49 resultados para High-through put screening


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The aim of this study is to investigate the consumer search behavior in high involvement purchases. The results of this research provide the descriptive analysis of the information search phase which is a part of the decision-making process. The study focuses on customer’s choice of the information sources, motivation behind it and different factors that influence the search behavior. Particular attention is paid to the purchase categorization and the differences in information search between products and services. The qualitative research method is chosen for this study. The data is gathered through ten theme interviews. Each participant of the interview describes his/her own search behavior in a product and a service case. The results indicate that consumer search behavior vary according to the purchase categorization, demographic, individual and situational factors. Moreover, the above-mentioned factors influence the purpose and position of the information search phase in a five-step decision making model.

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This study examines the place of The Church of Jesus Christ of Latter-day Saints (commonly known as the Mormon church) in the Russian Grand Duchy of Finland between the years 1840 and 1900. Attention is put on both the internal workings of the movement and the reactions of society. Theoretical insight is gained through the concepts of social construction and religious economies. Mormon image formation in Finland began by 1840 through newspaper reports on activities abroad and through essays on the faith’s history and doctrine. Mormons are mentioned almost 3,500 times in Finnish newspapers between 1840 and 1900, and at least twelve unique book titles sold in the country were explicitly devoted to discussing Mormonism. Most of the publicity was derived from foreign sources. Discourse analysis of this textual corpus shows a hegemonic discourse that combined themes such as fraud, deception, and theocracy in explaining the Mormon movement. Accompanied by plural marriage, these themes contributed to the construction of a strongly negative image of Mormonism already before the first missionaries arrived in 1875. In a society with a stringently regulated religious economy, this image contributed to a high level of resistance by civil authorities and Lutheran clergy. Twenty-five Mormon missionaries worked in Finland between 1875 and 1900, with a concentrated effort taking place between 1875 and 1889. At least 78 persons converted, mostly in the coastal areas among the Swedish-speaking minority population. Nine percent emigrated to Utah, 36% were excommunicated, others fell into oblivion, while still others clung to their new faith. The work was led from Sweden, with no stable church organization emerging among the isolated pockets of converts. Mormonism’s presence was thus characterized by private or small-group religiosity rather than a vibrant movement. The lack of religious community, conversation, and secondary socialization eventually caused the nineteenth-century manifestation of Finnish Mormonism to die out. Only one group of converts was perpetuated past World War II, after which large-scale proselytizing began.

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High-throughput screening of cellular effects of RNA interference (RNAi) libraries is now being increasingly applied to explore the role of genes in specific cell biological processes and disease states. However, the technology is still limited to specialty laboratories, due to the requirements for robotic infrastructure, access to expensive reagent libraries, expertise in high-throughput screening assay development, standardization, data analysis and applications. In the future, alternative screening platforms will be required to expand functional large-scale experiments to include more RNAi constructs, allow combinatorial loss-of-function analyses (e.g. genegene or gene-drug interaction), gain-of-function screens, multi-parametric phenotypic readouts or comparative analysis of many different cell types. Such comprehensive perturbation of gene networks in cells will require a major increase in the flexibility of the screening platforms, throughput and reduction of costs. As an alternative for the conventional multi-well based high-throughput screening -platforms, here the development of a novel cell spot microarray method for production of high density siRNA reverse transfection arrays is described. The cell spot microarray platform is distinguished from the majority of other transfection cell microarray techniques by the spatially confined array layout that allow highly parallel screening of large-scale RNAi reagent libraries with assays otherwise difficult or not applicable to high-throughput screening. This study depicts the development of the cell spot microarray method along with biological application examples of high-content immunofluorescence and phenotype based cancer cell biological analyses focusing on the regulation of prostate cancer cell growth, maintenance of genomic integrity in breast cancer cells, and functional analysis of integrin protein-protein interactions in situ.

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The drug discovery process is facing new challenges in the evaluation process of the lead compounds as the number of new compounds synthesized is increasing. The potentiality of test compounds is most frequently assayed through the binding of the test compound to the target molecule or receptor, or measuring functional secondary effects caused by the test compound in the target model cells, tissues or organism. Modern homogeneous high-throughput-screening (HTS) assays for purified estrogen receptors (ER) utilize various luminescence based detection methods. Fluorescence polarization (FP) is a standard method for ER ligand binding assay. It was used to demonstrate the performance of two-photon excitation of fluorescence (TPFE) vs. the conventional one-photon excitation method. As result, the TPFE method showed improved dynamics and was found to be comparable with the conventional method. It also held potential for efficient miniaturization. Other luminescence based ER assays utilize energy transfer from a long-lifetime luminescent label e.g. lanthanide chelates (Eu, Tb) to a prompt luminescent label, the signal being read in a time-resolved mode. As an alternative to this method, a new single-label (Eu) time-resolved detection method was developed, based on the quenching of the label by a soluble quencher molecule when displaced from the receptor to the solution phase by an unlabeled competing ligand. The new method was paralleled with the standard FP method. It was shown to yield comparable results with the FP method and found to hold a significantly higher signal-tobackground ratio than FP. Cell-based functional assays for determining the extent of cell surface adhesion molecule (CAM) expression combined with microscopy analysis of the target molecules would provide improved information content, compared to an expression level assay alone. In this work, immune response was simulated by exposing endothelial cells to cytokine stimulation and the resulting increase in the level of adhesion molecule expression was analyzed on fixed cells by means of immunocytochemistry utilizing specific long-lifetime luminophore labeled antibodies against chosen adhesion molecules. Results showed that the method was capable of use in amulti-parametric assay for protein expression levels of several CAMs simultaneously, combined with analysis of the cellular localization of the chosen adhesion molecules through time-resolved luminescence microscopy inspection.

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Breast cancer that has metastasized to bone is currently an incurable disease, causing significant morbidity and mortality. The aim of this thesis work was to elucidate molecular mechanisms of bone metastasis and thereby gain insights into novel therapeutic approaches. First, we found that L‐serine biosynthesis genes, phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1) and phosphoserine phosphatase (PSPH), were up‐regulated in highly bone metastatic MDA‐MB‐231(SA) cells as compared with the parental breast cancer cell line. Knockdown of serine biosynthesis inhibited proliferation of MDA‐MB‐231(SA) cells, and L‐serine was essential for the formation of bone resorbing osteoclasts. Clinical data demonstrated that high expression of PHGDH and PSAT1 was associated with decreased relapse‐free and overall survival and with features typical of poor outcome in breast cancer. Second, RNA interference screening pointed out heparan sulfate 6‐O‐sulfotransferase 2 (HS6ST2) as a critical gene for transforming growth factor β (TGF‐β)‐induced interleukin 11 (IL‐11) production in MDA‐MB‐231(SA) cells. Exogenous heparan sulfate glycosaminoglycans heparin and K5‐NSOS also inhibited TGF‐β‐induced IL‐11 production in MDA‐MB‐231(SA) cells. Furthermore, K5‐NSOS decreased osteolytic lesion area and tumor burden in bone in mice. Third, we discovered that the microRNAs miR‐204, ‐211 and ‐379 inhibited IL‐11 expression in MDA‐MB‐231(SA) cells through direct targeting of the IL‐11 mRNA. MiR‐379 also inhibited Smad‐mediated signaling. Gene expression profiling of miR‐204 and ‐379 transfected cells indicated that these microRNAs down‐regulate several bone metastasis‐relevant genes, including prostaglandin‐endoperoxide synthase 2 (PTGS2). Taken together, this study identified three potential treatment strategies for bone metastatic breast cancer: inhibition of serine biosynthesis, heparan sulfate glycosaminoglycans and restoration of miR‐204/‐211/‐379.

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Väitöskirjan tavoitteena on ollut rakentaa kokonaiskuva aiheesta Jugoslavialaisen sotataidollisen ajattelun kehittyminen toisen maailmansodan jälkeen. Tutkimuksessa ei ole rajoituttu ainoastaan kuvailemaan sotataidollisen ajattelun kehittyminen, vaan on pyritty selvittämään kehittymiseen vaikuttaneet tekijät ja vastaamaan kysymykseen, miksi näin on tapahtunut? Aiemmat länsimaiset tutkimukset ovat tarkastelleet jugoslavialaista sotataitoa tai maanpuolustusta vain jostain tietystä rajallisesta näkökulmasta, kuten esimerkiksi Jugoslavian kansanarmeijaa, asevoimien vaikutusta maan poliittiseen elämään tai sotilaallista doktriinia koskien. Sotataidon kehittymiseen vaikuttavat tekijät huomioivaa kokonaisesitystä ole tehty. Myös jugoslavialainen sotataidollinen ajattelu on jäänyt pääosin pimentoon. Jugoslavialainen maan sotataitoon kohdistunut tutkimus on ollut laajaa ja monipuolista, mutta sen käytettävyyteen osittain vaikuttaa marxilais-leniniläinen materialistis-dialektinen, historialliseen materialismiin perustuva tutkimusmenetelmä. Väitöskirjan päätutkimusaineiston ovat muodostaneet alkuperäislähteet, ensisijaisesti jugoslavialaiset ohjesäännöt, käsikirjat, oppaat ja oppikirjat. Muu lähteistö on koostunut lähinnä arkistoasiakirjoista ja muusta kirjallisuudesta. Tutkimusmenetelmä on ollut historiatieteellinen käsittäen muun muassa ulkoisen ja sisäisen lähdekritiikin harjoittamisen, tietojen varmistamisen mahdollisimman useasta toisistaan riippumattomasta lähteestä sekä pyrkimyksen rekonstruoida ristiriidaton kokonaiskuva tutkimuskohteesta. Eri lähteistä ja lähderyhmistä saatuja tietoja on vertailtu, analysoitu sekä yhdistetty kriittisesti. Lähteiden käytettävyyden, lähdearvon ja luotettavuuden arviointi ovat olleet merkittävässä roolissa, näistä kaikista tärkeimpänä luotettavuuden arviointi. Sisäisen ja ulkoisen lähdekritiikin keinoin on pyritty luomaan oma ristiriidaton tulkinta kokonaisuudesta, jugoslavialaisen sotataidollisen ajattelun kehittymisestä toisen maailmansodan jälkeen. Tutkimuksessa on pitäydytty niin pitkälle kuin mahdollista jugoslavialaisen sotataidon alkuperäisessä terminologiassa. Jugoslavialaisia termejä ei ole muokattu vastaamaan paremmin esimerkiksi tällä hetkellä länsimaisessa sotataidossa käytettyjä käsitteitä. Väitöskirjan rakenne on temaattinen. Läpi koko tutkittavan ajanjakson jugoslavialaisen sotataidollisen ajattelun kehittymisessä on tunnistettavissa samat määräävät tekijät: historialliset taustatekijät, sotilaallinen uhka, sotilaallinen doktriini, lakiperusteet, kommunistiliiton ohjaus ja asevoimien sekä yhteiskunnan valmiuden kehittyminen. Jugoslaviassa puhuttiin aseelliseen kamppailuun vaikuttavista sodankäynnin faktoreista, joita olivat yhteiskunnalliset tekijät, materiaalis-tekniset tekijät ja sotilaalliset tekijät. Kaikista tärkeimpänä tekijänä pidettiin kuitenkin ihmistä itseään, vaikka ihmisen merkitys välillä tuntuikin hukkuvan ”moraalis-poliittiset tekijät”-sanahirviön alle. Tutkimuskysymyksiin on vastattu sotataitoon vaikuttaneiden edellä mainittujen tekijöiden kautta. Kuhunkin muutostekijään liittyvä kehitys on kuvattu kronologisena esityksenä. Kansan vapautussodassa vuosina 1941–1945 perustettujen partisaaniyksiköiden muodostamisessa sekä niiden toimintamenetelmissä on havaittavissa runsaasti yhtymäkohtia 1700- ja 1800-luvun hajdukkijoukkojen sekä 1800-luvun lopun ja 1900-luvun alun četnikkijoukkojen vastaaviin periaatteisiin. Samankaltaisuuksia ilmenee 1950-luvulta alkaen alueellisen puolustuksen joukkojen ja partisaaniyksiköiden toimintamenetelmien yhteydessä väliaikaisesti menetetyllä alueella toimittaessa. Kansan tukeen, karismaattisiin johtajiin ja yllätyselementtiin perustuva sissitoiminta on perinteistä eteläslaavilaista sotataitoa. Sodanjälkeinen jugoslavialainen sotataito oli jatkumoa eteläslaavien vuosisatoja vanhalle sotataidolliselle perinteelle, vaikka sitä ei julkisesti Jugoslaviassa muutamia poikkeuksia lukuun ottamatta myönnettykään. Jugoslavian sotilaallinen doktriini oli luotu kaikista suunnista kohdistuvia hyökkäyksiä vastaan, mutta sotilaallisen uhkan painotukset vaihtelivat usein, jopa vain muutaman vuoden välein. Tämä ei johtunut päättämättömyydestä eikä pelkästään koetun uhkan suunnan vaihtumisesta. Painottamalla sisäisen ja ulkoisen uhkan jatkuvuutta sekä uhkan suunnan vaihtelua pyrittiin pitämään maanpuolustuspiirit valppaina ja kansalaiset aktiivisina. Tällä tavalla myös perusteltiin maanpuolustuksen korkeita kustannuksia ja ennen kaikkea pyrittiin lisäämään maan sisäistä veljeyttä ja yhtenäisyyttä. On ilmeistä, että sekä lännestä että idästä kohdistui Jugoslavian suuntaan suurta poliittista ja sotilaallista intressiä kylmän sodan vuosina 1945–1990, mutta suoran sotilaallisen uhkan aukoton todistaminen olisi kuitenkin hankalaa. Oleellista onkin jugoslavialaisten oma käsitys maataan vastaan kohdistuneesta sotilaallisesta uhkasta. Sisäisen uhkan vaikutus alkoi kasvaa 1970-luvun alkupuolelta lähtien ja se johti lopulta 1980-luvulla alueellisen puolustuksen joukkojen esikuntien lakkauttamiseen ja taisteluvälineiden hajavarastointijärjestelmän purkamiseen. Yhteiskunnallisista tekijöistä merkittävimpinä sotataitoon ja sotataidolliseen ajatteluun vaikuttaneina osina olivat lait ja Jugoslavian kommunistiliitto. Perustuslakiin ja lakiin kansallisesta puolustuksesta sekä kommunistiliiton päätöslauselmiin sisällytetyt vaatimukset sotataidon kehittymiselle kuitenkin vain toistivat sotilaallisessa doktriinissa määritettyjä suuntaviivoja sekä määräyksiä. Maanpuolustukseen liittyneiden määräysten ja ohjeiden hyväksymiselle laillisen järjestyksen mukaisesti annettiin kuitenkin erittäin suuri arvo. Niiden toimeenpanon leviäminen maanlaajuisesti varmistettiin puolueen päätöksillä velvoittamalla muun muassa kommunistiliiton paikallisorganisaatiot, puoluesolut asevoimien sisällä sekä kaikki liittovaltion hallintotasot tekemään kaikkensa yleisen kansanpuolustuksen ja sitä ilmentävän sotataidon toteutumisen eteen. Materiaalis-teknisen tekijän kokonaisuus sisälsi aseet ja varusteet sekä niihin liittyviä muita seikkoja, kuten yhteiskunnan teollisuuden kehittymisen asteen sekä kyvyn suojautua vihollisen taisteluvälineitä vastaan ja luoda vihollisen aseita vastaan tehokkaampi vasta-ase. Siihen luettiin myös yksilöiden, taktisten ja yhdistettyjen taktisten yksiköiden sekä koko kansan koulutus aseiden ja varusteiden tarkoituksenmukaiseen käyttöön. Vaikka jugoslavialainen aseteollisuus kehittyi tutkimusperiodin aikana voimakkaasti, joutui maa taloudellisten resurssiensa rajallisuuden ja mahdollisen vihollishyökkäyksen ylivoimaisuuden havaittuaan toteamaan, että maanpuolustuksen ongelmia ei voida ratkaista materiaalin ja tekniikan määrällä tai laadulla. Ratkaisun oli löydyttävä sotilaallisista tekijöistä ja varsinkin sotataidosta. Sotilaalliset tekijät ja prosessit olivat jugoslavialaisen sotataidon ja sotataidollisen ajattelun kehittymisen kannalta tärkein muutostekijä. Sotilaallisten tekijöiden ytimen muodosti sotataito, joka Jugoslaviassa koostui teoriasta ja käytännöstä. Tämä jako koski sotataidon kolmea tasoa: strategiaa, operatiikkaa ja taktiikkaa. Sotataitoon kuuluvina osina pidettiin muun muassa taisteluvalmiutta, liikekannallepanovalmiutta, yhteiskunnallis-poliittisten yhteisöjen aseetonta vastarintaa, aseellisen kamppailun operatiivista ja taktista tasoa, materiaalista ja teknistä varustamista, sotatalouden valmistelujen organisointia sekä yhteiskunnallisia palveluja poikkeusoloissa. Osa näistä kuului edellä mainittuihin yhteiskunnallisiin tai materiaalis-teknisiin tekijöihin. Jugoslavialainen sotataito onkin nähtävä matriisinomaisena kokonaisuutena, jossa sotataidon kolmeen toiminnalliseen tasoon, strategiaan, operatiikkaan ja taktiikkaan vaikuttivat historialliset taustatekijät, sotilaallinen uhka, yhteiskunnalliset tekijät ja materiaalis-tekniset tekijät. Jugoslavialaisen sotataidon kokonaisuuteen kuului myös se, että mainitut muutostekijät vaikuttivat vielä toisiinsa. Lopputuloksena näin kokonaisvaltaisesta näkemyksestä sotataitoon ja sotataidolliseen ajatteluun Jugoslavia kykeni luomaan poikkeuksellisen tehokkaana pidetyn puolustusratkaisun, jossa koko yhteiskunnan kaikki resurssit pystyttiin suuntaamaan hyökkäyksen torjumiseen ja maahan tunkeutuneiden pois ajamiseen. Aiempi tutkimus on nähnyt jugoslavialaisen sotataidon kehittymisen keskeisimpänä vaikuttimena ja murroskohtana Varsovan liiton joukkojen toimeenpaneman Tšekkoslovakian miehityksen ja siitä seuranneen koetun uhkan merkittävän voimistumisen. Yleisen kansanpuolustuksen doktriiniin liittyvä taustatutkimus, teorianmuodostus ja doktriinin käyttöönotto tapahtuivat kuitenkin jo 1950-luvulla. Tšekkoslovakian miehitys toimi vain muutoksen toimeenpanoa vauhdittavana tekijänä. Jugoslavialaiset korostivat, että jugoslavialaisessa yhteiskunnassa keskeisessä asemassa ollut yhteisjohtoisuuden periaate ulottui myös maanpuolustukseen ja sotataitoon. Tutkimusaineistoon perehtyminen kuitenkin osoitti, että yleisen kansanpuolustuksen kokonaisuutta kuvaavat oppikirjat, laeissa asetetut määräykset ja Jugoslavian kommunistiliiton julkaisemat vaatimukset eivät olleet jalkautuneet sotataidon teoriaan tai käytäntöön operatiivisella tai taktisella tasolla. Strategisella tasolla yhteisjohtoisuus esiintyi näkyvämmin vain sotilaallisen konseptin ja strategian yhteydessä. Sotilaallisen doktriinin osalta yhteisjohtoisuus ilmeni lähinnä kahdessa asiassa. Alueellisen puolustuksen yksiköiden varustamisvelvoite oli asetettu siviilihallinnon eri tasojen vastuulle. Alueellisen puolustuksen esikunnat ja komentajat olivat vastuussa yleisen kansanpuolustuksen ja yhteiskunnallisen itsesuojelun komiteoille. Siviilihallinnon organisaatioiden kyky varustaa alueellisen puolustuksen yksiköt osoittautui kuitenkin heikoksi. Alueellisen puolustuksen esikunnatkin toimivat upseereiden johtamina sotilaallisina johtoportaina, ja yleisen kansanpuolustuksen ja yhteiskunnallisen itsesuojelun komiteoiden toiminta komentajien ja esikuntien suuntaan rajoittui vain nimelliseen ohjaukseen. Yhteisjohtoisuus osoittautuikin tutkimuksen kuluessa piirteeksi, joka julkisesta retoriikasta huolimatta ei toteutunut jugoslavialaisessa sotataidon praktiikassa. Jugoslavialaisen sotataidollisen ajattelun kehittymisen kaari käynnistyi partisaanisodasta ja päätyi alueelliseen puolustusjärjestelmään. Kansakunta ja sen useat eri kansallisuudet onnistuivat luomaan tieteelliseen ja tutkittuun tietoon perustuvan välineen, sotataidon teorian ja käytännön, joka suojeli maata yli puolen vuosisadan ajan. Yleinen kansanpuolustus sekä jugoslavialainen sotataito ovat toisiensa synonyymejä, seurauksia ja synnyttäjiä. Puolustusratkaisu lähti omista kansallisista lähtökohdista, siihen sulautettiin valikoiden ja jalostettuna hyviksi sekä menestyksekkäiksi koettuja ulkomaisia elementtejä sekä vaikutteita. Sitä perusteltiin monipuolisilla poliittisilla, ideologisilla, teoreettisilla, historiallisilla sekä nykyaikaisilla sotataidollisilla argumenteilla, mutta kaikesta tästä huolimatta sen ydin oli omintakeinen jugoslavialainen sotataidollinen ajattelu.

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Cells of epithelial origin, e.g. from breast and prostate cancers, effectively differentiate into complex multicellular structures when cultured in three-dimensions (3D) instead of conventional two-dimensional (2D) adherent surfaces. The spectrum of different organotypic morphologies is highly dependent on the culture environment that can be either non-adherent or scaffold-based. When embedded in physiological extracellular matrices (ECMs), such as laminin-rich basement membrane extracts, normal epithelial cells differentiate into acinar spheroids reminiscent of glandular ductal structures. Transformed cancer cells, in contrast, typically fail to undergo acinar morphogenic patterns, forming poorly differentiated or invasive multicellular structures. The 3D cancer spheroids are widely accepted to better recapitulate various tumorigenic processes and drug responses. So far, however, 3D models have been employed predominantly in the Academia, whereas the pharmaceutical industry has yet to adopt a more widely and routine use. This is mainly due to poor characterisation of cell models, lack of standardised workflows and high throughput cell culture platforms, and the availability of proper readout and quantification tools. In this thesis, a complete workflow has been established entailing well-characterised 3D cell culture models for prostate cancer, a standardised 3D cell culture routine based on high-throughput-ready platform, automated image acquisition with concomitant morphometric image analysis, and data visualisation, in order to enable large-scale high-content screens. Our integrated suite of software and statistical analysis tools were optimised and validated using a comprehensive panel of prostate cancer cell lines and 3D models. The tools quantify multiple key cancer-relevant morphological features, ranging from cancer cell invasion through multicellular differentiation to growth, and detect dynamic changes both in morphology and function, such as cell death and apoptosis, in response to experimental perturbations including RNA interference and small molecule inhibitors. Our panel of cell lines included many non-transformed and most currently available classic prostate cancer cell lines, which were characterised for their morphogenetic properties in 3D laminin-rich ECM. The phenotypes and gene expression profiles were evaluated concerning their relevance for pre-clinical drug discovery, disease modelling and basic research. In addition, a spontaneous model for invasive transformation was discovered, displaying a highdegree of epithelial plasticity. This plasticity is mediated by an abundant bioactive serum lipid, lysophosphatidic acid (LPA), and its receptor LPAR1. The invasive transformation was caused by abrupt cytoskeletal rearrangement through impaired G protein alpha 12/13 and RhoA/ROCK, and mediated by upregulated adenylyl cyclase/cyclic AMP (cAMP)/protein kinase A, and Rac/ PAK pathways. The spontaneous invasion model tangibly exemplifies the biological relevance of organotypic cell culture models. Overall, this thesis work underlines the power of novel morphometric screening tools in drug discovery.

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This doctoral thesis presents a study on the development of a liquid-cooled frame salient pole permanent-magnet-exited traction machine for a four-wheel-driven electric car. The emphasis of the thesis is put on a radial flux machine design in order to achieve a light-weight machine structure for traction applications. The design features combine electromagnetic and thermal design methods, because traction machine operation does not have a strict operating point. Arbitrary load cycles and the flexible supply require special attention in the design process. It is shown that accurate modelling of the machine magnetic state is essential for high-performance operation. The saturation effect related to the cross-saturation has to be taken carefully into account in order to achieve the desired operation. Two prototype machines have been designed and built for testing: one totally enclosed machine with a special magnet module pole arrangement and another through-ventilated machine with a more traditional embedded magnet structure. Both structures are built with magnetically salient structures in order to increase the torque production capability with the reluctance torque component. Both machine structures show potential for traction usage. However, the traditional embedded magnet design turns out to be mechanically the more secure one of these two machine options.

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In many industrial applications, such as the printing and coatings industry, wetting of porous materials by liquids includes not only imbibition and permeation into the bulk but also surface spreading and evaporation. By understanding these phenomena, valuable information can be obtained for improved process control, runnability and printability, in which liquid penetration and subsequent drying play important quality and economic roles. Knowledge of the position of the wetting front and the distribution/degree of pore filling within the structure is crucial in describing the transport phenomena involved. Although exemplifying paper as a porous medium in this work, the generalisation to dynamic liquid transfer onto a surface, including permeation and imbibition into porous media, is of importance to many industrial and naturally occurring environmental processes. This thesis explains the phenomena in the field of heatset web offset printing but the content and the analyses are applicable in many other printing methods and also other technologies where water/moisture monitoring is crucial in order to have a stable process and achieve high quality end products. The use of near-infrared technology to study the water and moisture response of porous pigmented structures is presented. The use of sensitive surface chemical and structural analysis, as well as the internal structure investigation of a porous structure, to inspect liquid wetting and distribution, complements the information obtained by spectroscopic techniques. Strong emphasis has been put on the scale of measurement, to filter irrelevant information and to understand the relationship between interactions involved. The near-infrared spectroscopic technique, presented here, samples directly the changes in signal absorbance and its variation in the process at multiple locations in a print production line. The in-line non-contact measurements are facilitated by using several diffuse reflectance probes, giving the absolute water/moisture content from a defined position in the dynamic process in real-time. The nearinfrared measurement data illustrate the changes in moisture content as the paper is passing through the printing nips and dryer, respectively, and the analysis of the mechanisms involved highlight the roles of the contacting surfaces and the relative liquid carrier properties of both non-image and printed image areas. The thesis includes laboratory studies on wetting of porous media in the form of coated paper and compressed pigment tablets by mono-, dual-, and multi-component liquids, and paper water/moisture content analysis in both offline and online conditions, thus also enabling direct sampling of temporal water/moisture profiles from multiple locations. One main focus in this thesis was to establish a measurement system which is able to monitor rapid changes in moisture content of paper. The study suggests that near-infrared diffuse reflectance spectroscopy can be used as a moisture sensitive system and to provide accurate online qualitative indicators, but, also, when accurately calibrated, can provide quantification of water/moisture levels, its distribution and dynamic liquid transfer. Due to the high sensitivity, samples can be measured with excellent reproducibility and good signal to noise ratio. Another focus of this thesis was on the evolution of the moisture content, i.e. changes in moisture content referred to (re)wetting, and liquid distribution during printing of coated paper. The study confirmed different wetting phases together with the factors affecting each phase both for a single droplet and a liquid film applied on a porous substrate. For a single droplet, initial capillary driven imbibition is followed by equilibrium pore filling and liquid retreat by evaporation. In the case of a liquid film applied on paper, the controlling factors defining the transportation were concluded to be the applied liquid volume in relation to surface roughness, capillarity and permeability of the coating giving the liquid uptake capacity. The printing trials confirmed moisture gradients in the printed sheet depending on process parameters such as speed, fountain solution dosage and drying conditions as well as the printed layout itself. Uneven moisture distribution in the printed sheet was identified to be one of the sources for waving appearance and the magnitude of waving was influenced by the drying conditions.

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This study investigated the surface hardening of steels via experimental tests using a multi-kilowatt fiber laser as the laser source. The influence of laser power and laser power density on the hardening effect was investigated. The microhardness analysis of various laser hardened steels was done. A thermodynamic model was developed to evaluate the thermal process of the surface treatment of a wide thin steel plate with a Gaussian laser beam. The effect of laser linear oscillation hardening (LLOS) of steel was examined. An as-rolled ferritic-pearlitic steel and a tempered martensitic steel with 0.37 wt% C content were hardened under various laser power levels and laser power densities. The optimum power density that produced the maximum hardness was found to be dependent on the laser power. The effect of laser power density on the produced hardness was revealed. The surface hardness, hardened depth and required laser power density were compared between the samples. Fiber laser was briefly compared with high power diode laser in hardening medium-carbon steel. Microhardness (HV0.01) test was done on seven different laser hardened steels, including rolled steel, quenched and tempered steel, soft annealed alloyed steel and conventionally through-hardened steel consisting of different carbon and alloy contents. The surface hardness and hardened depth were compared among the samples. The effect of grain size on surface hardness of ferritic-pearlitic steel and pearlitic-cementite steel was evaluated. In-grain indentation was done to measure the hardness of pearlitic and cementite structures. The macrohardness of the base material was found to be related to the microhardness of the softer phase structure. The measured microhardness values were compared with the conventional macrohardness (HV5) results. A thermodynamic model was developed to calculate the temperature cycle, Ac1 and Ac3 boundaries, homogenization time and cooling rate. The equations were numerically solved with an error of less than 10-8. The temperature distributions for various thicknesses were compared under different laser traverse speed. The lag of the was verified by experiments done on six different steels. The calculated thermal cycle and hardened depth were compared with measured data. Correction coefficients were applied to the model for AISI 4340 steel. AISI 4340 steel was hardened by laser linear oscillation hardening (LLOS). Equations were derived to calculate the overlapped width of adjacent tracks and the number of overlapped scans in the center of the scanned track. The effect of oscillation frequency on the hardened depth was investigated by microscopic evaluation and hardness measurement. The homogeneity of hardness and hardened depth with different processing parameters were investigated. The hardness profiles were compared with the results obtained with conventional single-track hardening. LLOS was proved to be well suitable for surface hardening in a relatively large rectangular area with considerable depth of hardening. Compared with conventional single-track scanning, LLOS produced notably smaller hardened depths while at 40 and 100 Hz LLOS resulted in higher hardness within a depth of about 0.6 mm.

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Whereas external social media has been studied, hyped and integrated into companies´ strategies, an insignificant concentration has been put on internal social solutions, which companies provide increasingly to their personnel. An enterprise focusing solely on the benefits of external social media might end up underestimating the true potential embedded in social business. The purpose of this thesis was to examine how social collaboration can be depicted as a structuration process in an Enterprise 2.0 environment. Furthermore, this thesis sought to reveal the benefits, challenges and possibilities of social business. This thesis focused on researching Enterprise 2.0 at the workplace. The studied Enterprise 2.0 solution was IBM Connections. The qualitative research methodology was an extensive case study. Three companies took part into this thesis and all in all 12 employees were interviewed. Additionally, seven IBM Social Business Experts were interviewed in order to receive a better understanding of the phenomenon. Three research questions were designed to fulfill the purpose of this thesis. The research questions were: 1. How are the dimensions of social capital structured through collaboration? 2. How does agency form in Enterprise 2.0? 3. How does social collaboration emerge as a result of the interplay between agency and dimensions of social capital in an Enterprise 2.0 environment and creates outcomes such as trust, identification and knowledge? The main research findings indicate that social collaboration increases trust, identification and knowledge by giving employees more capabilities to do their work. Consequently, social collaboration increases company performance by making individuals and groups more effective. The support of top management is crucial in making Enterprise 2.0 successful, because it is more a cultural than a technological change. Power agency, the lack of top management support and old established work ways such as email and databases work as barriers to social collaboration.

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High strength steel (HSS) has been in use in workshops since the 1980s. At that time, the significance of the term HSS differed from the modern conception as the maximum yield strength of HSSs has increased nearly every year. There are three different ways to make HSS. The first and oldest method is QT (quenched and tempered) followed by the TMCP (thermomechanical controlled process) and DQ (direct quenching) methods. This thesis consists of two parts, the first of which part introduces the research topic and discusses welded HSS structures by characterizing the most important variables. In the second part of the thesis, the usability of welded HSS structures is examined through a set of laboratory tests. The results of this study explain the differences in the usability of the welded HSSs made by the three different methods. The results additionally indicate that usage of different HSSs in the welded structures presumes that manufacturers know what kind of HSS they are welding. As manufacturers use greater strength HSSs in welded structures, the demands for welding rise as well. Therefore, during the manufacturing process, factors such as heat input, cooling time, weld quality, and more must be under careful observation.

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Biotechnology has been recognized as the key strategic technology for industrial growth. The industry is heavily dependent on basic research. Finland continues to rank in the top 10 of Europe's most innovative countries in terms of tax-policy, education system, infrastructure and the number of patents issued. Regardless of the excellent statistical results, the output of this innovativeness is below acceptable. Research on the issues hindering the output creation has already been done and the identifiable weaknesses in the Finland's National Innovation system are the non-existent growth of entrepreneurship and the missing internationalization. Finland is proven to have all the enablers of the innovation policy tools, but is lacking the incentives and rewards to push the enablers, such as knowledge and human capital, forward. Science Parks are the biggest operator in research institutes in the Finnish Science and Technology system. They exist with the purpose of speeding up the commercialization process of biotechnology innovations which usually include technological uncertainty, technical inexperience, business inexperience and high technology cost. Innovation management only internally is a rather historic approach, current trend drives towards open innovation model with strong triple helix linkages. The evident problems in the innovation management within the biotechnology industry are examined through a case study approach including analysis of the semi-structured interviews which included biotechnology and business expertise from Turku School of Economics. The results from the interviews supported the theoretical implications as well as conclusions derived from the pilot survey, which focused on the companies inside Turku Science Park network. One major issue that the Finland's National innovation system is struggling with is the fact that it is technology driven, not business pulled. Another problem is the university evaluation scale which focuses more on number of graduates and short-term factors, when it should put more emphasis on the cooperation success in the long-term, such as the triple helix connections with interaction and knowledge distribution. The results of this thesis indicated that there is indeed requirement for some structural changes in the Finland's National innovation system and innovation policy in order to generate successful biotechnology companies and innovation output. There is lack of joint output and scales of success, lack of people with experience, lack of language skills, lack of business knowledge and lack of growth companies.

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Permanent magnet generators (PMG) represent the cutting edge technology in modern wind mills. The efficiency remains high (over 90%) at partial loads. To improve the machine efficiency even further, every aspect of machine losses has to be analyzed. Additional losses are often given as a certain percentage without providing any detailed information about the actual calculation process; meanwhile, there are many design-dependent losses that have an effect on the total amount of additional losses and that have to be taken into consideration. Additional losses are most often eddy current losses in different parts of the machine. These losses are usually difficult to calculate in the design process. In this doctoral thesis, some additional losses are identified and modeled. Further, suggestions on how to minimize the losses are given. Iron losses can differ significantly between the measured no-load values and the loss values under load. In addition, with embedded magnet rotors, the quadrature-axis armature reaction adds losses to the stator iron by manipulating the harmonic content of the flux. It was, therefore, re-evaluated that in salient pole machines, to minimize the losses and the loss difference between the no-load and load operation, the flux density has to be kept below 1.5 T in the stator yoke, which is the traditional guideline for machine designers. Eddy current losses may occur in the end-winding area and in the support structure of the machine, that is, in the finger plate and the clamping ring. With construction steel, these losses account for 0.08% of the input power of the machine. These losses can be reduced almost to zero by using nonmagnetic stainless steel. In addition, the machine housing may be subjected to eddy current losses if the flux density exceeds 1.5 T in the stator yoke. Winding losses can rise rapidly when high frequencies and 10–15 mm high conductors are used. In general, minimizing the winding losses is simple. For example, it can be done by dividing the conductor into transposed subconductors. However, this comes with the expense of an increase in the DC resistance. In the doctoral thesis, a new method is presented to minimize the winding losses by applying a litz wire with noninsulated strands. The construction is the same as in a normal litz wire but the insulation between the subconductors has been left out. The idea is that the connection is kept weak to prevent harmful eddy currents from flowing. Moreover, the analytical solution for calculating the AC resistance factor of the litz-wire is supplemented by including an end-winding resistance in the analytical solution. A simple measurement device is developed to measure the AC resistance in the windings. In the case of a litz-wire with originally noninsulated strands, vacuum pressure impregnation (VPI) is used to insulate the subconductors. In one of the two cases studied, the VPI affected the AC resistance factor, but in the other case, it did not have any effect. However, more research is needed to determine the effect of the VPI on litz-wire with noninsulated strands. An empirical model is developed to calculate the AC resistance factor of a single-layer formwound winding. The model includes the end-winding length and the number of strands and turns. The end winding includes the circulating current (eddy currents that are traveling through the whole winding between parallel strands) and the main current. The end-winding length also affects the total AC resistance factor.

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The Travel and Tourism field is undergoing changes due to the rapid development of information technology and digital services. Online travel has profoundly changed the way travel and tourism organizations interact with their customers. Mobile technology such as mobile services for pocket devices (e.g. mobile phones) has the potential to take this development even further. Nevertheless, many issues have been highlighted since the early days of mobile services development (e.g. the lack of relevance, ease of use of many services). However, the wide adoption of smartphones and the mobile Internet in many countries as well as the formation of so-called ecosystems between vendors of mobile technology indicate that many of these issues have been overcome. Also when looking at the numbers of downloaded applications related to travel in application stores like Google Play, it seems obvious that mobile travel and tourism services are adopted and used by many individuals. However, as business is expected to start booming in the mobile era, many issues have a tendency to be overlooked. Travelers are generally on the go and thus services that work effectively in mobile settings (e.g. during a trip) are essential. Hence, the individuals’ perceived drivers and barriers to use mobile travel and tourism services in on-site or during trip settings seem particularly valuable to understand; thus this is one primary aim of the thesis. We are, however, also interested in understanding different types of mobile travel service users. Individuals may indeed be very different in their propensity to adopt and use technology based innovations (services). Research is also switching more from investigating issues of mobile service development to understanding individuals’ usage patterns of mobile services. But designing new mobile services may be a complex matter from a service provider perspective. Hence, our secondary aim is to provide insights into drivers and barriers of mobile travel and tourism service development from a holistic business model perspective. To accomplish the research objectives seven different studies have been conducted over a time period from 2002 – 2013. The studies are founded on and contribute to theories within diffusion of innovations, technology acceptance, value creation, user experience and business model development. Several different research methods are utilized: surveys, field and laboratory experiments and action research. The findings suggest that a successful mobile travel and tourism service is a service which supports one or several mobile motives (needs) of individuals such as spontaneous needs, time-critical arrangements, efficiency ambitions, mobility related needs (location features) and entertainment needs. The service could be customized to support travelers’ style of traveling (e.g. organized travel or independent travel) and should be easy to use, especially easy to take into use (access, install and learn) during a trip, without causing security concerns and/or financial risks for the user. In fact, the findings suggest that the most prominent barrier to the use of mobile travel and tourism services during a trip is an individual’s perceived financial cost (entry costs and usage costs). It should, however, be noted that regulations are put in place in the EU regarding data roaming prices between European countries and national telecom operators are starting to see ‘international data subscriptions’ as a sales advantage (e.g. Finnish Sonera provides a data subscription in the Baltic and Nordic region at the same price as in Finland), which will enhance the adoption of mobile travel and tourism services also in international contexts. In order to speed up the adoption rate travel service providers could consider e.g. more local initiatives of free Wi-Fi networks, development of services that can be used, at least to some extent, in an offline mode (do not require costly network access during a trip) and cooperation with telecom operators (e.g. lower usage costs for travelers who use specific mobile services or travel with specific vendors). Furthermore, based on a developed framework for user experience of mobile trip arrangements, the results show that a well-designed mobile site and/or native application, which preferably supports integration with other mobile services, is a must for true mobile presence. In fact, travel service providers who want to build a relationship with their customers need to consider a downloadable native application, but in order to be found through the mobile channel and make contact with potential new customers, a mobile website should be available. Moreover, we have made a first attempt with cluster analysis to identify user categories of mobile services in a travel and tourism context. The following four categories were identified: info-seekers, checkers, bookers and all-rounders. For example “all-rounders”, represented primarily by individuals who use their pocket device for almost any of the investigated mobile travel services, constituted primarily of 23 to 50 year old males with high travel frequency and great online experience. The results also indicate that travel service providers will increasingly become multi-channel providers. To manage multiple online channels, closely integrated and hybrid online platforms for different devices, supporting all steps in a traveler process should be considered. It could be useful for travel service providers to focus more on developing browser-based mobile services (HTML5-solutions) than native applications that work only with specific operating systems and for specific devices. Based on an action research study and utilizing a holistic business model framework called STOF we found that HTML5 as an emerging platform, at least for now, has some limitations regarding the development of the user experience and monetizing the application. In fact, a native application store (e.g. Google Play) may be a key mediator in the adoption of mobile travel and tourism services both from a traveler and a service provider perspective. Moreover, it must be remembered that many device and mobile operating system developers want service providers to specifically create services for their platforms and see native applications as a strategic advantage to sell more devices of a certain kind. The mobile telecom industry has moved into a battle of ecosystems where device makers, developers of operating systems and service developers are to some extent forced to choose their development platforms.