The aim of this thesis was to investigate the potential use of hydrogen-bonded organic semiconductors in photostimulation of mammalian cells and the determination of the mechanism thereof.

München, Techn. Univ., Diss., 2000.

The aim of the present work, based on two experiments, was to evaluate the impact of photostimulation as a prevention for delaying the sexual maturation of brook trout (Salvenilus fontinalis). Another additional experiment was to describe which effect has photostimulation on the consequences of aggressive behaviour of males. Two experimental groups were established and differed in illumination sources: the metal halide lamps (HAL) and the light emitting diodes (LED). The photostimulation timing (photoperiod) was tested in following experiment. In both tested groups (HAL and LED) the photoperiod was prolonged to 18L:6D in comparison to the control group with natural photoperiod. The results shows that before spawning females and males in both tested groups (HAL and LED) reached significantly higher body weight up to 100 g (=0.05) due to desirable delayed sexual maturation (up to one month). By obtaining the same results in both groups, clearly profitable source of illumination was LED and the time for sufficient application before spawning was 67 days. Moreover photostimulation had also positively reflected in the elimination of aggressive behaviour of males. The results of the present study suggest that photostimulation may be applicable in the intensive culture systems of salmonids in the Czech Republic.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-22T11:15:04Z No. of bitstreams: 2 Tese - Mariana Alves Mesquita - 2017.pdf: 2201375 bytes, checksum: 148d30a33a0e8c8b215e89ab657bd8d2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-22T11:15:40Z (GMT) No. of bitstreams: 2 Tese - Mariana Alves Mesquita - 2017.pdf: 2201375 bytes, checksum: 148d30a33a0e8c8b215e89ab657bd8d2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-22T11:15:40Z (GMT). No. of bitstreams: 2 Tese - Mariana Alves Mesquita - 2017.pdf: 2201375 bytes, checksum: 148d30a33a0e8c8b215e89ab657bd8d2 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-01 / Two experiments were conducted at North Carolina State University to elucidate the hypothesis that exposing broiler embryos to monochromatic lights during incubation period may influence embryonic growth and development, improving incubation traits and posthatching period. In the first experiment, intermittent green light, continuous green light, intermittent red light and dark were evaluated. In addition, the influence of egg position in the tray was also tested. In the second experiment, monochromatic green light exposure was evaluated during different phases of incubation period. Treatments were: 1) 21d of incubation in the dark; 2) 21d of incubation with green light; 3) dark until E5 and continuous green light until hatch; 4) continuous green light until E5 and dark until hatch; 5) dark until E18 and continuous green light until hatch; 6) continuous green light until E18 and dark until hatch. Machine temperatures were adjusted daily in order to obtain optimal eggshell temperature (99,5 a 100,4°F) during the whole incubation period. In the first trial, embryo mortality in intermediate phase was higher in the group exposed to intermittent green light. Relative proventriculus weight was influenced by light stimuli, and the group that was not exposed to light showed the greatest organ development. Feed intake was also influenced by light treatments at 21 d of age. In the second trial, exposing embryos to continuous green light at different moments during incubation period affected the percentage of hatch and hatch of fertile. In addition, dead pipped was higher in the group exposed to light until E18. Liver weight was higher in chicks incubated in the dark during 21 d. Feed conversion ratio at 35 and 42 days was also influenced by light treatments, and the group that was not exposed to light during the whole incubation period had the lower feed conversion ratio. Significant interaction was observed between light stimuli and sex for breast yield. Male chicks that were light stimulated until E18 had the lowest breast yield. Comparing sexes, the highest breast yield was observed for females that were light stimulated until E18 during incubation. In conclusion, with incubation conditions that were established during the experiments, exposing broiler embryos to monochromatic lights did not promote benefits in incubation traits and also did not influenced chick growth and development in posthatching period. / Foram realizados dois ensaios experimentais na North Carolina State University com o objetivo de elucidar a hipótese de que a exposição de embriões de frangos de corte à luz monocromática durante o período de incubação pode influenciar o crescimento e desenvolvimento embrionário promovendo melhorias no rendimento da incubação e no período pós-eclosão. No primeiro experimento avaliou-se a estimulação com luz monocromática verde intermitente, verde contínua, vermelha intermitente e ausência de luz. Foi testado também a influência da posição dos ovos no interior da bandeja em relação a fonte de luz. No segundo experimento, avaliou-se a exposição deovos à luz verde monocromática durante diferentes fases do período de incubação. Os tratamentos estudados foram: 1) 21 dias de incubação no escuro; 2) 21 dias de incubação com luz verde contínua; 3) escuro até o quinto dia de desenvolvimento embrionário (E5) e luz verde contínua até o nascimento; 4) luz verde contínua até E5 e escuro até o nascimento; 5) escuro até o décimo oitavo dia de desenvolvimento embrionário (E18) e luz verde contínua até o nascimento; 6) luz verde contínua até E18 e escuro até o nascimento. As temperaturas das máquinas, em ambos os experimentos foram reguladas diariamente com o objetivo de se obter uma temperatura ótima da casca do ovo (99,5 a 100,4°F) durante todo o período de desenvolvimento embrionário. No primeiro experimento, o percentual de mortalidade embrionária na fase intermediária foi superior no tratamento exposto à luz verde intermitente. O peso relativo do proventrículo foi influenciado pelos estímulos luminosos, sendo que o grupo que não foi exposto a luz, o que apresentou maior desenvolvimento do órgão. O consumo de ração também foi influenciado pelos tratamentos estudados aos 21dias de idade. No segundo experimento, a exposição à luz verde contínua em diferentes momentos do período de incubação prejudicou os percentuais de eclosão e eclosão sobre férteis. Além disso, o percentual de bicados mortos foi superior no tratamento exposto à luz verde contínua até E18. O peso relativo do fígado foi superior nas aves que permaneceram no escuro durante os 21 dias de incubação. A conversão alimentar aos 35 e 42 dias de idade também foi influenciada pelos tratamentos estudados, sendo que o grupo que não foi exposto à luz durante todo o período de incubação o que apresentou melhor conversão alimentar. Houve interação entre estímulo luminoso e sexo para rendimento de peito, sendo que para machos o menor rendimento de peito foi observado no grupo que recebeu estímulo luminoso até E18. Comparando-se os sexos, constatou-se maior rendimento para fêmeas oriundas de incubação com estímulo luminoso até E18. Concluiu-se que nas condições de incubação estabelecidas durante a realização dos experimentos, a exposição de embriões de frangos de corte à luz monocromática não promoveu benefícios no rendimento da incubação e também não favoreceu o crescimento e desenvolvimento das aves no período pós-eclosão.

L'objectif de ce projet est l’étude de la plasticité des circuits corticaux dans le contexte de l'apprentissage des souris « sauvages » et modèles du syndrome de l’X fragile. Des études sur l'efficacité de la combinaison d'enregistrement des potentiels de champ locaux extracellulaires avec la stimulation laser UV (LSPS) pour cartographier les réseaux ont été réalisées. Nous avons trouvé des enregistrements de champs extracellulaires qui pourraient être utilisés pour détecter les réponses synaptiques évoquées par LSPS. Nos résultats indiquent une méthode alternative pour obtenir des cartes complètes de réseaux intracorticaux excitateurs. Ensuite, nous avons développé un paradigme d'apprentissage associatif sensoriel et étudié ses effets sur les réseaux intracorticaux excitateurs du cortex baril. Ex vivo un affaiblissement des projections excitatrices entre les couches 4 et 2/3 qui dans les colonnes de vibrisses C a été observée. Enfin, nous avons utilisé ces mêmes approches dans une souris modèle du syndrome de l'X fragile (FXS). Pour étudier les liens entre les déficits sensoriels, l'apprentissage associatif et les altérations fonctionnelles des réseaux sensoriels, nous avons utilisé un modèle de souris mutantes dans lequel la pathologie FXS était ciblée sur la couche 4 du cortex somatosensoriel. Il a été constaté que les souris WT présentaient une dépression similaire, alors qu'elle était absente FXS. En conclusion, les études sur les mutants sensoriels de type sauvage ont mis en lumière les conséquences de l'apprentissage sur les réseaux corticaux sensoriels et les liens entre la plasticité des réseaux corticaux sensoriels et les capacités cognitives. / The aim of this project is to study the plasticity of the cortical circuits in the context of the learning of wild type mice and models of Fragile X Syndrome. First, investigations into the efficacy of recording combination of extracellular local field potentials with UV laser stimulation (LSPS) to map networks were performed. We found extracellular field records could be used to detect the synaptic responses evoked by LSPS. Our results indicate an alternative method for obtaining complete maps of excitatory intracortical networks. Next, we developed a sensory associative learning paradigm and studied its effects on excitatory intracortical networks the barrel cortex. Ex vivo a weakening of the excitatory projections between layers 4 and 2/3 which in the columns of vibrissae C was observed and declined function of the speed of the behavioural response. Finally, we used these same approaches in a Fragile X Syndrome (FXS) model mouse. To study the links between sensory deficits, associative learning, and functional alterations of sensory networks, we used a model of mutant mice in which the FXS pathology was targeted to the layer 4 of the somatosensory cortex. Our hypotheses were that behavioural conditioning would change the cortical sensory circuits of the FXS sensory mutant and that the abnormal plasticity of these circuits would in turn affect the performance. It was found the WT mice exhibited a similar depression, whereas it was absent FXS. In conclusion, wild type mouse and FXS sensory mutant studies shed light on the consequences of learning on sensory cortical networks and on the links between plasticity of sensory cortical networks and cognitive abilities.

En vue de la numérisation des images radiologiques, les propriétés luminescentes de l'europium divalent dans diverses familles de composés du strontium ou du baryum comportant un halogène ont été étudiées. Dans les composés riches en halogène (MCl2, M4OCl6, M5SiO4Cl6...) (M=Sr, Ba), l'extinction thermique de l' émission ne débute qu'au-dessus de 300 K. De fortes densités de centres colorés présentant des bandes d'absorption à grande longueur d'onde ont pu être obtenues après irradiation X. La conjonction de ces deux caractéristiques permet, notamment dans le cas des halogènosilicates Sr5SiO4Cl6(1-x)Br6x:Eu, l'obtention de rendements de luminescence photostimulée par laser argon particulièrement élevés.