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Propagation of P-and s-waves in initially stressed gravitating half space

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Applied Mathematics and Mechanics(English Edition) 2013年第7期34卷 847-860页

作者： s. GUPTA s. K. VIsHWAKARMA Department of Applied Mathematics Indian School of Mines

The present paper contributes in studying the phase velocities of P- and s-waves in a half space subjected to a compressive initial stress and gravity field. The density and acceleration due to gravity vary quadratically along the depth. The dispersion equation is derived in a closed form. It is shown that the phase velocities depend not only on the initial stress, gravity, and direction of propagation but also on the inhomogeneity parameter associated with the density and acceleration due to gravity. Various particular cases are obtained, and the results match with the classical results. Numerical investigations on the phase velocities of P- and s-waves against the wave number are made for various sets of values of the material parameters, and the results are illustrated graphically. The graphical user interface model is developed to generalize the effect.

关键词： P-wave s-wave initial stress gravity half space graphical user interface

INEQUALITY OF KORN's TYPE ON COMPACT sURFACEs WITHOUT BOUNDARY

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Chinese Annals of Mathematics,series B 2003年第2期24卷 191-204页

作者： s.MARDARE Laboratoire Jacques-Louis Lions Universite Pierre et Marie Curie4 Place Jussieu75005 ParisFrance.

Inequalities of Korn's type on a surface with boundary have been proved in many papersusing different techniques (see e.g. [4, 5, 11]). The author proves here an inequality of Korn'stype on a compact surface without boundary. The idea is to use a finite number of maps fordefining the surface and the inequality of Korn's type without boundary conditions for everymap and to recast these in a general functional analysis setting about quotient spaces.

关键词： Inequality of Korn's type Compact surface sobolev space

Elevated basal intestinal mucosal cytokine levels in asymptomatic first-degree relatives of patients with Crohn's disease

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World Journal of Gastroenterology 2000年第1期6卷 49-52页

作者： Indaram AVK Nandi s Weissman s Lam s Bailey B Blumstein M Greenberg R Bank s Division of Gastroenterology Long Island Jewish Medical CenterAlbert Einstein College of MedicineNew YorkUSA

AIM To determine levels of cytokines incolonic mucosa of asymptomatic first degreerelatives of Crohn’s disease *** Cytokines(Interleukin(IL)1-Beta,IL-2,IL-5 and IL-8)were measured using ELIsAin biopsy samples of normal looking colonicmucosa of first degree relatives of Crohn’sdisease patients(n = 9)and from normalcontrols(n = 10)with no family history ofCrohn’s *** Asymptomatic first degree relativesof patients with Crohn’s disease had significantlyhigher levels of basal intestinal mucosalcytokines(IL-2,IL-5 and IL-8)than *** these increased cytokinelevels serve as phenotypic markers for a geneticpredisposition to developing Crohns diseaselater on,or whether they indicate early(pre-clinical)damage has yet to be further *** Asymptomatic first degreerelatives of Crohn’s disease patients have higherlevels of cytokines in their normal-lookingintestinal mucosa compared to normal controls,This supports the hypothesis that increasedcytokines may be a cause or an early event inthe inflammatory cascade of Crohns disease andare not merely a result of the inflammatoryprocess.

关键词： subject headings crohns disease cytokine/analysis intestinal mucosa

Detection and clearance in Alzheimer’s disease: leading with illusive chemical, structural and morphological features of the targets

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Neural Regeneration Research 2024年第3期19卷 497-498页

作者： Luís Gales i3s−Instituto de Investigação e Inovação em saúde Rua Alfredo AllenPortoPortugal(Gales L)IBMC−Instituto de Biologia Molecular e CelularUniversidade do PortoRua Alfredo AllenPortoPortugal ICBAs−Instituto de Ciências Biomédicas Abel salazar Rua de Jorge Viterbo FerreiraPortoPortugal

Highly specific interactions between biomolecules,such as antigen-antibody,protein-ligand,or nucleic acid base pair complementary are on the basis of the organization of complex *** same principles may be tentatively used in molecular medicine for diagnosis and therapeutics.A molecule can be designed to selectively bind a protease and thereby inhibit the production of a peptide that forms toxic aggregates in the brain or an antibody may be produced to bind specifically to that peptide for detection or clearance ***,interference in biological systems is not that *** a start there is the inhibition of the physiological role of the protease;moreover,several cleavage fragments may be produced,which may continue to diverge due to putative post-translational modification and self-assembly processes,hiding the toxic target in a“soup”of peptide species varying in size,structure and chemical composition.A perspective of the current status and challenges in targeting peptide species for diagnosis and treatment in the context of Alzheimer’s disease is given.

关键词： Alzheimer diagnosis thereby

starburst amacrine cells,involved in visual motion perception,lose their synaptic input from dopaminergic amacrine cells and degenerate in Parkinson’s disease patients

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Translational Neurodegeneration 2023年第1期12卷 638-653页

作者： Xavier sánchez-sáez Isabel Ortuño-Lizarán Carla sánchez-Castillo Pedro Lax Nicolás Cuenca Department of Physiology Genetics and MicrobiologyUniversity of AlicanteSan Vicente del RaspeigSpain Alicante Institute for Health and Biomedi-cal Research(IsABIAL) AlicanteSpain Ramón Margalef Institute University of AlicanteSan Vicente del RaspeigSpain.

Background The main clinical symptoms characteristic of Parkinson’s disease(PD)are bradykinesia,tremor,and other motor ***,non-motor symptoms,such as visual disturbances,can be identified at early stages of the *** of these symptoms is the impairment of visual motion ***,we sought to determine if the starburst amacrine cells,which are the main cellular type involved in motion direction selectivity,are degenerated in PD and if the dopaminergic system is related to this *** Human eyes from control(n=10)and PD(n=9)donors were available for this *** immunohistochemistry and confocal microscopy,we quantified starburst amacrine cell density(choline acetyltransferase[ChAT]-positive cells)and the relationship between these cells and dopaminergic amacrine cells(tyrosine hydroxylase-positive cells and vesicular monoamine transporter-2-positive presynapses)in cross-sections and wholemount *** First,we found two different ChAT amacrine populations in the human retina that presented different ChAT immunoreactivity intensity and different expression of calcium-binding *** populations are affected in PD and their density is reduced compared to ***,we report,for the first time,synaptic contacts between dopaminergic amacrine cells and ChAT-positive cells in the human *** found that,in PD retinas,there is a reduction of the dopaminergic synaptic contacts into ChAT *** Taken together,this work indicates degeneration of starburst amacrine cells in PD related to dopaminergic degeneration and that dopaminergic amacrine cells could modulate the function of starburst amacrine *** motion perception circuitries are affected in PD,their assessment using visual tests could provide new insights into the diagnosis of PD.

关键词： Parkinson’s disease Retinal neurodegeneration Human retina ChAT amacrine cells Dopaminergic amacrine cells

HF激光脉冲与水柱表面相互作用产生电信号(英文)

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中国光学 2011年第1期4卷 21-25页

作者： ANDREEV s N FIRsOV K N kazantsev s Yu KONONOV I G PAsHININ P P 张来明阮鹏俄罗斯科学院普罗霍罗夫普通物理研究所莫斯科119991 中国科学院长春光学精密机械与物理研究所激光与物质相互作用国家重点实验室吉林长春130033

研究了脉冲HF激光与水柱表面相互作用下电信号的产生过程。电信号显示了与激光能量线性相关的峰值间有时间间隔的两峰结构,且第二个尖峰在水柱底部的蒸汽腔塌缩后出现。实验还显示电信号的幅值和激光脉冲照射过程中是否存在膨胀和挤压... 详细信息

研究了脉冲HF激光与水柱表面相互作用下电信号的产生过程。电信号显示了与激光能量线性相关的峰值间有时间间隔的两峰结构,且第二个尖峰在水柱底部的蒸汽腔塌缩后出现。实验还显示电信号的幅值和激光脉冲照射过程中是否存在膨胀和挤压的薄水层密切相关。如果在电池上边缘和石英平板(石英板紧邻电池,并与水柱上表面相接)之间存在一薄水层,电信号强度会增加10倍。

关键词： HF激光器蒸汽腔薄水层石英平板水柱

sYNTHEsEs AND CHARACTERIZATIONs OF OLIGO(AZOMETHINE ETHER)s DERIVED FROM 2,2'-[1,4-ENYLENEBIs(METHYLENEOXY)]DIBENZALDEHYDE AND 2,2'-[1,2-PHENYLENEBIs(METHYLENEOXY)]DIBENZALDEHYDE

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Chinese Journal of Polymer science 2012年第5期30卷 682-693页

作者： Ismet Kaya süleyman Culhaoglu Canakkale Onsekiz Mart University Faculty of Science and ArtsDepartment of ChemistryCanakkale 17020Turkey

The oligo（azomethine ether）s were synthesized via polycondensation of alkyl diamines with aromatic dialdehydes. Two series of dialdehydes, namely 2,2＇-[1,2-phenylenebis（methyleneoxy）]dibenzaldehyde [2,2＇-1,2-（PBMODB）] and 2,2＇- [1,4-phenylenebis（methyleneoxy）]dibenzaldehyde [2,2＇-I,4-（PBMODB）] were prepared from the condensation reactions of salicylaldehyde with o-xylenedibromide and p-xylenedibromide, respectively. The structures of dialdehydes and oligomers were determined by FT-IR, 1H-NMR and 13C-NMR. The thermal analyses of oligomers were conducted by DsC and TG/DTA techniques, respectively. size exclusion chromatography （sEC） technique was also used to determine molecular weights and molecular weight distributions of oligomers. Electrochemical properties of the synthesized products were investigated.

关键词： Polyazomethine Thermal analysis Dialdehyde Oligoazomethine.

Model dependent analysis of D^(+)_(s)→η^(′)l+v_(l) decays in beyond standard model

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Chinese Physics C 2024年第9期48卷 82-95页

作者： s.Mahata M.Mandal H.Mahapatra s.Biswas s.sahoo Department of Physics National Institute of Technology Durgapur Durgapur 713209West BengalIndia

Motivated by the recent experimental results of branching fractions for D^(+)_(s)→η^(′)l+v_(l) decays,which deviate from their sM predictions,we hve investigated these decays in W' model and scalar leptoquark model to determine potential signatures of new physics(NP) in semileptonic charm decays induced by c→(s,d)l+v_(l) *** recent experimental results of branching fractions for semileptonic D meson decays,new coupling parameters are predicted for the aforementioned NP *** fraction,forward-backward asymmetry,and lepton polarization asymmetry are examined by considering the predicted NP coupling *** results of branching fractions in scalar leptoquark model are found very close to the experimental results and exist around the range of 1σ *** presented a comparative study of the NP models to check their sensitivity on these *** anticipate that further research on these decays will significantly support our findings.

关键词： charm decay new physics W′boson scalar leptoquark flavour changing charged current

Neumann＇s method for boundary problems of thin elastic shells

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Applied Mathematics and Mechanics(English Edition) 2017年第4期38卷 543-556页

作者： Y. s. NEUsTADT Department of Civil Engineering Samara State Architectural and Building University Samara 443001 Russia

The possibility of using Neumann＇s method to solve the boundary problems for thin elastic shells is studied. The variational statement of the static problems for the shells allows for a problem examination within the distribution space. The convergence of Neumann＇s method is proven for the shells with holes when the boundary of the domain is not completely fixed. The numerical implementation of Neumann＇s method normally requires significant time before any reliable results can be achieved. This paper suggests a way to improve the convergence of the process, and allows for parallel computing and evaluation during the calculations.

关键词： boundary problem thin elastic shell theory Neumann's method variational principle Korn's inequality distribution embedding theorem Green tensor