Atk-avusteinen tilintarkastus

Tutkimuksen päätavoitteena oli atk-avusteisen tilintarkastuksen käytön tutkiminen. Tutkimus jakaantuu teoreettiseen ja empiiriseen osaan. Teoriaosuudessa käydään läpi tilintarkastusprosessia ja esitellään tietokoneavusteisen tilintarkastuksen työvälineitä sekä arvioidaan kirjallisuuden ja muun lähdeaineiston perusteella atk:n tuottamia hyötyjä ja aiheuttamia riskejä. Empiriaosuudessa tutkittiin tilintarkastajille suunnatun kyselytutkimuksen avulla miten laajaa atk:n hyväksikäyttö on tilintarkastusmaailmassa ja miten tilintarkastajat itse näkevät sen tuomat hyödyt ja haitat sekä atk-avusteisen tilintarkastuksen kehittymisen lähitulevaisuudessa. Tutkimustuloksia verrataan aikaisemmin samasta aihepiiristä tehtyjen tutkimusten tuloksiin. Tutkimustuloksia verrattaessa käy ilmi, että tietokoneen käyttö ja hyödyntäminen tilintarkastustyössä on selvästi lisääntynyt. On huomattava, että atk:n mukaantulo tilintarkastustoimintaan tuo mukanaan ongelmia, jotka tulee tiedostaa, mutta atk:n tuottamien lisäetujen määrä on niin huomattava, että tulevaisuudessa tehokas tilintarkastustyö ei onnistu ilman atk-avusteisia menetelmiä.

Sähköisen taloushallinnon kehityksen vaikutukset tilintarkastukseen ammattilehtikirjoittelussa vuosina 2003-2013

Tutkielman tavoitteena on tutkia, miten sähköisen taloushallinnon kehitys on vaikuttanut tilintarkastukseen ja miten se näkyy ammattilehtien kirjoittelussa vuosina 2003-2013. Alatavoitteina tutkitaan, mitä sähköisen taloushallinnon kehityksen tuomia hyötyjä ja haasteita on havaittu tarkastellussa suomalaisessa sekä kansainvälisessä ammattilehtikirjoittelussa tilintarkastuksen näkökulmasta. Kyseessä on laadullinen tutkimus ja tutkimusmetodologiana käytetään sisällönanalyysia. Tietokoneavusteisten tilintarkastuksen tekniikoiden kehityksen seurauksena tekniikoita voidaan kehittää kohti jatkuvaa tilintarkastusta. Kannettavien tietokoneiden ja pilvipalveluiden seurauksena tilintarkastuksesta on tullut enemmän ajasta ja paikasta riippumatonta. XBRL:n avulla tietojen vertailtavuus, luotettavuus ja tarkkuus ovat parantuneet. Haasteina voidaan nähdä tilintarkastajien IT-taitojen kehittämisen tarve sekä asiakkaan ja tilintarkastusyhteisön tietojärjestelmien yhteensopivuus. Hyvätkin ohjelmistot voivat altistaa väärinkäytöksille, jolloin tarvitaan uusia innovatiivisia tekniikoita väärinkäytösten havaitsemiseen. Tutkielman empiirisen osion luotettavuus perustuu ammattilehtien artikkeleiden kirjoittajien näkökulmiin. Tilintarkastusalan kehittyminen tulevaisuudessa on kiinni kehittyvän tekniikan lisäksi asenteista.

Kunnallisen jätevedenkäsittelyn tehostaminen membraanitekniikan avulla – esimerkkinä Savitaipaleen jätevedenpuhdistamo

Työssä tutkittiin mahdollisuutta tehostaa kunnallista jätevedenpuhdistusta membraanitekniikkaa käyttäen. Teoriaosassa perehdyttiin kunnallisen jäteveden omi-naisuuksiin ja perinteiseen puhdistusprosessiin. Tämän lisäksi membraanien yleisiä ominaisuuksia, membraanityyppien kykyä erottaa jäteveden sisältämiä yhdisteitä sekä erilaisia mahdollisuuksia membraanisuodatukselle perinteisen jäteve-denpuhdistusprosessin yhteydessä käytiin läpi. Kokeellisessa osassa keskityttiin Savitaipaleen puhdistamon puhdistetun jäteveden laadun parantamiseen membraanisuodatukseen perustuvalla jälkikäsittely-yksiköllä eli tertiäärisuodatuksella. Erilaisia paineavusteisia membraanitekniikoita (MF, UF, NF ja RO) tutkittiin jäteveden puhdistamiseksi ja erotustehokkuuden vertailemiseksi. Tavoitteena oli löytää tehokas ja käytännössä toimiva tapa poistaa fosforia ja typpeä puhdistetusta jätevedestä. Tasomaisilla membraaneilla tehdyissä suodatuksissa MF-membraanit poistivat tehokkaasti fosforia (97 – 98 %) sekä kiintoainesta (100 %) jätevedestä. RO-membraanit alensivat fosfori- (100 %) ja typpipitoisuutta (90 – 94 %) tehokkaasti, poistaen myös liuenneita orgaanisia yhdisteitä (DOC, 90 – 94 %). Mikrosuodatukseen perustuvilla onttokuitumembraaneilla saavutettiin tehokkaan fosforinpoiston lisäksi tasainen kapasiteetti suodatuksen aikaista puhdistusmene-telmää optimoimalla. Pitoisuusalenemat olivat myös erittäin korkeita fosforille (97 – 99 %), kiintoaineelle (100 %), sameudelle (96 – 99 %) sekä COD:lle (38 – 55 %). Tulosten perusteella membraanitekniikkaan perustuva onttokuitusuodatus olisi tehokas ja toimiva jälkikäsittelyprosessi fosforinpoistoon ja jäteveden laadun pa-rantamiseen. Typen poistamiseen parhaiten toimi RO-membraani.

Imaging techniques applied for detection of secretion, transgene delivery and G proteincoupled receptors in reproductive and endocrine cells in vivo and in vitro

Post-testicular sperm maturation occurs in the epididymis. The ion concentration and proteins secreted into the epididymal lumen, together with testicular factors, are believed to be responsible for the maturation of spermatozoa. Disruption of the maturation of spermatozoa in the epididymis provides a promising strategy for generating a male contraceptive. However, little is known about the proteins involved. For drug development, it is also essential to have tools to study the function of these proteins in vitro. One approach for screening novel targets is to study the secretory products of the epididymis or the G protein-coupled receptors (GPCRs) that are involved in the maturation process of the spermatozoa. The modified Ca2+ imaging technique to monitor release from PC12 pheochromocytoma cells can also be applied to monitor secretory products involved in the maturational processes of spermatozoa. PC12 pheochromocytoma cells were chosen for evaluation of this technique as they release catecholamines from their cell body, thus behaving like endocrine secretory cells. The results of the study demonstrate that depolarisation of nerve growth factor -differentiated PC12 cells releases factors which activate nearby randomly distributed HEL erythroleukemia cells. Thus, during the release process, the ligands reach concentrations high enough to activate receptors even in cells some distance from the release site. This suggests that communication between randomly dispersed cells is possible even if the actual quantities of transmitter released are extremely small. The development of a novel method to analyse GPCR-dependent Ca2+ signalling in living slices of mouse caput epididymis is an additional tool for screening for drug targets. By this technique it was possible to analyse functional GPCRs in the epithelial cells of the ductus epididymis. The results revealed that, both P2X- and P2Y-type purinergic receptors are responsible for the rapid and transient Ca2+ signal detected in the epithelial cells of caput epididymides. Immunohistochemical and reverse transcriptase-polymerase chain reaction (RTPCR) analyses showed the expression of at least P2X1, P2X2, P2X4 and P2X7, and P2Y1 and P2Y2 receptors in the epididymis. Searching for epididymis-specific promoters for transgene delivery into the epididymis is of key importance for the development of specific models for drug development. We used EGFP as the reporter gene to identify proper promoters to deliver transgenes into the epithelial cells of the mouse epididymis in vivo. Our results revealed that the 5.0 kb murine Glutathione peroxidase 5 (GPX5) promoter can be used to target transgene expression into the epididymis while the 3.8 kb Cysteine-rich secretory protein-1 (CRISP-1) promoter can be used to target transgene expression into the testis. Although the visualisation of EGFP in living cells in culture usually poses few problems, the detection of EGFP in tissue sections can be more difficult because soluble EGFP molecules can be lost if the cell membrane is damaged by freezing, sectioning, or permeabilisation. Furthermore, the fluorescence of EGFP is dependent on its conformation. Therefore, fixation protocols that immobilise EGFP may also destroy its usefulness as a fluorescent reporter. We therefore developed a novel tissue preparation and preservation techniques for EGFP. In addition, fluorescence spectrophotometry with epididymal epithelial cells in suspension revealed the expression of functional purinergic, adrenergic, cholinergic and bradykinin receptors in these cell lines (mE-Cap27 and mE-Cap28). In conclusion, we developed new tools for studying the role of the epididymis in sperm maturation. We developed a new technique to analyse GPCR dependent Ca2+ signalling in living slices of mouse caput epididymis. In addition, we improved the method of detecting reporter gene expression. Furthermore, we characterised two epididymis-specific gene promoters, analysed the expression of GPCRs in epididymal epithelial cells and developed a novel technique for measurement of secretion from cells.

Micronization of Pharmaceuticals and Food Ingredients using Supercritical Fluid Techniques

Micronization techniques based on supercritical fluids (SCFs) are promising for the production of particles with controlled size and distribution. The interest of the pharmaceutical field in the development of SCF techniques is increasing due to the need for clean processes, reduced consumption of energy, and to their several possible applications. The food field is still far from the application of SCF micronization techniques, but there is increasing interest mainly for the processing of products with high added value. The aim of this study is to use SCF micronization techniques for the production of particles of pharmaceuticals and food ingredients with controlled particle size and morphology, and to look at their production on semi-industrial scale. The results obtained are also used to understand the processes from the perspective of broader application within the pharmaceutical and food industries. Certain pharmaceuticals, a biopolymer and a food ingredient have been tested using supercritical antisolvent micronization (SAS) or supercritical assisted atomization (SAA) techniques. The reproducibility of the SAS technique has been studied using physically different apparatuses and on both laboratory and semi-industrial scale. Moreover, a comparison between semi-continuous and batch mode has been performed. The behaviour of the system during the SAS process has been observed using a windowed precipitation vessel. The micronized powders have been characterized by particle size and distribution, morphology and crystallinity. Several analyses have been performed to verify if the SCF process modified the structure of the compound or caused degradation or contamination of the product. The different powder morphologies obtained have been linked to the position of the process operating point with respect to the vapour-liquid equilibrium (VLE) of the systems studied, that is, mainly to the position of the mixture critical point (MCP) of the mixture. Spherical micro, submicro- and nanoparticles, expanded microparticles (balloons) and crystals were obtained by SAS. The obtained particles were amorphous or with different degrees of crystallinity and, in some cases, had different pseudo-polymorphic or polymorphic forms. A compound that could not be processed using SAS was micronized by SAA, and amorphous particles were obtained, stable in vials at room temperature. The SCF micronization techniques studied proved to be effective and versatile for the production of particles for several uses. Furthermore, the findings of this study and the acquired knowledge of the proposed processes can allow a more conscious application of SCF techniques to obtain products with the desired characteristics and enable the use of their principles for broader applications.

Surface studies of limestones and dolostones : characterisation using various techniques and batch dissolution experiments with hydrochloric acid solutions

In this thesis, stepwise titration with hydrochloric acid was used to obtain chemical reactivities and dissolution rates of ground limestones and dolostones of varying geological backgrounds (sedimentary, metamorphic or magmatic). Two different ways of conducting the calculations were used: 1) a first order mathematical model was used to calculate extrapolated initial reactivities (and dissolution rates) at pH 4, and 2) a second order mathematical model was used to acquire integrated mean specific chemical reaction constants (and dissolution rates) at pH 5. The calculations of the reactivities and dissolution rates were based on rate of change of pH and particle size distributions of the sample powders obtained by laser diffraction. The initial dissolution rates at pH 4 were repeatedly higher than previously reported literature values, whereas the dissolution rates at pH 5 were consistent with former observations. Reactivities and dissolution rates varied substantially for dolostones, whereas for limestones and calcareous rocks, the variation can be primarily explained by relatively large sample standard deviations. A list of the dolostone samples in a decreasing order of initial reactivity at pH 4 is: 1) metamorphic dolostones with calcite/dolomite ratio higher than about 6% 2) sedimentary dolostones without calcite 3) metamorphic dolostones with calcite/dolomite ratio lower than about 6% The reactivities and dissolution rates were accompanied by a wide range of experimental techniques to characterise the samples, to reveal how different rocks changed during the dissolution process, and to find out which factors had an influence on their chemical reactivities. An emphasis was put on chemical and morphological changes taking place at the surfaces of the particles via X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM). Supporting chemical information was obtained with X-Ray Fluorescence (XRF) measurements of the samples, and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) measurements of the solutions used in the reactivity experiments. Information on mineral (modal) compositions and their occurrence was provided by X-Ray Diffraction (XRD), Energy Dispersive X-ray analysis (EDX) and studying thin sections with a petrographic microscope. BET (Brunauer, Emmet, Teller) surface areas were determined from nitrogen physisorption data. Factors increasing chemical reactivity of dolostones and calcareous rocks were found to be sedimentary origin, higher calcite concentration and smaller quartz concentration. Also, it is assumed that finer grain size and larger BET surface areas increase the reactivity although no certain correlation was found in this thesis. Atomic concentrations did not correlate with the reactivities. Sedimentary dolostones, unlike metamorphic ones, were found to have porous surface structures after dissolution. In addition, conventional (XPS) and synchrotron based (HRXPS) X-ray Photoelectron Spectroscopy were used to study bonding environments on calcite and dolomite surfaces. Both samples are insulators, which is why neutralisation measures such as electron flood gun and a conductive mask were used. Surface core level shifts of 0.7 ± 0.1 eV for Ca 2p spectrum of calcite and 0.75 ± 0.05 eV for Mg 2p and Ca 3s spectra of dolomite were obtained. Some satellite features of Ca 2p, C 1s and O 1s spectra have been suggested to be bulk plasmons. The origin of carbide bonds was suggested to be beam assisted interaction with hydrocarbons found on the surface. The results presented in this thesis are of particular importance for choosing raw materials for wet Flue Gas Desulphurisation (FGD) and construction industry. Wet FGD benefits from high reactivity, whereas construction industry can take advantage of slow reactivity of carbonate rocks often used in the facades of fine buildings. Information on chemical bonding environments may help to create more accurate models for water-rock interactions of carbonates.