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Communications on Applied Mathematics and Computation 2022年第3期4卷 1057-1104页

作者： Mohammed Homod Hashim Akil j.Harfash Department of Mathematics College of SciencesUniversity of BasrahBasrahIraq

In Hashim and Harfash(***.2021),using a finite element method,the attraction-repulsion chemotaxis model(P)in space is discretised;finite differences were used to do the same in ***,the existence of a global weak solution to the system(PΔt M)was demonstrated by means of analysis of the convergence of the fully discrete approximate problem(P h,Δt M,).Moreover,the functions{U,Z,V}were proved to represent a global weak solution to the system(PΔt M)by means of a passage to the limit,h→0 of the approximate *** paper’s purpose is to demonstrate that the solutions can be bounded,independent of *** analysis contained in this paper illustrates the idea of the existence of weak solutions to the model(P),that requires passing to the limits,Δt→0+and M→∞.The time stepΔt is subsequently linked to the cutoff parameter M>1 by positing a demand thatΔt=o(M−1),as M→∞,with the result that the cutoff parameter becomes the only parameter in the problem(PΔt M).The solutions can be bounded,independ-ent of M,with the use of special energy estimates,as demonstrated ***,these M-independent bounds on the relative entropy are employed with the purpose of deriving M-independent bounds on the ***,compactness arguments were utilised to explore the convergence of the finite element approximate *** conclu-sion was that a weak solution for(P)***,we introduced the error estimate and the implicit scheme was used to perform simulations in one and two space dimensions.

关键词： finite element Chemotaxis Convergence Weak solution

Cortico-centric effects of general anesthetics on cerebrocortical evoked potentials

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Neuroscience Bulletin 2015年第6期31卷 697-704页

作者： Logan j.Voss james W.Sleigh Anaesthesia Department Waikato District Health Board University of Auckland Waikato Clinical School

Despite their ubiquitous use for rendering patients unconscious for surgery, our understanding of how general anesthetics cause hypnosis remains rudimentary at best. Recent years have seen increased interest in ＂top-down＂ cortico-centric theories of anesthetic action. The aim of this study was to explore this by investigating direct cortical effects of anesthetics on cerebrocortical evoked potentials in isolated mouse brain slices. Evoked potentials were elicited in cortical layer IV by electrical stimulation of the underlying white matter. The effects of three anesthetics （ketamine, etomidate, and isoflurane） on the amplitude, latency, and slope of short-latency evoked potentials were quantified. The N2/P3/N4 potentials - which represent the early cortical response - were enhanced by etomidate （increased P3-N4 slope, P 〈0.01）, maintained by ketamine, and reduced by isoflurane （lower N2/P3 amplitude, P 〈0.01）. These effects closely resemble those seen in vivo for the same drugs and point to a cortical mechanism independent of effects on subcortical structures such as the thalamus.

关键词： anesthesia evoked potentials corticalslice thalamus

Characterization of ASTER GDEM elevation data over vegetated area compared with lidar data

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International journal of Digital Earth 2015年第3期8卷 198-211页

作者： Wenj.an Ni Guoqing Sun Kenneth j.Ranson State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingChina Department of Geographical sciences University of MarylandCollege ParkMDUSA Biospheric Sciences Branch NASA’s Goddard Space Flight CenterGreenbeltMDUSA

Current researches based on areal or spaceborne stereo images with very high resolutions(<1 m)have demonstrated that it is possible to derive vegetation height from stereo *** second version of the Advanced Spaceborne... 详细信息

Current researches based on areal or spaceborne stereo images with very high resolutions(from stereo *** second version of the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM)is the state-of-the-art global elevation data-set developed by stereo ***,the resolution of ASTER stereo images(15 m)is much coarser than areal stereo images,and the ASTER GDEM is compiled products from stereo images acquired over 10 *** forest disturbances as well as forest growth are inevitable in 10 years time *** this study,the features of ASTER GDEM over vegetated areas under both flat and mountainous conditions were investigated by comparisons with lidar *** factors possibly affecting the extraction of vegetation canopy height considered include(1)co-registration of DEMs;(2)spatial resolution of digital elevation models(DEMs);(3)spatial vegetation structure;and(4)terrain *** results show that the accurate coregistration between ASTER GDEM and national elevation dataset(NED)is necessary over mountainous *** correlation between ASTER GDEM minus NED and vegetation canopy height is improved from 0.328 to 0.43 by degrading resolutions from 1 arc-second to 5 arc-second and further improved to 0.6 if only homogenous vegetated areas were considered.

关键词： vegetation canopy height ASTER GDEM NED photogrammetry stereo-mapping

Effects of winter weather on traffic operations and optimization of signalized intersections

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journal of Traffic and Transportation Engineering(English Edition) 2019年第2期6卷 196-208页

作者： Zhengyang Lu Tae j.Kwon Liping fu Big Data Research Center Jianghan University Department of Civil and Environmental Engineering University of Alberta Department of Civil and Environmental Engineering University of Waterloo Intelligent Transportation Systems Research Center Wuhan University of Technology

Adverse winter weather has always been a cause of traffic congestion and road *** mitigate the negative impacts of winter weather, transportation agencies are under increasing pressure to introduce weather responsive traffic management ***, most traffic signal control systems are designed for normal weather conditions and are therefore suboptimal regarding efficiency and safety for controlling traffic during winter snow events due to changes in traffic patterns and driver behaviors. The main objective of this research is to explore how to modify pre-timed traffic signal control parameters under adverse weather conditions to increase traffic efficiency and road *** research consists of two main components. first, we examine the impacts of winter weather on three key traffic parameters, i.e., saturation flow rate, start-up lost time, and free flow speed. Secondly, we investigate the potential benefits of implementing weatherspecific signal control plans for uncoordinated intersections as well as coordinated corridors. Two case studies are conducted, each with varying levels of traffic demand and winter event severity, to compare the performance of different signal plans. Evaluation results from both Synchro and VISSIM show that implementing such signal plans is most beneficial for intersection with a medium level of traffic demand. It is also found that the benefit of implementing weather-responsive plans was more compelling at a coordinatedcorridor level than at an uncoordinated-intersection level.

关键词： Signal optimization Inclement weather Traffic simulation Signal coordination

1Assessing Soil Available Potassium by Cation Exchange Membrane and Conventional Chemical Extractions

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Pedosphere 1999年第1期9卷 91-96页

作者： LIUZHAOHUI j.SCHOENAU 等 ChinaAgriculturalUniversity Beijing100094China DepartmentofSoilScience UniversityofSaskatchewanSask

four testing methods using canon exchange membrane (CEM), ammonium acetate, ASI (0.25 mol L-1 NaHCO3+0.01 mol L-1 EDTA +0.01 mol L-1 NH4P) and 1.0 mol L-1 boiling nitric acid, respectively, were used to evaluate soil available K. The soil K tested by CEM was significantly correlated with that by the other (conventional) methods (r2=0.43**~0.95***). The soil K tested by CEM saturated with NH4HCO3 (15 min extraction) was most closely correlated with that by the other methods (2 =0. 60***~0.95***). Potassium availability, as predicted by soil test, was comparable to actual K uptake by canola and wheat grown on the soils in growth chamber. Regression analyses showed that plant K uptake was more closely correlated with K extracted by CEM (r2=0.56***~0.81***) than that by the conventional methods (r2=0.46***~;0.81***), most closely correlsted with that by NH4HCO3-saturated CEM for 15 min (r2=0.81***), and worst correlated with that by HNO3 (r2=0.45**~0.72***).

关键词： canon exchange resin membrane conventional chemical extractions soil available potassium

Active explosion barrier performance against methane and coal dust explosions

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International journal of Coal Science & Technology 2015年第4期2卷 261-268页

作者： j. j. L. du Plessis Department of Mining Engineering University of PretoriaPretoria 0028 South Africa

Preventing the propagation of methane or coal dust explosions through the use of active explosion-suppression systems remains one of the most underutilised explosion controls in underground coal mines. As part of the effort to develop better technologies to safeguard mines, the use of active barrier systems was investigated at Kloppersbos in South Africa. The system is designed to meet the requirements of the European Standard （EN 14591-4 2007） as well as the Mine Safety Standardisation in the Ministry of Coal Industry, Coal Industrial 1 Standard of the Peoples Republic of China （MT 694-1997）. from the tests conducted, it can be concluded that the ExploSpot System was successful in stopping flame propagation for both methane and methane and coal dust hybrid explosions when ammonium phosphate powder was used as the suppression material. The use of this barrier will provide coal mine management with an additional explosion control close to the point of ignition and may find application within longwall faces further protecting mines against the risk of an explosion propagating throughout a mine.

关键词： Coal Methane Explosions Active barriers

Sam68 is a regulator of Toll-like receptor signaling

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Cellular & Molecular Immunology 2017年第1期14卷 107-117页

作者： jeffrey A Tomalka Tristan j de jesus Parameswaran Ramakrishnan Department of Pathology School of Medicine Case Western Reserve University and University Hospitals Case Medical Center Cleveland OH 44106 USA

Recognition of pathogens by Toll-like receptors （TLR） activate multiple signaling cascades and expression of genes tailored to mount a primary immune response, inflammation, cell survival and apoptosis. Although TLR-induced activation of pathways, such as nuclear factor kappaB （Nf-κB） and mitogen-activated protein kinases （MAPK）, has been well studied, molecular entities controlling quantitative regulation of these pathways during an immune response remain poorly defined. We identified Sam68 as a novel regulator of TLR-induced Nf-κB and MAPK activation. We found that TLR2 and TLR3 are totally dependent, whereas TLR4 is only partially dependent on Sam68 to induce the activation of Nf-KB c-Rel. Absence of Sam68 greatly decreased TLR2- and TLR3-induced Nf-κB p65 activation, whereas TLR4- induced p65 activation in a Sam68-independent manner. In contrast, Sam68 appeared to be a negative regulator of MAPK pathways because absence of Sam68 enhanced TLR2-induced activation of extracellular signal-regulated kinases （ERK） and c-jun N-terminal kinases （jNK）. Interestingly, TLR2- and TLR3-induced gene expression showed a differential requirement of Sam68. Absence of Sam68 impaired TLR2-induced gene expression, suggesting that Sam68 has a critical role in myeloid differentiation primary response gene 88-dependent TLR2 signaling. TLR3-induced gene expression that utilize Toll/Interleukin-1 receptor-domain-containing adapter-inducing beta interferon pathway, depend only partially on Sam68. Our findings suggest that Sam68 may function as an immune rheostat that balances the activation of Nf-κB p65 and c-Rel, as well as MAPK, revealing a potential novel target to manipulate TLR signaling.

关键词： innate immunity MAP kinase Nf-kappaB Sam68 TLR

The Moser-Trudinger-Onofri Inequality

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 777-802页

作者： j.an DOLBEAULT Maria j.ESTEBAN Gaspard jANKOWIAK Ceremade CNRS UMR 7534 and Université Paris-Dauphine Place de Lattre de Tassigny

This paper is devoted to results on the Moser-Trudinger-Onofri inequality, or the Onofri inequality for brevity. In dimension two this inequality plays a role similar to that of the Sobolev inequality in higher dimensions. After justifying this statement by recovering the Onofri inequality through various limiting procedures and after reviewing some known results, the authors state several elementary *** new results are also proved in this paper. A proof of the inequality is given by using mass transportation methods(in the radial case), consistently with similar results for Sobolev inequalities. The authors investigate how duality can be used to improve the Onofri inequality, in connection with the logarithmic Hardy-Littlewood-Sobolev *** the framework of fast diffusion equations, it is established that the inequality is an entropy-entropy production inequality, which provides an integral remainder term. finally,a proof of the inequality based on rigidity methods is given and a related nonlinear flow is introduced.

关键词： Moser-Trudinger-Onofri inequality Duality Mass transportation fast diffusion equation Rigidity

Optic Neuritis in Acute Neuroborreliosis (Lyme Disease) in the U.S.-Mexican Border: Case Report

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World journal of Neuroscience 2016年第2期6卷 126-130页

作者： Ihtesham A. Qureshi Michael f. Maldonado Gustavo j. Rodriguez Salvador Cruz-flores Alberto Maud Neurology Department Texas Tech University Health Sciences Center El Paso USA Ophthalmology Department Texas Tech University Health Sciences Center El Paso USA

Objective: We describe a patient diagnosed with acute neuroborreliosis presenting with anterior optic neuritis (papillitis) in a non-endemic region. Case Presentation: A 43-year-old previously healthy right handed man admitted due to an insidious onset of severe headache and spells of ascending paresthesias from his right foot into his right arm and face followed by speech arrest and clumsiness of his right hand. His neurologic exam was significant for somnolence, nuchal rigidity and Kernig and Brudzinski signs were present. MRI of the brain with gadolinium showed diffuse hyperintense signal involving the supra and infratentorial cortical sulci, with associated faint diffuse leptomeningeal enhancement, consistent most likely with diffuse leptomeningoencephalitis. EEG: normal. CSf VDRL was negative. Dilated fundus exam revealed mild optic nerve edema more significant to the left than to the right eye, confirmed and measured by spectral domain OCT (Optical Coherence Tomography). There was an evidence of posterior uveitis with an early vitreous hemorrhage superficial to the left optic nerve. Lyme disease serum antibody (IgM) Immunoblotting was positive in 2 bands confirming the diagnosis of neuroborreliosis. Conclusion: Optic nerve involvement in Lyme disease is an uncommon complication that should be confirmed by specific diagnostic criteria to establish its causal relation.

关键词： Optic Neuritis Lyme Disease Non-Endemic Papillitis