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Étude et modélisation des perturbations produites au sein des microcontrôleurs STM32 soumis à des stress en impulsion / Study and modelling of the disturbances produced within the STM32 microcontrollers under pulsed stressesBacher, Yann 27 April 2017 (has links)
La fiabilité des microcontrôleurs est cruciale compte tenu de leur utilisation massive dans de nombreux domaines, surtout dans des environnements sévères. De ce fait, la robustesse aux perturbations électromagnétiques, en particulier à propos des alimentations, est un axe de développement majeur, que ce soit pour acquérir un avantage comparatif sur le marché, ou simplement pour assurer la sécurité des biens et des personnes. En ce sens, nous avons étudié le test de ces circuits soumis à des agressions transitoires rapides en salve définies par la norme IEC 61000-4-4. Les mécanismes spécifiques de propagation de la perturbation en mode commun sont mis en évidence, ainsi que leur conversion en mode différentiel. Plusieurs méthodes de mesure, dont certaines originales, ont été développées pour valider cette conversion, ainsi que les modes de propagation. Sur cette base, le réseau de distribution des alimentations a été particulièrement étudié et son influence sur la robustesse du circuit a été mise en évidence. Enfin, cette thèse ouvre de nouvelles perspectives d’amélioration de la robustesse des microcontrôleurs, pour ce type d’agression, et donc de leur fiabilité. / The reliability of the microcontrollers is crucial considering their massive use in numerous domains, especially in severe environments. Therefore, the robustness in the electromagnetic disturbances, in particular for the power supply network, is a major development, whether it is to acquire a comparative advantage on the market, or simply to assure the goods and people safety. Therefore, we studied the Fast Transient Burst test of integrated circuits, as defined by the IEC 61000-4-4 standard. The specific propagation mechanisms of the disturbance in common mode are highlighted, as well as their conversion in differential mode. Several measurements methods, among which certain novel, were developed to validate this conversion, as well as the propagation modes. Based on this, the power distribution network was particularly studied and its influence on the robustness of the circuit was highlighted. Finally, this work opens new perspectives of improvement of the microcontrollers’ robustness, for this kind of aggression, and thus their reliability.
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Teoretické predikce vlivu zašuměného kanálu na tlumočníkův výkon při simultánním tlumočení a jejich empirické ověření / Theoretical predictions of the impact of a noisy channel on interpreters' performance in simultaneous interpretation and their empirical verificationVolenová, Eva January 2017 (has links)
This thesis explores the issue of noise in the simultaneous interpreting process, using the concept of noise as defined in information theory and the model of communication developed by Claude Shannon. The theoretical section of this thesis first offers a brief explanation of the basic concepts involved in information theory, followed by a description of Shannon's model. Selected models of interpreting are then introduced based on this model of communication. A list of potential types of noise is then presented based on the literature examined that may have an impact on the interpreter during simultaneous interpreting. The empirical section of this thesis consists of a questionnaire and an experiment. The questionnaire determines to what extent interpreters find the potential types of noise from the list created in the theoretical section disruptive in their work. The list of types of noise is also expanded based on respondents' answers. The questionnaire also determines what strategies respondents employ to overcome adverse factors. The new types of noise and strategies employed are described in this thesis using open-ended answers from the respondents. The experiment tests the impact of a burst-noise channel on simultaneous interpreting. A total of 13 respondents took part in the experiment,...
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Exploring the dawn of the universe with the Sino-French SVOM mission / Explorer l'aube de l'univers avec la mission franco-chinoise SVOMCorre, David 30 November 2018 (has links)
Cette thèse s’inscrit dans le cadre de la préparation de la mission spatiale franco-chinoise SVOM (Space Variable Object Monitor) opérationnelle à l’horizon 2021 et qui aura pour but de détecter et caractériser les sursauts gamma. La première partie de la thèse consiste au développement d’un logiciel de simulation de COLIBRI (Catching OpticaL and Infrared BRight transIents), un télescope de suivi au sol de SVOM. Il comporte un simulateur de sursauts gamma, un exposure time calculator, un simulateur d'image, un algorithme estimant le redshift photométrique. Il a permis d'une part d’estimer les performances scientifiques du télescope afin de s'assurer qu'elles satisfont le cahier des charges, et d'autre part d'estimer une précision sur l'estimation de la distance du sursaut de l'ordre de 10% et 15% sur le redshift pour les sursauts à 3.5 < z < 8 et z > 8. La deuxième partie de la thèse porte sur l’étude de la propriété des poussières au sein des galaxies dans lesquelles se produisent ces sursauts gamma, mais aussi à l’étude de leur activité de formation stellaire. J'ai comparé les courbes d'extinction mesurées sur la ligne de visée de 7 GRBs à la courbe d'atténuation de leurs galaxies à l'aide d'un code de SED fitting, CIGALE. En comparant à un code de transfert radiatif on obtient des informations sur la distribution étoiles / poussière au sein de ces galaxies. Sur un échantillon élargi, on montre que les courbes d'atténuation pentues (plates) corrèlent avec des galaxies avec une faible (grande) atténuation due à la poussière, les moins (plus) activent en formation stellaire et les moins (plus) massives / This thesis lies within the framework of the sino-french SVOM (Space Variable Object Monitor) mission to be launched in 2021 whose objective is the detection and characterisation of Gamma-Ray Bursts (GRBs). The first part consists in the development of an end-to-end software for COLIBRI (Catching OpticaL and Infrared BRight transIents), a SVOM ground follow-up telescope. It consists in a GRB simulator, an Exposure Time Calculator, an image simulator and a photometric redshift algorithm. It allowed to estimate the telescope scientific performances to ensure that the optical design was fulfilling the scientific requirements. The relative accuracy on the photometric redshift delivered by COLIBRI is estimated to be about 10% and 15% for GRBs at 3.5 < z < 8 et z > 8. The second part of the thesis deals mainly with the study of dust properties in GRB host galaxies, but also with the star formation activity in these galaxies. We compare extinction curves measured along the GRB line of sight for 7 GRBs to the attenuation curve of their host galaxies measured with CIGALE, a SED fitting code. By comparing these curves to the results of a radiative transfer code, we obtain information about the geometrical distribution of dust and stars in these galaxies. On a larger sample of 23 galaxies, we show that the steepest (flattest) attenuation curves are associated to galaxies with a large (small) amount of dust attenuation, less (more) active in star formation and less (more) massive galaxies
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Connectivité fonctionnelle entre le noyau sensoriel principal du trijumeau et le noyau moteur du trijumeauSlaoui Hasnaoui, Mohammed 04 1900 (has links)
Les mouvements masticatoires sont générés par un réseau neuronal localisé dans le tronc cérébral connu sous le nom de générateur de patron central (GPC). De plus en plus d’évidences dans la littérature associent le noyau sensoriel principal du trijumeau (NVsnpr) au cœur rythmogène du GPC masticatoire, bien qu’il soit traditionnellement considéré comme un relais sensoriel au thalamus. La présente étude amène une nouvelle preuve de connectivité fonctionnelle entre le NVsnpr et le noyau moteur du trijumeau (NVmt) contenant les motoneurones (MNs) innervant les différents muscles masticatoires. Nos résultats indiquent que les neurones projetant vers NVmt sont situés dans le ¾ dorsal du NVsnpr. La stimulation électrique dans le NVsnpr dorsal évoque des réponses synaptiques excitatrices multiphasiques dans les MNs trigéminaux tandis que l'application locale de BAPTA, connue pour induire une activité rythmique dans les neurones du NVsnpr, évoqua aussi une activité rythmique dans les MNs, supportant davantage la relation fonctionnelle entre ces deux noyaux en termes de transmission de rythme. En imagerie calcique, la stimulation électrique de NVsnpr évoquait des réponses calciques dans les MNs situées principalement dans la région dorsolatérale contenant les MNs des muscles de fermeture et révéla un patron spécifique de connectivité entre les deux noyaux. L'organisation des projections semblait dépendre de manière critique de la localisation dorso-ventrale du site de stimulation au sein du NVsnpr. La principale tendance observée concernait la région DL de NVmt recevant des inputs du NVsnpr dorsal (R1 et R2), alors que la région ventromédiane de NVmt recevait plutôt des inputs de R2 et R3, qui représentent la majeure partie de la région intermédiaire du NVsnpr. Cette étude confirme et développe les expériences antérieures en explorant la nature physiologique et la topographie fonctionnelle de la connectivité entre NVsnpr et NVmt. / Masticatory movements are generated by a brainstem neuronal network known as the central pattern generator (CPG). Increasing evidence associate the trigeminal main sensory nucleus (NVsnpr) to the rhythmogenic heart of the masticatory CPG, despite the fact that it is conventionally seen as a sensory relay to the thalamus. The present study provides new evidence of a functional connectivity between NVsnpr and the trigeminal motor nucleus (NVmt), known to contain all the motoneurons (MNs) innervating jaw muscles. Our results indicate that neurons projecting to NVmt are located in the dorsal ¾ region of NVsnpr. Electrical stimulation of the dorsal NVsnpr induced multiphasic excitatory synaptic responses in trigeminal MNs while BAPTA application, which causes NVsnpr neurons to fire rhythmically, also induced rhythmic firing in some MNs, further emphasizing the functional relationship between these two nuclei in terms of rhythm transmission. In our calcium imaging experiments, electrical stimulation of NVsnpr evoked calcium responses in MNs located mainly in the jaw-closing region of NVmt and revealed a specific pattern of connectivity between the two nuclei. The organization of the projections seemed to depend critically on the dorsoventral location of the stimulation site within NVsnpr. The dorsolateral region of NVmt received mainly inputs from the dorsal NVsnpr (R1 and R2), whereas the ventromedial region of NVmt was found to receive inputs from R2 and R3 which account for the major part of the intermediate division of the NVsnpr. This study confirms and develops earlier experiments by exploring the physiological nature and functional topography of the connectivity between NVsnpr and NVmt that was demonstrated in the past with neuroanatomical techniques.
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Biochemické parametry energetického metabolismu v mozkomíšním moku u zánětlivých a nezánětlivých onemocnění CNS. / Biochemical parameters of energy metabolism in cerebrospinal fluid in inflammatory and non-inflammatory CNS diseases.Bořecká, Klára January 2020 (has links)
The basic examination of the cerebrospinal fluid provides a quick orientation in the diagnostic algorithm of CNS diseases about the nature of the pathological process. The current evaluation of cytology and biochemical parameters of glucose metabolism reports about the cells present and at the same time about the level of their activation. The aim of the work was to investigate the relationship between biochemical and cytological findings in cerebrospinal fluid in a large data set (n = 8 178), or confirm the hypothesis of a significant alteration in the Coefficient of Energy Balance (CEB) in cytological classes typically accompanying oxidative burst of phagocytes. CEB was subjected to analysis and comparison with other energy parameters (lacto-glucose ratio, gluco-lactate ratio, concentration of lactate and glucose in cerebrospinal fluid). The relationships between blood and cerebrospinal fluid glucose and lactate concentrations were investigated. CEB values were statistically significantly different in cytological groups, which reflected purulent inflammation, tumor involvement or infection by potential intracellular pathogens, the hypothesis was confirmed. Other energy parameters excluding glycorrhachia distinguish these cytological groups as well as CEB. There are inaccuracies in the derivation...
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Dynamic fMRI brain connectivity : A study of the brain’s large-scale network dynamicsBrantefors, Per January 2016 (has links)
Approximately 20% of the body’s energy consumption is ongoingly consumed by the brain, where the main part is due to the neural activity, which is only increased slightly when doing a demanding task. This ongoingly neural activity are studied with the so called resting-state fMRI, which mean that the neural activity in the brain is measured for participants with no specific task. These studies have been useful to understand the neural function and how the neural networks are constructed and cooperate. This have also been helpful in several clinical research, for example have differences been identified between bipolar disorder and major depressive disorder. Recent research has focused on temporal properties of the ongoing activity and it is well known that neural activity occurs in bursts. In this study, resting-state fMRI data and temporal graph theory is used to develop a point based method (PBM) to quantify these bursts at a nodal level. By doing this, the bursty pattern can be further investigated and the nodes showing the most bursty pattern (i.e hubs) can be identified. The method developed shows a robustness regarding several different aspects. In the method is two different variance threshold algorithms suggested. One local variance threshold (LVT) based on the individual variance of the edge time-series and one global variance threshold (GVT) based on the variance of all edges time-series, where the GVT shows the highest robustness. However, the choice of threshold needs to be adapted for the aims of the current study. Finally, this method ends up in a new measure to quantify this bursty pattern named bursty centrality. The derived temporal graph theoretical measure was correlated with traditional static graph properties used in resting state and showed a low but significant correlation. By applying this method on resting-state fMRI data for 32 young adults was it possible to identify regions of the brain that showed the most dynamic properties, these regions differed between the two thresholding algorithms
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Resource Allocation Schemes And Performance Evaluation Models For Wavelength Division Multiplexed Optical NetworksEl Houmaidi, Mounire 01 January 2005 (has links)
Wavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in network infrastructure and next-generation Internet architectures. WDM networks have the potential to provide unprecedented bandwidth, reduce processing cost, achieve protocol transparency, and enable efficient failure handling. This dissertation addresses the important issues of improving the performance and enhancing the reliability of WDM networks as well as modeling and evaluating the performance of these networks. Optical wavelength conversion is one of the emerging WDM enabling technologies that can significantly improve bandwidth utilization in optical networks. A new approach for the sparse placement of full wavelength converters based on the concept of the k-Dominating Set (k-DS) of a graph is presented. The k-DS approach is also extended to the case of limited conversion capability using three scalable and cost-effective switch designs: flexible node-sharing, strict node-sharing and static mapping. Compared to full search algorithms previously proposed in the literature, the K-DS approach has better blocking performance, has better time complexity and avoids the local minimum problem. The performance benefit of the K-DS approach is demonstrated by extensive simulation. Fiber delay line (FDL) is another emerging WDM technology that can be used to obtain limited optical buffering capability. A placement algorithm, k-WDS, for the sparse placement of FDLs at a set of selected nodes in Optical Burst Switching (OBS) networks is proposed. The algorithm can handle both uniform and non-uniform traffic patterns. Extensive performance tests have shown that k-WDS provides more efficient placement of optical fiber delay lines than the well-known approach of placing the resources at nodes with the highest experienced burst loss. Performance results that compare the benefit of using FDLs versus using optical wavelength converters (OWCs) are presented. A new algorithm, A-WDS, for the placement of an arbitrary numbers of FDLs and OWCs is introduced and is evaluated under different non-uniform traffic loads. This dissertation also introduces a new cost-effective optical switch design using FDL and a QoS-enhanced JET (just enough time) protocol suitable for optical burst switched WDM networks. The enhanced JET protocol allows classes of traffic to benefit from FDLs and OWCs while minimizing the end-to-end delay for high priority bursts. Performance evaluation models of WDM networks represent an important research area that has received increased attention. A new analytical model that captures link dependencies in all-optical WDM networks under uniform traffic is presented. The model enables the estimation of connection blocking probabilities more accurately than previously possible. The basic formula of the dependency between two links in this model reflects their degree of adjacency, the degree of connectivity of the nodes composing them and their carried traffic. The usefulness of the model is illustrated by applying it to the sparse wavelength converters placement problem in WDM networks. A lightpath containing converters is divided into smaller sub-paths such that each sub-path is a wavelength continuous path and the nodes shared between these sub-paths are full wavelength conversion capable. The blocking probability of the entire path is obtained by computing the blocking probabilities of the individual sub-paths. The analytical-based sparse placement algorithm is validated by comparing it with its simulation-based counterpart using a number of network topologies. Rapid recovery from failure and high levels of reliability are extremely important in WDM networks. A new Fault Tolerant Path Protection scheme, FTPP, for WDM mesh networks based on the alarming state of network nodes and links is introduced. The results of extensive simulation tests show that FTPP outperforms known path protection schemes in terms of loss of service ratio and network throughput. The simulation tests used a wide range of values for the load intensity, the failure arrival rate and the failure holding time. The FTPP scheme is next extended to the differentiated services model and its connection blocking performance is evaluated. Finally, a QoS-enhanced FTPP (QEFTPP) routing and path protection scheme in WDM networks is presented. QEFTPP uses preemption to minimize the connection blocking percentage for high priority traffic. Extensive simulation results have shown that QEFTPP achieves a clear QoS differentiation among the traffic classes and provides a good overall network performance.
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Electromagnetic signals of neutron star mergers and multimessenger astrophysicsHao Wang (18387573) 16 April 2024 (has links)
<p dir="ltr">Neutron star mergers generate powerful gravitational waves and various types of electromagnetic signals, including gamma-ray bursts (GRB), kilonovae, and their afterglows. Observing and modeling these signals help us understand the physical processes of the merger events. Radiation from mergers can also serve as probes to study nuclear physics and cosmology. In this report, I focus on two types of signals: the GRB afterglow and the kilonova. GRB afterglows are non-thermal radiation produced by the interaction of relativistic jets and circumburst material, where the jets are launched perpendicular to the merger plane. Kilonovae are the thermal radiation emitted from the hot materials ejected during the merger. Besides the modeling of these objects, I also investigate their application in multimessenger astrophysics, especially the constraint on the expansion rate of the Universe. </p><p dir="ltr">First, I developed a GRB afterglow model to account for the off-axis observation of a structured jet. Using a jet structure derived from a three-dimensional general relativistic magnetohydrodynamic simulation, we performed a joint analysis of the multimessenger data of the neutron star merger event GW170817, including the gravitational wave data and GRB afterglow data in the radio band. We have tightly constrained the observing angle of GW170817 and broken the degeneracy between the inclination angle and luminosity distance measured in gravitational waves. With a better constrained distance, we improved the standard siren measurement of the Hubble constant to $H_0 = 69.5\pm 4\ \mathrm{km\ s^{-1}\ Mpc^{-1}}$. The error bar has been reduced by a factor of 2. This work demonstrates that the modeling of off-axis GRB afterglow can significantly improve the standard siren method, provided that we have a reliable jet structure.</p><p dir="ltr">Second, I upgrade the GRB afterglow model in the first work, extending it to the late time where lateral spreading of the GRB jet becomes important. In this model, the ultra-relativistic blastwave is approximated by an infinitely thin two-dimensional surface. With this approximation, the hydrodynamic equations can be analytically integrated over the radius. Further assuming axial symmetry, the three-dimensional hydrodynamic simulation can be reduced to one dimension, which significantly increases the computational efficiency. We have compared our method to full numerical simulations and existing GRB afterglow modeling tools. The comparison shows good agreement and verifies our approach. Compared to these tools, our model has better flexibility and is applicable in a broader context. This method has been developed into a numerical code, \texttt{jetsimpy}, which we have provided to the community. It will serve as a powerful tool in the era of multimessenger astrophysics.</p><p dir="ltr">Finally, I investigate the possibility of long-lived massive neutron stars as neutron star merger remnants. A long-lived massive neutron star can inject a significant amount of energy into the merger ejecta, boosting the luminosity of kilonova by several orders of magnitude. However, this type of event has not yet been observed in optical sky surveys. We developed a boosted kilonova model with a detailed calculation of the photoionization process to better describe the efficiency of energy injection from spin down power to the ejecta. Our study found that boosted kilonovae, if commonly occurring, they should have already been observed given the accumulated time in sky surveys. As a result, the absence of detection implies that long-lived massive neutron stars as neutron star merger remnants are likely to be rare in the Universe.</p>
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Developing a Rainfall-Runoff Routing Model using Spatially Distributed Travel Times : Modelling a Cloudburst Event in an Urban Catchment / Utveckling av en avrinningsmodell tillämpande spatialt fördelade rinntider : Modellering av ett skyfall i urban miljöEkeroth, Sara January 2022 (has links)
The future holds challenges for urban areas when it comes to handling pluvial floodings, occurring when the rainfall intensity exceeds both the man-made and natural infiltration and drainage capacity. To gain understanding of the effects and needed measures, tools for modelling the urban response to events such as cloudbursts are needed. The aim of this project was to build a model using the Spatially Distributed Travel Time (SDTT) approach to model the rainfall-runoff response of an urban watershed. The model was developed in ArcGIS Pro using a built-in module ArcPy allowing for the use of a Python script to ensure fast calculations and simulations on grid cell basis. In total six smaller watersheds within the larger catchment were modelled with a variety in size and degree of urbanisation. Unlike fully distributed models solving for both the continuity equation and momentum equation, the models save time by applying kinematic wave approximation solving the steady state, uniform continuity equation and the Manning’s equation. The study uses only one calibration parameter representing the upstream area contributing to runoff, used for adjusting the travel times to ensure they are not too slow which could generate a delay and underestimation of the peak discharge. The model was parameterized for a cloudburst event that occurred in the city of Gävle, in the year of 2021, and was validated against a fully distributed model (MIKE 21) simulating the same event. The generated response from the SDTT model successfully returns similar hydrographs to that of a fully distributed model in most cases. It performed very well in high urbanised areas with an even spatial distribution of the two land cover classes used, impervious and pervious surfaces, and small volumes of depressions. In areas with lesser degree of urbanisation and larger depression volumes collecting runoff, the simplified model struggled to capture the draining dynamics of these. However, the model managed to match the time to peak reasonably well in the struggling areas as well. To increase the applicability of the model the upstream area contributing to runoff should be based on physical characteristics and not calibration. Further, the model should be applied to other areas preferably using other rainfall event data or design storms, as well as investigate the performance using more than two land cover classes. Finally, a sensitivity analysis could be performed for parameters that were now set to fixed values, done so to reduce the calibration. / Framtiden kommer bjuda på utmaningar för urbana områden när det kommer till hanteringen av pluviala översvämningar, vilka inträffar när nederbördsintensiteten överstiger både den konstgjorda och naturliga infiltrations- och dräneringskapaciteten. För att få ökad förståelse av effekterna samt besluta om nödvändiga åtgärder behövs nya verktyg för att modellera den urbana responsen till följd av extrem nederbörd så som skyfall. Syftet med detta projekt vara att med hjälp av spatialt fördelade rinntider och kinematiska vågmodellen modellera nederbörden och avrinningen i ett urbant avrinningsområde. Modellen utvecklades i ArcGIS Pro med hjälp av den inbyggda modulen ArcPy vilken tillåter användningen av ett Python-skript som ger snabba beräkningar och korta simuleringar applicerade på cellnivå. Totalt modellerades sex mindre avrinningsområden inom det större området, alla med olika storlek och urbaniseringsgrad. Till skillnad från fullt distribuerade modeller som löser både kontinuitetsekvationen och rörelsemängdsekvationen, sparar modellen tid genom att tillämpa kinematisk vågteori, stationära kontinuitetsekvationen samt Mannings ekvation. Studien använder endast en kalibreringsparameter vilken representerar området uppströms om varje cell som bidrar till avrinning nedströms. Denna används för att justera rinntiderna för att säkerställa att modellen inte returnerar för långsamma tider vilket kan generera en fördröjning av responsen och underskattning av maxflödet. Modellen parametriserades för ett skyfall som inträffade i Gävle år 2021, och validerades mot en fullt distribuerad modell (MIKE 21) som simulerade samma händelse. Den modellerade responsen från avrinningsmodellen byggd på spatialt fördelade rinntider kunde framgångsrikt leverera liknande hydrografer som den fullt distribuerade modellen. Modellen presterade framför allt bra i områden med hög urbaniseringsgrad innehavande en jämn spatial fördelning av de två marktäckningsklasserna som användes, nämligen hårdgjorda och icke hårdgjorda ytor, samt små volymer av sänkor i området. I områden med en lägre urbaniseringsgrad och större volymer sänkor vilka fördröjer avrinningen hade modellen svårare att producera liknande hydrografer troligen då den förenklade modellen ej kan fånga dynamiken av att fylla och tömma dessa sänkor. Däremot lyckades den fortfarande att matcha tiden för maxflödet även för dessa områden. För att öka modellens tillämpbarhet bör området uppströms som bidrar till avrinning nedströms baseras på fysikaliska egenskaper och inte kalibrering. Vidare bör modellen tillämpas på andra områden, helst med hjälp av andra nederbördsdata eller designregn, samt undersöka prestandan om mer än två marktäckningsklasser används. Slutligen kan en känslighetsanalys utföras för parametrar som nu satts till fasta värden, detta för att minska kalibreringen.
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Investigation of LTP-like Plasticity, Memory and Prefrontal Cortical Thickness: a TMS-EEG and Brain Imaging StudyDrodge, Jessica 04 January 2023 (has links)
Introduction: Memory is a complex cognitive process formerly linked to mechanisms of brain plasticity that can be estimated in the left dorsolateral prefrontal cortex (DLPFC) using transcranial magnetic stimulation and electroencephalography (TMS-EEG). Also, cortical thickness in the DLPFC may be a potential proxy measure of brain plasticity as previous literature reports a link between better memory and thicker cortex. However, the link between brain plasticity and memory performance as well as DLPFC thickness remains to be clarified. Methods: Intermittent theta burst stimulation (iTBS) probed plasticity-like mechanisms in the left DLPFC in 17 cognitively healthy participants. TMS-EEG recordings were performed before and after sham and active iTBS to quantify plasticity via transcranial magnetic stimulation-evoked potentials (TEPs). Composite memory scores for each domain (verbal episodic, visual episodic and working memory) were obtained using the Cambridge Neuropsychological Test Automated Battery. Anatomical T1 images were acquired by magnetic resonance imaging and processed by open-source software (CIVET) and the Automated Anatomical Labeling atlas to extract cortical thickness of the DLPFC. All statistical analyses (linear mixed model, Tukey's post hoc test and Pearson's correlations) were completed in R Studio. Results: iTBS resulted in increased TEP amplitude P30 (F= 5.239, p = 0.029), as shown by a significant interaction between condition (iTBS, sham) and time (pre- and post-condition). Specifically, Tukey's post hoc test revealed that the P30 increase was near trending significant post-iTBS compared to pre-iTBS for the active condition (p = 0.166) but not for the sham condition (p = 0.294). A trending significant relationship was observed between the magnitude of P30 change post-iTBS and thicker left DLPFC (r = 0.488; p = 0.108). Lastly, no significant relationships between P30 change and memory performance were observed. Conclusion: These preliminary findings suggest there could be a relationship between increased capacity for brain plasticity and a thicker left DLPFC. To further investigate these relationships, we plan to recruit additional cognitively healthy participants. Our preliminary findings support the foundation for future clinical studies in which DLPFC thickness could be explored as a predictive factor for response to plasticity-targeting iTBS treatment.
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