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Place of Exercise Echocardiography in Stable Coronary Artery Disease in Sub-Saharan Africa:A Series in Senegal

World Journal of Cardiovascular Diseases 2020年第1期10卷 19-29页

作者： F.Aw m.B.Ndiaye C.m.B.m.Diop S.A.Sarr J.S.mingou m.T.Diouf m.m.Ka m.Ndiaye Hariniaina Ravaoavy m.Bodian A.A.Ngaide m.Dioum m.Leye A.mbaye A.D.Kane A.Kane m.diao S.A.Ba Cardiology Department Teaching Hospital Aristide Le DantecDakarSenegal Cardiology Department General Hospital of Grand YoffDakarSenegal Cardiology Department Teaching National Hospital of Fann Le DantecDakarSenegal Research and Training Unit of Thies ThiesSenegal Cardiology Department Regional Hospital of Saint LouisSaint LouisSenegal Cardiology Department Dalal Jamm HospitalDakarSenegal

Introduction: Exercise echocardiography is a non-invasive technique that occupies a special place for the detection of stable coronary disease. The main objective of this study was to report our experience and assess our practice in the diagnosis of stable coronaryartery disease. methodology: We conducted a retrospective study, descriptive over a period of 34 months, from December 1, 2016 to September 30, 2019. All the patients received during the study period for stress echocardiography as part of a suspicion of stable coronary artery disease were included. A total of 100 examinations were completed during the study period. Results: Ninety (90) exams were studied. There were 56 men or a sex-ratio of 1.64. The mean age was of 57.3 ± 10 years. Hypertension (31 patients or 62%) was the most frequent risk factor. Typical chest pain was noticed in 45 patients (52.3%). The pre-test probability was intermediate in 77 patients (89.5%). Echocardiography at rest was normal in 86 patients (95.6%). A total of 62 tests were negative (69%) and 02 (2.2%) were non-contributory. Ten tests (10) of 26 electrical positive tests were associated with segmental kinetics disorders. In the 10 patients who had exercise kinetic disorders, 08 had coronary angiography. It was normal in 04 of them. The positive predictive value of exercise echography was 50% in our study. In a patient with a negative exercise echocardiography with a high clinical probability of coronary disease, the coronary angiography showed a two-vessel impairment with an intermediate lesion of Cx2 and an intermediate lesion of RCA2. It thus constitutes a false negative. Sensitivity was 80% in our study. We noticed an incident like non-sustained ventricular tachycardia. Conclusion: Exercise echocardiography is a safe and reliable examination for the diagnosis of stable coronary artery disease. A good selection of patients based on the clinical probability of coronary ischemia should improve our sensitivity. This is even more

关键词： Exercise Echocardiography Coronary Artery Disease

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On the Vertex Cover Number of 3-Uniform Hypergraph

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Journal of the Operations Research Society of China 2021年第2期9卷 427-440页

作者： Zhuo diao School of Statistics and mathematics Central University of Finance and EconomicsBeijing 100081China

Given a hypergraph H(V,E),a set of vertices S⊆V is a vertex cover if every edge has at least one vertex in *** vertex cover number is the minimum cardinality of a vertex cover,denoted byτ(H).In this paper,we prove that for every 3-uniform connected hypergraph H(V,E),τ(H)≤2m3+1/3 holds on where m is the number of ***,the equality holds on if and only if H(V,E)is a hypertree with perfect matching.

关键词： 3-Uniform hypergraph Vertex cover Hypertree Perfect matching

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CONDITION NUmBER FOR WEIGHTED LINEAR LEAST SQUARES PROBLEm

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Journal of Computational mathematics 2007年第5期25卷 561-572页

作者： Yimin Wei Huaian diao Sanzheng Qiao School of mathematical Sciences and Key Laboratory of mathematics for Nonlinear Sciences Fudan University Shanghai 200433 China Department of mathematics The City University of Hong Kong 83 Tat Chee Avenue Kowloon Hong Kong Department of Computing and Software McMaster University Hamilton Ontario L8S 4LT Canada

In this paper, we investigate the condition numbers for the generalized matrix inversion and the rank deficient linear least squares problem： minx ｜｜Ax- b｜｜2, where A is an m-by-n （m ≥ n） rank deficient matrix. We first derive an explicit expression for the condition number in the weighted Frobenius norm ｜｜ [AT,βb] ｜｜F of the data A and b, where T is a positive diagonal matrix and β is a positive scalar. We then discuss the sensitivity of the standard 2-norm condition numbers for the generalized matrix inversion and rank deficient least squares and establish relations between the condition numbers and their condition numbers called level-2 condition numbers.

关键词： moore-Penrose inverse Condition number Linear least squares.

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A double-edged sword:The HBV-induced non-coding RNAs alterations in hepatocellular carcinoma

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BIOCELL 2023年第1期47卷 27-32页

作者： TIANXING LIU HONGYAN diao Department of Cell and Systems Biology University of TorontoTorontoOntarioM5S1A1Canada State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou310003China

Non-coding RNAs are speculated to exert important regulatory functions at the level of gene expression,oncogenesis,and many other *** B virus(HBV)infection is a leading cause of hepatocellular carcinoma(HCC),and some studies have shown that the expression of non-coding RNAs has an assignable effect on the development of HBV-induced *** this context,the functions and molecular mechanisms of the HBVinduced non-coding RNA expression in the development of hepatoma have attracted increasing *** review covers the progress in the exploration of the relationship between HBV-induced hepatoma and non-coding RNA expression,cataloging the recent reports about the roles of non-coding RNAs in HBV-induced hepatoma into five classes,including(1)modulation of metabolism in hepatic cancer,(2)aggravation of inflammation and hepatic fibrosis,(3)alteration of the tumor immune microenvironment,(4)non-coding RNA N6-methyladenosine modification,and a seemingly opposite process,(5)the suppression of the progression of HBV-related *** evidence supports non-coding RNAs as promising novel targets for the early diagnosis and treatments for HCC.

关键词： Non-coding RNA Hepatitis B virus Hepatocellular cancer

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Testing the Coincidence Problem with Strong Gravitational Lens,Type Ia Supernovae and Hubble Parameter Observational Data

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Research in Astronomy and Astrophysics 2022年第11期22卷 214-222页

作者： Jingwang diao Yu Pan Wenxiao Xu School of Science Chongqing University of Posts and TelecommunicationsChongqing 400065China

In this paper,we use three different kinds of observational data,including 130 strong gravitational lensing(SGL)systems,type Ia supernovae(SNeIa:Pantheon and Union2.1)and 31 Hubble parameter data points(H(z))from cosmic chronometers to constrain the phenomenological model(ρ_(x)∝ρ_(m)a^(ξ)).By combining these three kinds of data(Union2.1+SGL+H(z)),we get the parameter value at the confidence interval of 2σ,Ω_(X,0)=0.69±0.34,ω_(x)=−1.24±0.61,ξ=3.8±3.9 and H_(0)=70.22±0.86 kms^(−1) mpc^(−1).According to our results,we find that theΛCDm model is still the model which is in best agreement with the observational data at present,and the coincidence problem is not *** addition,the Ω_(X) and Ω_(m) have the same order of magnitude in 00.645,it is necessary to introduce the dark energy interacting with dark matter.

关键词： (cosmology:)cosmological parameters (cosmology:)dark energy cosmology:observations

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Improved electron capture capability of field-assisted exponential-doping GaN nanowire array photocathode

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Journal of materials Science & Technology 2020年第7期42卷 54-62页

作者： Lei Liu Feifei Lu Sihao Xia Yu diao Jian Tian Department of Optoelectronic Technology School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China

The exponential-doping GaN nanowire arrays(GaN NWAs)photocathode has a"light-trapping effect",and the built-in electric field can promote the concentration of the photogene rated carrier center to the top surface of the ***,in the preparation ofactual NWAs photocathodes,the problem that photons emitted from the sides of the nanowires cannot be effectively collected has been *** proposed field-assisted exponential-doping GaN NWAs can bend the motion trajectory of the emitted electrons toward the collecting *** this study,the quantum efficiency(QE)and collection efficiency(CE)of the external field-assisted exponential-doping GaN NWAs photocathode are derived based on the two-dimensional carrier diffusion equation and the initial energy and angular distribution,*** a field-assisted exponential-doping GaN NWAs with a width d=200 nm and a height H=400 nm,the optimal structural parameters are obtained:the incident angleθ=50°and the nanowire spacing is L=335.6 *** this basis,the field intensity of 0.5 V/μm can maximize the CE of the *** the results show that the field-assisted approach does contribute to the collection of emitted electrons,which can provide theoretical guidance for high-performance electron sources based on exponential-doping GaN NWAs *** field-assisted exponential-doping GaN NWAs cathode is expected to be verified by the experimental results in the future.

关键词： Exponential-doping GaN nanowire array Photocathode Field-assisted Quantum efficiency Electrons collection

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Static slip model of the m_w 9.0 Tohoku (Japan) earthquake:Results from joint inversion of terrestrial GPS data and seafloor GPS/acoustic data

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Chinese Science Bulletin 2012年第16期57卷 1990-1997页

作者： diao FaQi XIONG Xiong ZHENG Yong State Key Laboratory of Geodesy and Earth's Dyanmics Institute of Geodesy and GeophysicsChinese Academy of SciencesWuhan 430077China

Based on co-seismic displacements recorded by terrestrial GPS stations and seafloor GPS/acoustic stations, the static slip model of the 2011 mw 9.0 Tohoku earthquake was determined by inverting the data using a layered earth model. According to a priori information, the rupture surface was modeled with a geometry that is close to the actual rupture, in which the fault dip angle increases with depth and the fault strike varies with the trend of the trench. As shown by the results inferred from the joint inversion, the "geodetic" moment is 3.68 × 10 22 Nm, corresponding to mw 9.01, and the maximum slip is positioned at a depth of 13.5 km with a slip magnitude of 45.8 m. Rupture asperities with slip exceeding 10 m are mainly distributed from 39.6 to 36.97°N, over a length of almost 240 km along the trench. The slip was mostly concentrated at depths shallower than 40 km, up-dip of the hypocenter. "Checkerboard" tests reveal that a joint inversion of multiple datasets can resolve the slip distribution better than an inversion with terrestrial GPS data only-especially when aiming to resolve slip at shallow depths. Thus, the joint inversion results obtained by this work may provide a more reliable slip model than the results of other studies that are only derived from terrestrial GPS data or seismic waveform data.

关键词： GPS数据联合反演滑移模型地震位移地面海底静态东北

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Bending fatigue behavior of thin Zr_(61)Ti_(2)Cu_(25)Al_(12)bulk metallic glass beams for compliant mechanisms application

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Journal of materials Science & Technology 2021年第30期89卷 1-15页

作者： diao-Feng Li Ya-Long Yang Yong Shen Jian Xu Institute of metal Research Chinese Academy of SciencesShenyang110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

In this work,bending fatigue behavior of thinner Zr_(61)Ti_(2)Cu_(25)Al_(12)(ZT1)BmG beams with thicknesses of 500μm and 100μm were investigated with three-point bending(3PB),to evaluate the reliability and safety of this potentially material used in compliant mechanisms under cyclic bending *** endurance limits(FELs)of ZT1 beams with thicknesses of 500μm and 100μm were determined to be 470 mPa,and~0.3 of its tensile *** life and FEL of ZT1 beams in bending are substantially independent of the beam thickness,in the scale from 500μm down to 100μ*** cracks of all ZT1 beams initiated at the extrinsic microvoids,either indirectly derived from surface scratches during mechanical polishing or originated from as-cast ***,fatigue crack propagation behavior is highly related to the magnitude of cyclic stress *** interrupted fatigue tests,larger proportion about 60-70%of fatigue life was spent on crack propagation under high stress level,while crack initiation occupied larger proportion about 80-85%under low stress *** medium stress level of about 590 mPa almost shared the crack-initiation life and crack-propagation *** addition,there are two crack deflection mechanisms during cracks steady propagation *** mechanism is crack deflection along the interacted shear bands ahead of crack-tip,the other one is crack"jump"from one shear band to another shear band at a certain *** two mechanisms alternate dominate the crack propagation process,generating typical staircase-like crack propagation *** endurance limits of ZT1 beams in the form of either stress amplitude or strain amplitude are superior to traditional candidate materials in the field of compliant mechanisms,showing that the better reliability and larger deflection deformation can be achieved for flexible members made by ZT1 BmG even under cyclic loading.

关键词： metallic glasses Bending fatigue Crack initiation Crack propagation Compliant mechanisms

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Antenna Selection and Power Allocation Design for 5G massive mImO Uplink Networks

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China Communications 2019年第4期16卷 1-15页

作者： Hongyuan Gao Yumeng Su Shibo Zhang ming diao College of Information and Communication Engineering Harbin Engineering University

massive mImO is one of the key technologies in future 5G communications which can satisfy the requirement of high speed and large capacity. This paper considers antenna selection and power allocation design to promote energy conservation then provide good quality of service(QoS) for the whole massive mImO uplink network. Unlike previous related works, hardware impairment, transmission efficiency, and energy consumption at the circuit and antennas are involved in massive mImO networks. In order to ensure the QoS, we consider the minimum rate constraint for each user and the system, which increases the complexity of power allocation problem for maximizing energy and spectral efficiency in massive mImO system. To this end, a quantum-inspired social emotional optimization(QSEO) algorithm is proposed to obtain the optimal power control strategy in massive mImO uplink networks. Simulation results assess the great advantages of QSEO which previous strategies do not have.

关键词： 5G massive mImO antenna selection power allocation quantum-inspiredsocial emotional optimization

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Experimental study on the new type of electrical storage heater based on flat micro-heat pipe arrays

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Science China(Technological Sciences) 2018年第2期61卷 219-231页

作者： wang zeyu diao yanhua zhao yaohua liang lin wang tengyue beijing key laboratory of green built environment and efficient technology beijing university of technologyBeijing 100124China beijing advanced innovation center for future internet technology Beijing 100124China

A new type of electrical storage heater that utilizes latent heat storage and flat micro-heat pipe arrays （FmHPAs） was developed. The thermal characteristics of the heater were tested through experimentation. The structure and operating principle of the storage heater were expounded. Three rows of FmHPAs were applied （three rows with five assemblies each） with a mass of 28 kg of phase change material （PCm） in the heat storage tank. Electric power was supplied to the PCm in the range of 0.2-2.04 kW, and air was used as heat transfer fluid, with the volume flow rate ranging from 40-120 m3/h. The inlet temperature was in the range of 15-24~C. The effects of heating power, air volume flow rate, and inlet temperature were investigated. The electrical storage heater exhibited efficiencies of 97% and 87% with 1.98 and 1.30 kW of power during charging and discharging, respectively. Application of the proposed storage heater can transfer electricity from peak periods to off-peak periods, and the excess energy generated by wind farms can be stored as heat and released when needed. Good economic and environmental benefits can be obtained.

关键词： flat micro-heat pipe latent heat storage electrical storage heater peak load shifting wind power utilization

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