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Neurocircuit regeneration by extracellular matrix reprogramming

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Neural Regeneration Research 2025年第8期20卷 2300-2301页

作者： Shengzhang Su Ian N.Levasseur Kimberly m.Alonge Department of medicinal Chemistry University of WashingtonSeattleWAUSA Department of Chemistry University of WashingtonSeattleWAUSA Department of medicine University of Washington Medicine Diabetes InstituteSeattleWAUSA

The brain's extracellular matrix(eCm),which is comprised of protein and glycosaminoglycan(GAG)scaffolds,constitutes 20%-40% of the human brain and is considered one of the largest influencers on brain cell functioning(Soles et al.,2023).Synthesized by neural and glial cells,the brain's eCm regulates a myriad of homeostatic cellular processes,including neuronal plasticity and firing(miyata et al.,2012),cation buffering(moraws ki et al.,2015),and glia-neuron interactions(Anderson et al.,2016).Considering the diversity of functions,dynamic remodeling of the brain's eCm indicates that this understudied medium is an active participant in both normal physiology and neurological diseases.

关键词： matrix programming

DNA Dynamics Studied Using the Homogeneous Balance method

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Chinese Physics Letters 2012年第8期29卷 9-11页

作者： e.m.e.Zayed A.H.Arnous mathematics Department Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

We employ the homogeneous balance method to construct the traveling waves of the nonlinear vibrational dynamics modeling of *** new explicit forms of traveling waves are *** is shown that this method provides us with a powerful mathematical tool for solving nonlinear evolution equations in mathematical *** and weaknesses of the proposed method are discussed.

关键词： traveling nonlinear method

The Asymptotics of the Heat Semigroup for a General Bounded Domain with mixed Boundary Conditions

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Acta mathematica Sinica,english Series 2000年第4期16卷 627-636页

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

Small-time asymptotics of the trace of the heat semigroup θ（t）=Σv=1x exp（-tμv）. where {μv} are the eigenvalues of the uegative Laplacian -Δ= -Σβ=12（/xβ）2 in the （x1, x2）-plane. is studied for a general bounded domain Ω with a smooth boundary Ω. where a finite number of Dirichlet. Neumann and Robin boundary conditions, on the piecewise smooth parts Γi（i=1, ..., n） of )Ω such that)Ω=∪i=1nΓ are considered. Some geometrical properties associated with Ω are determined

关键词： Heat semigroup Inverse problem mixed boundary conditions eigenvalues

Structural,morphological and optical properties of new eu-doped and vacancied lead molybdato-tungstates

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Journal of Rare earths 2018年第6期36卷 635-641页

作者： m.Piotkowska e.Tomaszewicz Faculty of Chemical Technology and engineering Department of Inorganic and Analytical ChemistryWest Pomeranian University of TechnologySzczecinAI.Piast6w 4271-065 SzczecinPoland

A new tetragonal,scheelite-type Pb_(1-3 x)■_xeU_(2 x)(moO_4)_(1-3 x)(WO_4)_(3 x)(0 3 eV) and their band gap nonlinearly decreases with increasing dopant concentration.

A new tetragonal,scheelite-type Pb_(1-3 x)■_xeU_(2 x)(moO_4)_(1-3 x)(WO_4)_(3 x)(0enotes A-site vacancies) solid solution was synthesized via solid state reaction method. The X-ray diffraction(XRD) and scanning electron microscopy(Sem) results confirm the formation of single, tetragonal scheelite-type phases(space group I4_1/a) with the average crystallite size in the range of ～20-100 μm. Substitution of Pb^(2+) with eu^(3+) is relatively easy despite the large difference in ionic radii, and the formation of vacancies is necessary to compensate the excess positive charge in PbmoO_4 framework. A change in lattice parameters(both a and c as well as lattice parameter ratio c/a) and progressive deformation of moO_4 and WO_4 tetrahedra with increasing eu concentration are observed. Thermal stability of eu-doped materials strongly depends on the concentration of eu3+ ions. The Pb_(1-3 x)■_xeu_(2 x)(moO_4)_(1-3 x)(WO_4)_(3 x) solid solution for x=0.0098 shows the highest melting point(1057 ℃) which is slightly higher than that of pure PbmoO_4(1040 ℃). The UV-vis diffuse reflectance spectroscopy(DRS) and the Tauc plots were used to extrapolate the optical indirect band gap(e_g) of doped materials. eu-doped ceramics are insulators(e_g > 3 eV) and their band gap nonlinearly decreases with increasing dopant concentration.

关键词： molybdato-tungstate Scheelites Thermal stability Optical properties Rare earths

mechanical, electrical, and thermal properties of the directionally solidified Bi–Zn–Al ternary eutectic alloy

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International Journal of minerals,metallurgy and materials 2014年第10期21卷 999-1008页

作者： m.Sahin e.adrli Department of electronics and Automation Technical Vocational School of Sciences Nigde University Department of Physics Faculty of Arts and Sciences Nigde University

A Bi-2.0Zn-0.2A1 （wt%） ternary eutectic alloy was prepared using a vacuum melting furnace and a casting furnace. The samples were directionally solidified upwards at a constant growth rate （V= 18.4 μm/s） under different temperature gradients （G = 1.15-3.44 K/mm） and at a constant temperature gradient （G = 2.66 K/mm） under different growth rates （V= 8.3-500 μm/s） in a Bridgman-type directional so- lidification furnace. The dependence ofmicrostructure parameter （2） on the solidification parameters （G and V） and that of the microhardness （Hv） on the microstructure and solidification parameters were investigated. The resistivity （ρ） measurements of the studied alloy were per- formed using the standard four-point-probe method, and the temperature coefficient of resistivity （α） was calculated from the ρ-Tcurve. The enthalpy （AH） and the specific heat （Cp） values were determined by differential scanning calorimetry analysis. In addition, the thermal conductivities of samples, obtained using the Wiedemann-Franz and Smith-Palmer equations, were compared with the experimental results. The results revealed that, the thermal conductivity values obtained using the Wiedemarm-Franz and Smith-Palmer equations for the Bi-2.0Zn-0.2Al （wt%） alloy are in the range of 5.2-6.5 W/Km and 15.2-16.4 W/Km, respectively.

关键词： ternary eutectic alloys directional solidification microhardness electrical resistivity thermal conductivity

FIRST-ORDeR meTHODS FOR SOLVING THe OPTImAL STATIC H∞-SYNTHeSIS PROBLem

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Journal of Computational mathematics 2007年第6期25卷 672-689页

作者： el-Sayed m.e. mostafa Department of mathematics Faculty of Science Alexandria University Alexandria Egypt

In this paper, we consider the static output feedback （SOF） H∞-synthesis problem posed as a nonlinear semi-definite programming （NSDP） problem. Two numerical algorithms are developed to tackle the NSDP problem by solving the corresponding Karush- Kuhn-Tucker first-order necessary optimality conditions iteratively. Numerical results for various benchmark problems illustrating the performance of the proposed methods are given.

关键词： Static output feedback H∞-synthesis Semi-definite programming Nonlinear programming.

Plasma ignition threshold disparity between silver nanoparticle-based target and bulk silver target at different laser wavelengths

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Plasma Science and Technology 2019年第1期21卷 63-71页

作者： A m eL SHeRBINI m m HAGRASS m R m RIZK e A eL-BADAWY Laboratory of Laser and New materials Faculty of Science Cairo University Faculty of engineering Electrical Engineering Department Alexandria University

Plasma ignition threshold of nanoparticle-based and bulk silver targets was measured in air. The plasma was initiated by a Nd:YAG laser at wavelengths of 355, 532, and 1064 nm. The plasma ignition was monitored utilizing the prominent Ag I line at 546.5 nm. Lower ignition thresholds of the nanoparticle-based silver target were estimated at 0.4?±?0.02, 0.34?±?0.04, and 0.27?±?0.035 J cm^(-2) coupled with the different laser wavelengths, respectively. In contrast, the bulk silver target plasma exhibited an order of magnitude higher ignition threshold. A three orders of magnitude enhanced emission intensity from the nano-based target over the bulk target was achieved at lower levels of laser irradiation. A reduction of the thermal diffusion length of the nanosilver was assumed in order to theoretically predict this reduction in the plasma threshold. In addition, the effect of self-reversal on the resonance lines was taken into consideration.

关键词： NeLIBS enhancement nanosilver laser plasma threshold

Ion-acoustic waves at the night side of Titan's ionosphere:higher-order approximation

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Communications in Theoretical Physics 2020年第5期72卷 70-77页

作者： S m Ahmed e R Hassib U m Abdelsalam R e Tolba W m moslem Department of mathematics Faculty of ScienceSuez UniversitySuezEgypt Department of mathematics Faculty of ScienceFayoum UniversityFayoumEgypt Department of mathematics Rustaq College of EducationOman Centre for Theoretical Physics The British University in Egypt(BUE)El-Shorouk CityCairoEgypt Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt

Nonlinear solitary waves are investigated for a plasma system at the night side of Titan's *** plasma model consists of three positive ions,namely C2H5^+,HCNH^+,and C3H5^+,as well as maxwellian *** basic set of fluid equations is reduced to a Korteweg de-Vries(KdV)equation and linear inhomogeneous higher order KdV(LIHO-KdV)*** solitary wave solutions of both equations are obtained using a renormalization *** solitary waves'existence region and the wave profile are investigated,and their dependences on the plasma parameters at the night side of Titan's ionosphere are *** solitary waves'phase velocities are subsonic or supersonic,and the propagating pulses are usually *** effect of higher-order corrections on the perturbation theory is *** is found that the higher-order contribution makes the amplitude slightly taller,which is suitable for describing the solitary waves when the amplitude augments.

关键词： plasmas ion-acoustic waves planets and satellites:atmospheres

experimental approaches and analytical technique for determining heavy metals in fallen dust at ferrosilicon production factory in edfu, Aswan,egypt

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第8期6卷 708-718页

作者： SOLTAN m.e RAGeH H.m RAGeH N.m AHmeD m.e Department of Chemistry Faculty of Science at Aswan South Valley UniversityEgypt Department of Chemistry Faculty of Science at Qena South Valley UniversityEgyptDepartment of Chemistry Faculty of Science at Qena South Valley UniversityEgyptDepartment of Environment Egyptian Ferroalloy Edfu AswanEgypt

In this study aimed to evaluate the pollution extent of metals and nonmetals inside and outside the ferrosilicon production factory in edfu, Aswan, egypt, raw materials (quartz, cokes, iron oxides), ferrosilicon alloy, silica fume, dust and suspended dust (at different sites) samples were collected from the factory, and fallen dust samples were collected from outside the factory, horizontally (at different sites and different distance and directions) and vertically (at different floors in the selected buildings). Gravimetric methods, X-ray fluorescence (XRF), flame photometer, wide range carbon determinator and atomic absorption spectroscopy tools were used for elements determination. The results indicating that the fallen dust and its element contents on southern factory walls being higher than those on eastern factory walls may be due to the nature of the dusts and effects of wind force and wind direction. Fallen dust levels in different regions outside the factory were found to be affected by the distance, direction and floors. The nature of dust samples was affected by gravity and the suspended dust in different factory units depended on the work capacity and method of handling materials by personnel in different production units. Silica fume was a complicated problem, had dangerous effect against the workers' health, and was characterized by high concentrations of SiO2(90.6%～93.6%) and heavy metals (mn, 420.6×10-6～520.3×10-6; Fe, 2354×10-6～2685×10-6; Co, 80.7×10-6～101.6×10 6 and Ni,5.3× 10-6～6.05× 10-6). The TSP (Total Suspended Particulate) levels in all factory units were higher than the recommended air quality value (70 μg/m3) under egyptian law. The effect of ferrosilicon factory fallen dust on the surrounding regions decreased with increasing distance between the factory and these regions. The suspended dust samples in the factory units and their components greatly exceeded national and international standards, so health and environmental criteria must be

关键词： Air pollution Dust Heavy metals Fallen dust