No description available.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-03-29T13:17:55Z No. of bitstreams: 1 Emerson de Oliveira Dantas.pdf: 321375 bytes, checksum: e7a1908ccaf8bcb9ee0df5fdb308d1d3 (MD5) / Made available in DSpace on 2017-03-29T13:17:55Z (GMT). No. of bitstreams: 1 Emerson de Oliveira Dantas.pdf: 321375 bytes, checksum: e7a1908ccaf8bcb9ee0df5fdb308d1d3 (MD5) Previous issue date: 2014-08-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work is motivated by the Cauchy Functional Equation f (x + y) = f (x) .f (y), characteristic of the exponential function. To arrive at this equation we will begin our study of the definitions and statements of the Exponent Properties Real Power, particularly in the case in which the power exponent is irrational, besides doing a pedagogical proposal on teaching potentiation, Characterization of the Exponential Function and Functional Equation Linear Cauchy. / Este trabalho tem por motivação a Equação Funcional de Cauchy f(x + y) = f(x).f(y), característica da Função Exponencial. Para chegarmos a essa equação iniciaremos o nosso estudo pelas definições e demonstrações das Propriedades da Potência de Expoente Real, destacando o caso em que a Potência tem Expoente Irracional, além de fazermos uma proposta pedagógica sobre o ensino de Potenciação, Caracterização da Função Exponencial e Equação Funcional Linear de Cauchy

La cellule de Purkinje (CP) est la seule sortie anatomique du cortex cérébelleux. Des études récentes ont montré que les récepteurs NMDA (NMDA-R) jouaient un rôle essentiel dans le Depression à long terme (DLT) à la synapse entre les fibres parallèles (FP) et les CPs. Les NMDA-Rs pourraient jouer un rôle prépondérant dans l’intégration des informations somato-sensorielles des FPs et ainsi contribuer au rôle du cervelet dans l'apprentissage moteur. Nous montrons que les NMDA-Rs sont fonctionnels et recrutés uniquement lors de patrons de décharges des FPs haute fréquences. Ces résultats étant potentiellement liés aux propriétés biophysiques des NMDA-Rs, nous avons démontré que la PLT dépend des NMDA-Rs comportant les sous unité GluN2A et que l'expression post synaptique de la plasticité s'effectuait à travers une diffusion anterograde du monoxyde d'azote (MA). De plus, nous avons confirmé et disséqué les propriétés de filtre passe haut des NMDA-Rs in vivo et in vitro.Nous avons montré que la PLT nécessitait des trains d'activité des FPs plus long que dans le cadre de la DLT, nous postulons que la quantité de MA produite est plus importante lors de l'induction de PLT. Utilisant nos données, nous avons implémenté un model mathématique de plasticité à la synapses FP-CP pouvant prédire le signe de plasticité synaptique selon les patrons d'activité rencontrés par cette synapse. / Synaptic plasticity is thought to be the cellular mechanism underlying learning and memory and has been the subject of intense experimental and theoretical research. The experimental work has led to detailed knowledge of the receptors and signalling pathways involved in the induction of different types of synaptic plasticity. In parallel, theoretical studies have built ’plasticity rules’, formal descriptions linking spike timings to changes in synaptic efficacy, such as the spike-timing-dependent plasticity (STDP) rule [Gerstner et al., 1996, Song et al., 2000]. However, these plasticity rules are generally quite abstract and their link to the underlying biophysical mechanisms is often unclear. The best known mechanisms in synaptic plasticity are linked to N-methyl-D-aspartate receptor (NMDA-R) function. NMDA-Rs are biophysical coincidence detectors of glutamate and membrane depolarization [Mayer et al., 1984, Nowak et al., 1984]. The activation of postsynaptic NMDA-Rs defines learning rules where the relative timing of pre- and post-synaptic activity is a key parameter [Debanne et al., 1994, Nevian and Sakmann, 2006, Sjostrom et al., 2003]. In the few cases where the participation of presynaptic NMDA-Rs has been proposed, these have invariably been involved in presynaptically-expressed LTD [Rodríguez-Moreno and Paulsen, 2008b, Sjostrom et al., 2003]. Cerebellar parallel fibre-Purkinje cell (PF–PC) synaptic plasticity follows non-Hebbian plasticity rules. We have previously reported that PF-PC LTD induction needs PF bursting activity (at least pairs of spikes) [Bidoret et al., 2009] and is linked to the presence of presynaptic NMDA-Rs [Casado et al., 2002b]. In this thesis, we set out to characterise the activity requirements for bidirectional synaptic plasticity in young and adult animals, and to investigate the signalling pathways involved. Surprisingly, we found that LTP induction shares many properties with LTD induction, including a similar frequency-dependence for presynaptic activity and an absolute requirement for NMDA-R activation and NO production. However, LTP requires a different source of post-synaptic calcium increase [Ly et al., 2013a]. In contrast with other synapses [Bender et al., 2006, Fino, 2010], our data indicate that both LTP and LTD share signalling mechanisms. These involve presynaptically produced NO and postsynaptic Ca rises. Supporting the notion that the frequency dependence of plasticity arises from the involvement of presynaptic NMDA-Rs, we provide the first direct evidence for Ca influx through presynaptic NMDA-Rs in PFs in young and adult animals, settling a long-lasting controversy [Bidoret et al., 2009, Casado et al., 2002a, Shin and Linden, 2005a, Wang et al., 2014a]. Based on our data, we propose a novel mechanistic plasticity rule. This deliberately parsimonious rule can be used to interpret and predict the plasticity arising from arbitrary patterns of PF and climbing fibre (CF) activity. Our results support the notion that bidirectional synaptic plasticity depends on multi-spike activity patterns in an intricate fashion [Bidoret et al., 2009, Froemke and Dan, 2002, Pfister and Gerstner, 2006, Sjöström et al., 2001].

in English This dissertation studies su xal derivation of adjectives from nouns in French. It is based on a lexicon of about 15, 000 adjectives, 40% of which may be considered deno- minal. I rst present the data under investigation. I describe the Dénom database, which was derived from large scale lexica. In order to assess the position of denominal adjectives in the more general adjectival system, I present a classi cation of French adjectives on the basis of their morphological properties. In the process, I spot cases where the fringes of the class of denominals are unclear, and question the distributional and semantic co- hesion of the class. I nally review di erent types of formal or semantic mismatches between the adjective and its base noun. In a second step, I present a study of the formal and semantic properties of a subset of denominal adjectives where the morphological relation between base and derivative is regular. This subset is selected on the basis of the type frequency of formal patterns of alternation between base and derivative. I describe the phonological and morpholo- gical properties of base nouns, with the aim of uncovering factors that play a role in the formation of adjectives. This leads to the observation of morphological niches, that is, cases where the presence of a...

The current investigation was an examination of the kinetic and kinematic characteristics of the back squat using accentuated eccentric loading (AEL) and cluster set programming strategies. Trained male subjects (age = 26.1 ± 4.1 years, height = 183.5 ± 4.3 cm, body mass = 92.5 ± 10.5 kg, back squat to body mass ratio = 1.8 ± 0.3) volunteered to complete four different load condition sessions involving traditionally loaded straight sets (TL), traditionally loaded cluster sets (TLC), AEL cluster sets (AEC), and AEL straight sets where only the first repetition of each set used eccentric overload (AEL1). The use of AEL increased eccentric work (WECC) and eccentric rate of force development (RFDECC) but did not result in the expected potentiation of subsequent concentric output. Interrepetition rest, however, appears to have the largest influence on concentric peak power (PP), rate of force development (RFDCON), and average velocity (MV). Additionally, the current study was an investigation of the efficacy of novel methods of ultrasonography technique that can be applied to monitoring training response. Compared to lying measures of the vastus lateralis (VL), standing ultrasonography measures of muscle thickness (MT), pennation angle (PA), and cross-sectional area (CSA) were more strongly and abundantly correlated with dynamic and isometric strength performance. Finally, the present study was an exploration of the genetic underpinnings of performance outcomes and muscle phenotypic characteristics. The polymorphisms of two candidate genes (ACTN3, ACE) typical of strength-power athletes were used. ACTN3 RR tended to result in greater type II fiber CSA and alter maximal strength, while ACE DD tended to influence RFD through the presence of more favorable type II-to-type I CSA ratios. Overall, the current investigation provided valuable insight into the characteristics of advanced programming tactics. Furthermore, the ultrasonography measurement and genetic aspects of the current investigation may serve as a framework to inform monitoring practice and generate hypotheses related to the training process.

Grundtanken med detta arbete är att se om utomhuspedagogik möjligtvis främjar lärandet och om det går att finna stöd inom neurologisk forskning för att ta reda på om lärandet stimuleras vid användandet av utomhusundervisning. Undersökningar har genomförts för att se om lärare och elevers syn på utomhusundervisning sammanfaller. Arbetet bygger på litteraturstudier, intervjuer, en observationsstudie, samt enkätundersökningar för att besvara forskningsfrågorna. I denna studie har det framkommit att utomhusundervisning främjar lärandet, främst beroende på de multipla sinnesintryck som utomhusvistelsen skapar. Denna iakttagelse stöds även av neurologisk och pedagogisk forskning. Det har även framkommit att lärare och elever tycker att utomhusundervisning är ett viktigt och positivt inslag i undervisningen.

Long-term potentiation (LTP) and depression (LTD) are activity dependent long-lasting changes in synaptic efficacy and have been proposed as mechanisms for learning and memory. Although the exact relationship of LTP and LTD to memory is not known, they do share some properties and mechanisms that relate to memory, such as the strengthening and weakening of synapses. LTP and LTD have been studied extensively in hippocampal brain-slice preparations, due to its relatively organized structure, ease of induction, and its critical function in memory storage. Less work has been done in the neocortex despite the belief that it is heavily involved in the storage of long-term memories. Activity dependent plasticity has also been demonstrated in the basal ganglia in vivo and in vitro, but the results have been somewhat inconsistent. The experiments presented in this thesis explore a novel form of neural plasticity in two excitatory pathways (corticostriatal and thalamocortical) of the basal ganglia motor loop in the intact brain in awake, freely behaving rats. In thalamocortical slice preparations, simultaneous presynaptic stimulation and postsynaptic depolarization can induce L TP in animals prior to the critical period. However the results presented in this thesis show that applied stimulation to the thalamocortical pathway failed to produce either LTP or LTD in the awake freely moving animal.Corticostriatal LTD has been shown in slice preparations following direct tetanic stimulation of the striatum. In the current experiment, cortical stimulation failed to induce LTD although there was an observable decrease in the evoked potential following low-frequency stimulation. Corticostriatal L TP has been shown to depend on the type of stimulation applied. High-frequency and theta burst stimulation produced long-lasting changes in response amplitude in the corticostriatal pathway, with theta burst stimulation appearing to be the more effective stimulation protocol for inducing LTP in both the early and late components. Paired stimulation of the substantia nigra pars compacta and cortex indicated a modulatory action of dopamine on corticostriatal synaptic plasticity. Pairing led to a stable increase in the amplitude of LTP of both early and late components. We also report that a temporal relationship exists in the striatum with respect to the release of nigral dopamine and cortical glutamate. Simultaneous stimulation produced a more robust L TP compared to the two other conditions in which there was an applied stimulation delay to either the corticostriatal or nigrostriatal pathway. The results demonstrate the mechanistic differences, not only between the thalamocortical and corticostriatal pathways, but also slice and anesthetized preparations. The results also emphasize the need for further study on mechanisms of L TP and LTD in the various excitatory and inhibitory pathways of the basal ganglia motor loop. / Thesis / Doctor of Philosophy (PhD)

No / Age is characterized by deficits in synaptic function identified by decreased performance of aged animals in spatial learning tasks and reduced ability of animals to sustain long-term potentiation (LTP). Several cellular and molecular events are correlated with these deficits, many of which are indicative of cell stress. Thus there is evidence of age-related neuroinflammatory stress and oxidative stress and these have been linked with microglial activation which is likely to be primarily responsible for the age-related increase in production of proinflammatory cytokines and reactive oxygen species. It is significant that agents which decrease microglial activation are commonly associated with restoration of function. We set out to examine whether the n-3 polyunsaturated fatty acid docosapentaenoic acid (DPA), which is a metabolite of eicosapentaenoic acid (EPA), could modulate the age-related increase in microglial activation and the associated increase in oxidative changes and therefore impact on synaptic function in aged rats. We demonstrate that DPA possesses neurorestorative effects and is capable of downregulating microglial activation. The data show that it also decreases the coupled activation of sphingomyelinase and caspase 3, probably as a result of its ability to decrease age-related oxidative changes, and consequently attenuates the age-related decrease in spatial learning and LTP.

Xie, Hui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 91-116). / Abstracts in English and Chinese. / CONTENTS --- p.I / ACKNOWLEDGEMENTS --- p.i / ABSTRACT --- p.ii / 中文摘要 --- p.v / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Overview of the Study --- p.1 / Chapter 1.2 --- Obstructive Sleep Apnea --- p.4 / Chapter 1.2.1 --- Epidemiology --- p.5 / Chapter 1.2.1.1 --- Prevalence --- p.5 / Chapter 1.2.1.2 --- Risk Factors --- p.6 / Chapter 1.2.2 --- Pathogenesis --- p.8 / Chapter 1.2.3 --- Pathophysiologic Consequences --- p.9 / Chapter 1.2.4 --- Diagnosis --- p.12 / Chapter 1.2.5 --- Treatment --- p.13 / Chapter 1.3 --- Memory and Long-term Potentiation --- p.15 / Chapter 1.3.1 --- Memory --- p.15 / Chapter 1.3.1.1 --- Classification of Memory --- p.15 / Chapter 1.3.1.1 --- Physiology of Memory --- p.17 / Chapter 1.3.2 --- Hippocampus --- p.18 / Chapter 1.3.2.1 --- Anatomy --- p.18 / Chapter 1.3.2.2 --- Hippocampus and Memory --- p.20 / Chapter 1.3.3 --- Long-term Potentiation (LTP) --- p.20 / Chapter 1.3.3.1 --- Discovery of LTP --- p.21 / Chapter 1.3.3.2 --- Types of LTP --- p.22 / Chapter 1.3.3.3 --- Properties of NMDA-LTP --- p.23 / Chapter 1.3.3.4 --- Early Phase LTP and Mechanism --- p.24 / Chapter 1.3.3.5 --- Late Phase LTP and Mechanism --- p.28 / Chapter 1.3.3.6 --- Important Factors in Long-term Potentiation --- p.29 / Chapter 1.4 --- Brain-derived Neurotrophic Factor (BDNF) --- p.33 / Chapter 1.4.1 --- Neurotrophins --- p.33 / Chapter 1.4.2 --- Structure and Expression of BDNF --- p.36 / Chapter 1.4.3 --- BDNF and Synaptic Plasticity --- p.37 / Chapter 1.4.3.1 --- BDNF and E-LTP --- p.38 / Chapter 1.4.3.2 --- BDNF and L-LTP --- p.39 / Chapter CHAPTER 2 --- METHODS --- p.43 / Chapter 2.1 --- Animal model of Obstructive Sleep Apnea --- p.43 / Chapter 2.1.1 --- Chronic Intermittent Hypoxia --- p.43 / Chapter 2.1.2 --- Bodyweight During Hypoxia Treatment --- p.47 / Chapter 2.2 --- Electrophysiological Experiments --- p.47 / Chapter 2.2.1 --- Brain Slice Preparation --- p.47 / Chapter 2.2.2 --- Multi-electrode Recording Setup (MED64) --- p.48 / Chapter 2.2.3 --- Slice Superfusion --- p.51 / Chapter 2.3.4 --- Field Potential Recordings --- p.53 / Chapter 2.3.5 --- LTP Induction Protocol --- p.55 / Chapter 2.3 --- Stereotaxic Surgery --- p.57 / Chapter 2.4 --- Drugs and Data Analysis --- p.58 / Chapter CHAPTER 3 --- RESULTS --- p.59 / Chapter 3.1 --- Validation of the OSA model --- p.59 / Chapter 3.2 --- Optimization for Studies of Early and Late-phase LTP by MED64 --- p.60 / Chapter 3.2.1 --- Optimization of Brain Slices --- p.60 / Chapter 3.2.2 --- Optimization of Field Potential Recording --- p.62 / Chapter 3.2.3 --- Optimization for LTP Study --- p.65 / Chapter 3.3 --- Effect of Intermittent Hypoxia on Hippocampal LTP --- p.68 / Chapter 3.3.1 --- Early-phase LTP (E-LTP) --- p.68 / Chapter 3.3.2 --- Late-phase LTP (L-LTP) --- p.71 / Chapter 3.4 --- Effect of BDNF on Intermittent Hypoxia-induced LTP Impairment --- p.75 / Chapter 3.4.1 --- BDNF Rescues LTP Impairment --- p.75 / Chapter 3.4.2 --- BDNF prevents LTP Impairment --- p.78 / Chapter CHAPTER 4 --- DISCUSSION --- p.80 / Chapter 4.1 --- Chronic Intermittent Hypoxia Model of OSA in Mice --- p.80 / Chapter 4.2 --- Impairment of LTP Induced by Intermittent Hypoxia --- p.82 / Chapter 4.3 --- The role of BDNF in IH-induced Impairment in Hippocampal Synaptic Plasticity --- p.84 / Chapter 4.4 --- Future Studies --- p.89 / REFERENCE --- p.91

Spinal manipulative therapy (SMT) is a therapeutic procedure employed by various healthcare practitioners for alleviating acute and chronic musculoskeletal complaints. This form of treatment is also delivered to enhance the performance and augment the rehabilitation of athletes. However, despite research findings alleging the strength-modulating effects of SMT alongside numerous professional athletes’ positive anecdotal claims concerning its results, the physiological processes to explain its effects remain largely unexplained. Therefore, the purpose of this work was to investigate the effects of SMT in a college-aged sample population with two experiments. The first study examined the effect of SMT targeting the lumbosacral region on concentric force production of the knee extensors and flexors. A randomized, controlled, single-blind crossover design was utilized with 21 subjects. Isometric and isokinetic peak torques (Nm) were recorded during maximal voluntary isometric contractions (MVIC) or maximal voluntary contractions (MVC) post-treatment of either SMT or a sham manipulation. The second study incorporated the same experimental design with 20 subjects to examine the effects of SMT on central nervous system (CNS) excitability. This was accomplished by assessing postactivation potentiation (PAP), measured with the Hoffmann Reflex (H-reflex). PAP is an enhanced neuromuscular response to prior contractile activity, and the H-reflex is the electromyographic (EMG) recording of submaximal electrical stimulation of the Ia monosynaptic reflex pathway. Subsequent to SMT and/or a plantar flexion MVIC, EMG amplitudes and isometric twitch torque generation of the gastrocnemius and soleus muscles were recorded during tibial nerve stimulations. The results of the first study indicate that SMT did not produce a significant strength-modulating effect during isometric and isokinetic contractions of neither knee extension nor flexion. Similarly, the second study revealed that SMT immediately preceding the MVIC to induce PAP did not significantly increase H-reflex EMG amplitudes of either muscle or the simultaneous isometric twitch torque generation compared to the MVIC only. These data from both investigations suggest that SMT does not enhance strength or PAP. The positive anecdotal claims of athletes who utilize SMT may be due to other factors, such as the clinical efficacy of the treatment in addressing musculoskeletal injuries or a placebo effect.