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Dendritic spine density changes and homeostatic synaptic scaling:a meta-analysis of animal studies

Neural Regeneration Research 2022年第1期17卷 20-24页

作者： Thiago C.Moulin Danielle Rayêe Helgi b.schiöth Functional Pharmacology Unit Department of NeuroscienceUppsala UniversityUppsalaSweden Institute of Medical biochemistry Federal University of Rio de JaneiroRio de JaneiroBrazil Institute of biomedical sciences Federal University of Rio de JaneiroRio de JaneiroBrazil Department of Ophthalmology and Visual sciences Albert Einstein College of MedicineNYUSA Institute for Translational Medicine and biotechnology Sechenov First Moscow State Medical UniversityMoscowRussia

Mechanisms of homeostatic plasticity promote compensatory changes of cellular excitability in response to chronic changes in the network *** type of plasticity is essential for the maintenance of brain circuits and is involved in the regulation of neural regeneration and the progress of neurodegenerative *** of the most studied homeostatic processes is synaptic scaling,where global synaptic adjustments take place to restore the neuronal firing rate to a physiological range by the modulation of synaptic receptors,neurotransmitters,and ***,despite the comprehensive literature on the electrophysiological properties of homeostatic scaling,less is known about the structural adjustments that occur in the synapses and dendritic *** this study,we performed a meta-analysis of articles investigating the effects of chronic network excitation(synaptic downscaling)or inhibition(synaptic upscaling)on the dendritic spine density of *** results indicate that spine density is consistently reduced after protocols that induce synaptic scaling,independent of the intervention ***,we discuss the implication of our findings to the current knowledge on the morphological changes induced by homeostatic plasticity.

关键词： chronic inhibition chronic stimulation dendritic spines downscaling excitability homeostatic plasticity spine density synaptic scaling upscaling

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化学沉积法制备的Ni(P)、Ni(b)纳米薄膜的结构与磁性

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材料导报 2002年第9期16卷 69-71页

作者：章建高 b.N.斯捷琴科 s.D.安提波夫 G.E.哥留诺夫华南师范大学物理系广州510631 国立莫斯科大学物理系

用化学沉积法制备了系列Ni(P)、Ni(b)合金薄膜样品。用X射线衍射结构分析方法证明样品由尺寸为纳米量级的颗粒组成。样品在磁性上表现出超顺磁性。对热磁处理前后的磁学参数进行了比较研究。

关键词：化学沉积法制备纳米薄膜磁性材料超顺磁性镍磷合金镍硼合金

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ENERGY sTORAGE IN METAL DEVICEs AND THE ADVANTAGEs OF LIQUID HYDROGENTEMPERATUREs

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Acta Metallurgica sinica(English Letters) 1997年第3期10卷 277-279,28-282页

作者： VR. sobolO.N MazurenkoA.A. Drozd and b.b. boiko(Institute of solid state and semiconductor Physics Asb, P. brovka str., 17, 220072 Minsk, belarus) Inst of solid state and Semiconductor Physics Minsk Belarus

Peculiarities of low temperature charge transport and enerpy accumulation in alu-minum devices are investigated by means of study of cylindrical conductors having a rudial cuerent fiow between inner and outer concentric contracts. Azimuthal current and, connected with it, self magnetic field are investigated in a wide range of radial current density up to 6000 A/cm2 under an external magnetic field up to 8 T Electron scattering processes are investigated and it is shown that relaxation electron mechanisms are determined by strong temperature dependence on account of high sus-ceptibility of scattering to anisotropy of electron dispersion law. The role of thermal phonons is investigated through an effective averaged conductivity tensor of polycrystalline medium. Using data of self magnetic self distribution on sample surface an energy density of self magnetic field is estimated. It is shown that at T=4.2 K average energy of self field may achieve at least 1 J/cm3. Using data of relaxation processes at temperature of liquid hydrogen it is established that self magnetic field must be a third of helium magnitude with respective self magnetic enengy density, spiral motion of carriers in this geometry being regarded as a current coils in usual inductive element.

关键词： energy storage charge transport magnetic field anisotropy

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A comprehensive study for mass attenuation coefficients of different parts of the human body through Monte Carlo methods

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Nuclear science and Techniques 2016年第3期27卷 31-39页

作者： E.E.Ermis F.b.Pilicer E.Pilicer C.Celiktas Physics Department Faculty of ScienceEge University Physics Department Faculty of Arts and ScienceUludag University

The gamma-ray mass attenuation coefficients of blood,bone,lung,eye lens,adipose,tissue,muscle,brain and skin were calculated at different energies(60,80,150,400,500,600,1000,1250,1500,and 2000 keV) by various theoretical methods such as FLUKA,GEANT4 Monte Carlo(MC) methods and XCOM program in this *** coefficients were also compared with the National Institute of standards and Technology(NIsT) *** results were highly in accordance with each other and NIsT *** results showed that FLUKA was quite convenient in comparison to GEANT4 in the calculation of the mass attenuation coefficients of the used human body samples for low-energy photons(60,80,and 150 keV) when compared with the NIsT values.

关键词：质量衰减系数蒙特卡洛方法 Geant4 部位 NIsT 美国国家标准能量计算眼晶状体

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Effects of dealloying and heat treatment parameters on microstructures of nanoporous Pd

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Journal of Materials science & Technology 2020年第13期47卷 123-129页

作者： Y.Z.Chen X.Y.Ma W.X.Zhang H.Dong G.b.shan Y.b.Cong C.Li C.L.Yang F.Liu state Key Lab.of solidification Processing Northwestern Polytechnical University710072 Xi’anChina

Microstructures of nanoporous Pd are essentially important for its physical and chemical *** this work,we show that the microstructures of nanoporous Pd can be tuned by adjusting compositions of the precursor alloys,and dealloying and heat treatment *** the ligament and pore sizes decrease with increasing the electrochemical potential upon dealloying and the concentration of noble component in the precursor *** treatment causes coarsening of the nanoporous *** a critical temperature,the nanoporous structures are subjected to significant *** the critical temperature,surface diffusion is believed to dominate the coarsening *** the critical temperature,the nanoporous structure coarsens remarkably at a rather high rate,which is ascribed to a multiple-mechanism controlled process.

关键词： Nanoporous metals Microstructure Dealloying Kinetics Coarsening

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High-Throughput Phenotyping of Dynamic Canopy Traits Associated with stay-Green in Grain sorghum

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Plant Phenomics 2020年第1期2卷 269-278页

作者： J.D.Liedtke C.H.Hunt b.George-Jaeggli K.Laws J.Watson A.b.Potgieter A.Cruickshank D.R.Jordan University of Hohenheim 70593 StuttgartGermany Agri-science Queensland Department of Agriculture and FisheriesWarwickQLD 4370Australia Queensland Alliance for Agriculture and Food Innovation The University of QueenslandWarwickQLD 4370Australia Queensland Alliance for Agriculture and Food Innovation The University of QueenslandGatton CampusToowoomba QLD 4343Australia

Drought is a recurring phenomenon that puts crop yields at risk and threatens the livelihoods of many people around the ***-green is a drought adaption phenotype found in sorghum and other *** expressing this phenotype show less drought-induced senescence and maintain functional green leaves for longer when water limitation occurs during grain fill,conferring benefits in both yield per se and *** physiological causes of the phenotype are postulated to be water saving through mechanisms such as reduced canopy size or access to extra water through mechanisms such as deeper *** sorghum breeding programs,stay-green has traditionally been assessed by comparing visual scores of leaf senescence either by identifying final leaf senescence or by estimating rate of leaf *** this study,we compared measurements of canopy dynamics obtained from remote sensing on two sorghum breeding trials to stay-green values(breeding values)obtained from visual leaf senescence ratings in multienvironment breeding trials to determine which components of canopy development were most closely linked to the stay-green ***,canopy size as estimated using preflowering canopy parameters was weakly correlated with stay-green values for leaf senescence while postflowering canopy parameters showed a much stronger association with leaf *** study suggests that factors other than canopy size have an important role in the expression of a stay-green phenotype in grain sorghum and further that the use of UAVs with multispectral sensors provides an excellent way of measuring canopy traits of hundreds of plots grown in large field trials.

关键词： breeding drought hundreds

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Clinical potential of tensionlengthening strategies during nerve repair

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Neural Regeneration Research 2022年第4期17卷 779-780页

作者： stanley bazarek Justin M.brown sameer b.shah Department of Neurosurgery Massachusetts General Hospital/Harvard Medical SchoolBostonMAUSA Department of Neurosurgery Brigham&Women’s Hospital/Harvard Medical SchoolBostonMAUSA Departments of Orthopedic surgery and bioengineering University of California-San DiegoLa JollaCAUSA

A(very)brief history of tension in nerve repair:successful nerve repair is achieved by conveying as many axons successfully to their targets as ***,this is best achieved through a direct end-to-end repair under minimal tension(Millesi,1986).However,this is not feasible in most cases of trauma,where a segment of tissue damage must be excised and *** has most commonly been addressed with the use of nerve grafts to bridge the *** nerve grafts are considered the gold standard,with allograft or synthetic substitutes demonstrating some success over shorter *** their utility,autologous grafts pose challenges of their *** include functional deficit in the donor distribution(typically sensory),extended operative duration,additional scarring,and a lack of intrinsic blood *** are also a poor anatomical match for the stumps being bridged,both internally(disparate neuronal size and composition)as well as externally(often requiring cabled bundles to approximate the caliber of the nerve being repaired).Finally,unlike end-to-end repairs,autologous grafts also require axons to traverse a second repair interface,where a large proportion of axons are lost across the anatomical discontinuity.

关键词： tension repair overcome

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Rheology and lubricity characteristics study at different temperatures using synthesized snO_(2) nanoparticles in KCl free bentonite water base mud

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Petroleum Research 2023年第4期8卷 541-549页

作者： A.b.M.Ariful bari Khandaker Nayem Ahmed Md saiful Alam Department of Petroleum and Mining Engineering Shahjalal University of Science and TechnologySylhet3114Bangladesh Department of Petroleum and Mining Engineering Jashore University of Science and TechnologyJashore7408Bangladesh

Drilling mud is a major concerning element due to its high operational and economic impact on the drilling *** additives are introduced to enhance the efficiency of drilling fluid,but none of them could perfectly achieve their proposed efficacy in drilling *** conceived several nanoparticles(NPs)in drilling fluid to dissolve this *** a singular instance,commercial tin oxide(snO_(2))nanoparticles were utilized to analyze the influence of NPs on the rheological and filtration properties of inorganic KCl salt-based drilling ***,the effect of snO_(2) NPs on mud lubricity characteristics is not studied ***,due to the hazardous behavior of KCl,its use is very ***,we consider a KCl-free bentonite water-based mud to avoid any environmental damages from drilling *** also use snO_(2) NPs that is synthesized in our laboratory by co-precipitation *** addition to rheological and filtration properties,we also investigate the effect of NPs on mud's lubricity that was not considered in the previous *** fluid properties are measured at five different NPs concentrations of 0.10,0.25,0.50,0.75&1.0 wt%,and at six different temperatures of 30,40,50,60,70,and 80°C,while filtration properties are measured using API low-pressure low temperature(LPLT)*** addition of 0.1 wt%snO_(2) NPs increases plastic viscosity,yield point,10 s gel strength,and 10 min gel strength by 10%,63%,20%,and 14%,*** maximum reduction in lubricity coefficient is found to be 14%at NPs concentration of 1.0 wt%.The NPs concentration of 0.5 wt%yielded a reduction in fluid loss and mud cake thickness by 8.1%and 34%,*** study suggests that snO_(2) NPs can be employed as an additive to improve the rheology,lubricity,and filtration properties of KCl-free bentonite water-based drilling mud.

关键词： Mud Rheology Lubricity Tin oxide Nanoparticles KCl

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Fully analytical evaluation of optical gain coefficient in bulk semiconductors in quasi-equilibrium free-carrier approximation

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Chinese Optics Letters 2014年第8期12卷 52-54页

作者： b.A.Mamedov Department of Physics Faculty of Arts and SciencesGaziosmanpas University

In this letter, a new analytical method is presented to calculate of the semiconductor optical gain coefficient. This method is particularly suitable for theoretical analyses to determine the dependence of semiconductor gain on the total carrier density and temperature in the semiconductor lasers. Also, the optical gain functions for semiconductor optical gain coefficient are presented analytically. The analytical evaluation is verified with numerical methods, which illustrates the accuracy of these obtained analytical expressions.

关键词： 140.0140 Lasers and laser optics 140.3380 Laser materials 140.5960 semiconductor lasers 080.1753 Computation methods

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Dynamical analysis and anti-synchronization of a new 6D model with self-excited attractors

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Applied Mathematics(A Journal of Chinese Universities) 2023年第1期38卷 27-43页

作者： saad Fawzi Al-Azzawi Ahmed s.Al-Obeidi Department of Mathematics College of Computer Science and MathematicsUniversity of MosulMosul 41002Iraq

A novel 6D dissipative model with an unstable equilibrium point is introduced *** of the dynamic characteristics of the proposed model were explored via analyses and numerical simulations including critical points,stability,Lyapunov exponents,time phase portraits,and circuit ***,anti-synchronization phenomena were implemented on the new ***,the error dynamics is ***,four different controllers are adopted to stabilize this error relying on the nonlinear control technique with two main ways:linearization and Lyapunov stability *** comparison with previous works,the present controllers realize anti-synchronization based on another method/linearization ***,a comparison between the two ways was *** simulation results show the effectiveness and accuracy of the first analytical strategy.

关键词： 6D hyperchaotic system self-excited attractor anti-synchronization Lyapunov stability theory

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