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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.
61

Molekulární aspekty mezidruhové hybridizace jeseterovitých ryb ve vztahu k polyploidii a in situ konzervaci / Molecular aspects of interspecific hybridization of sturgeons related to polyploidy and in situ conservation

HAVELKA, Miloš January 2013 (has links)
Sturgeons (Chondrostei: Acipenseriformes) display markedly disjunct distributions with a wide occurrence in the northern hemisphere. Their unique benthic specializations, conserved morphology, evolutionary age, the variation in their basic diadromous life history, and the large public interest due to their near extinction or critically endangered status make sturgeons and paddlefishes one of the most interesting group of vertebrates. In addition to that, ploidy diversity of Acipenseriformes possessing three ploidy groups having ~ 120 chromosomes, ~ 240 ? 270 chromosomes and ~ 360 chromosomes provides unique model for investigation of evolutionary processes which were going through the genome duplication events. Sturgeons are also notoriously known for their strong propensity to interspecific and intergeneric hybridization which can result in hybrids with various ploidy levels. All these facts make sturgeon genetics and cytogenetics a thriving but also complicated area for research. In the present work, the role of genome duplication and functional reduction evens in evolution of sturgeon species as well as sturgeons? ploidy levels and ploidy relationships among Acipenseriformes were investigated using molecular markers. In addition to that, clarification of origin of abnormal ploidy levels and observation of segregation pattern of microsatellite alleles in the course of hybridization of polyploid sturgeon species were included into this study. With regard to the all considerations and observations provided by this study we concluded that evolution of sturgeon species is still widely dynamic and ongoing process which might goes through the allopolyplodization as well as autopolyplidization events.
62

Úloha polymorfních markerů DNA v identifikaci osob a určování vybraných fenotypových znaků. / Role of polymorphic DNA markers in personal identification and determination of selected phenotypic traits

Zidkova, Anastassiya January 2013 (has links)
Nowadays intensive research is conducted for application of genetic polymorphisms for degraded samples analysis, identification and kinship determination. Another area of research in forensic genetics is biogeographical and phenotypic traits (eye, hair and skin color) determination. First part of presented work dealt with population study on the Czech popu- lation using Investigator DIPplex (QIAGEN, Germany) marker set containing 30 autosomal insertion-deletion polymorphisms. Power of Discrimination (PD), which is the probability of random selection of two persons with different genotypes, was 99.9999999999% for the whole marker set. This part of study concluded that ana- lyzed marker set is suitable as an additional marker panel for identification and kinship determination in the Czech Republic. Second part of the presented study was devoted to population research of Cen- tral Croatia using Mentype Argus X-8 kit (QIAGEN, Germany) containing 8 short tandem repeat polymorhisms located on X choromosomes (X-STR) divided into 4 linkage groups. PD for the whole kit reached 99.9999% and 99.99999999% for males and females, respectively. This kit could be used in Central Croatian population for kinship analysis and for identification as an additional marker panel. The next part of the presented study was the...
63

Genetická variabilita a diferenciace eurasijských populací rákosníka obecného\kur{(Acrocephalus scirpaceus)} / Genetic variation and differentiation of the Eurasian reed warbler \kur{(Acrocephalus scirpaceus)}

FAINOVÁ, Drahomíra January 2008 (has links)
Eurasian Reed Warbler (Acrocephalus scirpaceus) is a long-distance migrant wintering in sub-Saharan Africa and breeding in reedbeds of the Western Palaearctic. European populations migrate in two main directions (SW and SE). Though there is little morphological variation across the breeding range, Asian populations are traditionally separated from the nominate subspecies as the subspecies fuscus. My aim was to explore genetic differentiation among Eurasian Reed Warbler populations in respect to the factors which may have influenced the genetic diversity and divergence of the populations, such as a migratory divide, high migratory connectivity or isolation by distance. I used samples of 495 individuals from 36 populations across the breeding range using microsatellites. Pairwaise fixation indexes FST showed significant differences among populations from the Iberian peninsula, Finland and the Middle East and the rest of populations. Exact tests of differentiation did not confirm non-random distribution between pairs of populations. Overall FST was statistical significant but very small (FST = 0,018). Analysis of molecular variance (AMOVA) revealed that 98% of variation was ascribable to variability of allele frequencies within populations. On the other hand, differences between populations contributed to overall variation with only 2%. Isolation by distance showed only weak relationship between geographical and genetic distances. Main analysis using Bayesian clustering approach implemented in software Structure 2.2. detected no genetic structure of population. Sampled Eurasian Reed Warbler populations seem to form one genetic population. Relatively low genetic diversification indicates large dispersal potential of the studied Reed Warbler populations, when gene flow successfully counters differentiation of population irrespective of large breeding area and high migrate connectivity between breeding and wintering area.
64

Diverzita sekvencí mtDNA a genetická struktura východoafrického sahelu / Sequence diversity of mtDNA and genetic structure of eastern part of the African Sahel

Tlačbabová, Klára January 2017 (has links)
Eastern part of the African Sahel, connecting sub-Saharan Africa with North and East Africa, play an important role as a bidirectional corridor for vertically and horizontally migrations of populations. It is the strategic region to study human genetic diversity due to the presence of ethnically, linguistically, culturally and geographically diversity. This work is focused on the analysis of HVS-I and HVS-II segments of mtDNA. The work provides new information about genetic structure and migration activity of this region by analysis twelve populations belonging to three African linguistic families and different subsistent strategies. Analysis of mtDNA revealed the higher diversity of the populations of east Sudan and Horn of Africa, which is connected with the spreading of populations along the Nile River. It seems, that in this region linguistic factors have bigger impact on genetic diversity then the geografic ones. The opposite situation is observed in populations of Chad, where populations with similiar geografic location and different linguistic affilation revealed low genetic differentiation. The intra-population analysis shows the significant influence of genetic drift on the pastoralists living on the Red Sea Coast - Beja and Rashaida. In Beja is probably due to decrease of size of...
65

Molekularni i morfološki diverzitet populacija gljiva rodova Marasmius Fr. 1836, Mycetinis Earle 1909 i Gymnopus (Pers.) Gray 1821 u šumskim ekosistemima Nacionalnih parkova Srbije i Crne Gore / Molecular and morphological diversity of fungal populations of genera Marasmius Fr. 1836, Micetinis Earle 1909 and Gymnopus(Pers.) Grey 1821 in forest ecosystems of National parks of Serbia and Montenegro

Bošković Eleonora 30 September 2019 (has links)
<p>Ciljevi&nbsp; istraživanje&nbsp; ove&nbsp; doktorske&nbsp; disertacije&nbsp; bili&nbsp; su&nbsp; određivanje makroskopskih&nbsp; i&nbsp; mikroskopskih&nbsp; karakteristika&nbsp; plodonosnih&nbsp; tela analiziranih vrsta roda <em>Marasmius, Gymnopus </em>i <em>Mycetinis i</em> njhove varijabilnosti&nbsp; između&nbsp; populacija,&nbsp; određivanje&nbsp; uticaja&nbsp; klimatskih faktora&nbsp; na&nbsp; varijabilnost&nbsp; morfolo&scaron;kih&nbsp; karaktera,&nbsp; određivanje brojnosti&nbsp; i&nbsp; rasprostranjenja&nbsp; jedinki&nbsp; na&nbsp; odabranim&nbsp; lokalitetima&nbsp; u okviru&nbsp; Nacionalnih parkova Srbije i Crne Gore&nbsp; (Kopaonik, Stara planina,&nbsp; Biogradska&nbsp; gora)&nbsp; koristeći&nbsp; ISSR&nbsp; metodu,&nbsp; kao&nbsp; i određivanje osnovnih populaciono-genetičkih parametara i analiza<br />filogenetskih odnosa u okviru roda <em>Marasmius</em>. Kod vrste&nbsp;<em> M. alliaceus</em>&nbsp; utvrđeno je da se na osnovu morfolo&scaron;kih karaktera&nbsp; populacija&nbsp; sa&nbsp; Stare&nbsp; planine&nbsp; delimično&nbsp; izdvaja,&nbsp; dok&nbsp; je kod&nbsp; populacije&nbsp; Biogradska&nbsp; gora&nbsp; uočena&nbsp; najveća&nbsp; heterogenost&nbsp; u ispitivanim&nbsp; karakterima.&nbsp; Kod&nbsp; vrste&nbsp; <em>G. androsaceus</em>&nbsp; uočeno&nbsp; je&nbsp; da nema jasnog izdvajanja populacija, odnosno ispitivane populacije su pokazale heterogenost u ispitivanim morfolo&scaron;kim karakterima. Uočena&nbsp; je&nbsp; statistički&nbsp; značajna&nbsp; (p&nbsp; &lt;&nbsp; 0.05)&nbsp; korelacija&nbsp; između morfolo&scaron;kih karaktera i faktora sredine kod obe analizirane vrst<em>e M. alliaceus</em> i <em>G</em>. <em>androsaceus.</em> Određivanjem&nbsp; broja&nbsp; i&nbsp; veličine&nbsp; geneta&nbsp; ISSR&nbsp; metodom&nbsp; u populacijama&nbsp; vrsta<em>&nbsp; M.&nbsp; alliaceus,&nbsp; M.&nbsp; rotula&nbsp; i&nbsp; G.&nbsp; androsaceus</em> utvrđeno&nbsp; je&nbsp; da&nbsp; ove&nbsp; vrste&nbsp; formiraju&nbsp; relativno&nbsp; male&nbsp; genete&nbsp; (od nekoliko desetina centimetara do 15m) koji se nalaze u relativnoj blizini jedni od drugih (nekoliko metara). Određivanjem&nbsp; parametara&nbsp; molekularnog&nbsp; diverziteta&nbsp; (AMOVA, Fst) kod populacija vrsta&nbsp;<em> M. alliaceus&nbsp; i&nbsp; G. androsaceus</em> utvrđeno je&nbsp; da&nbsp; su&nbsp; populacije&nbsp; obe&nbsp; ispitivane&nbsp; vrste&nbsp; značajno&nbsp; genetički<br />diferencirane (Fst vrednosti veće od 0.25) odnosno da postoji mali protok gena između njih.Filogenetska analiza ITS + LSU i ITS + LSU + EF-1ɑ sekvenci u ovom&nbsp; radu,&nbsp; podržava&nbsp; trenutno&nbsp; prihvaćeno&nbsp; grupisanje&nbsp; Evropskih vrsta&nbsp; roda&nbsp; <em>Marasmius</em>&nbsp; u&nbsp; sekcije&nbsp; na&nbsp; osnovu&nbsp; makro-&nbsp; i mikromorfolo&scaron;kih&nbsp; karaktera.&nbsp; Međutim,&nbsp; dobijeni&nbsp; rezultati&nbsp; ne podržavaju&nbsp; u&nbsp; potpunosti&nbsp; grupisanje&nbsp; nižih&nbsp; infrageneričkih kategorija (podsekcija i serija). Takođe, podsekcijska klasifikacija evropskih&nbsp; Marasmius&nbsp; vrsta&nbsp; analiziranih&nbsp; u&nbsp; ovom&nbsp; radu&nbsp; ne predstavlja monofiletske linije.</p> / <p>The&nbsp; goals&nbsp; of&nbsp; this&nbsp; doctoral&nbsp; thesis&nbsp; were&nbsp; to&nbsp; determine&nbsp; the macroscopic and microscopic characteristics of the fruit bodies of the&nbsp; genus&nbsp; Marasmius,&nbsp; Gymnopus&nbsp; and&nbsp; Mycetinis&nbsp; and&nbsp; their variability&nbsp; among&nbsp; populations,&nbsp; determining&nbsp; the&nbsp; influence&nbsp; of climatic factors on the morphological variability&nbsp; of&nbsp; fruit bodies,determining&nbsp; the&nbsp; number&nbsp; and&nbsp; distribution&nbsp; of&nbsp; individuals&nbsp; at selected&nbsp; sites&nbsp; within&nbsp; the&nbsp; National&nbsp; Parks&nbsp; of&nbsp; Serbia&nbsp; and Montenegro&nbsp; (Kopaonik,&nbsp; Stara&nbsp; Planina,&nbsp; Biogradska&nbsp; Gora)&nbsp; using the ISSR method, as well as determining basic population -genetic parameters&nbsp; and&nbsp; analysis&nbsp; of&nbsp; phylogenetic&nbsp; relations&nbsp; within&nbsp; the genus Marasmius.For&nbsp; the&nbsp; species&nbsp; M.&nbsp; alliaceus,&nbsp; it&nbsp; has&nbsp; been&nbsp; determined&nbsp; that&nbsp; the population&nbsp; of&nbsp; Stara&nbsp; planina&nbsp; is&nbsp; partially&nbsp; isolated,&nbsp; while&nbsp; the population&nbsp; of&nbsp; Biogradska&nbsp; gora&nbsp; has&nbsp; the&nbsp; highest&nbsp; heterogeneity&nbsp; in the&nbsp; investigated&nbsp; morphological&nbsp; characters.&nbsp; For&nbsp; the&nbsp; species&nbsp; G.androsaceus&nbsp; it was noticed that there was no clear&nbsp; segregation&nbsp; of populations,&nbsp;&nbsp; thus&nbsp;&nbsp; the&nbsp; investigated&nbsp; populations&nbsp; showed heterogeneity in the examined morphological characters. A&nbsp; statistically&nbsp; significant&nbsp; (p&lt;0.05)&nbsp; correlation&nbsp; between morphological&nbsp; and&nbsp; environmental&nbsp; factors&nbsp; in&nbsp; both&nbsp; analyzed species M. alliaceus and G. androsaceus was observed. Determination&nbsp; of&nbsp; the&nbsp; number&nbsp; and&nbsp; size&nbsp; of&nbsp; the&nbsp;&nbsp; genets&nbsp; by&nbsp; ISSR method in populations of species&nbsp; M. alliaceus,&nbsp; M. rotula and&nbsp; G.androsaceus,&nbsp; showed&nbsp; that&nbsp; these&nbsp; species&nbsp; form&nbsp; relatively&nbsp; small genes&nbsp; (from&nbsp; few&nbsp; centimeters&nbsp; to&nbsp; 15&nbsp; meters)&nbsp; located&nbsp; in&nbsp; relative proximity to each other (several meters ). By determining molecular diversity parameters (AMOVA, Fst) in populations&nbsp; of&nbsp; species&nbsp; M.&nbsp; alliaceus&nbsp; and&nbsp; G.&nbsp; androsaceus&nbsp; it&nbsp; has been found that the populations of both investigated species are significantly&nbsp; genetically&nbsp; differentiated&nbsp; (Fst&nbsp; values&nbsp; greater&nbsp; than 0.25), ie there is a small flow of gene between them. The phylogenetic analysis of ITS + LSU and ITS + LSU + EF-1ɑ sequence&nbsp; datasets&nbsp; supports&nbsp; the&nbsp; currently&nbsp; accepted, morphologicaly based&nbsp; groupings of sections of European species of genus&nbsp; Marasmius.&nbsp; However, the results obtained&nbsp; in this study do&nbsp; not&nbsp; fully&nbsp; support&nbsp; the&nbsp; grouping&nbsp; of&nbsp; lower&nbsp; infra-generic categories&nbsp; (subsections&nbsp; and&nbsp; series).&nbsp; Also,&nbsp; the&nbsp; subsection classification of the European Marasmius species analyzed in this paper does not represent monophyletic lineages.</p>
66

Entita / Entity

Jindra, Jakub Unknown Date (has links)
Informace může vytvářet určité entropické krajiny. Entropická krajina je složená ze zdrojů informace. Zdroj může být informačně přínosný nebo úplně zbytečný. Dobrý zdroj vytváří nízkou entropii, vysoký náboj, a špatný zdroj entropii vysokou s nízkým informačním nábojem. Touto optikou pak můžeme vidět fiktivní krajinu, která se kolem nás nalézá. Entita je její vizualizací, vytváří útesy, tam kde byly roviny, hory zkoncentrované informace a měsíční údolí s nulovou hodnotou.
67

Výpočetní metody pro anotační analýzy genetických variací / Computational Methods for Annotation Analysis of Genetic Variations

Fülöp, Tibor January 2015 (has links)
Analýza a interpretace variací DNA je důležité pro zkoumání genetického pozadí dědičnosti, nemocí a jiných fenotypových rysů. Tato práce stručně úvadí oblasti molekulární biologie a základních principů genetiky, popisuje metody pro anotační analýzy genetických variací, genomové asociační studie a metody pro analýzy obohacení s jejich implementací. V rámci této práce jsme představili nový webový nástroj Varanto, který může být použit k anotaci, vizualizaci a analýze genetických variací. Může být použit k analýze obohacení anotací pomocí hypergeometrického testu pro danou množinu variací. Varanto obsahuje uživatelské webové rozhraní vyvinuté pomocí frameworku Shiny jazyka R. Výkon a funkcionalita nástroje jsou testovány a demonstrovány podle výkonových benchmarků a na základě analýzy a interpretace dat z dříve publikovaných genomových asociačních studií.
68

Genetické předpoklady rychlostní schopnosti u hráčů 1. a 2. nejvyšší české fotbalové ligy / The Genetic predisposition of a speed ability among the players of the 1st and 2nd Czech football league

Thiel, Dan January 2021 (has links)
Title The genetic predisposition of a speed ability among the players of the 1st and 2nd Czech football league. Study aim To determine the impact of ACE I/D, ACTN3 R577X, AMPD1 Gln12X, BDKRB2 9/+9, IL1RN VNTR, NOS3 Glu298Asp, UCP2 Ala55Val polymorphisms genotype frequencies on the results of the speed ability motor tests. Methods DNA samples obtained from epithelial mouth were quantified and analyzed using the PCR method from 106 football players of the 1st and 2nd Czech football league (age 25,3 ± 4,69; weight 77,5 ± 7,33; height 181,2 ± 6,23). Genotype frequencies were estimated for the ACE I/D, ACTN3 R577X, AMPD1 Gln12X, BDKRB2 9/+9, IL1RN VNTR, NOS3 Glu298Asp, UCP2 Ala55Val polymorphism. Motor speed ability was tested by the vertical jump height, produced power and power impulse for the countermovement jump, countermovement jump without arms swing and squat jump. Isokinetic maximal power of flexors and extensors of the knee were tested at the angle speed 60ř.s-1 , 180ř.s-1 , 300ř.s-1 . Χ2 test (Pearson's chi-square test) was used to determine the genotypes difference for the parameters of the motor speed ability tests in the football players who exceeded 80th percentil compare to the other football players. Kruskal- Wallis test was used to determine dependence (p = 0,05) of the genotypes...
69

Porovnání genetické variability geograficky vzdálených populací vybraných evropských mořských druhů hlaváčů / Comparison of the genetic variability of geographically distant populations of selected species of European marine gobies

Chalupecká, Katarína January 2018 (has links)
Gobies (Gobiidae, Actinopterygii) are small, predominantly cryptic, marine, brackish and freshwater fishes. They abundantly inhabit coastal waters, although their occurrence is far from being mapped due to their inconspicity, often hidden lifestyle and a lack of commercial use. Information about distribution of many species is therefore still rather poor. Many species are known only from a few locations scattered throughout the Mediterranean Sea and the Atlantic. This suggests that most species could actually have a relatively continuous distribution area. Comparing the genetic variability of geographically distant populations of the same species can help to detect whether there is some population subdivision and whether populations are genetically isolated from each other. The aim of my thesis was to compare genetic variability of the populations of eight goby species: Corcyrogobius liechtensteini, Gobius cruentatus, Gobius geniporus, Gobius incognitus, Chromogobius quadrivittatus, Chromogobius zebratus, Millerigobius macrocephalus and Zebrus zebrus within Mediterranean Sea and north-eastern Atlantic Ocean. Samples used in this work were collected from two Atlantic (Spain and Portugal) and seven Mediterranean localities (France, Sicily, Croatia, Montenegro, Greece, and Cyprus - northern and...
70

Výuka Mendelovské dědičnosti pomocí didaktické hry / Teaching Mendelian inheritance by didactic game

Lišková, Kateřina January 2020 (has links)
This diploma thesis focuses on the education of genetics to grammar schools and students' comprehension of genetics. This abstract scientific discipline is considered difficult to learn so I decided to prepare educational materials with the aim to improve students' understanding of the topic. The main aim of the thesis was to prepare and test a didactic game focused on Mendelian inheritance and compare the effectivity of this kind of interactive education compared with the classical explanatory style of education. Other aims included evaluating the influence of other variables; comparing the difficulty of individual terms in genetics and the connection within chosen triplet of terms; and identifying the most common misconceptions. The data was collected in four classes of upper graders at two grammar schools by newly prepared questionnaire focused on demographic and knowledge. The results showed that the didactic game was as efficient as the classical explanatory method at creating short term knowledge Students had a bigger problem with explaining the connection among the terms than defining the individual terms. The most complicated term reported by the students was chromosome. It was the only term in which there wasn't any improvement between pre-test and post-test. Part of this thesis is also...

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