A novel cost effective and high-throughput isolation and identification method for marine microalgae

Background: Marine microalgae are of major ecologic and emerging economic importance. Biotechnological screening schemes of microalgae for specific traits and laboratory experiments to advance our knowledge on algal biology and evolution strongly benefit from culture collections reflecting a maximum of the natural inter- and intraspecific diversity. However, standard procedures for strain isolation and identification, namely DNA extraction, purification, amplification, sequencing and taxonomic identification still include considerable constraints increasing the time required to establish new cultures. Results: In this study, we report a cost effective and high-throughput isolation and identification method for marine microalgae. The throughput was increased by applying strain isolation on plates and taxonomic identification by direct PCR (dPCR) of phylogenetic marker genes in combination with a novel sequencing electropherogram based screening method to assess the taxonomic diversity and identity of the isolated cultures. For validation of the effectiveness of this approach, we isolated and identified a range of unialgal cultures from natural phytoplankton communities sampled in the Arctic Ocean. These cultures include the isolate of a novel marine Chlorophyceae strain among several different diatoms. Conclusions: We provide an efficient and effective approach leading from natural phytoplankton communities to isolated and taxonomically identified algal strains in only a few weeks. Validated with sensitive Arctic phytoplankton, this approach overcomes the constraints of standard molecular characterisation and establishment of unialgal cultures

Physiology, syntrophy and viral interplay in the marine sponge holobiont

Holobionts result from intimate associations of eukaryotic hosts and microbes and are now widely accepted as ubiquitous and important elements of nature. Marine sponge holobionts combine simple morphology and complex microbiology whilst diverging early in the animal kingdom. As filter feeders, sponges feed on planktonic bacteria, but also harbour stable species-specific microbial consortia. This interaction with bacteria renders sponges to exciting systems to study basal determinants of animal-microbe symbioses. While inventories of symbiont taxa and gene functions continue to grow, we still know little about the symbiont physiology, cellular interactions and metabolic currencies within sponges. This limits our mechanistic understanding of holobiont stability and function. Therefore, this PhD thesis set out to study the questions of what individual symbionts actually do and how they interact. The first part of this thesis focuses on the cell physiology of cosmopolitan sponge symbionts. For the first time, I characterised the ultrastructure of dominant sponge symbiont clades within sponge tissue by establishing fluorescence in situ hybridization-correlative light and electron microscopy (FISH-CLEM). In combination with genome-centred metatranscriptomics, this approach revealed structural adaptations of symbionts to process complex holobiont-derived nutrients (i.e., bacterial microcompartments and bipolar storage polymers). Next, we unravelled complementary symbiont physiologies and cell co-localisation indicating vivid symbiont-symbiont metabolic interactions within the holobiont. This suggests strategies of nutritional resource partitioning and syntrophy to dominate over spatial segregation to avoid competitive exclusion- a mechanistic framework to sustain high microbial diversity. By combining stable isotope pulse-chase experiments with metabolic imaging, we demonstrated that symbionts can account for up to 60 % of the heterotrophic carbon and nitrogen assimilation in sponges. Thus, sponge symbiont action determines sponge-driven biochemical cycles in marine ecosystems. Finally, I explored the role of phages in the sponge holobiont focussing on tripartie phage-microbe-host interplay. Sponges appeared as rich reservoirs of novel viral diversity with 491 previously unidentified genus-level viral clades. Further, sponges harboured highly individual, yet species-specific viral communities. Importantly, I discovered that phages, termed “Ankyphages”, abundantly encode ankyrin proteins. Such “Ankyphages” I found to be widespread in host-associated environments, including humans. Using macrophage infection assays I showed that phage ankyrins aid bacteria in eukaryote immune evasion by downregulating eukaryotic antibacterial immunity. Thus, I identified a potentially widespread mechanism of tripartite phage-prokaryote-host interplay where phages foster animal-microbe symbioses. Altogether, I draw three main conclusions: The sponge holobiont is a metabolically intertwined ecosystem, with symbiont action impacting the environment, and tripartite phage-prokaryote-eukaryote interplay fostering symbiosis

Phases of spin- and mass-imbalanced ultracold Fermi gases in harmonic traps

We analyze the phase structure of mass- and spin-imbalanced unitary Fermi gases in harmonic traps. To this end, we employ Density Functional Theory in the local density approximation. Depending on the values of the control parameters measuring mass and spin imbalance, we observe that three regions exist in the trap, namely: a superfluid region at the center, surrounded by a mixed region of resonantly interacting spin-up and spin-down fermions, and finally a fully polarized phase surrounding the previous two regions. We also find regimes in the phase diagram where the existence of a superfluid region at the center of the trap is not energetically favored. We point out the limitations of our approach at the present stage, and call for more detailed (ab initio) studies of the equation of state of uniform, mass-imbalanced unitary Fermi gases.Comment: 10 pages, 7 figure

A methodology of a sensitivity analysis in dem experiments

In this publication a sensitivity analysis for DEM modelparameters with respect to the pile- and the oedometer experiment is described. The analysis is performed with Sobol’ indices. Since the huge computational effort of the corresponding DEM models different metamodels are used to determine these indices. The (RSM) metamodels are established by using Latin Hypercube sampling points. A three-dimensional ansatz for the determination of the angle of repose as well as the algorithm of a force-controlled plate is described in order to get results for the pile- and the oedometer experiment

Hromadné žaloby v soukromoprávním vymáhání soutěžního práva

in English This master's thesis is concerned with collective redress mechanisms in the area of competition law of the European Union. Taking into account the ongoing modernization of private enforcement of competition law, the European Commission had decided to create a complementary system of collective and representative actions. Implementation of such instruments was recommended by the European Commission in Commission Recommendation of 11 June 2013 on common principles for injunctive and compensatory collective redress mechanisms in the Member States concerning violations of rights granted under Union Law. The main research question of this thesis is whether the European Commission has taken a wise approach towards collective redress mechanisms by creating the complementary system of collective redress, using the opt-in mechanism. This master's thesis is divided into 5 main chapters. In the first chapter, the readers are introduced to the topic of enforcement of competition law in the European Union. Further, the main research question is laid down, followed by the sources and methodology used in this thesis. The second chapter shortly describes each way of enforcement of competition law in the European Union. It aims mainly at describing private enforcement of competition law, as it forms the...in Czech Tato diplomová práce se zabývá problematikou kolektivní právní ochrany v soutěžním právu Evropské Unie. V rámci probíhající modernizace soukromoprávního vymáhání soutěžního práva se Evropská Komise rozhodla pro vytvoření komplementárního systému hromadných a reprezentativních žalob, jejichž zakotvení v právních řádech členských států Evropské Unie navrhla v Doporučení Komise ze dne 11. června 2013 o společných zásadách pro prostředky kolektivní právní ochrany týkající se zdržení se jednání a náhrady škody v členských státech v souvislosti s porušením práv přiznaných právem Unie. Hlavní výzkumnou otázkou této diplomové práce je, zda Evropská Komise učinila správně, když se rozhodla pro vytvoření komplementárního systému kolektivní právní ochrany využívajícího tzv. opt-in metody. Po obsahové stránce je tato diplomová práce rozdělena do 5 hlavních kapitol. V první kapitole je čtenář krátce uvozen do problematiky vymáhání soutěžního práva v Evropské Unii, a zároveň je vytyčena výzkumná otázka, zdroje a metodologie. Druhá kapitola stručně popisuje jednotlivé formy vymáhání soutěžního práva v Evropské Unii. Zaměřuje se zejména na soukromoprávní formu vymáhání soutěžního práva, která tvoří esenciální právní základ pro kolektivní právní ochranu. Pro tuto diplomovou práci je ovšem nejdůležitější...Department of European LawKatedra evropského právaFaculty of LawPrávnická fakult

Experimental modeling of thermal cycles

Import 05/08/2014Bakalářská práce je zaměřena na experimentální modelování teplotních cyklů. Práce je rozdělena na teoretickou a experimentální část. V teoretické části bakalářské práce je popsán rozbor diagramu ARA a jsou popsány vlastnosti oceli, která byla použita při modelování teplotních cyklů. V druhé části teorie je popsán rozbor teplotních cyklů, které probíhají při svařování, zejména teplotní pásma tepelně ovlivněné oblasti. V experimentální části je popsán pracovní postup teplotního cyklu na teplotním simulátoru a také výsledné grafy z experimentálního modelování teplotních cyklů. V závěru experimentální části je uvedena metalografická zkouška, zkouška tvrdosti a rozbor diagramu ARA pro konkrétní vzorek, který byl použit při modelování teplotních cyklů.The Bachelor thesis is focused on the experimental modeling of thermal cycles. The thesis is divided on theoretical and practical part. In the theoretical thesis is described ARA diagram and there is also described properties of steel, which was used for modeling thermal cycles. In second part of theory, there are described thermal cycles, which progress during welding, especially temperature zones of heat affected zone. In the experimental part is described workflow of temperature cycle on the temperature simulator and also there are final graphs of the experimental modeling of thermal cycles. In the end of the experimental part is showed metallographic exam, hardness test and analysis of ARA diagram for the sample, which was used for modeling of thermal cycles.632 - Katedra materiálů a technologií pro automobilyvelmi dobř