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electrical Relaxation in Mixed Alkali Bi_2O_3-K_2O-Li_2O-fe_2O_3 Glasses

Journal of Materials Science & Technology 2006年第5期22卷 701-707页

作者： e.e.Shaisha Sh.f.el-Desouki I.Shaltout A.A.Bahgat Department of physics faculty of science Al-Azhar UniversityNasr CityCairo 11884Egypt

A new glass system （Bi2O3）50（fe2O3）10（Li2O）x（K2O）40-x, where x changes in steps of 5 mole.f.action between 0 and 40, was selected to study the electrical relaxation and the mixed alkali e.f.ct （MAe） phenomena. Measurements of ac conductivity σac, dielectric permittivity ε′ and loss factor tanδ in the.f.equency range of 0.12～10^2 kHz and in the temperature range of 300～650 K were carried out. The temperature dependence of the ac conductivity shows a slow increasing rate at low temperature and high frequency and a rapid increase at high temperature and low frequency. At constant temperature, the ac conductivity is found to be proportional to ω^8, where s is the.f.equency exponent, which is less than 1. Analysis of the conductivity data and the.f.equency exponent shows that the overlapping large polaron tunnelling （OLPT） model of ions is the most favorable mechanism for the ac conduction in the present glass system. The ac response, the dc conductivity and dielectric relaxation have the same activation energy and they originate.f.om the same basic transport mechanism. The results of the dielectric permittivity show no maximum peak in the temperature and frequency range studied. This absence of maximum peak is an indication of non-ferroelectric behavior of all the studied samples. The MAe has been detected in the ac conductivity, which is the same as the classical MAe in the dc conductivity. The electrical parameters such as dielectric permittivity ε′ and real dielectric modulus M′ show a typical minimum deviation from linearity by about two orders of magnitude. The loss factor tanδ and the imaginary dielectric modulus M″ are insignificantly dependent on composition even at the same transition temperature Tg.

关键词： Dielectric permittivity Dielectric modulus Loss factor Conduction mechanism MAe (mixed alkali e.f.ct)

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Olfactory Dysfunction as an early Biomarker in Parkinson's Disease

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Neuroscience Bulletin 2017年第5期33卷 515-525页

作者： Michelle e.f.llard James f.Morley John e.Duda Parkinson's Disease Research Education and Clinical Center Corporal Michael J. Crescenz VA Medical CenterPhiladelphia PA 19104 USA Department of Neurology University of Pennsylvania School of Medicine Philadelphia PA 19104 USA

Olfactory dysfunction is common in Parkinson＇s disease （PD） and often predates the diagnosis by years, reflecting early deposition of Lewy pathology, the histo- logic hallmark of PD, in the olfactory bulb. Clinical tests are available that allow for the rapid characterization of olfactory dysfunction, including tests of odor identification, discrimination, detection, and recognition thresholds, memory, and tests assessing the build-up of odor intensity across increasing suprathreshold stimulus concentrations. The high prevalence of olfactory impairment, along with the ease and low cost of assessment, has fostered great interest in olfaction as a potential biomarker for PD. Hyposmia may help differentiate PD from other causes of parkinsonism, and may also aid in the identification of ＂pre-motor＂ PD due to the early pathologic involvement of olfactory pathways. Olfactory function is also correlated with other non-motor features of PD and may serve as a predictor of cognitive decline. In this article, we summarize the existing literature on olfaction in PD, focusing on the potential for olfaction as a biomarker for early or differential diagnosis and prognosis.

关键词： Olfaction · Parkinson's disease · Biomarker ·Parkinsonism · Pathology

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SYNGR4 and PLeKHB1 deregulation in motor neurons of amyotrophic lateral sclerosis models: potential contributions to pathobiology

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Neural Regeneration Research 2022年第2期17卷 266-270页

作者： Rita f.Marques Kent e.Duncan Institute.f.r Biochemistry and Molecular Biology Department of ChemistryUniversity of HamburgHamburgGermany Neuronal Translational Control Research Group Center for Molecular Neurobiology Hamburg(ZMNH)University Medical Center Hamburg-EppendorfHamburgGermany

Amyotrophic lateral sclerosis is the most common adult-onset neurodegenerative disease affecting motor neurons. Its defining feature is progressive loss of motor neuron function in the cortex, brainstem, and spinal cord, leading to paralysis and death. Despite major advances in identifying genes that can cause disease when mutated and model the disease in animals and cellular models, it still remains unclear why motor symptoms suddenly appear after a long pre-symptomatic phase of apparently normal function. One hypothesis is that age-related deregulation of specific proteins within key cell types, especially motor neurons themselves, initiates disease symptom appearance and may also drive progressive degeneration. Genome-wide in vivo cell-type-specific screening tools are enabling identification of candidates for such proteins. In this minireview, we.f.rst briefly discuss the methodology used in a recent study that applied a motor neuron-specific RNASeq screening approach to a standard model of TAR DNA-binding protein-43(TDP-43)-driven amyotrophic lateral sclerosis. A key finding of this study is that synaptogyrin-4 and pleckstrin homology domain-containing family B member 1 are also deregulated at the protein level within motor neurons of two unrelated mouse models of mutant TDP-43 driven amyotrophic lateral sclerosis. Guided by what is known about molecular and cellular functions of these proteins and their orthologs, we outline here specific hypotheses for how changes in their levels might potentially alter cellular physiology of motor neurons and detrimentally affect motor neuron function. Where possible, we also discuss how this information could potentially be used in a translational context to develop new therapeutic strategies for this currently incurable, devastating disease.

关键词： amyotrophic lateral sclerosis glucagon-like peptide-1 receptor motor neuron disease mouse model neurodegeneration phosphatidylserine pleckstrin homology domain synaptogyrin TAR DNA-binding protein-43 vesicle transport

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Converting TRex-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.M.Gillies e.Spanswick e.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial e.f.rt to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TRex-RGB data *** methodology established in this study will also be applicable to the upcoming SMILe ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TRex RGB green-line aurora auroral transport model

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All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes f.e.Jorge A.Canal Neto Departamento de.f.sica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de.f.sica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse.f.nctions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made.f.r each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

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日本名列第一

日本名列第一

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作者： e.f.·沃格尔(e.f. Vogel)

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桃树小气候及其改善方法

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福建热作科技 1979年第1期 24-46+49页

作者： e.f.萨维奇,马光美国佐治亚农学院园艺系试验站

桃树对气候非常敏感。要了解某些栽培措施的效应,就必须详细了解贴地层的小气候及其对植株的影响。即使我们可以在一定程度上改善这些控制耐寒力和植株周围环境的因子,然而某些气候条件往往超越植株所能恶受的能力。冬期突然大幅度降温... 详细信息

桃树对气候非常敏感。要了解某些栽培措施的效应,就必须详细了解贴地层的小气候及其对植株的影响。即使我们可以在一定程度上改善这些控制耐寒力和植株周围环境的因子,然而某些气候条件往往超越植株所能恶受的能力。冬期突然大幅度降温会引起严重生理反应,导致植株死亡。气象条件和细菌性溃疡及孢子性溃疡等病害之间存在一定关系。小气候的极端最高和最低,是桃树寒害和早期死亡的主要因子。如果要避免桃树在某些年份遭受巨大损失。预防这种寒害是很重要的。这个问题基本上要考虑从生理上解决,病理上是次要的。若不发生寒害或其它损害,病原体的浸染是罕见的。本试验目的在于确定寒害可能发生的时间和条件,并提出适当的防寒措施。

关键词：形成层隔热材料最高温度分叉分生组织保温材料绝缘材料桃树茎干寒害植株顶部温度测定树皮厚度降温速率

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规模问题

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科学决策 1997年第1期 44-48页

作者： e.f.舒马赫

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On the development of optical peripheral nerve inte.f.ces

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Neural Regeneration Research 2019年第3期14卷 425-436页

作者： Hans e.Anderson Richard f.ff.Weir Department of Bioengineering University of Colorado Denver|Anschutz Medical Campus

Limb loss and spinal cord injury are two debilitating conditions that continue to grow in prevalence. Prosthetic limbs and limb reanimation present two ways of providing affected individuals with means to interact in the world. These techniques are both dependent on a robust inte.f.ce with the peripheral nerve. Current methods for inte.f.cing with the peripheral nerve tend to suffer from low specificity, high latency and insufficient robustness for a chronic implant. An optical peripheral nerve inte.f.ce may solve some of these problems by decreasing invasiveness and providing single axon specificity. In order to implement such an inte.f.ce three elements are required:(1) a transducer capable of translating light into a neural stimulus or translating neural activity into changes in fluorescence,(2) a means for delivering said transducer and(3) a microscope.f.r providing the stimulus light and detecting the.f.uorescence change. There are continued improvements in both genetically encoded calcium and voltage indicators as well as new optogenetic actuators for stimulation. Similarly, improvements in specificity of viral vectors continue to improve expression in the axons of the peripheral nerve. Our work has recently shown that it is possible to virally transduce axons of the peripheral nerve.f.r recording from small fibers. The improvements of these components make an optical peripheral nerve inte.f.ce a rapidly approaching alternative to current methods.

关键词： peripheral nerve inte.f.ces optogenetics optical neural inte.f.ce optical peripheral nerve inte.f.ce GCaMP ArcLight adenoassociated viral vector lentiviral vectors viral vectors implantable microscopy

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elastodynamic solution for plane-strain response of functionally graded thick hollow cylinders by analytical method

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Applied Mathematics and Mechanics(english edition) 2011年第2期32卷 189-202页

作者： M.NIKKHAH f.HONARVAR e.DeHGHAN faculty of Mechanical engineering K.N.Toosi University of Technology

An elastodynamic solution for plane-strain response of functionally graded thick hollow cylinders subjected to uniformly-distributed dynamic pressures at boundary surfaces is presented. The material properties, except Poisson＇s ratio, are assumed to vary through the thickness according to a power law function. To achieve an exact solution, the dynamic radial displacement is divided into two quasi-static and dynamic parts, and for each part, an analytical solution is derived. The quasi-static solution is obtained by means of euler＇s equation, and the dynamic solution is derived using the method of the separation of variables and the orthogonal expansion technique. The radial displacement and stress distributions are plotted for various functionally graded material （fGM） hollow cylinders under different dynamic loads, and the advantages of the presented method are discussed. The proposed analytical solution is suitable.f.r analyzing various arrangements of hollow fGM cylinders with arbitrary thickness and arbitrary initial conditions, which are subjected to arbitrary forms of dynamic pressures distributed uniformly on their boundary surfaces.

关键词： functionally graded material elastodynamic solution hollow cylinder,power law function

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