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Diagnostic neuroradiology:Ready for the neurointerventional age?

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World Journal of Radiology 2012年第9期4卷 401-404页

作者： karl-olof lvblad Vitor Mendes Pereira Service Neuro-diagnostique et Neuro-interventionnel Geneva University Hospitals

Acute cerebral ischemia or stroke is currently considered an emergency for which therapeutic options are available if the therapeutic window of 4.5 h is *** modalities have progressed greatly over the last few decades,rendering ischemia detectable in the first hours after the ***,in order for treatment to be efficacious it is necessary to speed up all the processes before the start of ***,one must decrease the time to arrival at the hospital and to the radiological method that is to be employed(be it computed tomography or magnetic resonance imaging);only then will the medical or interventional techniques available fulfill their potential.

关键词： Stroke Interventional neuroradiology Thrombolysis Magnetic resonance imaging Computed tomography

Diagnostic neuroradiology for the interventional neuroradiologist

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World Journal of Radiology 2013年第11期5卷 386-397页

作者： Vitor Mendes Pereira Maria Isabel Vargas Ana Marcos Philippe Bijlenga Ana Paula Narata Sven Haller karl-olof lvblad Service Neuro-diagnostique et Neuro-interventionnel Geneva University Hospitals Service de Neurochirurgie HUG Geneva University Hospitals

In order to further improve the impact of the continuously evolving neurointerventional techniques, the interventional neuroradiologist needs to have at his disposal more powerful techniques to image the central nervous system. With the recent development of diagnostics techniques that are computed tomography and magnetic resonance based we are now able to assess not just morphology, but also physiology, physiopathology and function. This review discusses the place of diagnostic techniques in the evaluation that the interventional neuroradiologist hast to make when confronted with patients. We provide an overview of current techniques for the brain and spine.

关键词： Neuroradiology Brain Imaging Magnetic resonance Interventional radiology

Microglia:a promising therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thomas Skutella karl Kiening Andreas Unterberg Alexander Younsi Department of Neurosurgery Heidelberg University HospitalHeidelbergGermany Department of Neuroanatomy Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

Microglia are present throughout the central nervous system and are vital in neural repair,nutrition,phagocytosis,immunological regulation,and maintaining neuronal *** a healthy spinal cord,microglia are accountable for immune surveillance,however,when a spinal cord injury occurs,the microenvironment drastically changes,leading to glial scars and failed axonal *** this context,microglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynamic and multifaceted injury response is mediated by microglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem/progenitor *** a clear understanding of their essential nature and origin,the mechanisms of action and new functions of microglia in spinal cord injury require extensive *** review summarizes current studies on microglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes microglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery immune regulation M1/M2 activation macrophages microglia neuroinflammation spinal cord injury therapy

Mathematical Models and Numerical Methods for High Frequency Waves

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Communications in Computational Physics 2007年第5期2卷 827-880页

作者： olof Runborg Department of Numerical Analysis School of Computer Science and CommunicationKTH10044 StockholmSweden.

The numerical approximation of high frequency wave propagation is important in many *** include the simulation of seismic,acoustic,optical waves and *** the frequency of the waves is high,this is a difficult multiscale *** wavelength is short compared to the overall size of the computational domain and direct simulation using the standard wave equations is very ***,there are computationally much less costly models,that are good approximations of many wave equations precisely for very high *** for linear wave equations these models are often *** goal of this paper is to review such mathematical models for high frequency waves,and to survey numerical methods used in *** focus on the geometrical optics approximation which describes the infinite frequency limit of wave *** will also discuss finite frequency corrections and some other models.

关键词： Geometrical optics wave equation Helmholtz equation high frequency waves eikonal equation ray tracing multiscale problems.

Beginning from the end:the presynaptic terminal as a pathomechanism hub in frontotemporal dementia and amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3217-3218页

作者： laura Huggon Emma l.Clayton UK Dementia Research Institute at King’s College london LondonUK Department of Basic and Clinical Neuroscience Institute of Psychiatry Psychology&NeuroscienceKing’s College LondonLondonUK

Frontotemporal dementia and amyotrophic lateral sclerosis:Frontotemporal dementia(F T D)and amyo t rophic lateral sclerosis(AlS)are neurodegenerative diseases with significant overlapping *** these neurodegenerative diseases affect different neuronal populations(with FTD affecting neurons of the frontal and temporal lobes,and AlS affecting upper and lower motor neurons),these two diseases are complexly *** and AlS exist on a disease spectrum,with shared genetic causes,clinical presentations,and pathologies.

关键词： diseases amyotrophic sclerosis

Deformation,fragmentation and acceleration of a controlled fragmentation charge casing

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Defence Technology（防务技术） 2019年第5期15卷 786-795页

作者： Andreas Helte olof Andersson Patrik lundberg FOI Defence and SecuritySystems and Technology

Two different finite element software,lS-DYNA and Impetus,have been evaluated to test their ability to predict the deformation,fragmentation and acceleration of a controlled fragmentation charge *** general-purpose program lS-DYNA was used with a multi-material AlE formulation and a masspreserving erosion criterion coupled to a Johnson-Cook fracture *** the Impetus simulations,a third order lagrangian element formulation was used for the casing and a node-splitting element erosion treatment coupled to a Cockcroft-latham failure criterion was used to describe casing *** high-explosive gases were described by a discrete particle *** order to acquire data to validate our computational tools and constitutive models,a series of experiments have been performed using a laboratory charge with an internal grooved *** the test series,the charge geometry was fixed except that the groove depth were varied from very shallow to very deep resulting in different deformation patterns,fracture modes and terminal *** diagnostic tools captured the different stages of the expansion and fragmentation of the casing.A high-speed framing camera depicted the deformation pattern before fragmentation and was used to determine the moment when the casing *** different complementary techniques were used to follow the acceleration of the fragments;a Photon Doppler velocimetry to determine the initial acceleration of the casing,double exposed radiographs to estimate the fragment velocity after break-up and a high-speed video to determine the terminal velocity of the fragment after leaving the *** addition,the fragments were soft recovered in a set of sawdust pit tests and their final shape and weight were measured.A SEM was used to characterise the fracture surfaces and to determine the modus of fracture(tensile or shear failure).Comparisons to experiments show that both software can predict the change in deformation behaviour

关键词： Controlled fragmentation Fracture mechanics lS-DYNA Impetus

Why People live in Flood-Prone Areas in Akuressa, Sri lanka

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International Journal of Disaster Risk Science 2018年第2期9卷 143-156页

作者： Johan Askman olof Nilsson Per Becker Division of Risk Management and Societal Safety Lund University

To investigate why people live in areas at high risk of floods, a qualitative case study was carried out in the areas around Akuressa, in southwest Sri lanka. Data collection consisted mainly of semistructured interviews with local residents and government officials. The purpose was to study why people live in areas at high risk of floods, by looking beyond the purely physical aspects of living with hazards and exploring the underlying social factors. Four main factors were identified: an overall good living situation; a sense of place; difficulties relocating; and being well-adapted to the situation. The analysis also examined whether government officials shared the views of local residents. The findings highlighted both areas of consensus and discrepancies related to risk awareness, and the efficiency of risk reduction measures that had been implemented by the government. The case study identified and explored underlying social factors, such as risk normalization, risk trade-offs, and push-and-pull processes, which seem to influence the decision to live in a high-risk area.

关键词： Flood risk Risk awareness Risk perception Sri lanka

Influence of confining prestress on the transition from interface defeat topenetration in ceramic targets

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Defence Technology（防务技术） 2016年第3期12卷 263-271页

作者： Patrik lUNDBERG RenéRENSTROM olof ANDERSSON FOI Swedish Defence Research AgencySE-164 90 StockholmSweden

Replica scaled impact experiments with unconfined ceramic targets have shown that the transition velocity,i.e.,the impact velocity at which interface defeat ceases and ceramic penetration occurs,decreased as the length scale increased.A possible explanation of how this scale effect is related to the formation of a cone crack in the ceramic has been presented by the authors in an earlier ***,the influence of confinement and prestress on cone cracking and transition velocity is *** hypothesis is that prestress will suppress the formation and growth of the cone crack by lowering the driving stress.A set of impact experiments has been performed in which the transition velocity for four different levels of prestress has been *** transition velocities as a function of the level of confining prestress is compared to an analytical model for the influence of prestress on the formation and extension of the cone crack in the ceramic *** experiments and model indicate that prestress has a strong influence on the transition from interface defeat to penetration,although the model underestimates the influence of prestress.

关键词： Impact Ceramic Armour Interface defeat Dwell Confinement Prestress

AN ADAPTIVE FAST INTERFACE TRACKING METHOD

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Journal of Computational Mathematics 2015年第6期33卷 576-586页

作者： Yana Di Jelena Popovic olof Runborg lSEC NCMIS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China Department of Numerical Analysis CSC KTH 100 44 Stockholm Sweden Department of Mathematics and Swedish e-Science Research Center (SeRC) KTH 100 44 Stockholm Sweden

An adaptive numerical scheme is developed for the propagation of an interface in a velocity field based on the fast interface tracking method proposed in [2]. A multiresolution stategy to represent the interface instead of point values, allows local grid refinement while controlling the approximation error on the interface. For time integration, we use an explicit Runge-Kutta scheme of second-order with a multiseale time step, which takes longer time steps for finer spatial scales. The implementation of the algorithm uses a dynamic tree data structure to represent data in the computer memory. We briefly review first the main algorithm, describe the essential data structures, highlight the adaptive scheme, and illustrate the computational efficiency by some numerical examples.

关键词： Interface tracking Multiresolution adaptivity Fast algorithms.