induced Raji cell apoptosis in a time-and dose-dependent manner. Raji cells treated with curcumin showed G0/G1 or G2/M phase increase and S phase decrease. However, curcumin did not demonstrate apparent proliferation inhibition and apoptosis induction in NPBMNCs. It was concluded that curcumin is able to inhibit the proliferation of Raji cells by regulating the cell cycle and inducing the cell apoptosis. Morever, curcumin has low toxicity on NPBMNCs but can selectively induce apoptosis in Raji cells.

关键词： Raji cell curcumin apoptosis cell cycle selectivity

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Neurodynamics analysis of brain information transmission

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Applied Mathematics and Mechanics(English Edition) 2009年第11期30卷 1415-1428页

作者：王如彬张志康 Chi K. Tse institute for Cognitive Neurodynamics School of Information Science and EngineeringEast China University of Science and Technology institute for Cognitive Neurodynamics School of Information Science and EngineeringEast China University of Science and Technology Department of Electronic and Information Engineering The Hong Kong Polytechnic UniversityKowloon

This paper proposes a model of neural networks consisting of populations of perceptive neurons, inter-neurons, and motor neurons according to the theory of stochastic phase resetting dynamics. According to this model, the dynamical characteristics of neural networks are studied in three coupling cases, namely, series and parallel coupling, series coupling, and unilateral coupling. The results show that the indentified structure of neural networks enables the basic characteristics of neural information processing to be described in terms of the actions of both the optional motor and the reflected motor. The excitation of local neural networks is caused by the action of the optional motor. In particular, the excitation of the neural population caused by the action of the optional motor in the motor cortex is larger than that caused by the action of the reflected motor. This phenomenon indicates that there are more neurons participating in the neural information processing and the excited synchronization motion under the action of the optional motor.

关键词： serial and parallel model of neural networks phase coding synchronousmotion perception neuron inter-neuron motor neuron population of neural oscillators

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