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Applied Mathematics(A Journal of Chinese Universities) 2022年第2期37卷 228-245页

作者： wei mei LI Qiang Department of Mathematics Northwest Normal UniversityLanzhou 730070China Department of Mathematics Shanxi Normal UniversityLinfen 041000China School of Mathematical Sciences Qufu Normal UniversityQufu 273165China

In this paper, we investigate a class of abstract neutral fractional delayed evolution equation in the fractional power space. With the aid of the analytic semigroup theories and some fixed point theorems, we establish the existence and uniqueness of the S-asymptotically periodic α-mild solutions. The linear part generates a compact and exponentially stable analytic semigroup and the nonlinear parts satisfy some conditions with respect to the fractional power norm of the linear part, which greatly improve and generalize the relevant results of existing literatures.

关键词： neutral fractional evolution equations S-asymptotically periodic problem α-mild solutions fractional power space analytic semigroup

Upper bounds for eigenvalues of Cauchy-Hankel tensors

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Frontiers of Mathematics in China 2021年第4期16卷 1023-1041页

作者： wei mei Qingzhi YANG School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071China School of Mathematics and Statistics Kashi UniversityKashi 844006China

We present upper bounds of eigenvalues for finite and infinite dimensional Cauchy-Hankel *** is proved that an m-order infinite dimensional Canchy-Hankel tensor defines a bounded and positively(m-1)-homogeneous operat... 详细信息

关键词： Cauchy-Hankel tensor eigenvalues upper bound M-positive definite

A first-principles study of displacive β to ω transition in Ti-V alloys

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Progress in Natural Science:Materials International 2017年第6期27卷 703-708页

作者： wei mei Jian Sun Yufeng Wen Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming School of Materials Science and Engineering Shanghai Jiao Tong University School of Mathematical Sciences & Physics Jinggangshan University

The ground state properties of β and ω phases in Ti-(0–30 at%)V alloys were calculated, and subsequently thermodynamics and energy barriers of the displacive β to ω transition were investigated by first-principles. The results show that the lattice parameters of β and ω phases decreases with increasing V content in Ti-V alloys. The principal lattice strains for the β to ω transition are highly compositional dependent, and the volume variation decreases with increasing V content. The mechanical stability of the ω phase increases initially at the V content around 10 at% and then decreases with increasing V content. Based on the quasiharmonic Debye model, a metastable diffusionless phase diagram has been established, showing that the ω phase is thermodynamically more stable than the β phase at room temperature, anticipating a spontaneous transition from β to ω phases in Ti-V alloys. The calculations of energy pathways indicate that there is an energy barrier during the displacive βto ω transition in Ti-V alloys at temperatures from 100 to 500 K, but not at 0 K.

关键词： Elastic property Phase transition Ti-V alloys First-principles

Recent development in multizonal scaffolds for osteochondral regeneration

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Bioactive Materials 2023年第7期25卷 122-159页

作者： Le Yu Sacha Cavelier Brett Hannon mei wei Department of Chemical and Biomolecular Engineering Ohio UniversityAthensOH45701USA Biomedical Engineering Program Ohio UniversityAthensOH45701USA Department of Mechanical Engineering Ohio UniversityAthensOH45701USA

Osteochondral(OC)repair is an extremely challenging topic due to the complex biphasic structure and poor intrinsic regenerative capability of natural osteochondral *** contrast to the current surgical approaches which yield only short-term relief of symptoms,tissue engineering strategy has been shown more promising outcomes in treating OC defects since its emergence in the *** particular,the use of multizonal scaffolds(MZSs)that mimic the gradient transitions,from cartilage surface to the subchondral bone with either continuous or discontinuous compositions,structures,and properties of natural OC tissue,has been gaining momentum in recent *** the latest developments in the field,this review offers a comprehensive summary of recent advances,current hurdles,and future perspectives of OC repair,particularly the use of MZSs including bilayered,trilayered,multilayered,and gradient scaffolds,by bringing together onerous demands of architecture designs,material selections,manufacturing techniques as well as the choices of growth factors and cells,each of which possesses its unique challenges and opportunities.

关键词： Multizonal scaffolds Osteochondral regeneration Fabrication Cells Growth factors

Uniform Invariance Principle of Discontinuous Systems with Parameter Variation

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Acta Mathematicae Applicatae Sinica 2013年第4期29卷 717-724页

作者： Ju-mei wei Rui MA Xiao-wu MU School of Mathematics and Statistics Zhengzhou University

An extension of the invariance principle for a class of discontinuous righthand sides systems with parameter variation in the Filippov sense is proposed. This extension allows the derivative of an auxiliary function V, also called a Lyapunov-like function, along the solutions of the discontinuous system to be positive on some sets. The uniform estimates of attractors and basin of attractions with respect to parameters are also obtained. To this end, we use locally Lipschitz continuous and regular Lyapunov functions, as well as Filippov theory. The obtained results settled in the general context of differential inclusions, and through a uniform version of the LaSalle invariance principle. An illustrative example shows the potential of the theoretical results in providing information on the asymptotic behavior of discontinuous systems.

关键词： invariance principle Lyapunov functions discontinuous systems

Global analysis of sensitivity of bioretention cell design elements to hydrologic performance

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Water Science and Engineering 2011年第3期4卷 246-257页

作者： Yan-wei SUN Xiao-mei wei Christine A. POMEROY College of Water Resources and Architectural Engineering Northwest A ＆ F University Yangling 712100 P. R. China Department of Civil and Environmental Engineering University of Utah Salt Lake City UT 84112 USA

Analysis of sensitivity of bioretention cell design elements to their hydrologic performances is meaningful in offering theoretical guidelines for proper design. Hydrologic performance of bioretention cells was facilitated with consideration of four metrics： the overflow ratio, groundwater recharge ratio, ponding time, and runoff coefficients. The storm water management model （SWMM） and the bioretention infiltration model RECARGA were applied to generating runoff and outflow time series for calculation of hydrologic performance metrics. Using a parking lot to build a bioretention cell, as an example, the Morris method was used to conduct global sensitivity analysis for two groups of bioretention samples, one without underdrain and the other with underdrain. Results show that the surface area is the most sensitive element to most of the hydrologic metrics, while the gravel depth is the least sensitive element whether bioretention cells are installed with underdrain or not. The saturated infiltration rate of planting soil and the saturated infiltration rate of native soil are the other two most sensitive elements for bioretention cells without underdrain, while the saturated infiltration rate of native soil and underdrain size are the two most sensitive design elements for bioretention cells with underdrain.

关键词： bioretention hydrologic performance global sensitivity analysis Morris method

Venetoclax in combination with chidamide and dexamethasone in relapsed/refractory primary plasma cell leukemia without t(11;14):A case report

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World Journal of Clinical Cases 2021年第5期9卷 1175-1183页

作者： Yang Yang Li-Juan Fu Chun-mei Chen mei-wei Hu Department of Hematology The Second Affiliated Hospital of Zhejiang Chinese Medical UniversityHangzhou 310014Zhejiang ProvinceChina

BACKGROUND Conventional therapies for primary plasma cell leukemia(pPCL)are usually ineffective,with a short remission time with the use of multiple myeloma medications,showing aggressiveness of pPCL.B-cell lymphoma-2 inhibitor venetoclax is usually used for relapsed/refractory multiple myeloma(RRMM)with t(11;14).There are very few studies published on the use of venetoclax in pPCL without t(11;14).Similarly,histone deacetylase inhibitors are considered effective for the treatment of RRMM,but there are no reports on their use in *** SUMMARY A 57-year-old woman with severe anemia,thrombocytopenia,multiple bone destruction,impaired renal function,and 42.7%of peripheral plasma cells is *** multiple chemotherapy regimens and chimeric antigen receptor Tcell treatment,the disease progressed *** patient had very good partial response and was maintained for a long time on venetoclax in combination with chidamide and dexamethasone *** The success of venetoclax-chidamide-dexamethasone combination therapy in achieving a very good partial response suggested that it can be used for refractory/relapsed pPCL patients who have been exhausted with the use of various drug combinations and had poor survival outcomes.

关键词： Relapsed/refractory Primary plasma cell leukemia Venetoclax Chidamide Very good partial response Case report

Research on Modified Shifting Balance Genetic Algorithms

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Journal of China University of Mining and Technology 2007年第2期17卷 188-192页

作者： MA Hong-mei GONG Dun-wei School of Information and Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

The increasing overlap of core and colony populations during the anaphase of evolution may limit the performance of shifting balance genetic algorithms. To decrease such overlapping,so as to increase the local search capability of the core population,the sub-space method was used to generate uniformly distributed initial colony populations over the decision variable space. The core population was also dynamically divided,making simultaneous searching in several local spaces possible. The algorithm proposed in this paper was compared to the original one by searching for the optimum of a complicated multi-modal function. The results indicate that the solutions obtained by the modified algorithm are better than those of the original algorithm.

关键词： genetic algorithms shifting balance genetic algorithms small spaces dynamic partition multi-modal function

Real-time Ultrasound-guided Spinal Anesthesia Using a New Paramedian Transverse Approach

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Current Medical Science 2018年第5期38卷 910-913页

作者： Yong LIU wei QIAN Xi-jian KE wei mei Department of Anesthesiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Ultrasound-guided spinal anesthesia is an attracting and advanced technique. We developed a new paramedian transverse approach for real-time ultrasound-guided spinal *** this approach,the block can be performed with the dominant hand whether in right or left lateral decubitus or sitting *** preliminary experience in 42 orthopedic and obstetric patients showed it could achieve high first pass success rate with acceptable procedure *** effectiveness and safety of this approach need further investigation by comparing it with blind technique and other ultrasound-guided techniques with well-designed randomized controlled trials.

关键词： anesthetic techniques spinal anesthesia subarachnoid ultrasound

Magnetic and Optical Properties of the TiO_2-Co-TiO_2 Composite Films Grown by Magnetron Sputtering

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Chinese Journal of Aeronautics 2007年第2期20卷 162-167页

作者： LIU Fa-min DING Peng SHI wei-mei WANG Tian-min Department of Physics School of Sciences Beijing University of Aeronautics and Astronautics Beijing 100083 China

The TiO2-Co-TiO2 sandwich films were successfully grown on glass and silicon substrata making alternate use of radio frequency reactive magnetron sputtering and direct current magnetron sputtering. The structures and properties of these films were identified with X-ray diffraction （XRD）, Raman spectra and X-ray photoemission spectra （XPS）. It is shown that the sandwich film consists of two anatase TiO2 films with an embedded Co nano-film. The fact that, when the Co nano-film thickens, varied red shifts appear in optical absorption spectra may well be explained by the quantum confinement and tunnel effects. As for magnetic properties, the saturation magnetization, remnant magnetic induction and coercivity vary with the thickness of the Co nano-films. Moreover, the Co nano-film has a critical thickness of about 8.6 mn, which makes the coercivity of the composite film reach the maximum of about 1413 Oe.

关键词： TiO2-Co-TiO2 sandwich films surface structure and properties optical and magnetic properties