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Role of vascular endothelial growth factor as a critical neurotrophic factor for the survival and physiology of motoneurons

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Neural Regeneration Research 2023年第8期18卷 1691-1696页

作者： Paula m.Calvo Rosendo G.Hernández Rosa R.de la Cruz angel m.pastor Departamento de Fisiología Facultad de BiologíaUniversidad de SevillaSevillaSpain

Vascular endothelial growth factor(VEGF)was discovered by its angiogenic ***,during evolution,it appeared earlier as a neurotrophic factor required for the development of the nervous system in invertebrates lacking a circulatory *** aimed at reviewing recent evidence indicating that VEGF has neuroprotective effects in neurons exposed to a variety of *** particular interest is the link established between VEGF and motoneurons,especially after the design of the VEGFδ/δmutant *** mice are characterized by low levels of VEGF and develop muscle weakness and motoneuron degeneration resembling amyotrophic lateral *** administration of VEGF through several routes to animal models of amyotrophic lateral sclerosis delays motor impairment and motoneuron degeneration and increases life *** are new recent advances in the role of VEGF in the physiology of *** experimental aims use the extraocular(abducens)motoneurons lesioned by axotomy as a model for studying VEGF *** abducens motoneurons exhibit severe alterations in their discharge activity and a loss of synaptic *** exogenous administration of VEGF to axotomized abducens motoneurons,either from the transected nerve or intraventricularly,fully restores the synaptic and discharge properties of abducens motoneurons,despite being *** addition,when an anti-VEGF neutralizing antibody is delivered from the muscle to intact,uninjured abducens motoneurons,these cells display alterations in their discharge pattern and a loss of synaptic boutons that resemble the state of *** these data indicate that VEGF is an essential neurotrophic factor for motoneurons.

关键词： abducens nucleus amyotrophic lateral sclerosis cell death extracellular single-unit recordings eye movements neurodegeneration oculomotor trophic factors

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不可压缩塑性局部破坏问题的有效解法

岩土工程学报 1999年第1期21卷 108-110页

作者：刘晓青夏颂佑 m.pastor 河海大学水利水电工程学院西班牙公共试验研究中心

１前言对于不可压缩或近似不可压缩问题的求解通常采用混合位移－压力（ｕ－ｐ）公式［１，２］，但由于离散的控制方程中与压力项对应的系数矩阵的主对角元接近于零，ｕ，ｐ插值函数的选择受到Ｂａｂｕｓｋａ－Ｂｒｅｚｚｉ稳定条件或... 详细信息

１前言对于不可压缩或近似不可压缩问题的求解通常采用混合位移－压力（ｕ－ｐ）公式［１，２］，但由于离散的控制方程中与压力项对应的系数矩阵的主对角元接近于零，ｕ，ｐ插值函数的选择受到Ｂａｂｕｓｋａ－Ｂｒｅｚｚｉ稳定条件或Ｚｉｅｎｋｉｅｗｉｃｚ－Ｔａｙｌｏ...

关键词：不可压缩塑性破坏机理网络法稳定性

LevelSet方法求解三维大幅晃动问题的分步有限元法

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水动力学研究与进展（A辑） 2006年第4期21卷 433-438页

作者：赵兰浩李同春牛志伟 m.pastor 河海大学水利水电工程学院江苏南京210098 CEDEX and E.T.S.de Caminos MadridSpain

取与容器固结的坐标系,将外激励视为质量力,针对刚性容器内流体三维非线性大幅晃动问题,提出了在时间和空间上均具有二阶精度的两步Taylor-Galerk in分步有限元方法。该法首先显式地求解忽略压力梯度项的中间速度场,然后由压力泊松方程... 详细信息

取与容器固结的坐标系,将外激励视为质量力,针对刚性容器内流体三维非线性大幅晃动问题,提出了在时间和空间上均具有二阶精度的两步Taylor-Galerk in分步有限元方法。该法首先显式地求解忽略压力梯度项的中间速度场,然后由压力泊松方程求得压力场,再根据求得的压力对速度场进行修正。求解中利用Level-Set方法隐式地追踪自由面,即在每个时间步求解Level-Set函数随水流的输运方程,并通过迭代的方法对其进行重新初始化,以保持为距离的函数,从而达到捕捉自由面的目的。控制方程统一采用简单方便且具有较高精度的两步Taylor-Galerk in格式进行离散,并通过两个算例验证了本文数值方法的正确性和有效性。

关键词：大幅晃动 Level Set 两步Taylor—Galerkin 分步有限元

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刚性容器内流体非线性大幅晃动的数值模拟

河海大学学报（自然科学版） 2006年第4期34卷 401-405页

作者：赵兰浩李同春牛志伟 m.pastor 河海大学水利水电工程学院江苏南京210098 西班牙国家公共实验研究中心

取与容器固结的坐标系,将外激励视为质量力,针对刚性容器内流体非线性大幅晃动问题,提出了在时间和空间上均具有二阶精度的两步Taylor-Galerkin分步有限元方法.该方法首先显式地求解忽略压力梯度项的中间速度场,然后通过压力泊松方程求... 详细信息

取与容器固结的坐标系,将外激励视为质量力,针对刚性容器内流体非线性大幅晃动问题,提出了在时间和空间上均具有二阶精度的两步Taylor-Galerkin分步有限元方法.该方法首先显式地求解忽略压力梯度项的中间速度场,然后通过压力泊松方程求得压力场,最后根据求得的压力对速度场进行修正.求解中利用Level Set方法隐式地追踪自由面,即在每个时间步求解Level-Set函数随水流的输运方程,并通过迭代方法对其重新进行初始化处理,使其保持为距离的函数,从而达到捕捉自由面的目的.控制方程统一采用简便且具有较高精度的两步Taylor-Galerkin格式进行离散.算例验证结果表明,该数值方法是正确和有效的.

关键词：刚性容器大幅晃动 Level Set 两步Taylor-Galerkin 分步有限元法

microscopic theory of light-induced ultrafast skyrmion excitation in transition metal films

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npj Computational materials 2022年第1期8卷 598-604页

作者： Emil Viñas Boström angel Rubio Claudio Verdozzi max Planck Institute for the Structure and Dynamics of matter Luruper Chaussee 14922761HamburgGermany Center for Computational Quantum Physics(CCQ) The Flatiron Institute162 Fifth AvenueNew YorkNY10010USA Division of mathematical Physics and ETSF Lund UniversityPO Box 11822100LundSweden

magnetic skyrmions are topological excitations of great promise for compact and efficient memory ***,to interface skyrmionics with electronic devices requires efficient and reliable ways of creating and destroying such *** this work,we unravel the microscopic mechanism behind ultrafast skyrmion generation by femtosecond laser pulses in transition metal thin *** employ a theoretical approach based on a two-band electronic model,and show that by exciting the itinerant electronic subsystem with a femtosecond laser ultrafast skyrmion nucleation can occur on a 100 fs *** combining numerical simulations with an analytical treatment of the strong s–d exchange limit,we identify the coupling between electronic currents and the localized d-orbital spins,mediated via Rashba spin–orbit interactions among the itinerant electrons,as the microscopic and central mechanism leading to ultrafast skyrmion *** results show that an explicit treatment of itinerant electron dynamics is crucial to understand optical skyrmion generation.

关键词： excitation transition topological

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不排水固结问题的劈裂半显式交互解法

河海大学学报（自然科学版） 1998年第1期26卷 44-48页

作者：刘晓青 m.pastor 夏颂佑李同春河海大学水利水电工程学院

对不排水固结问题，由于受ＢａｂｕｓｋａＢｒｅｚｉ稳定条件限制，常规的有限元等插值ｕ—ｐ解法将不能给出正确的结果．本文提出的半显式交互解法可避免这一条件的限制，使得位移ｕ、压力ｐ的插值阶数保持一致．一个简单算例验证了... 详细信息

对不排水固结问题，由于受ＢａｂｕｓｋａＢｒｅｚｉ稳定条件限制，常规的有限元等插值ｕ—ｐ解法将不能给出正确的结果．本文提出的半显式交互解法可避免这一条件的限制，使得位移ｕ、压力ｐ的插值阶数保持一致．一个简单算例验证了本文方法的正确性．

关键词：不排水固结相互作用等插值函数地基排水

Systemic analysis of metabolome reconfiguration in Arabidopsis after abiotic stressors uncovers metabolites that modulate defense against pathogens

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Plant Communications 2024年第1期5卷 55-68页

作者： Antoni Garcia-molina Victoria pastor Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB C/Vall MorontaEdifici CRAG08193 Bellaterra(Cerdanyola del Valles)BarcelonaSpain Department of Biology Biochemistryand Natural SciencesSchool of Technology and Experimental SciencesUniversitat Jaume I12006 Castellode la PlanaSpain

Understanding plant immune responses is complex because of the high interdependence among biological processes in homeostatic ***,the integration of environmental cues causes network rewiring that interferes with defense ***,plants retain molecular signatures configured under abiotic stress periods to rapidly respond to recurrent stress,and these can alter *** changes imposed by abiotic stressors are persistent,although their impact on defense remains to be *** this study,we profiled metabolomes of Arabidopsis plants under several abiotic stress treatments applied individually or simultaneously to capture temporal trajectories in metabolite composition during adverse conditions and *** systemic analysis was performed to address the relevance of me-tabolome changes and extract central features to be tested in *** results demonstrate irreversibility in major fractions of metabolome changes as a general pattern in response to abiotic stress ***-tionalanalysisofmetabolomesandco-abundancenetworkspoints toconvergence inthereconfigurationof organic acid and secondary metabolite *** mutant lines for components related to these metabolic pathways showed altered defense capacities against different ***,our data suggest that sustained metabolome changes configured in adverse environments can act as mod-ulators of immune responses and provide evidence for a new layer of regulation in plant defense.

关键词： abiotic stress Arabidopsis biotic stress combinatorial stress metabolomics systems biology

“H_(2)-free” demethoxylation of guaiacol in subcritical water using Pt supported on N-doped carbon catalysts:A cost-effective strategy for biomass upgrading

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Journal of Energy Chemistry 2021年第7期30卷 377-385页

作者： Laura pastor-Pérez Wei Jin Juan J.Villora-Picó Qiang Wang m.mercedes pastor-Blas Antonio Sepúlveda-Escribano Tomas R.Reina Department of Chemical and Process Engineering University of SurreyGuildford GU27XHUnited Kingdom Laboratorio de materiales Avanzados Departamento de Química Inorgánica-Instituto Universitario de Materiales de AlicanteUniversidad de AlicanteApartado 99E-03080 AlicanteSpain College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083China

"H_(2)-free" HDO is a revolutionary route to circumvent the limitations of H_(2)-fed HDO reactors for biomass *** work demonstrates the viability of this economically appealing route when an adequate catalyst is ***,we have developed a new family of Pt catalysts supported on N-doped activated carbons for the H_(2)-free HDO process of *** N-donors have been used to tune the catalyst’s structural and electronic *** a general trend,the N-promoted samples are more selective towards oxygen-depleted *** best performing material,namely Pt/PANI-AC reached outstanding guaiacol conversion values-ca.75% at 300℃ while displaying reasonable stability for multiple recycling *** advanced performance is ascribed to the modified electronic and acid-base properties which favor guaiacol activation and C-O cleavage,as well as the excellent dispersion of the Pt nano particles.

关键词： Biomass upgrading N-doped carbon Pt HDO Guaiacol H_(2)-free

FRACTIONAL-STEP FINITE ELEmENT mETHOD FOR CALCULATION OF 3-D FREE SURFACE PROBLEm USING LEVEL SET mETHOD

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Journal of Hydrodynamics 2006年第6期18卷 742-747页

作者： ZHAO Lan-hao LI Tong-chun WANG Ling HERREROS m. I. pastor m. College of Water Conservancy and Hydropower Engineering Hohai University Naniing 210098 China Anhui Survey and Design Institute of Water Conservancy and Hydropower Hefei 230022 China CEDEX and E.T.S. de Caminos Madrid Spain

A two-step Taylor-Galerkin fractional-step finite element method, which is of second order accuracy in space and time, was proposed for the three-dimensional free surface problem. With this method, the intermediate velocity was explicitly obtained by neglecting pressure gradient term, and then the velocity was corrected by adding the effects of pressure once the pressure field had been obtained from the pressure Poisson equation. The level set approach was applied to track implicitly the free surface. In order to track the free surface, the transport equation of the level set function was solved at each time step and the level set function is reinitialized through iteration to maintain it as a distance function. The governing equations of the system were discretized by the two- step Taylor-Galerkin method, which is of high-order accuracy and easy to be used. The validity and reliability of this method in this article were proved by two numerical examples.

关键词： level set free surface two steps Taylor-Galerkin fractional step FEm