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Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano sergei A.Kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRyCIs) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

separation of closely spaced modes by combining complex envelope displacement analysis with method of generating intrinsic mode functions through filtering algorithm based on wavelet packet decomposition

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Applied Mathematics and Mechanics(English Edition) 2013年第7期34卷 801-810页

作者： y.s.KIM 陈立群 shanghai Institute of Applied Mathematics and Mechanics Department of Mechanics Kim Ⅱ Sung University Department of Mechanics College of Sciences Shanghai University shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai University

One of the important issues in the system identification and the spectrum analysis is the frequency resolution, i.e., the capability of distinguishing between two or more closely spaced frequency components. In the modal identification by the empirical mode decomposition （EMD） method, because of the separating capability of the method, it is still a challenge to consistently and reliably identify the parameters of structures of which modes are not well separated. A new method is introduced to generate the intrin- sic mode functions （IMFs） through the filtering algorithm based on the wavelet packet decomposition （GIFWPD）. In this paper, it is demonstrated that the CIFWPD method alone has a good capability of separating close modes, even under the severe condition beyond the critical frequency ratio limit which makes it impossible to separate two closely spaced harmonics by the EMD method. However, the GIFWPD-only based method is impelled to use a very fine sampling frequency with consequent prohibitive computational costs. Therefore, in order to decrease the computational load by reducing the amount of samples and improve the effectiveness of separation by increasing the frequency ratio, the present paper uses a combination of the complex envelope displacement analysis （CEDA） and the GIFWPD method. For the validation, two examples from the previous works are taken to show the results obtained by the GIFWPD-only based method and by combining the CEDA with the GIFWPD method.

关键词： empirical mode decomposition (EMD) wavelet packet decomposition com- plex envelope displacement analysis (CEDA) closely spaced modes modal identification

Near-surface Correction on seismic and Gravity Data

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Journal of Earth science 2015年第6期26卷 851-857页

作者： s.Bychkov I.y.Mityunina Perm state University Mining Institute of Ural Branch of Russian Academy of Sciences

It is important and urgent to work out better statics correction methods to facilitate seismic prospecting. This paper presents a new method of statics correction calculation based on development of a seismic-gravity model of the near surface. Gravity interpretation includes determination of the local component caused by the near surface effects and calculation of the near-surface rock density by solving the linear inverse gravity problem. To obtain the near-surface velocities, priori seismic data such as time fields of the first waves recorded in the initial part of common depth point（CDP） seismograms are used. An optimal near-surface model is retrieved on the basis of the successive solution of the inverse and forward seismic problems, correlating with the observed seismic data. Matching of seismic and gravity model of the near surface yields the maximum coefficient of correlation between the values of velocities and densities. At the end of the interactive iterative process we get values of the near-surface seismic wave velocities, used for statics evaluation, and values of gravity anomalies, calculated with a variable density of the interbedded layer. The applications of the proposed method at geophysical exploration of oil and gas confirm the possibility of calculation of statics correction using the gravimetric data by constructing a coherent seismic-gravity model of the near surface.

关键词： gravity near-surface velocity seismic-gravity model statics correction.

Validation of critical strain technique for assessing stability of coal mine intersections and its potential for development of roof control plans

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第2期10卷 380-389页

作者： s.sinha y.P.Chugh Colorado school of Mines GoldenCOUSA southern Illinois University CarbondaleIL 62901USA

Both room-and-pillar and longwall mining systems develop underground excavations whose stability must be ensured over their entire service life. Even though rock bolts have been extensively used as a support element in Us coal mines for about 40 years, limited research has been conducted in quantifying its composite reinforcement effects. Recently, the authors suggested an approach to quantify the reinforcement effect of roof supports over a designated area based on critical failure strains in tension, compression and shear. This paper validates the critical strain technique(CsT) using a case study and justifies the magnitude of selected critical strain by corroborating with the Us roof fall statistics. Intersections are vulnerable to failure due to the larger exposed roof span and associated stress concentrations. Through numerical application of the CsT to a case study, it was demonstrated that modifying the opening orientation and installing reinforcement at critical locations can help to improve the overall stability of intersections.

关键词： Roof support Critical strain approach Numerical modeling

Deflecting Easy-axis of Fe_3O_4 single Crystal Nanowires by Magnetic-field-induced Method

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Journal of Materials science & Technology 2012年第11期28卷 976-980页

作者： W. Wang s. y. Wang College of Physics and Technology Nanjing Normal University Nanjing 210046 China school of Transportation Southeast University Nanjing 210096 China

In order to control the orientation of easy-axis of magnetic nanowires, FesO4 single crystal nanowires with easy-axis perpendicular to wire-axis were prepared successfully by means of a magnetic-field-induced method. Analysis of X-ray diffraction and electron diffraction pattern showed that there was a wide-angle deflection of easy-axis in the prepared Fe304 nanowires. A high saturation magnetization （82 emu/g） of the FesO4 nanowires was achieved at room temperature. The benefits and mechanism of the deflection of easy-axis from its wire-axis in FesO4 single crystal nanowires were discussed. The results are expected to broaden the magnetic properties of traditional ferrite nanowires.

关键词： Magnetic-field-induced Fea04 nanowire Easy-axis

Positron-Lithium Atom and Electron-Lithium Atom scattering systems at Intermediate and High Energies

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Chinese Physics Letters 2006年第7期23卷 1753-1756页

作者： K. Ratnavelu s. y. Ng Institute of Mathematical sciences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia Department of Physics Faculty of Science National University of Singapore Singapore

The coupled-channel optical method is used to study positron scattering by atomic lithium at energies ranging from the ionization threshold to 60eV, The present method simultaneously treats the target channels and the positronium （Ps） channels in the coupled-channel method together with the continuum effects via an ab-initio optical potential. Ionization, elastic and inelastic cross sections in target channels, and the total cross section are also reported and compared with other theoretical and experimental data. A comparative study with the corresponding electron-lithium data is also reported.

关键词： CLOsE-COUPLING THEORy HyDROGEN sCATTERING CROss-sECTIONs COLLIsIONs

New approaches to cognitive work analysis through latent variable modeling in mining operations

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International Journal of Mining science and Technology 2019年第4期29卷 549-556页

作者： s.Li y.A.sari M.Kumral Department of Mining and Materials Engineering McGill University

This paper discusses the utilization of latent variable modeling related to occupational health and safety in the mining *** variable modeling,which is a statistical model that relates observable and latent variables,could be used to facilitate researchers’understandings of the underlying constructs or hypothetical factors and their magnitude of effect that constitute a complex *** enhanced understanding,in turn,can help emphasize the important factors to improve mine *** most commonly used techniques include the exploratory factor analysis(EFA),the confirmatory factor analysis(CFA)and the structural equation model with latent variables(sEM).A critical comparison of the three techniques regarding mine safety is *** applications of latent variable modeling in mining engineering are *** this scope,relevant research papers were *** suggest that the application of such methods could prove useful in mine accident and safety *** of latent variables analysis in cognitive work analysis was proposed to improve the understanding of human-work relationships in mining operations.

关键词： Latent variables Exploratory factor analysis Confirmatory factor analysis structural equation modeling Occupational health and safety Mine safety

Decomposition of trifluoromethane in a dielectric barrier discharge non-thermal plasma reactor

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Journal of Environmental sciences 2012年第7期24卷 1234-1239页

作者： M. sanjeeva Gandhi y. s. Mok Department of Chemical and Biological Engineering Jeju National University

The decomposition of trifluoromethane （CHF3） was carried out using non-thermal plasma generated in a dielectric barrier discharge （DBD） reactor. The effects of reactor temperature, electric power, initial concentration and oxygen content were examined. The DBD reactor was able to completely destroy CHF3 with alumina beads as a packing material. The decomposition efficiency increased with increasing electric power and reactor temperature. The destruction of CHF3 gradually increased with the addition of O2 up to 2%, but further increase in the oxygen content led to a decrease in the decomposition efficiency. The degradation pathways were explained with the identified by-products. The main by-products from CHF3 were found to be COF2, CF4, CO2 and CO although the COF2 and CF4 disappeared when the plasma were combined with alumina catalyst.

关键词： trifluoromethane plasma alumina dielectric barrier discharge decomposition

Exponential Compact Higher Order scheme for Nonlinear steady Convection-Diffusion Equations

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Communications in Computational Physics 2011年第4期9卷 897-916页

作者： y.V.s.s.sanyasiraju Nachiketa Mishra Department of Mathematics Indian Institute of Technology MadrasChennai 600036India

This paper presents an exponential compact higher order scheme for Convection-Diffusion Equations(CDE)with variable and nonlinear convection *** scheme is O(h4)for one-dimensional problems and produces a tri-diagonal system of equations which can be solved efficiently using Thomas *** twodimensional problems,the scheme produces an O(h4+k4)accuracy over a compact nine point stencil which can be solved using any line iterative approach with alternate direction implicit *** convergence of the iterative procedure is guaranteed as the coefficient matrix of the developed scheme satisfies the conditions required to be *** number analysis has been carried out to establish that the scheme is comparable in accuracy with spectral *** higher order accuracy and better rate of convergence of the developed scheme have been demonstrated by solving numerous model problems for one and two-dimensional CDE,where the solutions have the sharp gradient at the solution boundary.

关键词： Finite difference higher order exponential compact convection-diffusion