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International Journal of Digital earth 2018年第8期11卷 803-824页

作者： S.R.Phinn e.m.kovacs C.m.Roelfsema R.F.Canto C.J.Collier L.J.mcKenzie Remote Sensing Research Centre School of Earth and Environmental SciencesUniversity of QueenslandSt LuciaAustralia Centre for Tropical Water and TeRRAtic ecosystem Research(TropWATeR) James Cook UniversityCairnsAustralia

Seagrass meadows are at increasing risk of thermal stress and recent work has shown that water temperature around seagrass meadows could be used as an indicator for seagrass *** thermal data have not been linked to the thermal properties of seagrass *** work assessed the covariation between 20 in situ average daily temperature logger measurement sites in tropical seagrass meadows and satellite derived daytime SST(sea surface temperature)from the daytime mODIS and Landsat sensors along the Great Barrier Reef coast in *** significant(R2=0.787–0.939)positive covariations were found between in situ seagrass logger temperatures and mODIS SST temperature and Landsat sensor temperatures at all sites along the *** mODIS SST were consistently higher than in situ temperature at the majority of the sites,possibly due to the sensor’s larger pixel size and location offset from field *** thermal data were lower than field-measured SST,due to differences in measurement scales and *** refined significantly and tested over larger areas,this approach could be used to monitor seagrass health over large(106 km2)areas in a similar manner to using satellite SST for predicting thermal stress for corals.

关键词： Seagrass temperature thermal tolerance satellite sea surface temperature Landsat mODIS Great Barrier Reef

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Samuel e.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain eAAT-1/GLAST eAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Beyond the synucleinopathies:alpha synuclein as a driving force in neurodegenerative comorbidities

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Translational Neurodegeneration 2019年第1期8卷 346-358页

作者： Naomi P.Visanji Anthony e.Lang Gabor G.kovacs edmond J.Safra program in Parkinson’s disease and the morton and Gloria Shulman movement disorders clinic Toronto Western HospitalTorontoOntarioCanada Department of Laboratory medicine and Pathobiology and Tanz Centre for Research in Neurodegenerative Disease University of TorontoTorontoOntarioCanada Laboratory medicine Program&Krembil Brain Institute University Health NetworkTorontoOntarioCanada

The fundamental role that alpha-synuclein(aSyn)plays in the pathogenesis of neurodegenerative synucleinopathies,including Parkinson’s disease,dementia with Lewy bodies,and multiple system atrophy,is a well-accepted fact.A wealth of experimental evidence has linked this relatively small but ubiquitously expressed protein to a plethora of cytopathologic mechanisms and suggests that aSyn may be capable of seeding the progressive spread of synucleinopathy throughout the *** the synucleinopathies,the abnormal deposition of aSyn is frequently seen in a variety of other neurodegenerative proteinopathies including Alzheimer’s *** spite of the fact that the frequency of concomitant aSyn pathology in these disorders is such that it can be considered the rule rather than the exception,the potential role that aSyn may have in these disorders has received relatively little *** this article we postulate that aSyn may in fact be a key protein in driving the pathogenic processes in neurodegenerative *** addition to reviewing the frequency of concomitant deposition of aSyn in the neurodegenerative proteinopathies,we also consider our current understanding of the interaction of aSyn with other neurodegenerative disease-associated proteins,including tau,TDP-43,amyloid-βand prion protein,in the context of neuropathologic studies describing the anatomical sites of potential concomitant *** conclude that a growing body of evidence,encompassing neuropathology studies in human brain,animal models of concomitant proteinopathies and studies employing sophisticated methods of probing protein-protein interaction,cumulatively suggest that aSyn is well positioned to exert a strong influence on the pathogenesis of the neurodegenerative *** hope to stimulate research in this emerging field and consider that future studies exploring the contribution of aSyn to the pathogenic processes in neurodegenerative comorbidities may provide critical

关键词： Amyloid-β Alpha-synuclein Alzheimer’s disease Comorbidity Dementia with Lewy bodies multiple system atrophy Neurodegeneration Parkinson’s disease Prion protein Progressive supranuclear palsy Proteinopathy Tau TDP-43

Germline mLH1 and mSH2 mutational spectrum including frequent large genomic aberrations in Hungarian hereditary non-polyposis colorectal cancer families:Implications for genetic testing

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World Journal of Gastroenterology 2007年第19期13卷 2727-2732页

作者： Janos Papp marietta e kovacs edith Olah Department of molecular Genetics National Institute of Oncology Rath Gy. u. 7-9 H-1122 Budapest Hungary

AIm: To analyze the prevalence of germline mLH1 and mSH2 gene mutations and evaluate the clinical characteristics of Hungarian hereditary non-polyposis colorectal cancer (HNPCC) families. meTHODS: Thirty-six kindreds were tested for mutations using conformation sensitive gel electrophoreses, direct sequencing and also screening for genomic rearrangements applying multiplex ligation-dependent probe amplifi cation (mLPA). ReSULTS: eighteen germline mutations (50%) were identifi ed, 9 in mLH1 and 9 in mSH2. Sixteen of these sequence alterations were considered pathogenic, the remaining two were non-conservative missense alterations occurring at highly conserved functional motifs. The majority of the defi nite pathogenic mutations (81%, 13/16) were found in families fulfilling the stringent Amsterdam Ⅰ/Ⅱ criteria, including three rearrangements revealed by mLPA (two in mSH2 and one in mLH1). However, in three out of sixteen HNPCC-suspected families (19%), a disease-causing alteration could be revealed. Furthermore, nine mutations described here are novel, and none of the sequence changes were found in more than one ***: Our study describes for the f irst time the prevalence and spectrum of germline mismatch repair gene mutations in Hungarian HNPCC and suspected-HNPCC families. The results presented here suggest that clinical selection criteria should be relaxed and detection of genomic rearrangements should be included in genetic screening in this population.

关键词： Germline mutation Hereditary non-polyposis colorectal cancer mLH1 mSH2 Rearrangement

Characterization of novel Brown midrib 6 mutations affecting lignin biosynthesis in sorghum

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Journal of Integrative Plant Biology 2016年第2期58卷 136-149页

作者： erin D. Scully Tammy Gries Deanna L. Funnell-Harris Zhanguo Xin Frank A. kovacs Wilfred Vermerris Scott e. Sattler Grain Forage and Bioenergy Research Unit USDA-ARS Lincoln NE 68583 USA Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE 68583 USA Department of Plant Pathology University of Nebraska-Lincoln Lincoln NE 68583 USA Plant Stress and Germplasm Development Unit USDA-ARS Lubbock TX 79414 USA Department of Chemistry University of Nebraska-Kearney Kearney NE 68849 USA Department of microbiology & Cell Science and UF Genetics Institute University of Florida Gainesville FL 32610 USA

The presence of lignin reduces the quality of lignocellulosic biomass for forage materials and feedstock for biofuels. In C4 grasses, the brown midrib phenotype has been linked to mutations to genes in the monolignol biosynthesis pathway. For example, the Bmr6 gene in sorghum （Sorghum bicolor） has been previously shown to encode cinnamyl alcohol dehydrogenase （CAD）, which catalyzes the final step of the monolignol biosynthesis pathway. mutations in this gene have been shown to reduce the abundance of lignin, enhance digestibility, and improve saccharification efficiencies and ethanol yields. Nine sorghum lines harboring five different bmr6 alleles were identified in an emS-mutagenized TILLING population. DNA sequencing of Bmr6 revealed that the majority of the mutations impacted evolutionarily conserved amino acids while three-dimensional structural modeling predicted that all of these alleles interfered with the enzyme＇s ability to bind with its NAPPH cofactor. All of the new alleles reduced in vitro CAD activity levels and enhanced glucose yields following saccharification. Further, many of these lines were associated with higher reductions in acid detergent lignin compared to lines harboring the previously characterized bmr6-ref allele. These bmr6 lines represent new breeding tools for manipulating biomass composition to enhance forage and feedstock quality.

关键词： Cinnamyl alcohol dehydrogenase (CAD) emS mutagenesis biofuels C4 grass forage

environmental chemical study on the marsh of Fatimid cemetery at Aswan City, egypt

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Journal of environmental Sciences 2002年第4期14卷 464-473页

作者： m.e.Soltan Chemistry Department Faculty of Science

environmental chemical study were carried out on the Fatimid cemetery marsh at Aswan City(24°1'N and 32°9'e), egypt. marsh contents(warter, soil, sediment, metal and nonmetal bearing salts, and emergent weed) were analysed to known the source of marsh water, speciation of the different elements between the marsh contents, and the toleration of emergent weed (Phargmites australies) for different metals and their bioaccumulation coefficients. Thus, metals(Ca, mg, Na, K, Ni, Fe, mn, Cu, Zn, Cd and Pb) and nonmetals(CO 2- 3, HCO - 3, Cl -, SO 2- 4, PO 3- 4, NO - 3, SiO 2, organic matter and pH value) were determined in the samples. According to the chemical analysis, and applying the base exchange equation(water type) and calculate the hydrochemical parameters for marsh water samples, we can indicate that the marsh water is ground water with Na SO 4 type and deep meteoric genesis. Topsoil of marsh dry land characterized by CaCl as dominant salt,while NaCl is a dominant salt in subsoil. The elevated pH values of marsh contents minimized the metal solubilities in different samples. Phragmites australies showed a strong ability to accumulate mn and Fe in the aerial part in opposite to Co, Ni and Cd.

关键词： marsh water soil sediment emergent weed egypt

INVeRSe PROBLemS FOR A GeNeRAL mULTI-CONNeCTeD BOUNDeD DRUm WITH APPLICATIONS IN PHYSICS

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Acta mathematica Scientia 2003年第1期23卷 104-116页

作者： e.m.e.Zayed mathematics Department Faculty of Science Zagazig University Zagazig Egypt

This paper studies the influence of a finite container on an ideal *** trace of the heat kernel (t) =exp, where are the eigenvalues of the negative Laplacian -in Rn(n = 2 or 3), is studied for a general multi-connected bounded drum ft which is surrounded by simply connected bounded domains Ωi with smooth boundaries Ωi(i = 1,… ,m) where the Dirichlet, Neumann and Robin boundary conditions on Ωi(i = 1,…,m) are considered. Some geometrical properties of Ω are determined. The thermodynamic quantities for an ideal gas enclosed in Ω are examined by using the asymptotic expansions of (t) for short-time t. It is shown that the ideal gas can not feel the shape of its container Ω, although it can feel some geometrical properties of it.

关键词： Inverse problem heat kernel eigenvalues an ideal gas multi-connected bounded domain

The 3D Inverse Problem of the Wave equation for a General multi-connected Vibrating membrane with a Finite Number of Piecewise Smooth Boundary Conditions

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Acta mathematica Sinica,english Series 2005年第4期21卷 733-752页

作者： e.m.e.ZAYeD mathematics Department Faculty of ScienceZagazig UniversityZagazig.Egypt

The trace of the wave kernel μ（t） =∑ω=1^∞ exp（-iteω^1/2）, where {eω}ω^∞=1 are the eigenvalues of the negative Laplacian -△↓2 = -∑k^3=1 （δ/δxk）^2 in the （x^1, x^2, x^3）-space, is studied for a variety of bounded domains, where -∞ 〈 t 〈 ∞ and i= √-1. The dependence of μ （t） on the connectivity of bounded domains and the Dirichlet, Neumann and Robin boundary conditions are analyzed. Particular attention is given for a multi-connected vibrating membrane Ω in Ra surrounded by simply connected bounded domains Ω j with smooth bounding surfaces S j （j = 1,……, n）, where a finite number of piecewise smooth Dirichlet, Neumann and Robin boundary conditions on the piecewise smooth components Si^＊（i = 1 ＋ kj-1,……, kj） of the bounding surfaces S j are considered, such that S j = Ui-1＋kj-1^kj Si^＊, where k0=0. The basic problem is to extract information on the geometry Ω by using the wave equation approach from a complete knowledge of its eigenvalues. Some geometrical quantities of Ω （e.g. the volume, the surface area, the mean curvuture and the Gaussian curvature） are determined from the asymptotic expansion ofexpansion of μ（t） for small │t│.

关键词： Inverse problem Wave kernal eigenvalues Greens function multi-connected vibrating membrane Negative Laplacian Heat kernel

The Asymptotics of the Two-Dimensional Wave equation for a General multi-Connected Vibrating membrane with Piecewise Smooth Robin Boundary Conditions

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Acta mathematica Sinica,english Series 2004年第2期20卷 209-222页

作者： e.m.e.ZAYeD Department of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt

The asymptotic expansion for small |t| of the trace of the wave kernel , where and are the eigenvalues of the negative Laplacian in the (x 2,x 2)-plane, is studied for a multi-connected vibrating membrane ? in R 2 surrounded by simply connected bounded domains ? j with smooth boundaries ?? j (j = 1, ..., n), where a finite number of piecewise smooth Robin boundary conditions on the piecewise smooth components Γ i (i = 1+k j?1, ..., k j ) of the boundaries ?? j are considered, such that and k 0 = 0. The basic problem is to extract information on the geometry of ? using the wave equation approach. Some geometric quantities of ? (e. g. the area of ?, the total lengths of its boundary, the curvature of its boundary, the number of the holes of ?, etc.) are determined from the asymptotic expansion of the trace of the wave kernel for small |t|.

关键词： Inverse problem Wave kernel eigenvalues Robin boundary conditions Vibrating membrane Hearing the shape of a drum

Asymptotic expansions of the Heat Kernel of the Laplacian for General Annular Bounded Domains with Robin Boundary Conditions：Further Results

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Acta mathematica Sinica,english Series 2003年第4期19卷 679-694页

作者： e.m.e.ZAYeD Departmentofmathematics FacultyofScienceZagazigUniversityZagazigEgypt

The asymptotic expansions of the trace of the heat kernel Θ(t) = Σ_(v =1)~∞exp(-tλ_v) for small positive t, where {λ_v} are the eigenvalues of the negative Laplacian-△_n = -Σ_(i = 1)~n(partial deriv/(partial deriv)x^i)~2 in R^n (n = 2 or 3), are studied for ageneral annular bounded domain Ω with a smooth inner boundary (partial deriv)Ω_1 and a smoothouter boundary (partial deriv)Ω_2, where a finite number of piecewise smooth Robin boundaryconditions (partial deriv/(partial deriv)n_j + γ_j)φ = 0 on the components Γ_j(j = 1, …, k) of(partial deriv)Ω_1 and on the components Γ_j(j = k + 1, …, m) of (partial deriv)Ω_2 areconsidered such that (partial deriv)Ω_1 = ∪_(j = 1)~kΓ_j and (partial deriv)Ω_2 = ∪_(j = k +1)~mΓ_j and where the coefficients γ_j(j = 1, …, m) are piecewise smooth positive functions. Someapplications of Θ(t) for an ideal gas enclosed in the general annular bounded domain Ω are *** results are also obtained.

关键词： inverse problem heat kernel eigenvalues Robin boundary conditions classical ideal gas