118 resultados para Buy and hold -menetelmä
Resumo:
This thesis discusses the basic problem of the modern portfolio theory about how to optimise the perfect allocation for an investment portfolio. The theory provides a solution for an efficient portfolio, which minimises the risk of the portfolio with respect to the expected return. A central feature for all the portfolios on the efficient frontier is that the investor needs to provide the expected return for each asset. Market anomalies are persistent patterns seen in the financial markets, which cannot be explained with the current asset pricing theory. The goal of this thesis is to study whether these anomalies can be observed among different asset classes. Finally, if persistent patterns are found, it is investigated whether the anomalies hold valuable information for determining the expected returns used in the portfolio optimization Market anomalies and investment strategies based on them are studied with a rolling estimation window, where the return for the following period is always based on historical information. This is also crucial when rebalancing the portfolio. The anomalies investigated within this thesis are value, momentum, reversal, and idiosyncratic volatility. The research data includes price series of country level stock indices, government bonds, currencies, and commodities. The modern portfolio theory and the views given by the anomalies are combined by utilising the Black-Litterman model. This makes it possible to optimise the portfolio so that investor’s views are taken into account. When constructing the portfolios, the goal is to maximise the Sharpe ratio. Significance of the results is studied by assessing if the strategy yields excess returns in a relation to those explained by the threefactormodel. The most outstanding finding is that anomaly based factors include valuable information to enhance efficient portfolio diversification. When the highest Sharpe ratios for each asset class are picked from the test factors and applied to the Black−Litterman model, the final portfolio results in superior riskreturn combination. The highest Sharpe ratios are provided by momentum strategy for stocks and long-term reversal for the rest of the asset classes. Additionally, a strategy based on the value effect was highly appealing, and it basically performs as well as the previously mentioned Sharpe strategy. When studying the anomalies, it is found, that 12-month momentum is the strongest effect, especially for stock indices. In addition, a high idiosyncratic volatility seems to be positively correlated with country indices on stocks.
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The human striatum is a heterogeneous structure representing a major part of the dopamine (DA) system’s basal ganglia input and output. Positron emission tomography (PET) is a powerful tool for imaging DA neurotransmission. However, PET measurements suffer from bias caused by the low spatial resolution, especially when imaging small, D2/3 -rich structures such as the ventral striatum (VST). The brain dedicated high-resolution PET scanner, ECAT HRRT (Siemens Medical Solutions, Knoxville, TN, USA) has superior resolution capabilities than its predecessors. In the quantification of striatal D2/3 binding, the in vivo highly selective D2/3 antagonist [11C] raclopride is recognized as a well-validated tracer. The aim of this thesis was to use a traditional test-retest setting to evaluate the feasibility of utilizing the HRRT scanner for exploring not only small brain regions such as the VST but also low density D2/3 areas such as cortex. It was demonstrated that the measurement of striatal D2/3 binding was very reliable, even when studying small brain structures or prolonging the scanning interval. Furthermore, the cortical test-retest parameters displayed good to moderate reproducibility. For the first time in vivo, it was revealed that there are significant divergent rostrocaudal gradients of [11C]raclopride binding in striatal subregions. These results indicate that high-resolution [11C]raclopride PET is very reliable and its improved sensitivity means that it should be possible to detect the often very subtle changes occurring in DA transmission. Another major advantage is the possibility to measure simultaneously striatal and cortical areas. The divergent gradients of D2/3 binding may have functional significance and the average distribution binding could serve as the basis for a future database. Key words: dopamine, PET, HRRT, [11C]raclopride, striatum, VST, gradients, test-retest.
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The aim of this thesis was to examine how aquatic organisms, such as fish, behave in an altered environmental condition. Many species of fish use vision as their primary tool to gain information about their surrounding environment. The visual conditions of aquatic habitats are often altered as a result of anthropogenic disturbance, such as eutrophication that initiates algal turbidity. In general, turbidity reduces the visibility and can be hypothesized to have an influence on the behaviour of fish. I used the three-spined stickleback (Gasterosteus aculeatus) as a model species and conducted four studies in the laboratory to test how algal turbidity affects its behaviour. In this thesis, two major behavioural aspects are discussed. The first is antipredator behaviour. In study I, the combined effects of turbidity and shoot density on habitat choice (shelter vs open) behaviour was tested on a group of sticklebacks (20 fish) in the presence and absence of piscivorous perch (Perca fluviatilis). In study II, I examined the behavioural responses of feeding sticklebacks when they were exposed to the sudden appearance of an avian predator (the silhouette of a common tern, Sterna hirundo). The study was done in turbid and clear water using three different groups sizes (1, 3 and 6 fish). The second aspect is foraging behaviour. Study III & IV focused on the effects of algal turbidity on the foraging performance of sticklebacks. In study III, I conducted two separate experiments to examine the effects of turbidity on prey consumption and prey choice of sticklebacks. In this experiment turbidity levels and the proportion of large and small prey (Daphnia spp.) were manipulated. In study IV, I studied whether a group of six sticklebacks can distribute themselves according to food input at two feeding stations in a way that provided each fish with the same amount of food in clear and turbid water. I also observed whether the fish can follow changes in resource distribution between the foraging patches. My results indicate an overall influence of algal turbidity on the antipredator and foraging behaviour of sticklebacks. In the presence of a potential predator, the use of the sheltered habitat was more pronounced at higher turbidity. Besides this, sticklebacks reduced their activity levels with predator presence at higher turbidity and shoot density levels, suggesting a possible antipredator adaptation to avoid a predator. When exposed to a sudden appearance of an avian predator, sticklebacks showed a weaker antipredator response in turbid water, which suggests that turbidity degrades the risk assessment capabilities of sticklebacks. I found an effect of group size but not turbidity in the proportion of sticklebacks that fled to the shelter area, which indicates that sticklebacks are able to communicate among group members at the experimental turbidity levels. I found an overall negative effect of turbidity on food intake. Both turbidity and changes in the proportion of prey sizes played a significant role in a stickleback’s prey selection. At lower turbidity levels (clear <1 and 5 NTU) sticklebacks showed preferences for large prey, whereas in more turbid conditions and when the proportion of large to small prey increased sticklebacks became increasingly random in their prey selection. Finally, my results showed that groups of sticklebacks disperse themselves between feeding stations according to the reward ratios following the predictions of the ideal free distribution theory. However, they took a significantly longer time to reach the equilibrium distribution in turbid water than in clear water. In addition, they showed a slower response to changes in resource distribution in a turbid environment. These findings suggest that turbidity interferes with the information transfer among group foragers. It is important to understand that aquatic animals are often exposed to a degraded environment. The findings of this thesis suggest that algal turbidity negatively affects their behavioural performance. The results also shed light on the underlying behavioural strategies of sticklebacks in turbid conditions that might help them adapt to an altered environmental situation and increase their survival. In conclusion, I hold that although algal turbidity has detrimental effects on the antipredator and foraging behaviour of sticklebacks, their behavioural adjustment might help them adapt to a changing environment.
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The aim of this study was to contribute to the current knowledge-based theory by focusing on a research gap that exists in the empirically proven determination of the simultaneous but differentiable effects of intellectual capital (IC) assets and knowledge management (KM) practices on organisational performance (OP). The analysis was built on the past research and theoreticised interactions between the latent constructs specified using the survey-based items that were measured from a sample of Finnish companies for IC and KM and the dependent construct for OP determined using information available from financial databases. Two widely used and commonly recommended measures in the literature on management science, i.e. the return on total assets (ROA) and the return on equity (ROE), were calculated for OP. Thus the investigation of the relationship between IC and KM impacting OP in relation to the hypotheses founded was possible to conduct using objectively derived performance indicators. Using financial OP measures also strengthened the dynamic features of data needed in analysing simultaneous and causal dependences between the modelled constructs specified using structural path models. The estimates were obtained for the parameters of structural path models using a partial least squares-based regression estimator. Results showed that the path dependencies between IC and OP or KM and OP were always insignificant when analysed separate to any other interactions or indirect effects caused by simultaneous modelling and regardless of the OP measure used that was either ROA or ROE. The dependency between the constructs for KM and IC appeared to be very strong and was always significant when modelled simultaneously with other possible interactions between the constructs and using either ROA or ROE to define OP. This study, however, did not find statistically unambiguous evidence for proving the hypothesised causal mediation effects suggesting, for instance, that the effects of KM practices on OP are mediated by the IC assets. Due to the fact that some indication about the fluctuations of causal effects was assessed, it was concluded that further studies are needed for verifying the fundamental and likely hidden causal effects between the constructs of interest. Therefore, it was also recommended that complementary modelling and data processing measures be conducted for elucidating whether the mediation effects occur between IC, KM and OP, the verification of which requires further investigations of measured items and can be build on the findings of this study.
Resumo:
Active magnetic bearing is a type of bearing which uses magnetic field to levitate the rotor. These bearings require continuous control of the currents in electromagnets and data from position of the rotor and the measured current from electromagnets. Because of this different identification methods can be implemented with no additional hardware. In this thesis the focus was to implement and test identification methods for active magnetic bearing system and to update the rotor model. Magnetic center calibration is a method used to locate the magnetic center of the rotor. Rotor model identification is an identification method used to identify the rotor model. Rotor model update is a method used to update the rotor model based on identification data. These methods were implemented and tested with a real machine where rotor was levitated with active magnetic bearings and the functionality of the methods was ensured. Methods were developed with further extension in mind and also with the possibility to apply them for different machines with ease.
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This dissertation examines parental disciplinary violence against children in authority records and in the criminal procedure in Finland. The main aim is to analyze disciplinary violence, how it is defined, and how it is constructed as a crime by social workers, the police, and parents. This dissertation consists of four sub-studies and a summary article. In the first sub-study, I examine how disciplinary violence appears in child welfare documents and analyze the decision-making processes and measures taken by the child welfare workers. The second sub-study, utilizing police interview data, examines police officers’ perceptions of disciplinary violence, its criminalization, and its investigation. In addition to this analysis of police officers’ own perceptions, in the third sub-study, I use reports of crime and pre-trial investigation documents to look at what a typical suspicion of disciplinary violence coming to the attention of the police is and examine the decision-making processes of the police. Utilizing authority data, the fourth sub-study analyzes how parents rationalize the use of disciplinary violence to the authorities investigating these suspicions. The research provides findings that are unprecedented in Finland. Firstly, it was shown that social workers’ decision-making processes in suspicions of disciplinary violence follow three pathways of reasoning, with many factors taken into consideration; and in less than one-third of the cases, a request for criminal investigation has been made to the police. Secondly, it was verified that police officers hold different perceptions of disciplinary violence, and these perceptions have multiple effects on the investigation of these cases and the construction of disciplinary violence as a crime. Thirdly, the analysis of the reports of crime and pre-trial investigation documents showed that almost two-thirds of the cases of disciplinary violence had been sent to a prosecutor by the police and, thus, defined as a crime. However, in many cases, acts of disciplinary violence were often seen as ‘educational, petty one-off incidents’ and a possible trial and punishment for the perpetrator were seen as unreasonable. Fourthly, it was found that parents often try to neutralize and rationalize the violence they have used against their children, for example, either by denying the victim, the criminal intent, or the entire act, or relying on the necessity of the forbidden act. The dissertation concludes that disciplinary violence is defined and constructed in authority policies and practices, first and foremost, by the severity of the act, the nature of the act as continuous or singular, the perceived harm caused by the act to a child, and the perceptions of authorities regarding physical punishment of children. The asymmetrical power setting present in disciplinary violence and parents’ legitimized right to raise and discipline their children partly seem to explain why criminal-law processing of these suspicions of violence and understanding these as crimes is difficult. Finally, this research calls for more coherent and consistent authority practices and policies, achieved by educating authorities and increasing awareness on disciplinary violence, questions the need for a concept like ‘disciplinary’ violence, and suggests more emphasis on unambiguous perceptions of a child’s best interest.
Resumo:
SUMMARY Organizational creativity – hegemonic and alternative discourses Over the course of recent developments in the societal and business environment, the concept of creativity has been brought into new arenas. The rise of ‘creative industries’ and the idea of creativity as a form of capital have attracted the interests of business and management professionals – as well as academics. As the notion of creativity has been adopted in the organization studies literature, the concept of organizational creativity has been introduced to refer to creativity that takes place in an organizational context. This doctoral thesis focuses on organizational creativity, and its purpose is to explore and problematize the hegemonic organizational creativity discourse and to provide alternative viewpoints for theorizing about creativity in organizations. Taking a discourse theory approach, this thesis, first, provides an outline of the currently predominant, i.e. hegemonic, discourse on organizational creativity, which is explored regarding themes, perspectives, methods and paradigms. Second, this thesis consists of five studies that act as illustrations of certain alternative viewpoints. Through these exemplary studies, this thesis sheds light on the limitations and taken-for-granted aspects of the hegemonic discourse and discusses what these alternative viewpoints could offer for the understanding of and theorizing for organizational creativity. This study leans on an assumption that the development of organizational creativity knowledge and the related discourse is not inevitable or progressive but rather contingent. The organizational creativity discourse has developed in a certain direction, meaning that some themes, perspectives, and methods, as well as assumptions, values, and objectives, have gained a hegemonic position over others, and are therefore often taken for granted and considered valid and relevant. The hegemonization of certain aspects, however, contributes to the marginalization of others. The thesis concludes that the hegemonic discourse on organizational creativity is based on an extensive coverage of certain themes and perspectives, such as those focusing on individual cognitive processes, motivation, or organizational climate and their relation to creativity, to name a few. The limited focus on some themes and the confinement to certain prevalent perspectives, however, results in the marginalization of other themes and perspectives. The negative, often unintended, consequences, implications, and side effects of creativity, the factors that might hinder or prevent creativity, and a deeper inquiry into the ontology and epistemology of creativity have attracted relatively marginal interest. The material embeddedness of organizational creativity, in other words, the physical organizational environment as well as the human body and its non-cognitive resources, has largely been overlooked in the hegemonic discourse, although thereare studies in this area that give reason to believe that they might prove relevant for the understanding of creativity. The hegemonic discourse is based on an individual-centered understanding of creativity which overattributes creativity to an individual and his/her cognitive capabilities, while simultaneously neglecting how, for instance, the physical environment, artifacts, social dynamics and interactions condition organizational creativity. Due to historical reasons, quantitative as well as qualitative yet functionally- oriented studies have predominated the organizational creativity discourse, although studies falling into the interpretationist paradigm have gradually become more popular. The two radical paradigms, as well as methodological and analytical approaches typical of radical research, can be considered to hold a marginal position in the field of organizational creativity. The hegemonic organizational creativity discourse has provided extensive findings related to many aspects of organizational creativity, although the con- ceptualizations and understandings of organizational creativity in the hegemonic discourse are also in many respects limited and one-sided. The hegemonic discourse is based on an assumption that creativity is desirable, good, necessary, or even obligatory, and should be encouraged and nourished. The conceptualiza- tions of creativity favor the kind of creativity which is useful, valuable and can be harnessed for productivity. The current conceptualization is limited to the type of creativity that is acceptable and fits the managerial ideology, and washes out any risky, seemingly useless, or negative aspects of creativity. It also limits the possible meanings and representations that ‘creativity’ has in the respective discourse, excluding many meanings of creativity encountered in other discourses. The excessive focus on creativity that is good, positive, productive and fits the managerial agenda while ignoring other forms and aspects of creativity, however, contributes to the dilution of the notion. Practices aimed at encouraging the kind of creativity may actually entail a risk of fostering moderate alterations rather than more radical novelty, as well as management and organizational practices which limit creative endeavors, rather than increase their likelihood. The thesis concludes that although not often given the space and attention they deserve, there are alternative conceptualizations and understandings of organizational creativity which embrace a broader notion of creativity. The inability to accommodate the ‘other’ understandings and viewpoints within the organizational creativity discourse runs a risk of misrepresenting the complex and many-sided phenomenon of creativity in organizational context. Keywords: Organizational creativity, creativity, organization studies, discourse theory, hegemony
Resumo:
In this study, finite element analyses and experimental tests are carried out in order to investigate the effect of loading type and symmetry on the fatigue strength of three different non-load carrying welded joints. The current codes and recommendations do not give explicit instructions how to consider degree of bending in loading and the effect of symmetry in the fatigue assessment of welded joints. The fatigue assessment is done by using effective notch stress method and linear elastic fracture mechanics. Transverse attachment and cover plate joints are analyzed by using 2D plane strain element models in FEMAP/NxNastran and Franc2D software and longitudinal gusset case is analyzed by using solid element models in Abaqus and Abaqus/XFEM software. By means of the evaluated effective notch stress range and stress intensity factor range, the nominal fatigue strength is assessed. Experimental tests consist of the fatigue tests of transverse attachment joints with total amount of 12 specimens. In the tests, the effect of both loading type and symmetry on the fatigue strength is studied. Finite element analyses showed that the fatigue strength of asymmetric joint is higher in tensile loading and the fatigue strength of symmetric joint is higher in bending loading in terms of nominal and hot spot stress methods. Linear elastic fracture mechanics indicated that bending reduces stress intensity factors when the crack size is relatively large since the normal stress decreases at the crack tip due to the stress gradient. Under tensile loading, experimental tests corresponded with finite element analyzes. Still, the fatigue tested joints subjected to bending showed the bending increased the fatigue strength of non-load carrying welded joints and the fatigue test results did not fully agree with the fatigue assessment. According to the results, it can be concluded that in tensile loading, the symmetry of joint distinctly affects on the fatigue strength. The fatigue life assessment of bending loaded joints is challenging since it depends on whether the crack initiation or propagation is predominant.
Resumo:
Tämä tutkielma käsittelee paikkamarkkinointia ja paikkabrändäystä. Tutkielmassa tarkastellaan paikallisen ja turistin tapoja muodostaa kaupunkibrändi; mistä palasista brändi muodostuu kirjallisuuden ja haastateltavien mukaan, koetaanko eri palaset vaihtelevissa määrin tärkeiksi riippuen siitä, tarkastellaanko paikkaa paikallisena vai turistina, ja löytyykö jotain yhteisiä retorisia nimittäjiä sille, miten kotikaupungista puhutaan verrattuna lomakaupunkiin. Tutkimuksessa haastateltiin yli kolmeakymmentä henkilöä heidän kotikaupungeistaan ja kaupungeista, joihin he olivat matkustaneet lomalle. Haastateltavat olivat suurinpiirtein samanikäisiä, mutta eri kaupungeista ja matkustaneet eri paikkoihin. Haastateltavia pyydettiin ensin kuvailemaan vapaasti kotikaupunkiaan ja sen jälkeen kaupungista kysyttiin kirjallisuuteen perustuen kysymyksiä. Sama menetelmä toistettiin lomakohteen suhteen. Tutkimuksesta selvisi, että paikkabrändi muodostetaan samoista komponenteista, mutta joidenkin komponenttien merkitys on tärkeämpi kotikaupungissa, kun taas toiset komponentit ovat tärkeitä lomakohteen suhteen. Ihmiset ja kulttuuri yleisesti koettiin tärkeinä komponentteina molemmista paikkabrändeistä puhuttaessa, kun taas kotikaupungin brändinmuodostukseen kuului vahvemmin lait ja muut käytännölliset menettelytavat kuten liikenteen toimivuus. Lomakohteen brändinmuodostuksessa vapaudella tehdä mitä haluaa oli suuri merkitys ja vapautta nähtiin eri muodoissa. Retoriikka kotikaupungista puhuttaessa oli selvästi negatiivista, kun taas lomakohteesta puhuttiin yleisesti ottaen positiiviseen sävyyn. Suhde kotikaupunkiin oli ambivalentti, sillä huonojakin puolia mainittaessa niitä puolusteltiin, tai kotikaupungista mainittiin loppujen lopuksi jotain hyvää. Tutkimusten tuloksiin perustuen toimenpidesuosituksina ehdotetaan olemassaolevan autenttisen kulttuurin ylläpitämäistä, korostamista ja kaupungin orgaanista kehittämistä suuntaan, jossa se on hyvä paikka niin elämiseen kuin lomailuun. Identiteetti, imago ja ihmiset kietoutuvat tiiviisti yhteen, minkä vuoksi kaupunkisuunnittelun- ja kehittämisen tehtävänä on pitää huolta, että kaupunki on onnistunut molempien ryhmien suhteen, ja molemmat ryhmät levittävät kaupungista positiivista sanomaa.
Resumo:
The aim of this Master’s thesis is to find a method for classifying spare part criticality in the case company. Several approaches exist for criticality classification of spare parts. The practical problem in this thesis is the lack of a generic analysis method for classifying spare parts of proprietary equipment of the case company. In order to find a classification method, a literature review of various analysis methods is required. The requirements of the case company also have to be recognized. This is achieved by consulting professionals in the company. The literature review states that the analytic hierarchy process (AHP) combined with decision tree models is a common method for classifying spare parts in academic literature. Most of the literature discusses spare part criticality in stock holding perspective. This is relevant perspective also for a customer orientated original equipment manufacturer (OEM), as the case company. A decision tree model is developed for classifying spare parts. The decision tree classifies spare parts into five criticality classes according to five criteria. The criteria are: safety risk, availability risk, functional criticality, predictability of failure and probability of failure. The criticality classes describe the level of criticality from non-critical to highly critical. The method is verified for classifying spare parts of a full deposit stripping machine. The classification can be utilized as a generic model for recognizing critical spare parts of other similar equipment, according to which spare part recommendations can be created. Purchase price of an item and equipment criticality were found to have no effect on spare part criticality in this context. Decision tree is recognized as the most suitable method for classifying spare part criticality in the company.
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Globalization and the developments of supply chain have made inexpensive labor and the low production costs of developing countries available to businesses worldwide. Unfortunately, these developments have also led to the exploitation of human and natural resources. The increasing supply of cheap and fashionable clothing has created a contradiction between consumers’ concerns for sustainability and their purchase behavior in the fashion industry. Since the uncovering of several sweatshop scandals in the 1980’s and 1990’s ethical fashion brands have started to emerge. Ethical fashion has sparked the interest of consumers and studies have shown promising positive attitudes towards it. However, these attitudes have failed to translate into action and purchase behavior of ethical fashion has not reached the expectations. In order to translate the positive attitudes into buying companies must understand consumer’s motivations and reasons behind the purchase decision. The objective of this study is to understand the antecedents behind young consumer’s purchase intention of ethical fashion. The study is based on the theory of planned behavior which has been widely used to study consumer behavior and purchase decisions. The theory has also been used in ethical decision-making and fashion context before. According to the theory, in order to understand purchase intentions consumer’s attitudes toward buying ethical fashion were studied. The theory also states that attitudes are formed from beliefs, thus, consumer’s beliefs about the fashion industry were studied. To contribute to existing research, the effect of sweatshop issues and environmental issues were compared. The data was collected from university students (n=617) with an online survey. The results were analyzed by statistical methods and they revealed that young Finnish consumers hold positive attitudes towards buying ethical fashion as well as positive purchase intentions of ethical fashion. A strong relationship was found between positive attitudes and positive purchase intentions. Also, the more negative consumers’ beliefs of the fashion industry were the more positive their attitudes toward buying ethical fashion were. In contradiction to previous research this study revealed that environmental issues had greater effect on attitudes than sweatshop issues. Interesting differences between consumers were found depending on their field of education. Students from humanities and social sciences held the most negative beliefs as well as most positive attitudes and purchase intentions of ethical fashion.
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ABSTRACT Fescues consist of wild and cultivated grasses that have adapted to a wide range of environmental conditions. They are an excellent model species for evolutionary ecology studies that investigate symbiosis and polyploidization and their effects on plant performance. First, they are frequently infected with symbiotic endophytic fungi known to affect a plant’s ability to cope with biotic and abiotic environmental factors. Second, fescue species have been reported to have substantial intraspecific variation in their ploidy level and morphology. In my thesis, I examined large-scale generalizations for frequency of polyploidy and endophyte infections and their effects on plant morphology. As a model species, I selected red (Festuca rubra) and viviparous sheep’s (F. vivipara) fescues. They are closely related, but they differ in terms of distribution and endophyte infection frequency. I investigated the biogeographic pattern and population biology of 29 red and 12 viviparous sheep’s fescue populations across ≈300 latitudes in Europe (400-690 N). To examine plant ploidy levels, I implemented time- and cost-efficient plate-based high throughput flow cytometric analysis. This efficient procedure enabled me to analyze over 1000 red fescue individuals. I found three ploidy levels among them: overall 84 %, 9 % and 7 % of the red fescue plants were hexaploid, tetraploid and octoploid, respectively. However, all viviparous sheep’s fescue plants were tetraploid. Ploidy level of red fescue appeared to some extent follow gradients in latitude and primary production as suggested by previous studies, but these results could be explained better by taking the sampling design and local adaptation into account. Three Spanish populations were mostly tetraploids and one high elevation population in northernmost Finland (Halti) was octoploid, while most other populations (25 sites) were dominated by hexaploids. Endophyte infection frequencies of wild fescue populations varied from 0 to 81 % in red fescue populations and from 0 to 30 % in viviparous sheep’s fescue populations. No gradients with latitude or primary production of the sites were detected. As taxonomy of red fescues is somewhat unclear, I also studied morphology, ploidy variation and endophyte status of proposed subspecies of European red fescues. Contrary to previous literature, different ploidy levels occurred in the same subspecies. In addition to wild fescues, I also used two agronomically important cultivars of meadow and tall fescue (Schedonorus phoenix and S. pratensis). As grass-legume mixtures have an agronomic advantage over monocultures in meadows, I carried out a mixture/competition experiment with fescues and red clover to find that species composition, nutrient availability and endophyte status together determined the total biomass yield that was higher in mixtures compared to monocultures. The results of this thesis demonstrate the importance of local biotic and abiotic factors such as grazing gradients and habitat types, rather than suggested general global geographical or environmental factors on grass polyploidization or its association with symbiotic endophytic fungi. I conclude that variation in endophyte infection frequencies and ploidy levels of wild fescues support the geographic mosaic theory of coevolution. Historical incidents, e.g., glaciation and present local factors, rather than ploidy or endophyte status, determine fescue morphology.
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There is an increasing demand for individualized, genotype-based health advice. The general population-based dietary recommendations do not always motivate people to change their life-style, and partly following this, cardiovascular diseases (CVD) are a major cause of death in worldwide. Using genotype-based nutrition and health information (e.g. nutrigenetics) in health education is a relatively new approach, although genetic variation is known to cause individual differences in response to dietary factors. Response to changes in dietary fat quality varies, for example, among different APOE genotypes. Research in this field is challenging, because several non-modifiable (genetic, age, sex) and modifiable (e.g. lifestyle, dietary, physical activity) factors together and with interaction affect the risk of life-style related diseases (e.g. CVD). The other challenge is the psychological factors (e.g. anxiety, threat, stress, motivation, attitude), which also have an effect on health behavior. The genotype-based information is always a very sensitive topic, because it can also cause some negative consequences and feelings (e.g. depression, increased anxiety). The aim of this series of studies was firstly to study how individual, genotype-based health information affects an individual’s health form three aspects, and secondly whether this could be one method in the future to prevent lifestyle-related diseases, such as CVD. The first study concentrated on the psychological effects; the focus of the second study was on health behavior effects, and the third study concentrated on clinical effects. In the fourth study of this series, the focus was on all these three aspects and their associations with each other. The genetic risk and health information was the APOE gene and its effects on CVD. To study the effect of APOE genotype-based health information in prevention of CVD, a total of 151 volunteers attended the baseline assessments (T0), of which 122 healthy adults (aged 20 – 67 y) passed the inclusion criteria and started the one-year intervention. The participants (n = 122) were randomized into a control group (n = 61) and an intervention group (n = 61). There were 21 participants in the intervention Ɛ4+ group (including APOE genotypes 3/4 and 4/4) and 40 participants in the intervention Ɛ4- group (including APOE genotypes 2/3 and 3/3). The control group included 61 participants (including APOE genotypes 3/4, 4/4, 2/3, 3/3 and 2/2). The baseline (T0) and follow-up assessments (T1, T2, T3) included detailed measurements of psychological (threat and anxiety experience, stage of change), and behavioral (dietary fat quality, consumption of vegetables, - high fat/sugar foods and –alcohol, physical activity and health and taste attitudes) and clinical factors (total-, LDL- HDL cholesterol, triglycerides, blood pressure, blood glucose (0h and 2h), body mass index, waist circumference and body fat percentage). During the intervention six different communication sessions (lectures on healthy lifestyle and nutrigenomics, health messages by mail, and personal discussion with the doctor) were arranged. The intervention groups (Ɛ4+ and Ɛ4-) received their APOE genotype information and health message at the beginning of the intervention. The control group received their APOE genotype information after the intervention. For the analyses in this dissertation, the results for 106/107 participants were analyzed. In the intervention, there were 16 participants in the high-risk (Ɛ4+) group and 35 in the low-risk (Ɛ4-) group. The control group had 55 participants in studies III-IV and 56 participants in studies I-II. The intervention had both short-term (≤ 6 months) and long-term (12 months) effects on health behavior and clinical factors. The short-term effects were found in dietary fat quality and waist circumference. Dietary fat quality improved more in the Ɛ4+ group than the Ɛ4- and the control groups as the personal, genotype-based health information and waist circumference lowered more in the Ɛ4+ group compared with the control group. Both these changes differed significantly between the Ɛ4+ and control groups (p<0.05). A long-term effect was found in triglyceride values (p<0.05), which lowered more in Ɛ4+ compared with the control group during the intervention. Short-term effects were also found in the threat experience, which increased mostly in the Ɛ4+ group after the genetic feedback (p<0.05), but it decreased after 12 months, although remaining at a higher level compared to the baseline (T0). In addition, Study IV found that changes in the psychological factors (anxiety and threat experience, motivation), health and taste attitudes, and health behaviors (dietary, alcohol consumption, and physical activity) did not directly explain the changes in triglyceride values and waist circumference. However, change caused by a threat experience may have affected the change in triglycerides through total- and HDL cholesterol. In conclusion, this dissertation study has given some indications that individual, genotypebased health information could be one potential option in the future to prevent lifestyle-related diseases in public health care. The results of this study imply that personal genetic information, based on APOE, may have positive effects on dietary fat quality and some cardiovascular risk markers (e.g., improvement in triglyceride values and waist circumference). This study also suggests that psychological factors (e.g. anxiety and threat experience) may not be an obstacle for healthy people to use genotype-based health information to promote healthy lifestyles. However, even in the case of very personal health information, in order to achieve a permanent health behavior change, it is important to include attitudes and other psychological factors (e.g. motivation), as well as intensive repetition and a longer intervention duration. This research will serve as a basis for future studies and its information can be used to develop targeted interventions, including health information based on genotyping that would aim at preventing lifestyle diseases. People’s interest in personalized health advices has increased, while also the costs of genetic screening have decreased. Therefore, generally speaking, it can be assumed that genetic screening as a part of the prevention of lifestyle-related diseases may become more common in the future. In consequence, more research is required about how to make genetic screening a practical tool in public health care, and how to efficiently achieve long-term changes.