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Tutkimuksessa on tarkasteltu nuorten maahanmuuttajien etnistä identifioitumista sekä sitä, miten he määrittelevät rasismin omien kokemustensa kautta. Analyysi jakautuu kahteen osaan: nuorten identteettipohdintoihin ja rasismin reflektoimiseen. Tutkimuksen kysymyksenasettelu nousee Karmela Liebkindin ja Inga Jasinskaja-Lahden vuonna 1997 tekemästä tutkimuksesta Maahanmuuttajien sopeutuminen pääkaupunkiseudulla. Tutkimuksen mukaan syrjintä ja rasismi ovat merkittävällä tavalla yhteydessä maahanmuuttajien yleiseen psyykkiseen hyvinvointiin. Esimerkiksi nuoret maahanmuuttajat (11-22-vuotiaat) ovat erityisen haavoittuvaisia sekä uuteen maahan tullessaan että siellä ollessaan. Empiirinen aineisto on kerätty teemahaastatteluiden avulla. Tutkimuksen 12 haastateltavaa (6 poikaa ja 6 tyttöä) kävivät haastatteluhetkellä helsinkiläistä lukiota ja olivat 16-19-vuoden ikäisiä. Haastateltavat ovat kotoisin entisen Neuvostoliiton alueelta (5), Somaliasta (4), Vietnamista (1), Hongkongista (1) ja Irakista (1) ja heidän Suomeen tuloikänsä vaihtelee 5-16-vuoden välillä. Haastattelukielioli suomi. Haastatteluaineisto on analysoitu teema-analyysin avulla. Aineistosta etsittiin kohtia, joissa nuoret puhuvat etnisestä identifioitumisestaan suhteessa sekä omaan taustaan että suomalaisuuteen. Lisäksi analyysissa kiinnitettiin huomiota siihen, millaisia näkemyksiä nuoret esittivät rasismista, maahanmuuttopolitiikasta ja ulkomaalaisasenteista ja miten nämä näkemykset ovat yhteneväisiä sekä miten ne eroavat toisistaan. Nuorten etnisyyspohdintoja kuvaavat toisaalta etnisyyden tilannesidonnaisuus ja toisaalta etnisyyden vahva yhteys syntyperään. Etnisyyden saama merkitys vaihtelee sosiaalisten ympäristöjen vaihtuessa. Pohtimalla suomalaisuuden ja suomalaisten tyypillisiä piirteitä nuoret pystyivät helpommin jäsentämään myös omaa kuulumistaan tiettyyn ryhmään. Varsinkin silloin kun suomalaisuus ymmärrettiin kansalaisuudeksi, sitä pidettiin lähes poikkeuksetta syntyperäisten suomalaisten etuoikeutena. Tunnepitoinen ja jopa vereen sidottu etnisyys korostui ennen kaikkea niissä aineiston kohdissa, joissa nuoret pohtivat suomalaiseksi muuttumista ja tulemista. Kukaan haastateltavista ei uskonut muuttuvansa kunnon suomalaiseksi, mikä edellyttäisi toisaalta kokemuksen suomalaisuudesta ja toisaalta hyväksynnän ulkoapäin. Haastateltavat pohtivat vastahakoisesti suomalaisuuden ja suomalaisten negatiivisia piirteitä. Monet mainitsivat asenteellisen ja rasistisen suhtautumisen ulkomaalaisiin, maahanmuuttajiin ja vähemmistöjen edustajiin, kun he puhuivat niistä tilanteista, joissa he häpeävät suomalaisia. Rasismia ei kuitenkaan haluttu yleistää suomalaisten ryhmäominaisuudeksi, vaan sitä pidettiin "poikkeuksellisten" suomalaisten (esimerkiksi skinien) ominaisuutena. Arjen rasistisista selkkauksista puhuttaessa nuoret vähättelivät tapahtumien vakavuutta ja pyrkivät ymmärtämään rasistista käyttäytymistä ja pitivät sitä luonnollisena. Joissakin tapauksissa haastateltavat sanoivat olevansa liian herkkiä rasismille ja päättelivät, etteivät vihamielisyydet alunperin olleet tarkoituksellisia. Rasismin ristiriitaisuutta uhrin kannalta kuvaa tutkimuksessa se, että rasismikokemuksia pidettiin nöyryyttävinä ja hävettävinä, ja sen takia niistä myös vaiettiin kotona. Tutkimuksen perusteella näyttää siltä, että rasismi on ymmärrettävä tapahtumaketjuna eikä yksittäisinä ja erillisinä tapauksina. Tutkimuksessa ilmeni, että nuorten rasismia koskeviin pohdintoihin vaikuttaa se, millä tavoin yhteiskunnan yleinen ja virallinen ilmapiiri reagoi rasismiin. Rasismin ja syrjinnän hiljainen hyväksyminen saattaa vaikuttaa siihen, että myös uhrit vähättelevät rasismikokemuksia. Avainsanat: Nuoret maahanmuuttajat, etnisyys, kulttuuri, rasismi, teemahaastattelu

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Pastoraalikirjeissä eli 1. ja 2. Timoteuskirjeessä ja Tituksen kirjeessä naisten seurakunnallista vaikutusvaltaa rajoitetaan kolmella tavalla: 1. keskittämällä naisten tehtävät kotiin, 2. kieltämällä naisilta opettaminen ja hallitseminen sekä 3. rajoittamalla naiset virkojen ulkopuolelle. Kirjoittaja perustelee kotiin sijoittuvia tehtäviä sillä, että ne ovat 1. oikean opin mukaisia ja 2. ulkopuolisten silmissä oikein. Kreikkalais-roomalaisessa yhteiskunnassa itäisten uskontojen - joihin kristinusko myös kuului - pelättiin vaikuttavan erityisesti naisiin negatiivisesti. Siksi huoli kristinuskon maineesta ei ollut turha. Hyvä maine oli kristityille tärkeää, jotta he saisivat elää rauhassa ja levittää uskontoaan. Kirjoittajan käsitykset ovat samassa linjassa yhteiskunnan lainsäätäjien ja filosofien käsitysten kanssa. Hän painottaa naisten paikaksi ja tehtäväksi samaa paikkaa ja samoja tehtäviä kuin mitä kreikkalais-roomalaisessa yhteiskunnassakin: kotia ja kotiin liittyviä tehtäviä. Kirjoittaja kieltää naiselta miehen opettamisen ja hallitsemisen. Hän perustelee kieltoaan naisen alempiarvoisuudella mieheen nähden. Argumentointi on teologista (kirjoittaja ottaa esimerkiksi luomis- ja syntiinlankeemuskertomuksen). Hänen tulkinnallaan on juuret juutalaisessa tulkinnassa synnin alkuperästä. Kirjoittajan ohjeistukset vastaavat kuitenkin myös kreikkalais-roomalaisia ihanteita ja käytäntöjä. Naisten julkinen puhuminen nähtiin yhteiskunnassa täysin sopimattomana. Käsitykseen voidaan löytää kaksi syytä: 1. Naisia koulutettiin merkittävästi vähemmän kuin miehiä ja siksi naiset eivät opettaneet miehiä 2. Naisten ajateltiin olevan luonnostaan alempiarvoisia miehiin nähden. Näin ollen jos nainen ja mies kuuluivat samaan sosiaaliluokkaan, mies oli aina naisen yläpuolella, eikä nainen saanut opettaa tai hallita miestä vaan päinvastoin. Itsenäiset, varakkaat naiset saattoivat opettaa alempiarvoisia miehiä myös seurakunnassa, kuten yhteiskunnassakin. Näyttää siltä, että kirjoittajan kieltojen ja kehotusten takana on jokin oikea seurakunnallinen tilanne. Pastoraalikirjeiden seurakuntien naiset eivät olleet käyttäytyneet yhteiskunnallisesti hyväksyttyjen standardien mukaisesti. Kolmanneksi kirjoittaja rajoittaa naisten mahdollisuutta toimia seurakunnallisissa viroissa. Kirjoittajan mukaan seurakunta on Jumalan huonekunta, jossa jokaisen jäsenen tulee käyttäytyä oman yhteiskunnallisen statuksensa mukaisesti. Näin ollen kirjoittaja asettaa niille, jotka pyrkivät seurakunnallisiin virkoihin, vaatimukset, jotka vain ylempiin yhteiskuntaluokkiin kuuluvat kristityt voivat täyttää. Viranhaltijoiden tulee olla talonomistajia, koulutettuja ja nauttia kunnioitusta yhteiskunnassa. Merkittävä osa naisista rajautuu näiden kriteerien johdosta virkojen ulkopuolelle. Vain harvat naiset olivat itsenäisiä ja niin varakkaita, että heillä oli oma huonekunta johdettavanaan. Kirjoittaja kuitenkin hyväksyy tällaiset naiset seurakunnallisiinkin tehtäviin: hän mainitsee naisdiakonit ja naisvanhimmat. Kirjoittaja uskoo vakaasti, että kreikkalais-roomalaisen yhteiskunnan hierarkia on sopusoinnussa kristillisen sanoman kanssa. Johtopäätökseni onkin, että seurakunnan jäsenille osoitetut käytösvaatimukset olivat ympäröivän yhteiskunnan sosiaalisen järjestyksen mukaisia. Naisten seurakunnallista vaikutusvaltaa rajoitettiin, koska vapaampi käytös ei olisi ollut yhteiskunnallisesti hyväksyttävää.

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This thesis is an assessment of the hoax hypothesis, mainly propagated in Stephen C. Carlson's 2005 monograph "The Gospel Hoax: Morton Smith's Invention of Secret Mark", which suggests that professor Morton Smith (1915-1991) forged Clement of Alexandria's letter to Theodore. This letter Smith claimed to have discovered as an 18th century copy in the monastery of Mar Saba in 1958. The Introduction narrates the discovery story of Morton Smith and traces the manuscript's whereabouts up to its apparent disappearance in 1990 following with a brief history of scholarship of the MS and some methodological considerations. Chapters 2 and 3 deal with the arguments for the hoax (mainly by Stephen C. Carlson) and against it (mainly Scott G. Brown). Chapter 2 looks at the MS in its physical aspects, and chapter 3 assesses its subject matter. I conclude that some of the details fit reasonably well with the hoax hypothesis, but on the whole the arguments against it are more persuasive. Especially Carlson's use of QDE-analysis (Questioned Document Examination) has many problems. Comparing the handwriting of Clement's letter to Morton Smith's handwriting I conclude that there are some "repeated differences" between them suggesting that Smith is not the writer of the disputed letter. Clement's letter to Theodore derives most likely from antiquity though the exact details of its character are not discussed in length in this thesis. In Chapter 4 I take a special look at Stephen C. Carlson's arguments which propose that Morton Smith hid clues of his identity to the MS and the materials surrounding it. Comparing these alleged clues to known pseudoscientific works I conclude that Carlson utilizes here methods normally reserved for building a conspiracy theory; thus Carlson's hoax hypothesis has serious methodological flaws in respect to these hidden clues. I construct a model of these questionable methods titled "a boisterous pseudohistorical method" that contains three parts: 1) beginning with a question that from the beginning implicitly contains the answer, 2) considering everything will do as evidence for the conspiracy theory, and 3) abandoning probability and thinking literally that everything is connected. I propose that Stephen C. Carlson utilizes these pseudoscientific methods in his unearthing of Morton Smith's "clues". Chapter 5 looks briefly at the literary genre I title "textual puzzle -thriller". Because even biblical scholarship follows the signs of the times, I propose Carlson's hoax hypothesis has its literary equivalents in fiction in titles like Dan Brown's "Da Vinci Code" and in academic works in titles like John Dart's "Decoding Mark". All of these are interested in solving textual puzzles, even though the methodological choices are not acceptable for scholarship. Thus the hoax hypothesis as a whole is alternatively either unpersuasive or plain bad science.

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Tässä tutkielmassa tutkin millaisen kuvan Francis Ford Coppolan ohjaamat kolme Kummisetä-elokuvaa ja David Chasen luoman Sopranos-televisiosarjan kaksi ensimmäistä tuotantokautta antavat roomalaiskatolisesta kirkosta ja erityisesti Amerikassa toimivasta roomalaiskatolisesta kirkosta. Kummisetä-elokuvat valmistuivat vuosina 1972, 1974 ja 1990, Sopranos-sarjan kaksi ensimmäistä tuotantokautta taas esitettiin HBO-kanavalla ensimmäisen kerran vuosina 1999 ja 2000. Lähteet kattavat Amerikan katolisen kirkon historian 1900-luvun alusta aina 2000-luvun alkuun asti. Pyrin vastaamaan tutkielmassani siihen, millaisena lähteet kuvaavat katolisen ja onko kuvaukselle löydettävissä jotain syitä. Kummisetä-elokuvien kohdalla on paradoksaalista se, että ne kaikki kuvaavat menneisyyden eivätkä tekohetkensä tapahtumia, mikä mahdollisesti näkyy myös niiden tavassa kuvata katolista kirkkoa. Vaikuttaisi siltä, että varsinkin kahden ensimmäisen Kummisetä-elokuvan tapa kuvata Amerikan katolista kirkkoa pohjautuu pitkälti elokuvan tekohetken tunnelmiin. Elokuvien ohjaaja Francis Ford Coppola on myöntänyt käyttäneensä Kummisetä-elokuvien päähenkilöinä olevaa Corleone-perhettä Amerikan vertauskuvana. Elokuvien yksi kattava teema on eräänlainen maallistumiskehitys, jossa vanhan polven edustajan, don Vito Corleonen, arvot syrjäytyvät ja tilalle nousee uusi johtajapolvi Viton nuorimman pojan don Michael Corleonen hahmossa. Michael Corleone edustaa huomattavasti armottomampaa polvea kuin Vito eikä uskonto ja katolinen kirkko näy hänen elämässään juuri lainkaan. Michaelin kyyninen ja kylmäkin hahmo on mitä todennäköisemmin vertauskuva elokuvien tekohetken yleisistä tunnelmia, jolloin Watergate-skandaali kansallisella tasolla ja Vatikaanin II konsiili ja paavin kiertokirje Humanae Vitae muokkasivat rajusti perinteisen katolisuuden ja amerikkalaisuuden identiteettiä. Kolmas Kummisetä-elokuva käsittelee lähes kokonaan paavi Johannes Paavali I:n lyhyeksi jäänyttä paaviuskautta vuodelta 1978 osittain fiktioin keinoin. Elokuvan yhtäläisyydet rikoskirjailija David Yallopin menestyskirjaan In Gods Name. An Investigation into the Murder of Pope John Paul I, jossa kirjailija esittää paavin tulleen kuurian virkamiesten ja mafiosoiden murhaamaksi, ovat selkeät. Kirkosta luodaan kuva toisaalta armottomona valtakoneistona, mutta toisaalta myös hengellisenä yhteisönä, josta katuvan ihmisen on mahdollisuus löytää apua. Sopranos-televisiosarja jatkaa kahdella ensimmäisellä tuotantokaudellaan saman maallistumiskehityksen kulkua kuin kaksi ensimmäistä Kummisetä-elokuvaakin. Päähenkilö Tony Soprano perheineen on lähes täysin irrallaan katolisesta perinteestä eivätkä he enää tunne sen oppejakaan kunnolla. Silti he mieltävät itsensä katolilaisiksi. Tämä vastaa joiltain osin tutkimustuloksia todellisista amerikkalaisista katolilaisista. Kaiken kaikkiaan Kummisetä-elokuvatrilogia ja Sopranos-televisiosarja antavat katolisesta kirkosta hyvin monipuolisen ja joissain asioissa totuudenmukaisenkin kuvan, joskin tekijöiden oma henkilöhistoria ja ajan skandaalit ovat väistämättä värittäneet kirkkokuvausta. Siten ne muodostavat värikkään läpileikkauksen Amerikan katolisen kirkon kehityksestä amerikanitalialaisessa yhteisössä 1900-luvun alusta 2000-luvun alkuun.

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Tämän tutkimuksen tarkoituksena on selvittää psykoottisen mielenterveyspotilaan uskonnonvapautta. Tutkimuskysymyksiä on kolme: Millä perusteilla psykoottisen potilaan uskonnonvapaus on turvattu ja millä perusteilla sitä rajoitetaan? Miten psykoottinen ja uskonnollinen todellisuudentulkinta eroavat toisistaan? Vaarantaako psykiatriseen todellisuudentulkintaan perustuva hoito potilaan negatiivisen uskonnonvapauden eli oikeuden elää ilman uskontoa? Tutkimusmetodina on systemaattinen analyysi. Lähteet ovat perustusoikeudet, mielenterveyslaki, potilaslaki, YK:n Principles for the protection of persons with mental illness and the improvement of mental health care, Maailman psykiatriyhdistyksen Madridin julistus ja Suomen mielenterveysseuran Mielenterveyspotilaan oikeudet. Uskonnonvapautta tarkastellaan tässä tutkimuksessa kahden eri vapauskäsityksen näkökulmasta: ulkoisena vapautena, joka edellyttää kompetenssia ja autenttisuutta, sekä ulkoisen ja sisäisen vapauden summana, johon kompetenssi ja autenttisuus sisältyvät. Psykoottisella potilaalla on ihmisyytensä ja kansalaisuutensa perusteella lähtökohtaisesti täysi uskonnonvapaus, mutta sitä voidaan rajoittaa. Jos uskonnonvapaus ymmärretään ulkoiseksi vapaudeksi, rajoittaa psykoottisen potilaan uskonnonvapautta tahdosta riippumattomassa hoidossa hänen terveytensä ja turvallisuutensa suojaaminen. Uskonnonvapauden rajoittaminen voidaan perustella sillä, ettei psykoottinen potilas täytä uskonnonvapauden edellytyksiä eli kompetenssia ja autenttisuutta, sillä, että potilaan terveyteen ja turvallisuuteen liittyvät oikeudet priorisoidaan uskonnonvapauden yläpuolelle sekä sillä, että pyritään terveyshyötyyn. Jos uskonnonvapaus ymmärretään ulkoisen ja sisäisen vapauden summaksi, on psykoosi uskonnonvapautta rajoittava tekijä, koska se tekee yksilöstä epäautenttisen ja puuttuu hänen kompetenssiinsa. Psykoosin (myös tahdosta riippumaton) hoito voidaan ymmärtää tällöin yritykseksi palauttaa uskonnonvapaus. Rajoittamalla ulkoista uskonnonvapautta pyritään maksimoimaan ulkoisen ja sisäisen uskonnonvapauden summa. Vaikka psykoottisella ja uskonnollisella todellisuudentulkinnalla on yhtäläisyyksiä, niiden toisistaan erottaminen on tärkeää, koska yksilöllä, jonka todellisuudentulkinta määritellään psykoottiseksi, on oikeus saada hoitoa, kun taas yksilön uskonnollista todellisuudentulkintaa suojaa uskonnonvapaus eikä sitä saa hoitaa sairautena. Lähteiden mukaan psykoottisen ja uskonnollisen todellisuudentulkinnan toisistaan erottaminen diagnostisten kriteerien ja lääketieteellisen tiedon avulla on lääkärin tehtävä. Tutkimuksessani esitän kaksi periaatetta, joiden avulla todellisuudentulkinnat voidaan erottaa toisistaan. Yksinäinen puu ei pala -periaatteen mukaan yksilön todellisuudentulkinta on uskonnollinen, mikäli se jaetaan jossain yhteisössä. Hedelmistään puu tunnetaan -periaatteen mukaan yksilön todellisuudentulkinta on uskonnollinen, mikäli sen terveydelliset ja sosiaaliset seuraukset ovat hyvät. Antipsykiatrinen kritiikki väittää psykiatrian olevan uskonto. Jos väite on tosi, puututaan tahdosta riippumattomassa hoidossa yksilön oikeuteen elää ilman uskontoa, sillä ko. hoidossa olevan psykoottisen potilaan on pakko suostua siihen, että häntä hoidetaan psykiatrian arvojen ja todellisuudentulkinnan mukaan. Vaikuttaa kuitenkin siltä, että jos psykiatria määritellään uskonnoksi, uskonnon käsite kärsii inflaation. Koska psykoottisen potilaan uskonnonvapaus on pohjimmiltaan eettinen kysymys, on tärkeää myöntää psykiatrian arvosidonnaisuus. Tällöin voidaan tehdä tietoisesti moraalisia päätöksiä ja kantaa moraalinen vastuu esimerkiksi diagnoosin määrittelyssä. Psykiatrian voidaan katsoa perustuvan universaaleihin arvoihin samalla tavalla kuin ihmisoikeuksienkin.

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In public economics, two extremist views on the functions of a government compete: one emphasizes government working for the public interest to provide value for the citizens, while another regards government mainly as a workhorse for private interests. Moreover, as the sole legitimate authority, the government has the right to define the rules and laws as well as to enforce them. With respect to regulation, two extremes arise: from too little regulation to too much of it. If the government does not function or ceases to exist, the state falls into anarchy or chaos (Somalia). If it regulates too much, it will completely suffocate private activities, which might be considered extralegal (the former Soviet Union). In this thesis I scrutinize the government s interventionist policies and evaluate the question of how to best promote economic well-being. The first two essays assume that the government s policies promote illegal activity. The first paper evaluates the interaction between the government and the mafia, and pays attention to the law enforcement of underground production. We show that the revenue-maximizing government will always monitor the shadow economy, as monitoring contributes to the government s revenue. In general, both legal and illegal firms are hurt by the entry of the mafia. It is, however, plausible that legal firms might benefit by the entry of the mafia if it competes with the government. The second paper tackles the issue of the measurement of the size of the shadow economy. To formulate policies it is essential to know what drives illegal economic activity; is it the tax burden, excess regulation, corruption or a weak legal environment? In this paper we propose an additional explanation for tax evasion and shadow production, namely cultural factors as manifested by religion as determinants of tax morality. According to our findings, Catholic and Protestant countries do not differ in their tax morale. The third paper contributes to the literature discussing the role of the government in promoting economic and productivity growth. Our main result is that, given the complex relationship between economic growth and economic freedom, marketization has not necessarily been beneficial in terms of growth. The last paper builds on traditional growth literature and revisits the debate on convergence clubs arising from demographic transition. We provide new evidence against the idea that countries within a club would converge over time. Instead, we propose that since the demographic transition is a dynamic process, one can expect countries to enter the last regime of stable, modern growth in stages.

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Glial cell line-derived neurotrophic factor (GDNF) and its family members neurturin (NRTN), artemin (ARTN) and persephin (PSPN) are growth factors, which are involved in the development, differentiation and maintenance of many neuron types. In addition, they function outside of the nervous system, e.g. in the development of kidney, testis and liver. GDNF family ligand (GFL) signalling happens through a tetrameric receptor complex, which includes two glycosylphosphatidylinositol (GPI)-anchored GDNF family receptor (GFRα) molecules and two RET (rearranged during transfection) receptor tyrosine kinases. Each of the ligands binds preferentially one of the four GFRα receptors: GDNF binds to GFRα1, NRTN to GFRα2, ARTN to GFRα3 and PSPN to GFRα4. The signal is then delivered by RET, which cannot bind the GFLs on its own, but can bind the GFL-GFRα complex. Under normal cellular conditions, RET is only phosphorylated on the cell surface after ligand binding. At least the GDNF-GFRα1 complex is believed to recruit RET to lipid rafts, where downstream signalling occurs. In general, GFRαs consist of three cysteine-rich domains, but all GFRα4s except for chicken GFRα4 lack domain 1 (D1). We characterised the biochemical and cell biological properties of mouse PSPN receptor GFRα4 and showed that it has a significantly weaker capacity than GFRα1 to recruit RET to the lipid rafts. In spite of that, it can phosphorylate RET in the presence of PSPN and contribute to neuronal differentiation and survival. Therefore, the recruitment of RET to the lipid rafts does not seem to be crucial for the biological activity of all GFRα receptors. Secondly, we demonstrated that GFRα1 D1 stabilises the GDNF-GFRα1 complex and thus affects the phosphorylation of RET and contributes to the biological activity. This may be important in physiological conditions, where the concentration of the ligand or the soluble GFRα1 receptor is low. Our results also suggest a role for D1 in heparin binding and, consequently, in the biodistribution of released GFRα1 or in the formation of the GFL-GFRα-RET complex. We also presented the crystallographic structure of GDNF in the complex with GFRα1 domains 2 and 3. The structure differs from the previously published ARTN-GFRα3 structure in three significant ways. The biochemical data verify the structure and reveal residues participating in the interactions between GFRα1 and GDNF, and preliminarily also between GFRα1 and RET and heparin. Finally, we showed that, the precursor of the oncogenic MEN 2B (multiple endocrine neoplasia type 2) form of RET gets phosphorylated already during its synthesis in the endoplasmic reticulum (ER). We also demonstrated that it associates with Src homology 2 domain-containing protein (SHC) and growth factor receptor-bound protein (GRB2) in the ER, and has the capacity to activate several downstream signalling molecules.

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It has been hypothesized that abuse of supra-therapeutic doses of anabolic androgenic steroids (AASs) can lead to dependence and function as a gateway to abuse of other drugs. This is supported by behavioral studies on animal models and psychiatric evaluations of human subjects, although their neurochemical effects remain largely unknown. A large body of evidence suggests that the ability of the drugs to induce a strong elevation of extracellular dopamine (DA) levels in the nucleus accumbens (NAc), especially, plays a crucial role in their reinforcing effects. -- This study had four main aims. The first was to explore the effects of nandrolone decanoate on dopaminergic and serotonergic activities in the brains of rats. The second aim was to assess whether or not nandrolone pre-exposure modulates the acute neurochemical and behavioral effects of psychostimulant drugs in experimental animals. The third was to investigate if the AAS-pre-treatment induced changes in brain reward circuitry are reversible. And the fourth main goal was to evaluate the role of androgen and estrogen receptors in the modulation of the dopaminergic and serotonergic effects of acute injections of stimulant drugs by sub-chronic nandrolone treatment. The results showed that nandrolone decanoate at doses, high enough to induce erythropoiesis, significantly increased the levels of DOPAC and 5-HT in the cerebral cortex. Co-administration of AAS and psychostimulant drugs showed that the increase in extracellular DA and 5-HT concentration evoked by amphetamine, MDMA and cocaine in the NAc was attenuated dose-dependently by pretreatment with nandrolone. Nandrolone pre-exposure also attenuated the ability of stimulants to cause increased stereotyped behavior and locomotor activity. Despite the significant decrease in nandrolone concentration in blood, the attenuation of cocaine’s effects remained unchanged after a fairly long period without nandrolone, suggesting that nandrolone effects could be long lasting. Blockade of androgen receptors with flutamide abolished the attenuating effect of nandrolone pretreatment on amphetamine-induced elevation of extracellular DA concentration. --- In conclusion, the results show that AAS-pretreatment is able to inhibit the reward-related neurochemical and behavioral effects of amphetamine, MDMA and cocaine in experimental animals. Furthermore, it seems that these effects could be long lasting and it appears that the ability of nandrolone to modulate reward-related effects of stimulants is dependent on activation of androgen receptors.

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Genetic studies on phylogeography and adaptive divergence in Northern Hemisphere fish species such as three-spined stickleback (Gasterosteus aculeatus) provide an excellent opportunity to investigate genetic mechanisms underlying population differentiation. According to the theory, the process of population differentiation results from a complex interplay between random and deterministic processes as well historical factors. The main scope in this thesis was to study how historical factors like the Pleistocene ice ages have shaped the patterns molecular diversity in three-spined stickleback populations in Europe and how this information could be utilized in the conservation genetic context. Furthermore, identifying footprints of natural selection at the DNA level might be used in identifying genes involved in evolutionary change. Overall, the results from phylogeographic studies indicate that the three-spined stickleback has colonized the Atlantic basin relatively recently but constitutes three major evolutionary lineages in Europe. In addition, the colonization of freshwater appears to result from multiple and independent invasions by the marine conspecifics. Molecular data together with morphology suggest that the most divergent freshwater populations are located in the Balkan Peninsula and these populations deserve a special conservation genetic status without warranting further taxonomical classification. In order to investigate the adaptive divergence in Fennoscandian three-spined stickleback populations several approaches were used. First, sequence variability in the Eda-gene, coding for the number of lateral plates, was concordant with the previously observed global pattern. Full plated allele is in high frequencies among marine populations whereas low plated allele dominates in the freshwater populations. Second, a microsatellite based genome scan identified both indications of balancing and directional selection in the three-spined stickleback genome, i.e. loci with unusually similar or unusually different allele frequencies over populations. The directionally selected loci were mainly associated with the adaptation to freshwater. A follow up study conducting a more detailed analysis in a chromosome region containing a putatively selected gene locus identified a fairly large genomic region affected by natural selection. However, this region contained several gene predictions, all of which might be the actual target of natural selection. All in all, the phylogeographic and adaptive divergence studies indicate that most of the genetic divergence has occurred in the freshwater populations whereas the marine populations have remained relatively uniform.

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The availability of oxygen has a major effect on all organisms. The yeast Saccharomyces cerevisiae is able to adapt its metabolism for growth in different conditions of oxygen provision, and to grow even under complete lack of oxygen. Although the physiology of S. cerevisiae has mainly been studied under fully aerobic and anaerobic conditions, less is known of metabolism under oxygen-limited conditions and of the adaptation to changing conditions of oxygen provision. This study compared the physiology of S. cerevisiae in conditions of five levels of oxygen provision (0, 0.5, 1.0, 2.8 and 20.9% O2 in feed gas) by using measurements on metabolite, transcriptome and proteome levels. On the transcriptional level, the main differences were observed between the three level groups, 0, 0.5 2.8 and 20.9% O2 which led to fully fermentative, respiro-fermentative and fully respiratory modes of metabolism, respectively. However, proteome analysis suggested post-transcriptional regulation at the level of 0.5 O2. The analysis of metabolite and transcript levels of central carbon metabolism also suggested post-transcriptional regulation especially in glycolysis. Further, a global upregulation of genes related to respiratory pathways was observed in the oxygen-limited conditions and the same trend was seen in the proteome analysis and in the activities of enzymes of the TCA cycle. The responses of intracellular metabolites related to central carbon metabolism and transcriptional responses to change in oxygen availability were studied. As a response to sudden oxygen depletion, concentrations of the metabolites of central carbon metabolism responded faster than the corresponding levels of gene expression. In general, the genome-wide transcriptional responses to oxygen depletion were highly similar when two different initial conditions of oxygen provision (20.9 and 1.0% O2) were compared. The genes related to growth and cell proliferation were transiently downregulated whereas the genes related to protein degradation and phosphate uptake were transiently upregulated. In the cultures initially receiving 1.0% O2, a transient upregulation of genes related to fatty acid oxidation, peroxisomal biogenesis, response to oxidative stress and pentose phosphate pathway was observed. Additionally, this work analysed the effect of oxygen on transcription of genes belonging to the hexose transporter gene family. Although the specific glucose uptake rate was highest in fully anaerobic conditions, none of the hxt genes showed highest expression in anaerobic conditions. However, the expression of genes encoding the moderately low affinity transporters decreased with the decreasing oxygen level. Thus it was concluded that there is a relative increase in high affinity transport in anaerobic conditions supporting the high uptake rate.

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While environmental variation is an ubiquitous phenomenon in the natural world which has for long been appreciated by the scientific community recent changes in global climatic conditions have begun to raise consciousness about the economical, political and sociological ramifications of global climate change. Climate warming has already resulted in documented changes in ecosystem functioning, with direct repercussions on ecosystem services. While predicting the influence of ecosystem changes on vital ecosystem services can be extremely difficult, knowledge of the organisation of ecological interactions within natural communities can help us better understand climate driven changes in ecosystems. The role of environmental variation as an agent mediating population extinctions is likely to become increasingly important in the future. In previous studies population extinction risk in stochastic environmental conditions has been tied to an interaction between population density dependence and the temporal autocorrelation of environmental fluctuations. When populations interact with each other, forming ecological communities, the response of such species assemblages to environmental stochasticity can depend, e.g., on trophic structure in the food web and the similarity in species-specific responses to environmental conditions. The results presented in this thesis indicate that variation in the correlation structure between species-specific environmental responses (environmental correlation) can have important qualitative and quantitative effects on community persistence and biomass stability in autocorrelated (coloured) environments. In addition, reddened environmental stochasticity and ecological drift processes (such as demographic stochasticity and dispersal limitation) have important implications for patterns in species relative abundances and community dynamics over time and space. Our understanding of patterns in biodiversity at local and global scale can be enhanced by considering the relevance of different drift processes for community organisation and dynamics. Although the results laid out in this thesis are based on mathematical simulation models, they can be valuable in planning effective empirical studies as well as in interpreting existing empirical results. Most of the metrics considered here are directly applicable to empirical data.

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The ongoing rapid fragmentation of tropical forests is a major threat to global biodiversity. This is because many of the tropical forests are so-called biodiversity 'hotspots', areas that host exceptional species richness and concentrations of endemic species. Forest fragmentation has negative ecological and genetic consequences for plant survival. Proposed reasons for plant species' loss in forest fragments are, e.g., abiotic edge effects, altered species interactions, increased genetic drift, and inbreeding depression. To be able to conserve plants in forest fragments, the ecological and genetic processes that threaten the species have to be understood. That is possible only after obtaining adequate information on their biology, including taxonomy, life history, reproduction, and spatial and genetic structure of the populations. In this research, I focused on the African violet (genus Saintpaulia), a little-studied conservation flagship from the Eastern Arc Mountains and Coastal Forests hotspot of Tanzania and Kenya. The main objective of the research was to increase understanding of the life history, ecology and population genetics of Saintpaulia that is needed for the design of appropriate conservation measures. A further aim was to provide population-level insights into the difficult taxonomy of Saintpaulia. Ecological field work was conducted in a relatively little fragmented protected forest in the Amani Nature Reserve in the East Usambara Mountains, in northeastern Tanzania, complemented by population genetic laboratory work and ecological experiments in Helsinki, Finland. All components of the research were conducted with Saintpaulia ionantha ssp. grotei, which forms a taxonomically controversial population complex in the study area. My results suggest that Saintpaulia has good reproductive performance in forests with low disturbance levels in the East Usambara Mountains. Another important finding was that seed production depends on sufficient pollinator service. The availability of pollinators should thus be considered in the in situ management of threatened populations. Dynamic population stage structures were observed suggesting that the studied populations are demographically viable. High mortality of seedlings and juveniles was observed during the dry season but this was compensated by ample recruitment of new seedlings after the rainy season. Reduced tree canopy closure and substrate quality are likely to exacerbate seedling and juvenile mortality, and, therefore, forest fragmentation and disturbance are serious threats to the regeneration of Saintpaulia. Restoration of sufficient shade to enhance seedling establishment is an important conservation measure in populations located in disturbed habitats. Long-term demographic monitoring, which enables the forecasting of a population s future, is also recommended in disturbed habitats. High genetic diversities were observed in the populations, which suggest that they possess the variation that is needed for evolutionary responses in a changing environment. Thus, genetic management of the studied populations does not seem necessary as long as the habitats remain favourable for Saintpaulia. The observed high levels of inbreeding in some of the populations, and the reduced fitness of the inbred progeny compared to the outbred progeny, as revealed by the hand-pollination experiment, indicate that inbreeding and inbreeding depression are potential mechanisms contributing to the extinction of Saintpaulia populations. The relatively weak genetic divergence of the three different morphotypes of Saintpaulia ionantha ssp. grotei lend support to the hypothesis that the populations in the Usambara/lowlands region represent a segregating metapopulation (or metapopulations), where subpopulations are adapting to their particular environments. The partial genetic and phenological integrity, and the distinct trailing habit of the morphotype 'grotei' would, however, justify its placement in a taxonomic rank of its own, perhaps in a subspecific rank.

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Cancer is a leading cause of death worldwide and the total number of cancer cases continues to increase. Many cancers, for example sinonasal cancer and lung cancer, have clear external risk factors and so are potentially preventable. The occurrence of sinonasal cancer is strongly associated with wood dust exposure and the main risk factor for lung cancer is tobacco smoking. Although the molecular mechanisms involved in lung carcinogenesis have been widely studied, very little is known about the molecular changes leading to sinonasal cancer. In this work, mutations in the tumour suppressor TP53 gene in cases of sinonasal cancer and lung cancer and the associations of these mutations with exposure factors were studied. In addition, another important mechanism in many cancers, inflammation, was explored by analyzing the expression of the inflammation related enzyme, COX-2, in sinonasal cancer. The results demonstrate that TP53 mutations are frequent in sinonasal cancer and lung cancer and in both cancers they are associated with exposure. In sinonasal cancer, the occurrence of TP53 mutation significantly increased in relation to long duration and high level of exposure to wood dust. Smoking was not associated with the overall occurrence of the TP53 mutation in sinonasal cancer, but was associated with multiple TP53 mutations. Furthermore, inflammation appears to play a part in sinonasal carcinogenesis as indicated by our results showing that the expression of COX-2 was associated with adenocarcinoma type of tumours, wood dust exposure and non-smoking. In lung cancer, we detected statistically significant associations between TP53 mutations and duration of smoking, gender and histology. We also found that patients with a tumour carrying a G to T transversion, a mutation commonly found in association with tobacco smoking, had a high level of smoking-related bulky DNA adducts in their non-tumorous lung tissue. Altogether, the information on molecular changes in exposure induced cancers adds to the observations from epidemiological studies and helps to understand the role and impact of different etiological factors, which in turn can be beneficial for risk assessment and prevention.

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The Capercaillie (Tetrao urogallus L.) is often used as a focal species for landscape ecological studies: the minimum size for its lekking area is 300 ha, and the annual home range for an individual may cover 30 80 km2. In Finland, Capercaillie populations have decreased by approximately 40 85%, with the declines likely to have started in the 1940s. Although the declines have partly stabilized from the 1990s onwards, it is obvious that the negative population trend was at least partly caused by changes in human land use. The aim of this thesis was to study the connections between human land use and Capercaillie populations in Finland, using several spatial and temporal scales. First, the effect of forest age structure on Capercaillie population trends was studied in 18 forestry board districts in Finland, during 1965 1988. Second, the abundances of Capercaillie and Moose (Alces alces L.) were compared in terms of several land-use variables on a scale of 50 × 50 km grids and in five regions in Finland. Third, the effects of forest cover and fine-grain forest fragmentation on Capercaillie lekking area persistence were studied in three study locations in Finland, on 1000 and 3000 m spatial scales surrounding the leks. The analyses considering lekking areas were performed with two definitions for forest: > 60 and > 152 m3ha 1 of timber volume. The results show that patterns and processes at large spatial scales strongly influence Capercaillie in Finland. In particular, in southwestern and eastern Finland, high forest cover and low human impact were found to be beneficial for this species. Forest cover (> 60 m3ha 1 of timber) surrounding the lekking sites positively affected lekking area persistence only at the larger landscape scale (3000 m radius). The effects of older forest classes were hard to assess due to scarcity of older forests in several study areas. Young and middle-aged forest classes were common in the vicinity of areas with high Capercaillie abundances especially in northern Finland. The increase in the amount of younger forest classes did not provide a good explanation for Capercaillie population decline in 1965 1988. In addition, there was no significant connection between mature forests (> 152 m3ha 1 of timber) and lekking area persistence in Finland. It seems that in present-day Finnish landscapes, area covered with old forest is either too scarce to efficiently explain the abundance of Capercaillie and the persistence of the lekking areas, or the effect of forest age is only important when considering smaller spatial scales than the ones studied in this thesis. In conclusion, larger spatial scales should be considered for assessing the future Capercaillie management. According to the proposed multi-level planning, the first priority should be to secure the large, regional-scale forest cover, and the second priority should be to maintain fine-grained, heterogeneous structure within the separate forest patches. A management unit covering hundreds of hectares, or even tens or hundreds of square kilometers, should be covered, which requires regional-level land-use planning and co-operation between forest owners.

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Although changes in urban forest vegetation have been documented in previous Finnish studies, the reasons for these changes have not been studied explicitly. Especially, the consequences of forest fragmentation, i.e. the fact that forest edges receive more solar radiation, wind and air-borne nutrients than interiors have been ignored. In order to limit the change in urban forest vegetation we need to know why it occurs. Therefore, the effects of edges and recreational use of urban forests on vegetation were investigated together in this thesis to reveal the relative strengths of these effects and to provide recommendations for forest management. Data were collected in the greater Helsinki area (in the cities of Helsinki, Vantaa and Espoo, and in the municipalities of Sipoo and Tuusula) and in the Lahti region (in the city of Lahti and in the municipality of Hollola) by means of systematic and randomized vegetation and soil sampling and tree measurements. Sample plots were placed from the forest edges to the interiors to investigate the effects of forest edges, and on paths of different levels of wear and off these paths to investigate the effects of trampling. The natural vegetation of mesic and sub-xeric forest site types studied was sensitive both to the effects of the edge and to trampling. The abundances of dwarf shrubs and bryophytes decreased, while light- and nitrogen-demanding herbs and grasses - and especially Sorbus aucuparia – were favoured at the edges and next to the paths. Results indicated that typical forest site types at the edges are changing toward more nitrophilic vegetation communities. Covers of the most abundant forest species decreased considerably – even tens of percentages – from interiors to the edges indicating strong edge effects. These effects penetrated at least up to 50 m from the forest edges into the interiors, especially at south to west facing open edges. The effects of trampling were pronounced on paths and even low levels of trampling decreased the abundances of certain species considerably. The effects of trampling extended up to 8 m from path edges. Results showed that the fragmentation of urban forest remnants into small and narrow patches should be avoided in order to maintain natural forest understorey vegetation in the urban setting. Thus, urban forest fragments left within urban development should be at least 3 ha in size, and as circular as possible. Where the preservation of representative original forest interior vegetation is a management aim, closed edges with conifers can act as an effective barrier against solar radiation, wind and urban load, thereby restricting the effects of the edge. Tree volume at the edge should be at least 225-250 m3 ha-1 and the proportion of conifers (especially spruce) 80% or more of the tree species composition. Closed, spruce-dominated edges may also prevent the excessive growth of S. aucuparia saplings at urban forest edges. In addition, closed edges may guide people’s movements to the maintained paths, thus preventing the spontaneous creation of dense path networks. In urban areas the effects of edges and trampling on biodiversity may be considerable, and are important to consider when the aim of management is to prevent the development of homogeneous herb-grass dominated vegetation communities, as was observed at the investigated edges.