21 resultados para 637.5

em Helda - Digital Repository of University of Helsinki


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Solar ultraviolet (UV) radiation has a broad range of effects concerning life on Earth. Soon after the mid-1980s, it was recognized that the stratospheric ozone content was declining over large areas of the globe. Because the stratospheric ozone layer protects life on Earth from harmful UV radiation, this lead to concern about possible changes in the UV radiation due to anthropogenic activity. Initiated by this concern, many stations for monitoring of the surface UV radiation were founded in the late 1980s and early 1990s. As a consequence, there is an apparent lack of information on UV radiation further in the past: measurements cannot tell us how the UV radiation levels have changed on time scales of, for instance, several decades. The aim of this thesis was to improve our understanding of past variations in the surface UV radiation by developing techniques for UV reconstruction. Such techniques utilize commonly available meteorological data together with measurements of the total ozone column for reconstructing, or estimating, the amount of UV radiation reaching Earth's surface in the past. Two different techniques for UV reconstruction were developed. Both are based on first calculating the clear-sky UV radiation using a radiative transfer model. The clear-sky value is then corrected for the effect of clouds based on either (i) sunshine duration or (ii) pyranometer measurements. Both techniques account also for the variations in the surface albedo caused by snow, whereas aerosols are included as a typical climatological aerosol load. Using these methods, long time series of reconstructed UV radiation were produced for five European locations, namely Sodankylä and Jokioinen in Finland, Bergen in Norway, Norrköping in Sweden, and Davos in Switzerland. Both UV reconstruction techniques developed in this thesis account for the greater part of the factors affecting the amount of UV radiation reaching the Earth's surface. Thus, they are considered reliable and trustworthy, as suggested also by the good performance of the methods. The pyranometer-based method shows better performance than the sunshine-based method, especially for daily values. For monthly values, the difference between the performances of the methods is smaller, indicating that the sunshine-based method is roughly as good as the pyranometer-based for assessing long-term changes in the surface UV radiation. The time series of reconstructed UV radiation produced in this thesis provide new insight into the past UV radiation climate and how the UV radiation has varied throughout the years. Especially the sunshine-based UV time series, extending back to 1926 and 1950 at Davos and Sodankylä, respectively, also put the recent changes driven by the ozone decline observed over the last few decades into perspective. At Davos, the reconstructed UV over the period 1926-2003 shows considerable variation throughout the entire period, with high values in the mid-1940s, early 1960s, and in the 1990s. Moreover, the variations prior to 1980 were found to be caused primarily by variations in the cloudiness, while the increase of 4.5 %/decade over the period 1979-1999 was supported by both the decline in the total ozone column and changes in the cloudiness. Of the other stations included in this work, both Sodankylä and Norrköping show a clear increase in the UV radiation since the early 1980s (3-4 %/decade), driven primarily by changes in the cloudiness, and to a lesser extent by the diminution of the total ozone. At Jokioinen, a weak increase was found, while at Bergen there was no considerable overall change in the UV radiation level.

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Aims. The beginning point of this research was confusion between studies claiming, that children mature Metalinguistic to read at 6-7 of age, and the fact, that in Montessori playschools children easily start writing and reading at age 3 to 5. Aim was also find out how conception of slow Metalinguistic development has started, and if there is some evidence of phoneme awareness of reading of young children in the field of research of reading. Aim was also seek evidence of the sensitive period of reading as Montessori described it. The research also wanted to turn up, if phoneme awareness only develops in children, who work with graphemes and with reading, or could it be found in children, who do not. The mean was to research how the Montessori reading material supports child’s Metalinguistic development, when child begins learning to read. The research plans to represent knowledge about how young children learn to write and read. Methods. Research performed in ordinary kindergarten and in Montessori playschool in Espoo. In kindergarten observed six children, age 3-4, at eight grapheme-rhyme sessions from January to April 2007, and conducting a test based on Chaney’s (1992) study of phoneme awareness of young children. In Montessori kindergarten were observed 17 children about their phoneme awareness and reading competition from January 2007 to March 2008. Their developments in reading were also measured three times from 1.9.07 to 20.3.08 with classification constructed for this study, loosely based on Chall’s (1983) reading stages. The Montessori reading material was analyzed about the influence they have to a child’s Metalinguistic development. This was done based to theory and its concepts from the field of research of reading; phoneme awareness, morphological, syntactical and semantic consciousness. Results and conclusions. Research proved that children 3-5 have naturally developed phoneme awareness. In kindergarten and in Montessori playschool children between 2 and 4 could do phoneme synthesis, and in the latter they also could do phoneme segmentation of words. Montessori reading material guided children gradually, except to read, also to observe and absorb Metalinguistic knowledge. Children learned to write and read. At the last evaluating day almost 50 % of children write and read clauses or stories, and 82 % could read at least words. Children can develop Metalinguistic awareness, while using the Montessori materials for learning to write and read. To reach literacy is easy for children because of their phoneme awareness.

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The purpose of this study is to examine the reception of Matthew 5 in Martin Luther s sermons; in other words to investigate how Luther interprets and applies Jesus teaching of the better righteousness and the law in Mt 5. The study applies the reception-historical approach and contributes to the history of effects and the history of interpretation in New Testament exegesis. The study shows that Luther understands the better righteousness of Mt 5 as good works and fulfillment of the law. Luther s interpretation coheres with the intention of the Evangelist, even if Luther s overall concept of righteousness is foreign to Matthew. In Luther s view righteousness is twofold: The greater righteousness of Mt 5 is the second and the actual righteousness (iustitia activa), which follows the first and the foreign righteousness (iustitia passiva). The first righteousness (faith) is for Luther the work of God, while the second righteousness (good works) is co-operation between a Christian and God. In this co-operation the law, as it is taught by Jesus, is not the opposite of the gospel, but the gospel itself in the sense of Christ as an example . The task of the law is to show the dependence of a Christian on God and to help one to love and to serve one s neighbour (brothers as well as enemies) properly. The study underlines a feature in Luther s thinking that has received little attention in Lutheran theology: Luther insists on preaching the law to Christians. In his view Mt 5 is directed to all Christians and particularly to pastors, for whom Jesus here gives an example of how to preach the law. Luther believes similarly to Matthew that Jesus reveals the real meaning of Mosaic Law and confirms its validity for Christians in Mt 5. Like Matthew, Luther insists on the practicability of the commandments of Mt 5 in his view Christians fulfil the law also with joy yet his interpretation of Mt 5 attenuates the radical nature of its commandments. Luther s reception of the individual pericopes of Mt 5 is considerably generative and occasionally contradictory, which is explained by the following factors, among others: Luther receives many ideas from tradition and reads them and his own theological concepts into Matthew s Gospel. He interprets Mt 5 through his understanding of some Old Testament passages as well as Paul. Most of all, Luther s reception of Mt 5 is shaped by his own experience as a preacher, by his relation to his religious enemies, rulers and to the congregation of Wittenberg. Here Luther shares with Matthew the experience of being opposed and concern about the upright living of the believers, which in both cases also explains the polemical tone of the paraenesis.

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Autuus on katsojan silmässä: lukijakeskeinen tutkimus autuaaksijulistuksista Matt. 5 : 1-12 on reseptioanalyyttisellä metodilla tehty tutkimus siitä, miten akateeminen tutkimuskirjallisuus ja kymmenen valikoitua Jeesus-elokuvaa ovat ymmärtäneet autuaaksijulistusten merkityksen. Kartoitettuaan autuaaksijulistusten tulkintahistoriaa ja Jeesus-elokuvien kulttuurihistoriaa tutkielma kääntyy reseptiohistorialliseksi analyysiksi. Akateemisen tutkimuskirjallisuuden ja Jeesus-elokuvien esittämät tulkinnat Matteuksen evankeliumin autuaaksijulistuksista rinnas-tetaan suhteessa autuaaksijulistusten tyyliin, sisältöön, rakenteeseen ja merkitykseen. Autuaaksijulistusten tyylin tulkinnan analysointi tapahtuu vertailemalla millainen narratiivinen sijainti autuaaksijulistuksille on tarinassa annettu, millaiseksi elokuvat ja tutkimuskirjallisuus tulkitsevat julistusten esitykselliset puitteet sekä mitä näkemyksiä niillä on julistusten kohdeyleisöstä ja Jeesuksen esiintymistavasta. Autuaaksijulistusten sisällön analysointi tarkoittaa yksittäisten autuaaksijulistusten merkityksen selvittelyä. Tämä tapahtuu edelleen Jeesus-elokuvien ja tutkimuskirjallisuuden tekemiä tulkintoja vertailemalla. Näiden lisäksi tekijä esittää oman käännöksensä autuaaksijulistuksista eksegeettisen analyysin keinoin. Käännöksen tavoitteena ei kuitenkaan ole sanatarkkuus, vaan dynaamisuus lukijan tulkinnan säilyttämiseksi. Autuaaksijulistusten rakenteen analysointi esittelee muutamia erilaisia malleja, joiden mukaan tutkimuskirjallisuudessa Matteuksen evankeliumin autuaaksijulistuksia on ryhmitelty. Tässä alaluvussa elokuva-aineiston ja tutkimuskirjallisuuden erot ovat selkeimmin näkyvillä, sillä elokuvat pyrkivät ryhmittelyn sijasta luomaan autuaaksijulistuksille kokonaan uuden rakenteen, joka sopii elokuvakerrontaan julistuslistaa paremmin. Autuaaksijulistusten merkitystä analysoitaessa tutkielmassa asetetaan rinnan kolme Jeesus-elokuvaa, jotka edustavat tulkintahistoriasta tuttuja tulkinnallisia pääsuuntia: autuaaksijulistukset tulkitaan joko eettisiksi kehotuksiksi tai lupauksiksi armosta. Kolmas Jeesus-elokuva edustaa kontroversiaalista näkemystä, joka kiistää molemmat edellä mainitut tulkintatavat. Johtopäätöksissä osoitetaan reseptiohistorialliseen analyysiin viitaten, että tulkintojen muotoutuminen ei ole yksinkertaista. Tulkintaan vaikuttavat paitsi tulkitsijan ennakkokäsitykset, myös tulkittava teksti ja tulkintatilanne. Johtopäätöksissä puolustetaan myös populaarikulttuurin teologisten elementtien tutkimusta osana eksegetiikkaa.

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The work covered in this thesis is focused on the development of technology for bioconversion of glucose into D-erythorbic acid (D-EA) and 5-ketogluconic acid (5-KGA). The task was to show on proof-of-concept level the functionality of the enzymatic conversion or one-step bioconversion of glucose to these acids. The feasibility of both studies to be further developed for production processes was also evaluated. The glucose - D-EA bioconversion study was based on the use of a cloned gene encoding a D-EA forming soluble flavoprotein, D-gluconolactone oxidase (GLO). GLO was purified from Penicillium cyaneo-fulvum and partially sequenced. The peptide sequences obtained were used to isolate a cDNA clone encoding the enzyme. The cloned gene (GenBank accession no. AY576053) is homologous to the other known eukaryotic lactone oxidases and also to some putative prokaryotic lactone oxidases. Analysis of the deduced protein sequence of GLO indicated the presence of a typical secretion signal sequence at the N-terminus of the enzyme. No other targeting/anchoring signals were found, suggesting that GLO is the first known lactone oxidase that is secreted rather than targeted to the membranes of the endoplasmic reticulum or mitochondria. Experimental evidence supports this analysis, as near complete secretion of GLO was observed in two different yeast expression systems. Highest expression levels of GLO were obtained using Pichia pastoris as an expression host. Recombinant GLO was characterised and the suitability of purified GLO for the production of D-EA was studied. Immobilised GLO was found to be rapidly inactivated during D-EA production. The feasibility of in vivo glucose - D-EA conversion using a P. pastoris strain co-expressing the genes of GLO and glucose oxidase (GOD, E.C. 1.1.3.4) of A. niger was demonstrated. The glucose - 5-KGA bioconversion study followed a similar strategy to that used in the D-EA production research. The rationale was based on the use of a cloned gene encoding a membrane-bound pyrroloquinoline quinone (PQQ)-dependent gluconate 5-dehydrogenase (GA 5-DH). GA 5-DH was purified to homogeneity from the only source of this enzyme known in literature, Gluconobacter suboxydans, and partially sequenced. Using the amino acid sequence information, the GA 5-DH gene was cloned from a genomic library of G. suboxydans. The cloned gene was sequenced (GenBank accession no. AJ577472) and found to be an operon of two adjacent genes encoding two subunits of GA 5-DH. It turned out that GA 5-DH is a rather close homologue of a sorbitol dehydrogenase from another G. suboxydans strain. It was also found that GA 5-DH has significant polyol dehydrogenase activity. The G. suboxydans GA 5-DH gene was poorly expressed in E. coli. Under optimised conditions maximum expression levels of GA 5-DH did not exceed the levels found in wild-type G. suboxydans. Attempts to increase expression levels resulted in repression of growth and extensive cell lysis. However, the expression levels were sufficient to demonstrate the possibility of bioconversion of glucose and gluconate into 5-KGA using recombinant strains of E. coli. An uncharacterised homologue of GA 5-DH was identified in Xanthomonas campestris using in silico screening. This enzyme encoded by chromosomal locus NP_636946 was found by a sequencing project of X. campestris and named as a hypothetical glucose dehydrogenase. The gene encoding this uncharacterised enzyme was cloned, expressed in E. coli and found to encode a gluconate/polyol dehydrogenase without glucose dehydrogenase activity. Moreover, the X. campestris GA 5-DH gene was expressed in E. coli at nearly 30 times higher levels than the G. suboxydans GA 5-DH gene. Good expressability of the X. campestris GA-5DH gene makes it a valuable tool not only for 5-KGA production in the tartaric acid (TA) bioprocess, but possibly also for other bioprocesses (e.g. oxidation of sorbitol into L-sorbose). In addition to glucose - 5-KGA bioconversion, a preliminary study of the feasibility of enzymatic conversion of 5-KGA into TA was carried out. Here, the efficacy of the first step of a prospective two-step conversion route including a transketolase and a dehydrogenase was confirmed. It was found that transketolase convert 5-KGA into TA semialdehyde. A candidate for the second step was suggested to be succinic dehydrogenase, but this was not tested. The analysis of the two subprojects indicated that bioconversion of glucose to TA using X. campestris GA 5-DH should be prioritised first and the process development efforts in future should be focused on development of more efficient GA 5-DH production strains by screening a more suitable production host and by protein engineering.

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Plasma phospholipid transfer protein (PLTP) plays a crucial role in high-density lipoprotein (HDL) metabolism and reverse cholesterol transport (RCT). It mediates the generation of pre-beta-HDL particles, enhances the cholesterol efflux from peripheral cells to pre-beta-HDL, and metabolically maintains the plasma HDL levels by facilitating the transfer of post-lipolytic surface remnants of triglyceride-rich lipoproteins to HDL. In addition to the antiatherogenic properties, recent findings indicate that PLTP has also proatherogenic characteristics, and that these opposite characteristics of PLTP are dependent on the site of PLTP expression and action. In human plasma, PLTP exists in a high-activity (HA-PLTP) and a low-activity form (LA-PLTP), which are associated with macromolecular complexes of different size and composition. The aims of this thesis were to isolate the two PLTP forms from human plasma, to characterize the molecular complexes in which the HA- and LA-PLTP reside, and to study the interactions of the PLTP forms with apolipoproteins (apo) and the ability of apolipoproteins to regulate PLTP activity. In addition, we aimed to study the distribution of the two PLTP forms in a Finnish population sample as well as to find possible regulatory factors for PLTP by investigating the influence of lipid and glucose metabolism on the balance between the HA- and LA-PLTP. For these purposes, an enzyme-linked immunosorbent assay (ELISA) capable of determining the serum total PLTP concentration and quantitating the two PLTP forms separately was developed. In this thesis, it was demonstrated that the HA-PLTP isolated from human plasma copurified with apoE, whereas the LA-PLTP formed a complex with apoA-I. The separation of these two PLTP forms was carried out by a dextran sulfate (DxSO4)-CaCl2 precipitation of plasma samples before the mass determination. A similar immunoreactivity of the two PLTP forms in the ELISA could be reached after a partial sample denaturation by SDS. Among normolipidemic Finnish individuals, the mean PLTP mass was 6.6 +/- 1.5 mg/l and the mean PLTP activity 6.6 +/- 1.7 umol/ml/h. Of the serum PLTP concentration, almost 50% represented HA-PLTP. The results indicate that plasma HDL levels could regulate PLTP concentration, while PLTP activity could be regulated by plasma triglyceride-rich very low-density lipoprotein (VLDL) concentration. Furthermore, new evidence is presented that PLTP could also play a role in glucose metabolism. Finally, both PLTP forms were found to interact with apoA-I, apoA-IV, and apoE. In addition, both apoE and apoA-IV, but not apoA-I, were capable of activating the LA-PLTP. These findings suggest that the distribution of the HA- and LA-PLTP in human plasma is subject to dynamic regulation by apolipoproteins.

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Bone mass accrual and maintenance are regulated by a complex interplay between genetic and environmental factors. Recent studies have revealed an important role for the low-density lipoprotein receptor-related protein 5 (LRP5) in this process. The aim of this thesis study was to identify novel variants in the LRP5 gene and to further elucidate the association of LRP5 and its variants with various bone health related clinical characteristics. The results of our studies show that loss-of-function mutations in LRP5 cause severe osteoporosis not only in homozygous subjects but also in the carriers of these mutations, who have significantly reduced bone mineral density (BMD) and increased susceptibility to fractures. In addition, we demonstrated for the first time that a common polymorphic LRP5 variant (p.A1330V) was associated with reduced peak bone mass, an important determinant of BMD and osteoporosis in later life. The results from these two studies are concordant with results seen in other studies on LRP5 mutations and in association studies linking genetic variation in LRP5 with BMD and osteoporosis. Several rare LRP5 variants were identified in children with recurrent fractures. Sequencing and multiplex ligation-dependent probe amplification (MLPA) analyses revealed no disease-causing mutations or whole-exon deletions. Our findings from clinical assessments and family-based genotype-phenotype studies suggested that the rare LRP5 variants identified are not the definite cause of fractures in these children. Clinical assessments of our study subjects with LPR5 mutations revealed an unexpectedly high prevalence of impaired glucose tolerance and dyslipidaemia. Moreover, in subsequent studies we discovered that common polymorphic LRP5 variants are associated with unfavorable metabolic characteristics. Changes in lipid profile were already apparent in pre-pubertal children. These results, together with the findings from other studies, suggest an important role for LRP5 also in glucose and lipid metabolism. Our results underscore the important role of LRP5 not only in bone mass accrual and maintenance of skeletal health but also in glucose and lipid metabolism. The role of LRP5 in bone metabolism has long been studied, but further studies with larger study cohorts are still needed to evaluate the specific role of LRP5 variants as metabolic risk factors.

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The present collection of articles is based on international conference that was held in Seinäjoki, Finland in February 2009. The topic of the conference was Effective Rural and Urban Policies and it was organised in co-operation between University Consortium of Seinäjoki, Seinäjoki Technology Centre and City of Seinäjoki. The presented papers approached the drivers of regional development from several aspects and in different kind of regional contexts across various countries. As a whole the different contributions formed a comprehensive story of those factors that are shaping the development of both rural and urban regions in global economy. The role of local innovation environment and dynamic of social processes that are ‘oiling’ the interaction between individuals within networks inspired several scholars. Also development of physical infrastructure as well as the recent development of economical models that can predict the regional impacts of large scale investments was discussed in many presentations. Clear focus with cultural and disciplinary diversity formed a fruitful basis for the conference and it was easy to learn something new. On the behalf of all organisers I would like to thank all participants of the conference and especially our foreign colleges who had travelled from distances to spend some winter days in Seinäjoki. As we all know this kind of publication does not appear automatically. All authors have done great job by finding time for writing from their busy schedules. Terttu Poranen and Jaana Huhtala have taken care of the technical editing of this publication. Sari Soini was the main organiser of conference and she has also as a editor kept the required pressure to finalize this book. In addition to University of Helsinki, conference was financially supported by the University of Vaasa, City of Seinäjoki, Lähivakuutus and Regional Centre Programme. These contributions are highly appreciated.