31 resultados para Protection of Privacy


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Valtion rajat ylittävät terveyspalvelut Euroopan unionissa sekä Euroopan unionin säädösten merkitys ja vaikutus erityisesti lääkejakeluun ja verenluovuttajille jaettavaan tiedotusaineistoon Valtion rajat ylittävä terveydenhuolto on suuren kiinnostuksen kohteena Euroopan unionissa. Resurssien hyödyntäminen parhaalla mahdollisella tavalla ja tiedon keskittäminen ovat tarpeen terveydenhuollon kustannusten alati noustessa. Terveydenhuoltopalvelut kuuluvat Euroopan sisämarkkinoiden vapaan liikkuvuuden piiriin. Euroopan unionilla ei ole kuitenkaan toimivaltaa säädellä terveydenhuoltojärjestelmiä, vaan sen mahdollisuudet ovat enimmäkseen kansanterveyden edistämisessä ja suojelussa, myös muilla toimialueilla kuin terveydenhuollossa. Tutkimuksen tavoitteena oli tutkia Euroopan unionin säädösten vaikutusta terveydenhuoltosektoriin, erityisesti valtion rajat ylittäviin terveydenhuoltopalveluihin. Erityiskohteena olivat lääkemääräyksen toimittaminen toisen Euroopan unionin jäsenmaan apteekista, resepti-lääkkeiden maahantuonti omaan henkilökohtaiseen käyttöön, sähköisen lääkemääräyksen käyttö kansallisesti ja mahdollisuudet sen käyttöön eri jäsenmaiden välillä, online-apteekkien soveltuvuus Euroopan unionin sisämarkkinoille sekä verenluovuttajille jaettavan tiedotusaineiston yhtenäistämistarve Euroopan unionin alueella. Tutkimuksen osa-alueiden aineisto koottiin vuosina 1999–2003, jolloin Euroopan unioniin kuului 15 jäsenmaata. Apteekit toimittivat useimmiten myös ei-kansalliset, toisessa Euroopan unionin jäsenmaassa annetut lääkemääräykset. Kaikki jäsenmaat rajoittivat lääkemääräyksen vaativien lääkkeiden maahantuontia. Rajoituksia oli maahantuontimäärissä ja -tavoissa. Lisäksi sairasvakuutuskorvausten saaminen ulkomailla lunastetuista reseptilääkkeistä oli hankalaa. Sähköiset lääkemääräykset olivat käytössä vain kahdessa maassa, mutta useissa maissa suunniteltiin niiden kokeilua. Standardit ja käyttöjärjestelmät olivat erilaisia eri maissa. Euroopan unionin alueelle on perustettu online-apteekkeja, joiden toiminta on kuitenkin vaatimatonta. Verenluovuttajille annettava tiedotusaineisto ei missään maassa täyttänyt veridirektiivin vaatimuksia. Tutkimuksen tulokset osoittivat kansallisten käytäntöjen eroavaisuuksien rajoittavan valtion rajat ylittäviä terveydenhuoltopalveluita. Vaikka Euroopan unionin tavoitteena ei ole yhtenäistää terveydenhuoltojärjestelmiä, on tarpeen arvioida uudelleen unionin ja jäsenmaiden välistä työnjakoa. Kansalliset terveydenhuoltojärjestelmät eivät ole erillään Euroopan sisämarkkinoista, jotka merkittävästi vaikuttavat terveydenhuoltoon.

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Ihmisen toiminnan vaikutus ilmakehään johtaa todennäköisesti ilmastonmuutoksiin. Eräs näistä muutoksista on maapallon keskilämpötilan nousu, joka aiheutuu kasvihuonekaasujen lisääntyneestä pitoisuudesta ilmakehässä. Vaikutusten vähentämiseksi on hiilidioksidipäästöjä vähennettävä. Kioton pöytäkirja asettaa allekirjoittaneille maille päästövelvoitteet. Euroopan unionin tulee vähentää kasvihuonekaasupäästöjään 8%:lla. Eräs vähennysmekanismeista on päästökauppa. Päästökauppa on sekä keino suojella ympäristöä että ympäristöpoliittinen instrumentti kasvihuonekaasupäästövähennysten kustannusten keventämiseksi. Päästökauppa ei suoranaisesti vähennä kasvihuonekaasupäästöjä, vaan tasaa niitä maiden ja laitosten välillä. Uusiutuvan energian käytön edistäminen sekä kansainvälisesti että kansallisesti johtaa suoriin kasvihuonekaasupäästöjen vähenemiseen. Euroopan unionin jäsenvaltiot ovat asettaneet kansalliset viitearvot uusituvan sähkön kulutukselle. Saavuttaakseen nämä viitearvot maiden tulee tukea uusiutuvia energialähteitä eri menetelmin kuten vihreillä sertifikaateilla. Päästökauppa ja kaupattavat vihreät sertifikaatit tulevat vaikuttamaan energiantuottajien liiketoimintaan. Työssä on tutkittu päästökaupan ja vihreiden sertifikaattien vaikutuksia Vattenfall Kaukolämpö Oy:n, Vattenfall Sähköntuotanto Oy:n ja Vamy Oy:n liiketoimintaan.

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High barrier materiaaleilla pyritään pidentämään pakattujen elintarvikkeiden hyllyikää. Barrierin tärkein tehtävä on elintarvikkeen suojaaminen hapelta ja kosteudelta. Alumiinin käyttöä barriermateriaalina pyritään vähentämään korvaamalla alumiini polymeereillä, jotka täyttävät elintarvikkeiden asettamat korkeat säilyvyysvaatimukset. Etyylivinyylialkoholin (EVOH) hapenläpäisevyys on kuivissa olosuhteissa alhaisin kaupallisista muovilaaduista. EVOH tarjoaa myös erinomaisen suojan muita kaasuja, rasvoja, hajuja ja aromeja vastaan ja sitä on helppo prosessoida. Polyamideilla on erinomainen kaasutiiveys sekä hyvä lujuus ja sitkeys. Eri muovilaatuja sekoittamalla voidaan vähentää hapenläpäisyä ja parantaa prosessointia. Polyolefiineja käytetään yleisesti päällystysmateriaaleina, koska ne suojaavat tuotetta erinomaisesti kosteudelta. Hapenläpäisyllä tarkoitetaan hapen kulkeutumista materiaalin läpi joko permeaation kautta tai reikien ja vuotojen läpi. Kaasun permeoitumiseen materiaalin läpi vaikuttavat materiaalin vapaa tilavuus, kiteisyysaste, orientaatio, substituointi, suhteellinen kosteus, lämpötila, barrierkerroksen paksuus, paine-ero ja permeoituvan molekyylin ominaisuudet. Kokeellisessa osassa analysoitiin ja vertailtiin kartonkipohjaisia mehutölkkejä, joissa käytettävät high barrier materiaalit olivat EVOH ja PA. Kartonkipohjaisia alumiinitölkkejä käytettiin referenssinä. Pakkausten hapenläpäisevyysmittauksissa saatiin samasta näytteestä toistettavia tuloksia, vaikka vuotomittauksissa saadut tulokset eivät olleet vertailukelpoisia hapenläpäisytulosten kanssa. Tölkkien valmistus vaikutti oleellisesti pakkausten tiiveysominaisuuksiin. Hapenläpäisy vuotojen ja reikien läpi oli merkittävämpää kuin hapenläpäisy materiaalin läpi. Pakkausten tiiveysominaisuuksia analysoitiin mittaamalla appelsiinimehun askorbiini-happopitoisuus. Askorbiinihapon hajoaminen mitattiin koetölkkeihin pakatusta appelsiinimehusta, ja lämpötilan, valon ja hapen vaikutusta askorbiinihapon hajoamiseen tutkittiin 12 viikon ajan. Lämpötilalla oli suurin vaikutus askorbiinihapon hajoamiseen huolimatta käytetystä pakkausmateriaalista.

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Tässä luomistyössä on esitetty tutkimus informaation suojaamisen menetelmien osalta paikallisissa ja ryhmäkuntaisissa verkoissa. Tutkimukseen kuuluu nykyaikaisten kryptagraafisten järjestelmien, Internetin/Intranetin ohjelmointikeinojen ja pääsyoikeuksien jakelumenetelmien analyysi. Tutkimusten perusteella on laadittu ohjelmiston prototyyppi HTML-tiedostojen suojaamista varten. Ohjelmiston laatimisprosessi on sisältänyt vaatimusten, järjestelmän ja suojelukomponenttien suunnittelun ja protytyypin testauksen. Ohjelmiston realisoinnin jälkeen kirjoitettiin käyttöohjeet. Ohjelmiston prototyyppi suojaa informaatiota HTML-tiedoston koko käytön aikana ja eri yrityksissä voidaan käyttää sitä pienien laajennuksien jälkeen.

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Once the seed has germinated, the plant is forced to face all the environmental changes in its habitat. In order to survive, plants have evolved a number of different acclimation systems. The primary reaction behind plant growth and development is photosynthesis. Photosynthesis captures solar energy and converts it into chemical form. Photosynthesis in turn functions under the control of environmental cues, but is also affected by the growth, development, and metabolic state of a plant. The availability of solar energy fluctuates continuously, requiring non-stop adjustment of photosynthetic efficiency in order to maintain the balance between photosynthesis and the requirements and restrictions of plant metabolism. Tight regulation is required, not only to provide sufficient energy supply but also to prevent the damage caused by excess energy. The very first reaction of photosynthesis is splitting of water into the form of oxygen, hydrogen, and electrons. This most fundamental reaction of life is run by photosystem II (PSII), and the energy required for the reaction is collected by the light harvesting complex II (LHCII). Several proteins of the PSII-LHCII complex are reversibly phosphorylated according to the energy balance between photosynthesis and metabolism. Thylakoid protein phosphorylation has been under extensive investigation for over 30 years, yet the physiological role of phosphorylation remains elusive. Recently, the kinases behind the phosphorylation of PSII-LHCII proteins (STN7 and STN8) were identified and the knockout mutants of these kinases became available, providing powerful tools to elucidate the physiological role of PSII-LHCII phosphorylation. In my work I have used the stn7 and stn8 mutants in order to clarify the role of PSII-LHCII phosphorylation in regulation and protection of the photosynthetic machinery according to environmental cues. I show that STN7- dependent PSII-LHCII protein phosphorylation is required to balance the excitation energy distribution between PSII and PSI especially under low light intensities when the excitation energy transfer from LHC to PSII and PSI is efficient. This mechanism differs from traditional light quality-induced “state 1” – “state 2” transition and ensures fluent electron transfer from PSII to PSI under low light, yet having highest physiological relevance under fluctuating light intensity. STN8-dependent phosphorylation of PSII proteins, in turn, is required for fluent turn-over of photodamaged PSII complexes and has the highest importance upon prolonged exposure of the photosynthetic apparatus to excess light.

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The most important knowledge in firms is mostly tacit and embedded in individuals within the organization. This background knowledge that firms possess is used for creation of new knowledge and innovations. As firms today greatly concentrate on their core competencies, they need external knowledge from various collaboration partners. Thus, collaborative relationship governance, as well as control (use of appropriability mechanisms) over background (the input from each firm in innovative activities) and foreground knowledge (the output of collaboration activities) is needed in order to successfully create and capture value from innovative activities without losing core knowledge and competitiveness. Even though research has concentrated on knowledge protection and knowledge sharing, studies that combine both of these views and examine the effects of sharing and protection on value creation and capture have been rather limited. Studies have mainly focused on the protection of the output of innovation while forgetting the protection of the input of innovation. On the other hand, as the research concentrating on the output of innovation tends to favor formal mechanisms, informal mechanisms have remained more unknown to researchers as well as managers. This research aims to combine the perspectives of knowledge sharing and knowledge protection and their relationship with value creation and value capture. The sharing and protection are viewed from two points of view: the use of appropriability mechanisms, as well as governance of the collaborative relationship. The study consists of two parts. The first part introduces the research topic and discusses the overall results. The second part comprises six complementary research publications. Both qualitative and quantitative research methods are used in the study. In terms of results, the findings enhance understanding of the combined use of formal and informal mechanisms for knowledge protection and sharing. Informal mechanisms appear to be emphasized in the protection of background knowledge, and thus are prerequisites for innovation, whereas formal mechanisms are relied on more for protecting the results of innovative activities. However, the simultaneous use of the formal and informal mechanisms that are relevant to the particular industry and innovation context is recommendedthroughout the collaborative innovation process. Further, the study adds to the current knowledge on HRM as an appropriability mechanism: on the firm level its uses include assessing and hedging against employee-related risks such as knowledge leaking and knowledge leaving. A further contribution is to the research on HRM protection and its interrelations with other appropriability mechanisms, its constituents, and its potential use in the area of knowledge protection.

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The objective of this study is to explore how the Open Innovation paradigm is applied in by small and medium-size enterprises in Russia. The focus of the study is to understand how the processes of research and development and commercialization proceed in these kind of companies and to which extent they apply open innovation principles. Russian leadership makes certain steps for transition from the export of raw materials to an innovative model of economic growth. The research aims to disclose actual impact of these attempts. The closed innovation model and the erosion factors which lead to the destruction of an old one and emergence of new model are described. Features of open innovation implementation and intellectual property rights protection in small and medium enterprises are presented. To achieve the objective, a qualitative case study approach was chosen. Research includes facts and figures, views and opinions of management of studied companies related to innovation process in the company and in Russia in general. The research depicts the features of Open Innovation implementation by SMEs in Russia. A large number of research centers with necessary equipment and qualified personnel allow case companies to use external R&D effectively. They cooperate actively with research institutes, universities and laboratories. Thus, they apply inbound Open Innovation. On the contrary, lack of venture capital, low demand for technologies within the domestic market and weak protection of intellectual property limit the external paths to new markets. Licensing-out and creation of spin-off are isolated cases. Therefore, outbound Open Innovation is not a regular practice.

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Poster at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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Macroalgae are the main primary producers of the temperate rocky shores providing a three-dimensional habitat, food and nursery grounds for many other species. During the past decades, the state of the coastal waters has deteriorated due to increasing human pressures, resulting in dramatic changes in coastal ecosystems, including macroalgal communities. To reverse the deterioration of the European seas, the EU has adopted the Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD), aiming at improved status of the coastal waters and the marine environment. Further, the Habitats Directive (HD) calls for the protection of important habitats and species (many of which are marine) and the Maritime Spatial Planning Directive for sustainability in the use of resources and human activities at sea and by the coasts. To efficiently protect important marine habitats and communities, we need knowledge on their spatial distribution. Ecological knowledge is also needed to assess the status of the marine areas by involving biological indicators, as required by the WFD and the MSFD; knowledge on how biota changes with human-induced pressures is essential, but to reliably assess change, we need also to know how biotic communities vary over natural environmental gradients. This is especially important in sea areas such as the Baltic Sea, where the natural environmental gradients create substantial differences in biota between areas. In this thesis, I studied the variation occurring in macroalgal communities across the environmental gradients of the northern Baltic Sea, including eutrophication induced changes. The aim was to produce knowledge to support the reliable use of macroalgae as indicators of ecological status of the marine areas and to test practical metrics that could potentially be used in status assessments. Further, the aim was to develop a methodology for mapping the HD Annex I habitat reefs, using the best available data on geology and bathymetry. The results showed that the large-scale variation in the macroalgal community composition of the northern Baltic Sea is largely driven by salinity and exposure. Exposure is important also on smaller spatial scales, affecting species occurrence, community structure and depth penetration of algae. Consequently, the natural variability complicates the use of macroalgae as indicators of human-induced changes. Of the studied indicators, the number of perennial algal species, the perennial cover, the fraction of annual algae, and the lower limit of occurrence of red and brown perennial algae showed potential as usable indicators of ecological status. However, the cumulated cover of algae, commonly used as an indicator in the fully marine environments, showed low responses to eutrophication in the area. Although the mere occurrence of perennial algae did not show clear indicator potential, a distinct discrepancy in the occurrence of bladderwrack, Fucus vesiculosus, was found between two areas with differing eutrophication history, the Bothnian Sea and the Archipelago Sea. The absence of Fucus from many potential sites in the outer Archipelago Sea is likely due to its inability to recover from its disappearance from the area 30-40 years ago, highlighting the importance of past events in macroalgal occurrence. The methodology presented for mapping the potential distribution and the ecological value of reefs showed, that relatively high accuracy in mapping can be achieved by combining existing available data, and the maps produced serve as valuable background information for more detailed surveys. Taken together, the results of the theses contribute significantly to the knowledge on macroalgal communities of the northern Baltic Sea that can be directly applied in various management contexts.

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In photosynthesis, light energy is converted to chemical energy, which is consumed for carbon assimilation in the Calvin-Benson-Bassham (CBB) cycle. Intensive research has significantly advanced the understanding of how photosynthesis can survive in the ever-changing light conditions. However, precise details concerning the dynamic regulation of photosynthetic processes have remained elusive. The aim of my thesis was to specify some molecular mechanisms and interactions behind the regulation of photosynthetic reactions under environmental fluctuations. A genetic approach was employed, whereby Arabidopsis thaliana mutants deficient in specific photosynthetic protein components were subjected to adverse light conditions and assessed for functional deficiencies in the photosynthetic machinery. I examined three interconnected mechanisms: (i) auxiliary functions of PsbO1 and PsbO2 isoforms in the oxygen evolving complex of photosystem II (PSII), (ii) the regulatory function of PGR5 in photosynthetic electron transfer and (iii) the involvement of the Calcium Sensing Receptor CaS in photosynthetic performance. Analysis of photosynthetic properties in psbo1 and psbo2 mutants demonstrated that PSII is sensitive to light induced damage when PsbO2, rather than PsbO1, is present in the oxygen evolving complex. PsbO1 stabilizes PSII more efficiently compared to PsbO2 under light stress. However, PsbO2 shows a higher GTPase activity compared to PsbO1, and plants may partially compensate the lack of PsbO1 by increasing the rate of the PSII repair cycle. PGR5 proved vital in the protection of photosystem I (PSI) under fluctuating light conditions. Biophysical characterization of photosynthetic electron transfer reactions revealed that PGR5 regulates linear electron transfer by controlling proton motive force, which is crucial for the induction of the photoprotective non-photochemical quenching and the control of electron flow from PSII to PSI. I conclude that PGR5 controls linear electron transfer to protect PSI against light induced oxidative damage. I also found that PGR5 physically interacts with CaS, which is not needed for photoprotection of PSII or PSI in higher plants. Rather, transcript profiling and quantitative proteomic analysis suggested that CaS is functionally connected with the CBB cycle. This conclusion was supported by lowered amounts of specific calciumregulated CBB enzymes in cas mutant chloroplasts and by slow electron flow to PSI electron acceptors when leaves were reilluminated after an extended dark period. I propose that CaS is required for calcium regulation of the CBB cycle during periods of darkness. Moreover, CaS may also have a regulatory role in the activation of chloroplast ATPase. Through their diverse interactions, components of the photosynthetic machinery ensure optimization of light-driven electron transport and efficient basic production, while minimizing the harm caused by light induced photodamage.

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Pertinent domestic and international developments involving issues related to tensions affecting religious or belief communities have been increasingly occupying the international law agenda. Those who generate and, thus, shape international law jurisprudence are in the process of seeking some of the answers to these questions. Thus the need for reconceptualization of the right to freedom of religion or belief continues as demands to the right to freedom of religion or belief challenge the boundaries of religious freedom in national and international law. This thesis aims to contribute to the process of “re-conceptualization” by exploring the notion of the collective dimension of freedom of religion or belief with a view to advance the protection of the right to freedom of religion or belief. The case of Turkey provides a useful test case where both the domestic legislation can be assessed against international standards, while at the same time lessons can be drawn for the improvement of the standard of international review of the protection of the collective dimension of freedom of religion or belief. The right to freedom of religion or belief, as enshrined in international human rights documents, is unique in its formulation in that it provides protection for the enjoyment of the rights “in community with others”.1 It cannot be realized in isolation; it crosses categories of human rights with aspects that are individual, aspects that can be effectively realized only in an organized community of individuals and aspects that belong to the field of economic, social and cultural rights such as those related to religious or moral education. This study centers on two primary questions; first, what is the scope and nature of protection afforded to the collective dimension of freedom of religion or belief in international law, and, secondly, how does the protection of the collective dimension of freedom of religion or belief in Turkey compare and contrast to international standards? Section I explores and examines the notion of the collective dimension of freedom of religion or belief, and the scope of its protection in international law with particular reference to the right to acquire legal personality and autonomy religious/belief communities. In Section II, the case study on Turkey constitutes the applied part of the thesis; here, the protection of the collective dimension is assessed with a view to evaluate the compliance of Turkish legislation and practice with international norms as well as seeking to identify how the standard of international review of the collective dimension of freedom of religion or belief can be improved.

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Carbon dioxide is regarded, nowadays, as a primary anthropogenic greenhouse gas leading to global warming. Hence, chemical fixation of CO2 has attracted much attention as a possible way to manufacture useful chemicals. One of the most interesting approaches of CO2 transformations is the synthesis of organic carbonates. Since conventional production technologies of these compounds involve poisonous phosgene and carbon monoxide, there is a need to develop novel synthetic methods that would better match the principles of "Green Chemistry" towards protection of the environment and human health. Over the years, synthesis of dimethyl carbonate was under intensive investigation in the academia and industry. Therefore, this study was entirely directed towards equally important homologue of carbonic esters family namely diethyl carbonate (DEC). Novel synthesis method of DEC starting from ethanol and CO2 over heterogeneous catalysts based on ceria (CeO2) was studied in the batch reactor. However, the plausible drawback of the reaction is thermodynamic limitations. The calculated values revealed that the reaction is exothermic (ΔrHØ298K = ─ 16.6 J/ ) and does not occur spontaneously at rooms temperature (ΔrGØ 298K = 35.85 kJ/mol). Moreover, co-produced water easily shifts the reaction equilibrium towards reactants excluding achievement of high yields of the carbonate. Therefore, in-situ dehydration has been applied using butylene oxide as a chemical water trap. A 9-fold enhancement in the amount of DEC was observed upon introduction of butylene oxide to the reaction media in comparison to the synthetic method without any water removal. This result confirms that reaction equilibrium was shifted in favour of the desired product and thermodynamic boundaries of the reaction were suppressed by using butylene oxide as a water scavenger. In order to obtain insight into the reaction network, the kinetic experiments were performed over commercial cerium oxide. On the basis of the selectivity/conversion profile it could be concluded that the one-pot synthesis of diethyl carbonate from ethanol, CO2 and butylene oxide occurs via a consecutive route involving cyclic carbonate as an intermediate. Since commercial cerium oxide suffers from the deactivation problems already after first reaction cycle, in-house CeO2 was prepared applying room temperature precipitation technique. Variation of the synthesis parameters such as synthesis time, calcination temperature and pH of the reaction solution turned to have considerable influence on the physico-chemical and catalytic properties of CeO2. The increase of the synthesis time resulted in high specific surface area of cerium oxide and catalyst prepared within 50 h exhibited the highest amount of basic sites on its surface. Furthermore, synthesis under pH 11 yielded cerium oxide with the highest specific surface area, 139 m2/g, among all prepared catalysts. Moreover, CeO2─pH11 catalyst demonstrated the best catalytic activity and 2 mmol of DEC was produced at 180 oC and 9 MPa of the final reaction pressure. In addition, ceria-supported onto high specific surface area silicas MCM-41, SBA-15 and silica gel were synthesized and tested for the first time as catalysts in the synthesis of DEC. Deposition of cerium oxide on MCM-41 and SiO2 supports resulted in a substantial increase of the alkalinity of the carrier materials. Hexagonal SBA-15 modified with 20 wt % of ceria exhibited the second highest basicity in the series of supported catalysts. Evaluation of the catalytic activity of ceria-supported catalysts showed that reaction carried out over 20 wt % CeO2-SBA-15 generated the highest amount of DEC.

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Antiviral nucleosides are compounds that are used against viruses, such as human immunodeficiency virus (HIV) and hepatitis C virus (HCV). To act as therapeutic agent, the antiviral nucleoside needs to be phosphorylated to nucleotide in the body in three consecutive phosphorylation steps by cellular or viral enzymes. The first phosphorylation to the nucleoside monophosphate is often inefficient and leads to poor antiviral activity. The antiviral efficacy can be improved by applying a prodrug strategy and delivering the antiviral nucleoside directly as its monophosphate. In prodrug strategies of antiviral nucleotides, the negative charges on the phosphate moiety are temporarily masked with protecting groups. Once inside the cell, the protecting groups are removed by enzymatic or chemical processes. Many prodrug strategies apply biodegradable protecting groups, the removal of which is triggered by esterase enzymes. Several studies have, however, demonstrated that the removal rate of the second and subsequent esterase labile protecting groups significantly slows down after the first protecting group is removed due to the negative charge on the phosphodiester intermediate, which disturbs the catalytic site of the enzyme. In this thesis, esterase labile protecting group strategies where the issue of retardation could be avoided were studied. Prodrug candidates of antiviral nucleotides were synthesized and kinetic studies on the chemical and enzymatic stability were carried out. In the synthesized compounds, the second protecting group is cleaved from the monophosphate some other mechanism than esterase triggered activation or the structure of prodrug requires only one protecting group. In addition, esterase labile protecting group which is additionally thermally removable was studied. This protecting group was cleaved from oligomeric phosphodiesters both enzymatically and thermally and seems most attractive of the studied phosphate protecting groups. However, the rate of the thermal removal still is too slow to allow efficient protection of longer oligonucleotides and needs optimization. Key words: antiviral, nucleotide, prodrug, protecting group, biodegradable

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Gravitational phase separation is a common unit operation found in most large-scale chemical processes. The need for phase separation can arise e.g. from product purification or protection of downstream equipment. In gravitational phase separation, the phases separate without the application of an external force. This is achieved in vessels where the flow velocity is lowered substantially compared to pipe flow. If the velocity is low enough, the denser phase settles towards the bottom of the vessel while the lighter phase rises. To find optimal configurations for gravitational phase separator vessels, several different geometrical and internal design features were evaluated based on simulations using OpenFOAM computational fluid dynamics (CFD) software. The studied features included inlet distributors, vessel dimensions, demister configurations and gas phase outlet configurations. Simulations were conducted as single phase steady state calculations. For comparison, additional simulations were performed as dynamic single and two-phase calculations. The steady state single phase calculations provided indications on preferred configurations for most above mentioned features. The results of the dynamic simulations supported the utilization of the computationally faster steady state model as a practical engineering tool. However, the two-phase model provides more truthful results especially with flows where a single phase does not determine the flow characteristics.

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Today, renewable energy technologies and modern power electronics have made it feasible to implement low voltage direct current (LVDC) microgrids (MGs) ca-pable to island operation. Such LVDC networks are particularly useful in remote areas. However, there are still pending issues in island operated LVDC MGs like electrical safety and controlled operation, which should be addressed before wide-scale implementation. This thesis is focused on the overall protection of an island operated LVDC network concept, including protection against electrical shocks, mains equipment protection and protection of photovoltaic (PV) power sources and battery energy storage systems (BESSs). The topic is approached through ex-amination of the safety hazards and the appropriate methods to protect against them, comprising considerations for earthing system selection and realisation of the protection system.