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Whole-mine subsidence over tabular deposits and related seismicity

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International Journal of mining Science and Technology 2017年第1期27卷 171-177页

作者： Pariseau William g. mcCarterr michael k. Department of mining Engineering University of UtahSalt Lake CityUTUSA

The challenge of estimating mine-wide subsidence and link.ges to seismicity over tabular deposits is addressed by a special finite element technique(dual node–dual mesh). Subsidence and mine-induced seismicity begins near the face when caving occurs and propagates to the surface as extraction reaches a critical extent. Thus, the challenge is to obtain details at the face at the meter scale and also at the surface over the whole mine at the k.lometer scale. Interactions between old and new sections of a mine are automatically tak.n into account with this technique. The finite element method is well established technology based on fundamentals of physical laws, k.nematics and material laws. With this technique, no empirical ‘‘scaling" or fitting computer output by input data ‘‘adjustment" to mine measurements is necessary. Capability is demonstrated for doing practical whole-mine subsidence analysis from first principles. mine-induced seismicity is shown to correlate well with face advance and element failure.

关键词： Whole mine subsidence multi-scale Finite element analysis mine induced seismicity

Nonlinear convection in a non-Darcy porous medium

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Applied mathematics and mechanics(English Edition) 2010年第5期31卷 565-574页

作者： m. k. PARTHA Department of mathematics Malnad College of Engineering

In this paper, the natural convection in a non-Darcy porous medium is studied using a temperature-concentration-dependent density relation. The effect of the two parameters responsible for the nonlinear convection is analyzed for different values of the inertial parameter, dispersion parameters, Rayleigh number, Lewis number, Soret number, and Dufour number. In the aiding buoyancy, the tangential velocity increases steeply with an increase in the nonlinear temperature parameter and the nonlinear concentration parameter when the inertial effect is zero. However, when the inertial effect is non-zero, the effect of the nonlinear temperature parameter and the nonlinear concentration parameter on the tangential velocity is marginal. The concentration distribution varies appreciably and spreads in different ranges for different values of the double dispersion parameters, the inertial effect parameter, and also for the parameters which control the nonlinear temperature and the nonlinear concentration. Heat and mass transfer varies extensively with an increase in the nonlinear temperature parameter and the nonlinear concentration parameter depending on Dacry and non-Darcy porous media. The variation in heat and mass transfer when all the effects, i.e., the inertial effect, double dispersion ef- fects, and Soret and Dufour effects, are simultaneously zero and non-zero. The combined effects of the nonlinear temperature parameter, the nonlinear concentration parameter and buoyancy are analyzed. The effect of the nonlinear temperature parameter and the nonlinear concentration parameter and also the cross diffusion effects on heat and mass transfer are observed to be more in Darcy porous media compared with those in non- Darcy porous media. In the opposing buoyancy, the effect of the temperature parameter is to increase the heat and mass transfer rate, whereas that of the concentration parameter is to decrease.

关键词： non-Darcy porous medium natural convection double dispersion

Cholesterol synthesis inhibition or depletion in axon regeneration

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Neural Regeneration Research 2022年第2期17卷 271-276页

作者： bor Luen tang Department of Biochemistry Yong Loo Lin School of MedicineNational University Health SystemNational University of SingaporeSingapore

Cholesterol is biosynthesized by all animal cells. Beyond its metabolic role in steroidogenesis, it is enriched in the plasma membrane where it has k.y structural and regulatory functions. Cholesterol is thus presumably important for post-injury axon regrowth, and this notion is supported by studies showing that impairment of local cholesterol reutilization impeded regeneration. However, several studies have also shown that statins, inhibitors of 3-hydroxy-3-methylglutaryl-Co A reductase, are enhancers of axon regeneration, presumably acting through an attenuation of the mevalonate isoprenoid pathway and consequent reduction in protein prenylation. Several recent reports have now shown that cholesterol depletion, as well as inhibition of cholesterol synthesis per se, enhances axon regeneration. Here, I discussed these findings and propose some possible underlying mechanisms. The latter would include possible disruptions to axon growth inhibitor signaling by lipid raft-localized receptors, as well as other yet unclear neuronal survival signaling process enhanced by cholesterol lowering or depletion.

关键词： axon regeneration cholesterol 3-hydroxy-3-methylglutaryl-CoA reductase(Hmg-CoA reductase) lipid raft methyl-β-cyclodextrin Nogo receptor prominin-1 RhoA statins

LR-normal orthogroups

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Science China mathematics 2006年第3期49卷 330-341页

作者： SHUm k. P. SEN m. k. Faculty of Science Department of Pure mathematics

A new k.nd of regular orthogroups, namely, the LR-normal orthogroups is introduced and investigated. In particular, we will introduce the gearing techniques for fitting semigroup components on a semilattice in the con... 详细信息

关键词： LR-regular orthogroups, LR-normal orthogroups, gearing of semigroups.

Distribution of Pill millipedes (Arthrosphaera) and Associated Soil Fauna in the Western ghats and West Coast of India

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Pedosphere 2008年第6期18卷 749-757页

作者： k. m. ASHWINI k. R. SRIDHAR microbiology and Biotechnology Department of Biosciences Mangalore University Mangalagangotri

Seven sampling sites in each of three biomes (Western ghats, foothills of Western ghats and west coast) of south- western India were investigated to study the distribution, abundance and ecology of pill millipedes (Arthrosphaera) and associated fauna in relation to edaphic features. Abundance and biomass of Arthrosphaera and other millipedes were the highest in Western ghats, while earthworms were in foothills. Arthrosphaera magna and Arthrosphaera spp. were common in Western ghats and foothills respectively, while no Arthrosphaera were found in the west coast. None of the sampling sites consisted of more than one species of Arthrosphaera. Biomass of Arthrosphaera, other millipedes and earthworms significantly differed in Western ghats (P = 9.48 × 10-7) and foothills (P = 1.35 × 10-8), as did the biomass of species of Arthrosphaera (P = 2.76 × 10-7) between Western ghats and foothills. Correlation analysis revealed that biomass of Arthrosphaera was significantly (P = 0.01, r = 0.45) correlated with soil organic carbon rather than other edaphic fea- tures (pH, phosphate, calcium and magnesium). Distribution pattern, abundance, biomass and ecology of Arthrosphaera of Western ghats in relation to soil qualities were compared with millipedes of other regions of the world.

关键词： Arthrosphaera distribution edaphic features pill millipedes Western ghats

A 4-quadrant Curvelet Transform for Denoising Digital Images

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International Journal of Automation and computing 2013年第3期10卷 217-226页

作者： P. k. Parlewar k. m. Bhurchandi Department of Electronic and Communication Engineering Ramdeobaba College of Engineering and Management Department of Electronic Engineering Visvesvaraya National Institute of Technology

The conventional discrete wavelet transform （DWT） introduces artifacts during denoising of images containing smooth curves. Finite ridgelet transform （FRIT） solved this problem by mapping the curves in terms of small curved ridges. However, blind application of FRIT all over an image is computationally heavy. Finite curvelet transform （FCT） selectively applies FRIT only to the tiles containing small portions of a curve. In this work. a novel curvelet transform named as 4-quadrant finite curvelet transform （4QFCT） based on a new concept of 4-quadrant finite ridgelet transform （4QFRIT） has been proposed. An image is band pass filtered and the high frequency bands are divided into small non-overlapping square tiles. The 4QFRIT is applied to the tiles containing at least one curve element. Unlik. FRIT, the 4QFRIT tak.s 4 sets of radon projections in all the 4 quadrants and then averages them in time and frequency domains after denoising. The proposed algorithm is extensively tested and benchmark.d for denoising of images with gaussian noise using mean squared error （mSE） and peak.signal to noise ratio （PSNR）. The results confirm that 4QFCT yields consistently better denoising performance quantitatively and visually.

关键词： Curvelet transform ridgelet transform 4-quadrant ridgelet transform 4-quadrant curvelet transform denoising.

A Systems Biological Perspective of Cellular Stress-Directed Programmed Cell Death

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Computational molecular Bioscience 2014年第1期4卷 28-34页

作者： Orsolya k.puy Beáta Lizák.Ibolya Stiller gábor Bánhegyi Department of medical Chemistry Molecular Biology and Pathobiochemistry Semmelweis UniversityBudapest Hungary

Each euk.ryotic cell of multicellular organisms must be able to maintain its integrity by sensing both external and internal stimuli. The primary goal of the generated response mechanism is to drive back.the system to the former or to a new homeostatic state. moreover, the response has to provide an accurate survival-or-death decision to avoid any “misunderstanding” and its unwanted consequences. New data revealed that a systems-level crosstalk.of molecular network. has an essential role in achieving the correct characteristic of the response. Although many molecular components of these processes already have been revealed, several elements and regulatory connections of crosstalk.are still missing. These “gaps” of the complex control network. mak. hardly impossible to present comprehensive models. Therefore we approach the questions from a systems biology aspect by combining the experimental results with the special technique of mathematical modelling. In this short report we discuss some novel and preliminary data gained by this approach on the crosstalk.between life and death decisions under cellular stress, to get a systems biological view of these network..

关键词： Systems Biology Cellular Stress Autophagy Apoptosis Crosstalk mathematical modelling

Electroconvulsive therapy:80 years old and still going strong

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World Journal of Psychiatry 2019年第1期9卷 1-6页

作者： gábor gazdag gabor S Ungvari First Department of Psychiatry and Psychiatric Rehabilitation Jahn Ferenc South Pest HospitalBudapest 1204Hungary Department of Psychiatry and Psychotherapy Semmelweis University Medical School1083 BudapestHungary University of Notre Dame FremantleWA 6009Australia Division of Psychiatry School of MedicineUniversity of Western AustraliaCrawleyWA 6009Australia

Electroconvulsive therapy(ECT),which is among the oldest and most controversial treatments in the field of psychiatry,has its 80th birthday this *** this brief historical overview,the discovery of the therapeutic effects of convulsive therapy by Laszlómeduna,and the circumstances that motivated Ugo Cerletti and Lucio Bini to use electricity as a means of seizure induction are ***’s original theory about the antagonism between epilepsy and schizophrenia has been replaced by hypotheses on the mechanism of action of *** position of ECT in modern psychiatry is also discussed with special attention to its most important clinical indications,including catatonia,and preand postpartum affective and psychotic states that are responsive to ECT and in which ECT may even be *** effects and comparison of ECT with recently developed brain stimulation methods are also *** negative media portrayal of ECT and its earlier misuse may have contributed to its negative professional and public perceptions indicated repeatedly in attitude *** negative attitude has played an important role in the decreasing use of ECT in the developed world and a reduction in access to ECT,which constitutes a violation of psychiatric patients’right to an effective treatment.

关键词： Electroconvulsive therapy History Indications Utilization Attitudes

On the Non-Commutative Neutrix Product of the Distributions x＋^λ and x^＋μ

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Acta mathematica Sinica,English Series 2006年第6期22卷 1639-1644页

作者： B.FISHER k.ta■ Department of mathematics University of Leicester Department of mathematics Cankaya University

Let f and g be distributions and let gn = （g ＊ δn）（x）, where δn （x） is a certain converging to the Dirac delta function. The non-commutative neutrix product fog of f and g to be the limit of the sequence {fgn }, provided its limit h exists in the sense that sequence is defined N-lim n-∞（f（x）g,, （x）, φ（x）〉 = （h（x）, φ（x）},for all functions p in 2. It is proved that （x^λ＋1n^px＋）0（x^μ＋1n^qx＋）=x＋^λμ1n^p＋qx＋,（x^λ-1n^qx-）=x-^λ＋μ1n^p＋qx-,for λ＋μ〈-1; λ,μ, λ＋μ≠-1,-2…and p,q=0,1,2……

关键词： distribution delta function product of distributions