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An Enhanced Multiview Transformer for Population Density Estimation Using Cellular Mobility Data in Smart City

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Computers, Materials & Continua 2024年第4期79卷 161-182页

作者： yu zhou Bosong lin Siqi Hu Dandan yu College of Computer Science and Software Engineering Shenzhen UniversityShenzhen518060China College of Management Shenzhen UniversityShenzhen518060China Information Center The First Affiliated Hospital of Dalian Medical UniversityDalian116011China

This paper addresses the problem of predicting population density leveraging cellular station *** wireless communication devices are commonly used,cellular station data has become integral for estimating population figures and studying their movement,thereby implying significant contributions to urban ***,existing research grapples with issues pertinent to preprocessing base station data and the modeling of population *** address this,we propose methodologies for preprocessing cellular station data to eliminate any irregular or redundant *** preprocessing reveals a distinct cyclical characteristic and high-frequency variation in population ***,we devise a multi-view enhancement model grounded on the Transformer(MVformer),targeting the improvement of the accuracy of extended time-series population *** experiments,conducted on the above-mentioned population dataset using four alternate Transformer-based models,indicate that our proposedMVformer model enhances prediction accuracy by approximately 30%for both univariate and multivariate time-series prediction *** performance of this model in tasks pertaining to population prediction exhibits commendable results.

关键词： Population density estimation smart city transformer multiview learning

FINITE DIFFERENCE METHOD WITH NONUNIFORM MESHES FOR QUASIlinEAR PARABOLIC SYSTEMS

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Journal of Computational Mathematics 1997年第4期15卷 289-310页

作者： yu-lin zhou (Labomtory of Computational Physics, Center of Nonlinear Studies, Institute of Applied Physics and Computational Mathematics, Beijing, China) 北京应用物理和计算数学所北京

The analysis of the finite difference schemes with nonuniform meshes for the problems of partial differential equations is extremely rare even for very simple problems and even for the method of fully heuristic character. In the present work the boundary value problem for quasilinear parabolic system is solved by the finite difference method with nonuniform meshes. By using of the interpolation formulas for the spaces of discrete functions with unequal meshsteps and the method of a priori estimation for the discrete solutions of finite difference schemes with nonuniform meshes, the absolute and relative convergence of the discrete solutions of the finite defference scheme are proved. The limiting vector function is just the unique generalized solution of the original problem for the parabolic system.

关键词： Boundary value problems Convergence of numerical methods Estimation Heuristic methods Interpolation Partial differential equations

Stiffness Analysis of Spherical Parallel Mechanism U_(P+R) with 2-DOF

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 41-47页

作者： yu-lin zhou Long Yang Bo Li Da-Xing Zeng Feng Gao School of Mechanical Engineering Yanshan University XCMG Xuzhou Truck-Mounted Crane Co. Ltd. State Key Laboratory of Mechanical System and Vibration Shanghai Jiaotong University

As one of the typical less-mobility parallel mechanisms, the spherical parallel mechanism Up.s with two degrees of freedom （2-DOF） possess high order overconstraints, and the calculation of its stiffness is partly different with general parallel mechanisms owing to the bars in each branch are assumed to be arc-shaped. By means of small deformation superposition principle, the relationship between the angle displacement and line displacement of moving platform and the forces acted on the branches were derived out. Based on the results of static analysis, the relationship between the applied force, the line displacement and the angle displacement of the mechanism was set up. And then the stiffness matrix was obtained. The six principal stiffness of the mechanism and the corresponding directions were achieved by the orthogonal transformation. The numerical calculation was performed and the results showed that the principal stiffness and directions are varied with the pose-position of the mechanism, and the principal stiffness is gradually enlarged when it is far away from the anigin. In addition, the torsion stiffness is much greater and the line deformation stiffness is smaller, the difference between the two parts is huge. The research content of this paper supplies the theoretical foundation for the further engineering design and application of the spherical parallel mechanism.

关键词： spherical parallel mechanism static stiffness orthogonal transformation line displacement angle

A low-profile metamaterial absorber with ultrawideband reflectionless and wide-angular stability

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Defence Technology（防务技术） 2024年第4期34卷 258-268页

作者： Feihong lin Zhongming Yan Ping Wang yu Wang Hongcheng zhou Haoran Lu School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China Key Laboratory of Magnetic Suspension Technology and Maglev Vehicle Ministry of EducationChengdu 610031China China Academy of Launch Vehicle Technology Beijing 100076China

An ultrawideband reflectionless metamaterial absorber(MA)is proposed by replacing the metallic ground with the complementary split-ring resonator(CSRR)*** proposed MA exhibits-10 d B reflectivity spectrum from 1 GHz to 20 GHz,which maintains more than 90%absorption from 1.5 GHz to20 ***,it achieves angle stability for TE and TM polarization at oblique incident angles up to 40°and 65°,*** achieve broadband absorption spectrum,we have adopted a single-layer high-impedance surface(HIS)loaded with a double-layer magnetic material(MM)*** further realize the RCS reduction into a lower frequency range,we have employed the scattering cancellation technology into the traditional metallic ***,we have fabricated a sample exhibiting the 10 d B RCS reduction from 1 GHz to 20 GHz with a thickness of 10 *** and simulation results confirm that the proposed MA exhibits excellent comprehensive performance,making it suitable for many practical applications.

关键词： Metamaterial absorber(MA) Magnetic material(MM) High-impedance surface(HIS) Scattering cancellation technology Ultrawideband Wide-angular stable

Genetic counseling, prenatal screening and diagnosis of Down syndrome in the second trimester in women of advanced maternal age： a prospective study

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Chinese Medical Journal 2013年第11期126卷 2007-2010页

作者： QI Qing-wei JIANG yu-lin zhou Xi-ya LIU Jun-tao YIN Jie BIAN Xu-ming Department of Obstetrics and Gynecology Chinese Academy ofMedical Science Peking Union Medical College Peking UnionMedical College Hospital Beijing 100730 China

Background The incidence of autosomal trisomy in livebirths is strongly dependent on maternal age. Special consideration is given to the provision of prenatal screening and cytogenetic testing to women of advanced maternal age （AMA）. The aim of this study was to evaluate the effectiveness of second trimester prenatal screening and amniocentesis for Down syndrome （DS） and compare the trends of choice of screening and amniocentesis among AMA women. Methods A total of 5404 AMA patients with natural singleton pregnancy were recruited for this prospective study from January 2008 to December 2010. The gestational weeks were from 15 weeks to 20~6 weeks. The patients referred were grouped into a screening group （2107 cases） and an amniocentesis group （3297 cases） by their own decision. The prevalence of DS was compared between the two groups by chi-square test. Choice rates for each maternal age with trends were compared by regression analysis. Results There were 18 cases of fetal DS detected in the screening group with a prevalence of 8.54%o （18/2107）. Twenty- five cases of fetal DS were diagnosed in the amniocentesis group with a prevalence of 7,58%0 （25/3297）. No statistical difference was observed in the prevalence of DS between the screening and amniocentesis group （P=0.928）. The invasive testing rate for DS in the amniocentesis group was 5.54 times higher than that of the screening group （1/131.88 vs. 1/23.78）. With the increase of the maternal age, the choice of amniocentesis increased while the choice of the screening showed an opposite trend. The choice of the AMA women between the screening and amniocentesis was significantly age relevant （P=0.012）. Conclusions The second trimester serum screening age alone to screen for DS. We suggest educating screening and amniocentesis options. in combination with maternal age was more effective than maternal the patients by recommending AMA women be informed of both

关键词： genetic counseling advanced maternal age Down syndrome prenatal screening genetic amniocentesis second trimester

Lipid metabolism, amino acid metabolism, and prostate cancer: a crucial metabolic journey

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Asian Journal of Andrology 2024年第2期26卷 123-134页

作者： lin Chen yu-Xin Xu yuan-Shuo Wang Jian-Liang zhou School of Pharmacy Hangzhou Normal UniversityHangzhou 311121China Key Laboratory of Elemene Class Anti-Cancer Chinese Medicines Collaborative Innovation Center of Traditional Chinese Medicines of Zhejiang Province Hangzhou Normal UniversityHangzhou 311121China School of Pharmacy Guangxi Medical UniversityNanning530021China

Prostate cancer(PCa)is one of the most common malignancies in males worldwide,and its development and progression involve the regulation of multiple metabolic *** in lipid metabolism affect the proliferation and metastatic capabilities of PCa *** cells increase lipid synthesis and regulate fatty acid oxidation to meet their growth and energy ***,changes occur in amino acid metabolism in *** cells exhibit an increased demand for specific amino acids,and they regulate amino acid transport and metabolic pathways to fulfill their proliferation and survival *** changes are closely associated with disease progression and treatment response in PCa ***,a comprehensive investigation of the metabolic characteristics of PCa is expected to offer novel insights and approaches for the early diagnosis and treatment of this disease.

关键词： amino acid metabolism lipid metabolism metabolic pathways prostate cancer treatment strategies

Polymerase chain reaction-based assays facilitate the breeding and study of mouse models of Klinefelter syndrome

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Asian Journal of Andrology 2022年第1期24卷 102-108页

作者： Hai-Xia Zhang yu-lin zhou Wen-Yan Xu Xiao-Lu Chen Jia-Yang Jiang Xiao-Man zhou Zeng-Ge Wang Rong-Qin Ke Qi-Wei Guo United Diagnostic and Research Center for Clinical Genetics Women and Children’s HospitalSchool of Medicine and School of Public HealthXiamen UniversityXiamen 361102China School of Biomedical Sciences and School of Medicine Huaqiao UniversityQuanzhou 362021China Beijing Children’s Hospital Capital Medical UniversityBeijing 100045China

Klinefelter syndrome(KS)is one of the most frequent genetic abnormalities and the leading genetic cause of nonobstructive *** breeding and study of KS mouse models are essential to advancing our knowledge of the underlying pathological *** and fluorescence in situ hybridization are reliable methods for identifying chromosomal ***,technical issues associated with these methods can decrease the efficiency of breeding KS mouse models and limit studies that require rapid identification of target *** overcome these limitations,we developed three polymerase chain reaction-based assays to measure specific genetic information,including presence or absence of the sex determining region of chromosome Y(Sry),copy number of amelogenin,X-linked(Amelx),and inactive X specific transcripts(Xist)*** a combined analysis of the assay results,we can infer the karyotype of target *** confirmed the utility of our assays with the successful generation of KS mouse *** assays are rapid,inexpensive,high capacity,easy to perform,and only require small sample ***,they facilitate the breeding and study of KS mouse models and help advance our knowledge of the pathological mechanism underlying KS.

关键词： 40,XXY^(*)mouse 41,XXY mouse Klinefelter syndrome mouse model

Lanthanum promoting bone formation by regulating osteogenesis,osteoclastogenesis and angiogenesis

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Journal of Rare Earths 2024年第3期42卷 621-628,I0007页

作者： Dandan Zou Runlian lin yu Han Juan Jia Guoqiang zhou Haisong Zhang Kun Ge Hebei Key Laboratory of Chronic Kidney Diseases and Bone Metabolism Affiliated Hospital of Hebei UniversityBaoding071000China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei UniversityBaoding071002China

With lanthanum(La) in agriculture, medicine, and the chemical industry, La shows accumulation in the body, especially in the bone, because of its similar structure to calcium. Moreover, La has a direct role in bone formation regulating osteoblasts and osteoclasts. Nevertheless, bone formation is complex under the regulation of osteogenesis, osteoclastogenesis, and angiogenesis in the bone microenvironment. It is difficult to comprehensively understand the regulation of bone homeostasis from a single kind of ***, some bone microenvironment-related cells and mouse calvaria culture models were used to study the regulatory effect of La-based compound-lanthanum nitrate(La(NO_(3))_(3)) on bone ***(NO_(3))_(3) has good biological safety, and the osteogenic differentiation is significantly increased under La(NO_(3))_(3) treatment for bone marrow mesenchymal stem cells(BMMSC). In contrast, the differentiation,maturation, and bone erosion ability of osteoclasts are significantly decreased. Meanwhile, the angiogenesis ability of human umbilical vein endothelial cells(HUVEC) is significantly promoted when treated with La(NO_(3))_(3). Furthermore, bone metabolism and angiogenesis are improved under La(NO_(3))_(3) treatment in the calvaria ex vivo culture model and BMMSC-HUVEC co-culture system. These results suggest that La has the beneficial effect of promoting bone metabolism and improving bone formation in the bone microenvironment.

关键词： Lanthanum Bone microenvironment Osteogenic differentiation Angiogenesis Rare earths

Deciphering the high-carbonization-temperature triggered enzymatic activity of wool-derived N,S-co-doped carbon nanosheets

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Chinese Chemical Letters 2024年第3期35卷 182-188页

作者： Jiachen Zhao Deshuai yu Jianmin Chen Shihao lin Yonghua Tang Chaoyu Fan Dongfang zhou Youhui lin Department of Physics Research Institute for Biomimetics and Soft MatterFujian Provincial Key Laboratory for Soft Functional Materials ResearchXiamen UniversityXiamen 361005China School of Pharmacy and Medical Technology Putian UniversityPutian 351100China Key Laboratory of Mental Health of the Ministry of Education NMPA Key Laboratory for Research and Evaluation of Drug Metabolism&Guangdong Provincial Key Laboratory of New Drug ScreeningSchool of Pharmaceutical SciencesSouthern Medical UniversityGuangzhou 510515China Key Laboratory of Pharmaceutical Analysis and Laboratory Medicine(Putian University) Fujian Province UniversityPutian 351100China

It is well-established that high carbonization temperature will trigger the enzyme-like activity of carbon-based ***,the catalytic mechanism is still ambiguous,which hinders the further rational design of nanomaterials as enzyme ***,N,S-rich carbonized wool nanosheets(CWs)were synthesized at different pyrolysis *** expected,only CWs treated with high-temperature possess intrinsic oxidase-and peroxidase-like ***,density functional theory(DFT)calculations demonstrate that graphitic nitrogen and the co-existence of nitrogen and sulfur in the carbon matrix serve as the active sites for the enzyme-like *** importantly,combining theoretical calculations and experimental observations,the high-temperature triggered catalytic mechanism can be ascribed to the fact that an appropriate high-temperature maximizes the graphitization degree to a certain extent,at which most of the catalytic active sites are well retained rather than ***,coupling with excellent photothermal conversion efficiency and catalytic performance,CWs can be applied to photothermal-catalytic cancer therapy under near-infrared region(NIR)light *** believe this work will contribute to understanding the catalytic mechanism of carbon-based nanozymes and promote the development of new biomedical and pharmaceutical applications.

关键词： Carbon-based nanozyme Catalytic mechanism Density functional theory High-temperature carbonization