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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

mTOR Regulation of Hippocampal Granule Cell Pathology in Temporal Lobe Epilepsy

Hester, Michael S. January 2014 (has links)
No description available.
72

Public School Law: Student Search and Seizure in K-12 Public Schools

Bedden, Dana T. 21 March 2006 (has links)
School officials are constantly challenged to perform a myriad of duties in an extremely complex and demanding job with numerous responsibilities. They are expected to work with a variety of students, faculty and parents under difficult circumstances. "Faced with multiple needs, with the necessity of making fast decisions in an atmosphere of fragmented time, administrators are liable for everything they do." School administrators need to understand the rights guaranteed to students by the Fourth Amendment and how it applies to the school setting. This document will provide an overview of student search and seizure in kindergarten to 12th grade (K-12) public schools in a non-traditional dissertation (non-experimental design) format by providing an historical review of the relevant case law. Specifically, based upon legal research, it will review relevant Supreme Court cases, post-New Jersey v. T.L.O. federal, Pennsylvania and other state court cases related to search and seizure in K-12 public schools. The conclusion and summary will provide answers to the guiding questions, provide a conceptual model, outline what is a reasonable search, and provide a short practical school law exercise to test the reader's understanding of search and seizure in public schools. / Ed. D.
73

The gut-brain axis in seizure susceptibility: A role for microbial metabolite S-equol

Bouslog, Allison Faye 26 May 2021 (has links)
Epilepsy is a complex, chronic neurological disorder with diverse underlying etiologies characterized by the spontaneous occurrence of seizures. Epilepsy affects all ages from neonates to elderly adults, with the most recent CDC estimates stating that ~3 million adults and over 400,000 children are currently suffering from active epilepsy in the U.S. alone. In adults, the leading cause of epilepsy worldwide in central nervous system (CNS) infection, while in neonates the most common cause of seizures is hypoxic/ischemic encephalopathy (HIE). However, in both adults and neonates, current antiepileptic drugs (AEDs) are ineffective in 30-50% of patients, despite the availability of over 20 FDA approved AEDs with diverse molecular targets. This disparity highlights a critical need for novel therapeutics in seizure-susceptibility and epilepsy. The microbes that inhabit gut mucosal surfaces, termed the gut microbiota, have been increasingly implicated in the pathology of neurological diseases including epilepsy. This gut-brain axis is an intriguing therapeutic target in epilepsy as gut microbes can affect the CNS through multiple mechanisms including vagus nerve signaling, immune-gut interactions, and through production of microbial-metabolites including neurotransmitters, short chain fatty acids (SCFAs), lactate, vitamins, and S-equol. Furthermore, the gut microbiota is crucial for neurodevelopment, indicating that the gut-brain axis may be involved in pediatric seizure-susceptibility. This dissertation reviews current evidence on the role of gut metabolites in seizure-susceptibility in epilepsy, highlighting the microbial-derived metabolite S-equol as a potential novel AED. We then evaluate gut microbiome alterations in the Theiler's murine encephalomyelitis virus (TMEV) adult mouse model of CNS infection-induced seizures and find decreases in S-equol-producing bacteria in the gut microbiomes of TMEV-infected mice with seizure phenotypes. We characterize the effect of exogenous S-equol on neuronal function in vitro, demonstrating a reduction in neuronal excitation following S-equol exposure. We additionally characterize entorhinal cortex (ECTX) pyramidal neuronal hyperexcitability, and demonstrate the ability of exogenous S-equol to ameliorate CNS-infection-induced ECTX neuronal hyperexcitability ex vivo. Finally, we demonstrate that perinatal and postnatal exposure to antibiotics alters the gut microbiome and increases seizure-susceptibility following HIE exposure in p9/p10 mice, potentially via sex-specific alterations in neuronal function. Together, this dissertation evaluates the gut-brain axis in pediatric and adult mouse models of seizure-susceptibility and identifies the gut metabolite S-equol as a potential target for the treatment of seizures. / Doctor of Philosophy / Epilepsy, a disease defined by the occurrence of two or more spontaneous seizures, affects over 50 million people worldwide. This makes epilepsy one of the most common chronic neurological disorders across the globe. People with epilepsy suffer increased mortality, lower quality of life, and increased social stigma. There is currently a crisis in the treatment and management of epilepsy, because although over 20 different anti-epileptic drugs (AEDs) are available to patients, these drugs only work in ~70% of individuals with epilepsy, leaving 30% of patients with uncontrolled seizures. Currently available AEDs are designed to target classical central nervous system (CNS) components. However, a growing body of evidence suggests that epilepsy is related to complex systems throughout the body. Therefore, in this manuscript we explore novel therapeutic targets outside of the CNS for the management of seizures. Over 1000 species of bacteria live in the in the human gut, and are termed the gut microbiota. Gut microbes produce a variety of chemicals that circulate through the body and can even reach the brain. Interaction of chemicals produced by the gut microbiota and brain chemistry have been shown to affect disease outcomes in Autism Spectrum Disorder, Parkinson Disease, and other brain disorders. However, very few studies have examined the possibility of a role for the gut microbiota in epilepsy. In this dissertation, we review chemicals produced by the gut microbiota that may alter epilepsy biology. We additionally examine gut microbiota alterations in a rodent model of epilepsy, and identify a novel chemical, S-equol, that is produced by the gut microbiota and impacts epilepsy biology in our rodent model. Lastly, we explore how altering the maternal gut microbiota in rodents can influence seizure-susceptibility in infants.
74

Students' First and Fourth Amendment Rights in the Digital Age: An Analysis of Case Law

Nowak, Benjamin Adam 27 April 2014 (has links)
In January, 2012, the Supreme Court of the United States refused to hear three cases involving student online speech, or cyberspeech. This indicates that the Court is content with lower courts applying First Amendment jurisprudence developed over 40 years ago to a rapidly advancing digital environment where students carry the equivalent of personal computers in their pockets, have an ever-growing telepresence, and rely on cyberspeech as their primary means of communicating with the world around them. Lower courts also are beginning to grapple with challenges to students Fourth Amendment right to be free from unreasonable search and seizure as it relates to the digital environment described above. Recently, lower courts in Mississippi, Texas, Minnesota, and Kentucky have applied standards set forth decades ago to decide cases involving searches of students mobile devices and Web 2.0 applications. Given the absence of guidance from the Supreme Court, this study aims to: (1) identify and analyze trends in the current application of legal standards related to student cyberspeech and search and seizure in the digital age; (2) synthesize these findings into a set of essential guidelines for school officials to use as they navigate a legal landscape that has yet to be well defined; and (3) make recommendations to further develop the body of law. Findings indicate that school officials have the legal authority to restrict off-campus student cyberspeech when certain conditions are met, and Tinker governs cases in this area. Seriously threatening, slanderous, or obscene cyberspeech is not constitutionally protected and can be restricted prior to an actual disruption. Off-campus student cyberspeech that reaches the school can legally be restricted so long as evidence shows that it caused a material and substantial disruption. In addition, students possess reasonable expectations of privacy in their personal mobile devices and password-protected private Web 2.0 communications. T.L.O governs searches of students personal mobile devices and Vernonia appears to govern cases involving searches of students Web 2.0 applications. Substantive suspicion at the outset, carefully tailored searches, and a clear governmental interest will keep school officials from violating students Fourth Amendment protections. / Ed. D.
75

Crises fébriles et syndrome d'épilepsie mésio-temporale. Une modélisation chez la souris de la théorie du double choc / Febrile seizures and Mesial-Temporal Lobe Epilepsy syndrome : A modelisation of the "two-hits theory" in mice

Hamelin, Sophie 23 April 2012 (has links)
Les crises fébriles représentent l'évènement épileptique le plus fréquent dans l'espèce humaine et touchent 5 % de la population. Bien que la bénignité de leur pronostic ait été établie par de nombreuses études prospectives, une infime proportion de ces enfants va développer un syndrome d'épilepsie mésio-temporale avec sclérose de l'hippocampe. L'hypothèse de ce travail est que la crise fébrile serait nécessaire mais non suffisante au développement de ce type d'épilepsie, un second élément au potentiel épileptogène serait ainsi indispensable. Notre travail a montré que les crises hyperthermiques chez la souris constituent une bonne approche pour modéliser les crises fébriles de l'enfant. Nous avons ainsi montré que les conséquences des crises hyperthermiques étaient différentes selon la séquence de survenue par rapport au second évènement épileptogène. (i) Lorsque la crise hyperthermique précède l'injection de kaïnate dans l'hippocampe, elle accélère la phase d'épileptogenèse et majore la dispersion des cellules granulaires du gyrus denté, sans modifier la perte cellulaire des neurones pyramidaux de la corne d'Ammon. Elle entraine également une modification du pattern des décharges rythmiques hippocampiques lors de la phase chronique, sans modifier la fréquence ni la durée de ces décharges. (ii) Lorsque la crise hyperthermique succède à la présence d'une dysplasie de la partie CA3 de la corne d'Ammon d'origine génétique, elle semble diminuer le risque de crise chez les animaux KO pour le gène de la double cortine. Pourtant, l'augmentation de la fréquence d'une néo-expression du NPY par les cellules granulaires, chez les animaux Hz pour cette mutation, suggère que les crises hyperthermiques favoriseraient la route vers une épilepsie, tout en activant la mise en place de mécanismes protecteurs contre la survenue des crises. En conclusion, les crises hyperthermiques faciliteraient la route vers l'épilepsie, mais n'auraient pas d'effet facilitateur sur la route vers la crise. / Whereas febrile seizures are the most common seizure type in children and are reported in the history of mesial temporal lobe epilepsy, their role in its etiology remains controversial. They have been suggested to modify the functional organization of the hippocampus but to require another insult to induce epilepsy. To test this hypothesis, we developed a model of hyperthermic seizures in mice and examined their long-term consequences on a second insult induced either by (i) intra-hippocampal kaïnic acid injection in adult animals or by (ii) hippocampal dysplasia developed by double-cortin knock-out mice. (i) While adults, mice that were subjected to hyperthermic seizures developed epileptogenesis more rapidly than sham mice. The occurrence and duration of hippocampal paroxysmal discharges were not modified by hyperthermic seizures, as was their mean time-frequency. In this model, hyperthermic seizures increased the granular cells dispersion, but have no influence on the massif pyramidal cell loss. (ii) In preexisting hippocampal dysplasia, the occurrence of hyperthermic seizures did not increase the proportion of seizures in double-cortin knock-out mice after hyperthermic seizures, and suggest that hyperthermic seizures rather might decrease recurrent seizures via the neo-expression of NPY. In conclusion, hyperthermic seizures in immature mice might facilitate the route to epilepsy, but did not exacerbate the route to seizures.
76

Localisation et caractérisation du déroulement de la crise d'épilepsie temporale / Localization and characterization of the seizure development of temporal lobe epilepsy

Vélez-Pérez, Hugo Abraham 21 October 2010 (has links)
L’électroencéphalogramme (EEG) est un examen incontournable pour le diagnostic, la définition des structures cérébrales responsables de l’origine de crises et la classification des épilepsies. Cependant les enregistrements recueillis à la surface du scalp sont très perturbés par des artefacts et du bruit, ce qui complique considérablement l’interprétation clinique ou l’analyse automatique.Ce travail a pour objectif d’extraire des descripteurs des signaux d’EEG de surface qui peuvent conduire à la caractérisation de la dynamique spatio-temporelle des crises partielles du lobe temporal. Les estimateurs de relations inter-voies appliqués sont les méthodes linéaires paramétriques symétriques et non symétriques telles que l’inter-spectre (S), la cohérence (C), la Directed Transfert Function (DTF) ou la Partial Directed Coherence (PDC). Les relations sont estimées sur des EEG réels contenant une crise. La détection de fortes relations inter-voies est exploitée pour latéraliser puis caractériser la crise. Toutes les méthodes sont appliquées sur des signaux EEG bruts et prétraités. Une étape de prétraitement basée sur la séparation et classification de sources et le débruitage est mise en œuvre afin d’éliminer les artefacts et le bruit avec une perte minimale d’information en diminuant le risque de fausses détections de relations de connectivité inter-signaux. Les résultats obtenus sur 51 crises montrent que le prétraitement améliore la détection et le taux de bonnes latéralisations. Une méthode de couplage entre l’IS et les méthodes paramétriques directives (PDC et DTF) permet d’améliorer la caractérisation des crises / The electroencephalogram (EEG) is the essential clinical examination for the diagnosis, the definition of brain structures responsible of seizures and epilepsy classification. However, the signals collected on the surface of the scalp are very disturbed by artifacts and noise, which complicates the clinical interpretation or the automatic analysis. This work aims to extract descriptors of surface EEG signals that can lead to the spatio-temporal characterization of the temporal lobe seizures. The inter-channel relationship estimators applied are parametric linear methods, such as cross-spectrum (S), coherence (C), Directed Transfer Function (DTF) or Partial Directed Coherence (PDC). Relations are estimated on real EEG recordings containing a crisis. The detection of strong inter-channel relationships is exploited in order to lateralize and to characterize seizures. All methods are applied to raw and preprocessed EEG signals. A preprocessing step, based on the separation and classification of sources and denoising is implemented to remove artifacts and noise with a minimal loss of information by reducing the risk of false detections of inter-signal connectivity relationships. The results on 51 crises show that a signal preprocessing improves the detection and the rate of correct lateralization. A coupling method between S and directivity parametric methods (PDC and DTF) improves the characterization of crises
77

Effectivité des droits des créanciers et protection du patrimoine familial / The effectiveness of the rights of the creditors and the protection of family

Tissot, Stéphanie 12 December 2015 (has links)
Le droit de l’exécution forcée offre aux créanciers des voies de droit pour contraindre les débiteurs défaillants à exécuter leurs obligations à leur égard. Ce rapport d’obligation est cependant moins un lien entre deux personnes qu’un rapport entre deux patrimoines. C’est ce qui explique que les obligations s’exécutent sur les biens des débiteurs. La matière devrait donc être hermétique à la situation familiale du débiteur et ne s’intéresser qu’au patrimoine personnel de celui-ci. Cependant, malgré l’absence de personnalité juridique de la famille, il est communément question du « patrimoine familial ». Entendu au sens large, le « patrimoine familial » intéresse alors nécessairement les tiers créanciers. Certains biens en effet, font l’objet d’une protection particulière, destinée, plus largement, à protéger la famille. A la protection d’origine légale, s’ajoute éventuellement une protection conventionnelle. Le législateur offre ainsi un espace de liberté à la volonté privée, même si l’exercice de celle-ci doit aboutir à réduire le gage du créancier. L’ensemble de ces dispositions protectrices entre donc nécessairement en conflit avec le droit à l’exécution des créanciers et conduit à s’interroger sur la légitimité de l’atteinte qui en résulte. Il apparait que dans certains cas l’équilibre entre la garantie de l’effectivité du droit à l’exécution forcée du créancier et la protection légitime du patrimoine de la famille est respecté, alors que dans d’autres, il est largement menacé, voire bouleversé. Et c’est alors toute l’économie du droit de l’exécution forcée qui est remise en question / The right to enforced performance offers creditors legal remedies for forcing defaulting debtors to perform their obligations. However, this relationship of obligation is less a tie between two people as it is a tie between two sets of assets. This explains why obligations are performed in respect of the property of the debtor. Performance should thus be entirely extraneous to the debtor's family situation and concern only the debtor's personal assets. Yet despite the fact that families do not have legal personality, "community property" (patrimoine familial) commonly comes into play. In the broad sense of the term, "community property" is thus necessarily of interest to third-party creditors. Certain property is afforded special protection generally intended to protect the family. In addition to legal protection, contractual protection may also apply. The legislation in this area thus allows for a certain degree of flexibility with respect to private will, even if it ultimately reduces a creditor's claim. This protection thus necessarily conflicts with the creditor's right to performance and raises the question of the legitimacy of the interference it causes. In some cases, the balance is maintained between guaranteeing creditors' ability to exercise their right to enforced performance and ensuring legitimate protection of family assets. In other cases, however, this balance is threatened or even upset, calling the entire tenor and intent of the right to enforced performance into question
78

Stress and Seizures : Behavioural Stress-Reduction Interventions’ Efficiency in Lowering Seizure Frequency

Larsson, Mathias January 2019 (has links)
Epilepsy is the most common, chronic, serious neurological disease in the world, with an estimated 65 million people affected worldwide. Recent studies on people diagnosed with epilepsy suggest that stress might trigger epileptic seizures. Interventions aimed at lowering stress might be able to reduce the risk for epileptic seizures among epileptics. In an attempt to explore this possibility, I conducted a systematic review addressing the efficacy of behavioral interventions targeted at lowering stress on seizure frequency among an epileptic population. This article also investigated the efficacy of these interventions on lowering self-perceived stress in the same population. Three databases were searched for obtaining 54 references. After a systematic filtering process, a set of 2 studies was retained after the full search procedure. The results suggest stress-reducing behavioral interventions do not have any statistically significant effects on lowering seizure frequency but have a statistically significant effect on lowering self-perceived stress ratings among an epileptic population. The small but promising results from trials and systematic reviews not included in this review warrant further research into the topic. Limitations regarding search procedure included studies and consideration for further research and reading for the presented topics are discussed.
79

Cognitive Rhythm Generators for Modelling and Modulation of Neuronal Electrical Activity

Zalay, Osbert C. 06 December 2012 (has links)
An innovative mathematical architecture for modelling neuronal electrical activity is presented, called the cognitive rhythm generator (CRG), wherein the proposed architecture is a hybrid model comprised of three interconnected stages, namely: (1) a bank of neuronal modes; (2) a ring device (limit-cycle oscillator); and (3) a static output nonlinearity (mapper). Coupled CRG networks are employed to emulate and elucidate the dynamics of biological neural networks, including the recurrent networks in the hippocampus. Several species of ring devices are described and investigated, including the clock, labile clock, hourglass and multistable ring systems, and their applications to neuronal modelling explored. Complexity measures such as the maximum Lyapunov exponent, correlation dimension and detrended fluctuation analysis are applied to compare model and biological records and validate the CRG methodology. The basis of neural coding is also examined in mathematical detail, with particular regard to its description by Volterra-Wiener kernel formalism, from which the neuronal modes are derived. Applications to theta-gamma coding are discussed. Further on in the thesis, a CRG epileptiform network model of spontaneous seizure-like events (SLEs) is developed and used as a platform to test neuromodulation approaches for seizure abatement. (Neuromodulation mentioned here refers to methods involving electrical stimulation of neural tissue for therapeutic benefit). Spontaneous SLE transitions in the epileptiform network are shown to be related to the mechanism of intermittency, as determined by examining the state space dynamics of the model. The onset of SLEs is associated with increased network excitability and decreased stability, consistent with experimental results from the low-magnesium/high-potassium in vitro model of epilepsy. Lastly, a novel strategy for therapeutic neuromodulation is presented wherein a coupled CRG network (called the “therapeutic network”) is interfaced with the epileptiform network model, forming a closed loop for responsive, biomimetic neuromodulation of the epileptiform network. Relevance to clinical applications and future work is discussed.
80

Cognitive Rhythm Generators for Modelling and Modulation of Neuronal Electrical Activity

Zalay, Osbert C. 06 December 2012 (has links)
An innovative mathematical architecture for modelling neuronal electrical activity is presented, called the cognitive rhythm generator (CRG), wherein the proposed architecture is a hybrid model comprised of three interconnected stages, namely: (1) a bank of neuronal modes; (2) a ring device (limit-cycle oscillator); and (3) a static output nonlinearity (mapper). Coupled CRG networks are employed to emulate and elucidate the dynamics of biological neural networks, including the recurrent networks in the hippocampus. Several species of ring devices are described and investigated, including the clock, labile clock, hourglass and multistable ring systems, and their applications to neuronal modelling explored. Complexity measures such as the maximum Lyapunov exponent, correlation dimension and detrended fluctuation analysis are applied to compare model and biological records and validate the CRG methodology. The basis of neural coding is also examined in mathematical detail, with particular regard to its description by Volterra-Wiener kernel formalism, from which the neuronal modes are derived. Applications to theta-gamma coding are discussed. Further on in the thesis, a CRG epileptiform network model of spontaneous seizure-like events (SLEs) is developed and used as a platform to test neuromodulation approaches for seizure abatement. (Neuromodulation mentioned here refers to methods involving electrical stimulation of neural tissue for therapeutic benefit). Spontaneous SLE transitions in the epileptiform network are shown to be related to the mechanism of intermittency, as determined by examining the state space dynamics of the model. The onset of SLEs is associated with increased network excitability and decreased stability, consistent with experimental results from the low-magnesium/high-potassium in vitro model of epilepsy. Lastly, a novel strategy for therapeutic neuromodulation is presented wherein a coupled CRG network (called the “therapeutic network”) is interfaced with the epileptiform network model, forming a closed loop for responsive, biomimetic neuromodulation of the epileptiform network. Relevance to clinical applications and future work is discussed.

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