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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.
51

Hnízdní chování a populační genetika samotářských včel (Hymenoptera: Anthophila) / Nesting behaviour and population genetics of solitary bees (Hymenoptera: Anthophila)

Černá, Kateřina January 2013 (has links)
My thesis is focused on nesting behaviour and population genetics of solitary bees. These two topics, although seemingly unrelated, bring much new information and thus contribute to the better understanding of solitary bee biology that is still insufficiently known. Although the solitary behaviour represents the necessary original state for the evolution of higher sociality or obligate cleptoparasitism, its role is largely unappreciated. Furthermore, intraspecific cleptoparasitism, which is an alternative and facultative nesting strategy in bees, is a probable antecedent state of obligate cleptoparasitism. Although the obligate cleptoparasitism is a very common strategy in solitary bees, the information about the frequency and the occurrence of intraspecific cleptoparasitism in solitary bees is rare. We studied the nesting behaviour of solitary bees to detect different behavioural patterns that could serve as preadaptations to sociality or cleptoparasitic behaviour and we also focused on the detection and description of intraspecific cleptoparasitism in solitary bees. We chose four model solitary species for these studies - Andrena vaga (Andrenidae), Anthophora plumipes (Apidae), Colletes cunnicularius (Colletidae) and Osmia rufa (Megachilidae). We described the behaviour of Andrena vaga at the...
52

Genetické pozadí obezity a její léčba bariatrickou chirurgií / The genetic background of obesity and its treatment with bariatric surgery

Lischková, Olga January 2016 (has links)
Obesity is a frequent metabolic disease that causes many other health and socioeconomic complications. Obesity arises due to excessive energy intake and decrease in energy expenditure, which is a conseqence of contemporary lifestyle. Moreover, obesity has a strong genetic component. Common obesity is polygenic, multifactorial disease, in which individual genes interact with each other and with environmental factors. Genome-wide association studies, conducted between 2006-09, led to the discovery of dozens of gene loci that predispose individuals to obesity. The strongest signals were registered for polymorphisms in FTO (fat mass and obesity-associated) and near a gene MC4R (melanocortin 4 receptor). However, the contributions of these variations on the phenotype of obesity are very small, therefore, it is necessary to validate the results of such robust studies. It is very important to uncover the effects of genetic variants for understanding the molecular mechanisms of energy metabolism. The studies presented in this thesis refer about the impact of polymorphisms in selected genes on anthropometric and metabolic parameters of the patients of the Institute of Endocrinology and of healthy volunteers who underwent functional tests. Our cohort includes a representative sample of Czech children (COPAT...
53

Jerubės (Tetrastes bonasia) populiacijų genetinės struktūros įvertinimas lietuvoje, naudojant mikrosatelitų molekulinius žymenis / Evaluation of genetic variation in a Hazel Grouse (Tetrastes bonasia) population in Lithuania using microsatellite markers

Tomaitė, Gintarė 13 August 2012 (has links)
Šiame darbe buvo tiriamas Lietuvoje gyvenančių jerubių genetinis variabilumas panaudojant mikrosatelitinių pradmenų analizės metodus. Pavyzdžiai buvo surinkti iš Rietavo savivaldybėje, Ukmergės, Trakų, Vilniaus, Šakių ir Telšių rajonuose esančių miškų. DNR buvo išskiriama iš neinvaziniu būdu surinktų pavyzdžių, iškritusių plunksnų bei surinktų ekskrementų. Kadangi specialių mikrosatelitinių pradmenų jerubių rūšiai dar nėra sukurta, šiame darbe buvo panaudotos trys žvyrėms (Lagopus lagopus) specifiški mikrosatelitinių lokusų pagausinimui skirti pradmenys. Buvo apskaičiuoti alelių, genotipų ir heterozigotiškumo dažniai, ir individai iš Ukmergės MU pasižymėjo žemu alelių dažniu ir aukštu homozigotų dažniu. Mitochondrinės DNR analizė parodė, kad tarp 12 Lietuvos populiacijai priklausančių jerubių sekų, net 8 buvo skirtingos ir dėl to priskirtinos 8 skirtingiems haplotipais. Mitochondrinės DNR sekų filogenetiniai ryšiai parodė, kad Lietuvos jerubių populiacijoje aptikti haplotipai formuoja dvi filogenetiškai tolimas šakas, tuo tarpu Lenkijos haplotipų įvairovė gerokai didesnė. Tikėtina, kad šiuos skirtumus labiausiai įtakoja nevienodi lyginamų imčių dydžiai. / Non-invasively collected samples of feathers and faeces of Hazel Grouse (Tetrastes bonasia) were collected in different parts of Lithuania and covered several local populations of Rietavas, Ukmergė, Trakai, Vilnius, Šakiai and Telšiai districts. Three primer pairs of microsatellite loci, designed for taxonomically related Red Grouse (Lagopus lagopus scoticus), were used to verify their suitability for evaluation of genetic structure. Allele and genotype frequencies as well as heterozygosity were calculated and individuals from Ukmergė showed low frequency of allele, and high in homozigosity. Mitochondrial DNA analysis showed that in 12 sequences from Lithuanian population, 8 of them were different and could be assigned to 8 different haplotypes. Neighbour joining tree showed that haplotypes in Lithuanian population forms two branches with high distance. While variability of Poland haplotypes, obtained from Gene Bank was bigger. That could be affected by different compared samples sizes.
54

Šunų kluba sąnario displazijos genetiniai aspektai / Canine hip dysplasia genetic aspects

Kliščenko, Aleksandra 05 March 2014 (has links)
Santrauka Baigiamojo darbo tema Šunų klubo sąnario displazija genetiniai aspektai Baigiamasis darbas atliktas 2012 - 2014 metais Biologiniu sistemų ir genetinių tyrimų institute, K. Janušausko gyvūnų genetikos laboratorijoje. Baigiamojo darbo kiekis 53 puslapių, 15 paveikslėlių , 8 lentelės. Darbo objektas ir uždaviniai. Išanalizuoti šunų klubo sąnario displazijos paveldimumą . Uždaviniai: išanalizuoti literatūrą apie šunų klubo sąnario displazijos genetinius aspektus , klinikinius požymius , diagnostikos ir gydymo metodus , priežastis, paveldėjimą , įvairių veislių šunų displazijos paplitimą, įvertinti genetinių veiksnių - veislės, amžiaus ir lyties įtaką - šunų klubo sąnario displazijos atsiradimui. Mokslinių tyrimų metodologija. Surinkti ir išanalizuoti literatūrą apie šunų klubo sąnario displazijos paplitimą " Jokovo veterinarijos centras" smulkių gyvūnų klinikoje. Rezultatai ir išvados. 2009 - 2013 metais buvo ištirta 638 šunų, iš kurių 169 nustatyta KDS, tai sudaro 26,5% visų ištirtų šunų. Dažniausiai KDS sirgo Amerikiečių stafordšyro terjerai (66,6%), Bordo dogai (66,6 %), Kaukazo aviganiai (57,1%), Anatolijos Karabašai (50%), Korsikos šuo (50%), Leonbergeriai (50%) ir Rytų Europos aviganiai (50%). Rečiausiai sirgo - Sibiro haskiai (7,1%), Amerikiečių akita (10%), samojedai (10%) ir dobermanai (11,1%). Dažniau KSD pasireikšdavo patelėms (31,5%) nei patinams (26,3%). Pagal pasaulinės organizacijos OFA duomenis, atliktus 1974 - 2012 metais Bordo dogai, senbernarai ir... [toliau žr. visą tekstą] / Summary Topic of Final study thesis Canine hip dysplasia genetic aspects Final work accomplished in the year 2012 – 2014 in Institute of Biology Systems and Genetics, K. Janušauskas Laboratory of Animal Genetics. Volume of Final work 53 page original, 15 pictures, 8 tables. Object and tasks of work. Analyse heredity of canine hip dysplasia. Tasks: analyse literature about canine hip dysplasia genetic aspects, clinical signs, diagnosis and treatment methods, causes, inheritances, prevalence of dysplasia in different breeds of dogs; evaluate influence of genetic factors - breed, age and sex – to occurrence of canine hip dysplasia. Research methodology. Gathering and analysing literature about canine hip dysplasia prevalence in “Jokov veterinary center”. Results and conclusions. During 2009 – 2013 years were examined 638 dogs for hip dysplasia manifestation, of which 169 established HD, accounting for 26,5% of the tested dogs. Mostly HD had the American Staffordshire Terrier (66.6%) Dogue de Bordeaux (66.6%), Caucasian shepherd (57.1%), the Anatolian Shepherd Dog (50%), the Corsican dog (50%), Leonberger (50%) and East European shepherd (50%). Least amount of HD were in - Siberian Huskies (7.1%), American akita (10%), Samoyed (10%) and a Dobermans (11.1%). More often CHD were fixed in bitches (31,5%) than in male dogs (26,3%). Up to 18 months age, hip dysplasia established 26,6%, and over 18 months – 31,8%. According to the global organization of OPA made researches in 1974 - 2... [to full text]
55

Population biology of the pine needle pathogen Lecanosticta acicola (Thüm.) Syd. (Capnodiales, Ascomycota)

Janoušek, Josef January 2015 (has links)
Lecanosticta acicola is a heterothallic ascomycete that causes brown spot needle blight (BSNB) on native and non-native Pinus spp. in many regions of the world. The aim of this thesis was to elucidate the origin of L. acicola populations in Europe and consider the reproductive mode of the pathogen in affected areas. In order to study the population genetics of L. acicola, eleven polymorphic microsatellite markers were developed. In addition, mating type markers that amplify both mating type idiomorphs (MAT1-1 and MAT1-2) were designed and the protocols for their applications were optimised. Collections of diseased material were obtained from 17 host species in Asia, Europe and America. In total, 201 isolates from diseased pine needles were obtained. All isolates were screened with the microsatellite markers and the mating type idiomorph determined with the mating type markers. For 87 individuals, part of the Translation Elongation Factor 1-alfa gene was sequenced. The isolates from Central America were unique, highly diverse and most likely represent a new cryptic species. The isolates from East Asia formed a discrete group. Two distinct populations were identified in both North America and Europe. Approximate Bayesian Computation analyses strongly suggest independent introductions of two populations from North America into Europe. Microsatellite data and mating type distributions showed the presence of sexual reproduction in North America and in Europe. Results from this thesis have showed that European populations of L. acicola originate from North America. This is the first study of L. acicola populations on a global scale.
56

Genetická analýza vybrané dědičné choroby u psů

VOLNÁ, Jitka January 2016 (has links)
In my thesis I concentrated on an analysis of biological samples of 60 dogs, which manifested epilepsy. The aim was to find out the relation between genotype of the selected locus and the occurrence of epilepsy. Based on the results of the analysis, I assessed, whether there is a demonstrable relation between the occurrence of epilepsy and genotype in a particular locus. According to the results, no influence of genotype on the age of first epileptic seizure was proved.
57

Využití bílkovinných signálních genů pro hodnocení účinnosti gametocidu GENESIS u pšeniceTriticum aestivum L./

Vyhnánek, Tomáš January 2001 (has links)
No description available.
58

Transgenoze hrachu setého (Pisum sativum L.) : využitelné metody přenosu genů pomocí agrobacterium tumefaciens

Krejčí, Petra January 2003 (has links)
No description available.
59

Genetická variabilita v populacích chrastice rákosovité (Phalaris arundinacea L). / Genetic variation in populations of reed canarygrass, \kur{Phalaris arundinacea} L.

KÁVOVÁ, Tereza January 2013 (has links)
The spread of invasive plant species in natural habitats has become a worldwide problem with negative environmental and economic impacts. An increasing number of invasive organisms are responsible for adverse environmental and economic impacts worldwide, including species extinction, crop failures, reduced water supply, and damage to industrial infrastructures (KERCHER et al., 2007). Phalaris arundinacea L. is widespread throughout the world, except Antarctica and Greenland. Center of diversity of this genus is in the Mediterranean. Members of the genus Phalaris occurs in moist habitats from lower to alpine altitudes (ANDERSON, 1997). Phalaris has a plethora of uses. Its most frequent use is as the root wastewater treatment plants. Phalaris grown as feed for livestock and is also used as an ornamental grass. Phalaris have recently received a lot of attention as a new biomass source for the production of renewable energy in USA. In recent years there has been a massive spread of P. arundinacea across North America (currently occurs in 43 states) and Canada (ZEDLER & KERCHER, 2004). Phalaris represents a significant threat to its original wetland vegetation and is classified as a harmful agens in nine state of U.S. states (LAVERGNE & MOLOFSKY, 2004). It is believed that these aggressive population have European origin.
60

Populačně genetická struktura pstruha obecného jako základ úspěšného obhospodařování lososových vod ve střední Evropě

KOHOUT, Jan January 2013 (has links)
The genetic structure of 25 wild populations and five hatchery stocks from Czech Republic and Slovakia were analysed using mitochondrial (control region) and nuclear DNA (microsatellites, LDH-C1*) markers to elucidate the impact of stocking on central European populations of brown trout and to outline further management strategies. It seems that stocking practices have caused massive hybridisation between the Atlantic and Danube brown trout populations in the middle Danube basin and have led to a loss of among-population genetic variability in Slovakia and Moravia. Certain effect of stocking was detected also in the upper Danube, Vistula, Oder and Elbe River basins. However, the populations from the Elbe River basin keep certain level of among-population variability and seem to be less affected by stocking in comparison with the Danube River basin populations. There are some indications of late or post-Pleistocene penetration of the Atlantic basin trout to the Danube River basin. However, it is not clear to which extent the natural contact participated to the present distribution of Atlantic haplotypes and alleles in the Danube River basin. Samples from lower parts of the Danube River basin were therefore analysed using the same mitochondrial and microsatellite markers. Samples from Aegean Sea basin were included in order to reveal genetic variability of eastern Balkan populations and to estimate an impact of stocking in this area. Very low levels of introgression from Atlantic and other non-indigenous trout were found in the eastern Balkan populations. The genetic differentiation among the populations is substantially higher in this area compared to the central European populations. The populations in headwaters of the Otava River (Elbe River basin) were analysed using microsatellites in order to reveal origin of these populations and evaluate the current management strategies of brown trout in Šumava National Park and Protected Landscape Area. The analysed populations were substantially differentiated from the remaining Elbe River basin populations and there was also certain level of genetic structure within trout from the headwaters of the Otava River associated with isolation by a migration barrier and geographic distance. However, stocking with hatchery trout also contributed to the pattern of genetic variability. The population of Borová Lada hatchery, which is used for stocking in Šumava exhibited higher genetic variability compared to the wild populations and it seems to be of heterogeneous origin. Comparisons of the analysed populations with populations from other areas and results from other studies indicated that mtDNA haplotypes from the lower Danube River and southern Black Sea basins differ considerably from a subclade of the Danubian lineage consisting of haplotypes found so far in the most of the Danube River basin and in the Caspian and Aral Sea basins. The results thus evidence a complex evolutionary history of brown trout in the southern and western parts of the Black Sea basin.

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