Multistability is a fundamental attribute of the dynamics of neuronal systems under normal and pathological conditions. The mechanism of bistability of bursting and silence is not well understood and to our knowledge has not been experimentally recorded in single neurons. We considered four models. Two of them described the dynamics of a leech heart interneuron: the canonical model and a low-dimensional model. The other two models described mammalian pacemakers from the respiratory center. We investigated the low-dimensional model and identified six different types of multistability of dynamical regimes. We described six generic mechanisms underlying the co-existence of oscillatory and silent regimes. The mechanisms are based either on a saddle equilibrium or a saddle periodic orbit. The stable manifold of the saddle equilibrium or the saddle orbit sets the threshold between the regimes. In the two models of the leech interneuron the range of the controlling parameters supporting the co-existence of bursting and silence is limited by the Andronov-Hopf and homoclinic bifurcations (Malashchenko, Master Thesis 2007). The bistability was found in a narrow range of the leak currents' parameters. Here, we introduced a propensity index to bistability as the width of the range on a bifurcation diagram; we investigated how the propensity index was affected by modifications of the ionic currents, and found that conductances of only two currents substantially affected the index. The increase of the conductance of the hyperpolarization-activated current, Ih, and the reduction of the fast Ca2+ current, ICaF, notably increased the propensity index. These findings define modulatory conditions under which we suggest the bistability of bursting and silence could be experimentally revealed in leech heart interneurons. We hypothesize that this mechanism could be commonly found in a large variety of neuronal models. We applied our techniques to models of vertebrate neurons controlling respiratory rhythm, which represent two types of inspiratory pacemakers of the Pre-Bӧtzinger Complex. We showed that both types of neurons could exhibit bistability of bursting and silence in accordance with the mechanism which we described.

Ths thesis demonstrates how theory and praxis may be integrated within a postcolonial, or more specifically, anticolonial frame. It argues for the necessity of telling, listening and responding to personal narratives as a catalyst for understanding the construction of identities and their relationship to place. Tlus is acheved through a theorisation of narrative and a critique of postcolonialism. Three 'sites' of contestation are visited to provide this critique: the "Patterns of Life: The Story of the Aboriginal People of Western Australia" exhibition at the Perth Museum; a comparison of Western Australian legislation that governed the lives of Aboriginal people from 1848 to the present and, the life story of Alice Nannup; and, an analysis of the Australian Institute Judicial Association's "Aboriginal Culture: Law and Change" seminar for magistrates. Most importantly, this work foregrounds strategies for negotiating a just basis for coexistence between indigenous and non-indigenous Australians.

RF front-ends are nonlinear systems that have nonlinear frequency response and, hence, can impair receiver performance by harmful adjacent channel interference in non-intuitive ways. Next generation wireless networks will see unprecedented diversity across receiver and radio technologies accessing the same band of spectrum in spatio-temporal proximity. Ensuring adjacent channel co-existence is of prime importance for successful deployment and operations of next generation wireless networks. Vulnerabilities of receiver front-end can have a severe detrimental effect on network performance and spectrum co-existence. This dissertation addresses the technological challenges in understanding and accounting for receiver sensitivities in the design of next generation wireless networks. The dissertation has four major contributions. In the first contribution, we seek to understand how receiver nonlinearity impacts performance. We propose a computationally efficient framework to evaluate the adjacent channel interference in a given radio/spectrum environment. We develop novel tractable representation of receiver front-end nonlinearity to specify the adjacent channel signals that contribute to the interference at the desired channel and the total adjacent channel interference power at a given desired channel. In the second contribution, we seek to understand how the impact of receiver nonlinearity performance can be quantified. We quantify receiver performance in the presence of adjacent channel interference using information theoretic metrics. We evaluate the limits on achievable rate accounting for RF front-end nonlinearity and provide a framework to compare disparate receivers by forming generalized metrics. In the third contribution, we seek to understand how the impact of receiver nonlinearity can be managed at the network level. We develop novel and comprehensive wireless network management frameworks that account for the RF nonlinearity, impairments, and diversity of heterogeneous wireless devices. We further develop computationally efficient algorithms to optimize the proposed framework and examine network level performance. We demonstrate through extensive network simulations that the proposed receiver-centric frameworks provide substantially high spectrum efficiency gains over receiver-agnostic spectrum access in dense and diverse next generation wireless networks. In the fourth contribution, we seek to understand how scalable interference networks are with receiver nonlinearity. We propose practical achievable schemes for interference avoidance and assess the scalability of the next generation wireless networks with interference due to receiver nonlinearity. Further, we develop an algorithmic scheme to evaluate the upper bound on scalability of nonlinear interference networks. This provides valuable insights on scalability and schemes for nonlinear adjacent channel interference avoidance in next generation shared spectrum networks. / Ph. D.

Regulation of genetically modified organisms and nanotechnology (comparison of British, Czech and Slovak legislation in the context of EU) The aim of this thesis is to first compare the british, czech and slovak legislation relating to genetically modified organisms. By the analysis of their respective features, the author points out the difficult bits and tries to look for the ideal solutions to the current problems of the european GM legislation. In spite of the fact, that the european legislation in this field is highly harmonised, there are still some areas that can be regulated by the member states as well as some holes waiting to be fixed. This thesis is composed of six main chapters which correspond to six main topics of present biotechnology legislation that are in the author's opinion the most significant. First chapter deals with the basic issues of releases of genetically modified organisms into the environment, on market, and with their contained use. Secondly, the author dissects the GM labelling and traceability legislation and shows the various thresholds of GM presence that are applicable to different areas. Third chapter then analyses the rules on co-existence between GM plants on one hand and conventional and organic plants on the other. Nextly, the unilateral acts of member...

A trade-off between seed size and seed number is central in seed ecology, and has been suggested to be related to a trade-off between competition and colonization, as well as to a trade-off between stress tolerance and fecundity. Large seeds endure hazards during establishment, such as shading, drought, litter coverage and competition from other plants, better than do small seeds, due to a larger amount of stored resources in the seed. Small seeds, however, are numerous and small-seeded species are therefore more fecund. Moreover, a pattern with small-seeded species being associated with open habitats and large-seeded species being associated with closed habitats has been reported in the literature. In this thesis I assess effects of seed size on recruitment, and how relationships between seed size and recruitment may relate to habitat conditions. Seed sowing experiments were performed in the field to assess inter- and intra-specific relationships between seed size and recruitment in open and closed habitats (Paper I and II). Seed removal experiments were performed in the field to assess what effects seed predation may have on a relationship between seed size and recruitment (Paper III). A garden experiment was performed based on contests between larger-seeded and smaller-seeded species, in order to examine different models on co-existence of multiple seed size strategies. The results showed that there was a weak positive relationship between seed size and recruitment in the field, and that this relationship was only weakly and inconclusively related to habitat (Paper I and II). Seed removal was negatively related to seed size in closed habitats and unrelated to seed size in open habitats (Paper III). This indicates that any positive relationship between seed size and recruitment may be an effect of higher seed removal in small-seeded species. However, when grown under controlled conditions in a garden experiment, there was a clear advantage of larger-seeded species over smaller-seeded species (Paper IV). This advantage was unaffected by seed density, indicating that there was no competitive advantage of the larger-seeded species. Instead, indirect evidence suggests that larger-seeded species exhibit higher tolerance to stress. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Accepted.</p><p> </p>

Speciation can be viewed as the formation of reproductive barriers between different populations. This thesis investigates patterns of natural and sexual selection shaping reproductive barriers between two hybridizing flycatchers (i.e. collared – and pied flycatchers). Behaviorally driven sexual isolation depends on both the availability of conspecific mates and on discrimination ability of individuals. My results demonstrate that these two factors may also interact. Discrimination abilities may change in response to the relative frequency of two interbreeding species. The underlying reason appears to be that male pied flycatchers have a song that incorporates more elements of the song characteristics of male collared flycatchers into their own song repertoires when occurring in areas inhabited predominantly by collared flycatchers. I investigated selection pressures acting on hybrids. In migratory species, hybrid fitness might be reduced as a consequence of intermediate suboptimal migration routes (extrinsic post zygotic isolation). Comparison of stable isotope signatures of revealed that parental species have separate wintering grounds, but hybrids appear to winter at the same location as pied flycatchers. A possible dominance effect in the inheritance of migration direction may hence reduce this potential cost. This interpretation is supported by the absence of a reduction in juvenile to adult survival of hybrids. By further comparing male hybrid fitness to that of the parental species, using lifehistory data, I demonstrate that hybrid males experience a moderate reduction in fitness (mainly through a sexually selected disadvantage). Sexual selection acting on male hybrids can play a major role in the speciation process because when the same characters affect assortative mating as well as hybrid fitness, reinforcement of reproductive barriers becomes more likely. Even when reproductive isolation is completed- the fate of newly formed species may be uncertain since they may strongly compete for ecological space. Long-term persistence of ecologically similar, species requires that there are spatial or temporal variation in their relative fitness. The growth of nestling pied flycatchers is less affected by harsh environmental conditions. We suggest that a regional co-existence of the two flycatcher species is due to a lifehistory trade-off between interference competitive ability and robustness to a harsh conditions. Overall, the studies in this thesis reveal the complexity of the interactions between mate choice and competition in shaping sexual signals. Furthermore, it suggests that natural selection is moderate on hybrid males and that sexual selection may have strong implications for the maintenance of species integrity.

The co-existence of bursting activity and silence is a common property of various neuronal models. We describe a novel mechanism explaining the co-existence of and the transition between these two regimes. It is based on the specific homoclinic and Andronov-Hopf bifurcations of the hyper- and depolarized steady states that determine the co-existence domain in the parameter space of the leech heart interneuron models: canonical and simplified. We found that a sub-critical Andronov-Hopf bifurcation of the hyperpolarized steady state gives rise to small amplitude sub-threshold oscillations terminating through the secondary homoclinic bifurcation. Near the corresponding boundary the system can exhibit long transition from bursting oscillations into silence, as well as the bi-stability where the observed regime is determined by the initial state of the neuron. The mechanism found is shown to be generic for the simplified 4D and the original 14D leech heart interneuron models.

The topic of family is in present-day postmodern time one of the most biting. We occur in one of the next marginal terms where traditional family slowly disappears and a modern family has so many variabilities, directions and instability we don't even know what structure it takes in next decades. Goal of my work is to find out and describe how college students across the Czech Republic feel about marriage and family. My objective is to find out, whether college students did have in their worth list family and whether it was highly rated on it. For achieving objective, I set down two hypothesis. Hypothesis no. 1: Family is in the TOP 3 in worth lists of college students. Hypothesis no. 2: Cohabitation is more preferred then marriage by college students. I found out in research that family actually is in the TOP 3 in worth lists of college students. There was affirmation of opinion on cohabitation too. College students prefer cohabitation before marriage. Interesting fact is that students prefer cohabitation only until their child is born. In the theoretical part I focused on what family is and what is its function, on historical development of both marriage and cohabitation. Next, I described changes which came into being in partnerships which lead to marriage or choosing a cohabitation. Practical part of the work is filled with quantitative research by interview surveys. I researched into the sort of college students across the Czech Republic, who were chosen by random sample in a specific way, in which it fulfils representativeness criteria. Overall, 916 respondents took part in my research. Results are shown in numbers and percentage and graphs and tables were used to process data.

Local participation in nature conservation has gained more attention over the last decades due to international conventions as well as local and national initiatives. This development can be seen as a reaction to a more expert oriented nature conservation characterized by centralized control and strict preservation of so called "original" nature. The overall objective of this thesis is to contribute to research on new forms of conservation where democracy and local participation is included. The case study focuses on the process of producing a pre-study for a suggested national park in southern Jämtland in the Swedish mountain region, and aims to investigate to what extent local participation was included. The pre-study was led by the Swedish Environmental Protection Agency (SEPA) and the County Administrative Board (CAB) in Jämtland. The thesis is to some extent grounded in a political ecological perspective, which highlights connections between politics, societies and the environment. The methods used are semi-structured in-depth interviews and literature studies. The results show that although the stakeholders interviewed to some extent share views on the process, there are also differences. The SEPA and the CAB are generally satisfied with the result while there is some dissatisfaction among others. However, all stress that respect and dialogue are important and most actors see zoning and channeling within a potential park as part of a solution to past conflicts in the area. How the management structure will take form and to which extent it will include local participation has not been discussed in detail so far, although the Sámi demand to be included in any future management. These questions will be further investigated by the SPEA if they decide to proceed in a national park process. / Bortom konflikter: utmaningar och möjligheter i svenska fjäll

Abstract In this work, phase structure and the surface morphology effects on the optical properties of nonlinear active nanocrystalline PZT thin films, with the high refractive index (n&#160;≈&#160;2.5), were studied. A preliminary thickness-temperature map of the majority phase was presented, showing the dependence of room temperature deposited films thickness and post-annealing temperature on the crystallization and surface morphology. Changes in structural phase and surface morphology were found to define the optical properties of the films. The optical absorption edge shifted to shorter wavelengths with decreasing film thickness and post-annealing temperature, which led to an increase in band gap energies with ΔEg&#160;≈&#160;0.55eV. Structural phase evolution induced surface effects caused the definite diffuse elements in the transmission spectra of the films. Low and evenly distributed scattering amplitudes in k-space were seen for single-phase oriented films with non-textured surfaces and led to low diffuse transmission values with TD&#160;≈&#160;5%. Confined and increased scattering amplitudes in k-space were seen for films with phase co-existence, leading to microstructure-induced textured surfaces and increased diffuse transmission values with TD&#160;≈&#160;50%. Diffuse transmission properties of the films were also calculated from surface profile data, using scalar scattering theory. The results showed very good agreement with the experimentally defined values. The difference between modelled and measured values was 3.8% at the maximum. Also changes in the surface morphology and crystal orientation were found to modulate the full width at half maximum Δβ values of the TE0 optical mode, indicating a strong dependence on the surface scattering process. Sharp optical mode widths Δβ&#160;≈&#160;0.0048 and Δβ&#160;≈&#160;0.0006, for single-phase oriented and amorphous-like films, respectively, were found. / Tiivistelmä Tässä työssä tutkittiin nanokiteisten korkean taitekertoimen (n&#160;≈&#160;2.5) omaavien PZT ohutkalvojen optisten ominaisuuksien riippuvuutta ohutkalvon faasirakenteesta ja pinnan morfologiasta. Rakenneanalyysien perusteella muodostettiin paksuus-lämpötila faasikartta havainnollistamaan jälkihehkutuslämpötilan ja kalvon paksuuden vaikutuksia huoneenlämpötilassa pulssilaserkasvatusmenetelmällä kasvatettujen ohutkalvojen faasirakenteen ja pinnan morfologian muokkautumiseen. Muutokset kalvon faasirakenteessa ja pinnan morfologiassa määrittivät täysin kalvon optiset ominaisuudet siten, että optinen absorptioreuna siirtyi alemmille aallonpituuksille kalvon paksuuden ja jälkihehkutuslämpötilan pienentyessä, aiheuttaen energiaraon kasvun (ΔEg&#160;≈&#160;0.55 eV). Faasirakenteen indusoiman pinnan morfologian muokkautuminen määritteli myös ohutkalvon sirontaspektrin yksityiskohdat aaltolukuavaruudessa. Tasaisesti jakautunut pienen amplitudin omaava sirontaspektri ja alhainen diffuusi sironta (TD&#160;≈&#160;5&#160;%) oli ominaista yksifaasisille, voimakkaasti orientoituneille ohutkalvoille, kun taas alhaisille aaltolukuarvoille rajoittunut korkean amplitudin omaava sirontaspektri ja lisääntynyt diffuusi sironta (TD&#160;≈&#160;50&#160;%) oli ominaista kaksifaasisille ohutkalvoille. Tutkittujen ohutkalvojen sirontaspektrin diffuusi komponentti laskettiin myös käyttäen skalaaria sirontateoriaa. Ero laskettujen ja mitattujen arvojen välillä oli maksimissaan 3.8&#160;%. Muutokset ohutkalvojen pinnan morfologiassa ja faasirakenteessa havaittiin myös moduloivan optisen TE0 moodin puoliarvoleveyttä. Alhaisimmat pouoliarvoleveydet havaittiin yksifaasisilla (Δβ&#160;≈&#160;0.0048) ja amorfisenkaltaisilla ohutkalvoilla (Δβ&#160;≈&#160;0.0006).