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MR定量肺灌注成像的高时间与空间分辨率两种序列应用于先天性膈疝修补术后2岁儿童的比较研究

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国际医学放射学杂志 2014年第6期 605-605页

作者： M.Weidner f.g.zllner C.Hagelstein K.zahn T.Schaible S.O.Schoenberg 刘晨 Institute of Clinical Radiology and Nuclear Medicine University Medical Center MannheimMedical Faculty MannheimHeidelberg UniversityTheodor-Kutzer Ufer 1-368167 MannheimGermany

摘要目的先天性膈疝(CDH)通常会导致肺发育不良。动态对比增强MRI(DCE-MRI)肺灌注成像可以进行定量研究,同时MR灌注的数值则取决于时间分辨率。因此本研究

关键词：膈疝修补术序列 MR 肺灌注成像儿童空间分辨率空间分辨力

2岁儿童先天性膈疝修补术后的3.0TMR定量肺灌注成像:初步研究

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国际医学放射学杂志 2013年第1期 98-98页

作者： f.g.zllner K.zahn T.Schaible S.O.Schoenberg L.R.Schad K.W.Neff 范文骏 Computer Assisted Clinical Medicine Medical Faculty MannheimHeidelberg UniversityTheodor-Kutzer-Ufer 1-368167 MannheimGermany

目的探讨先天性膈疝修补术后的2岁儿童行肺部3.0T动态对比增强MRI检查的可行性,以及该检查能否显示可能伴发的肺发育不良(表现为局部微循环减低)。方法选取12个膈疝修补术后儿童[平均年龄(2.0±0.2)岁]进行3.0T动态对比增强MRI检查,采... 详细信息

目的探讨先天性膈疝修补术后的2岁儿童行肺部3.0T动态对比增强MRI检查的可行性,以及该检查能否显示可能伴发的肺发育不良(表现为局部微循环减低)。方法选取12个膈疝修补术后儿童[平均年龄(2.0±0.2)岁]进行3.0T动态对比增强MRI检查,采用高时间分辨力的随机投影(TWIST)MRA序列。采用逐体素反卷积方式定量分析肺灌注情况。在避开大的肺内动静脉的情况下,分别选取6个感兴趣区(左右肺的上中下部)来评价肺血流量(PBf)、肺血容量(PBV)和平均通过时间(MTT)的情况。结果膈疝同侧和对侧的PBf和PBV值间的差异均具有统计学意义(Pf值明显低于对侧,提示肺灌注减低。先天性膈疝修补术后儿童的肺动态对比增强MRI检查有助于早期确定肺发育不良,并可进行长期随访观察。

关键词：膈疝修补术 MRI 儿童肺灌注 PBf

Targeting epigenetic mechanisms in amyloid-β-mediated Alzheimer’s pathophysiology:unveiling therapeutic potential

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Neural Regeneration Research 2025年第1期20卷 54-66页

作者： Jennie z.Li Nagendran Ramalingam Shaomin Li Ann Romney Center for Neurologic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alzheimer’s disease is a prominent chronic neurodegenerative condition characterized by a gradual decline in memory leading to *** evidence suggests that Alzheimer’s disease is associated with accumulating various amyloid-βoligomers in the brain,influenced by complex genetic and environmental *** memory and cognitive deficits observed during the prodromal and mild cognitive impairment phases of Alzheimer’s disease are believed to primarily result from synaptic *** life,environmental factors can lead to enduring changes in gene expression and the emergence of brain *** changes,known as epigenetic modifications,also play a crucial role in regulating the formation of synapses and their adaptability in response to neuronal *** this context,we highlight recent advances in understanding the roles played by key components of the epigenetic machinery,specifically DNA methylation,histone modification,and microRNAs,in the development of Alzheimer’s disease,synaptic function,and activity-dependent synaptic ***,we explore various strategies,including enriched environments,exposure to non-invasive brain stimulation,and the use of pharmacological agents,aimed at improving synaptic function and enhancing long-term potentiation,a process integral to epigenetic ***,we deliberate on the development of effective epigenetic agents and safe therapeutic approaches for managing Alzheimer’s *** suggest that addressing Alzheimer’s disease may require distinct tailored epigenetic drugs targeting different disease stages or pathways rather than relying on a single drug.

关键词： Alzheimer’s disease DNA methylation enriched environments histone modification microRNAs non-invasive brain stimulation synaptic plasticity

Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN T.ASgHAR z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both fick's and fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

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An SPH framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Advances in the treatment of autism spectrum disorder:Wharton jelly mesenchymal stem cell transplantation

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World Journal of Methodology 2025年第1期15卷 72-79页

作者： Serdar Kabatas ErdinçCivelek Eyüp Can Savrunlu Umut Karaaslan Özlem Yıldız Erdal Karaöz Department of Neurosurgery University of Health Sciences TurkeyGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of Pediatric Allergy-Immunology Institute of Health Sciences Marmara UniversityIstanbul 34865Türkiye Center for Stem Cell&gene Therapy Research and Practice University of Health Sciences TurkeyIstanbul 34255Türkiye Department of Child and Adolescent Psychiatry University of Health SciencesGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of Child and Adolescent Psychiatry Kocaeli University Faculty of MedicineKocaeli 41001Türkiye Center for Regenerative Medicine and Stem Cell Research&Manufacturing Liv HospitalIstanbul 34340Türkiye Department of Histology and Embryology Istinye UniversityFaculty of MedicineIstanbul 34010Türkiye Center for Stem Cell and Tissue Engineering Research and Practice Istinye UniversityIstanbul 34340Türkiye

BACKgROUND Autism spectrum disorder(ASD)is a complex neurodevelopmental disorder with multifaceted *** recent studies,neuroinflammation and immune dysregulation have come to the forefront in its *** are studies suggesting that stem cell therapy may be effective in the treatment of *** To evolve the landscape of ASD treatment,focusing on the potential benefits and safety of stem cell *** A detailed case report is presented,displaying the positive outcomes observed in a child who underwent intrathecal and intravenous Wharton’s jelly-derived mesenchymal stem cells(WJ-MSCs)transplantation combined with *** The study demonstrates a significant improvement in the child’s functional outcomes(Childhood Autism Rating Scale,Denver 2 Developmental Screening Test),especially in language and gross motor *** serious side effects were encountered during the 2-year *** The findings support the safety and effectiveness of WJ-MSC transplantation in managing ASD.

关键词： Autism spectrum disorder Neurorehabilitation Stem cell transplantation Wharton jelly mesenchymal stem cells Inflammation

DAMAgE ANALYSIS BY BOUNDARY ELEMENT METHOD

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Acta Mechanica Solida Sinica 1994年第3期7卷 245-255页

作者： z.z.Cen g.Swoboda f.Ito Tsinghua University BeijingChina Innsbruck University InnsbruckAustria

The response of cracked bodies subjected to loading was investigated by the boundary element method in this paper. The two-law elastic-cohesive-softening model was used for crack propagation analysis. The interface conditions for uncracked, craze, open crack, adhesive crack and slid crack parts were discussed and the corresponding incremental iteration algorithm was given. A simplified damage propagation model was presented. The technique has been applied to some specific examples which give the evidence that the method is satisfactory and efficient.

关键词： Algorithms Boundary element method Crack propagation Cracks Dynamic response Elasticity fracture mechanics Interfaces (materials) Iterative methods Loads (forces) Mathematical models

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Assessing reservoir connectivity with pressure/rate surveillance data

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Petroleum Science 2023年第2期20卷 1077-1086页

作者： g.f.J.Al-Khmaysawee z.Reza C.S.Kabir Missouri University of Sci.&Tech. RollaMOUSA University of Oklahoma NormanOKUSA Incendium Technologies Round RockTXUSA

Estimating reservoir connectivity is critical for assessing infill-drilling prospects and initiating fluid injection in enhanced oil recovery operations. Several methods have appeared in the literature over decades to meet these business needs, given that all tools, including seismic imaging, have limitations. Besides imaging, geochemical fingerprinting constitutes a powerful tool to gauge the compartmentalization question. However, real-time pressure/rate surveillance data allows assessing interwell connectivity vis-à-vis the overall drainage *** study presents a simplified approach to using the reciprocal-productivity index (RPI) vs. the total-material-balance time (tTMB) plot. This tool exhibits the same slope for those wells in the same compartment beyond the start of the boundary-dominated flow (BDf) period. The wells showing different slopes imply that they are in separate drainage volumes. The early-time transient period remains muted to minimize confusion on this Cartesian plot. We validated the proposed tool's efficacy with 2D and 3D models with increased degrees of reservoir complexity, followed by the verification phase with four field examples. The use of other analytical tools complemented our findings.

关键词： Reservoir compartmentalization Reciprocal-productivity index Total material-balance time Analysis of boundary-dominated flow period