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Applied Mathematics and Mechanics(english edition) 2021年第1期42卷 39-52页

作者： A.e.ABOUeLReGAL Department of Mathematics College of Science and ArtsJouf UniversityAl-Qurayyat 77423Saudi Arabia Department of Mathematics Faculty of ScienceMansoura UniversityMansoura 35516Egypt

A mathematical model linking thermoelasticity to photothermal experiments is proposed with the consideration of the photothermal *** system equations for coupled plasma,heat conduction with phase-lags(PLs),and motion equations are introduced and solved by using the Laplace transform *** photothermal,thermal,and elastic waves in a rotating solid cylinder of semiconductor material are analyzed with the proposed *** cylinder surface is constrained and subjected to a time-dependent pulse heat *** sensitivity of the physical fields for the angular velocity,PLs,and thermal vibration parameters is *** addition,the effects of the effective parameters on the physical quantities are graphically illustrated and discussed in detail.

关键词： photothermal phase-lag(PL) solid cylinder rotation semiconductor carrier concentration

Size-dependent thermoelastic initially stressed micro-beam due to a varying temperature in the light of the modified couple stress theory

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Applied Mathematics and Mechanics(english edition) 2020年第12期41卷 1805-1820页

The bending of the euler-Bernoulli micro-beam has been extensively modeled based on the modified couple stress(MCS)*** many models have been incorporated into the literature,there is still room for introducing an improved model in this *** this work,we investigate the thermoelastic vibration of a micro-beam exposed to a varying temperature due to the application of the initial stress employing the MCS theory and generalized *** MCS theory is used to investigate the material length scale *** the Laplace transform,the temperature,deflection,displacement,flexure moment,and stress field variables of the micro-beam are *** effects of the temperature pulse and couple stress on the field distributions of the micro-beam are obtained numerically and graphically *** numerical results indicate that the temperature pulse and couple stress have a significant effect on all field variables.

关键词： thermoelectricity micro-beam initial stress temperature pulse modified couple stress(MCS)theory

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose M.Santiago Samuel e.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.Miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain eAAT-1/GLAST eAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Collapse assessment of steel moment frames using endurance time method

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earthquake engineering and engineering Vibration 2015年第2期14卷 347-360页

作者： e.Rahimi H.e.estekanchi Department of Civil engineering Sharif University of Technology (SUT)

In endurance time(eT) method structures are subjected to a set of predesigned intensifying excitations. These excitations are produced in a way that their response spectrum, while complying with a specifi ed spectrum, intensifi es with time so they can be used approximately to simulate the average effects of several ground motions scaled to different intensities. In this paper applicability of the eT method for evaluating collapse potential of buildings is investigated. A set of four steel moment frames is used for collapse assessment. The process of using eT method in collapse evaluation is explained and the results are compared with incremental dynamic analysis(IDA) results. It is shown that although the computational effort using the eT method is much less than the IDA analysis, the results of both methods are consistent. Finally collapse fragility curves using eT and IDA methods are produced and it is shown that the probabilities of collapse in different hazard levels are also consistent.

关键词： endurance time method collapse analysis incrementa

Tracheoesophageal fistulas in coronavirus disease 2019 pandemic:A case report

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World Journal of Gastrointestinal endoscopy 2022年第10期14卷 628-635页

作者： Martin Alonso Gomez Zuleta Daniel Mauricio gallego Ospina Oscar Fernando Ruiz Department of Internal Medicine Gastroenterology unitUniversidad Nacional de ColombiaBogota 11321Colombia

BACKGROUND Tracheoesophageal fistulas(TeFs)can be described as a pathological communication between the trachea and the *** to their origin,they may be classified as benign or *** TeFs occur mostly as a consequence of prolonged mechanical ventilation,particularly among patients exposed to endotracheal cuff *** the severe acute respiratory syndrome coronavirus 2 virus pandemic,the amount of patients requiring prolonged ventilation rose,which in turn increased the incidence of *** SUMMARY We report the cases of 14 patients with different comorbidities such as being overweight,or having been diagnosed with diabetes mellitus or systemic *** most common symptoms on arrival were dyspnea and *** all cases,the diagnosis of TeFs was made through upper *** on the location and size of each fistula,either endoscopic or surgical treatment was *** patients were treated *** closure of the defect was achieved through over the scope clips in two patients,while three of them required endoscopic metal stenting.A hemoclip was used to successfully treat one patient,and it was used temporarily for another patient pended *** treatment was performed in patients with failed endoscopic management,leading to successful defect *** patients died before receiving corrective treatment and four died later on in their clinical course due to infectious *** The incidence of TeFs increased during the coronavirus disease 2019 pandemic(from 0.5%to 1.5%).We believe that endoscopic treatment should be considered as an option for this group of patients,since evidence reported in the literature is still a growing ***,we propose an algorithm to lead intervention in patients presenting with TeFs due to prolonged intubation.

关键词： Tracheoesophageal fistula COVID-19 endoscopy therapy Gastroenterology therapy Case report

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四氯化碳诱导的肝损伤对大鼠免疫机能的影响

中国病理生理杂志 2000年第7期16卷 665-666页

作者：王丙云陈龙毛鑫智 J.Gonzalez-gallego 佛山科技学院动物医学系广东南海528231 南京师范大学生命学院江苏南京210097 南京农业大学动物医学院江苏南京210095 西班牙莱昂大学生理学系莱昂24071

目的 :研究化学性肝损伤对机体免疫机能的影响。方法 :选择 30只健康、1月龄、平均体重 (83 2 0± 2 11)g雌雄各半SD大鼠 ,经一段时间适应性饲养后 ,随机分成四氯化碳 (CCl4 )注射组和对照组。CCl4 注射组大鼠按 0 2mL/ 10 0g体重剂... 详细信息

目的 :研究化学性肝损伤对机体免疫机能的影响。方法 :选择 30只健康、1月龄、平均体重 (83 2 0± 2 11)g雌雄各半SD大鼠 ,经一段时间适应性饲养后 ,随机分成四氯化碳 (CCl4 )注射组和对照组。CCl4 注射组大鼠按 0 2mL/ 10 0g体重剂量每周定时注射CCl4 2次 ,连续注射 8周 ;对照组同时注射等量的橄榄油。观察CCl4诱导的肝损伤对机体免疫功能的影响。结果 :注射CCl4 大鼠外周血T淋巴细胞比例和白细胞介素 2水平显著低于对照组 ,与此同时B淋巴细胞比例却显著高于对照组 ;注射CCl4 组大鼠血浆总蛋白含量和白蛋白、α和 β球蛋白比例下降 ,而γ球蛋白上升。结论 :CCl4 诱导的肝损伤能明显影响大鼠的细胞免疫和体液免疫功能。

关键词：四氯化碳肝损伤免疫机能大鼠

Visualization Location in Q235B Steel Structure by Using the Acoustic emission Tomography

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Journal of Mechanics engineering and Automation 2017年第1期7卷 12-16页

作者： Yu Jiang Zhong Yang Feiyun Xu Bingsheng Xu Antolino gallego College of Intelligent Science and control engineering Jinling Institutes of Technology Nanjing 211169 China School of Mechanical engineering Southeast University Nanjing 211189 China School of Science Nanjing Tech University Nanjing 211800 China School of Building engineering Campus Fuentenueva University of Granada Granada 18071 Spain

AeT （acoustic emission tomography） is a new visualization location method for inspecting and locating the intemal damages in the structures. In this paper, the AeT is applied to detect and visualize damage source locations in the Q235B steel structure to validate its effectiveness. Firstly, the ABAQUS/explicit simulation *** the steel structure with one damaged circle in its center is built. And then, the simulated Ae signals are obtained to establish the Ae tomography. The results show that the damaged circle in the created model can be visualized clearly with the AeT in its original location. Finally, the damage source location based on AeT is compared with the traditional TOA （time of arrival） location method, and the better location accuracy is obtained. And this fact that further illustrates the AeT has a great potential in the application of structure damage detection.

关键词： AeT damage location visualization.

INVeRSe PROBLeMS FOR A GeNeRAL MULTI-CONNeCTeD BOUNDeD DRUM WITH APPLICATIONS IN PHYSICS

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Acta Mathematica Scientia 2003年第1期23卷 104-116页

作者： e.M.e.Zayed Mathematics Department Faculty of Science Zagazig University Zagazig Egypt

This paper studies the influence of a finite container on an ideal *** trace of the heat kernel (t) =exp, where are the eigenvalues of the negative Laplacian -in Rn(n = 2 or 3), is studied for a general multi-connected bounded drum ft which is surrounded by simply connected bounded domains Ωi with smooth boundaries Ωi(i = 1,… ,m) where the Dirichlet, Neumann and Robin boundary conditions on Ωi(i = 1,…,m) are considered. Some geometrical properties of Ω are determined. The thermodynamic quantities for an ideal gas enclosed in Ω are examined by using the asymptotic expansions of (t) for short-time t. It is shown that the ideal gas can not feel the shape of its container Ω, although it can feel some geometrical properties of it.

关键词： Inverse problem heat kernel eigenvalues an ideal gas multi-connected bounded domain

The Asymptotics of the Two-Dimensional Wave equation for a General Multi-Connected Vibrating Membrane with Piecewise Smooth Robin Boundary Conditions

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Acta Mathematica Sinica,english Series 2004年第2期20卷 209-222页

作者： e.M.e.ZAYeD Department of Mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

The asymptotic expansion for small |t| of the trace of the wave kernel , where and are the eigenvalues of the negative Laplacian in the (x 2,x 2)-plane, is studied for a multi-connected vibrating membrane ? in R 2 surrounded by simply connected bounded domains ? j with smooth boundaries ?? j (j = 1, ..., n), where a finite number of piecewise smooth Robin boundary conditions on the piecewise smooth components Γ i (i = 1+k j?1, ..., k j ) of the boundaries ?? j are considered, such that and k 0 = 0. The basic problem is to extract information on the geometry of ? using the wave equation approach. Some geometric quantities of ? (e. g. the area of ?, the total lengths of its boundary, the curvature of its boundary, the number of the holes of ?, etc.) are determined from the asymptotic expansion of the trace of the wave kernel for small |t|.

关键词： Inverse problem Wave kernel eigenvalues Robin boundary conditions Vibrating membrane Hearing the shape of a drum

The 3D Inverse Problem of the Wave equation for a General Multi-connected Vibrating Membrane with a Finite Number of Piecewise Smooth Boundary Conditions

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Acta Mathematica Sinica,english Series 2005年第4期21卷 733-752页

作者： e.M.e.ZAYeD Mathematics Department Faculty of ScienceZagazig UniversityZagazig.Egypt

The trace of the wave kernel μ（t） =∑ω=1^∞ exp（-iteω^1/2）, where {eω}ω^∞=1 are the eigenvalues of the negative Laplacian -△↓2 = -∑k^3=1 （δ/δxk）^2 in the （x^1, x^2, x^3）-space, is studied for a variety of bounded domains, where -∞ 〈 t 〈 ∞ and i= √-1. The dependence of μ （t） on the connectivity of bounded domains and the Dirichlet, Neumann and Robin boundary conditions are analyzed. Particular attention is given for a multi-connected vibrating membrane Ω in Ra surrounded by simply connected bounded domains Ω j with smooth bounding surfaces S j （j = 1,……, n）, where a finite number of piecewise smooth Dirichlet, Neumann and Robin boundary conditions on the piecewise smooth components Si^＊（i = 1 ＋ kj-1,……, kj） of the bounding surfaces S j are considered, such that S j = Ui-1＋kj-1^kj Si^＊, where k0=0. The basic problem is to extract information on the geometry Ω by using the wave equation approach from a complete knowledge of its eigenvalues. Some geometrical quantities of Ω （e.g. the volume, the surface area, the mean curvuture and the Gaussian curvature） are determined from the asymptotic expansion ofexpansion of μ（t） for small │t│.

关键词： Inverse problem Wave kernal eigenvalues Greens function Multi-connected vibrating membrane Negative Laplacian Heat kernel