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Criteria air pollutants and hospitalizations of a wide spectrum of cardiovascular diseases: A nationwide case-crossover study in China

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Eco-Environment & Health 2022年第4期1卷 204-211页

作者： Cong Liu Renjie Chen Xia Meng weidong Wang Jian Lei Yixiang Zhu Lu Zhou Haidong Kan Jianwei Xuan School of Public Health Shanghai Institute of Infectious Disease and BiosecurityKey Lab of Public Health Safety of the Ministry of Education and NHC Key Lab of Health Technology AssessmentFudan UniversityShanghai 200032China Children’s Hospital of Fudan University National Center for Children’s HealthShanghai 201102China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Health Economic Research Institute School of PharmacySun Yat-Shen UniversityGuangzhou 510275China

Few national studies have systemically examined the effects of criteria air pollutants on cardiovascular *** study aimed to investigate the associations between all criteria air pollutants and hospitalization of causespecific cardiovascular diseases(CVD)in *** obtained data on CVD hospitalization events of four major categories and 12 specific diseases from 153 hospitals distributed in 20 provincial-level regions from 2013 to *** adopted a time-stratified case-crossover study design using individual cases to capture the effect of short-term exposure to six criteria air pollutants on CVD hospitalizations,using conditional logistic regression *** than 1.1 million CVD hospitalization events were *** lag pattern exploration demonstrated the largest effect for six air pollutants on lag 0–1 ***_(2.5),PM_(10),NO_(2),and CO were significantly associated with increased hospitalization from ischemic heart diseases,cerebrovascular diseases,other heart diseases,and five specific causes of *** effect estimates of NO_(2)were the most robust when adjusting for *** concentration-response curves were positive and linear for most pollutant–endpoint pairs(except for O_(3)),and these positive associations remained even below the 24-h levels recommended by WHO Air Quality Guidelines and China Air Quality *** nationwide case-crossover study in China demonstrated that short-term exposure to multiple ambient air pollutants may significantly increase the risk of cause-specific CVD hospitalizations even under the most stringent air quality regulations,striking an alert for potential CVD patients against these environmental risk factors.

关键词： Criteria air pollutants Hospitalization Cardiovascular disease Cause-specific Case-crossover study

Laser powder bed fusion of a Ni3Al-based intermetallic alloy with tailored microstructure and superior mechanical performance

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Advanced Powder Materials

Advanced Powder Materials 2024年第1期3卷 90-101页

作者： Mingyu Liu Jiang Wang Tao Hu Songzhe Xu Sansan Shuai weidong Xuan Shuo Yin Chaoyue Chen Zhongming Ren State Key Laboratory of Advanced Special Steels School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Parsons Building Department of MechanicalManufacturing and Biomedical EngineeringTrinity College DublinThe University of DublinDublinIreland College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China

Ni3Al-based alloys are excellent candidates for the structural materials used for turbine engines due to their excellent high-temperature *** study aims at laser powder bed fusion and post-hot isostatic pressing(HIP)treatment of Ni3Al-based IC^(-2)21 M alloy with a highγ0 volume *** as-built samples exhibits unavoidable solidification cracking and ductility dip cracking,and the laser parameter optimization can reduce the crack density to 1.34 mm/mm^(2).Transmission electron microscope(TEM)analysis reveals ultra-fine nanoscaleγ0 phases in the as-built samples due to the high cooling rate during rapid *** HIP treatment,a fully dense structure without cracking defects is achieved,which exhibits an equiaxed structure with grain size~120-180μm and irregularly shapedγ0 precipitates~1-3μm with a prominently high fraction of 86%.The room-temperature tensile test of as-built samples shows a high ultimate tensile strength(σUTS)of 1039.7 MPa and low fracture elongation of 6.4%.After HIP treatment,a significant improvement in ductility(15.7%)and a slight loss of strength(σUTS of 831.7 MPa)are obtained by eliminating the crack *** the as-built and HIP samples exhibit retained highσUTS values of 589.8 MPa and 786.2 MPa,respectively,at *** HIP samples exhibita slight decrease in ductility to~12.9%,indicating excellent high-temperature mechanical ***,the abnormal increase in strength and decrease in ductility suggest the critical role of a highγ0 fraction in cracking *** intrinsic heat treatment during repeating thermal cycles can induce brittleness and trigger cracking initiation in the heat-affected zone with notable deteriorating *** results indicate that the combination of LPBF and HIP can effectively reduce the crack density and enhance the mechanical properties of Ni_(3)Al-based alloy,making it a promising material for high-temperature applications.

关键词： Laser powder bed fusion Ni3Al-Based alloy Hot isostatic pressing Solidification cracking High-temperature tensile performance

HIGH RESOLUTION RANGE PROFILE FORMATION BASED ON LFM SIGNAL FUSION OF MULTIPLE RADARS

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Journal of Electronics(China) 2007年第1期24卷 75-82页

作者： Wang Cheng Hu weidong Du Xiaoyong Yu Wenxian ATR Key Lab National University of Defense Technology Changsha 410073 China

This paper presents a new method of High Resolution Range (HRR) profile formation based on Linear Frequency Modulation (LFM) signal fusion of multiple radars with multiple frequency bands. The principle of the multiple radars signal fusion improving the range resolution is analyzed. With the analysis of return signals received by two radars,it is derived that the phase difference between the echoes varies almost linearly with respect to the frequency if the distance between two radars is neg-ligible compared with the radar observation distance. To compensate the phase difference,an en-tropy-minimization principle based compensation algorithm is proposed. During the fusion process,the B-splines interpolation method is applied to resample the signals for Fourier transform imaging. The theoretical analysis and simulations results show the proposed method can effectively increase signal bandwidth and provide a high resolution range profile.

关键词： Linear Frequency Modulation (LFM) Inverse Synthetic Aperture Radar (ISAR) Signal fusion High Resolution Range (HRR) profile

The velocity structure of the Yinggehai Basin and its hydrocarbon implication

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Chinese Science Bulletin 1998年第24期43卷 2047-2054页

作者： Kanyuan Xia Di Zhou Daquan Su E. Flueh Sanyu Ye Hanyi He weidong Chen Yuhong Xie Guixian Wang Saijun Liu et al. Chinese Acad Sci S China Sea Inst Oceanol Guangzhou 510301 Peoples R China Univ Kiel Res Ctr Marine Geosci D-24098 Kiel Germany China Offshore Oil Nanhai W Corp Zhanjiang 524057 Peoples R China Seismol Bur Hainan Prov Haikou 570003 Peoples R China Seismol Bur Fujian Prov Fuzhou 350003 Peoples R China

Two profiles of refraction and wide_angle reflection were completed in the Yinggehai Basin using ocean bottom hydrophones (OBHs) as receiver. These profiles reveal a low velocity layer (LVL) to the west of No. 1 Fault in the basin, with velocity of 3.0-3.5 km/s. Its upper interface lies at 3.5 km below the sea bottom at the NE end of the profiles, and deepens southwestward to 4 6 km near the axis of the basin. It coincides with the top of a gas_bearing, high_pressure layer defined by well logging. This suggests that the LVL is a layer of less_compacted and gas_charged sediments. The lower interface of the LVL is about 9 km in depth. Sediments above the LVL have velocity varying from 2 0 to 4 1 km/s. The acoustic basement is found only east of No. 1 Fault, with velocity of 5 8-6 2 km/s. A NNW_SSE_running OBH seismic profile across the Xisha Trough was completed on the same cruise. Moho and other deep interfaces are clearly visible in the profile.

关键词： seismic refraction wide_angle reflection low velocity layer Yinggehai Basin.

Dielectric behaviors and relaxor characteristics in Bi_(0.5)Na_(0.5)TiO_(3)-BaTiO_(3) ceramics

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Journal of Advanced Dielectrics 2019年第5期9卷 57-64页

作者： Pei Chen Jun Wang weidong Zeng Changrong Zhou Yongsheng zhang Qingning Li Jiwen Xu Guohua Chen Changlai Yuan Guangxi Key Laboratory of Information Materials Guilin University of Electronic Technology Guilin Guangxi 541004P.R.China School of Material Science and Engineering Guilin University of Electronic Technology Guilin Guangxi 541004P.R.China

Microstructure and dielectric behaviors of heating/cooling and bias-field were investigated in lead-free ceramics(1-x)Bi_(0.5)Na_(0.5)TiO_(3)-xBaTiO_(3)(BNT-xBT,x=0,0.02,0.04,0.06,0.08 and 0.10).The relaxor characters and the Vogel–Fulcher law of frequency-dependent dielectric properties were *** dielectric anomalies with pronounced frequency dispersion at Td,a maximum dielectric with variable frequency-dispersion at Tm and a third Maxwell–Wagner-type relaxation over a wide temperature range in high-temperature region were *** significant dielectric thermal hysteresis,low barrier energy,high freezing temperature in heating process and the maximum dielectric tunability appeared in x=0.4 ceramic.

关键词： Bismuth sodium titanate dielectric relaxor Vogel-Fulcher law dielectric tunability

Heterogeneous Growth of ZnO Crystal on GaN/Al_(2)O_(3) Substrate

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Journal of Wuhan University of Technology(Materials Science) 2022年第4期37卷 576-579页

作者： FAN Long ZHONG Changjie WANG Xuemin CAO Linhong WANG Jin PENG Liping zhaN Zhiqiang XIONG Zhengwei WU weidong Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Southwest University of Science and Technology Mianyang 621010China

Hydrothermal(HT)ZnO substrates were usually used as seeds for the vapor growth of ZnO *** this work,ZnO bulk crystals were grown using the relatively low-cost GaN/AlOsubstrates as seeds by chemical vapor transport(CVT).With the increase of growth time,the dislocation densities in the crystal decreased from about 1×10^(6) to 6×10^(3) cm^(-2).The carrier concentration decreased from 1.24×10^(19) to 1.57×10^(17)cm^(-3),while the carrier mobility increased from 63.8 to 179 cm^(2)/(V·s).The optical transmittance in the VIS-NIR wavelength increased significantly in combination with the decreasing dislocation densities and impurity *** dislocation lines and related fast diffusion paths gradually decreased and disappeared in the late growth stage,and the crystal qualities were consequently *** experimental results show that the properties of as-grown ZnO crystals are comparable with bulk ZnO grown on the HT substrates to some *** GaN/Al_(2)O_(3) seeds may have a potential application value in the industrial production of ZnO single crystals.

关键词： ZnO single crystal GaN/Al_(2)O_(3)substrates chemical vapor transport heterogeneous growth

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社交网络中的概率支配集问题

华中科技大学学报（自然科学版） 2021年第2期49卷 85-88,107页

作者：钟昊陈卫东华南师范大学计算机学院广东广州510631

针对一种边权重取值范围为[0,1]的无向带权图,提出在社交网络中有实际应用的概率支配集概念。在图中寻找最少点数的概率支配集称为最小概率支配集问题。证明最小概率支配集问题是NP(非确定性多项式)难问题,表明不太可能存在多项式时间... 详细信息

针对一种边权重取值范围为[0,1]的无向带权图,提出在社交网络中有实际应用的概率支配集概念。在图中寻找最少点数的概率支配集称为最小概率支配集问题。证明最小概率支配集问题是NP(非确定性多项式)难问题,表明不太可能存在多项式时间复杂度的精确算法。基于次模函数提出了多项式时间复杂度的贪心近似算法,用于求解最小概率支配集问题,得出近似比结果。在真实的社交网络实例上进行实验,结果表明贪心算法所求的概率支配集中节点个数平均占总节点个数的14%~15%.

关键词：概率支配集社交网络 NP难次模函数近似算法

Expressions and clinical significance of CD147 and CK19 in hepatocellular carcinoma

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The Chinese-German Journal of Clinical Oncology 2012年第9期11卷 517-521页

作者： weidong Wang Ming zhao Yujun Li Department of Pathology The People's Hospital of Mengyin County Mengyin 276200 China Department of Oncology The People's Hospital of Mengyin County Mengyin 276200 China Department of Pathology The Affiliated Hospital of Qjngdao Medical College Qingdao 266071 China

Objective: The aim of this study was to investigate the expressions of CD147 and CK19 in hepatocellular car- cinoma (HCC) and their clinical significance. Methods: The expressions of CD147 and CK19 were determined by tissue microarray and immunohistochemistry (IHC) in 272 cases of HCC and 81 cases of adjacent tumorous tissue. Results: The positive expression of CD147 in HCC and adjacent tumorous tissue was 73.53% (200/272) and 13.58% (11/81) with signifi- cant difference (P 0.05). The positive expression of CK19 in HCC and adjacent tumorous tissue was 14.34% (39/272) and 0 (0/81) with significant difference (P 0.05). The positive expression of CD147 were closely correlated to the histological grade, clinical stage, tumor-free survival, diameter of tumor and embolus of cancer in aqueduct or portal vein; but not to the patients' sex, age, liver cirrhosis, AFP level, infection of HBV, lymph node metastasis, number of tumor, invasion liver involucrum and the micro-satellites (P > 0.05). The expression of CK19 in HCC were closely correlate to the tumor-free survival, histological grade, diameter of tumor, liver cirrhosis, micro-satellites, lymph node metastasis and clinical stage; but not to patients' sex, age, number of tumor, invasion liver involucrum, AFP level, infection of HBV and embolus of cancer in aqueduct or portal vein (P > 0.05). Among the patients of positive expression of CD147, the median replacing time and overall survival were 13 and 24 months, lower than 48 and 60 months in the patients of negative expression (P 0.05). Among the patients of positive expression of CK19, the median replacing time and overall survival were 7 and 13 months, lower than 31 and 42 months in the patients of negative expression (P 0.05). The expression of CD147 had no correlation with the expression of CK19 (r = 0.061, P = 0.317). Conclusion: The positive of CD147 and CK19 closely correlate with the clinical prognosis of HCC, it may indicate poor prognosis of HCC.

关键词： hepatocellular carcinoma (HCC) CD147 CK19 tissue microarray immunohistochemistry (IHC) prognosis

Enhanced multimodal luminescence and ultrahigh stability Eu^(3+)-doped CsPbBr_(3) glasses for X-ray detection and imaging

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Photonics Research 2021年第12期9卷 2369-2380页

作者： YAO TONG QIN WANG HENG YANG XIAOTING LIU ENROU MEI XIAOJUAN LIANG ZHIJUN zhaNG weidong XIANG College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

As an emerging scintillation material,metal halide perovskite(CsPbX3)has been deemed the most potentially valuable candidate in X-ray detection and medical ***,it is a continuing challenge to implement efficient radioluminescence(RL)with high radiation stability and moisture ***,the optimized luminescence properties and excellent uniformity of CsPbX3 glass are also key points for obtaining perfect X-ray ***,we have successfully precipitated Eu^(3+)-doped CsPbBr_(3)nanocrystals(NCs)with improved photoluminescence quantum yield(≈58.6%)because partial Eu^(3+)entered the perovskite lattice in a robust borosilicate glass matrix by in situ *** small amount of Eu addition made the lattice of NCs shrink and promoted uniform distribution of CsPbBr_(3)NCs in the glass,which effectively reduced the light scattering of the ***,multimodal RL intensity of the CsPbBr_(3)/CsPbBr_(3):xEu NCs glasses(CPB-0Eu/CPB-xEu)as a function of X-ray dose rate showed a superlinear relationship to the benefit of obtaining satisfactory X-ray ***,the outstanding radiation stability and water resistance of CPB-xEu were confirmed due to the protection of the robust glass ***,an X-ray imaging system using a CPB-xEu scintillator was constructed,and the spring in the opaque sample was legibly detected under the motivation of X-rays,indicating that CsPbX3 glasses possess extensive application prospects in terms of X-ray detection and medical imaging.

关键词： luminescence stability modal