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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
541

Estrutura genética de zonas de hibridação natural entre Epidendrum fulgens e E. puniceoluteum (Orchidaceae) / Genetic structure of natural hybrid zones between Epidendrum fulgens and E. puniceoluteum (Orchidaceae)

Fabio Pinheiro 25 February 2010 (has links)
Epidendrum L. é o maior gênero de Orchidaceae da região Neotropical com cerca de 1500 espécies, e os processos de diversificação no grupo são pouco conhecidos. Apesar de existirem muitos relatos sobre hibridação no gênero, não há trabalhos que tenham testado essa hipótese em populações naturais. Epidendrum fulgens Brongn. e E. puniceoluteum F. Pinheiro & F. Barros são espécies que ocorrem ao longo do litoral brasileiro, freqüentemente em simpatria. Para testar a eficiência de suas barreiras reprodutivas, foi examinada a distribuição da variação genética dentro e entre populações simpátricas e alopátricas dessas duas espécies. Nove loci de microsatélites nucleares, e cinco loci de microssatélites de cloroplasto foram utilizados para genotipar 463 indivíduos de oito populações, ao longo de toda distribuição geográfica das espécies. A utilização de métodos de atribuição Bayesianos (programas STRUCTURE e NEWHYBRIDS) detectou a existência de grande quantidade de híbridos nas populações simpátricas. As zonas de hibridação são constituídas por híbridos F1, F2 e retrocruzamentos. A introgressão foi assimétrica, ocorrendo preferencialmente de E. fulgens para E. puniceoluteum. Na população da Ilha do Cardoso, foi detectada a predominância de indivíduos F1 e F2, enquanto nas demais localidades a maior parte dos indivíduos híbridos foi identificada como sendo retrocruzamentos na direção de E. puniceoluteum. Em Florianópolis, não foi possível observar a existência de indivíduos puros de E. puniceoluteum, apenas indivíduos exibindo fortes sinais de introgressão, revelando que o processo de hibridação pode interferir na integridade genética das espécies, levando um dos parentais à extinção. O presente estudo sugere que hibridação e introgressão podem ter papel importante na diversificação em Epidendrum e mostra a importância de investigar zonas de hibridação para melhor entender as barreiras reprodutivas e os processos de especiação nas espécies neotropicais de orquídeas. / Among members of the genus Epidendrum , the largest orchid genus of the Neotropics, E. fulgens and E. puniceoluteum occur along the seashore in Brazilian Atlantic Rainforest in sympatric populations. To test the strength of their reproductive barriers, we examined the distribution of genetic variation within and among sympatric and allopatric populations of these two species. Nine specifically developed nuclear microsatellite loci and five chloroplast microsatellite loci were used to genotype 463 individuals from eight populations across species geographical range. All six sympatric populations analyzed present hybrid zones, indicating that hybridization between E. fulgens and E. puniceoluteum is a common phenomenon. Bayesian assignment analysis detected the presence of F1 and F2 individuals, and signs of introgression as well, demonstrating a high potential for interspecific gene flow. The introgression patterns are assimetrical, with differences among populations. Introgression occurs preferentially from E. fulgens to E. puniceoluteum. In Florianópolis population the hybridization seems to lead a species erosion, where pure individuals of E. puniceoluteum where not found. This study suggests that hybridization and introgression could play an important role in the diversification of Epidendrum , and indicated the importance to investigate hybrid zones for better understanding reproductive barriers and speciation processes in Neotropical orchid species.
542

Evaluation of high recombinant protein secretion phenotype of saccharomyces cerevisiae segregant

Sibanda, Ntsako January 2016 (has links)
Thesis (MSc. (Biochemistry)) --University of Limpopo, 2016 / The ever increasing cost of fossil-based fuels and the accompanying concerns about their impact on the environment is driving research towards clean and renewable sources of energy. Bioethanol has the potential to be a replacement for liquid transportation fuels. In addition to its near zero nett carbon dioxide emissions, bio-ethanol has a high energy to weight ratio and can easily be stored in high volumes. To produce bioethanol at economically competitive prices, the major cost in the production process needs to be addressed. The addition of enzymes to hydrolyse the lignocellulosic fraction of the agricultural waste to simple sugars is considered to be the major contributor to high production cost. A consolidated bioprocess (CBP) which ideally combines all the steps that are currently accomplished in different reactors by different microorganisms into a single process step would be a more economically feasible solution. In this study the potential of yeast hybridization with a CBP approach was used. In order to evaluate the reduction or elimination of the addition of cellulolytic and hemi-cellulolytic enzymes to the ethanol production process. High cellobiohydrolase I secreting progeny from hybridization of an industrial bioethanol yeast strain, S. cerevisiae M0341, and a laboratory strain S. cerevisiae Y294 were isolated. In order to determine if this characteristic was specific to cellobiohydrolase I secretion, these strains were evaluated for their ability to secrete other relevant recombinant hydrolase enzymes for CBP-based ethanol production. A total of seven S. cerevisiae strains were chosen from a progeny pool of 28 supersecreting hybrids and reconstructed to create two parental strains; S. cerevisiae M0341 and S. cerevisiae Y294, together with their hybrid segregants strains H3M1, H3M28, H3H29, H3K27 and H3O23. Three episomal plasmids namely pNS201, pNS202 and pNS203 were constructed; these plasmids together with two already available plasmids, namely pRDH166 and pRDH182 contained genes for different reporter enzymes, namely β-glucosidase I, xylanase II, endoglucanase lll, cellobiohydrolase l and α-glucuronidase. To allow for selection of the episomal plasmids, homologous recombination was used to replace the functional URA3 gene of selected strains, with the non-functional ura3 allele from the Y294 strain. Enzyme activity was used as an indicator of the amount of enzyme secreted. Fermentation studies in a bioreactor were used to determine the metabolic burden imposed on the segregants expressing the cellobiohydrolase at high levels. In addition all segregants were tested for resistance to inhibitors commonly found in pre-treated lignocellulosic material. The M28_Cel7A was found to be the best secretor of Cel7A (Cellobiohydrolase l); however it seems as though this phenomenon imposes a significant metabolic burden on the yeast. The supersecreting hybrid strains cannot tolerate lignocellulosic inhibitors at concentrations commonly produced during pretreatment / The National Research Foundation - Renewable Energy Scholarship (NRF-RSES)
543

Generation of a MOR-CreER knock-in mouse line to study cells and neural circuits involved in mu opioid receptor signaling / ミューオピオイド受容体(MOR)のシグナル伝達および神経回路制御機構解析を目的とするMOR-CreERノックインマウスの開発

Okunomiya, Taro 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22366号 / 医博第4607号 / 新制||医||1043(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 林 康紀, 教授 岩田 想, 教授 高橋 淳 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
544

Portrait mummies in context

Boender, Alexandra January 2021 (has links)
The present thesis aims to expand and acquire new knowledge on the emergence of portrait mummies during the Roman period in Egypt and their socio-religious status. The emergence and decorative program of these mummies are commonly understood as an artistic expression of Hellenistic Greek and Roman settlers in Egypt. This attestation is often based upon uncontextualized isolated portraits. The study of uncontextualized isolated portraits has also caused an unsatisfactory approach to dating criteria. In response, the present thesis aims to study contextualized portrait mummies – with the image of the deceased still forming part of the mummy and ideally with an attested find spot – in light of a multicultural society consisting of Egyptian, Hellenistic and Roman cultural and religious traditions.  A total of 85 portrait mummies have been collected to provide context for the expressed cultural traditions. Seven group burials have been reconstructed based upon excavation reports for further contextualization. The results of the collected portrait mummies and reconstructed group burials are subsequently studied against a background of Egyptian, Hellenistic and Roman cultural and religious traditions to highlight dominant cultural features. The results of the present thesis illustrate portrait mummies were an expression of a culturally complex society. The treatment of the body and decorative program suggests cultural and religious notions were rooted within Egyptian traditions that were appropriated, re-defined and adapted by a society comprised of Egyptians, Hellenes and Romans. Portrait mummies consequently express multiple cultural layers. Previously established dating criteria were found to remain to be the most valid and reliable. Contextualized portrait mummies, however, have put forward a new dating criterion that ought to be taken into consideration: octagonal framing.
545

Homoeologous Recombination-Based Chromosome Engineering for Physical Mapping and Introgression in Wheat and Its Relatives Aegilops speltoides and Thinopyrum elongatum

Zhang, Mingyi January 2020 (has links)
Wheat (genome AABBDD) is one of the essential crops, offering approximate 20% of human calorie consumption worldwide. Allopolyploidization of three diploid ancestors led to hexaploid wheat with narrowed genetic variation. Chromosome engineering is an applicable approach to restore the evolutionarily-omitted genetic diversity by homoeologous chromosomes recombination between wheat and its relatives. Two diploid relatives of wheat, Thinopyrum elongatum (genome EE) and Aegilops speltoides (genome SS), containing favorable genes, are used as gene resources for alien introgression and genome diversification in wheat. An advanced and effective experiment procedure was developed and applied for the production, recovery, detection, and characterization of homoeologous recombinants. Meanwhile, a novel recombinant chromosome recovery strategy was exploited with improved efficiency and accuracy. In this study, recombinants of wheat chromosomes 3B and 7B with their homoeologous chromosomes in Th. elongatum and Ae. speltoides (i.e. 3B-3E, 7B-7E, and 7B-7S) were produced and detected. Totolly, 81 3B-3E recombinants and four aberrations involving in distinct chromosomal regions were developed in three recombination cycles by fluorescent genomic in situ hybridization (FGISH). The secondary and tertiary recombination breakpoints occurred toward the proximal regions comparing to the primary recombination under this advanced recombination procedure. A novel recovery strategy was used to recover 7B-7E and 7B-7S homoeologous recombinants by chromosome-specific markers and FGISH verification. Marker-based pre-screening and subsequent FGISH verification identified 29 7B-7E and 61 7B- 7S recombinants, seven 7B-7E and four 7B-7S Robertsonian translocations, one 7E and five 7S telocentric chromosomes, and three 7S deletions. All the recombinants and aberrations were genotyped by high-throughput wheat 90K single nucleotide polymorphism (SNP) assay and the recombination breakpoints were physically mapped to wheat chromosome 3B or 7B according to their FGISH patterns, SNP results, and wheat reference genome sequence. Chromosome 3B was physically partitioned into 38 bins with 429 SNPs. Meanwhile, 44 distinct bins were resolved for chromosome 7B with 523 SNPs. A composite bin map was constructed for chromosomes 3B and 7B, respectively, with a comprehensive analysis of FGISH and SNPs results. In summary, this project provides a unique physical framework for further wheat genome studies and diversifies the wheat genome for germplasm development in wheat breeding.
546

Nuclear Structure Studied by Fluorescence Hybridization: Visualization of Individual Gene Transcription and RNA Splicing: A Thesis

Xing, Yigong P. 01 April 1993 (has links)
The overall objective of this study has been to address some of the longstanding questions concerning functional organization of the interphase nucleus. This was achieved by using recently developed high-resolution fluorescence in situ hybridization techniques for a precise localization of specific DNA and RNA sequences in conjunction with immunocytochemistry and biochemical fractionation. This study is based on the philosophy that new insights may be gained by an approach that attempts to interrelate genomic organization, spatial arrangement of RNA metabolism, and nuclear substructure within the mammalian cell nucleus. The nuclear distribution of an exogenous, viral RNA (Epstein-Barr Virus, EBV) within nuclear matrix preparations was studied by developing an approach which couples in situhybridization with biochemical fractionation procedures. EBV RNA molecules accumulate in highly localized foci or elongated tracks within the nucleus of lymphoma cells. These RNA tracks were retained with spatial and quantitative fidelity in nuclear matrix preparations even after biochemical fractionation which removes 95% of cellular protein, DNA, and phospholipid. This provided direct evidence that the primary transcripts are localized via their binding to, or comprising part of, a non-chromatin nuclear substructure. Then the nuclear distribution of RNA from an endogenous gene, fibronectin, was investigated using fluorescence techniques modified for more sensitive detection of endogenous RNAs within nuclear morphology. A series of in situhybridization experiments were performed using different combinations of intron, cDNA, and genomic probes for RNA/RNA or RNA/DNA analysis in intact cells. Fibronectin RNAs were highly localized in the nucleus, forming foci or tracks. Both intron and exon sequences were highly concentrated at the same site within the nucleus, indicating the presence of primary unspliced transcripts. Double-color hybridization using a nontranscribed 5' flanking sequence probe and a genomic DNA probe showed that the gene and RNA track for fibronectin were spatially overlapped, with the gene consistently towards one end of the track. These results provided evidence that the accumulation of RNA molecules occurs directly at or near the site of transcription, and further indicated a structural polarity to the RNA track formation with the gene towards one end. It was further discovered that within a single cell, cDNA probes produced longer tracks than those formed with intron probes, i.e. intron signals were generally confined to a smaller part of the track than the exon signals, indicating that splicing occurs within the RNA track. Additional experiments using poly(A) RNA hybridization or anti-SC-35 antibody staining combined with fibronectin RNA hybridization have shown that the fibronectin tracks were associated with recently discovered transcript domains enriched in poly(A) RNA and splicing factors. To further determine whether other specific genes and RNAs are functionally organized within the nucleus, the nuclear distribution of several active or inactive genes was analyzed in terms of their spatial relationship to transcript domains. The results indicated that in addition to fibronectin, the genes or their primary transcripts from two other active genes, collagen and actin, were also closely associated with the domains. For both of these, over 90% of the gene/RNA sites were either overlapping or directly contacting the domains. In contrast. for two inactive genes, cardiac myosin heavy chain and neurotensin, it was found that both genes were separated from the domains in the majority of nuclei. Histone genes, which have several unique features, showed a relatively complex result with about half of the gene signals extremely close to the domains. Therefore, three actively expressed genes were demonstrated to be tightly associated with the domains and, moreover, their RNAs showed distinct and characteristic spatial relationships with the domains. In contrast, two inactive genes were not associated with the domains. One potential implication of these finding is that active genes may be preferentially localized in and around these transcript domains. The nuclear localization of another RNA, XIST, standing for X-inactivation specific transcript, was studied because of its potentially unique biological role. XIST is the only gene which is known to be expressed from the inactive human X chromosome but not from the active X chromosome, and was believed to be important in X inactivation. Using fluorescence in situhybridization, it was found that XIST RNA was highly localized within the nucleus and always completely overlapped the Barr body which is the condensed, inactive X chromosome. The different fine distribution pattern of XIST RNA within the nucleus as compared to other protein coding RNAs suggested a unique function for this RNA, possibly involving a structural role in inactivating the X chromosome. The final area of my thesis research was to study and acquire expertise in the applications of fluorescence in situ hybridization in gene mapping and cancer genetics. A retinoblastoma (RB)-related putative tumor suppressor gene, p107, was mapped to human chromosome 20 in band q11.2. Localization of p107 to 20q11.2 was of particular interest because of the correlation of breakpoints in this area with specific myeloid disorders such as acute nonlymphocytic leukemia and myelodysplastic syndrome. Other applications of in situ hybridization including the search for unknown genes at a known chromosomal breakpoint, detection of deletions, translocations or other chromosomal rearrangements associated with specific tumors were also explored and reviewed.
547

Determining the Fate of Hybridized Genomes in the Allopolyploid Brassica napus

Wang, Tina Y 01 July 2010 (has links)
Polyploidy is widely acknowledged as a widespread mechanism in the evolution and speciation of the majority of flowering plants. Allopolyploid forms through interspecific hybridization and whole genome duplication. While allopolyploids may display increased vigor relative to their progenitors, they can also face challenges to fertility following hybridization. Genetic changes in allopolyploids result from recombination between the hybridized subgenomes, which can influence phenotype and ultimately determine fitness of future generations. To study dynamic changes that follow allopolyploid formation, Brassica napus lineages were derived by hybridizing Brassica oleracea and Brassica rapa. Two lineages of B. napus were analyzed for genetic and phenotypic changes in the S2, S7, and S12 generations. Although these lineages were genetically identical at the time of hybridization, divergence was apparent by the S2 generation. There was a significant increase in sequence loss across generations within both lineages. Four of six generations from both lineages displayed no significant differences to each other in sequence loss relative to the parental generation. In both lineages, there was a bias towards losing sequences from the B. olereacea subgenome. Some individual plants showed novel phenotypes; however, there was no correlation between the examined genetic changes and selected phenotypes.
548

Pétrogenèse des carbonatites et magmas alcalins protérozoïques d’Ihouhaouene : terrane de l’In Ouzzal, Hoggar occidental, Algérie / Petrogenesis of Proterozoic carbonatites and alkaline magmas from Ihouhaouene : In Ouzzal terrane, Western Hoggar, Algeria

Djeddi, Asma 02 July 2019 (has links)
Le craton archéen de l’In Ouzzal représente une succession d'événements intrusifs et métamorphiques depuis l’Eburnéen qui en font un marqueur important des processus géodynamiques à travers les temps géologiques. La région d’Ihouhaouene située au N-W du terrane de l’In Ouzzal en Algérie est unique de par la présence d’intrusions protérozoïques de carbonatites associées à des roches alcalines saturées. Ces carbonatites intracontinentales comptent parmi les plus anciennes et inhabituelles de par leurs diversités et la présence de minéraux à terres rares. Les carbonatites sont pegmatitiques ou bréchiques avec des fragments de syénite. Elles sont des calciocarbonatites composées de calcite (>50 vol.%), apatite, clinopyroxène et wollastonite et sont associées à des syénites rouges ou blanches présentes sous forme massive. Les syénites sont composées d’alternance de niveaux clairs de feldspaths alcalins rouges ou de wollastonites associées aux feldspaths blancs et de niveaux sombres d’apatites et de clinopyroxènes. Les carbonatites et syénites forment une suite cogénétique caractérisée par une augmentation en SiO2 et une diminution en CaO et CO2. Les carbonatites ont des compositions en silice comprises entre 5 et 35 pds.%, 28 et 53 pds.% CaO et 11 à 36 pds.% CO2. Les syénites montrent une forte teneur en K2O (12 pds.%) et des teneurs très faibles en Na2O (1 pds.%). Les carbonatites et syénites sont riches en éléments incompatibles avec des teneurs en REE supérieures à 7000 fois les chondrites et 1000 fois les chondrites dans les syénites, respectivement, et de fortes teneurs en U, Sr et Th. Les éléments en trace dans les minéraux magmatiques (apatite et pyroxène) mettent en évidence des processus complexes à l’origine de ces roches impliquant plusieurs étapes de cristallisation fractionnée et d’immiscibilité à partir d’un magma mélilititique riche en CO2. Les minéraux des carbonatites riches en silice et des syénites blanches ont des signatures géochimiques similaires et se caractérisent par des rapports élevés en Nb/Ta typiques de magmas riches en carbonate par immiscibilité. Les syénites rouges ont des caractéristiques de liquides silicatés évolués par différentiation. Les minéraux des carbonatites pauvres en silice ont des rapports Nb/Ta très variables, sub-chondritiques (<10), indiquant une cristallisation à partir de liquides très évolués et la présence de magmas carbonatitiques tardifs. Les apatites, en particuliers, enregistrent divers épisodes magmatiques et également supergènes. Elles présentent dans certaines roches une redistribution et un enrichissement en terres rares variables qui se caractérisent par des exsolutions de britholite dans les carbonatites riches en silice et monazite dans les carbonatites pauvres en silice. Ces exsolutions traduisent des rééquilibrations locales sub-solidus avec des fluides tardi-magmatiques de composition riche en Cl-Th-REE pour l’exsolution de la britholite et S-Ca-P-CO2 pour les inclusions de monazite. L’apatite et le zircon présents dans ces roches alcalines et carbonatites, ont permis de déterminer l’âge de mise en place du complexe magmatique de Ihouahouene à 2100 Ma syn-métamorphique et de confirmer l’âge panafricain de son exhumation. L’étude pétrologique, géochimique et géochronologique des carbonatites et syénites d’Ihouhaouene a permis de mettre en évidence l’origine magmatique de ces roches et de définir les interactions fluides-roches supergènes à l’origine des enrichissements en REE. Les carbonatites et syénites d’Ihouahouene proviennent d’un faible taux de fusion partielle d’un manteau Précambrien riche en CO2. Plusieurs étapes de cristallisation fractionnée et d'immiscibilité ont permis la genèse de ces roches hybrides, piégées le long de grandes zones de cisaillement durant la période de transition Archéen /Eburnéen dans un régime extensif à l’In Ouzzal caractérisé par un environnement granulitique d’ultra-haute-température. / The In Ouzzal Archaean craton represents a succession of intrusive and metamorphic events since Eburnean, and an important marker of geodynamic processes through geological time. The Ihouhaouene area located in the N-W of In Ouzzal terrane in Algeria is unique by the presence of Proterozoic carbonatite intrusions associated with silica-saturated alkaline rocks. These intracontinental carbonatites are among the oldest and exceptional because of their diversity and the presence of unusual rare earth minerals. Carbonatites are pegmatitic or brecciated with fragments of syenite. They are calciocarbonatites with calcite (> 50 vol.%), apatite, clinopyroxene and wollastonite and are associated with red or white syenites in massive outcrops. Syenites are composed of alternating light levels of red alkaline feldspar or wollastonite associated with white feldspar and dark levels of apatite and clinopyroxene. Carbonatites and syenites form a cogenetic suite characterized by an increase in silica and decrease in calcium and CO2 content. The carbonatites have silica content ranging from 5 to 35 wt.%, 28 to 53 wt.% CaO, and 11 to 36 wt.% CO2. Syenites have high K2O (12 wt.%) and low Na2O content (1 wt.%). Carbonatites and syenites have high incompatible element concentrations with high REE content (7000*chondrites and 1000*chondrites, respectively) and high U, Pb, Sr and Th content. Trace elements (eg. Rare Earths, Nb-Ta, Zr-Hf) in magmatic minerals (apatite-pyroxene) of carbonatites and syenites reveal complex magmatic processes at the origin of these rocks involving several stages of fractional crystallization and immiscibility from a CO2-rich melilititic magma. Silica-rich carbonatites and white syenites are characterized by high Nb/Ta, Y/Zr and Rb/Sr ratios, typical of carbonate-rich magmas by immiscibility. The red syenites have characteristics of immiscible differentiated silicate melt. Silica-poor carbonatite minerals have variable subchondritic Nb/Ta (<10) indicating crystallization from highly evolved liquids and the presence of late carbonatitic magmas. Apatites, in particular, record various magmatic and supergene processes. They present, in some rocks, redistribution and enrichment in rare earth elements, which are characterized by exsolutions of britholite in silica-rich carbonatites and monazite-quartz-calcite inclusions in silica-poor carbonatites. These minerals reflect local sub-solidus re-equilibration with late-magmatic fluids rich in Cl-Th-REE for the exsolution of britholite and S-Ca-P-CO2 for monazite inclusions. The apatite and zircon present in these alkaline and carbonatite rocks, allow determination of the syn-metamorphic crystallization age of the Ihouahouene magmatic complex at 2100 Ma and confirm the pan-African age of its exhumation. The petrological, geochemical and geochronological study of Ihouhaouene carbonatites and syenites highlights the magmatic origin of these rocks and constrains the fluid-rock interactions at sub-solidus conditions leading to REE-enrichment. The carbonatites and syenites result from a low partial melting rate of a CO2-rich Precambrian mantle. Several fractional crystallization and immiscibility stages allowed the genesis of these hybrid magmas, trapped along large shear-zones during the Archean/Eburnean transition period in the In Ouzzal terrane, characterized by extensive deformation in ultra-high-temperature granulitic environment.
549

Zdroje variability v Sorbus aria agg. / Sources of Sorbus aria agg. variation

Bílá, Jana January 2015 (has links)
The main drivers of microevolution in the genus Sorbus are interspecific hybridisation and polyploidy. The fate of new hybrid and polyploid taxa is determined by their mode of reproduction. Especially apomixis could be very advantageous for these new taxa. The S. aria agg. (subg. Aria) plays an important role within the genus since its members are involved in all hybridisation events and thereby is responsible for the substantial part of variation of the genus. Flow cytometry, molecular markers and multivariate morphological analyses were employed to evaluate the processes generating the variability in the S. aria group. Three ploidy levels were detected among species from subg. Aria in the Czech Republic. All of them could be found in the South Moravia, whereas only tetraploids occur in the Bohemia region. Moreover, most of the Czech taxa (5 out of 7) grow also only in the South Moravia which is therefore considered as a centre of diversity of the genus Sorbus in the Czech Republic. Flow cytometry seed screen revealed 7 modes of reproduction among the individuals from S. aria agg. A wide range of sexual and apomictic types of reproduction including reduced and unreduced gametes was detected. All of the diploid individuals are completely sexual. Among polyploid taxa, most of the species are...
550

Vliv interakce lokálních a mezinárodních aktérů na hybridizaci míru v průběhu a po skončení procesu post-konfliktního peacebuildingu / The Impact of Interaction between Local and International Actors on Peace Hybridization during and after the Post-conflict Peace-building Process

Knapová, Martina January 2016 (has links)
The thesis based on analysis of international community peacebuilding policy and consequent reaction by local actors assesses the influence of this interaction onto the liberal peace and changes in missions' operation. The extent of local ownership and the real agency of local actors is then dependent on the time of mission occurrence, power related interests of international community and the force and accessibility of structures that the international community tries to influence. Key words: peacebuilding, hybridization, local ownership, Bosnia and Herzegovina, Afghanistan, Sierra Leone

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