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Darbo objektas – naujai sukryžminti hibridinės drebulės (Populus tremuloides x Populus tremula) ir karpotojo beržo ( Betula pendula) hibridai. Darbo tikslas – Atlikti tolimąją hibridizaciją ir išauginti augalus-regenerantus nesubrendusių gemalų kultūroje bei įvertinti genetinę įvairovę. Darbo rezultatai. Sukryžminus gauta skirtingi hibridai. Jų įvairovė įvertinta APPD metodu. Išmatavus augimo tempus nustatyta, kad hibridai 16.2 ir 16.4 auga greičiau nei hibridinės drebulės klonai. Ištyrus adaptacijos nesterilioje aplinkoje sąlygas, nustatyta šaknijimosi tempai. Tyrimo metu pastebėta, kad ūgliukų sodinimas į durpių substratą Jiffi tabletėse su šaknimis ir be jų ilgesniam nei 3 mėnesių laikotarpiui, neturi augimo skirtumų. / Aim of the work: new crossbred hybrid aspen (Populus tremuloides x Populus tremula) and birch (Betula pendula) hybrids Objekt of the work: make long hybridization and grow up new regeneration plants in unformed embrio culture and rate genetical variation Results: After crossing get new hybrids. His variation rated by RAPD metod. After measure growing speed, set that hybrids 16.2 and 16.4 growing faster than hybriding aspen clons. In adaptation study set root growing speed. In study notice that plants with root and without in Jiffi tablet peat substratum after 3 month get same height .

Darbo objektas – Populus genties medžiai: Populus alba × Populus tremula (Nr. 20), Populus tremula x Populus alba ( Nr.21), P. tremuloides x P. tremula (Nr.8), P. tremuloides x P. tremula (Nr.3), P. tremuloides x P. tremula (Nr.9), Populus alba (Š16), P. berolinensis. Darbo tikslas – nustatyti tuopų genties medžių hibridų mikrodauginimo in vitro sąlygas, bei augalų- regenerantų išauginimą. Išskirti genominę DNR iš drebulių, naudojant genominės DNR išskyrimo rinkinį NucleoSpin Plant. Darbo metodai - Eksplantų paruošimas sterilinimui ir sterilinimas. Augalų regenerantų kultivavimo sąlygos. Maitinamosios terpės ruošimas, sterilinimas ir sudėtis. Mikroūglių perkėlimas į nesterilias sąlygas. DNR išskyrimas. Darbo rezultatai. Tuopų medžių eksplantų sterilinimui tikslinga naudoti aseptinių tirpalų kombinaciją be „ACE“, kad užtikrinti gyvybingų ir be užkrato eksplantų išlikimą. Grybine infekcija labiausiai užkrėsti berlyninės tuopos eksplantai: užkratas sudarė nuo 72 proc. iki 80 proc. priklausomai nuo eksplantų prigimties. Tuopų genties medžių genotipas turi įtakos morfogenezei audinių kultūroje. Geriausia maitinamoji terpė mikroūglų susidarymui yra Murashige Scoog (MS) su citokininu BA- 0,5 mg/l. Kaliaus susidarymas ir spalva priklauso nuo genotipo. Iš visų tuopų hibridų sparčiausiai augo hibridas Nr. 8 P.( tremuloides x P. tremula). Vidutinis jo augimo greitis- 8,3 mm per 10 dienų. Atlikti DNR tyrimai APPD metodu parodo, kad motinmedžiai ir išauginti augalai in vitro yra... [toliau žr. visą tekstą] / Aim of the work: Genus Populus trees: Populus alba × Populus tremula (Nr. 20), Populus tremula x Populus alba (Nr.21), P. tremuloides x P. tremula (Nr.8), P. tremuloides x P. tremula (Nr.3), P. tremuloides x P. tremula (Nr.9), Populus alba (Š16), P. berolinensis. Object of the work: Investigate poplar genus hybrids in vitro micro reproduction conditions and regenerate plants growth. Investigate poplar genomic DNA using NucleoSpin Plant Kit. Methods: Preparation of explants culture for sterile manner. Plants regenerate rear conditions. Growth media preparation and sterilization. Micro sprout input into unsterile conditions. DNA isolation. Results: For poplar trees explants sterilization is purposeful using aseptic solution combination without “ACE”, to vouch vital and half explants survival. Fungous infection found in berolinensis poplar explants: infections reach from 72 to 80 % depending from explants nature. Poplar genus genotype has impact on morphogenesis in tissue culture. The best growth media is Murashige Scoog (MS) with citotoksine BA- 0,5 mg/l. Callus formation and colaration depends on genotipe. Fastest growth had hybrid No. 8 ( tremuloides x P. tremula) from all poplar hybrids. His mean growth was 8.3 mm per 10 days. RAPD analysis shown that the parent trees and trees race in vitro are the similar (the same).

Nous avons étudié les relations anatomiques entre les systèmes de neurotransmission à substance P (SP) et à sérotonine (5-hydroxytryptamine, 5-HT) dans le noyau du raphé dorsal (NRD) du rongeur, afin de mieux comprendre les interactions entre ces systèmes durant la régulation de l’humeur. Le NRD reçoit une innervation SP provenant de l’habenula, et le blocage pharmacologique des récepteurs neurokinine-1 (rNK1) de la SP aurait des effets antidépresseurs. Chez le rongeur, le traitement par les antagonistes des rNK1 s’accompagne d’une désensibilisation des autorécepteurs 5-HT1A de la 5-HT et d’une hausse de l’activité des neurones 5-HT dans le NRD, suggérant des interactions locales entre ces deux systèmes. Dans un premier temps, nous avons démontré par doubles marquages immunocytochimiques en microscopies optique, confocale et électronique, la présence du rNK1 dans une sous-population de neurones 5-HT du NRD caudal. Lors de l’analyse en microscopie électronique, nous avons pu constater que les rNK1 étaient principalement cytoplasmiques dans les neurones 5-HT et membranaires sur les neurones non 5-HT du noyau. Grâce à d’autres doubles marquages, nous avons aussi pu identifier les neurones non-5-HT porteurs de rNK1 comme étant GABAergiques. Nous avons ensuite combiné l’immunomarquage de la SP avec celui du rNK1, dans le but d’examiner les relations entre les terminaisons (varicosités *) axonales SP et les neurones 5-HT (pourvus de rNK1 cytoplasmiques du NRD caudal. En simple marquage de la SP, nous avons pu estimer à 41% la fréquence avec laquelle les terminaisons SP font synapse. Dans le matériel doublement marqué pour la SP et son récepteur, les terminaisons SP ont été fréquemment retrouvées en contact direct ou à proximité des dendrites munies de rNK1 cytoplasmiques, mais toujours éloignées des dendrites à rNK1 membranaires. Pour tester l’hypothèse d’une internalisation soutenue des rNK1 par la SP dans les neurones 5-HT, nous avons ensuite examiné la localisation subcellulaire du récepteur chez le rat traité avec un antagoniste du rNK1, le RP67580. La densité du marquage des rNK1 a été mesurée dans le cytoplasme et sur la membrane des deux types de dendrites (5-HT: rNK1 cytoplasmiques; non 5-HT: rNK1 membranaires). Une heure après une injection unique de l’antagoniste, la distribution du rNK1 est apparue inchangée dans les deux types de neurones (5-HT et non 5-HT). Par contre, après un traitement quotidien de 7 ou 21 jours avec l’antagoniste, nous avons mesuré une augmentation significative des densités cytoplasmique et membranaire du rNK1 dans les neurones 5-HT, sans aucun changement dans les neurones non 5-HT. Ces traitements ont aussi augmenté l’expression du gène rNK1 dans le NRD. Enfin, nous avons mesuré une hausse de la densité membranaire du rNK1 dans les neurones 5-HT, sans hausse de densité cytoplasmique, par suite d’une lésion bilatérale de l’habenula. Ces résultats confortent l’hypothèse d’une activation et d’une internalisation soutenues des rNK1 par la SP dans les neurones 5-HT du NRD caudal. Ils suggèrent aussi que le trafic des rNK1 dans les neurones 5-HT du NRD représente un mécanisme cellulaire en contrôle de l’activation du système 5-HT par les afférences SP en provenance de l’habenula. / We have studied in detail the relationships between substance P (SP) and serotonin (5-hydroxytryptamine, 5-HT) neurotransmission systems in the dorsal raphe nucleus (DRN) of rodents, in order to further our understanding of their interaction during mood regulation. The DRN receives a SP innervation arising from the habenula and, in human, it is known that blockade of the neurokinin-1 receptor (NK1r) of SP by antagonists may have antidepressant effects. In rodents, treatment with NK1r antagonists is known to increase the firing of DRN 5-HT neurons and to induce a desensitization of their 5-HT1A autoreceptors, suggesting local interactions between the SP and 5-HT systems. In a first step, we were able to demonstrate by means of light, confocal, and electron microscopic immunocytochemistry, including double immunolabelings of NK1r and of the biosynthetic enzyme of 5-HT, tryptophane hydroxylase, the presence of NK1r in a subpopulation of 5-HT neurons in the caudal DRN of rat and mouse. After the dual immunolabelings for electron microscopy, we also found that NK1r was mostly cytoplasmic in 5-HT neurons while predominating on the plasma membrane of TPH negative (non 5-HT) neurons. Subsequently, in additionnal double labeling experiments, we were able to identify most if not all non 5-HT dendrites bearing membranous NK1r as GABAergic. In a second step, we combined the immunolabeling of SP with that of NK1r, in order to examine the relationships between SP axon terminals (varicosities *) and the two categories of DRN neurons (5-HT: cytoplasmic NK1r; non 5-HT: membranous NK1r). After single SP labeling, we could estimate the frequency with which SP terminals made synapse at 41%, at least. In the material doubly labeled for SP and NK1r, the SP terminals were often found in close contact or in the immediate proximity of dendrites endowed with cytoplasmic receptor, but never near non 5-HT dendrites bearing membrane bound receptors. To test the hypothesis of a sustained internalization of NK1r in 5-HT neurons, we then tested the effects of RP67580, a selective NK1r antagonist, on the subcellular localization of the receptor. One hour after administration of a single dose, the NK1r distribution was unchanged in both types of dendrites (5-HT and non 5-HT). However, after administration for 7 (subchronic) or 21 (chronic) days, the cytoplasmic and the membrane densities of NK1r were significantly increased in 5-HT dendrites, without any change in non 5-HT dendrites. These treatments also increased NK1r gene expression in the caudal DRN. Lastly, a significant increase in the membrane density of NK1r was measured in the 5-HT neurons, without any increase of the cytoplamic density, following bilateral electrolytic lesioning of the habenula. These results strenghtened the hypothesis of a sustained activation and internalization of NK1r by SP in 5-HT neurons of the caudal DRN. They also suggested that trafficking of NK1r in these cells might represent a cellular mechanism in control of the activation of the 5-HT system by SP afferents from the habebula.

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Rice production in Sub-Sahara Africa is hampered by drought stress, low farmer adoption of improved varieties, un-adapted germplasm, problems of crossability between species and problems of efficient emasculation. This study was initiated to: (1) determine farmer preferences for rice varieties and production practices, (2) identify drought tolerant parental lines for use in interspecific crosses, (3) determine crossability between different rice species, (4) identify drought tolerant interspecific segregants from crosses, and (5) study the efficacy of ethrel and gibberrilic acid (GA3) as chemical hybridising agents. Participatory rural appraisal (PRA) was conducted in Sikasso region in the month of September 2005 to determine farmer preferences for varieties and production constraints. A total of 125 rice farmers from 10 villages participated. This study found that farmer preferences for rice traits did not coincide with the breeders' objectives and trait preferences varied across ecologies. In upland and lowland rice ecologies, the most preferred characteristic was short duration. In the lowland tall plants was most preferred and short duration trait ranked second. Long duration ranked as the second most preferred trait after yield in the irrigated rice ecology. The estimated grain yield reduction was 60% due to drought stress from all ecologies. Sixteen genotypes including seven Oryza glaberrima Steud, six interspecific (0. saliva x 0. glaberrima) inbred genotypes and two improved 0. saliva L. subsp Gaponica) genotypes, with OS 6, as drought tolerant check were screened for drought tolerance at the vegetative stage during the dry seasons of 2004 and 2005 at Samanko research station, in Mali. Most of the genotypes could be regarded as exhibiting drought tolerance and avoidance mechanisms for most of the morpho-physiological characters under study. High selection index was observed for WAB 450-I-B-P-103-HB in the two season experiments. Drought stress tolerance (little leaf drying) was significantly correlated with leaf rolling, leaf area index, and plant height. Fast drought recovery was significantly correlated with drought tolerance, tiller number and leaf area index. Effects of genotypes, environment and their interactions were significant for tiller number, root dry weight and relative leaf water content. The most stable genotype was RAM 3 for tiller number and relative leaf water content. Thirteen genotypes were selected on the basis of these traits for rice hybridisation. A factorial arrangement involving three levels of gametocide concentrations and five application stages of the female rice parent was undertaken for each gametocide ethrel and GA3 for two seasons. Per cent empty spikelets and male sterility increased with concentration of ethrel. Male sterility induction of 41.5% and 42.8% at 2000 ppm was achieved in 2004 and 2005, respectively, while at 4000 ppm male sterility induction was 40.5 % and 46.1% in 2004 and 2005, respectively. The best application stage of ethrel that induced highest male sterility was at P4 (panicle primordium differentiation + spikelet primordium differentiation) of 46.6% in 2004 and 49.2% at PI (panicle primordium differentiation) in 2005. There was no measurement on GA3 for sterility due to lodging. Total male sterility was not achieved therefore, these gametocides could not be recommended for use as hybridising agents. Crossability was studied in four groups: group A (0. glaberrima x 0. saliva), group B (0. glaberrima x Interspecific), group C (Interspecific x 0. saliva) and group D (Interspecifics x Interspecific). High percent seed set was obtained in group D of 19.08% and group A had 9.29%, in group B the seed set was 11.26% and group Chad 6.62 %. The three best combiners as female parents based on percentage seed set were CG 14 (0.glaberrima), WAB 450-IBP-I05-HB and WAB450-I-B-P-I03-HB (interspecifics), and for male parents were NERICA 3, NERICA 2 (interspecifics) and WAB 375-B-9-H3-2 (0. sativa). Genetic components of variance and heritability estimates were studied in F3 and F4 generation progenies from North Carolina II design mating scheme. General combining ability (GCA), manly due to female and specific combining ability (SCA) were significant for tiller number, plant height and specific leaf dry weight indicating that additive and non-additive genetic effects controlled these traits. Heritability estimates for drought tolerance and leaf rolling were highly significant for all the populations examined, ranging from 0.32 to 0.72 and 0.22 to 0.56, respectively. Drought tolerance expressed as little leaf drying was significantly associated with less leaf rolling, larger leaf area index, and taller plants. Some genotypes and progenies such as WBK 39-B-B-B, WBK 30-B-B and WAB 450-I-B-P-I03-HB were identified as being drought tolerant with the ability to recover quickly from drought stress. There was a strong desire for tall plants and short duration rice in upland and lowland ecologies, while high yield was preferred in irrigated ecology. Therefore, the best breeding strategy would be ecosystem breeding targeting each of the ecologies. Screening for secondary traits that have been identified to be significantly associated with rice grain yield could be used for direct selection for grain yield under drought stressed conditions. Progenies identified, as drought tolerant would be considered for use as source germplasm in breeding that target Sikasso region and any other similar ecologies. This study therefore suggested that participatory research approaches that involve all stakeholders in rice production would be valuable in identifying and generating drought tolerant and adoptable rice cultivars in the tropics of Africa with considerable impact on food security. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

EphA7 est un membre de la famille des récepteurs à tyrosine kinase Eph, qui régulent l’adhérence et la motilité cellulaires. EphA7 est hautement conservé chez les vertébrés et largement exprimé durant l'embryogenèse, en particulier pendant le développement du SNC. Dans le cerveau adulte, EphA7 est transcrit principalement dans l'hippocampe, avec de faibles niveaux d'expression ailleurs. Nous avons cartographié sa distribution dans le cerveau du rat et de la souris adultes, par hybridation in situ et immunohistochimie en microscopie photonique et électronique. Les deux méthodes montrent une distribution de marquage très cohérente. Le signal le plus fort a été observé dans l’hippocampe, avec des niveaux moins élevés dans l’habénula, le striatum, l’amygdale, les cortex cingulaire, piriforme et entorhinal, ainsi que le cervelet. Au niveau ultrastructural, dans l’hippocampe, l’immunoréactivité d’EphA7 a été localisée dans le cytoplasme des cellules granulaires (gyrus dentelé) et pyramidales (CA1 et CA3) en ordre décroissant d’intensité. Dans le neuropile de CA1, des épines dendritiques et des prolongements astrocytaires, souvent périsynaptiques, ont été les éléments le plus fréquemment marqués. Plus rarement, nous avons aussi rencontré des dendrites et des terminaisons axonales immunopositives. La localisation préférentielle d’EphA7 dans les épines dendritiques et les prolongements astrocytaires périsynaptiques est conséquente avec un rôle de ce récepteur dans la plasticité synaptique / Abstract: EphA7 is a member of the family of Eph receptor tyrosine kinases, which regulate cell adhesion and motility. EphA7 is highly conserved in vertebrates and widely expressed during embryogenesis, especially during the development of the CNS. In the adult brain, EphA7 is transcribed mainly in the hippocampus, with low expression levels elsewhere. We have mapped its distribution in the adult brain of rat and mice by in situ hybridization and by immunohistochemistry in light and electron microscopy. Both methods show very consistent labelling distribution. The strongest signal was observed in the hippocampus, but modest levels were detected in the habenula, striatum, amygdala, the cingulate, piriform and entorhinal cortex, and the cerebellum. At the ultrastructural level, in the hippocampus, EphA7 immunoreactivity was localized in the cytoplasm of granule (dentate gyrus) and pyramidal cells (CA1 and CA3) in descending order of intensity. In the neuropil of CA1, dendritic spines and astrocytic processes, often perisynaptic were the most frequently labelled. More rarely, we also observed immunopositive dendrites and axon terminals. The preferential localization of EphA7 in dendritic spines and perisynaptic astrocytic processes is consistent with a role of this receptor in synaptic plasticity / Bourse de maîtrise du Groupe de recherche sur le système nerveux central GRSNC, (2009,2010) Bourse d’études supérieures du Canada Frederick Banting et Charles Best, IRSC Instituts de recherche en santé du Canada, (2011)

This paper is aimed at mapping important traits in a Hiberno-Norse identity. This is the main focus of the essay, but another important part is to problematize this using several theoretical approaches of which the main are identity, creolization and hybridization. The Hiberno-Norse culture being primarily an urban phenomenon, the thesis is delimited to the Hiberno-Norse towns with occasional comparisons to Scandinavia to see how the native Irish population influenced the invaders and how they gradually evolved into the Hiberno-Norse. Early on the Norse show signs of creolization that would ultimately lead to the creation of the Hiberno-Norse hybrid culture known from history and archaeology – an urban culture that show blended Norse and Irish features. / Denna uppsats är till för att sammanställa viktiga uttryck I en Iro-Skandinavisk identitet. Detta är huvudsyftet med uppsatsen, men en annan viktig del är att problematisera detta genom flera teoretiska begrepp, där de främsta är identitet, kreolisering och hybridisering. Då den Iro-Skandinaviska kulturen framför allt var ett urbant fenomen har uppsatsen avgränsats till de Iro-Skandinaviska städerna, med sporadiska jämförelser med Skandinavien för att se hur den inhemska Irländska befolkningen influerade angriparna och hur de skulle komma att utvecklas till Iro-Skandinaverna. Tidigt uppvisar nordborna tecken på kreolisering, som till slut skulle leda till uppkomsten av den Iro-Skandinaviska hybridkulturen känd från historian och arkeologin – en urban kultur som uppvisar blandade nordiska och irländska drag.