18 resultados para Factor Model

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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Tutkimuksen tavoitteena oli tunnistaa tutkittavan yrityksen (Starlike Oy) avainasiakassuhteiden tila sekä luoda strategioita näiden asiakassuhteiden kehittämiseksi. Asiakassuhteiden tilaa pyrittiin analysoimaan tarkastelemalla kolmea suhteen osatekijää; ilmapiiriä, transaktiohistoriaa ja toimijoita. Vastaavasti strategioiden luonnintukena käytettiin asiakassuhteen osatekijöiden painoarvo- sekä asiakassuhteen ongelmat/tarpeet -mallia. Tutkimusmenetelmänä käytettiin kyselytutkimusta, jonka aineisto kerättiin sähköpostikyselyllä syksyn 2006 aikana niin asiakkailta kuin yritykseltäkin. Asiakassuhteiden havaittiin jakautuvan viidelle tasolle jakauman noudattaessa normaalijakaumaa. Asiakkaan ja myyjän näkemyksissä asiakassuhteen nykytilasta ei havaittu olevan järjestelmällistä eroa. Toisaalta myyjän havaittiin asettavan asiakassuhteen tavoitteet järjestelmällisesti asiakasta korkeammalle. Asiakassuhteiden tavoitteiden havaittiin lisäksi jakautuvan asiakassuhteen tasoittain kahteen osaan siten, että noin puolet asiakkaista halusi kehittää asiakassuhdettaan ja noin puolet oli tyytyväisiä sen nykytilaan.

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Tutkimuksen tavoitteena on selvittää, esiintyykö suomeen sijoittavilla osakerahastoilla menestyksen pysyvyyttä. Tutkimusaineisto koostuu kaikista suomalaisista osakerahastoista, jotka toimivat ajanjaksolla 15.1.1998-13.1.2005. Aineisto on vapaa selviytymisvinoumasta. Suorituskyvyn mittareina käytetään CAPM-alfaa sekä kolmi- ja nelifaktori-alfaa. Empiirisessä osassa osakerahastojen menestyksen pysyvyyttä testataan Spearmanin järjestyskorrelaatiotestillä. Evidenssi menestyksen pysyvyydestä jäi vähäiseksi, vaikkakin sitä esiintyi satunnaisesti kaikilla menestysmittareilla joillakin ranking- ja sijoitusperiodin yhdistelmillä. CAPM-alfalla tarkasteltuna tilastollisesti merkitsevää menestyksen pysyvyyttä esiintyi selvästi useammin kuin muilla menestysmittareilla. Tulokset tukevat viimeaikaisia kansainvälisiä tutkimuksia, joiden mukaan menestyksen pysyvyys riippuu usein mittaustavasta. Menestysmittareina käytettyjen regressiomallien merkitsevyystestit osoittavat multifaktorimallien selittävän osakerahastojen tuottoja CAPM:a paremmin. Lisätyt muuttujat parantavat merkittävästi CAPM:n selitysvoimaa.

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Tutkielman tavoitteena on testata kvantitatiivisen osakepisteytysmallin tehokkuutta Euroopan osakemarkkinoilla. Osakepisteytysmalli järjestää osakkeet paremmuusjärjestykseen yrityskohtaisten tunnuslukujen avulla. Pisteytysmallin suositusten mukaan luodaan testisalkku ajanjaksolta 2002 2007. Testisalkun tuottoa mitataan pääomahyödykkeiden hinnoittelumallin sekä Faman ja Frenchin kolmen faktorin mallin avulla. Testisalkkua testataan markkina arvopainoisena sekä tasapainoisena. Tasapainoisessa salkussa jokaista osaketta painotetaan yhtäläisesti. Testisalkun rinnalle luodaan lisäksi vertailusalkku satunnaisista osakkeista. Tasapainotettu testisalkku tuotti tarkasteluajanjaksolla tilastollisesti merkitsevää markkinariskikorjattua ylituottoa 0,7 prosenttia kuukaudessa. Kolmen faktorin mallin avulla laskettu ylituotto ei ollut merkitsevä. Yrityskokofaktori sekä markkinatuotto näyttivät selittävän vahvasti testisalkun tuottoja. Yrityskoon vaikutus näkyi myös markkina arvopainotetussa salkussa, jonka tuotto ei päihittänyt markkinatuottoa. Vertailusalkku ei tuottanut tilastollisesti merkitsevää ylituottoa.

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Tämän tutkimuksen tarkoituksena on selvittää mitkä tekijät ovat mikroyrityksen kasvun edellytyksenä ja mitkä tekijät ovat kasvun esteinä. Tutkimuksen taustalla on mikroyritysten yleisesti vähäinen kasvuhalukkuus. Tässä tutkimuksessa yrittäjien kasvuaikomuksia tarkastellaan kasvun prosessimalliin tukeutuen ja mikroyritysten kasvuun vaikuttavia tekijöitä tarkastellaan Perrenin mikroyrityksen kasvuun vaikuttavien tekijöiden mallin avulla. Tutkimuksessa on käytetty kvalitatiivista tutkimusmenetelmää. Tutkimus on toteutettu haastattelututkimuksena, jossa on haastateltu mikroyrittäjiä Päijät-Hämeessä Lahden ja Hollolan alueilla. Tämän tutkimuksen mukaan mikroyritysten kasvuun vaikuttavat yrittäjän tahtotila ja kyky yrityksen kehittämiseen sekä yrittäjän riskinottokyky että suotuisat ympäristölliset olosuhteet. Näiden tekijöiden puuttuminen estää kasvun. Yrityksen kasvua estäviä muita tekijöitä ovat tutkimuksen mukaan mikroyritysten liiallinen paikallisuus, yhteistyön vähäisyys sekä yrittäjän liiallinen kietoutuminen liiketoimintaan että toiminnan liian vähäinen strateginen suunnittelu.

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Female sexual dysfunctions, including desire, arousal, orgasm and pain problems, have been shown to be highly prevalent among women around the world. The etiology of these dysfunctions is unclear but associations with health, age, psychological problems, and relationship factors have been identified. Genetic effects explain individual variation in orgasm function to some extent but until now quantitative behavior genetic analyses have not been applied to other sexual functions. In addition, behavior genetics can be applied to exploring the cause of any observed comorbidity between the dysfunctions. Discovering more about the etiology of the dysfunctions may further improve the classification systems which are currently under intense debate. The aims of the present thesis were to evaluate the psychometric properties of a Finnish-language version of a commonly used questionnaire for measuring female sexual function, the Female Sexual Function Index (FSFI), in order to investigate prevalence, comorbidity, and classification, and to explore the balance of genetic and environmental factors in the etiology as well as the associations of a number of biopsychosocial factors with female sexual functions. Female sexual functions were studied through survey methods in a population based sample of Finnish twins and their female siblings. There were two waves of data collection. The first data collection targeted 5,000 female twins aged 33–43 years and the second 7,680 female twins aged 18–33 and their over 18–year-old female siblings (n = 3,983). There was no overlap between the data collections. The combined overall response rate for both data collections was 53% (n = 8,868), with a better response rate in the second (57%) compared to the first (45%). In order to measure female sexual function, the FSFI was used. It includes 19 items which measure female sexual function during the previous four weeks in six subdomains; desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain. In line with earlier research in clinical populations, a six factor solution of the Finnish-language version of the FSFI received supported. The internal consistencies of the scales were good to excellent. Some questions about how to avoid overestimating the prevalence of extreme dysfunctions due to women being allocated the score of zero if they had had no sexual activity during the preceding four weeks were raised. The prevalence of female sexual dysfunctions per se ranged from 11% for lubrication dysfunction to 55% for desire dysfunction. The prevalence rates for sexual dysfunction with concomitant sexual distress, in other words, sexual disorders were notably lower ranging from 7% for lubrication disorder to 23% for desire disorder. The comorbidity between the dysfunctions was substantial most notably between arousal and lubrication dysfunction even if these two dysfunctions showed distinct patterns of associations with the other dysfunctions. Genetic influences on individual variation in the six subdomains of FSFI were modest but significant ranging from 3–11% for additive genetic effects and 5–18% for nonadditive genetic effects. The rest of the variation in sexual functions was explained by nonshared environmental influences. A correlated factor model, including additive and nonadditive genetic effects and nonshared environmental effects had the best fit. All in all, every correlation between the genetic factors was significant except between lubrication and pain. All correlations between the nonshared environment factors were significant showing that there is a substantial overlap in genetic and nonshared environmental influences between the dysfunctions. In general, psychological problems, poor satisfaction with the relationship, sexual distress, and poor partner compatibility were associated with more sexual dysfunctions. Age was confounded with relationship length but had over and above relationship length a negative effect on desire and sexual satisfaction and a positive effect on orgasm and pain functions. Alcohol consumption in general was associated with better desire, arousal, lubrication, and orgasm function. Women pregnant with their first child had fewer pain problems than nulliparous nonpregnant women. Multiparous pregnant women had more orgasm problems compared to multiparous nonpregnant women. Having children was associated with less orgasm and pain problems. The conclusions were that desire, subjective arousal, lubrication, orgasm, sexual satisfaction, and pain are separate entities that have distinct associations with a number of different biopsychosocial factors. However, there is also considerable comorbidity between the dysfunctions which are explained by overlap in additive genetic, nonadditive genetic and nonshared environmental influences. Sexual dysfunctions are highly prevalent and are not always associated with sexual distress and this relationship might be moderated by a good relationship and compatibility with partner. Regarding classification, the results supports separate diagnoses for subjective arousal and genital arousal as well as the inclusion of pain under sexual dysfunctions.

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The thesis examines the performance persistence of hedge funds using complement methodologies (namely cross-sectional regressions, quantile portfolio analysis and Spearman rank correlation test). In addition, six performance ranking metrics and six different combinations of selection and holding periods are compared. The data is gathered from HFI and Tremont databases covering over 14,000 hedge funds and time horizon is set from January 1996 to December 2007. The results suggest that there definitely exists performance persistence among hedge funds and the strength and existence of persistence vary among fund styles. The persistence depends on the metrics and combination of selection and prediction period applied. According to the results, the combination of 36-month selection and holding period outperforms other five period combinations in capturing performance persistence within the sample. Furthermore, model-free performance metrics capture persistence more sensitively than model-specific metrics. The study is the first one ever to use MVR as a performance ranking metric, and surprisingly MVR is more sensitive to detect persistence than other performance metrics employed.

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Tämä kandidaatintutkielma käsittelee yrityksen kokoon ja book-to-market arvoon perustuvia anomalioita Yhdysvaltojen osakemarkkinoilla. Tutkimuksen kohteena on epänormaalien tuottojen saavuttaminen kyseisten anomalioiden kautta erityisesti finanssikriisin aikana. Osakeportfolioiden analysointi tapahtuu pääasiassa Fama-French kolmifaktorimallin avulla.

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Tutkimuksessa tarkastellaan voidaanko Piotroskin (2000) kehittämää F-scorea käyttämällä saada arvostrategiaa parempia tuottoja Frankfurtin pörssissä 1998 – 2012. Arvostrategiaa määrittävinä tunnuslukuina käytetään P/E- ja P/B-lukujen käänteislukuja sekä niistä muodostettua yhdistelmätunnuslukua. Tunnusluvuille luodaan yhden, kahden ja kolmen vuoden sijoitusstrategiat, joiden menestymistä verrataan toisiinsa. Tuloksien perusteella voidaan todeta F-scoren olevan hyödyllisin P/B-lukuun yhdistettynä ja P/E-lukuun sovellettuna hyödytön. P/B-luvun kohdalla F-scoren ylituotto arvostrategiaan nähden on 9,60 prosenttiyksikköä. Vuotuinen tuotto P/B-luvun F-scoren strategialle on 23,16 %. Paras riskiin suhteutettu (oikaistu Sharpe) tulos on P/B-luvun yhden vuoden F-scoren strategialla (0,3414). Kolmifaktorimallin estimoimien ylituottojen erot ovat marginaalisen pieniä F-scoren ja arvostrategian välillä. Sijoitushorisontin osalta yhden vuoden pitoaika on menestyksekkäin kaikkien tutkimuksessa käytettyjen tunnuslukujen mukaan.

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In order that the radius and thus ununiform structure of the teeth and otherelectrical and magnetic parts of the machine may be taken into consideration the calculation of an axial flux permanent magnet machine is, conventionally, doneby means of 3D FEM-methods. This calculation procedure, however, requires a lotof time and computer recourses. This study proves that also analytical methods can be applied to perform the calculation successfully. The procedure of the analytical calculation can be summarized into following steps: first the magnet is divided into slices, which makes the calculation for each section individually, and then the parts are submitted to calculation of the final results. It is obvious that using this method can save a lot of designing and calculating time. Thecalculation program is designed to model the magnetic and electrical circuits of surface mounted axial flux permanent magnet synchronous machines in such a way, that it takes into account possible magnetic saturation of the iron parts. Theresult of the calculation is the torque of the motor including the vibrations. The motor geometry and the materials and either the torque or pole angle are defined and the motor can be fed with an arbitrary shape and amplitude of three-phase currents. There are no limits for the size and number of the pole pairs nor for many other factors. The calculation steps and the number of different sections of the magnet are selectable, but the calculation time is strongly depending on this. The results are compared to the measurements of real prototypes. The permanent magnet creates part of the flux in the magnetic circuit. The form and amplitude of the flux density in the air-gap depends on the geometry and material of the magnetic circuit, on the length of the air-gap and remanence flux density of the magnet. Slotting is taken into account by using the Carter factor in the slot opening area. The calculation is simple and fast if the shape of the magnetis a square and has no skew in relation to the stator slots. With a more complicated magnet shape the calculation has to be done in several sections. It is clear that according to the increasing number of sections also the result will become more accurate. In a radial flux motor all sections of the magnets create force with a same radius. In the case of an axial flux motor, each radial section creates force with a different radius and the torque is the sum of these. The magnetic circuit of the motor, consisting of the stator iron, rotor iron, air-gap, magnet and the slot, is modelled with a reluctance net, which considers the saturation of the iron. This means, that several iterations, in which the permeability is updated, has to be done in order to get final results. The motor torque is calculated using the instantaneous linkage flux and stator currents. Flux linkage is called the part of the flux that is created by the permanent magnets and the stator currents passing through the coils in stator teeth. The angle between this flux and the phase currents define the torque created by the magnetic circuit. Due to the winding structure of the stator and in order to limit the leakage flux the slot openings of the stator are normally not made of ferromagnetic material even though, in some cases, semimagnetic slot wedges are used. In the slot opening faces the flux enters the iron almost normally (tangentially with respect to the rotor flux) creating tangential forces in the rotor. This phenomenon iscalled cogging. The flux in the slot opening area on the different sides of theopening and in the different slot openings is not equal and so these forces do not compensate each other. In the calculation it is assumed that the flux entering the left side of the opening is the component left from the geometrical centre of the slot. This torque component together with the torque component calculated using the Lorenz force make the total torque of the motor. It is easy to assume that when all the magnet edges, where the derivative component of the magnet flux density is at its highest, enter the slot openings at the same time, this will have as a result a considerable cogging torque. To reduce the cogging torquethe magnet edges can be shaped so that they are not parallel to the stator slots, which is the common way to solve the problem. In doing so, the edge may be spread along the whole slot pitch and thus also the high derivative component willbe spread to occur equally along the rotation. Besides forming the magnets theymay also be placed somewhat asymmetric on the rotor surface. The asymmetric distribution can be made in many different ways. All the magnets may have a different deflection of the symmetrical centre point or they can be for example shiftedin pairs. There are some factors that limit the deflection. The first is that the magnets cannot overlap. The magnet shape and the relative width compared to the pole define the deflection in this case. The other factor is that a shifting of the poles limits the maximum torque of the motor. If the edges of adjacent magnets are very close to each other the leakage flux from one pole to the other increases reducing thus the air-gap magnetization. The asymmetric model needs some assumptions and simplifications in order to limit the size of the model and calculation time. The reluctance net is made for symmetric distribution. If the magnets are distributed asymmetrically the flux in the different pole pairs will not be exactly the same. Therefore, the assumption that the flux flows from the edges of the model to the next pole pairs, in the calculation model from one edgeto the other, is not correct. If it were wished for that this fact should be considered in multi-pole pair machines, this would mean that all the poles, in other words the whole machine, should be modelled in reluctance net. The error resulting from this wrong assumption is, nevertheless, irrelevant.

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Tutkielman tavoitteena on luoda liiketoimintamalli, joka tukee langattomien matkaviestintäpalveluiden markkinoiden luomista kehittyvillä markkinoilla. Teoreettinen osa tarkastelee langattomien matkaviestintäpalveluiden liiketoimintamallin kehittämisen tärkeimpiä elementtejä CIS maissa. Teoreettisen kappaleen tuloksena saadaan puitteet, jonka avulla liiketoimintamalli matkaviestintäpalveluille voidaan kehittää. Tutkielman empiirinen osa on toteutettu case tutkimuksena, jonka tavoitteena on ollut langattomien matkaviestintäpalvelujen markkinoiden luominen CIS maissa. Pääasiallinen empiirisen tiedon lähde on ollut teemahaastattelut. Tuloksena saatuja empiirisen osan tietoja verrataan teoriakappaleen vastaaviin tuloksiin Tulokset osoittavat, että radikaalin korkean teknologian innovaation markkinoiden luominen on hidas prosessi, joka vaatii kärsivällisyyttä yritykseltä. Markkinoiden, teknologian ja strategian epävarmuustekijät tuovat epävarmuutta kehittyvälle toimialalle ja markkinoille, joka vaikeuttaa liiketoimintamallin kehittämistä. Tärkein tekijä on palvelujen markkinointi ennemmin kuin teknologian. Avain kyvykkyys markkinoiden luomisessa on oppiminen, ei tietäminen.

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Tutkielman tarkoituksena on tutkia case-organisaationa toimivan Itäisen tullipiirin strategista uudistumiskykyä. Minkälaiset lähtökohdat organisaatiolla on kohdata tulevaisuuden haasteet omassa toimintaympäristössään ja minkälaisia esteitä uudistumiselle löytyy? Pärjätäkseen kiristyvässä kilpailussa on uudistumiseen vaikuttavien tekijöiden, kuten osaamisen, tiedon kulun, johtamisen ja suhteiden tunnistaminen ja hyödyntäminen ensiarvoisen tärkeää myös julkishallinnon organisaatioille. Tässä tutkielmassa uudistumiskykyä tarkastellaan kolmiulotteisen organisaatiomallin (mekaaninen, orgaaninen ja dynaaminen) valossa ja kehittämistoimien lähtökohtana pidetään organisaation omaa strategista fokusta. Tutkimus- ja tiedonkeruumenetelminä käytetään kvantitatiiviseksi luokiteltavaa, sähköisessä muodossa tehtävää KM-factor -kyselyä ja kvalitatiivista teemahaastattelua. Tutkimustulokset antavat strategisesti tärkeää tietoa case-organisaation nykytilasta; sen heikkouksista ja vahvuuksista. Tulosten perusteella organisaation toimintatapa on melko yhtenäinen ja strategisen fokuksensa, eli orgaanisen toimintaympäristön vaatimusten mukainen. Kehittämistoimia tulee kuitenkin kohdentaa erityisesti henkilöstön strategian mukaisen osaamisen ja esimiesten tiedon kulun lisäämiseen sekä yleisesti työmotivaatiotason nostamiseen koko kohdeorganisaatiossa. Organisaatiossa on luotava käytäntöjä, jotka tukevat avoimen tiedon kulun ilmapiiriä ja dialogimaista kommunikointia, jotta organisaation uudistumiskyky yhtenäisenä systeeminä parantuisi entisestään.

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The objective of the thesis was to develop a competitors’ financial performance monitoring model for management reporting. The research consisted of the selections of the comparison group and the performance meters as well as the actual creation of the model. A brief analysis of the current situation was also made. The aim of the results was to improve the financial reporting quality in the case organization by adding external business environment observation to the management reports. The comparison group for the case company was selected to include five companies that were all involved in power equipment engineering and project type business. The most limiting factor related to the comparison group selection was the availability of quarterly financial reporting. The most suitable performance meters were defined to be the developments of revenue, order backlog and EBITDA. These meters should be monitored systematically on quarterly basis and reported to the company management in a brief and informative way. The monitoring model was based on spreadsheet construction with key characteristics being usability, flexibility and simplicity. The model acts as a centered storage for financial competitor information as well as a reporting tool. The current market situation is strongly affected by the economic boom in the recent years and future challenges can be clearly seen in declining order backlogs. The case company has succeeded well related to its comparison group during the observation period since its business volume and profitability have developed in the best way.

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Protein homeostasis is essential for cells to prosper and survive. Various forms of stress, such as elevated temperatures, oxidative stress, heavy metals or bacterial infections cause protein damage, which might lead to improper folding and formation of toxic protein aggregates. Protein aggregation is associated with serious pathological conditions such as Alzheimer’s and Huntington’s disease. The heat shock response is a defense mechanism that protects the cell against protein-damaging stress. Its ancient origin and high conservation among eukaryotes suggest that the response is crucial for survival. The main regulator of the heat shock response is the transcription factor heat shock factor 1 (HSF1), which induces transcription of genes encoding protective molecular chaperones. In vertebrates, a family of four HSFs exists (HSF1-4), with versatile functions not only in coping with acute stress, but also in development, longevity and cancer. Thus, knowledge of the HSFs will aid in our understanding on how cells survive suboptimal circumstances, but will also provide insights into normal physiological processes as well as diseaseassociated conditions. In this study, the function and regulation of HSF2 have been investigated. Earlier gene inactivation experiments in mice have revealed roles for HSF2 in development, particularly in corticogenesis and spermatogenesis. Here, we demonstrate that HSF2 holds a role also in the heat shock response and influences stress-induced expression of heat shock proteins. Intriguingly, DNA-binding activity of HSF2 upon stress was dependent on the presence of intact HSF1, suggesting functional interplay between HSF1 and HSF2. The underlying mechanism for this phenomenon could be configuration of heterotrimers between the two factors, a possibility that was experimentally verified. By changing the levels of HSF2, the expression of HSF1-HSF2 heterotrimer target genes was altered, implementing HSF2 as a modulator of HSF-mediated transcription. The results further indicate that HSF2 activity is dependent on its concentration, which led us to ask the question of how accurate HSF2 levels are achieved. Using mouse spermatogenesis as a model system, HSF2 was found to be under direct control of miR-18, a miRNA belonging to the miR-17~92 cluster/Oncomir-1 and whose physiological function had remained unclear. Investigations on spermatogenesis are severely hampered by the lack of cell systems that would mimic the complex differentiation processes that constitute male germ cell development. Therefore, to verify that HSF2 is regulated by miR-18 in spermatogenesis, a novel method named T-GIST (Transfection of Germ cells in Intact Seminiferous Tubules) was developed. Employing this method, the functional consequences of miR-18-mediated regulation in vivo were demonstrated; inhibition of miR- 18 led to increased expression of HSF2 and altered the expression of HSF2 target genes Ssty2 and Speer4a. Consequently, the results link miR-18 to HSF2-mediated processes such as germ cell maturation and quality control and provide miR-18 with a physiological role in gene expression during spermatogenesis.Taken together, this study presents compelling evidence that HSF2 is a transcriptional regulator in the heat shock response and establishes the concept of physical interplay between HSF2 and HSF1 and functional consequences thereof. This is also the first study describing miRNA-mediated regulation of an HSF.

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Fibroblast growth factors (FGFs) are involved in the development and homeostasis of the prostate and other reproductive organs. FGF signaling is altered in prostate cancer. Fibroblast growth factor 8 (FGF8) is a mitogenic growth factor and its expression is elevated in prostate cancer and in premalignant prostatic intraepithelial neoplasia (PIN) lesions. FGF8b is the most transforming isoform of FGF8. Experimental models show that FGF8b promotes several phases of prostate tumorigenesis - including cancer initiation, tumor growth, angiogenesis, invasion and development of bone metastasis. The mechanisms activated by FGF8b in the prostate are unclear. In the present study, to examine the tumorigenic effects of FGF8b on the prostate and other FGF8b expressing organs, an FGF8b transgenic (TG) mouse model was generated. The effect of estrogen receptor beta (ERβ) deficiency on FGF8binduced prostate tumorigenesis was studied by breeding FGF8b-TG mice with ERβ knockout mice (BERKOFVB). Overexpression of FGF8b caused progressive histological and morphological changes in the prostate, epididymis and testis of FGF8b-TG-mice. In the prostate, hyperplastic, preneoplastic and neoplastic changes, including mouse PIN (mPIN) lesions, adenocarcinomas, sarcomas and carcinosarcomas were present in the epithelium and stroma. In the epididymis, a highly cancer-resistant tissue, the epithelium contained dysplasias and the stroma had neoplasias and hyperplasias with atypical cells. Besides similar histological changes in the prostate and epididymis, overexpression of FGF8b induced similar changes in the expression of genes such as osteopontin (Spp1), connective tissue growth factor (Ctgf) and FGF receptors (Fgfrs) in these two tissues. In the testes of the FGF8b-TG mice, the seminiferous epithelium was frequently degenerative and the number of spermatids was decreased. A portion of the FGF8b-TG male mice was infertile. Deficiency of ERβ did not accelerate prostate tumorigenesis in the FGF8b-TG mice, but increased significantly the frequency of mucinous metaplasia and slightly the frequency of inflammation in the prostate. This suggests putative differentiation promoting and anti-inflammatory roles for ERβ. In summary, these results underscore the importance of FGF signaling in male reproductive organs and provide novel evidence for a role of FGF8b in stromal activation and prostate tumorigenesis.

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This study is a qualitative action research by its nature with elements of personal design in the form of a tangible model implementation framework construction. Utilized empirical data has been gathered via two questionnaires in relation to the arranged four workshop events with twelve individual participants. Five of them represented maintenance customers, three maintenance service providers and four equipment providers respectively. Further, there are two main research objectives in proportion to the two complementary focusing areas of this thesis. Firstly, the value-based life-cycle model, which first version has already been developed prior to this thesis, requires updating in order to increase its real-life applicability as an inter-firm decision-making tool in industrial maintenance. This first research objective is fulfilled by improving appearance, intelligibility and usability of the above-mentioned model. In addition, certain new features are also added. The workshop participants from the collaborating companies were reasonably pleased with made changes, although further attention will be required in future on the model’s intelligibility in particular as main results, charts and values were all reckoned as slightly hard to understand. Moreover, upgraded model’s appearance and added new features satisfied them the most. Secondly and more importantly, the premises of the model’s possible inter-firm implementation process need to be considered. This second research objective is delivered in two consecutive steps. At first, a bipartite open-books supported implementation framework is created and its different characteristics discussed in theory. Afterwards, the prerequisites and the pitfalls of increasing inter-organizational information transparency are studied in empirical context. One of the main findings was that the organizations are not yet prepared for network-wide information disclosure as dyadic collaboration was favored instead. However, they would be willing to share information bilaterally at least. Another major result was that the present state of companies’ cost accounting systems will definitely need implementation-wise enhancing in future since accurate and sufficiently detailed maintenance data is not available. Further, it will also be crucial to create supporting and mutually agreed network infrastructure. There are hardly any collaborative models, methods or tools currently in usage. Lastly, the essential questions about mutual trust and predominant purchasing strategies are cooperation-wise important. If inter-organizational activities are expanded, a more relational approach should be favored in this regard. Mutual trust was also recognized as a significant cooperation factor, but it is hard to measure in reality.