44 resultados para Additive combinatorics


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Tässä diplomityössä tutkittiin kalvosuodatuksen esikäsittelymenetelmiä ja kalvonpesua. Työn kirjallisuusosassa käsitellään vuon alenemiseen vaikuttavia tekijöitä, esikäsittelymenetelmiä ja kalvonpesua. Kokeellisessa osassa tutkittiin kemiallisten esikäsittelyjen vaikutusta vuon alenemiseen paperitehtaan happaman kiertoveden kirkkaan suodoksen kalvosuodatuksessa. Esikäsittelykemikaalit olivat ympäristöystävällisiä ja paperinvalmistusprosessiin soveltuvia. Lisäksi tutkittiin kalvonpesuaineiden pesutehokkuuksia. Tutkitut esikäsittelyaineet olivat mikrokiteinen kitosaani, karboksimetyyliselluloosa, selluloosa- ja puukuitu sekä kaupallinen antiskalantti. Pesuaineista tutkittiin kolmea kaupallista kalvonpesuainetta, yhtä kalvopesun tehostusainetta sekä peretikkahappoa. Kokeet tehtiin kahdella laboratoriomittakaavaisella kalvosuodattimella. Kalvoina käytettiin kahta nanosuodatus- ja yhtä ultrasuodatuskalvoa. Vuon alenemista tutkittiin suodatuksen aikaisena alenemisena ja vesivuohon verrattavana alenemisena. Esikäsittelyjen vaikutusta erotustehokkuuteen tutkittiin ioni-, johtokyky-, orgaanisen hiilen kokonaispitoisuus-, sokeri-, sameus- ja ligniinireduktioilla. Lisäksi määritettiin kalvon likaantuminen suodatuksen aikana vesivuon määrityksillä ennen ja jälkeen suodatuksen. Pesutehokkuus määritettiin vesivuon määrityksillä suodatuksen jälkeen ja pesun jälkeen. Kitosaani- ja karboksimetyyliselluloosakäsittelyillä oli vuon alenemista estävä vaikutus hydrofiilisellä nanosuodatuskalvolla suodatettaessa. Kitosaanikäsittelyn 5 g/dm3:n ja karboksimetyyliselluloosakäsittelyn 2 g/ dm3:n annostuksella vuot alentuivat suodatuksen aikana 8 %-yksikköä vähemmän kuin ilman esikäsittelyä. Puukuitukäsittely stabiloi 0,1 g/dm3:n annostuksella saman kalvon vuota, kun kiintoainetta ei poistettu syötöstä. Hydrofobisen nanosuodatuskalvon vuon alenemista ehkäisivät puu- ja selluloosakuitukäsittelyt sekä karboksimetyyliselluloosakäsittely. Karboksimetyyliselluloosakäsittely vähensi vuon alenemista 25 %-yksikköä ja puukuitukäsittely 13 %-yksikköä. Hydrofiilisellä ultrasuodatuskalvolla vuon aleneminen oli pientä ilman esikäsittelyä. Reduktioihin esikäsittelyt vaikuttivat parhaiten ultrasuodatuskalvolla. Kitosaanikäsittely nosti 1 g/dm3:n annostuksella alumiinireduktion 50 %:sta 96 %:iin ja 5 g/dm3:n annostuksella rautareduktion 30 %:sta 55 %:iin. Karboksyylimetyyliselluloosakäsittelyt vaikuttivat parantavasti mangaanin, magnesiumin, raudan ja kalsiumin reduktioihin. Optimi karboksyylimetyyliselluloosa-annostus oli 2 g/dm3. Merkittävin reduktion nousu oli kalsiumilla, jonka reduktio nousi esikäsittelyllä 4 %:sta 57 %:iin. Reduktiota nostava mekanismi oli kalvon pinnalle muodostuva sekundaarikerros. Pesuaineista tehokkain oli entsyymiä sisältävä kalvonpesuaine. Suurin vaikutus sillä oli hydrofobisen nanosuodatuskalvon pesussa. Optimiannostuksella (0,5 %) kalvon vesivuo pesun jälkeen oli 114 % pesua edeltäneestä vesivuosta. Muut kaupalliset pesuaneet oli tehokkaita hydrofiilisille kalvoille. Peretikkahappo oli yksittäisenä pesuaineena heikkotehoinen.

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Substances emitted into the atmosphere by human activities in urban and industrial areas cause environmental problems such as air quality degradation, respiratory diseases, climate change, global warming, and stratospheric ozone depletion. Volatile organic compounds (VOCs) are major air pollutants, emitted largely by industry, transportation and households. Many VOCs are toxic, and some are considered to be carcinogenic, mutagenic, or teratogenic. A wide spectrum of VOCs is readily oxidized photocatalytically. Photocatalytic oxidation (PCO) over titanium dioxide may present a potential alternative to air treatment strategies currently in use, such as adsorption and thermal treatment, due to its advantageous activity under ambient conditions, although higher but still mild temperatures may also be applied. The objective of the present research was to disclose routes of chemical reactions, estimate the kinetics and the sensitivity of gas-phase PCO to reaction conditions in respect of air pollutants containing heteroatoms in their molecules. Deactivation of the photocatalyst and restoration of its activity was also taken under consideration to assess the practical possibility of the application of PCO to the treatment of air polluted with VOCs. UV-irradiated titanium dioxide was selected as a photocatalyst for its chemical inertness, non-toxic character and low cost. In the present work Degussa P25 TiO2 photocatalyst was mostly used. In transient studies platinized TiO2 was also studied. The experimental research into PCO of following VOCs was undertaken: - methyl tert-butyl ether (MTBE) as the basic oxygenated motor fuel additive and, thus, a major non-biodegradable pollutant of groundwater; - tert-butyl alcohol (TBA) as the primary product of MTBE hydrolysis and PCO; - ethyl mercaptan (ethanethiol) as one of the reduced sulphur pungent air pollutants in the pulp-and-paper industry; - methylamine (MA) and dimethylamine (DMA) as the amino compounds often emitted by various industries. The PCO of VOCs was studied using a continuous-flow mode. The PCO of MTBE and TBA was also studied by transient mode, in which carbon dioxide, water, and acetone were identified as the main gas-phase products. The volatile products of thermal catalytic oxidation (TCO) of MTBE included 2-methyl-1-propene (2-MP), carbon monoxide, carbon dioxide and water; TBA decomposed to 2-MP and water. Continuous PCO of 4 TBA proceeded faster in humid air than dry air. MTBE oxidation, however, was less sensitive to humidity. The TiO2 catalyst was stable during continuous PCO of MTBE and TBA above 373 K, but gradually lost activity below 373 K; the catalyst could be regenerated by UV irradiation in the absence of gas-phase VOCs. Sulphur dioxide, carbon monoxide, carbon dioxide and water were identified as ultimate products of PCO of ethanethiol. Acetic acid was identified as a photocatalytic oxidation by-product. The limits of ethanethiol concentration and temperature, at which the reactor performance was stable for indefinite time, were established. The apparent reaction kinetics appeared to be independent of the reaction temperature within the studied limits, 373 to 453 K. The catalyst was completely and irreversibly deactivated with ethanethiol TCO. Volatile PCO products of MA included ammonia, nitrogen dioxide, nitrous oxide, carbon dioxide and water. Formamide was observed among DMA PCO products together with others similar to the ones of MA. TCO for both substances resulted in the formation of ammonia, hydrogen cyanide, carbon monoxide, carbon dioxide and water. No deactivation of the photocatalyst during the multiple long-run experiments was observed at the concentrations and temperatures used in the study. PCO of MA was also studied in the aqueous phase. Maximum efficiency was achieved in an alkaline media, where MA exhibited high fugitivity. Two mechanisms of aqueous PCO – decomposition to formate and ammonia, and oxidation of organic nitrogen directly to nitrite - lead ultimately to carbon dioxide, water, ammonia and nitrate: formate and nitrite were observed as intermediates. A part of the ammonia formed in the reaction was oxidized to nitrite and nitrate. This finding helped in better understanding of the gasphase PCO pathways. The PCO kinetic data for VOCs fitted well to the monomolecular Langmuir- Hinshelwood (L-H) model, whereas TCO kinetic behaviour matched the first order process for volatile amines and the L-H model for others. It should be noted that both LH and the first order equations were only the data fit, not the real description of the reaction kinetics. The dependence of the kinetic constants on temperature was established in the form of an Arrhenius equation.

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Tietovarastoissa moniulotteinen tietomalli on tehokkain tapa esittää tietoa päätöksentekijöille. Sen toimivuus on hyväksi havaittu monissa eri liiketoimintaympäristöissä. Tehdasympäristöissä on tuhansia mittalaitteita, joista jokainen mittaa uniikkia valmistusprosessiin liittyvää piirrettä. Tässä työssä kehitettiin tietovarasto tehdasmittausten varastointiin käyttäen moniulotteista tietomallia. Havaittiin, että moniulotteisella mallilla tehdasmittaukset voidaan tallentaa joustavalla tavalla ja esittää käyttäjälle mielekkäässä muodossa. Moniulotteinen malli antaa myös erinomaiset keinot tiedon ryhmittelyyn ja vertailuun. Sillä ei kuitenkaan saada vastaavanlaisia hyötyjä kuin klassisissa kaupanalan tietovarastointi esimerkeissä, koska eri mittaukset ovat keskenään hyvin erilaisia. Vaikka mittaukset eivät olekaan aina vertailtavissa tai summattavissa keskenään, saadaan ne moniulotteisella mallilla tallennettua ja luokiteltua loogisesti siten, että käyttäjän on helppo löytää tarvitsemansa tieto. Lisäksi yleisesti tunnettu ja paljon käytetty tietovaraston suunnittelumalli takaa sen, että markkinoilta on saatavissa työkaluja tietovaraston käyttöön. Tietokannan toteutus tehtiin vapaasti levitettävän MySQLtiedonhallintajärjestelmän avulla. Sitä ei ole suunniteltu pääasiassa tietovarastokäyttöön, mutta halpa lisenssi ja hyvä skaalautuvuus tekevät siitä mielenkiintoisen vaihtoehdon. Sitä onkin käytetty luultua enemmän tietovarastoinnissa ja myös monien nimekkäiden organisaatioiden toimesta. Myös tässä työssä todettiin, että MySQL tarjoaa riittävät välineet tietovaraston kehittämiseen.

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Diplomityön tarkoituksena oli tutkia ja kehittää käyttökohde kaivosteollisuudessa syntyvälle märälle kipsisivuvirralle, joka sisältää metalliepäpuhtauksina alumiinia, rautaa ja mangaania ja jonka määrä on noin 1 000 000 t/a. Kirjallisuuden pohjalta tutkittiin aluksi mahdollisuutta hyödyntää kipsiaines asfaltti- ja sementtiteollisuuden raaka-aineena. Sementin joukkoon lisätään tavallisesti noin 5 p-% kipsiä, mutta harvinaisimpiin sementtilaatuihin sitä voidaan lisätä jopa 30 p-%. Tästä huolimatta vain pieni osa tutkimuksen kohteessa syntyvästä kipsisivuvirrasta voitaisiin hyödyntää tässä sovelluksessa. Lisäksi kipsisivuvirran sisältämät epäpuhtaudet täytyisi poistaa tai saattaa inaktiiviseen muotoon. Myöskään sen kosteuspitoisuus ei saisi olla suuri. Näin ollen tämän kipsisivuvirran hyödyntäminen asfaltti- ja sementtiteollisuuden lisäaineena ei ole mahdollista Seuraavaksi harkittiin kipsin kierrättämistä, jolloin yhtenä vaihtoehtona oli hajottaa kipsi termisesti rikkioksideiksi ja valmistaa niistä rikkihappoa. Taloudellisista syistä hajoamistuotteen on oltava rikkitrioksidia, josta voitaisiin veteen imeyttämällä valmistaa rikkihappoa. Kipsin hajottaminen termovaa´alla osoitti, että kipsi vaatii noin 1400 ºC:n lämpötilan ja haihtuvat komponentit ovat H2O, SO ja SO2, muttei SO3. Alempien oksidien muuttaminen rikkihapoksi vaatisi katalyyttisen hapetuksen, mikä olisi käytännössä liian kallista. Toisena vaihtoehtona kipsin kierrättämiseksi tutkittiin sen biologista pelkistämistä rikkivedyksi ja kalsiumhydroksidilietteeksi. Laboratoriossa Ca(OH)2-lietteestä valmistettiin hiilidioksidin avulla kalsiumkarbonaattia, jolloin päästiin 90 %:n kalsiumhydroksidin konversiossa. Lisäksi alumiinihydroksidi saatiin erotettua kipsilietteestä kokeellisesti hydrosyklonin avulla. Diplomityössä päädyttiin siihen, että sulfaatin biologinen pelkistäminen ja alumiinihydroksidin mekaaninen erotus jatkuvatoimisesti on varteenotettava vaihtoehto kipsisivuvirran hyödyntämiseksi.

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Diplomityön tarkoituksena on analysoida ja kehittää erään puunjalostuskonsernin voiteluhuoltoa. Tutkimuksen kirjallisessa osassa on selvitetty voitelun perusteet, voiteluaineet sekä voiteluhuoltoon liittyviä yleisiä käsitteitä ja termejä. Työssä on selvitetty ohjeita voiteluaineiden valintaan ja voiteluöljyjen kunnonvalvontamenetelmiin sekä selvitetty voiteluaineiden puhtauden merkitystä. Lisäksi on esitetty katselmus eri voitelumekanismista. Näiden sovellusesimerkkinä on laskettu paperikoneen kuivaussylinterin laakerin voitelukalvon ominaispaksuus. Osan lopussa on tutkittu voiteluaineiden varastoinnin ja käytettyjen voiteluaineiden jatkokäsittelyn merkitystä ympäristöasiat huomioiden. Soveltavassa osassa on edellistä hyödyntäen analysoitu puunjalostuskonsernin yksitoista eri paikkakuntaa voiteluhuollon toimivuuden kannalta. Tämä tilastollinen tieto on kerätty sekä kyselykaavakkeen avulla että haastattelemalla jokaisen paikkakunnan voiteluhuollon asiantuntijoita. Lopputuloksena on saatu voiteluhuollon kehityskohteet ja SWOT-analyysit paikkakunnittain sekä yhteenveto voiteluhuollon eri toimintojen parhaimmista käytännöistä. Lisäksi analyysin perusteella laadittiin konsernin voiteluhuollon kehityssuunnitelma.

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Tämän työn tavoitteena oli löytää keinot taivekartongin riittävän z-suuntaisen lujuuden saavuttamiseksi tilanteessa, jossa runkokerrokseen annosteltavan hylyn määrää joudutaan pysyvästi vähentämään. Työn kirjallisuusosassa selvitettiin taivekartongin tärkeimmät ominaisuudet, joista tarkemmin tarkasteltiin palstautumislujuutta ja siihen vaikuttavia tekijöitä. Lisäksi käytiin läpi palstautumislujuuden mittausmenetelmät. Merkittävimpiä teoriaosassa käsiteltyjä palstautumislujuuteen vaikuttavia tekijöitä olivat massojen käsittely ja annostelu, kuivalujalisäaineiden käyttö sekä rainanmuodostus. Hylyn annosteluosuuden pienentäminen vähensi taivekartongin paksuussuuntaista lujuutta ja runkomassan vedenpoistovastusta, mutta samanaikaisesti lisääntyivät kartongin paksuus ja taivutusjäykkyys. Hylyn vähäisemmän käytön seurauksena menetettyä lujuutta ei pystytty palauttamaan hylyn jauhatuksen määrää lisäämällä, eikä kartonkikoneen runkoviiraosan vedenpoistoon vaikuttamalla. Kun hylyn annosteluosuus laskettiin 20 %:in, saavutettiin runkokerroksen riittävä lujuus ainoastaan runkomassan pääkomponenttina käytettävän hiokemassaseoksen jauhatusastetta nostamalla tai korvaamalla pieni osa hiokkeesta hyvin hienoksi jauhetulla mäntysellulla. Hiokkeen freeness oli laskettava tasolta 300 ml CSF tasolle 250 ml CSF. Vastaavasti mäntysellu oli jauhettava hyvin pitkälle (°SR 74) tai annosteluosuuden oli oltava vähintään 2 %, jolloin jauhatusaste °SR 49 oli riittävä. Vähäisemmällä hylyn käytöllä saavutettu etu vedenpoistossa saatettaisiin menettää näiden toimenpiteiden vaikutuksesta.

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Fine powders of minerals are used commonly in the paper and paint industry, and for ceramics. Research for utilizing of different waste materials in these applications is environmentally important. In this work, the ultrafine grinding of two waste gypsum materials, namely FGD (Flue Gas Desulphurisation) gypsum and phosphogypsum from a phosphoric acid plant, with the attrition bead mill and with the jet mill has been studied. The ' objective of this research was to test the suitability of the attrition bead mill and of the jet mill to produce gypsum powders with a particle size of a few microns. The grinding conditions were optimised by studying the influences of different operational grinding parameters on the grinding rate and on the energy consumption of the process in order to achieve a product fineness such as that required in the paper industry with as low energy consumption as possible. Based on experimental results, the most influential parameters in the attrition grinding were found to be the bead size, the stirrer type, and the stirring speed. The best conditions, based on the product fineness and specific energy consumption of grinding, for the attrition grinding process is to grind the material with small grinding beads and a high rotational speed of the stirrer. Also, by using some suitable grinding additive, a finer product is achieved with a lower energy consumption. In jet mill grinding the most influential parameters were the feed rate, the volumetric flow rate of the grinding air, and the height of the internal classification tube. The optimised condition for the jet is to grind with a small feed rate and with a large rate of volumetric flow rate of grinding air when the inside tube is low. The finer product with a larger rate of production was achieved with the attrition bead mill than with the jet mill, thus the attrition grinding is better for the ultrafine grinding of gypsum than the jet grinding. Finally the suitability of the population balance model for simulation of grinding processes has been studied with different S , B , and C functions. A new S function for the modelling of an attrition mill and a new C function for the modelling of a jet mill were developed. The suitability of the selected models with the developed grinding functions was tested by curve fitting the particle size distributions of the grinding products and then comparing the fitted size distributions to the measured particle sizes. According to the simulation results, the models are suitable for the estimation and simulation of the studied grinding processes.

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Gonadal somatic cell and adrenocortical endocrine tumors are rare. The incidence of adrenocortical carcinomas is only 1-2/1000000 a year. However, they are aggressive, especially in adulthood and currently surgery is the only curative treatment. Cytotoxic agents are in use in advanced cancers, but side effects and multidrug resistance are often problems. Thus there is a need for novel curative treatment methods. In contrast, ovarian granulosa cell tumors and testicular Leydig cell tumors are usually benign, especially at a younger age. The aim of the present thesis was to study a novel targeted treatment method through luteinizing hormone/chorionic gonadotropin receptor (LHCGR) in a transgenic mouse tumor model. The cytotoxic agent was lytic peptide Hecate-CGbeta conjugate where 23 amino acid Hecate, a synthetic form of honeybee venom melittin, was conjugated to 15 amino acid fragment of human chorionic gonadotropin β subunit. Lytic peptides are known to act only on negatively charged cells, such as bacteria and cancer cells and hereby, due to hCGbeta fragment, the conjugate is able to bind directly to LHCGR bearing cancer cells, saving the healthy ones. The experiments were carried out in inhibin-alpha-Simian Virus 40-T-antigen transgenic mice that are known to express LHCGR-bearing gonadal tumors, namely Leydig and granulosa cell tumors by 100% penetrance. If the mice are gonadectomized prepubertally they form adrenocortical tumors instead. Transgenic and wild type mice were treated for three consecutive weeks with control vehicle, Hecate or Hecate-CGbeta conjugate. GnRH antagonist or estradiol was given to a group of mice with or without Hecate-CGbeta conjugate to analyze the additive role of gonadotropin blockage in adrenocortical tumor treatment efficacy. Hecate-CGbeta conjugate was able to diminish the gonadal and adrenal tumor size effectively in males. No treatment related side effects were found. Gonadotropin blockage through GnRH antagonist was the best treatment in female adrenal tumors. The mode of cell death by Hecate-CGbeta conjugate was proven to be through necrosis. LHCGR and GATA-4 were co-expressed in tumors, where the treatment down-regulated their expression simultaneously, suggesting their possible use as tumor markers. In conclusion, the present thesis showed that Hecate-CGbeta conjugate targets its action selectively through LHCGR and selectively kills the LHCGR bearing tumor cells. It works both in gonadal somatic and in ectopic LHCGR bearing adrenal tumors. These results establish a more general principle that receptors expressed ectopically in malignant cells can be exploited in targeted cytotoxic therapies without affecting the normal healthy cells.

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Saostettua karbonaattia voidaan käyttää useiden eri teollisuuksien tuotteissa. Pääosin saostettua kalsiumkarbonaattia kuitenkin käytetään paperin, maalien, muovien sekä elintarviketuotteiden täyteaineena. Koska monet käyttökohteet vaativat saostetulta kalsiumkarbonaatilta tiettyjä puhtausvaatimuksia, sen koostumuksen tutkiminen on suuren kiinnostuksen kohteena. Työn perimmäisenä tarkoituksena on ollut määrittää saostetun kalsiumkarbonaatin kemiallinen koostumus ja selvittää, vaikuttavatko materiaalin kemiallisfysikaalinen modifiointi sen ominaisuuksiin. Kirjallisuusosassa käsitellään yleisesti kalsiumkarbonaattimateriaaleja, saostetun kalsiumkarbonaatin valmistusmenetelmiä ja vastaavanlaisen materiaalin esikäsittelymenetelmiä. Lisäksi tarkastellaan erilaisia analyysimenetelmiä, joita voidaan käyttää kiinteiden epäorgaanisten tai mineraalinäytteiden kemiallisen koostumuksen sekä fysikaalisten ja kemiallisten reaktioiden määrittämiseen. Kokeellisessa osassa tutkittiin käsittelemättömiä saostettuja kalsiumkarbonaattinäytteiden ominaisuuksia ja kemiallista koostumusta erilaisilla alkuaine-, ioni-/spesies- sekä pyrolyysimittauksilla. Näytteitä modifioitiin lämmityksen ja jauhatuksen avulla. Modifioinnin vaikutusta näytteiden kemiallisiin koostumuksiin tutkittiin vertailemalla tuloksia käsittelemättömien näytteiden antamiin tuloksiin. Tutkimus osoitti, että näytteiden lämpökäsittelyllä ei ollut lähes ollenkaan vaikutusta näytteiden kemialliseen koostumukseen. Toisin osoitti näytteiden jauhatus, joka laski ammoniumin pitoisuutta näytteissä. Laitetekniikkaa käytettäessä kapillaarielektroforeesi, ionikromatografi, ICP-AES ja SEM (FTIR) antoivat luotettavinta tietoa näytteiden kemiallisista koostumuksista. Näytteiden fysikaalisia ja kemiallisia reaktioita voitiin havainnollistaa parhaiten käyttäen STA-QMS -laitetta.

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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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This Master’s thesis examines the feasibility of eBusiness in developing countries by looking at the current mobile banking solutions. The research involved reviewing literature that was relevant to the research questions. It was discovered that the Wizzit and M-PESA are the current solutions to mobile banking. Furthermore, it was found out that the Wizzit and M-PESA were either transformational or additive. Additive mobile banking is the use of mobile phones as a channel to provide services to existing customers within financial institutions. Transformational mobile banking extends financial services to the unbanked. The results of the thesis are M-PESA works with only Safaricom while on the other hand Wizzit has compatibility with any mobile operator. The other result is that both M-PESA and Wizzit are transformational mobile banking technologies at the sametime Wizzit is an Additive mobile banking technology. Wizzit can provide financial services to both the unbanked and existing bank customers. It can be said the merits of Wizzit outweigh those of M-PESA which makes Wizzit better.

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Decreasing bone mass during aging predisposes to fractures and it is estimated that every second woman and one in five men will suffer osteoporotic fractures during their lifetime. Bone is an adaptive tissue undergoing continuous remodeling in response to physical and metabolic stimuli. Bone mass decreases through a net negative balance in the bone remodeling process of bone, in which the new bone incompletely replaces the resorbed bone mass. Bone resorption is carried out by the osteoclasts; the bone mineral is solubilized by acidification and the organic matrix is subsequently degraded by proteases. Several classes of drugs are available for prevention of osteoporotic fractures. They act by different mechanisms to increase bone mass, and some of them act mainly as antiresorptives by inhibition of osteoclast formation or their function. Optimally, a drug should act selectively on a specific process, since other processes affected usually result in adverse effects. The purpose of this study was to evaluate whether the osteoclastic vacuolar adenosine trisphosphatases (V-ATPase), which drives the solubilization of bone mineral, can be selectively inhibited despite its ubiquitous cellular functions. The V-ATPase is a multimeric protein composed of 13 subunits of which six possesses two or more isoforms. Selectivity for the osteoclastic V-ATPase could be provided if it has some structural uniqueness, such as a unique isoform combination. The a3 isoform of the 116kDa subunit is inevitable for bone resorption; however, it is also present in, and mainly limited to, the lysosomes of other cells. No evidence of a structural uniqueness of the osteoclastic V-ATPase compared to the lysosomal V-ATPase was found, although this can not yet be excluded. Thus, an inhibitor selective for the a3 isoform would target the lysosomal V-ATPase as well. However, the results suggest that selectivity for bone resorption over lysosomal function can be obtained by two other mechanisms, suggesting that isoform a3 is a valid target. The first is differential compensation; bone resorption depends on the high level of a3 expression, and is not compensated for by other isoforms, while the lower level of a3 in lysosomes of other cells may be partly compensated for. The second mechanism is because the bone resorption process itself is fundamentally different from lysosomal acidification because of the chemistry of bone dissolution and the anatomy of the resorbing osteoclast. By this mechanism, full inhibition of bone resorption is obtained with more than tenfold lower inhibitor concentration than those needed to fully inhibit lysosomal acidification. The two mechanisms are additive. Based on the results, we suggest that bone resorption can be selectively inhibited if VATPase inhibitors that are sufficiently selective for the a3 isoform over the other isoforms are developed.

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The study examines the signalling of text organisation in research articles (RA) in French. The work concentrates on a particular type of organisation provided by text sequences, i.e. structures organising text to items of which at least some are signalled by markers of addition or order: First… 0… The third point… In addition… / Premièrement… 0… Le troisième point… De plus… By indicating the way the text is organised, these structures guide the reader in the reading process so that he doesn’t need to interpret the text structure himself. The aim of the work is to study factors affecting the marking of text sequences. Why is their structure sometimes signalled explicitly by markers such as secondly, whereas in other places such markers are not used? The corpus is manually XML-annotated and consists of 90 RAs (~800 000 words) in French from the fields of linguistics, education and history. The analysis highlights several factors affecting the marking of text sequences. First, exact markers (such as fist ) seem to be more frequent in sequences where all the items are explicitly signalled by a marker, whereas additive markers (such as moreover) are used in sequences with both explicitly signalled and unmarked items. The marking of explicitly signalled sequences seems thus to be precise and even repetitive, whereas the signalling of sequences with unmarked items is altogether more vague. Second, the marking of text sequences seems to depend on the length of the text. The longer the text segment, the more vague the marking. Additive markers and unmarked items are more frequent in longer sequences possibly covering several pages, whereas shorter sequences are often signalled explicitly by exact markers. Also the marker types vary according to the sequence length. Anaphoric expressions, such as first, are fairly close to their referents and are used in short sequences, connectors, such as secondly, are frequently used in sequences of intermediate length, whereas the longest sequences are often signalled by constructions composed of an ordinal and a noun acting as a subject of the sentence: The first item is… Finally, the marking of text organisation depends also on the discipline the RA belongs to. In linguistics, the marking is fairly frequent and precise; exact markers such as second are the most used, and structures with unmarked items are less common. Similarly, the marking is fairly frequent in education. In this field, however, it is also less precise than in linguistics, with frequent unmarked items and additive markers. History, on the other hand, is characterised by less frequent marking. In addition, when used, the marking in this field is also less precise and less explicit.

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Laserpinnoitus on additiivinen prosessi, jossa lasertehon avulla sulatetaan pinnoitusainetta pinnoitettavan kappaleen pintaan. Laserpinnoituksella on mahdollista aikaansaada tiivis sekä kova, kulutusta ja korroosiota kestävä pinnoite kappaleen pintaan. Tässä työssä kohteena oli potkurilaitteen ohjausputken laserpinnoitus. Kyseisessä kohteessa pinnoitteelta vaaditaan hyvää korroosion- ja kulumisen kestoa. Työn tavoitteena oli lisätä tietoisuutta laserpinnoitusprosessista ja siinä vaikuttavista tekijöistä. Myös materiaaliominaisuuksien vaikutuksia sekä pinnoitus- että pinnoitettavien aineiden osalta selvitettiin. Työhön sisältyi myös kokeellinen osuus, jossa tavoitteena oli löytää kustannustehokkain pinnoiteaine tutkittuun kohteeseen. Kokeissa ohjausputki- sekä levyaihioon tehtiin koepinnoituksia. Kokeiden ja edelleen materiaalitutkimuksien avulla tutkittiin neljää eri pinnoitusainetta, jotka olivat Stellitti 21, Inconel 625, AISI 316L ja AISI 431. Kovuus- ja taivutuskokeiden perusteella kyseisistä aineista vain Stelliitti 21 täytti ohjausputken pinnoitteelle asetetut vaatimukset. Näin ollen Stelliitti 21 valikoitui kustannustehokkaimmaksi pinnoitusaineeksi ohjausputkien laserpinnoitukseen.

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The role of genetic factors in the pathogenesis of Alzheimer’s disease (AD) is not completely understood. In order to improve this understanding, the cerebral glucose metabolism of seven monozygotic and nine dizygotic twin pairs discordant for AD was compared to that of 13 unrelated controls using positron emission tomography (PET). Traditional region of interest analysis revealed no differences between the non-demented dizygotic co-twins and controls. In contrast, in voxel-level and automated region of interest analyses, the non-demented monozygotic co-twins displayed a lower metabolic rate in temporal and parietal cortices as well as in subcortical grey matter structures when compared to controls. Again, no reductions were seen in the non-demented dizygotic co-twins. The reductions seen in the non-demented monozygotic co-twins may indicate a higher genetically mediated risk of AD or genetically mediated hypometabolism possibly rendering them more vulnerable to AD pathogenesis. With no disease modifying treatment available for AD, prevention of dementia is of the utmost importance. A total of 2 165 at least 65 years old twins of the Finnish Twin Cohort with questionnaire data from 1981 participated in a validated telephone interview assessing cognitive function between 1999 and 2007. Those subjects reporting heavy alcohol drinking in 1981 had an elevated cognitive impairment risk over 20 years later compared to light drinkers. In addition, binge drinking was associated with an increased risk even when total alcohol consumption was controlled for, suggesting that binge drinking is an independent risk factor for cognitive impairment. When compared to light drinkers, also non-drinkers had an increased risk of cognitive impairment. Midlife hypertension, obesity and low leisure time physical activity but not hypercholesterolemia were significant risk factors for cognitive impairment. The accumulation of risk factors increased cognitive impairment risk in an additive manner. A previously postulated dementia risk score based on midlife demographic and cardiovascular factors was validated. The risk score was found to well predict cognitive impairment risk, and cognitive impairment risk increased significantly as the score became higher. However, the risk score is not accurate enough for use in the clinic without further testing.