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neurocircuit regeneration by extracellular matrix reprogramm.n.

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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 Departm.n. of medicinal Chemistry University of WashingtonSeattleWAUSA Departm.n. of Chemistry University of WashingtonSeattleWAUSA Departm.n. of medicine University of Washington Medicine Diabetes InstituteSeattleWAUSA

The brain's extracellular matrix(ECm),which is comprised of protein and glycosam.n.glycan(GAG)scaffolds,constitutes 20%-40% of the hum.n.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 programm.n.

Acid-treated carbon nanotubes and their effects on mortar strength

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Frontiers of Structural and Civil Engineering 2016年第2期10卷 180-188页

作者： m. ELKASHEF K. WAnG m.n. ABOU-ZEID Civil Construction and Environmental Engineering Department Iowa State University Ames IA 50011-2151 USA Construction and Architectural Engineering Departm.n. The American University in Cairo Egypt

In the present study, multi-walled carbon nanotubes （mWCnTs） were treated in an acidic mixture solution, made with nitric and sulfuric acids in a ratio of 3：1 by volume. The durations of the treatm.n. were 100 and 180 m.n. The defects of these treated mWCnTs were exam.n.d using Ram.n.spectroscopy. The attachm.n. of hydroxyl functional groups to the walls of the mWCnTs were verified using FTIR spectroscopy. The dispersion of CnTs with acid treatm.n. is assessed using UV-Vis spectroscopy and Scanning Electron microscopy （SEm）. The results indicate that the duration of the acid treatm.n. has significant effect on both the degree of defects and functionality of the mWCnT. The compressive strength of mortar increased with the addition of the acid-treated mWCnTs; however, no appreciable difference was noted for the two treatm.n. durations under this study.

关键词： carbon nanotubes concrete composites nanomaterials cem.n.

LASER HEAT TREATInG RESEARCH OF THREE KInDS OF HIGH SPEED STEEL

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Acta metallurgica Sinica(English Letters) 1999年第5期12卷 757-760页

作者： Liu, W.n. Fang, m.n. Xing, J. Liu, Y.W. Changchun Inst of Optics and Fine Mechanics Changchun China

After laser quenching and tempering of three kinds of annealed tool high-speed steel(W18Cr-4V, W9mo3Cr4V1, W6mo5Cr4V2) test samples, the microhardness measurer was used to test the samples and some problems, such as the hardness and depth of hardening-quenching layer were analyzed. Furthermore, after laser quenching and tempering of the quenched and three-time tempered high-speed steel (W18Cr4V) and its hardness analyzing, different results of laser-quenching samples were obtained under different initial heat-treating.

关键词： Hardening Heat treatm.n. Laser beam effects microhardness Phase transitions Quenching

Column leaching of lanthanides from Abu Tartur phosphate ore with kinetic study

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Journal of Rare Earths 2010年第4期28卷 576-580页

作者： A.T. Kandil m.m. Aly E.m. moussa A.m. Kamel m.m. Gouda m.n. Kouraim Chemistry Departm.n. Faculty of Science Helwan University nuclear materials Authority P.O. Box 530 El Maadi Cairo Egypt

The dynamic leaching of lanthanides from a west desert phosphate ore, Egypt (Abu Tartur) by hydrochloric acid, nitric acid and sulfuric acid solutions was investigated in this study as a function of acid concentration, flow rate and the presence of some additives such as boric acid. Also the kinetics of leaching of lanthanides was investigated as a function of temperature. It was found that the leaching process could be described by a shrinking-core model, with activation energy about 5.9, 13.8 and 21.9 kJ/...

关键词： column leaching lanthanides Abu Tartur hydrochloric acid nitric acid sulfuric acid kinetics rare earths

Influence of thickness and projectile shape on penetration resistance of the compliant composite

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Defence Technology（防务技术） 2021年第1期17卷 245-256页

作者： Vishwas mahesh Sharnappa Joladarashi Satyabodh m.kulkarni Departm.n. of mechanical Engineering National Institute of Technology Karnataka SurathkalMangalore 575025India Departm.n. of Industrial Engineering and m.n.gem.n. Siddaganga Institute of TechnologyTumakuru 572103KarnatakaIndia

The present study deals with developm.n. of conceptual proof for jute rubber based flexible composite block to completely arrest the projectile impacting the target at high velocity impact of 400 m/s through numerical simulation approach using finite elem.n.(FE)*** proposed flexible composite blocks of repeating jute/rubber/jute(JRJ)units are modelled with varying thickness from 30 mm to 120 mm in increm.n.s of 30 mm and impacted by flat(F),ogival(O)and hemispherical(HS)shaped *** the considered projectiles are impacted with proposed flexible composite blocks of different thicknesses and the penetration behaviour of the projectile in each case is *** penetration depth of the projectile in case of partially penetrated cases are considered and the effect of thickness and projectile shape on percentage of penetration depth is statistically analyzed using Taguchi’s design of experim.n.s(DOE).Results reveal that the though proposed flexible composite block with thickness of 90 mm is just sufficient to arrest the complete penetration of the projectile,considering the safety issues,it is recomm.n.ed to use the flexible composite with thickness of 120 *** nature of damage caused by the projectile in the flexible composite is also *** studies show that thickness of the block plays a prom.n.nt role in determ.n.ng the damage resistance of the flexible composite.

关键词： Flexible composite blocks Jute Rubber High velocity Projectile shapes Thickness Damage resistance Penetration depth

Regulator of G protein signaling 6 mediates exercise-induced recovery of hippocampal neurogenesis,learning,and memory in a mouse model of Alzheimer’s disease

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neural Regeneration Research 2025年第10期20卷 2969-2981页

作者： mackenzie m.Spicer Jianqi Yang Daniel Fu Alison n.DeVore marisol Lauffer nilufer S.Atasoy Deniz Atasoy Rory A.Fisher Departm.n. of neuroscience and Pharmacology University of Iowa Carver College of MedicineIowa CityIAUSA Iowa neuroscience Institute University of Iowa Carver College of MedicineIowa CityIAUSA Interdisciplinary Graduate Program in molecular medicine University of Iowa Carver College of MedicineIowa CityIAUSA neural Circuits and Behavior Core University of Iowa Carver College of MedicineIowa CityIAUSA

Hippocampal neuronal loss causes cognitive dysfunction in Alzheimer’s *** hippocampal neurogenesis is reduced in patients with Alzheimer’s *** stimulates adult hippocampal neurogenesis in rodents and improves memory and slows cognitive decline in patients with Alzheimer’s ***,the molecular pathways for exercise-induced adult hippocampal neurogenesis and improved cognition in Alzheimer’s disease are poorly ***,regulator of G protein signaling 6(RGS6)was identified as the mediator of voluntary running-induced adult hippocampal neurogenesis in ***,we generated novel RGS6fl/fl;APP_(SWE) mice and used retroviral approaches to exam.n. the impact of RGS6 deletion from dentate gyrus neuronal progenitor cells on voluntary running-induced adult hippocampal neurogenesis and cognition in an amyloid-based Alzheimer’s disease mouse *** found that voluntary running in APP_(SWE) mice restored their hippocampal cognitive impairm.n.s to that of control *** cognitive rescue was abolished by RGS6 deletion in dentate gyrus neuronal progenitor cells,which also abolished running-mediated increases in adult hippocampal *** hippocampal neurogenesis was reduced in sedentary APP_(SWE) mice versus control mice,with basal adult hippocampal neurogenesis reduced by RGS6 deletion in dentate gyrus neural precursor ***6 was expressed in neurons within the dentate gyrus of patients with Alzheimer’s disease with significant loss of these RGS6-expressing ***,RGS6 mediated voluntary running-induced rescue of impaired cognition and adult hippocampal neurogenesis in APP_(SWE) mice,identifying RGS6 in dentate gyrus neural precursor cells as a possible therapeutic target in Alzheimer’s disease.

关键词： adult hippocampal neurogenesis Alzheimer’s disease dentate gyrus exercise learning/memory neural precursor cells regulator of G protein signaling 6(RGS6)

Damage mechanics and energy absorption capabilities of natural fiber reinforced elastomeric based bio composite for sacrificial structural applications

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Defence Technology（防务技术） 2021年第1期17卷 161-176页

作者： Vishwas mahesh Sharnappa Joladarashi Satyabodh m.kulkarni Departm.n. of mechanical Engineering National Institute of Technology Karnataka SurathkalMangalore575025India

The present study deals with the experim.n.al,finite elem.n.(FE)and analytical assessm.n. of low ballistic impact response of proposed flexible‘green’composite make use of naturally available jute and rubber as the constituents of the composite with stacking sequences namely jute/rubber/jute(JRJ),jute/rubber/rubber/jute(JRRJ)and jute/rubber/jute/rubber/jute(JRJRJ).Ballistic impact tests were carried out by firing a conical projectile using a gas gun apparatus at lower range of ballistic impact *** ballistic impact response of the proposed flexible composites are assesses based on energy absorption and damage *** revealed that inclusion of natural rubber aids in better energy absorption and mitigating the failure of the proposed *** the three different stacking sequences of flexible composites considered,JRJRJ provides better ballistic perform.n.e compared to its *** damage study reveals that the main mechanism of failure involved in flexible composites is matrix tearing as opposed to matrix cracking in stiff composites indicating that the proposed flexible composites are free from catastrophic *** obtained from experim.n.al,FE and analytical approach pertaining to energy absorption and damage mechanism agree well with each *** proposed flexible composites due to their exhibited energy absorption capabilities and damage mechanism are best suited as claddings for structural application subjected to impact with an aim of protecting the main structural component from being failed catastrophically.

关键词： Flexible composite Ballistic impact Energy absorbed Rubber Damage mechanism

A comprehensive review on material selection for polymer matrix composites subjected to impact load

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Defence Technology（防务技术） 2021年第1期17卷 257-277页

作者： Vishwas mahesh Sharnappa Joladarashi Satyabodh m.kulkarni Departm.n. of mechanical Engineering National Institute of Technology Karnataka SurathkalMangalore575025India

Polymer matrix composites(PmC)are extensively been used in m.n. engineering *** natural fibers have emerged as potential replacem.n.s to synthetic fibers as reinforcing materials composites owing to their fairly better mechanical properties,low cost,environm.n. friendliness and *** of appropriate constituents of composites for a particular application is a tedious task for a designer/*** loading has emerged as the serious threat for the composites used in structural or secondary structural application and dem.n.s the usage of appropriate fiber and matrix combination to enhance the energy absorption and mitigate the *** objective of the present review is to explore the composite with various fiber and matrix combination used for impact applications,identify the gap in the literature and suggest the potential naturally available fiber and matrix combination of composites for future work in the field of impact *** novelty of the present study lies in exploring the combination of naturally available fiber and matrix combination which can help in better energy absorption and mitigate the failure when subjected to impact *** addition,the application of multi attributes decision making(mADm)tools is dem.n.trated for selection of fiber and matrix materials which can serve as a benchmark study for the researchers in future.

关键词： Polymer matrix composites natural fibers Green composite Impact characterization Flexible composite mADm Approach

Surface-effects-dom.n.ted thermal and mechanical responses of zinc oxide nanobelts

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Acta mechanica Sinica 2006年第3期22卷 217-224页

作者： A. J. kulkarni. m. Zhou The George W. Woodruff School of mechanical Engineering Georgia Institute of Technology Atlanta Georgia

t molecular dynamics （mD） simulations are carried out to characterize the mechanical and thermal responses of [011^-1]-oriented ZnO nanobelts with lateral dim.n.ions of 21.22A × 18.95 A, 31.02A× 29.42 A, and40.81A ×39.89A over the temperature range of 300-1000 K. The Young＇s modulus and thermal conductivity of the nanobelts are evaluated. Significant surface effects on properties due to the highsurface-to-volume ratios of the nanobelts are observed. For the mechanical response, surface-stress-induced internal stress plays an important role. For the thermal response, surface scattering of phonons dom.n.tes. Calculations show that the Young＇s modulus is higher than the corresponding value for bulk ZnO and decreases by -33% as the lateral dim.n.ions increase from 21.22 A × 18.95A to 40.81 A × 39.89A. The thermal conductivity is one order of magnitude lower than the corresponding value for bulk ZnO single crystal and decreases with wire size. Specifically, the conductivity of the 21.22 A × 18.95 A belt is approximately （31-18）% lower than that of the 40.81 A × 39.89 A belt over the temperature range analyzed. A significant dependence of properties on temperature is also observed, with the Young＇s modulus decreasing on average by 12% and the conductivity decreasing by 50% as temperature increases from 300 K to 1000 K.

关键词： Zinc oxide nanobelts Surface effects Size dependence Young's modulus Thermal conductivity