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Models for the Transfer of Drugs from the Nasal Cavity to the Central Nervous SystemJansson, Björn January 2004 (has links)
The blood-brain barrier restricts the access of many compounds, including therapeutic agents, to the brain. Several human studies indicate that nasal administration of hydrophilic compounds, such as peptides, can bypass the blood-brain barrier. The aims of this thesis were to develop and refine models for this direct nose-to-brain transfer. In a mouse model, [3H]-dopamine was given as a unilateral nasal dose. The resulting radioactivity in the ipsilateral olfactory bulb was significantly higher than that in the contralateral bulb and peaked at 4 h. Tape section autoradiography showed that the radioactivity was concentrated in the olfactory nerve layer and the glomerular layer of the olfactory bulb. The olfactory transfer of dopamine was also studied in vitro. At a lower donor concentration, the mucosal-to-serosal dopamine permeability was higher than the serosal-to-mucosal permeability, but at a higher concentration, the permeability coefficients were similar. Together, these results suggest that the olfactory transfer of dopamine has an active component. Olfactory transfer of fluorescein-labeled dextran through the epithelium and deeper tissues was studied in a rat model, which enabled visualization of the transfer using fluorescence microscopy. Although the epithelial transfer appeared to be mainly intracellular, transfer in the following deeper tissues was extracellular. Without altering the route of uptake, a gellan gum formulation enhanced the uptake of fluorescein dextran. The enhancing effect was considered likely to be the result of an increased residence time in the nasal cavity. In conclusion, dopamine and fluorescein-labeled dextran were identified as suitable model compounds for the study of olfactory drug transfer mechanisms and the influence of drug formulation. Two new in vitro models of olfactory transfer were compared. Also, a rat model, which enabled the visualization of the entire nose-to-brain transfer, was developed.
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Olfactory Transfer of Analgesic Drugs After Nasal AdministrationEspefält Westin, Ulrika January 2007 (has links)
Nasal administration of analgesics for achieving rapid pain relief is currently a topic of great interest. The blood-brain barrier (BBB) restricts access to the central nervous system (CNS) for several central-acting drugs, such as morphine and dihydroergotamine, which results in a substantial effect delay. Evidence for the olfactory transfer of drugs from the nasal cavity to the CNS after nasal administration, bypassing the BBB, is available for both animals and humans. The aims of this thesis were to study the olfactory transfer of morphine to the CNS after nasal administration, and to compare the nasal transport of analgesic drugs across nasal respiratory and olfactory mucosa. In vivo studies in rodents demonstrated that morphine is transferred via olfactory pathways to the olfactory bulbs and the longitudinal fissure of the brain after nasal administration. Further, olfactory transfer of morphine significantly contributed to the early high morphine brain hemisphere concentrations seen after nasal administration to rats. Olfactory transfer was tracked by collecting and analysing brain tissue and blood samples after right-sided nasal administration and comparing the results to the situation after i.v. administration. The olfactory transfer was also visualised by brain autoradiography. In vitro studies indicated that the olfactory mucosa should not be a major barrier to the olfactory transfer of dihydroergotamine or morphine, since transport of these drugs was no more restricted across the olfactory mucosa than across the nasal respiratory mucosa. The in vitro studies were performed using the horizontal Ussing chamber method. This method was further developed to enable comparison of drug transport across nasal respiratory and olfactory mucosa which cannot be achieved in vivo. In conclusion, these analgesic drugs showed potential for olfactory transfer, and access to the CNS by this route should be further investigated in humans, especially for the drugs with central effects that are currently under development for nasal administration.
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Diversity of transduction mechanisms in receptor neurons of the main olfactory epithelium in <i>Xenopus laevis</i> tadpoles / Vielfalt von Transduktionsmechanismen in Rezeptorzellen des olfaktorischen Epithels der Hauptkammer von larvalen <i>Xenopus laevis</i>Manzini, Ivan 29 January 2003 (has links)
No description available.
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Investigation of spatio-temporal coding in the olfactory bulb of larval Xenopus laevis using fast confocal imaging / Untersuchung der räumlich-zeitlichen Reizkodierung im bulbus olfactorius von Xenopus laevis Larven mittels schneller konfokaler BildgebungJunek, Stephan 21 January 2009 (has links)
No description available.
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Glödljus vs. LED-ljus : En rumslig analys av ljuskvalitén i hemmiljö / Incandescent light vs. LED light : A spatial analysis of lighting quality in home environmentsAttila, Csikós January 2014 (has links)
Det finns fortfarande för många hushåll i Sverige som använder mest glödljus för belysning, i form av glödlampor eller halogenlampor. Detta orsakar en väsentlig del av det onödiga överskott av koldioxidutsläpp som är en av orsakerna till den globala uppvärmningen. Därför avser detta examensarbete att försöka skapa en grönare miljö genom att studera och uppmärksamma faktorer som påverkar val av ljuskällor i belysningssammanhang. Syftet med examensarbetet är att få en ökad förståelse för hur LED-ljuset upplevs i hemmiljö. Arbetet ska visa hur LED-ljuskällans nuvarande kvalité bedöms utifrån individuella rumsupplevelser samt om ytterligare kvalitetsförbättringar behövs. Detta görs för att kunna vända allmänhetens inställning i en mer positiv riktning gentemot LED, vilket kan bidra till en mer ekologiskt hållbar miljö. För att undersöka hur LED fungerar i hemmiljö genomfördes en experimentell studie med syfte att besvara följande frågor: hur upplevs LED-ljusets kvalité jämfört med halogenljusets, hur tror man att det egna välmåendet påverkas av halogenljus respektive LED-ljus, hur påverkas rumsupplevelsen och rumskaraktären om halogenljus ersätts med LED-ljus och finns det några skillnader mellan ljusdesigners och icke ljusdesigners upplevelse av halogenljus och LED-ljus i hemmiljö? Det byggdes upp två likadana försöksrum som hade samma förutsättningar både storleksmässigt, inredningsmässigt och belysningsmässigt. Den enda skillnaden var de installerade ljuskällorna, då det användes halogenlampor i det ena rummet och LED-lampor i det andra rummet. En enkätundersökning genomfördes, resultatet analyserades och en utförlig rumsanalys gjordes. Resultatet visade att ljuset, oavsett ljuskälla, påverkade deltagarnas välmående och rumsupplevelse på olika sätt, beroende på vilken yrkesgrupp de tillhörde. Det visade sig också att skillnaden i ljuskvalitén mellan halogenljus och LED-ljus inte längre är omfattande. Dagens LED-lampor utvecklas alltså positivt och är redan en värdig ersättare till glöd- och halogenlampor. / There are still too many households in Sweden that use mostly incandescent light for lighting, using incandescent or halogen bulbs. This causes a substantial part of the unnecessary surplus of carbon-dioxide that is one of the reasons for global warming. Therefore, this degree project aims to promote a greener environment by studying and paying attention to factors that have an influence in the lighting context. The purpose of this degree project is to gain a better understanding of how the LED light is experienced in a home environment. The work will show how LED light source's current quality is evaluated based on individual room experiences, and if additional quality improvements are needed. The objective is to turn the public's attitude in a more positive direction where LED can contribute to a more ecologically sustainable environment. To investigate how LEDs are perceived in home environments an experimental study was performed which was based on the following research questions: How is LED light quality experienced compared to halogen light, how is personal wellbeing perceived in relationship to halogen and LED light, how are room experience and room character affected if halogen light is replaced by LED light in a home environment and are there any differences in these experiences between lighting designers and non lighting designers? Two identical test-rooms were used. They were identical in size, interior design and lighting design. Halogen bulbs were used in one room and LED lights were used in the other room. A survey was used to get answers to the questions above. The results have been analyzed and detailed room analysis was also made. The results showed that the light, regardless of light-source, influenced the participant's well-being and their room experience in different ways, depending on the occupational group they belonged to. It was also found that the difference in quality of light between halogen light and LED light is no longer significant. The presently available LED lights are improving and are worthy replacements for incandescent and halogen lamps.
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Fluxo tridimensional de água no solo: aplicação de volumes finitos na simulação da irrigação por gotejamento superficial / Soil water three-dimensional flow: finite volumes application in the surface drip irrigation simulationSouza, Luiz Ailton de Araújo 06 March 2009 (has links)
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Previous issue date: 2009-03-06 / In this work, a mathematical model was developed for the simulation of soil water movement under surface drip irrigation, being used the method of the finite volumes for the resolution of the partial differential equation of water flow in porous media. The soil water flow was treated three-dimensionally for the determination of your movement in the infiltration and redistribution phases. The model allows the determination dimensions and shape of the wetted bulb, of the partial and final dimension of the saturated disc radius and the determination of the saturated soil volume, when to deal about of isolated bulb. In the case of overlapping bulbs, the model allows the determination of the width and depth of the formed wetted strip, making possible the choice of the drippers spacing that better it is adapted to the conditions of the irrigation project and management. A computational program was developed with base in the model, and the obtained results were validated starting from comparisons with field data and results of simulations of other models. These comparisons demonstrated that the model presents reliable results and it can be used as tool for the designing of drip irrigation installations. The sensibility analysis accomplished starting from the variation of some parameters of the soil and of the emitter (initial moisture, saturated soil hydraulic conductivity and trickle discharge), it demonstrated that, with relationship to the final moisture inside of the bulb, the model is so much relatively sensitive to positive variations as negatives of those parameters. / Neste trabalho, foi desenvolvido um modelo matemático para a simulação do movimento de água no solo sob irrigação por gotejamento superficial, utilizando-se o método dos volumes finitos para a resolução da equação diferencial parcial de escoamento de água em meios porosos. O fluxo de água no solo foi tratado tridimensionalmente para a determinação do seu movimento nas fases de infiltração e redistribuição. O modelo permite a determinação da forma e das dimensões do bulbo molhado, da dimensão parcial e final do raio do disco saturado e a determinação do volume de solo saturado, quando tratar-se de bulbo isolado. No caso de bulbos sobrepostos, o modelo permite a determinação da largura e profundidade da faixa molhada formada, possibilitando a escolha do espaçamento entre gotejadores que melhor se adeque às condições do projeto e manejo da irrigação. Um programa computacional foi desenvolvido com base no modelo, e os resultados obtidos foram validados a partir de comparações com dados de campo e resultados de simulações de outros modelos. Estas comparações demonstraram que o modelo apresenta resultados confiáveis e pode ser utilizado como ferramenta para o dimensionamento de instalações de irrigação por gotejamento. A análise de sensibilidade realizada a partir da variação de alguns parâmetros do solo e do emissor (umidade inicial, condutividade hidráulica do solo saturado e vazão do gotejador), demonstrou que, com relação à umidade final dentro do bulbo, o modelo é relativamente sensível tanto à variações positivas quanto negativas desses parâmetros.
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Signatures neurales de la perception hédonique des odeurs chez la souris / Neural bases of odor hedonics in miceMidroit, Maellie 26 January 2018 (has links)
Chez l'homme comme chez l'animal, les odeurs guident le comportement et motivent à agir. La valeur hédonique (le caractère plus ou moins plaisant) est la dimension olfactive principale et est généralement utilisée pour décider d'approcher ou fuir la source odorante. Bien que cette attractivité soit façonnée par l'expérience, certaines odeurs non-familières sont spontanément attractives ou répulsives. Le caractère plus ou moins plaisant d'une odeur serait, du moins en partie, inné. Il existerait ainsi une signature neurale spécifique de la valeur hédonique des odeurs, et c'est ce que cette thèse s'emploie à identifier.Après sélection d'odorants spontanément plus ou moins attractifs (plaisant et déplaisants respectivement), nous avons recherché les bases neurales qui sous-tendent ces comportements. Nous avons tout d'abord cartographié (expression de Zif268) puis manipulé (optogénétique) l'activité neuronale du bulbe olfactif en réponse à ces odorants, et avons révélé une signature neurale bulbaire de la valeur hédonique des odeurs le long de l'axe antéro-postérieur.Puis, afin d'analyser comment le message hédonique était interprété par les aires olfactives et associatives supérieures, nous avons développé une méthode de recalage de l'activité cérébrale dans un atlas de référence, assurant une cartographie rapide, précise et fiable de cette activité. Enfin, en combinant cette méthode à des approches comportementales, électrophysiologiques et pharmacologiques, nous avons montré un rôle du système de la récompense dans le codage de la valeur hédonique des odeurs et qu'une odeur peut être perçue comme une récompense, motivant alors les comportements d'approche et de retrait / In humans and animals, odors guide behavior and motivate action. The hedonic value (that is the pleasantness) is the main olfactory dimension and is generally used to decide to approach the odor source or move away. While this attractiveness is shaped by experience, some unfamiliar odors are spontaneously attractive or repulsive. The pleasantness of an odor would be, at least in part, innate, and suggest a specific neural signature of the hedonic value of odors. The global aim of this thesis is to decipher neuronal mechanisms underlying the hedonic value of odors.After having selected odorants with various level of attraction (pleasant and unpleasant), we have deciphered the neural bases that underlie these behaviors.We first mapped (expression of Zif268) and then manipulated (optogenetic) the neuronal activity of the olfactory bulb in response to these odors, and have revealed a bulbar neural signature of the hedonic value of odors along the antero-posterior axis.Then, in order to analyze how the hedonic information was interpreted by the higher olfactory and associative areas, we developed a method allowing the registration of brain activity in a reference atlas, that ensure a fast, accurate and reliable mapping of this activity. Finally, by combining this method with behavioral, electrophysiological and pharmacological approaches, we have shown a role of the reward system in the coding of odor hedonics and that an odor can act as a reward, thus motivating behavior, approach and withdrawal
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Forenzní analýza prostředí IoT ze stop síťové komunikace / Forensic Analysis of the IoT Environment from Network Communication TracesSlámová, Hana January 2021 (has links)
The goal of this master's thesis is a creation of dataset capturing selected users' activities, network analysis of this dataset, design and implementation of method to detect selected users' activities and discussion of achieved results. 4 devices have been chosen for the creation of this dataset.
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Návrh veřejného osvětlení obce / Proposal of the village public lightingSchittenhelm, Dominik January 2016 (has links)
The thesis is divided into several parts. The first part is theoretical and its main focus is the description of public lighting and the theory regarding lighting technology. The second part continues with the research of the current state in Bezděkov village. The thesis further describes the proposal for the village public lighting with the use of HPS and LED technology, where village models are made for both options to show the requested result. The last part of the work deals with cables dimensioning, the selection of the most effective regulations for lighting, and finally the economic assessment of both projects, while both the investment expenses and the public lighting service fees for the next 20 years are included.
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Měření kvality osvětlení na operačních sálech / Measurement of operating room lights qualityRovná, Tereza January 2016 (has links)
This thesis is focused on measuring the quality of lighting in operating rooms. Operating lights are very demanding in terms of quality requirements for each parameter, so it is important to specify exactly these parameters and check them regurarly. To measure the quality of the light source, was used a special kit from Maquet. Measurement procedure was not as accurate as it was for operating lighting need, therefore, this work includes a proposal to improve the measurement of quality lighting in operating theaters. In cooperation with University Hospital Brno Bohunice University Hospital Motol and the company Maquet measured nine operating lights, each light were compared in terms of parameters such as maximum light intensity, light distribution in the surgical field. In each category were selected several lighting, which reached the best results. The various parameters were compared with values declared by the manufacturer.
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