Dissertations / Theses: 'Local Stimulation'

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Trauchessec, Vincent. "Local magnetic detection and stimulation of neuronal activity." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS301/document.

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L’activité cérébrale se traduit par des courants ioniques circulant dans le réseau neuronal.La compréhension des mécanismes cérébraux implique de sonder ces courants, via des mesures électriques ou magnétiques, couvrant différentes échelles spatiales. A l’échelle cellulaire, les techniques d’électrophysiologie sont maitrisées depuis plusieurs décennies, mais il n’existe pas actuellement d’outils de mesure locale des champs magnétiques engendrés par les courants ioniques au sein du réseau neuronal. La magnéto-encéphalographie(MEG) utilise des SQUIDs(Superconducting QUantum Interference Devices)fonctionnant à très basse température, placés en surface du crâne, qui fournissent une cartographie des champs magnétiques mais dont la résolution spatiale est limitée du fait de la distance séparant les capteurs des cellules actives. Le travail présenté dans cette thèse propose de développer des capteurs magnétiques à la fois suffisamment sensibles pour être capable de détecter le champ magnétique extrêmement faible générés par les courants neuronaux (de l’ordre de 10⁻⁹ T), et dont la géométrie est adaptable aux dimensions des cellules, tout en fonctionnant à température ambiante. Ces capteurs,basés sur l’effet quantique de magnétorésistance géante (GMR, sont suffisamment miniaturisables pour être déposés à l’extrémité de sondes d’une finesse de l’ordre de 100 μm. L’utilisation de capteurs GMR pour la mesure de signaux biomagnétiques fut d’abord testée lors d’expériences in-vitro, réalisées sur le muscle soléaire de souris. Ce système biologique a été choisi pour sa simplicité,rendant la modélisation accessible, ainsi que pour sa robustesse, permettant d’avoir des résultats fiables et reproductibles. Le parfait accord entre les prédictions théoriques et les signaux magnétiques mesurés valide cette technologie. Enfin, des expériences in vivo dans le cortex visuel du chat ont permis de réaliser la toute première mesure de la signature magnétique de potentiels d’action générés par des neurones corticaux, ouvrant la voie à la magnétophysiologie
Information transmission in the brain occurs through ionic currents flowing inside the neuronal network. Understanding how the brain operates requires probing this electrical activity by measuring the associated electric or magnetic field. At the cellular scale, electrophysiology techniques are well mastered, but there is no tool to perform magnetophysiology. Mapping brain activity through the magnetic field generated by neuronal communication is done via magnetoencephalography (MEG). This technique is based on SQUIDs (Superconducting Quantum Interference Devices) that operate at liquid Helium temperature. This parameter implies to avoid any contact with living tissue and a shielding system that increases the distance between the neurons and the sensors, limiting spatial resolution. This thesis work aims at providing a new tool to performmagnetic recordings at the neuronal scale. The sensors developed during this thesis are based on the Giant Magneto-Resistance (GMR) effect. Operating at room temperature, they can be miniaturize and shaped according to the experiment, while exhibiting a sensitivity that allows to measure amplitude of 10⁻⁹ T. Before targeting neurons, the use of GMR-based sensors for magnetic recordings of biological activity has been validated through invitro experiments on the mouse soleus muscle. This biological system has been chosen because of its simple organization, allowing for a realistic modelling, and for its robustness, in order to get reliable and replicable results. The perfect agreement between the measurements and the theoretical predictions represents a consistent validation of the GMR technology for biological applications. Then a specially adapted needle-shaped probe carrying micron-sized GMR sensors has been developed for in-vivo experiment in cat visual cortex. The very first magnetic signature of action potentials inside the neuropil has been measured, paving the way towards magnetophysiology

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Mallik, Adeil. "Design and fabrication of a transparent microfluidic probe for local stimulation of neurons." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119686.

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The answers to many key neurological questions require the capability of localized chemical/drug delivery within cell/brain slice tissue culture with concomitant high-resolution optical imaging. The microfluidic probe (MFP) offers the capability of localized chemical/drug delivery. However, in its current design and implementation, the MFP is incompatible with upright microscope systems and thus incompatible with high-resolution water immersion microscope objectives lenses, which are needed to image small morphological features such as dendrites and synapses. The main objective of my research was to design and fabricate a new MFP that is compatible with the upright microscope system to further explore neuronal applications, which require local stimulation of neurons. The new upright microscope MFP was designed and two fabrication processes using a UV curable photopolymer (Norland Optical Adhesive or Off-stoichiometry thiolene) were developed to fabricate it. Two configurations of the MFP were produced, one with a bent tip, and the other with a straight mesa, with the rapid prototyping fabrication process. Preliminary characterization and proof of concept of local stimulation was done on the straight mesa MFP. In summary a new tool for local neuron stimulation was developed that offers wide range applications in neuroscience. In the thesis I explore its future use in determining the mechanisms of post-traumatic epilepsy.
Les réponses à de nombreuses questions neurologiques clés requièrent la capacité de livraison localisée de produits chimiques/médicaments dans la culture de tranches de tissus cellulaires / cerveau avec l'imagerie optique à haute résolution concomitante. La sonde microfluidique (MFP) offre la capacité de distribution localisée de produits chimiques / médicaments. Cependant, dans sa conception et sa mise en œuvre actuelle, la MFP est incompatible avec les systèmes de microscope droit et donc incompatible avec la microscopie à haute résolution ou les objectifs sont immergés dans de l'eau, qui est nécessaire pour l'acquisition d'images de petites caractéristiques morphologiques telles que des dendrites et des synapses. L'objectif principal de ma recherche était de concevoir et fabriquer une nouvelle MFP qui est compatible avec le système de microscopie droit pour l'employer dans des applications neuronales, qui nécessitent une stimulation locale des neurones. La nouvelle MFP pour microscope droit a été conçu et deux procédés de fabrication utilisant un photopolymère curable sous UV (Norland adhésif optique ou thiolène Off-stoechiométrie) ont été développés pour la fabriquer. Deux configurations de la MFP ont été produites, l'une avec une pointe coudée, et l'autre avec une mesa droite, à travers un procédé de fabrication de prototypage rapide. Une caractérisation préliminaire et des expériences de preuve de concept ou la stimulation locale a été effectuée avec la MFP à mesa droite. En résumé, un nouvel outil pour la stimulation locale de neurones a été développé qui offre de larges applications en neurosciences. Dans la thèse j'explore son utilisation future dans la détermination des mécanismes d'épilepsie post-traumatique.

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Souron, Robin. "Adaptations fonctionnelles et nerveuses à l'entraînement par vibration locale : du sujet sain à la rééducation." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSES055/document.

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La recherche de méthodes permettant de lutter contre le déconditionnement neuromusculaire à la suite par exemple d’une opération chirurgicale ou d’une immobilisation prolongée intéresse la communauté scientifique depuis de nombreuses années. Ce projet visait à proposer la technique de vibration locale (LV) comme une méthode alternative aux méthodes classiquement utilisées (e.g. vibration corps entier, stimulation électrique neuromusculaire) pour lutter contre ce déconditionnement neuromusculaire. Le premier objectif de ce travail de thèse était de déterminer les effets d’une application aigüe de LV sur la fonction neuromusculaire des muscles fléchisseurs dorsaux et extenseurs du genou de sujets sains. Nos résultats montrent une modulation de l’excitabilité du système nerveux central en réponse à l’application aigüe de LV, ce qui nous a permis d’envisager de potentielles adaptations si cette technique était utilisée de façon répétée sur plusieurs semaines. Ainsi, la seconde orientation de ce travail était d’évaluer les effets d’une application chronique (entraînement) de LV sur les propriétés fonctionnelles (force, hauteur de saut) et nerveuses (mesurées par stimulation magnétique transcrânienne) de sujets sains, jeunes et âgés. Nos résultats ont montré qu’un entraînement par LV était efficace pour améliorer les capacités fonctionnelles de ces deux populations, ces gains s’accompagnant d’adaptations nerveuses. Ces travaux nous ont alors conduits à la mise en place d’une dernière étude (en cours) à visée clinique, qui évaluait l’efficacité de LV en rééducation post-ligamentoplastie du ligament croisé antérieur du genou
There is a need to find new methods to limit neuromuscular deconditioning that occurs after a surgery or prolonged immobilization. This thesis aimed to assess local vibration (LV) training as an alternative to methods classically used (e.g. whole body vibration, neuromuscular electrical stimulation) to fight against neuromuscular deconditioning. The first aim of this project was to determine the effects of a 30-min acute exposure to LV on the neuromuscular function of dorsiflexor and knee extensor muscles in a healthy population. Our results showed that acute LV intervention changed central nervous system excitability, allowing us to consider long-term adaptations to prolonged LV. Thus, the second aim of this thesis was to assess the effects of a chronic application (training) of LV on functional (maximal strength, squat jump performance) and neural (assessed with transcranial magnetic stimulation) properties of healthy young and old subjects. Our results showed that 4 to 8 weeks of LV increase functional capacities that were due to neural adaptations. Based on these results, an on-going study assessing the effectiveness of LV during a rehabilitation program for subjects who suffered from anterior cruciate ligament lesion has been proposed

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Robertazzi, Federica. "Real-time rejection of movement-related artifacts in subthalamic nucleus local field potential recordings during adaptive Deep Brain Stimulation." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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La stimolazione cerebrale profonda (DBS) è una tecnica utilizzata in clinica per trattare alcune patologie come la malattia di Parkinson (PD) tramite un rilascio locale di corrente alternata ad alta frequenza (> 100 Hz), grazie all’utilizzo di elettrodi impiantati nei gangli della base durante una procedura di chirurgia stereotassica. Negli ultimi anni indagini neurofisiologiche svolte con la DBS hanno inoltre consentito la scoperta di potenziali marcatori neurali caratteristici del PD e il loro utilizzo per una stimolazione definita adattativa (aDBS) in cui l’ampiezza dello stimolo in tensione viene controllato dallo stato attuale del paziente. Una versione di aDBS è stata sviluppata da Newronika s.r.l. che è riuscita a implementare un algoritmo closed-loop basato sulla potenza delle oscillazioni beta come variabile di controllo del voltaggio della DBS. Numerosi studi con la aDBS sono stati effettuati prima su pazienti con PD a riposo e poi durante alcuni task di vita quotidiana come il cammino. Durante questi test è emerso che la aDBS non riusciva a performare bene durante l’attività di cammino per la presenza di artefatti a bassa frequenza (1-8 Hz) sul segnale LFP causati principalmente dal contatto del tallone sul terreno all’inizio della fase di stance del passo. Lo scopo di questa tesi è stato quello di proporre un algoritmo innovativo basato sulla Empirical Mode Decomposition per la rimozione di tale artefatto senza inficiare la performance della aDBS. L’algoritmo basato sulla EMD è stato capace di eliminare il rumore in maniera efficace, rimuovendo potenza spettrale non utile nella banda dell’artefatto e mantenendo intatto il contenuto in beta (fondamentale per la riuscita della aDBS). Inoltre, in questo lavoro è stata proposta un’implementazione real-time dell’algoritmo di pulizia del segnale nello stesso microcontrollore (MSP430FR5969) usato nel dispositivo AlphaDBS V-Imp di Newronika con la prospettiva di poter esser integrato in quest’ultimo in futuro.

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Holland, Peter James. "Frequency-domain and nonlinear analysis of local field potentials and clinical efficacy of deep brain stimulation for complex tremors." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558309.

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Recent years have seen increasing interest in the application of ideas and techniques from the field of dynamical systems theory to neurological signals. However, the applicability of these potentially powerful methods to basal ganglia local field potentials is yet to be established. This thesis attempts to prove the merit of employment ofthese methods in the analysis of signals which represent one of the few chances to record subcortical electropbysiological activity in the awake human. Tbe nonlinear analysis technique of Recurrence Quantification Analysis was employed due to its robustness to noise and nonstationarity. The presence of non linear dynamics in local field potentials recorded from the subtbalamic nucleus, globus pallidus and motor thalamus of movement disorders patients is established for the first time using surrogate data testing, validating the suitability of this technique. Indicating its potential capability, Recurrence Quantification Analysis proves effective in discriminating local field potentials recorded from the globus pallidus and the subthalamic nucleus where spectral measures do not. Alterations in linear and nonlinear aspects of subthalamic nucleus local field potentials due to the effects of dopaminergic medication are also demonstrated. Evidence for differences in the pattern of coherence between simultaneously recorded globus pallidus and thalamic local field potentials between dystonic and tremulous patients is provided and related to bivariate nonlinear statistics. The clinical efficacy of Deep Brain Stimulation is investigated in a group of patients suffering from complex tremor resulting from acquired brain injury, with significant postoperative improvement demonstrated. However, the inability of Deep Brain Stimulation to treat ataxia, which is also a common problem in the treatment of tremor associated with multiple sclerosis, is noted in this group. In order to improve multiple sclerosis patient selection a method is developed based on the power spectrum of the electromyogram and shown to correlate significantly with clinical outcome.

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Ebrahimian, Haleh [Verfasser]. "Local stimulation of cell signals in single cells / Haleh Ebrahimian. Fakultät für Physik - AG Dünne Schichten & Physik der Nanostrukturen." Bielefeld : Universitätsbibliothek Bielefeld, Hochschulschriften, 2012. http://d-nb.info/102842731X/34.

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Ahmad, Bahuri Nor Faizal. "The effects of volitional breathing and carbon dioxide inhalation on human local field potentials." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:a5431969-0a68-4450-9a12-f5a3288d3730.

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Breathing is an automatic process that we hardly pay any attention to in our daily life. As a social species, we interact using body movement, speech and emotion and these actions require modification of the respiratory pattern. While we understood how the respiratory rhythm is generated, we do not have clear evidence on how higher cortical signals modulate the respiratory pattern. The deep cortical structures in the human brain are inaccessible under normal circumstances, and deep brain stimulation electrode recordings offer an opportunity to understand the neurophysiological interactions ofdeeper brain structures. In this thesis, I investigated deep brain stimulation recordings from implanted electrodes in chronic neuropathic pain subjects in the right and left anterior cingulate cortices, the ventral posterior lateral nucleus of the thalamus and periventricular gray region. The objectives of this research were to elucidate the feed-forward mechanisms of volitional breathing, cortical autonomic regulation, and to investigate whether any of the investigated nuclei haveany carbon dioxide-sensitive neurons which may encode respiratory sensation. The results show lateralisation of the cortical autonomic control whereby the left anterior cingulate exhibits increases in beta band activity (30 to 90 Hz) with cognition and vocalisation tasks. Meanwhile, right anterior cingulate activity increases with hyperoxia. Respiration using various carbon dioxide concentrations shows a constant rise in the alpha band (8 to 14 Hz) activity in the PVG which suggests a sensitive, nonspecific neuronal activity related to systemic carbon dioxide levels.

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Ocazionez, Sergio Andr?s Conde. "The influence of visual inter-hemispheric connections on spiking, assembly and LFP activities, and their phase relationship during figure-ground stimulation." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/17032.

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Made available in DSpace on 2014-12-17T15:29:22Z (GMT). No. of bitstreams: 1 SergioACO_TESE.pdf: 4589227 bytes, checksum: 062baf399b5377e444d02b747586f12b (MD5) Previous issue date: 2014-03-31
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
Desde os descobrimentos pioneiros de Hubel e Wiesel acumulou-se uma vasta literatura descrevendo as respostas neuronais do c?rtex visual prim?rio (V1) a diferentes est?mulos visuais. Estes est?mulos consistem principalmente em barras em movimento, pontos ou grades, que s?o ?teis para explorar as respostas dentro do campo receptivo cl?ssico (CRF do ingl?s classical receptive field) a caracter?sticas b?sicas dos est?mulos visuais como a orienta??o, dire??o de movimento, contraste, entre outras. Entretanto, nas ?ltimas duas d?cadas, tornou-se cada vez mais evidente que a atividade de neur?nios em V1 pode ser modulada por est?mulos fora do CRF. Desta forma, ?reas visuais prim?rias poderiam estar envolvidas em fun??es visuais mais complexas como, por exemplo, a separa??o de um objeto ou figura do seu fundo (segrega??o figura-fundo) e assume-se que as conex?es intr?nsecas de longo alcance em V1, assim como as conex?es de ?reas visuais superiores, est?o ativamente envolvidas neste processo. Sua poss?vel fun??o foi inferida a partir da an?lise das varia??es das respostas induzidas por um est?mulo localizado fora do CRF de neur?nios individuais. Mesmo sendo muito prov?vel que estas conex?es tenham tamb?m um impacto tanto na atividade conjunta de neur?nios envolvidos no processamento da figura quanto no potencial de campo, estas quest?es permanecem pouco estudadas. Visando examinar a modula??o do contexto visual nessas atividades, coletamos potenciais de a??o e potenciais de campo em paralelo de at? 48 eletrodos implantados na ?rea visual prim?ria de gatos anestesiados. Estimulamos com grades compostas e cenas naturais, focando-nos na atividade de neur?nios cujo CRF estava situado na figura. Da mesma forma, visando examinar a influ?ncia das conex?es laterais, o sinal proveniente da ?rea visual isot?pica e contralateral foi removido atrav?s da desativa??o revers?vel por resfriamento. Fizemos isso devido a: i) as conex?es laterais intr?nsecas n?o podem ser facilmente manipuladas sem afetar diretamente os sinais que est?o sendo medidos, ii) as conex?es inter-hemisf?ricas compartilham as principais caracter?sticas anat?micas com a rede lateral intr?nseca e podem ser vistas como uma continua??o funcional das mesmas entre os dois hemisf?rios e iii) o resfriamento desativa as conex?es de forma causal e revers?vel, silenciando temporariamente seu sinal, permitindo conclus?es diretas a respeito da sua contribui??o. Nossos resultados demonstram que o mecanismo de segmenta??o figurafundo se reflete nas taxas de disparo de neur?nios individuais, assim como na pot?ncia do potencial de campo e na rela??o entre sua fase e os padr?es de disparo produzidos pela popula??o. Al?m disso, as conex?es laterais inter-hemisf?ricas modulam estas vari?veis dependendo da estimula??o feita fora do CRF. Observamos tamb?m uma influ?ncia deste circuito lateral na coer?ncia entre potenciais de campo entre eletrodos distantes. Em conclus?o, nossos resultados d?o suporte ? ideia de um mecanismo complexo de segmenta??o figura-fundo atuando desde as ?reas visuais prim?rias em diferentes escalas de frequ?ncia. Esse mecanismo parece envolver grupos de neur?nios ativos sincronicamente e dependentes da fase do potencial de campo. Nossos resultados tamb?m s?o compat?veis com a hip?tese que conex?es laterais de longo alcance tamb?m fazem parte deste mecanismo
Since Hubel and Wiesel s pioneer finding a vast body of literature has accumulated describing neuronal responses in the primary visual cortex (V1) to different visual stimuli. These stimuli mainly consisted of moving bars, dots or gratings which served to explore the responses to basic visual features such as orientation, direction of motion or contrast, among others, within a classical receptive field (CRF). However, in the last two decades it became increasingly evident that the activity of V1 neurons can be modulated by stimulation outside their CRF. Thus, early visual areas might be already involved in more complex visual tasks like, for example, the segmentation of an object or a figure from its (back)-ground. It is assumed that intrinsic long-range horizontal connections within V1 as well as feedback connections from higher visual areas are actively involved in the figure-ground segmentation process. Their possible role has been inferred from the analysis of the spike rate variations induced by stimuli placed outside the CRF of single neurons. Although it is very likely that those connections also have an impact on the joined activity of neurons involved in processing the figure and on their local field potentials (LFP), these issues remain understudied. In order to examine the context-dependent modulation of those activities, we recorded spikes and LFPs in parallel from up to 48 electrodes in the primary visual cortex of anesthetized cats. We stimulated with composite grating and natural scene stimuli focusing on populations of neurons whose CRFs were situated on the foreground figure. In addition, in order to examine the influence of horizontal connections we removed the inter-hemispheric input of the isotopic contralateral visual areas by means of reversible cooling deactivation. We did so because i) the intrinsic horizontal connections cannot be easily manipulated without directly affecting the measured signals, ii) because inter-hemispheric connections share the major anatomical features with the intrinsic lateral network and can be seen as a functional continuation of the latter across the two hemispheres and iii) because cooling causally and reversibly deactivates input connections by temporarily silencing the sending neurons and thus enables direct conclusions on their contribution. Our results demonstrate that the figure-ground segmentation mechanism is reflected in the spike rate of single neurons, as well as in their LFP power and its phase-relationship to the spike patterns produced by the population. In addition "lateral" inter-hemispheric connections modulate spike rates and LFP power depending on the stimulation of the neurons CRF surround. Further, we observe an influence of this lateral circuit on field- field coherences between remote recording sites. In conclusion, our findings support the idea of complex figure-ground segmentation mechanism acting already in early visual areas on different time scales. This mechanism seems to involve groups of neurons firing synchronously and dependent on the LFP s phase. Our results are also compatible with the hypothesis that long-range lateral connections contribute to that mechanism

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Kalinauskaitė, Daiva. "Socialinių darbuotojų motyvacija ir jos skatinimas viešojo sektoriaus ir nevyriausybinio sektoriaus institucijose." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050604_192433-83995.

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Daiva Kalinauskaitė In the latest decades of the last century seeking rational use of finance, estimation of efficiency has become firmly established and the means of private activity efficiency and management have been put into practice. The decentralization of structure and self-government are indispensable means for perfection of management, discipline and control. Actually, it is measuring of the results of work and quality and determination of clear aims for organization units and individuals. The new public management witnesses the improvement of organizational power – “culture” and behavior but not mechanisms of organization or system are becoming the object of method estimation. Evaluation is becoming human behavior more and more in organizations, but not the way of control of organization behavior. Putting into practice human supply management methods, such as payment according results, the evaluation and certification of personnel, changes motivation, culture and regulations of the workers. It is very important for market now that the workers of budgetary and not governmental organizations would have equivalent conditions in order to avoid changing and demotivation. A research was carried out, the aim of which was to reveal the peculiarities of social workers’ motivation. In public sector stimulation system is regulated according to the laws; a more versatile stimulating system of not governmental sector gives a bigger efficiency of institutions and the... [to full text]

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Shimotake, Akihiro. "Direct Exploration of the Role of the Ventral Anterior Temporal Lobe in Semantic Memory: Cortical Stimulation and Local Field Potential Evidence From Subdural Grid Electrodes." Kyoto University, 2015. http://hdl.handle.net/2433/202675.

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Germishuys, Jurie J. "Free light chains in patients with HIV: establishing local reference ranges and their association with stage of disease, chronic antigen stimulation and the effect of Haart." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20173.

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Thesis (MMedSc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Background: Serum free light chains (FLC) are associated with imbalances in heavy and light chain production. Abnormal FLC ratios have been associated with risk of progression in certain diseases. Automated assays are available for their determination and they are used in the followup and management of patients with monoclonal gammopathies. Acceptable imprecision, specificity, accuracy and reproducibility between reagent batches is required to prevent under- or overestimation. Method validation is a standard process in every good laboratory to judge the acceptability of a new method. Reference intervals have been established in an older population, but it was considered important to verify these in our population. HIV is associated with B-cell dysfunction. As B-cell abnormalities are associated with disorders leading to monoclonal gammopathies, we postulated that the FLC levels and FLC ratio would be abnormal in HIV infected individuals. Methods and materials: Controls and pooled patient samples were used for the method validation study which included imprecision studies, linearity, recovery and interference studies, and method comparison studies, the latter compared our method to the same method used in another laboratory. For the reference interval study, blood was obtained from 120 healthy subjects. The following blood tests were performed: total protein, IgG, IgA, IgM, creatinine, protein electrophoresis, kappa FLC and lambda FLC. Using the kappa and lambda FLC results, a FLC ratio was determined. Three hundred and sixty-nine HIV positive subjects were then studied. The same tests were performed, as well as CD4+ counts and viral loads on the majority of them. Results: For the method validation study, precision, linearity and recovery was acceptable. Minimal interference was observed with haemolysis, lipaemia, bilirubin and rheumatoid factor. Our method showed comparable performance with the established method. For the reference interval study, all the creatinine values were normal, as were serum protein values. The serum protein electrophoreses were independently reviewed by 3 pathologists. Most were normal, with a few polyclonal increases seen, but no definite monoclonal bands. The 95% reference intervals for FLC’s as well as the FLC ratio were not statistically significantly different to the manufacturer’s recommendations. When examining the HIV positive study population, we found that FLC and FLC ratio were influenced by markers of HIV disease severity, such as CD4+ count, IgG, viral load, use of antiretroviral treatment and abnormal serum protein electrophoreses. Conclusion: The validation study of FLC showed excellent precision, acceptable bias, good linearity, good recovery and minimal interference, allowing routine introduction of the test. The 95% reference intervals obtained for our population were slightly higher than those recommended by the manufacturer. However, as most of the values fell within the manufacturer’s limits, we could accept the manufacturer’s recommended cut-offs. We found that FLC levels were definitely influenced by markers of HIV disease severity in our population and we postulate that they may be of use for follow-up of patients with HIV.
AFRIKAANSE OPSOMMING: Agtergrond: Serum vry ligte kettings (VLK) word geassosieer met ‘n wanbalans van ligte en swaar ketting produksie. Abnormale VLK ratios is geassosieer met ‘n risiko van verloop in sekere siektes. Geoutomatiseerde laboratorium toetse vir VLK is beskikbaar vir hul bepaling en word gebruik om pasiënte met monoklonale gammopatieë op te volg en te behandel. Aanvaarbare impresisie, spesifisiteit, akkuraatheid en herhaalbaarheid tussen reagens besendings is belangrik om onder- of oorbepaling te verhoed. Metode validasie is ’n standaard proses in elke goeie laboratorium om die aanvaarbaarheid van ’n nuwe metode te bepaal. Verwysingswaardes is al bepaal in ’n ouer populasie. Ons het besluit om die verwysingswaardes in ons populasie te bepaal. Mens-immuungebrekvirus (MIV) word geassosieer met B-sel disfunksie. Omdat B-sel abnormaliteite geassosieer word met afwykings wat tot monoklonale gammopatieë lei, het ons gepostuleer dat die VLK vlakke en VLK ratio abnormaal sal wees in MIV geïnfekteerde persone. Metodes en Materiale: Kontroles en pasiënt monsters is gebruik vir die metode validasie studie wat impresisie studies, lineariteit, herwinning, inmenging en metode korrelasie studies ingesluit het. In laasgenoemde geval is ons metode met dieselfde metode van ’n ander laboratorium vergelyk. Vir die verwysingswaardes studie is 120 gesonde persone se bloed gebruik. Die volgende toetse is bepaal: totale proteïen, IgG, IgA, IgM, kreatinien, proteïen elektroferese, kappa en lambda VLK. Die VLK ratio is bepaal deur die kappa en lambda resultate te gebruik. Driehonderd nege en sestig MIV-positiewe pasiente is gebruik vir die studie. Dieselfde toetse was gedoen, asook CD4+ tellings en virale ladings op die meerderheid van pasiente. Resultate: Vir die metode validasie studie, was presisie, lineariteit en herwinning aanvaarbaar. Minimale inmenging van hemolise, lipemie, bilirubien en rumatoïede factor is waargeneem. Ons metode het goed gekorreleer met die bepaalde metode. Die serum kreatinien en serum totale proteïen waardes was normaal tydens die verwysingswaardes studie. Die serum proteïen elektroferese was onafhanklik beoordeel deur 3 patoloë. Die meeste was normaal met enkele poliklonale verhogings, maar geen definitiewe monoklonale bande nie. Die 95% verwysings intervalle vir VLK en VLK ratio het nie statisties betekenisvol verskil van die vervaardiger se aanbevelings nie. In die studie van die MIV-positiewe studie populasie, het ons gevind dat VLK en VLK ratio beïnvloed word deur merkers van ernstige MIV siekte, soos CD4+ telling, IgG, virale lading, die gebruik van antiretrovale medikasie en abnormale serum proteïen elektroferese. Gevolgtrekking: Die validasie studie van VLK het uitstekende presisie, aanvaarbare partydigheid, goeie lineariteit, goeie herwinning en minimale inmenging gewys, wat die roetine instelling van die toets toegelaat het. Die 95% verwysingsintervalle wat vir ons populasie bepaal is, was effens hoër as die vervaardiger se aanbeveling. Die meeste van die waardes het egter binne die vervaardiger se limiete geval, dus kon ons die vervaardiger se afsnypunte aanvaar. Ons het gevind dat VLK vlakke definitief beïnvloed word deur merkers van die ernstigheidsgraad van MIV siekte in ons populasie en ons postuleer dat VLK van waarde kan wees met die opvolg van MIV pasiente.
NHLS
Harry Crossley for funding obtained

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Abuaisha, Murad S. "Géothermie profonde : stimulation de la perméabilité par fracturation hydraulique dans un cadre thermo-poroélastique." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI016/document.

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Ce travail concerne l'utilisation de la technique de Fracturation Hydraulique (FH) pour exploiter l'énergie géothermique des réservoirs profonds de roches sèches chaudes (HDR). La fracturation hydraulique est réalisée par injection de fluides géothermiques dans des réservoirs partiellement fracturés de faible perméabilité. Les fluides à haute pression sont destinés à faire évoluer les fissures et leur connectivité. Les valeurs de débit/pression auxquelles les fluides géothermiques doivent être pompés, ainsi que le calendrier de pompage pour initier la fracturation hydraulique, dépendent principalement des conditions géostatiques existantes (contraintes géostatiques, pression fluide et température initiales de l'HDR) ainsi que des propriétés des fissures de l'HDR (longueur, épaisseur, densité et distribution directionnelle initiales moyennes de fissures). Tous ces éléments, en sus de leurs effets sur la stabilité des forages, sont analysés dans cette recherche. Des modèles de fracturation, qui sont capables de suivre l'évolution des fissures dans toutes les orientations spatiales possibles, sont utilisés pour obtenir le tenseur anisotrope de perméabilité. Ces modèles sont intégrés dans un code domestique d'éléments finis qui est développé pour résoudre des problèmes aux limites thermo-poroélastiques. Pour supprimer/diminuer les oscillations qui accompagnent les solutions paraboliques et/ou hyperboliques lors de la convection forcée, plusieurs techniques de stabilisation ont dû être implémentées
The application of the Hydraulic Fracturing (HF) technology to exploit geothermal energy from Hot Dry Rocks (HDR) reservoirs is addressed. HF is achieved by extensively pumping geothermal fluids to already existing fractured HDR reservoirs of low permeability. High fluid pressures are expected to drive cracks to evolve and connect. The newly created burgeoning hydraulic conduits should supposedly enhance the permeability of the existing HDR reservoirs. The flow rate/pressure values at which geothermal fluids should be pumped, as well as the pumping schedule to initiate HF, depend primarily on the existing geostatic conditions (geostatic stresses, initial HDR pressure and temperature) as well as on HDR fracture properties (initial mean fracture length, mean fracture aperture, density and orientational distribution of fractures). While these components, in addition to their effects on borehole stability, are scrutinized in this research, focus is on the evolution during circulation processes of the fracture properties. A fracturing model that is capable of tracking fracture evolution in all possible spatial orientations is used to obtain the time course of the anisotropic permeability tensor. This evolving property is integrated into a domestic finite element code which is developed to solve thermo–poroelastic BVPs: emphasis is laid on the efficiency of the doublet flow technique where a fluid gains thermal energy by circulating through the HDR reservoir from the injection well to the production well. The spurious oscillations in the hyperbolic solutions of the approximated finite element approach that are commensal with the phenomenon of forced heat convection are healed/mitigated through several stabilization approaches

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Young, Katherine S. "Adults' responses to infant vocalisations : a neurobehavioural investigation." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:6f91f1ae-0948-4b34-b45f-ee65ae421934.

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Infant vocalisations are uniquely salient sounds in the environment. They universally attract attention and compel the listener to respond with speed and care. They provide a wealth of information to parents about their infant’s needs and affective state. There is a scientific consensus that early parenting has a profound impact on child development. In particular, the sensitivity with which parents respond to their infant’s communicative cues has been shown to affect cognitive and socio-emotional outcomes. The mechanisms underlying such sensitivity are not well understood. In this thesis, adults’ sensitivity to infant cues will be considered in terms of two components, the ‘promptness’ and ‘appropriateness’ of responses, as originally conceptualised by Bell and Ainsworth (1972). Promptness of responses is considered in terms of adults’ ability to move with speed and effort after listening to infant vocalisations. Appropriateness, on the other hand, is considered in terms of adults’ ability to differentiate between functionally significant parameters in infant vocalisations. The effect of modifiable environmental factors on the promptness and appropriateness of responses is also investigated. Finally, a focused investigation of the brain basis of responses to infant vocalisations is presented. Overall, findings demonstrated that infant vocalisations undergo privileged, specialised processing in the adult brain. After hearing an infant cry, adults with and without depression were found to move with greater coordination and effort. Adults were also found to be attuned to subtle parameters in infant cries. This sensitivity was shown to be affected by two participant-level factors, depression and previous musical training. Furthermore, this sensitivity could be enhanced through intervention, as evidenced by findings from short-term, perceptual discrimination training. The notion of privileged processing of infant vocalisations is further supported by evidence of early discrimination of infant sounds in a survival-related subcortical brain structure. Future directions for this work include directly relating current experimental measures of adults’ responses to infant cues with parental sensitivity to infant communication during dynamic interactions. Translating current findings into applied settings would require an investigation of the effects of factors such as musical and perceptual training on sensitivity to infant cues in at-risk populations, such as mothers and fathers with depression. Lastly, an increased understanding of the brain basis of adults’ sensitivity to infant cues will provide insight into our greatest challenge: parenting our young.

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Pereira, Erlick Abilio Coelho. "Deep brain surgery for pain." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:84c885f3-201a-4c6d-90ab-502194cd93ae.

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Deep brain stimulation (DBS) is a neurosurgical intervention now established for the treatment of movement disorders. For the treatment of chronic pain refractory to medical therapies, several prospective case series have been reported, but few centres worldwide have published findings from patients treated during the last decade using current standards of technology. This thesis seeks to survey the current clinical status of DBS for pain, investigate its mechanisms and their interactions with autonomic function, its clinical limitations and ablative alternatives. Presented first is a review of the current status of analgesic DBS including contemporary clinical studies. The historical background, scientific rationale, patient selection and assessment methods, surgical techniques and results are described. The clinical outcomes of DBS of the sensory thalamus and periventricular / periaqueductal grey (PAVG) matter in two centres are presented including results from several pain and quality of life measures. A series of translational investigations in human subjects receiving DBS for pain elucidating mechanisms of analgesic DBS and its effects upon autonomic function are then presented. Single photon emission tomography comparing PAVG, VP thalamus and dual target stimulation is described. Somatosensory and local field potential (LFP) recordings suggesting PAVG somatotopy are shown. ABPM results demonstrating changes with PAVG DBS are given and Portapres studies into heart rate variability changes with ventral PAVG DBS are detailed. Investigations using naloxone are then shown to hypothesise separate dorsal opioidergic and ventral parasympathetic analgesic streams in the PAVG. Finally, cingulotomy in lung cancer to relieve pain and dyspnoea results are discussed in the context of altering pain and autonomic function by functional neurosurgery. Pain and autonomic interactions and mechanisms in deep brain surgery for pain are then discussed alongside its limitations with proposals made for optimising treatment and improving outcomes.

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Aravamuthan, Bhooma Rajagopalan. "Comparing the radiological anatomy, electrophysiology, and behavioral roles of the pedunculopontine and subthalamic nuclei in the normal and parkinsonian brain." Thesis, University of Oxford, 2008. http://ora.ox.ac.uk/objects/uuid:9a735b39-c1fe-4d5f-b05f-3385f27e6e58.

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Deep brain stimulation (DBS) of the subthalamic nucleus (STN) and DBS of the pedunculopontine nucleus (PPN) have been shown to be effective surgical therapies for Parkinson’s disease (PD). To better understand the PPN and STN as DBS targets for PD, this research compares the anatomy, electrophysiology, and motor control roles of these nuclei. PPN and STN connections were examined in vivo in human subjects and in the non-human primate using probabilistic diffusion tractography. Both the PPN and STN were connected with each other and with the motor cortex (M1) and basal ganglia. After studying these anatomical connections in primates, their functional significance was further explored in an anesthetized rat model of PD. Examination of the electrophysiological relationship between the PPN and basal ganglia in the presence of slow cortical oscillatory activity suggested that excitatory input from the STN may normally modulate PPN spike timing but that inhibitory oscillatory input from the basal ganglia output nuclei has a greater effect on PPN spike timing in the parkinsonian brain. To examine transmission and modulation of oscillatory activity between these structures at higher frequencies, LFP activity was recorded from the PPN and STN in PD patients performing simple voluntary movements. Movement-related modulation of oscillatory activity predominantly occurred in the α (8-12 Hz) and low β (12-20 Hz) frequencies in the STN but in the high β (20-35 Hz) frequencies in the PPN, supporting observations from rodent studies suggesting that oscillatory activity is not directly transmitted from the STN to the PPN in PD. Finally, to better understand the roles of the STN and PPN in large-scale movement, the effects of STN and PPN DBS on gait abnormalities in PD patients were studied. DBS of the STN appeared to improve gait by optimising executive gait control while DBS of the PPN appeared to restore autonomic gait control. These results have several implications for DBS patient selection, surgical targeting, and for understanding the mechanisms underlying DBS efficacy.

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Cheng, Allen Cheuk-Seng, and allencheng@ozemail com au. "MELIOIDOSIS: EPIDEMIOLOGY, PATHOPHYSIOLOGY AND MANAGEMENT." Flinders University. Medicine, 2005. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20051121.141305.

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In under a century, melioidosis, the infection due to Burkholderia pseudomallei, has emerged from Whitmores series of glanders-like infections amongst the morphia addicts in Burma to a major cause of mortality in northeastern Thailand and northern Australia. Also endemic in other parts of south-east Asia, melioidosis may have varied presentations ranging from severe, overwhelming infection to chronic, low grade disease. Observational evidence had suggested that granulocyte colony stimulating factor (G-CSF), a naturally occurring substance produced by the body in response to infection, may have been useful in reducing the high mortality associated with the more severe forms of this infection. Other observations linked the occurrence of this disease to various environmental factors, such as contamination of drinking water and the annual rainfall. This thesis explores and attempts to quantify these associations. There are three parts to this thesis. In the first part, I reviewed the epidemiology and management of patients with melioidosis. The use of G-CSF and meropenem was associated with a fall in mortality, although other factors may have at least partially contributed to this effect. In the second part, I progressed towards a clinical trial of G-CSF. There was no other evidence supporting the use of G-CSF in severe sepsis and ethical issues precluded a trial in Darwin. There was not evidence from laboratory models of G-CSF action in melioidosis to support the use of G-CSF in patients, although there remained some doubt regarding the applicability of such models to human disease. I examined clinical methods to identify patients at high risk of death from melioidosis. A simple scoring system based on clinical and laboratory parameters was developed and externally validated. However, clinical definitions of severe sepsis appeared to be better predictors of mortality. A clinical trial based on clinical definitions was commenced in Thailand. In the final part, I explored the question of whether different strains or B. pseudomallei or different environmental conditions caused different patterns of infection. There was no evidence that strain types of this bacterium determine the pattern or severity of disease, but weather conditions appeared to influence the distribution of disease in northern Australia.

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Bock, Antje [Verfasser], Tilmann [Akademischer Betreuer] Sander-Thömmes, Klaus [Akademischer Betreuer] Obermayer, and Hermann [Akademischer Betreuer] Hinrichs. "Removal of the cardiac cycle artefact and subsequent coupling analysis between cortex and basal ganglia : simultaneous magnetoencephalographic and intracranial local field potential recordings in patients with movement disorders undergoing deep brain stimulation / Antje Bock. Gutachter: Klaus Obermayer ; Hermann Hinrichs ; Tilmann Sander-Thömmes. Betreuer: Tilmann Sander-Thömmes." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065665741/34.

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Moore, Lynn D. "Stimulating the socialization task of families within the local church reuniting the secular and the spiritual /." Theological Research Exchange Network (TREN), 1994. http://www.tren.com.

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Özcan, Orçun Orkan. "Characterization of the Purkinje cell to nuclear cell connections in mice cerebellum." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAJ085/document.

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Le cervelet permet l’apprentissage moteur et la coordination des mouvements fins. Pour ce faire, il intègre les informations sensorielles provenant de l’ensemble du corps ainsi que les commandes motrices émises par d’autres structures du système nerveux central. Les noyaux cérébelleux profonds (DCN) constituent la sortie du cervelet et intègre les informations provenant des cellules de Purkinje (PC), des fibres moussues et des fibres grimpantes. Nous avons étudié les connexions fonctionnelles entres les PC et les DNC in vivo, grâce à une stimulation optogénétique des lobules IV/V du cortex cérébelleux et à l’enregistrement multi unitaire du noyau médian. Nous avons ainsi identifié deux groupes de cellules au sein des DCN, présentant des caractéristiques propres au niveau de leur fréquence de décharge et de la forme des potentiels d’action, en accord avec la dichotomie établie par une précédente étude in vitro permettant de séparer les neurones GABAergiques des autres neurones. Nos résultats suggèrent que les PC contrôlent la sotie du cervelet d’un point de vue temporel. De plus, la ciruiterie interne des DCN conforte ce résultat de part le fait que les cellules GABAergiques ne produisent pas d’effet temporel au travers de l’inhibition locale
The cerebellum integrates motor commands with somatosensory, vestibular, visual and auditory information for motor learning and coordination functions. The deep cerebellar nuclei (DCN) generates the final output by processing inputs from Purkinje cells (PC), mossy and climbing fibers. We investigated the properties of PC connections to DCN cells using optogenetic stimulation in L7-ChR2 mice with in vivo multi electrode extracellular recordings in lobule IV/V of the cerebellar cortex and in the medial nuclei. DCN cells discharged phase locked to local field potentials in the beta, gamma and high frequency bands. We identified two groups of DCN cells with significant differences in action potential waveforms and firing rates, matching previously discriminated in vitro properties of GABAergic and non-GABAergic cells. PCs inhibited the two group of cells gradually (rate coding), however spike times were controlled for only non-GABAergic cells. Our results suggest that PC inputs temporally control the output of cerebellum and the internal DCN circuitry supports this phenomenon since GABAergic cells do not induce a temporal effect through local inhibition

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WACHSMANN, LEVY DOMINIQUE. "Immunite des muqueuses : etude de la reponse immune locale apres stimulation orale par des antigenes proteiques et polysaccharidiques de streptococcus mutans." Strasbourg 1, 1986. http://www.theses.fr/1986STR13125.

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Wachsmann, Dominique. "Immunité des muqueuses étude de la réponse immune locale après stimulation orale par des antigènes protéiques et polysaccharidiques de Streptococcus mutans /." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb376018522.

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22

Wyeth, Charles Anthony. "The role of local industrial parks in stimulating and supporting the growth and development of small, medium and micro enterprises in the Western Cape Province." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/52018.

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Thesis (MBA)--Stellenbosch University, 2000.
ENGLISH ABSTRACT: Over the past few years considerable debate has taken place regarding the role of Local lndustrial Parks (LIPs) in stimulating the growth and development of Small, Medium and Micro Enterprises (SMMEs) in South Africa. LIPs are normally established to achieve specific development objectives, namely, job creation, sector specific support, entrepreneurship/small business promotion and the provision of affordable workspace. Through interviews with centre managersof each of the LIPs located in the Western Cape Province, and the collection of other relevant information, this document appraises the performance of UPs against those criteria. The author further postulates that the term UP has evolved from a variety of other "period-names" for facilities that provide accommodation/business premises to SMMEs, and has become the current term for defining such facilities. Given the high demand for appropriately priced business premises for SMMEs, and the decision by the Cape Metropolitan Council to actively promote the establishment of UPs as a core activity in its local economic development strategy, this document recommends what services should be provided by UPs to ensure that the services offered represent value for money, and achieve the desired goals of an UP programme.
AFRIKAANSE OPSOMMING: Die afgelope paar jaar is daar hewig gedebateer oor die rol wat Plaasklike Industriële Parke (PIP) in die stimulering van ontwikkeling en groei van Klein-, Medium- en Mikro- Besighede (KMMB) in Suid Afrika speel. PIP's word normaalweg ontwikkel om spesifieke mikpunte te behaal, naamlik werksskepping, sektor-spesifieke ondersteuning, entrepreneurship/kleinbesigheids promosie en verskaffing van bekostigbare werksareas. Deur 'n proses van onderhoude met sentrum bestuurders van elk van die PIPs geleë in die Wes-Kaap Provinsie, en die versameling van ander tersaaklike inligting, meet hierdie dokument die sukses van PIP's in die lig van bogenoemde kriteria. Die outeur postuleer verder dat die term PIP 'n uitvloeisel van ander "periode-name" van fasiliteite wat werksareas en besigheids persele aan KMMB's verskaf het, is en dat dit die huidige term is om na sulke fasiliteite te verwys. Met die hoë vraag na besigheidspersele vir KMMB's teen 'n redelike tarief, en die besluit deur die Kaapse Metropolitaanse Raad om PIP's aktief te bevorder as 'n sleutel aktiwiteit in die plaaslike ekonomiese ontwikkeling strategie, meld hierdie dokument aanbevelings in terme van dienste wat deur PIP's verskaf behoort te word om te verseker dat hierdie dienste waarde vir geld verteenwoordig, en die beoogte mikpunte van die PIP bereik.

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Hansson, Kristina. "Den förvandlade kommunen : Ekonomisk och social tillväxt i Örnsköldsvik 1997-2007." Thesis, Södertörn University College, School of Social Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-1725.

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The transformed municipality – Economic and social growth in Örnsköldsvik 1997-2007

Author: Kristina Hansson

This thesis focuses on the economic and social growth in the municipality of Örnsköldsvik. It is a single case study and the municipality is studied through economic theories concerning regional growth in the period of 1997-2007. The aim is to analyse whether these theories, such as Åke E. Anderssons and Ulf Strömquists K-society, and other more or less microeconomic assumptions, also are applicable in smaller local contexts. The aim is fulfilled through a mix of text analyses, interviews with leading politicians, civil servants and executives, together with definitions of several quantitative characteristics of economic and social growth. Alternative theories in the thesis concern identity, trust and social capital. Seven independent variables are studied: infrastructure, economic and commercial policy, steering by goals, streamlining, public purchase, marketing and higher education. The results show that while Örnsköldsvik has experienced an extraordinary economic growth, the social growth lags behind. The conclusion is therefore, that economic theories are not enough to explain both economic and social growth at the municipality level. This strengthens the assumption that the explanation to municipal growth in reality lays in the local forces.

Keywords: structural change, local growth, municipal taxes, public- private cooperation, state-subsidized stimulating measures

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Manullang, Sahat Manondang. "The development of SMEs in Bukit Barisan High Land Area to create an agricultural center by using a solid cooperation between local governments, enterprises, and farmers : an application of competitive intelligence for stimulating the growth." Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00468693.

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The research has been conducted in Bukit Barisan High Land zone consists of eight regencies located in the northern part of North Sumatra province, Indonesia. It is found that the zone is entrapped in a high poverty rate and a high unemployment level. The regions main employment sector is agriculture, where more than 50 percent of the total workforce engages in the sector. The main challenging of the regions is a very low productivity. This is due to lack of management practices and capacities in term of tools inputs, and knowledge now-how. Moreover, the lack of information and coordination between the actors of the economy i.e. farmers-local governments-enterprises-and universities in the regions has dragged away the value added products and inherited in high fluctuation of the commodities in term of prices and qualities. Accordingly a new cooperation needs to be made between all the actors of the economy in the regions. As information has a vital role in the development of the regions, this sector hence ought to be diffused in an appropriate way. This information center then called as a Competitive Intelligence (CI) Center, which is importantly formed in each region in Bukit Barisan High Land zone. The CI center will ensure the formation of the sound development programs to be applied in the regions in order to achieve a desirable growth within the regions and within the country as a whole. The program of CI center is emphasized on enhancing the potentials of each region and overcome its problems and challenging. In this thesis, Bukit Barisan High Land which consists of 8 regions is categorized as one zone regarding similarity in its topography, climate, type of soil, social condition of the society, its potentials and problems. The development of the region then suggested by the creation of the Small and Medium Enterprises close to the region to ensure the achievement of value chain between suppliers and producers in this case Farmers and enterprises. This value chain can only be achieved by a solid collaboration by all economic actors. Based on the findings, it is suggested that the most prospective commodities need to be intensified are coffee and corn. Corn is perceived as one of a prospective export regarding a continuous increase demand for the commodity globally, whereas coffee is a permanent export commodity where the decreasing supply by Vietnam has contributed to more opportunity to Indonesia. In order to provide some vision to investors, the feasibility studies of the plantation and production of two commodities will be presented at the last part of the thesis

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Zhao, Bo. "Local mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), macrophage colony-stimulating factor (MCSF-1), and its receptor, c-fms, on rabbit heart valves in the early phase after atrioventricular valve surgery and Staphylococcus aureus bacteremia." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972046437.

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Pan, Po-Jung, and 潘柏榮. "Protective Effects of Preconditioned Local Somatothermal Stimulation on Acupoint BL 37 against." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/06987983539206187394.

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碩士
國立陽明大學
傳統醫藥學研究所
96
The aim of this study was to investigate whether preconditioned local somatotheral stimulation (LSTS) protects the muscle and nerve against ischemia -reperfusion (I/R) injuries. Male rats were randomly assigned to normal, preconditioned LSTS only and I/R injured groups with or without LSTS preconditioning. I/R injuries of lower limb were induced by rubber band wrapping, followed by measurement of the gait function, nerve conduction, as well as the muscle pathology, serum enzymatic activity and the expression of heat shock protein 70 (HSP-70) in the gastrocnemius muscles. The results showed that there was no significant change of neuromuscular function between LSTS (-) and LSTS (+) groups on the 1st day after I/R injury. In contrast, there were significantly improved gait functions such as gait stride length, compound motor action potential and serum creatine phosphokinase MM isoenzyme on the 8th day after 1 or 2 doses preconditioned LSTS and subsequent I/R injury. Western blot analysis disclosed no significant change of HSP-70 expression in the muscle of I/R injured limbs between LSTS (-) and LSTS (+) groups. We conclude that the preconditioned LSTS is a safe modality that improves the neuromuscular plasticity against I/R injured limbs, which provides a new strategy for I/R injury in clinical application, such as intraoperative use of tourniquets.

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Liu, Ta-Wei, and 劉達偉. "Synchronization Study of Regional Local Field Potential in Rat after Dopamine Receptor Stimulation." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/43705396281058367763.

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碩士
國立交通大學
電控工程研究所
99
Neural oscillation represent the neural activity in nervous system, by recording neural oscillation connectivity and interactions within brain networks could be investigated in an effective measure. A wealth of research have suggested that electrophysiological signals in brain networks would interact with each other, and synchronization between distinct areas has been implied the mechanism for brain interaction. With disease influence or external stimulation, the neural oscillation induce linear and non-linear interaction. However, the neural oscillation interaction originated from different brain areas need more investigation to realize the operation in brain networks. Therefore, the aim of this thesis attempts to explore the non-linear interaction with cross-frequency coupling in brain network during the stimulation of dopamine receptors. We record local field potential (LFP) in rats from striatum and motor cortex, giving stimulation on dopamine D2 receptors with dopamine receptor agonist and antagonist. Analysis with coherence and bispectral analysis discuss LFP synchronization between striatum and motor cortex that changes with drug stimulations, discussing the interaction between brain areas with and without drug stimulations. Results demonstrate that oscillations between striatum and motor cortex at delta and theta bands appear significant inverse synchrony changes in identical frequency band with different stimulations. Meanwhile, different stimulations induce cross-frequency bands synchronized or interferential synchrony fluctuations in brain with direction specificity, providing a further investigation and a special point of view in intracerebral neural oscillations interaction in neural network when dopamine receptors stimulated by drugs.

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Chen, Ying-Ming, and 陳應明. "Effect of local somatothermal stimulation at acupoints on renal micro-perfusion in rat." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/63338716096505978599.

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碩士
國立陽明大學
傳統醫藥學研究所
90
ABSTRACT Acumoxa (acupuncture and moxibustion) is a very important technique in the Chinese traditional medicine (T.C.M.). During past years, there were many studies about the mechanism of acupuncture were published. However, the studies about the moxibustion were rare. According to the concept of TCM, there are specific relationships between the internal organs and their corresponding meridians. We had successfully established the animal model to explore the modulator effect of local somato-thermal stimulation (LSTS) on the sphincter of Oddi in rat during past years. In addition, we had found that acupuncture on the acupoint PC 6 provide the protection effect against coronary artery ischemia/reperfusion injury. Furthermore, we are going to explore whether the effect of above study being exists in other meridians and its corresponding organs or not. Besides, we had found many of above effect works via increase the expression of nitric oxide. Reviewing literatures, we knew that there are many renal diseases were related to the decreased expression of nitric oxide. This is our aim to explore whether the disease mentioned above can be treated via increasing the expression of nitric oxide by means of LSTS or not. We assigned the LASER Doppler flowmetry in rat to establish the animal model to explore the effect of LSTS on renal micro-perfusion and the corresponding mechanism. Our finding is that the effect of LSTS on renal micro-perfusion is acupionts or meridian specific. The effect mentioned above can be blocked by treatment with L-NAME and can be reversed again by L-Arginine. The effect of LSTS on expression of heat shock protein 70 in kidneys is doses-related. Furthermore, we found the LSTS provide protection against ischemia/reperfusion injury on kidneys. Our conclusion is that the renal cortical micro-circulation will be effected after applying LSTS on specific acupoints. The mechanism is probably related to the expression of nitric oxide.

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Tung, Hwa-Hsung, and 童華雄. "Induction of Heat Shock Protein70 at Acupoints and Corresponding Organs by Local Somatothermal Stimulation." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/21796536319477774063.

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碩士
國立陽明大學
傳統醫藥學研究所
88
Heat-shock proteins ( HSPs ), a group of molecular chaperons, are expressed when host is homogeneously exposed to heat stress environment. It is our aim to investigate whether the local somatothermal stimulation ( LSTS ), a component of moxibustion in Traditional Chinese Medicine, induces the expression Hsps on the somatic stimulation sites ( acupoints ) and the corresponding organs, such as liver and heart. Monoclonal antibody against HSP70 and RT-PCR were used to study the gene expression of HSP at protein and transcriptional levels in Spraque-Dawley rats ( 250-300 gm ). LSTS was brought about by application of a heating rod 0.5 cm above and to the acupoints Neiquan ( PC6 ) and Qimen ( Liv14 ). The expression of HSP70 family was assessed in the corresponding organs, heart and liver, respectively. In the mean time, dose-dependent response and time course for the expression of HSP70 was also studied on the LSTS stimulation site. The results showed that HSP70 was expressed in the underlying muscle when LSTS was applied to the destined skin area as compared to that of the contralateral muscle. When LSTS was applied to left Neiquan ( PC6 ), the expression of HSP70 in the corresponding organ ( heart ) was higher than that without LSTS. Whereas LSTS was applied to right Qimen ( Liv14 ), the expression of HSP70 in the liver was higher than that without LSTS. Surprisingly, no protective effect was noticed in the livers from ischemia reperfusion injury when rats were primed with 2 doses of LSTS. We conclude that local application of heat stress on somatic acupoints induces an up-regulation of HSP gene expression on regional muscles and the corresponding internal organs. This might provide scientific evidence for Traditional Chinese medicine in the treatment of human diseases.

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Ting-YiHuang and 黃庭儀. "Radial Pulse Detection and Analysis of Local Cold Stimulation Test by Multiple Dimension Pulse Mapping Method." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/cgdw82.

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碩士
國立成功大學
電機工程學系
102
Arterial stiffness, a common disorder affecting nearly 30% of population in Taiwan, is an early marker of cardiovascular diseases. Since prevention is better than cure, a non-invasive approach for early detection has come into its own. One of the familiar ways to investigate arterial stiffness risk factors is PWA, measuring radial pulse waves with single-point sensors and widely used in palpation of TCM. Radial pulse waves consist of multiple waves indicating health status; however, the resolution of single-point PWA is different from human fingers. Accordingly, this study utilized multiple-point BSPDI to record radial pulse waves, and then constructed multiple dimension pulse mapping with numerical analysis. 30 healthy subjects, 22.10±3.52 years old, BMI 20.30±1.54, and blood pressure 111.30±4.96/73.57±3.31mmHg, were studied by given local cold stimulation test at “Chi” on left hand to simulate arterial stiffness and by observing radial pulse waves during Base, Cold Stimulation, and Recovery Stage, respectively. According to results, on PWA, significantly higher (P〈0.001) AI and H3/H1 occurred after local cold stimulation test making radial artery stiffer. On 3DPM analysis, major axes were significantly longer as contour values were from 0.5 to 0.8(P〈0.001). On Dynamic 2DPM analysis, major axes were significantly longer (P〈0.001 as contour values were from 0.5 to 0.8) and so were time axes(P〈0.001 as contour values were 0.5 and 0.6; P〈0.01 as contour values were 0.7; P〈0.05 as contour values were 0.8). This implied that local cold stimulation test induced lower arterial compliance associated with taut pulse and provided physicians with a novel way to take care of patients’ health status.

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Chen, Chun-Ling, and 陳俊麟. "Studies of Acupoints Specificity on the Motility of Sphincter of Oddi by Local Somatothermal Stimulation in Rabbits." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/54789324562009030109.

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碩士
國立陽明大學
傳統醫藥學研究所
88
Acupmoxa (Acupuncture and moxibustion) is a popularly applied technique in ancient China and plays an important role in therapeutics of traditional Chinese medicine. There were a lot of studies focuses on pain-relief mechanism by acupuncture in past 3 decades years. Little is known about how and why the visceral function modulated through moxibustion. It has been postulated that comparative acupoints specificity could be observed when visceral function are affected via providing stimulation on the skin. It is our purpose to test the hypothesis of comparative acupoints specificity and to demonstrate that local somatothermal stimulation (LSTS) affects rabbits’ sphincter of Oddi （SO）through VIP-related mechanism. The activity of the SO in anesthetized rabbits was measured by use of continuously perfused open-tip manometric methods. LSTS was achieved by applying an electroheating rod 0.5 cm away from the skin.The response were further manipulated by pretreating the rabbits with anti-VIP serum. The results showed that there are less modulation effects on nonpoint than acupoint, and the effects of LSTS on the L’t Riyue(GB24) is different from that on the right one, especially at the attenuation effect of phasic contraction pressure. Similar effects was observed between Qiuxu (GB40) and Yanglingquan(GB34), but no significant effects were observed when LSTS was applied on acupoint of kidney meridian Taixi (K3). There are synergic modulating effect can be observed when LSTS was applied on bilateral Riyue (GB24) or R’t Riyue (GB24) and Yanglingquan(GB34). The local heat—induced SO relaxation is not inhibited by pretreatment with Atropin, pentolamine and propanolol, but is significantly blocked by pretreatment with Atropin, pentolamine , propanolol and anti-VIP serum . We conclude that comparative acupoints specificity can be observed. In addition, VIP-related mechanism might be involved in the modulation of SO motility by LSTS. These results might provide important information for clinical treatment..

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32

Cardoso, Inês Catarina Prego. "Exploring the role of subthalamic nucleus local field potentials recordings in Parkinson´s disease deep brain stimulation." Master's thesis, 2021. http://hdl.handle.net/10451/52188.

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Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2021
Contextualização: Os Local Field Potentials (LFPs) permitem a medição da atividade neuroelétrica do núcleo subtalâmico (NST) e constituem promissores biomarcadores de parkinsonismo na doença de Parkinson (DP). Atividades voluntárias podem interferir com o grau de parkinsonismo. O registo de LFPs constitui uma oportunidade para investigar a influência de tarefas voluntárias sobre a atividade neuroelétrica do NST e sobre o funcionamento de sistemas de estimulação cerebral profunda (DBS) em circuito fechado. Objetivos: Investigar a interferência de atividades voluntárias no registo dos LFPs do NST. Objetivos secundários: investigar a relação entre manifestações clínicas e terapêutica instituída e o registo de LFPs do NST. Metodologia: Estudo n=1 transversal e prospetivo, com múltiplos cruzamentos de 3 tarefas (fala, movimentos das mãos e marcha), sob de 4 condições, consoante estimulação (STIM)/medicação (MED), ao 1º e 6 meses DBS, em doente implantado com elétrodos com capacidade de registo de LFPs. A avaliação clínica foi realizada utilizando a MDS-UPDRS III. As flutuações motoras e discinésias foram registadas num diário de Hauser. Realizou-se a análise descritiva dos resultados. Resultados: Identificou-se a interferência de atividades voluntárias sobre os registos de LFPs, preferencialmente em STIM OFF. A fala associou-se consistentemente à diminuição da intensidade da banda beta; os movimentos das mãos e marcha à diminuição de beta e a marcha ao aumento de gama. No período STIM OFF/MED ON, identificou-se uma diminuição da intensidade de low beta, concomitante à melhoria da MDS-UPDRS III relativamente a MED OFF. Conclusões: A atividade voluntária interfere no registo de LFPs do NST em STIM OFF. A ausência de interferência significativa em STIM ON não apoia a sua relevância em sistemas DBS em circuito fechado. O nosso estudo contribui para a investigação na fisiopatologia da DP e em DBS e suporta a realização de futuros estudos nesta área.
Background: Local Field Potentials (LFPs) allow the measurement of subthalamic nucleus´s (STN) neuroelectrical cerebral activity and constitute promising biomarkers of parkinsonism in Parkinson’s disease (PD). Voluntary activities may interfere with the parkinsonism level. Recording LFPs of STN constitutes an opportunity to investigate the influence of voluntary tasks on STN´s neuroelectric activity and on Deep Brain Stimulation (DBS) systems in closed loop. Objectives: Investigate the interference of voluntary movement in the LFPs recordings. Secondary objectives: Investigate the relationship between clinical manifestations and instituted therapeutics and the NST´s LFPs recordings. Methods: Cross-sectional and Prospective Study n=1, with multiple crossings of 3 tasks (speech, hand movements and gait) under 4 conditions, depending on stimulation (STIM)/ medication (MED), at first and sixth month after DBS, in a patient implanted with LFP´s recording capacity electrodes. The clinical evaluation was made through MDS-UPDRS III. Motor fluctuations and dyskinesias were registered in an Hauser´s diary. It was made a descriptive analysis of the results. Results: It was identified the interference of voluntary activities in the LFP´s recordings, mainly under STIM OFF. Speech was consistently associated with a beta band intensity’s decrease; hand movements and gait with beta band intensity’s decrease and gait also with gama band intensity´s increase. Under STIM OFF/MED ON, the beta band intensity’s decrease was simultaneously associated with an improvement in MDS-UPDRS III comparing with MED OFF. Conclusions: Voluntary activity interferes in NST´s LFPs recordings under STIM OFF. The absence of this interference under STIM ON doesn´t support its relevance in closed loop DBS systems. Our study contributed for the research on PD´s pathophysiology and DBS and supports the relevance of new studies in this field.

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Salavatian, Siamak. "Analysis of intrinsic cardiac neuron activity in relation to neurogenic atrial fibrillation and vagal stimulation." Thèse, 2015. http://hdl.handle.net/1866/13549.

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La fibrillation auriculaire est le trouble du rythme le plus fréquent chez l'homme. Elle conduit souvent à de graves complications telles que l'insuffisance cardiaque et les accidents vasculaires cérébraux. Un mécanisme neurogène de la fibrillation auriculaire mis en évidence. L'induction de tachyarythmie par stimulation du nerf médiastinal a été proposée comme modèle pour étudier la fibrillation auriculaire neurogène. Dans cette thèse, nous avons étudié l'activité des neurones cardiaques intrinsèques et leurs interactions à l'intérieur des plexus ganglionnaires de l'oreillette droite dans un modèle canin de la fibrillation auriculaire neurogène. Ces activités ont été enregistrées par un réseau multicanal de microélectrodes empalé dans le plexus ganglionnaire de l'oreillette droite. L'enregistrement de l'activité neuronale a été effectué continument sur une période de près de 4 heures comprenant différentes interventions vasculaires (occlusion de l'aorte, de la veine cave inférieure, puis de l'artère coronaire descendante antérieure gauche), des stimuli mécaniques (toucher de l'oreillette ou du ventricule) et électriques (stimulation du nerf vague ou des ganglions stellaires) ainsi que des épisodes induits de fibrillation auriculaire. L'identification et la classification neuronale ont été effectuées en utilisant l'analyse en composantes principales et le partitionnement de données (cluster analysis) dans le logiciel Spike2. Une nouvelle méthode basée sur l'analyse en composante principale est proposée pour annuler l'activité auriculaire superposée sur le signal neuronal et ainsi augmenter la précision de l'identification de la réponse neuronale et de la classification. En se basant sur la réponse neuronale, nous avons défini des sous-types de neurones (afférent, efférent et les neurones des circuits locaux). Leur activité liée à différents facteurs de stress nous ont permis de fournir une description plus détaillée du système nerveux cardiaque intrinsèque. La majorité des neurones enregistrés ont réagi à des épisodes de fibrillation auriculaire en devenant plus actifs. Cette hyperactivité des neurones cardiaques intrinsèques suggère que le contrôle de cette activité pourrait aider à prévenir la fibrillation auriculaire neurogène. Puisque la stimulation à basse intensité du nerf vague affaiblit l'activité neuronale cardiaque intrinsèque (en particulier pour les neurones afférents et convergents des circuits locaux), nous avons examiné si cette intervention pouvait être appliquée comme thérapie pour la fibrillation auriculaire. Nos résultats montrent que la stimulation du nerf vague droit a été en mesure d'atténuer la fibrillation auriculaire dans 12 des 16 cas malgré un effet pro-arythmique défavorable dans 1 des 16 cas. L'action protective a diminué au fil du temps et est devenue inefficace après ~ 40 minutes après 3 minutes de stimulation du nerf vague.
Atrial fibrillation is the most frequent sustained rhythm disorder in humans and often leads to severe complications such as heart failure and stroke. A neurogenic mechanism of atrial fibrillation has been hypothesized. Tachyarrhythmia induction by mediastinal nerve stimulation has been proposed as a model to study neurogenic atrial fibrillation. In this thesis, we studied the activity of intrinsic cardiac neurons and their interactions inside the right atrium ganglionated plexus in a canine model of neurogenic atrial fibrillation. These activities were recorded by a multichannel microelectrode array that was paled into the right atrium ganglionated plexus. The recording was done for up to 4 hours and it covered the neuronal activity during different interventions such as vascular (aorta occlusion, inferior vena cava occlusion, left anterior descending coronary artery occlusion), mechanical (touching atrium and ventricle) and electrical (stimulating of vagus nerve or stellate ganglion) stimuli as well as atrial fibrillation induction. Neuronal identification and classification were done using the principal component analysis and cluster on measurements analysis in Spike2 software. New method based on principal component analysis was proposed to cancel superimposed atrial activity on neuronal signal to increase the accuracy of the neuronal response identification and classification. Based on the neuronal response, we defined subtypes of neurons (afferent, efferent and local circuit neurons) and their related activity to different stressors which provided a more detailed description of the intrinsic cardiac nervous system. The majority of recorded neurons reacted to episodes of atrial fibrillation by becoming more active. This hyperactivity of intrinsic cardiac neurons during atrial fibrillation suggested that controlling that activity might help preventing neurogenic atrial fibrillation. Since low-level vagus nerve stimulation obtunds the intrinsic cardiac neuronal activity (especially for afferent and convergent local circuit neurons), we investigated whether this intervention could be applied as a therapy for atrial fibrillation. Our results showed that right vagus nerve stimulation was able to mitigate atrial fibrillation in 12 of 16 cases and showed an adverse pro-arrhythmic effect in 1 of 16 cases. The protective action however decreased over time and became ineffective after ~40 minutes for 3 minutes vagus nerve stimulation.

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34

Lin, Yu-Yen, and 林佑彥. "Changes of Synaptic Plasticity Gene Expression by Electroacpuncture (EA) and Local Somatothermal Stimulation (LSTS) in Mice Model of Streptozotocin-Induced Diabetes Mellitus." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/6xnv74.

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Hsu, Cheng-Fong, and 徐晨峰. "Effects of Local Somatothermal Stimulation on Free Radical Formation in the Muscle underlying Acupoint PC 6 and the Corresponding Organ (Heart) in Rats." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/52mgcq.

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碩士
國立陽明大學
傳統醫藥學研究所
97
Local somatothermal stimulation (LSTS) was demonstrated to increase the expression of myocardial heat shock protein 70 (Hsp70) and protected rat hearts against ischemia-reperfusion injury. However, the exact mechanisms of how LSTS works remains unknown. The aim of this study was to test the hypothesis that LSTS at PC 6 induced free radicals formation in the muscle beneath acupoint and subsequently induced Hsp70 expression in the heart. LSTS was applied 0.5 cm above and onto acupoint Fujie (SP 14) and Neiguan (PC 6), respectively. Under adequate anesthesia, male Sprague–Dawley rat, were treated with LSTS for 1 dose. Following time intervals of 0 min (no treatment),5-, 15-, 30- and 60- min, respectively, reactive oxygen species (ROS) were measured by 2′,7′-dichlorofluorescin diacetate (DCFH-DA) fluorometric assay. Nitrate and nitrite (nitric oxide (NO) end products), malondialdehyde (MDA) , cyclic guanosine monophosphate (cGMP) and free radical scavengers were measured by commercial available kits. Western blot analysis for Hsp70 and Nuclear factor erythroid 2–related factor 2 (Nrf2) in the muscle and the heart were also analyzed; the parameters such as serum creatine kinase-MB isoenzyme (CK-MB) and cardiac tropnin I (cTnI) were measured to evaluate the myocardial injury. The results showed that the generation of ROS, NO end products (nitrate and nitrite) and MDA in 5 min-, the consumption of superoxide dismutase (SOD) in 5 min-, and the consumption of catalase (CAT) and glutathione (GSH) in 15 min- after the application of LSTS suggested that there were free radicals formation in the muscle beneath the acupoint area. The LSTS-induced Hsp70 expression in the muscle were partially blocked by L-NAME treatment. Besides, the formation of ROS, MDA, cGMP and Nrf2 in 5 min- , the increase of serum CK-MB and cTnI in 15 min- and subsequently the generation of SOD in 30 min- suggested that there were free radicals formation in the heart after LSTS treatment on left PC 6. Finally, There were also ROS, NO end products (nitrate and nitrite) and Nrf2 expression in 5 min- after LSTS were noticed in the muscle beneath acupoint PC 6. We concluded that LSTS induced free radicals formation in the muscle beneath the acupoint PC 6 and, the corresponding organ–heart, which might explain the possible mechanisms of LSTS-induced myocardial protection in rats.

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Gertrudes, Ricardo António Costa. "Anterior nucleus of thalamus deep brain stimulation : a clinical-based analysis of the ideal target in medically refractory epilepsy." Master's thesis, 2020. http://hdl.handle.net/10451/48987.

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Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2020
Objectivo: A Estimulação Cerebral Profunda do núcleo anterior do tálamo (ANT-DBS) é um procedimento aprovado para a epilepsia medicamente refractária. No entanto, nenhuma localização preferida dentro do ANT foi inequivocamente descoberta. Neste estudo, nós investigámos a relação entre as coordenadas estereotáxicas dos contactos estimulados e a melhoria clínica, de modo a definir o alvo ideal para ANT-DBS. Métodos: Um total de 19 pares de contactos foram utilizados em 14 pacientes, com um follow-up mínimo de 11 meses contínuos de estimulação. Cada par de contactos foi classificado como respondedor (≥50% redução de crises epilépticas e ausência de efeitos adversos intoleráveis) ou não respondedor. As coordenadas de cada contacto foram obtidas no espaço do Montreal Neurological Institute 152, com a utilização de ferramentas de normalização avançadas e registro simultâneo de imagens pré e pósoperatória de TC e RMN, no Lead-DBS. Resultados: Um local altamente encorajador dentro do ANT (HELIA, a partir do original em Inglês) foi delimitado no espaço MNI, correspondendo a uma área na metade anterior e inferior do núcleo anteroventral (AV), medialmente ao ponto terminal do tracto mamilo-talâmico (junção ANT-mtt). Foi obtida uma diferença estatisticamente significativa entre respondedores e não respondedores, em termos do número de localizações dentro do HELIA. Conclusões: Uma relação entre a localização dos contactos estimulados e o estado de resposta foi observada na epilepsia medicamente refractária. O planeamento direto do alvo dentro do HELIA pode ajudar a ultrapassar variações anatómicas e potencialmente aumentar o benefício clínico.
Objective: Deep Brain Stimulation of the anterior nucleus of thalamus (ANT-DBS) is an approved procedure for medically refractory epilepsy (MRE). However, no preferred location inside ANT has been unequivocally discovered. In this study, we investigated the relationship between stereotactical coordinates of stimulated contacts and clinical improvement, in order to define the ideal target for ANT-DBS. Methods: A total of 19 contacts’ pairs, with a minimum follow-up of 11 continuous months of stimulation, were used in 14 patients. Each contacts’ pair was either classified as a responder (≥50% seizure reduction and absence of intolerable adverse effects) or non-responder. Individual contact’s coordinates were obtained in Montreal Neurological Institute (MNI) 152 space, with the utilization of advanced normalization tools and co-registration of pre and postoperative MRI and CT images in Lead-DBS. Results: A highly encouraging location inside ANT (HELIA) was delimited in MNI space, corresponding to an area in the anterior and inferior half of the anteroventral nucleus (AV), medially to the endpoint of the mammillothalamic tract (ANT-mtt junction). Statistically significant difference was attained between responders and nonresponders, in terms of the number of locations inside HELIA. Conclusions: A relationship between stimulated contacts’ locations and responder status was observed in medically refractory epilepsy. Direct targeting of locations inside HELIA may help surpass anatomical variations and possibly augment clinical benefit.

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Toppi, Gary R. (Gary Robert) 1966. "The use of cell demodulated electronic targeted anesthesia to control dental operative pain in pediatric patients." Thesis, 1999. http://hdl.handle.net/1805/4144.

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Indiana University-Purdue University Indianapolis (IUPUI)
The pain-controlling effects of a recently introduced electronic dental anesthesia device (CEDETA) were compared with those of local anesthesia in this study. Procedures performed involved full-coverage stainless steel crowns on maxillary primary molars, some of which required indirect pulp therapy and pulpotomies. A total of 55 children, aged 6 years to 10 1/2 years, were randomly selected to have treatment done with CEDETA or local anesthetic. Eight of these patients were treated with both CEDETA and local anesthetic at different appointments. At various times during each procedure, the patient and operator rated the patient's level of discomfort using a 6-point Visual Analog Scale. For each of the five evaluation steps, no significant differences existed in discomfort ratings between the CEDETA and local anesthetic methods for the group of eight patients or for the entire group. Operator ratings of patient discomfort did not vary significantly between the two methods of anesthesia for each of the evaluation steps, except at the step of maximum output or after injection, when the CEDETA group as a whole had significantly lower operator-rated pain. In general, patients tended to rate their perceptions of pain higher than those of the operator. Although the operator and patients in this study found CEDETA to be as effective as local anesthetic for controlling dental operative pain, a number of factors must be considered when deciding to use this type of electronic dental anesthesia. A substantial monetary investment is required to purchase the CEDETA device and the disposable electrodes and batteries to power the unit. There is an increased operating expense for each procedure done when using CEDETA, because of the additional time needed for the operator, staff, and patients to become familiar with the use of the device. Additional setup and break-down time is also needed when using CEDETA as opposed to local anesthetic.

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Sundaram, Arun N. E. "Saccade Related Gamma Potentials Recorded in Human Subthalamic Nucleus, Globus Pallidus Interna and Ventrointermediate Nucleus of the Thalamus." Thesis, 2012. http://hdl.handle.net/1807/33702.

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Gamma oscillations of local field potentials (LFP) in the basal ganglia and thalamus had not been studied during saccades. Eleven patients were studied during deep brain stimulation (DBS); 6 were in the subthalamic nucleus (STN); 3 in the globus pallidus interna (GPi); and 2 in the thalamic ventralis intermedius nucleus (Vim). Patients performed horizontal saccades to visual targets while LFPs from DBS electrodes, scalp electroencephalogram (EEG), and electrooculogram (EOG) were recorded. Wavelet spectrograms were generated and saccade onset and event-related gamma synchronizations (ERS) were compared to baseline without eye motion. ERS were recorded at and after saccade onset in the STN, GPi and Vim, EEGs and EOGs; but were absent during target light illumination without saccades. ERS were symmetric in all DBS contacts and appeared identical in DBS LFPs, frontal EEGs and EOGs. These findings indicate their origin from extraocular muscle spike potentials rather than brain neural activity.

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Παπαμιχάλης, Βασίλειος. "Χρήση του μοντέλου Izhikevich για προσομοίωση της νευροφυσιολογικής λειτουργίας του υποθαλαμικού πυρήνα με βάση δυναμικά τοπικού πεδίου." Thesis, 2010. http://nemertes.lis.upatras.gr/jspui/handle/10889/3955.

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Στην παρούσα εργασία μελετάμε τη μοντελοποίηση του υποθαλαμικού πυρήνα των βασικών γαγγλίων με χρήση του μαθηματικού νευρωνικού μοντέλου Izhikevich. Βάση της μελέτης μας αποτελούν μικροηλεκτροδιακές καταγραφές, που έχουν ληφθεί κατά τη διάρκεια νευροχειρουργικών επεμβάσεων εν τω βάθει εγκεφαλικής διέγερσης, για τη συμπτωματική θεραπεία της νόσου Πάρκινσον. Θα ξεκινήσουμε με μια εισαγωγή στην φυσιολογία του νευρικού κυττάρου και στην ανατομία των βασικών γαγγλίων. Θα αναλύσουμε τα βασικά ποιοτικά μοντέλα που ερμηνεύουν τη συμμετοχή των τελευταίων σε κινητικές διεργασίες, αλλά και την εμπλοκή τους στη νόσο Πάρκινσον. Μετά από μια σύντομη αναφορά στη μέθοδο της εν τω βάθει διέγερσης και στις μικροηλεκτροδιακές καταγραφές, θα εστιάσουμε στα δυναμικά τοπικού πεδίου και στη νευροφυσιολογική σημασία τους. Συνεχίζοντας, θα κάνουμε μια περιεκτική ανασκόπηση των βασικότερων μαθηματικών μοντέλων νευρώνων και ύστερα θα επικεντρωθούμε στον υποθαλαμικό πυρήνα, περιγράφοντας δύο πρόσφατα μοντέλα που έχουν κατασκευαστεί για την προσομοίωση των νευρώνων αυτού. Έπειτα, θα περάσουμε στην περιγραφή του μοντέλου Izhikevich και στην τροποποίησή του για την αναπαραγωγή των χαρακτηριστικών του νευρώνα του υποθαλαμικού πυρήνα. Κατόπιν, θα αναλύσουμε τη μεθοδολογία που ακολουθήσαμε στην παρούσα υλοποίηση και τις βασικές θεωρήσεις της μοντελοποίησης μας. Θα ολοκληρώσουμε με την παρουσίαση των αποτελεσμάτων, το σχολιασμό αυτών και τις ιδέες για μελλοντική επέκταση της μεθόδου μας.
The main objective of this MSc thesis is the study of subthalamic nucleus, by using the Izhikevich neuron model. Microelectrode recordings, taken during deep brain stimulation operations for Parkinson’s disease, have been used for that purpose. In chapters 1-2, there is an introduction to the physiology of the neuron and the basal ganglia anatomy. In the two following chapters, we are analyzing the basic qualitative models that describe the involvement of the basal ganglia in movements and the pathophysiology of Parkinson’s disease. We are briefly discussing the method of deep brain stimulation, microelectrode recordings processing and the extraction of local field potentials. In chapter 5, the basic mathematical neuron models are discussed. We are focusing on the subthalamic nucleus and we are describing two recently developed mathematical models of the subthalamic neuron. In chapter 6, we are outlining Izhikevich neuron model and its modification in order to describe the subthalamic neuron. In addition, we are analyzing the methodology developed for the implementation of the modeling process and our basic considerations. In chapter 7, the results of the simulation are presented and discussed, so that our conclusions provide ideas for further research.

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Mutapanduwa, Simbarashe Morgan. "Assessment of the contributions of air transportation in stimulating local economic development in Vhembe District." Diss., 2016. http://hdl.handle.net/11602/376.

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Schill, Tillmann Oldwig. "Lokale Stimulation des pulmonalen Immunsystems mit dem TLR2/6-Agonisten MALP-2 und deren Auswirkung auf pulmonale Melanommetastasierung im Maus-Modell." Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0022-5F08-8.

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Eine Melanomerkrankung im metastasierten Stadium ist heute noch eine nicht heilbare und in den meisten Fällen tödlich verlaufende Erkrankung. Über 50% der Patienten mit metastasierendem malignen Melanom entwickeln Lungenmetastasen. Nach dem Auftreten von Lungenmetastasen beträgt die durchschnittliche Überlebenszeit noch 7,3 Monate. Demnach ist die Entwicklung von Therapiestrategien notwendig, um das Fortschreiten von Tumormetastasen oder sogar deren Entstehung zu verhindern. Die lokale Stimulation der angeborenen Immunabwehr durch Behandlung mit Toll-like-Rezeptor-Agonisten käme hierfür in Frage. Inhalative Behandlungen mit Immunmodulatoren, wie sie für IL-2 beschrieben wurden, könnten insbesondere für die Behandlung pulmonaler Metastasen genutzt werden. In der vorliegenden Arbeit wurde das pulmonale angeborene Immunsystem im Mausmodell durch den TLR2/6-Agonisten MALP-2 stimuliert und die Auswirkung dieser Immunstimulation auf experimentell induzierte pulmonale Melanommetastasen untersucht. Intratracheale Instillationen von 0,5 µg MALP-2 führten zu starker Einwanderung neutrophiler Granulozyten (6-fach) und Makrophagen (3,4-fach) in die Lunge von C57/BL6-Mäusen. Innerhalb von 24 h war das Maximum der Immunzelleinwanderung erreicht. Der Leukozyteneinstrom fiel dann innerhalb von 72 h wieder auf das Ursprungsniveau zurück. Weitere Untersuchungen konnten zeigen, dass MALP-2 auch zu einer deutlichen Steigerung der Expression von VCAM-1 in pulmonalen Blutgefäßen führt. In vitro Experimente zeigten, dass dieses Adhäsionsmolekül die Bindung von B16-F10-Melanomzellen vermitteln kann. Außerdem führte die MALP-2-Behandlung weder in vitro noch in vivo zu einer signifikanten Steigerung der Fähigkeit von Immunzellen, B16-F10-Melanomzellen zu lysieren. So konnte, im Gegensatz zu Rückschlüssen aus früheren Publikationen, trotz der ausgeprägten Stimulation des pulmonalen Immunsystems und unabhängig vom Applikationsregime durch MALP-2 vor oder nach Tumorinokulation im Mausmodell keine signifikante Änderung der pulmonalen Metastasen erreicht werden. Durch Markierung von Melanomzellen, die stabil mit Green fluorescent Protein transfiziert waren, war es möglich, Melanomzellen kurz nach Tumorzellaussaat zu untersuchen. Eine lokale TLR2/6-Aktivierung durch MALP-2-Instillation 24 h vor Tumorinokulation führte aber in vivo zu keiner Beeinflussung des pulmonalen Melanomzellarrests im Mausmodell. Außerdem konnte gezeigt werden, dass auch das „Boostern“ des Immunsystems durch wiederholte intratracheale MALP-2-Applikation an bereits etablierten pulmonalen Metastasen zu keiner Änderung des klinischen Gesamtresultates führt. Zusammenfassend kann festgestellt werden, dass diese teilweise unerwarteten Ergebnisse deutlich machen, dass klinische Vorhersagen bezüglich immunmodulierender Therapien mit Vorsicht zu stellen sind, insbesondere, da multiple, sich wechselseitig beeinflussende Effekte durch die Immunstimulantien selbst das Gesamtergebnis einer Tumortherapie beeinflussen können.

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Zhao, Bo [Verfasser]. "Local mRNA expression of vascular cell adhesion molecule-1 (VCAM-1), macrophage colony-stimulating factor (MCSF-1), and its receptor, c-fms, on rabbit heart valves in the early phase after atrioventricular valve surgery and Staphylococcus aureus bacteremia / Bo Zhao." 2004. http://d-nb.info/972046437/34.

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Dissertations / Theses on the topic 'Local Stimulation'

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