Ontogenetic niche shifts generally coincide with changes in size, morphology, behavior, and/or feeding preferences during development, resulting in a shift in preferred habitat. In aquatic species, these ontogenetic niche shifts are often associated with habitat-dependent changes in competition and/or predation dynamics, expressed as a size-depth relationship where the larger-bodied adults occupy deeper habitats while the smaller-bodied juveniles primarily reside in shallower regions. While the influence of interspecific interactions on size-structured habitat occupancy has been well studied, few have examined the potential role of intraspecific agonistic interactions between size classes in ontogenetic niche shifts. A simulation model was developed to test whether the size-specific habitat occupancy observed in signal crayfish can be explained by the size-structured individual responses to agonistic interaction, where the smaller-bodied juvenile responds to the interaction with an escape movement, to avoid engagement and the risk of mortality or injury from the adult. The simulated movements of signal crayfish resulted in higher juvenile occupancy of riffles relative to pools reflecting a greater rate of escape from adults into riffles, away from the higher densities of adults in their preferred habitat (i.e. pools). This provides evidence that the juvenile escape response to size-structured, intraspecific, agonistic interactions may contribute to ontogenetic niche shifts.

Bakalaurinį darbą sudaro: anotacija, įvadas, 4 skyriai, išvados, literatūros sąrašas ir priedai. Darbo apimtis – 42 puslapiai. Bakalaurinio darbo pirmajame skyriuje yra pateikta teorinė medžiaga apie Saulės sandarą bei jos energetinį potencialą. Antrajame skyriuje analizuota ir aprašyta FE sandara, charakteristikos, parametrai, FVM energijos konversijos efektyvumas. Aptarta užsienio autorių aprašyti eksperimentiniai tyrimai su FVM tiriant energetinio efektyvumo priklausomybę nuo modulių temperatūros. Trečias skyrius - praktinė dalis, kurioje aprašyti laboratorijoje atlikti eksperimentinių tyrimų su FVM rezultatai. Analizuota, kaip kinta FVM parametrai (trumpo jungimo srovė, atviros grandinės įtampa, galia). Ketvirtajame skyriuje aprašytos fotoelektros vystymosi tendencijos ir plėtros perspektyvos. / The bachelor thesis includes the summary, the introduction, four sections, the conclusion, the literature list and appendices. The thesis consists of 42 pages. The first section outlines the theoretical material about the structure of the sun and its energy potential. The second section analyses and describes the structure of PV, properties, parameters, and the efficiency of PVM energy conversion. The thesis includes the experimental analyses of foreign authors on the efficiency of PVMs depending on the temperature of the modules. The third section is the empirical part, which presents the results of the laboratory experiment with PVMs. The analysis includes the variability of parameters of PVMs (short circuit current, open circuit voltage, power). The fourth section describer the prospects of photovoltaic electricity and its development potential.

In financial risk management it is essential to be able to model dependence in markets and portfolios in an accurate and efficient way. A high positive dependence between assets in a portfolio can be devastating, especially in times of crises, since losses will most likely occur at the same time in all assets for such a portfolio. The dependence is therefore directly linked to the risk of the portfolio. The risk can be estimated by several different risk measures, for example Value-at-Risk and Expected shortfall. This paper studies some different ways to measure risk and model dependence, both in a theoretical and empirical way. The main focus is on copulas, which is a way to model and construct complex dependencies. Copulas are a useful tool since it allows the user to separately specify the marginal distributions and then link them together with the copula. However, copulas can be quite complex to understand and it is not trivial to know which copula to use. An implemented copula model might give the user a "black-box" feeling and a severe model risk if the user trusts the model too much and is unaware of what is going. Another model would be to use the linear correlation which is also a way to measure dependence. This is an easier model and as such it is believed to be easier for all users to understand. However, linear correlation is only easy to understand in the case of elliptical distributions, and when we move away from this assumption (which is usually the case in financial data), some clear drawbacks and pitfalls become present. A third model, called historical simulation, uses the historical returns of the portfolio and estimate the risk on this data without making any parametric assumptions about the dependence. The dependence is assumed to be incorporated in the historical evolvement of the portfolio. This model is very easy and very popular, but it is more limited than the previous two models to the assumption that history will repeat itself and needs much more historical observations to yield good results. Here we face the risk that the market dynamics has changed when looking too far back in history. In this paper some different copula models are implemented and compared to the historical simulation approach by estimating risk with Value-at-Risk and Expected shortfall. The parameters of the copulas are also investigated under calm and stressed market periods. This information about the parameters is useful when performing stress tests. The empirical study indicates that it is difficult to distinguish the parameters between the stressed and calm market period. The overall conclusion is; which model to use depends on our beliefs about the future distribution. If we believe that the distribution is elliptical then a correlation model is good, if it is believed to have a complex dependence then the user should turn to a copula model, and if we can assume that history will repeat itself then historical simulation is advantageous.

Adult addicts learning motivation Master’s degree diploma thesis. The aim of this thesis is to reveal the structure and expression of addicts learning motivation who are being treated in rehabilitative communities, to evaluate learning as a subject of the social integration. 21 addict was involved into the research. All these men are being treated in addict rehabilitation communities “Hope lighthouse” and “Life’s issue”. 29 categories of addicts learning motivation have been determined using the data of the interview. The largest and the most influenced on the learning motivation catgories are ,,expression of participation”, ,,environment maintaining the rehabilitation”, Self-expression and self-realisation”, ,,internal resourses”, ,,actuality of the learning motivation”, a need of information for educational resources. The basic speculation arranged by the author is confirmed that mutual help model of the community encourages addicts to strengthen learningmotivation, to integrale into the learning society.

With the advent of Chip Multi Processors (CMPs), improving performance relies on the programmers/compilers to expose thread level parallelism to the underlying hardware. Unfortunately, this is a difficult and error-prone process for the programmers, while state of the art compiler techniques are unable to provide significant benefits for many classes of applications. An interesting alternative is offered by systems that support Thread Level Speculation (TLS), which relieve the programmer and compiler from checking for thread dependencies and instead use the hardware to enforce them. Unfortunately, data misspeculation results in a high cost since all the intermediate results have to be discarded and threads have to roll back to the beginning of the speculative task. For this reason intermediate checkpointing of the state of the TLS threads has been proposed. When the violation does occur, we now have to roll back to a checkpoint before the violating instruction and not to the start of the task. However, previous work omits study of the microarchitectural details and implementation issues that are essential for effective checkpointing. Further, checkpoints have only been proposed and evaluated for a narrow class of benchmarks. This thesis studies checkpoints on a state of the art TLS system running a variety of benchmarks. The mechanisms required for checkpointing and the costs associated are described. Hardware modifications required for making checkpointed execution efficient in time and power are proposed and evaluated. Further, the need for accurately identifying suitable points for placing checkpoints is established. Various techniques for identifying these points are analysed in terms of both effectiveness and viability. This includes an extensive evaluation of data dependence prediction techniques. The results show that checkpointing thread level speculative execution results in consistent power savings, and for many benchmarks leads to speedups as well.

Kulturorganisationer är en typ av organisationer som skiljer sig från andra. Istället för att drivas av ett vinstintresse styrs de av konstnärliga värderingar. En viktig förutsättning för att deras verksamhet ska fungera är statliga subventioneringar, vilket medför att de blir starkt knutna till statens nycker. År 2008 infördes satsningen Skapande skola, vilken innebär att skolhuvudmän kan söka bidrag för att genomföra kulturprojekt för grundskoleelever i sam-arbete med professionella kulturaktörer. Denna satsning är en betydande potentiell resurs i kulturaktörernas omgivning och vi intresserar oss för hur de påverkas av att nya resurser till-gängliggörs. Studien består av kvalitativa intervjuer med personer från sex olika kulturorganisationer från skilda delar av Sverige. Dessa kombineras med sekundärdata i form av en sammanställning av återrapporteringar av Skapande skola-projekt från år 2011, vilket är det senast tillgängliga materialet. Empirin analyserades utifrån teorier om resource dependence och institutionell isomorfism. Studien visar att samtliga organisationer har kompletterat sin verksamhet i linje med kraven från Skapande skola. De olika värderingarna inom skolvärlden och kulturvärlden ger även upphov till en kulturkrock som påverkar tillämpningen av resursen.

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The primary aim of this thesis is the elucidation of covariate effects on the dependence structure of random variables in bivariate or multivariate models. We develop a unified approach via a conditional copula model in which the copula is parametric and its parameter varies as the covariate. We propose a nonparametric procedure based on local likelihood to estimate the functional relationship between the copula parameter and the covariate, derive the asymptotic properties of the proposed estimator and outline the construction of pointwise confidence intervals. We also contribute a novel conditional copula selection method based on cross-validated prediction errors and a generalized likelihood ratio-type test to determine if the copula parameter varies significantly. We derive the asymptotic null distribution of the formal test. Using subsets of the Matched Multiple Birth and Framingham Heart Study datasets, we demonstrate the performance of these procedures via analyses of gestational age-specific twin birth weights and the impact of change in body mass index on the dependence between two consequent pulse pressures taken from the same subject.

Asymmetric dependence (AD) is defined as dependence that differs across opposing regions of the joint return distribution. Recent evidence of AD between equity returns suggests that dependence can be decomposed into a linear component, captured by the correlation matrix, and a higher order component. When these higher order terms are characterised by increased correlation in bear or bull markets, the effectiveness of diversification strategies is reduced. To the extent that an investor is unable to completely diversify these higher order terms of dependence, it follows that they should be reflected in asset prices and managed explicitly during the portfolio construction process. The aim of this thesis is to determine the extent of AD amongst asset returns, to investigate whether AD is priced and to develop a means of managing AD in the portfolio. I justify the existence of AD and the separation of AD from linear dependence via the bivariate Edgeworth expansion, finding that the joint return distribution may be described by an infinite number of higher order co-moments. Correlation (and hence β) describes one dimension of an infinite number of higher dimensions describing dependence. To determine the importance of AD in finance, I first develop measures that can detect AD independent of the level of linear dependence and idiosyncratic risk. These measures are used to determine the extent of AD amongst US stock returns and the market, to obtain an understanding of how AD changes through time and to re-examine the evidence of AD between equity portfolios. By measuring AD separate from linear dependence, I demonstrate several findings. First, I find evidence of non-stationary AD that can exists irrespective of the magnitude of linear dependence, measured by β. This time-varying AD consists of both significant upper tail dependence (UTD) and significant lower tail dependence (LTD), although LTD is found to occur more frequently than UTD, especially for small stocks and stocks displaying high idiosyncratic risk. Significant time-varying AD is also detected between domestic equity indices and international equity markets, implying that if a portfolio is weighted towards certain industries or countries, portfolio construction methods may need to be adjusted in order too meet risk and return targets, particularly if future AD cannot be adequately forecasted. Next, I investigate whether AD is priced in US equities using the Fama and MacBeth (1973) regression methodology in conjunction with my β invariant AD metrics. I find that AD is as important as linear dependence in explaining the variation in returns. In particular, a positive relationship between LTD and return is found. I document an AD risk premium of 2.7% pa, compared to a β risk premium of 6.18% pa. The AD risk premium increases to 6.9% pa for stocks with significant LTD. This result holds after controlling for size, book-to-market ratio, downside β and coskewness. I also find past AD is a significant variable in predicting the future returns of small firms, whilst neither AD nor linear dependence predict the future returns of large firms. I subsequently demonstrate a means of incorporating AD structures during the portfolio construction process using copula functions. I then investigate how asymmetric return dependencies affect the efficient frontier and subsequent portfolio performance under a dynamic rebalancing framework. By considering the problem of tactically allocating a small set of domestic equity indices, I demonstrate several findings. First, I show that a Mean-Variance efficient frontier differs from the efficient frontier constructed under AD. Constructing paper portfolios based upon these differences, I find that real economic value lies in correctly accounting for AD structures. The primary source of this economic value stems from the ability to better protect portfolio value and reduce the size of any erosion in return relative to the normal portfolio. Finally, I document the benefits of actively managing AD during the portfolio construction process and determine a number of portfolio management principles required to successfully manage AD. I illustrate that managing asymmetry risk in a portfolio of international equity indices results in increased return, decreased risk and decreased transaction costs. I show that in order to yield these benefits, investors must actively and dynamically manage their portfolio. Furthermore, I illustrate that the ability to short-sell assets provides most of the benefits described.

Suicide attempts and opioid dependence are important clinical issues, as both are associated with a high degree of psychiatric morbidity and elevated risk of mortality. Research has identified a number of risk factors for suicide attempts among the general population, and to a lesser extent, among heroin users. Due to a lack of case-control studies, however, it is still not known to what extent opioid dependence per se is a risk factor for suicide attempts. This thesis comprised the first study to directly examine whether opioid dependence is a unique risk factor of suicide attempts. This thesis examined suicide attempts, associated risk factors, and related comorbidity among an opioid-dependent case group and a non-opioid-dependent control group. A structured interview was used to collect data from 726 opioid-dependent cases and 399 non-opioid-dependent controls. This thesis identified a number of important findings. Firstly, although opioid-dependent individuals were more likely to report lifetime suicide attempts compared to controls, the risk factors were largely the same for both groups. It appeared that opioid-dependent individuals were characterised by a higher likelihood of the same risk factors for suicide attempts, rather than having different risks. Cases appeared to be at increased risk of suicide attempts because of increased levels of multiple risk factors. Secondly, borderline personality disorder (BPD) and impulsivity were identified as important risk markers for suicidal behaviour, especially among opioid-dependent individuals. The study concluded that the treatment of BPD should be prioritised among this group. Third, self-mutilation was identified as a clinically significant problem in its own right, however, when combined with a history of attempted suicide, the psychological dysfunction observed was found to be very high. Fourth, non-fatal opioid overdose and suicide attempts were found to be distinct behaviours. The risk factors for each were completely different. While drug-related risks were associated with non-fatal overdose, the risk markers for suicide attempts were related to the presence of psychological disorders. This thesis has highlighted important areas of concern for clinical interventions as well as for future research to explore. Considering this is the first study of its kind, future research should focus on its replication.