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This clinical study focused on effects of childhood specific language impairment (SLI) on daily functioning in late life. SLI is a neurobiological disorder with genetic predisposition and manifests as poor language production or comprehension or both in a child with age-level non-verbal intelligence and no other known cause for deficient language development. The prevalence rate of around 7% puts it among the most prevalent developmental disorders in childhood. Negative long-term effects, such as problems in learning and behavior, are frequent. In follow-up studies the focus has seldom been on self-perception of daily functioning and participation, which are considered important in the International Classification of Functioning, Disability, and Health (ICF). To investigate the self-perceived aspects of everyday functioning in individuals with childhood receptive SLI compared with age- and gender-matched control populations, the 15D, 16D, and 17D health-related quality of life (HRQoL) questionnaires were applied. These generic questionnaires include 15, 16, and 17 dimensions, respectively, and give both a single index score and a profile with values on each dimension. Information on different life domains (rehabilitation, education, employment etc.) from each age-group was collected with separate questionnaires. The study groups comprised adults, adolescents (12-16 years), and pre-adolescents (8-11 years) who had received a diagnosis of receptive SLI and had been examined, usually before school age, at the Department of Phoniatrics of Helsinki University Central Hospital, where children with language deficits caused by various etiologies are examined and treated by a multidisciplinary team. The adult respondents included 33 subjects with a mean age of 34 years. Measured with 15D, the subjects perceived their HRQoL to be nearly as good as that of their controls, but on the dimensions of speech, usual activities, mental functioning, and distress they were significantly worse off. They significantly more often lived with their parents (19%) or were pensioned (26%) than the adult Finnish population on average. Adults with self-perceived problems in finding words and in remembering instructions, manifestations of persistent language impairment, showed inferior every day functioning to the rest of the study group. Of the adolescents and pre-adolescents, 48 and 51, respectively, responded. The majority in both groups had received special education or extra educational support at school. They all had attended speech therapy at some point; at the time of the study only one adolescent, but every third pre-adolescent still received speech therapy. The 16D score of the adolescent or the 17D score of the pre-adolescents did not differ from that of their controls. The 16D profiles differed on some dimensions; subjects were significantly worse off on the dimension of mental functioning, but better off on the dimension of vitality than controls. Of the 17D dimensions, the study group was significantly worse off on speech, whereas the control group reported significantly more problems in sleeping. Of the childhood performance measures investigated, low verbal intelligence quotient (VIQ), which is often considered to reflect receptive language impairment, was in adults subjects significantly associated with some of the self-perceived problems, such as problems in usual activities and mental functioning. The 15D, 16D, and 17D questionnaires served well in measuring self-perceived HRQoL. Such standardized measures with population values are especially important in confirming with the ICF guidelines. In the future these questionnaires could perhaps be used on a more individual level in follow-up of children in clinics, and even in special schools and classes, to detect those children at greatest risk of negative long-term effects and perhaps diminished well-being regarding daily functioning and participation.

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Rest tremor, rigidity, and slowness of movements-considered to be mainly due to markedly reduced levels of dopamine (DA) in the basal ganglia-are characteristic motor symptoms of Parkinson's disease (PD). Although there is yet no cure for this illness, several drugs can alleviate the motor symptoms. Among these symptomatic therapies, L-dopa is the most effective. As a precursor to DA, it is able to replace the loss of DA in the basal ganglia. In the long run L-dopa has, however, disadvantages. Motor response complications, such as shortening of the duration of drug effect ("wearing-off"), develop in many patients. In addition, extensive peripheral metabolism of L-dopa by aromatic amino acid decarboxylase and catechol-O-methyltransferase (COMT) results in its short half-life, low bioavailability, and reduced efficacy. Entacapone, a nitrocatechol-structured compound, is a highly selective, reversible, and orally active inhibitor of COMT. It increases the bioavailability of L-dopa by reducing its peripheral elimination rate. Entacapone extends the duration of clinical response to each L-dopa dose in PD patients with wearing-off fluctuations. COMT is important in the metabolism of catecholamines. Its inhibition could, therefore, theoretically lead to adverse cardiovascular reactions, especially in circumstances of enhanced sympathetic activity (physical exercise). PD patients may be particularly vulnerable to such effects due to high prevalence of cardiovascular autonomic dysfunction, and the common use of monoamine oxidase B inhibitor selegiline, another drug with effects on catecholamine metabolism. Both entacapone and selegiline enhance L-dopa's clinical effect. Their co-administration may therefore lead to pharmacodynamic interactions, either beneficial (improved L-dopa efficacy) or harmful (increased dyskinesia). We investigated the effects of repeated dosing (3-5 daily doses for 1-2 weeks) of entacapone 200 mg administered either with or without selegiline (10 mg once daily), on several safety and efficacy parameters in 39 L-dopa-treated patients with mild to moderate PD in three double-blind placebo-controlled, crossover studies. In the first two, the cardiovascular, clinical, and biochemical responses were assessed repeatedly for 6 hours after drug intake, first with L-dopa only (control), and then after a 2 weeks on study drugs (entacapone vs. entacapone plus selegiline in one; entacapone vs. selegiline vs. entacapone plus selegiline in the other). The third study included cardiovascular reflex and spiroergometric exercise testing, first after overnight L-dopa withdrawal (control), and then after 1 week on entacapone plus selegiline as adjuncts to L-dopa. Ambulatory ECG was recorded in two of the studies. Blood pressure, heart rate, ECG, cardiovascular autonomic function, cardiorespiratory exercise responses, and the resting/exercise levels of circulating catecholamines remained unaffected by entacapone, irrespective of selegiline. Entacapone significantly enhanced both L-dopa bioavailability and its clinical response, the latter being more pronounced with the co-administration of selegiline. Dyskinesias were also increased during simultaneous use of both entacapone and selegiline as L-dopa adjuncts. Entacapone had no effect on either work capacity or work efficiency. The drug was well tolerated, both with and without selegiline. Conclusions: the use of entacapone-either alone or combined with selegiline-seems to be hemodynamically safe in L-dopa-treated PD patients, also during maximal physical effort. This is in line with the safety experience from larger phase III studies. Entacapone had no effect on cardiovascular autonomic function. Concomitant administration of entacapone and selegiline may enhance L-dopa's clinical efficacy but may also lead to increased dyskinesia.

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Volatile organic compounds (VOCs) affect atmospheric chemistry and thereafter also participate in the climate change in many ways. The long-lived greenhouse gases and tropospheric ozone are the most important radiative forcing components warming the climate, while aerosols are the most important cooling component. VOCs can have warming effects on the climate: they participate in tropospheric ozone formation and compete for oxidants with the greenhouse gases thus, for example, lengthening the atmospheric lifetime of methane. Some VOCs, on the other hand, cool the atmosphere by taking part in the formation of aerosol particles. Some VOCs, in addition, have direct health effects, such as carcinogenic benzene. VOCs are emitted into the atmosphere in various processes. Primary emissions of VOC include biogenic emissions from vegetation, biomass burning and human activities. VOCs are also produced in secondary emissions from the reactions of other organic compounds. Globally, forests are the largest source of VOC entering the atmosphere. This thesis focuses on the measurement results of emissions and concentrations of VOCs in one of the largest vegetation zones in the world, the boreal zone. An automated sampling system was designed and built for continuous VOC concentration and emission measurements with a proton transfer reaction - mass spectrometer (PTR-MS). The system measured one hour at a time in three-hourly cycles: 1) ambient volume mixing-ratios of VOCs in the Scots-pine-dominated boreal forest, 2) VOC fluxes above the canopy, and 3) VOC emissions from Scots pine shoots. In addition to the online PTR-MS measurements, we determined the composition and seasonality of the VOC emissions from a Siberian larch with adsorbent samples and GC-MS analysis. The VOC emissions from Siberian larch were reported for the fist time in the literature. The VOC emissions were 90% monoterpenes (mainly sabinene) and the rest sesquiterpenes (mainly a-farnesene). The normalized monoterpene emission potentials were highest in late summer, rising again in late autumn. The normalized sesquiterpene emission potentials were also highest in late summer, but decreased towards the autumn. The emissions of mono- and sesquiterpenes from the deciduous Siberian larch, as well as the emissions of monoterpenes measured from the evergreen Scots pine, were well described by the temperature-dependent algorithm. In the Scots-pine-dominated forest, canopy-scale emissions of monoterpenes and oxygenated VOCs (OVOCs) were of the same magnitude. Methanol and acetone were the most abundant OVOCs emitted from the forest and also in the ambient air. Annually, methanol and mixing ratios were of the order of 1 ppbv. The monoterpene and sum of isoprene 2-methyl-3-buten-2-ol (MBO) volume mixing-ratios were an order of magnitude lower. The majority of the monoterpene and methanol emissions from the Scots-pinedominated forest were explained by emissions from Scots pine shoots. The VOCs were divided into three classes based on the dynamics of the summer-time concentrations: 1) reactive compounds with local biological, anthropogenic or chemical sources (methanol, acetone, butanol and hexanal), 2) compounds whose emissions are only temperaturedependent (monoterpenes), 3) long-lived compounds (benzene, acetaldehyde). Biogenic VOC (methanol, acetone, isoprene MBO and monoterpene) volume mixing-ratios had clear diurnal patterns during summer. The ambient mixing ratios of other VOCs did not show this behaviour. During winter we did not observe systematical diurnal cycles for any of the VOCs. Different sources, removal processes and turbulent mixing explained the dynamics of the measured mixing-ratios qualitatively. However, quantitative understanding will require longterm emission measurements of the OVOCs and the use of comprehensive chemistry models. Keywords: Hydrocarbons, VOC, fluxes, volume mixing-ratio, boreal forest

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There is a relative absence of sociological and cultural research on how people deal with the death of a family member in the contemporary western societies. Research on this topic has been dominated by the experts of psychology, psychiatry and therapy, who mention the social context only in passing, if at all. This gives an impression that the white westerners bereavement experience is a purely psychological phenomenon, an inner journey, which follows a natural, universal path. Yet, as Tony Walter (1999) states, ignoring the influence of culture not only impoverishes the understanding of those work with bereaved people, but it also impoverishes sociology and cultural studies by excluding from their domain a key social phenomenon. This study explores the cultural dimension of grief through narratives told by fifteen of recently bereaved Finnish women. Focussing on one sex only, the study rests on the assumption of the gendered nature of bereavement experience. However, the aim of the study is not to pinpoint the gender differences in grief and mourning, but to shed light on women s ways of dealing with the loss of a loved one in a social context. Furthermore, the study focuses on a certain kind of loss: the death of an elderly parent. Due to the growth in the life expectancy rate, this has presumably become the most typical type of bereavement in contemporary, ageing societies. Most of population will face the death of a parent as they reach the middle years of the life course. The data of this study is gathered with interviews, in which the interviewees were invited to tell a narrative of their bereavement. Narrative constitutes a central concept in this study. It refers to a particular form of talk, which is organised around consequential events. But there are also other, deeper layers that have been added to this concept. Several scholars see narratives as the most important way in which we make sense of experience. Personal narratives provide rich material for mapping the interconnections between individual and culture. As a form of thought, narrative marries singular circumstances with shared expectations and understandings that are learned through participation in a specific culture (Garro & Mattingly 2000). This study attempts to capture the cultural dimension of narrative with the concept of script , which originates in cognitive science (Schank & Abelson 1977) and has recently been adopted to narratology (Herman 2002). Script refers to a data structure that informs how events usually unfold in certain situations. Scripts are used in interpreting events and representing them verbally to others. They are based on dominant forms of knowledge that vary according to time and place. The questions that were posed in this study are the following. What kind of experiences bereaved daughters narrate? What kind of cultural scripts they employ as they attempt to make sense of these experiences? How these scripts are used in their narratives? It became apparent that for the most of the daughters interviewed in this study the single most important part of the bereavement narrative was to form an account of how and why the parent died. They produced lengthy and detailed descriptions of the last stage of a parent s life in contrast with the rest of the interview. These stories took their start from a turn in the parent s physical condition, from which the dying process could in retrospect be seen to have started, and which often took place several years before the death. In addition, daughters also talked about their grief reactions and how they have adjusted to a life without the deceased parent. The ways in which the last stage of life was told reflect not only the characteristic features of late modernity but also processes of marginalisation and exclusion. Revivalist script and medical script, identified by Clive Seale as the dominant, competing models for dying well in the late modern societies, were not widely utilised in the narratives. They could only be applied in situations in which the parent had died from cancer and at somewhat younger age than the average. Death that took place in deep old age was told in a different way. The lack of positive models for narrating this kind of death was acknowledged in the study. This can be seen as a symptom of the societal devaluing of the deaths of older people and it affects also daughters accounts of their grief. Several daughters told about situations in which their loss, although subjectively experienced, was nonetheless denied by other people.

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Suurin ongelma syöpätautien lääkehoidossa on sen aiheuttamat toksiset sivuvaikutukset. Tyypillisesti vain noin 1 % elimistöön annostellusta lääkeaineesta saavuttaa hoitoa tarvitsevat syöpäsolut, loppuosa lääkeaineesta jää vahingoittamaan elimistön terveitä soluja. Toksiset sivuvaikutukset rajoittavat lääkehoidon annoksen nostamista elimistössä riittävälle pitoisuudelle, mikä johtaa usein sairauden ennenaikaiseen pahenemiseen ja mahdollisen lääkeaineresistenssin kehittymiseen. Liposomien välittämä lääkeaineen kohdentaminen voidaan jakaa kahteen eri menetelmään: passiiviseen ja aktiiviseen kohdentamiseen. Liposomien passiivisen kohdentamisen tarkoituksena on lisätä sytotoksisen lääkeaineen paikallistumista pelkästään kasvainkudokseen. Passiivinen kohdentaminen perustuu liposomien kulkeutumiseen verenkierron mukana, jolloin liposomit kerääntyvät epänormaalisti muodostuneeseen kasvainkudokseen. Liposomien aktiivisella kohdentamisella pyritään parantamaan passiivisesti kohdentuvien liposomien terapeuttista tehokkuutta kohdentamalla lääkeaineen vaikutus pelkästään syöpäsoluihin. Aktiivisessa kohdennuksessa liposomin pintaan kiinnitetään ligandi, joka spesifisesti tunnistaa kohdesolun. Tämän pro gradu -tutkielman kirjallisen osion tarkoituksena oli tutustua syöpäkudokseen kohdennettujen liposomien ominaisuuksiin tehokkaan soluunoton ja sytotoksisuuden saavuttamiseksi. Kokeellisessa osiossa tutkittiin kohdennettujen liposomien soluunottoa ja sytotoksista vaikutusta ihmisen munasarjasta eristetyillä adenokarsinoomasoluilla (SKOV-3). Liposomit kohdennettiin setuksimabi (C225, Erbitux®) vasta-aineella, jonka on todettu olevan tietyissä syöpätyypeissä (mm. keuhko- ja kolorektaalisyövissä, pään ja kaulan syövissä sekä rinta-, munuais-, eturauhas-, haima- ja munasarjasyövissä) yli-ilmentyneen epidermaalisen kasvutekijäreseptoriperheen HER1-proteiinin (ErbB-1, EGFR, epidermal growth factor receptor) spesifinen ja selektiivinen inhibiittori. Afrikan viherapinan munuaisista lähtöisin olevaa CV-1 solulinjaa käytettiin kontrollina kuvaamaan elimistön normaaleja soluja. Kohdennettujen liposomien soluunottoa tutkittiin soluunottokokeilla, joissa käytettiin kontrollina kohdentamattomia pegyloituja liposomeja. Setuksimabi-vasta-aineen spesifinen sitoutuminen EGF-reseptoriin todettiin kilpailutuskokeilla. Doksorubisiinia sisältävien immunoliposomien sytotoksisuutta selvitettiin Alamar Blue™ -elävyystestillä. Lisäksi immunoliposomien säilyvyyttä seurattiin mittaamalla liposomien keskimääräinen halkaisija noin kahden viikon välein. Setuksimabi-vasta-aineella kohdennettujen liposomien soluunotto oli huomattavasti suurentunut SKOV-3 syöpäsoluissa ja doksorubisiinia sisältävät kohdennetut liposomit aiheuttivat voimakkaamman sytotoksisen vaikutuksen kuin kohdentamattomat liposomit. Kohdennettujen doksorubisiiniliposomien sytotoksisuus tuli kuitenkin esille viiveellä, mikä viittaa lääkeaineen hitaaseen vapautumiseen liposomista. Suurentunutta soluunottoa ja sytotoksista vaikutusta ei havaittu CV-1 solulinjassa. Kohdennettujen liposomien sovellusmahdollisuudet lääketieteessä ja syövän hoidossa ovat merkittävät. Tällä hetkellä liposomien kliininen käyttö rajoittuu passiivisesti kohdennettuihin liposomeihin (Doxil® (Am.),Caelyx® (Eur.)). Lupaavista solukokeista huolimatta kohdennettujen liposomien terapeuttinen käyttö tulevaisuudessa näyttää haasteelliselta.

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Monocarboxylate transporters (MCTs) transport lactate and protons across cell membranes. During intense exercise, lactate and protons accumulate in the exercising muscle and are transported to the plasma. In the horse, MCTs are responsible for the majority of lactate and proton removal from exercising muscle, and are therefore also the main mechanism to hinder the decline in pH in muscle cells. Two isoforms, MCT1 and MCT4, which need an ancillary protein CD147, are expressed in equine muscle. In the horse, as in other species, MCT1 is predominantly expressed in oxidative fibres, where its likely role is to transport lactate into the fibre to be used as a fuel at rest and during light work, and to remove lactate during intensive exercise when anaerobic energy production is needed. The expression of CD147 follows the fibre type distribution of MCT1. These proteins were detected in both the cytoplasm and sarcolemma of muscle cells in the horse breeds studied: Standardbred and Coldblood trotters. In humans, training increases the expression of both MCT1 and MCT4. In this study, the proportion of oxidative fibres in the muscle of Norwegian-Swedish Coldblood trotters increased with training. Simultaneously, the expression of MCT1 and CD147, measured immunohistochemically, seemed to increase more in the cytoplasm of oxidative fibres than in the fast fibre type IIB. Horse MCT4 antibody failed to work in immunohistochemistry. In the future, a quantitative method should be introduced to examine the effect of training on muscle MCT expression in the horse. Lactate can be taken up from plasma by red blood cells (RBCs). In horses, two isoforms, MCT1 and MCT2, and the ancillary protein CD147 are expressed in RBC membranes. The horse is the only species studied in which RBCs have been found to express MCT2, and the physiological role of this protein in RBCs is unknown. The majority of horses express all three proteins, but 10-20% of horses express little or no MCT1 or CD147. This leads to large interindividual variation in the capacity to transport lactate into RBCs. Here, the expression level of MCT1 and CD147 was bimodally distributed in three studied horse breeds: Finnhorse, Standardbred and Thoroughbred. The level of MCT2 expression was distributed unimodally. The expression level of lactate transporters could not be linked to performance markers in Thoroughbred racehorses. In the future, better performance indexes should be developed to better enable the assessment of whether the level of MCT expression affects athletic performance. In human subjects, several mutations in MCT1 have been shown to cause decreased lactate transport activity in muscle and signs of myopathy. In the horse, two amino acid sequence variations, one of which was novel, were detected in MCT1 (V432I and K457Q). The mutations found in horses were in different areas compared to mutations found in humans. One mutation (M125V) was detected in CD147. The mutations found could not be linked with exercise-induced myopathy. MCT4 cDNA was sequenced for the first time in the horse, but no mutations could be detected in this protein.

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Volatile organic compounds (VOCs) are emitted into the atmosphere from natural and anthropogenic sources, vegetation being the dominant source on a global scale. Some of these reactive compounds are deemed major contributors or inhibitors to aerosol particle formation and growth, thus making VOC measurements essential for current climate change research. This thesis discusses ecosystem scale VOC fluxes measured above a boreal Scots pine dominated forest in southern Finland. The flux measurements were performed using the micrometeorological disjunct eddy covariance (DEC) method combined with proton transfer reaction mass spectrometry (PTR-MS), which is an online technique for measuring VOC concentrations. The measurement, calibration, and calculation procedures developed in this work proved to be well suited to long-term VOC concentration and flux measurements with PTR-MS. A new averaging approach based on running averaged covariance functions improved the determination of the lag time between wind and concentration measurements, which is a common challenge in DEC when measuring fluxes near the detection limit. The ecosystem scale emissions of methanol, acetaldehyde, and acetone were substantial. These three oxygenated VOCs made up about half of the total emissions, with the rest comprised of monoterpenes. Contrary to the traditional assumption that monoterpene emissions from Scots pine originate mainly as evaporation from specialized storage pools, the DEC measurements indicated a significant contribution from de novo biosynthesis to the ecosystem scale monoterpene emissions. This thesis offers practical guidelines for long-term DEC measurements with PTR-MS. In particular, the new averaging approach to the lag time determination seems useful in the automation of DEC flux calculations. Seasonal variation in the monoterpene biosynthesis and the detailed structure of a revised hybrid algorithm, describing both de novo and pool emissions, should be determined in further studies to improve biological realism in the modelling of monoterpene emissions from Scots pine forests. The increasing number of DEC measurements of oxygenated VOCs will probably enable better estimates of the role of these compounds in plant physiology and tropospheric chemistry. Keywords: disjunct eddy covariance, lag time determination, long-term flux measurements, proton transfer reaction mass spectrometry, Scots pine forests, volatile organic compounds

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Despite its bad reputation in the mass media, cholesterol is an indispensable constituent of cellular membranes and vertebrate life. It is, however, also potentially lethal as it may accumulate in the arterial intima causing atherosclerosis or elsewhere in the body due to inherited conditions. Studying cholesterol in cells, and research on how the cell biology of cholesterol affects on system level is essential for a better understanding of the disease states associated with cholesterol and for the development of new therapies for these conditions. On its way to the cell, exogenous cholesterol traverses through endosomes, transport vesicles involved in internalizing material to cells, and needs to be transported out of this compartment. This endosomal pool of cholesterol is important for understanding both the common disorders of metabolism and the more rare hereditary disorders of cholesterol metabolism. The study of cholesterol in cells has been hampered by the lack of bright fluorescent sterol analogs that would resemble cholesterol enough to be used in cellular studies. In the first study of my thesis, we present a new sterol analog, Boron-Dipyrromethene (BODIPY)-cholesterol for visualizing sterols in living cells and organism. This fluorescent cholesterol derivative is shown to behave similarly to cholesterol both by atomic scale computer simulations and biochemical experiments. We characterize its localization inside different types of living cells and show that it can be used to study sterol trafficking in living organisms. Two sterol binding proteins associated with the endosomal membrane; the Niemann-Pick type C disease protein 1 (NPC1) and the Oxysterol Binding Protein Related Protein 1 (ORP1) are the subjects of the rest of this study. Sensing cholesterol on endosomes, transporting lipids away from this compartment and the effects these lipids play on cellular metabolism are considered. In the second study we characterize how the NPC1 protein affects lipid metabolism. We show that this cholesterol binding protein affects synthesis of triglycerides and that genetic polymorphisms or a genetic defect in the NPC1 gene affect triglyceride on the whole body level. These effects take place via regulation of carbon fluxes to different lipid classes in cells. In the third part we characterize the effects of another endosomal sterol binding protein, ORP1L on the function and motility of endosomes. Specifically we elucidate how a mutation in the ability of ORP1L to bind sterols affects its behavior in cells, and how a change in ORP1L levels in cells affects the localization, degradative capacity and motility of endosomes. In addition we show that ORP1L manipulations affect cholesterol balance also in macrophages, a cell type important for the development of atherosclerosis.

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As the virtual world grows more complex, finding a standard way for storing data becomes increasingly important. Ideally, each data item would be brought into the computer system only once. References for data items need to be cryptographically verifiable, so the data can maintain its identity while being passed around. This way there will be only one copy of the users family photo album, while the user can use multiple tools to show or manipulate the album. Copies of users data could be stored on some of his family members computer, some of his computers, but also at some online services which he uses. When all actors operate over one replicated copy of the data, the system automatically avoids a single point of failure. Thus the data will not disappear with one computer breaking, or one service provider going out of business. One shared copy also makes it possible to delete a piece of data from all systems at once, on users request. In our research we tried to find a model that would make data manageable to users, and make it possible to have the same data stored at various locations. We studied three systems, Persona, Freenet, and GNUnet, that suggest different models for protecting user data. The main application areas of the systems studied include securing online social networks, providing anonymous web, and preventing censorship in file-sharing. Each of the systems studied store user data on machines belonging to third parties. The systems differ in measures they take to protect their users from data loss, forged information, censorship, and being monitored. All of the systems use cryptography to secure names used for the content, and to protect the data from outsiders. Based on the gained knowledge, we built a prototype platform called Peerscape, which stores user data in a synchronized, protected database. Data items themselves are protected with cryptography against forgery, but not encrypted as the focus has been disseminating the data directly among family and friends instead of letting third parties store the information. We turned the synchronizing database into peer-to-peer web by revealing its contents through an integrated http server. The REST-like http API supports development of applications in javascript. To evaluate the platform’s suitability for application development we wrote some simple applications, including a public chat room, bittorrent site, and a flower growing game. During our early tests we came to the conclusion that using the platform for simple applications works well. As web standards develop further, writing applications for the platform should become easier. Any system this complex will have its problems, and we are not expecting our platform to replace the existing web, but are fairly impressed with the results and consider our work important from the perspective of managing user data.

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As the virtual world grows more complex, finding a standard way for storing data becomes increasingly important. Ideally, each data item would be brought into the computer system only once. References for data items need to be cryptographically verifiable, so the data can maintain its identity while being passed around. This way there will be only one copy of the users family photo album, while the user can use multiple tools to show or manipulate the album. Copies of users data could be stored on some of his family members computer, some of his computers, but also at some online services which he uses. When all actors operate over one replicated copy of the data, the system automatically avoids a single point of failure. Thus the data will not disappear with one computer breaking, or one service provider going out of business. One shared copy also makes it possible to delete a piece of data from all systems at once, on users request. In our research we tried to find a model that would make data manageable to users, and make it possible to have the same data stored at various locations. We studied three systems, Persona, Freenet, and GNUnet, that suggest different models for protecting user data. The main application areas of the systems studied include securing online social networks, providing anonymous web, and preventing censorship in file-sharing. Each of the systems studied store user data on machines belonging to third parties. The systems differ in measures they take to protect their users from data loss, forged information, censorship, and being monitored. All of the systems use cryptography to secure names used for the content, and to protect the data from outsiders. Based on the gained knowledge, we built a prototype platform called Peerscape, which stores user data in a synchronized, protected database. Data items themselves are protected with cryptography against forgery, but not encrypted as the focus has been disseminating the data directly among family and friends instead of letting third parties store the information. We turned the synchronizing database into peer-to-peer web by revealing its contents through an integrated http server. The REST-like http API supports development of applications in javascript. To evaluate the platform s suitability for application development we wrote some simple applications, including a public chat room, bittorrent site, and a flower growing game. During our early tests we came to the conclusion that using the platform for simple applications works well. As web standards develop further, writing applications for the platform should become easier. Any system this complex will have its problems, and we are not expecting our platform to replace the existing web, but are fairly impressed with the results and consider our work important from the perspective of managing user data.

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This book is on cross-border competence management in Russia and China. Corporations are facing a number of problems and challenges in their international operations, to which there typically are no simple solutions. For instance, they need to understand and respond to cultural and institutional diversity and ascertain that their foreign units are integrated with the rest of the corporation. Throughout this report we will discuss a range of challenges confronting firms as they seek to develop their capabilities to operate internationally. Some of the challenges are clearly case specific, and although this book aims to offer research-based advice to practicing managers there is a potential danger in applying lessons from other companies to the own firm. Our hope is that our analyses of the challenges facing Finnish corporations in China and Russia reported together with extensive quotes from our interviews and insights from other recent studies will help readers draw their own conclusions as to how to deal with issues related to competence management across borders. With this book we also aspire to contribute to the academic literature by providing new insights into cross-border competence management in general and the operations of Finnish corporations in Russia and China in particular.

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Purpose - The purpose of the paper is to explore the practice of marketing in micro firms. Which are the challenges micro firms encounter and how do they handle them? Methodology - The research methodology is based on the theory-in-use approach (Zaltman, Heffring & LeMasters 1982) in order to inductively explore the practice of marketing in micro firms. The empirical findings rest on ten case studies, where data has been generated through repeated interactions with each case. Findings - The empirical findings show that micro firms handle their marketing challenges in a distinctive manner, by creatively using available resources and network relations. Marketing in micro firms is largely about a long-term, gradual development of a position on the market. This process we label germinal marketing. Two key dimensions of germinal marketing were identified: “earning your position” and “being your brand”. Research limitations and implications - The findings rest on an explorative study consisting of ten cases and the general applicability of the results need to be validated by further studies. These cases are however sufficient to illuminate the need for further research into the area. Value of the paper - The value of the paper is twofold. First, it expands the theory-in-use approach, and presents a research method for successful inductive empirical studies of small firm phenomena. Secondly, the paper widens our understanding of the marketing reality and practice of micro firms, identifying new dimensions of marketing and revealing the strategic implications of ordinary business activities.

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Congenital long QT syndrome (LQTS) is a familial disorder characterized by ventricular repolarization that makes carriers vulnerable to malignant ventricular tachycardia and sudden cardiac death. The three main subtypes (LQT1, LQT2 and LQT3) constitute 95% of cases. The disorder is characterized by a prolonged QT interval in electrocardiograms (ECG), but a considerable portion are silent carriers presenting normal (QTc < 440 ms) or borderline (QTc < 470 ms) QT interval. Genetic testing is available only for 60-70% of patients. A number of pharmaceutical compounds also affect ventricular repolarization, causing a clinically similar disorder called acquired long QT syndrome. LQTS carriers - who already have impaired ventricular repolarization - are especially vulnerable. In this thesis, asymptomatic genotyped LQTS mutation carriers with non-diagnostic resting ECG were studied. The body surface potential mapping (BSPM) system was utilized for ECG recording, and signals were analyzed with an automated analysis program. QT interval length, and the end part of the T wave, the Tpe interval, was studied during exercise stress testing and an epinephrine bolus test. In the latter, T wave morphology was also analyzed. The effect of cetirizine was studied in LQTS carriers and also with supra- therapeutic dose in healthy volunteers. At rest, LQTS mutation carriers had a slightly longer heart rate adjusted QTc interval than healthy subjects (427 ± 31 ms and 379 ± 26 ms; p<0.001), but significant overlapping existed. LQT2 mutation carriers had a conspicuously long Tpe-interval (113 ± 24 ms; compared to 79 ± 11 ms in LQT1, 81 ± 17 ms in LQT3 and 78 ± 10 ms in controls; p<0.001). In exercise stress tests, LQT1 mutation carriers exhibit a long QT interval at high heart rates and during recovery, whereas LQT2 mutation carriers have a long Tpe interval at the beginning of exercise and at the end of recovery at low heart rates. LQT3 mutation carriers exhibit prominent shortening of both QT and Tpe intervals during exercise. A small epinephrine bolus revealed disturbed repolarization, especially in LQT2 mutation carriers, who developed prolonged Tpe intervals. A higher epinephrine bolus caused abnormal T waves with a different T wave profile in LQTS mutation carriers compared to healthy controls. These effects were seen in LQT3 as well, a group that may easily escape other provocative tests. In the cetirizine test, the QT and Tpe intervals were not prolonged in LQTS mutation carriers or in healthy controls. Subtype-specific findings in exercise test and epinephrine bolus test help to diagnose silent LQTS mutation carriers and to guide subtype-specific treatments. The Tpe interval, which signifies the repolarization process, seems to be a sensitive marker of disturbed repolarization along with the QT interval, which signifies the end of repolarization. This method may be used in studying compounds that are suspected to affect repolarization. Cetirizine did not adversely alter ventricular repolarization and would not be pro-arrhythmic in common LQT1 and LQT2 subtypes when used at its recommended doses.

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Monocarboxylate transporters (MCTs), especially the isoforms MCT1 - MCT4, cotransport lactate and protons across the cell membranes. They are thus essential for pH regulation and homeostasis in glycolytic cells such as red blood cells (RBCs), and skeletal muscle cells during intense exercise. In 70% of the Standardbred horses the lactate transport activity (TA) in RBCs is high and transport is mediated mainly by MCTs. In the rest 30% of the Standardbreds MCT mediated transport route is not active and the TA is low. MCTs need an ancillary protein for their proper localization and functioning in the plasma membrane. The ancillary protein for MCT1 and MCT4 is a member of immunoglobulin superfamily, CD147. Here we determined the expression of MCT isoforms and CD147 in equine RBCs and gluteal muscle. We sequenced the cDNA of horse MCT1 and CD147 to achieve horse-specific antibodies and to reveal sequence variations that may affect the TA of RBCs. The amount of MCT1 and CD147 mRNA in muscle were also studied. ---- In all, 73 horses representing different breeds were used. Blood samples were drawn from the jugular vein and muscle samples were taken either from gluteal muscle using biopsy needle or during castration from expendable cremaster muscle. The TA of RBCs was studied using radiolabeled lactate and the amount of MCT isoforms and CD147 in the plasma membranes using Western blotting. The level of mRNA in muscle cells was determined using qPCR. Isoforms MCT1 and MCT2 were found in the RBCs and isoforms MCT1 and MCT4 in the muscle cells of horses. The TA of RBCs was dependent on the expression of CD147 and MCT1 in the plasma membrane. Sequence variations were found in the cDNA of both MCT1 and CD147, but they did not explain the inactivity of MCT1 mediated transport route. The single nucleotide polymorphism (SNP) Met125Val in CD147 that existed parallel with an SNP in 3´-untranslated region explained, however, attenuation in CD147 expression in Standardbreds. A single mutation Ile51Val also decreased the expression of CD147 in one Warmblood. The MCT1 and CD147 mRNA concentrations in the gluteal muscle were higher in horses with higher MCT1 and CD147 expression in RBCs and lower in horses with minor expression of CD147 and MCT1. This suggests that the bimodal distribution of TA is due to differences in transcriptional regulation that is functioning in parallel in MCT1 and CD147 gene.

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Ewing sarcoma is an aggressive and poorly differentiated malignancy of bone and soft tissue. It primarily affects children, adolescents, and young adults, with a slight male predominance. It is characterized by a translocation between chromosomes 11 and 22 resulting in the EWSR1-FLI1fusion transcription factor. The aim of this study is to identify putative Ewing sarcoma target genes through an integrative analysis of three microarray data sets. Array comparative genomic hybridization is used to measure changes in DNA copy number, and analyzed to detect common chromosomal aberrations. mRNA and miRNA microarrays are used to measure expression of protein-coding and miRNA genes, and these results integrated with the copy number data. Chromosomal aberrations typically contain also bystanders in addition to the driving tumor suppressor and oncogenes, and integration with expression helps to identify the true targets. Correlation between expression of miRNAs and their predicted target mRNAs is also evaluated to assess the results of post-transcriptional miRNA regulation on mRNA levels. The highest frequencies of copy number gains were identified in chromosome 8, 1q, and X. Losses were most frequent in 9p21.3, which also showed an enrichment of copy number breakpoints relative to the rest of the genome. Copy number losses in 9p21.3 were found have a statistically significant effect on the expression of MTAP, but not on CDKN2A, which is a known tumor-suppressor in the same locus. MTAP was also down-regulated in the Ewing sarcoma cell lines compared to mesenchymal stem cells. Genes exhibiting elevated expression in association with copy number gains and up-regulation compared to the reference samples included DCAF7, ENO2, MTCP1, andSTK40. Differentially expressed miRNAs were detected by comparing Ewing sarcoma cell lines against mesenchymal stem cells. 21 up-regulated and 32 down-regulated miRNAs were identified, includingmiR-145, which has been previously linked to Ewing sarcoma. The EWSR1-FLI1 fusion gene represses miR-145, which in turn targets FLI1 forming a mutually repressive feedback loop. In addition higher expression linked to copy number gains and compared to mesenchymal stem cells, STK40 was also found to be a target of four different miRNAs that were all down-regulated in Ewing sarcoma cell lines compared to the reference samples. SLCO5A1 was identified as the only up-regulated gene within a frequently gained region in chromosome 8. This region was gained in over 90 % of the cell lines, and also with a higher frequency than the neighboring regions. In addition, SLCO5A1 was found to be a target of three miRNAs that were down-regulated compared to the mesenchymal stem cells.