126 resultados para käsittely


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Wood-degrading fungi are able to degrade a large range of recalcitrant pollutants which resemble the lignin biopolymer. This ability is attributed to the production of lignin-modifying enzymes, which are extracellular and non-specific. Despite the potential of fungi in bioremediation, there is still an understanding gap in terms of the technology. In this thesis, the feasibility of two ex situ fungal bioremediation methods to treat contaminated soil was evaluated. Treatment of polycyclic aromatic hydrocarbons (PAHs)-contaminated marsh soil was studied in a stirred slurry-phase reactor. Due to the salt content in marsh soil, fungi were screened for their halotolerance, and the white-rot fungi Lentinus tigrinus, Irpex lacteus and Bjerkandera adusta were selected for further studies. These fungi degraded 40 - 60% of a PAH mixture (phenanthrene, fluoranthene, pyrene and chrysene) in a slurry-phase reactor (100 ml) during 30 days of incubation. Thereafter, B. adusta was selected to scale-up and optimize the process in a 5 L reactor. Maximum degradation of dibenzothiophene (93%), fluoranthene (82%), pyrene (81%) and chrysene (83%) was achieved with the free mycelium inoculum of the highest initial biomass (2.2 g/l). In autoclaved soil, MnP was the most important enzyme involved in PAH degradation. In non-sterile soil, endogenous soil microbes together with B. adusta also degraded the PAHs extensively, suggesting a synergic action between soil microbes and the fungus. A fungal solid-phase cultivation method to pretreat contaminated sawmill soil with high organic matter content was developed to enhance the effectiveness of the subsequent soil combustion. In a preliminary screening of 146 fungal strains, 28 out of 52 fungi, which extensively colonized non-sterile contaminated soil, were litter-decomposing fungi. The 18 strains further selected were characterized by their production of lignin-modifying and hydrolytic enzymes, of which MnP and endo-1,4-β-glucanase were the main enzymes during cultivation on Scots pine (Pinus sylvestris) bark. Of the six fungi selected for further tests, Gymnopilus luteofolius, Phanerochaete velutina, and Stropharia rugosoannulata were the most active soil organic matter degraders. The results showed that a six-month pretreatment of sawmill soil would result in a 3.5 - 9.5% loss of organic matter, depending on the fungus applied. The pretreatment process was scaled-up for a 0.56 m3 reactor, in which perforated plastic tubes filled with S. rugosoannulata growing on pine bark were introduced into the soil. The fungal pretreatment resulted in a soil mass loss of 30.5 kg, which represents 10% of the original soil mass (308 kg). Despite the fact that Scots pine bark contains several antimicrobial compounds, it was a suitable substrate for fungal growth and promoter of the production of oxidative enzymes, as well as an excellent and cheap natural carrier of fungal mycelium. This thesis successfully developed two novel fungal ex situ bioremediation technologies and introduce new insights for their further full-scale application. Ex situ slurry-phase fungal reactors might be applied in cases when the soil has a high water content or when the contaminant bioavailability is low; for example, in wastewater treatment plants to remove pharmaceutical residues. Fungal solid-phase bioremediation is a promising remediation technology to ex situ or in situ treat contaminated soil.

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This study examines how sex education is currently developed and implemented in Greek primary schools. The four publications that comprise it explore the following themes: (1) the position and visibility of sex education as one of the topics for health education programme development; (2) the inhibiting and enhancing factors in the development and implementation of primary school sex education programmes; (3) how issues of sex, sexuality, the human body and romantic relationships are visually and textually represented in primary school textbooks; (4) the impact of sex education on teachers and pupils; and (5) teachers experiences as practitioners who deal with sexuality- related issues at school. -- The research was based on conducting multiple sub-studies using a mixed-methods approach. Specifically, qualitative and quantitative data were collected and analysed. The initial quantitative data that had been obtained by questionnaire was followed by the collection and analysis of qualitative data. The qualitative data were acquired by way of examining one particular case, various texts, interviews with teachers and self-reflective material. The results of the sub-studies are presented in a more detailed manner in the study s four publications. -- In general, the sub-studies found that sex education as an educational activity occupies a marginal place within the instructional practices of Greek primary school teachers, since the subject is hardly mentioned in classroom material, such as textbooks. However, engaging in the provision of sex education programmes can become a meaningful and rewarding experience for many teachers as well as pupils and their families. Further, teachers classroom experiences pointed to school settings as sexualized environments. These contextual factors and conditions nevertheless affected teachers practices and perceptions on a personal and professional level.Health indicators in Greece provide a picture of a population that faces various sexual health related problems. However, as many studies (including this work) indicate, sex education programmes that meet specific standards can have a positive impact on students overall health and well-being. Sex education teaching has always been a controversial issue. Its successful implementation in Greece demands knowledgeable educators and responsible policy-makers. The findings of this study suggest that the content of Greek primary school textbooks needs to be revised in order to include texts and pictures that deal with the human body and human sexuality, encourage pupils to become involved in designing the content and methods of programmes and give teachers the opportunity to reflect on and discuss their experiences. Keywords: sex education, primary school, Greece

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Despite its bad reputation in the mass media, cholesterol is an indispensable constituent of cellular membranes and vertebrate life. It is, however, also potentially lethal as it may accumulate in the arterial intima causing atherosclerosis or elsewhere in the body due to inherited conditions. Studying cholesterol in cells, and research on how the cell biology of cholesterol affects on system level is essential for a better understanding of the disease states associated with cholesterol and for the development of new therapies for these conditions. On its way to the cell, exogenous cholesterol traverses through endosomes, transport vesicles involved in internalizing material to cells, and needs to be transported out of this compartment. This endosomal pool of cholesterol is important for understanding both the common disorders of metabolism and the more rare hereditary disorders of cholesterol metabolism. The study of cholesterol in cells has been hampered by the lack of bright fluorescent sterol analogs that would resemble cholesterol enough to be used in cellular studies. In the first study of my thesis, we present a new sterol analog, Boron-Dipyrromethene (BODIPY)-cholesterol for visualizing sterols in living cells and organism. This fluorescent cholesterol derivative is shown to behave similarly to cholesterol both by atomic scale computer simulations and biochemical experiments. We characterize its localization inside different types of living cells and show that it can be used to study sterol trafficking in living organisms. Two sterol binding proteins associated with the endosomal membrane; the Niemann-Pick type C disease protein 1 (NPC1) and the Oxysterol Binding Protein Related Protein 1 (ORP1) are the subjects of the rest of this study. Sensing cholesterol on endosomes, transporting lipids away from this compartment and the effects these lipids play on cellular metabolism are considered. In the second study we characterize how the NPC1 protein affects lipid metabolism. We show that this cholesterol binding protein affects synthesis of triglycerides and that genetic polymorphisms or a genetic defect in the NPC1 gene affect triglyceride on the whole body level. These effects take place via regulation of carbon fluxes to different lipid classes in cells. In the third part we characterize the effects of another endosomal sterol binding protein, ORP1L on the function and motility of endosomes. Specifically we elucidate how a mutation in the ability of ORP1L to bind sterols affects its behavior in cells, and how a change in ORP1L levels in cells affects the localization, degradative capacity and motility of endosomes. In addition we show that ORP1L manipulations affect cholesterol balance also in macrophages, a cell type important for the development of atherosclerosis.

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Maaseutupolitiikan yhteistyöryhmä on pääosin poliittis-hallinnollisessa tilassa toimiva, uusi verkostomainen hallintasommitelma, jossa on mukana myös hallinnon ulkopuolisia toimijoita ja tahoja. Kokonaisuutta nimitetään tässä YTR-verkostoksi. Itsearvioinnin tarkoituksena oli argumentoida esiin YTR-verkoston toiminnan kriittiset kohdat. Arviointitutkimuksesta vastasi Helsingin yliopiston Ruralia-instituutti ja sen toteutti 25.8. – 31.12.2010 välisenä aikana tutkimusjohtaja, dosentti Torsti Hyyryläinen. Itsearviointiin osallistui valtioneuvoston viisivuotiseksi toimikaudeksi (2008-2013) nimeämän maaseutupolitiikan yhteistyöryhmän jäseniä ja varajäseniä. Kokoavana tuloksena esitetään seuraava analyysi: 1. YTR-verkoston tiedollinen kapasiteetti on vahva. 2. YTR-verkostolla on potentiaalisesti laajat suhderesurssit mutta ne ovat alihyödynnettyjä. 3. YTR-verkostolla on mobilisoitikapasiteettia mutta sen omat voimavarat ovat niukat. YTR-verkostolla on ollut keskeinen rooli maaseutupolitiikan muotoutumisessa ja kehittymisessä. Keskustelu maaseudun kehittämistä olisi Suomessa ollut oleellisesti vähäisempää, heikommin jäsenneltyä ja tietopääomaltaan suppeampaa ilman YTR-verkostoa. Verkostossa on monialaista asiantuntemusta, jonka perusteella se on kyennyt vastaamaan laajoihin maaseutupoliittisiin kommunikaatiotarpeisiin. Tästä yhtenä esimerkkinä on maaseutupoliittisen selonteon perusteellinen valmistelu ja monivaiheinen käsittely eduskunnassa vuonna 2010. Verkostosuhteiden hallinnan kehittäminen nousee arvioinnissa tärkeimmäksi YTR-verkoston toimintakyvyn, tuloksellisuuden ja vaikuttavuuden kehittämisen painopisteeksi. Verkosto näyttää saavuttaneen tärkeän kehitysvaiheen, josta ei päästä eteenpäin ilman sen kysymyksen pohdintaa, miten YTR-verkoston suhdekapasiteettia, eli suhteita keskeisiin sidosryhmiin voitaisiin kehittää. Valta on YTR-verkostossa komplisoiduinta ja ongelmallisinta juuri suhderesurssien alueilla. Se kiteytyy kysymykseen poliittisesta valmistelu- ja päätösvallasta, eli kenellä on legitiimi asema toisaalta muotoilla poliittiseen päätöksentekoon etenevät aloitteet ja lopulta tehdä poliittisesti sitovia päätöksiä koskien maaseutua ja sen kehittämistä. Medioiden vaikutusvallan huomioiminen on entistä tärkeämpää. Niiden suuntaan vahvemmin kommunikoimalla YTR-verkosto voi tulevaisuudessa lisätä vaikutusvaltaansa. Toistaiseksi lähes täysin käyttämätön potentiaali on sosiaalisen median verkostoissa, joihin YTR:n säikeet eivät vielä juurikaan ulotu. Suhdepääomassa on siis YTR:n voima ja samalla sen heikkous. Tämä johtopäätös on merkittävä erityisesti valtioneuvoston asettaman yhteistyöryhmän itsensä kannalta. Yhteistyöryhmän tulisi itse vapautua komiteamaisista työtavoista ja kehittää niitä monimuotoisemmiksi. Paikallaan on myös kysyä: mitä yhteistyöryhmän jäsenet ja jäsenyhteisöt ovat valmiita tekemään YTR:n suhderesurssien kehittämiseksi?

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English summary: On the efficiency of peat infiltration of sewage during various seasons and on its improvement

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English summary: Costs of purifying domestic sewage.

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English summary: Simultaneous precipitation together with extended aeration of municipal waterwaters.