28 resultados para Brown University.

em Helda - Digital Repository of University of Helsinki


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Large carnivore populations are currently recovering from past extirpation efforts and expanding back into their original habitats. At the same time human activities have resulted in very few wilderness areas left with suitable habitats and size large enough to maintain populations of large carnivores without human contact. Consequently the long-term future of large carnivores depends on their successful integration into landscapes where humans live. Thus, understanding their behaviour and interaction with surrounding habitats is of utmost importance in the development of management strategies for large carnivores. This applies also to brown bears (Ursus arctos) that were almost exterminated from Scandinavia and Finland at the turn of the century, but are now expanding their range with the current population estimates being approximately 2600 bears in Scandinavia and 840 in Finland. This thesis focuses on the large-scale habitat use and population dynamics of brown bears in Scandinavia with the objective to develop modelling approaches that support the management of bear populations. Habitat analysis shows that bear home ranges occur mainly in forested areas with a low level of human influence relative to surrounding areas. Habitat modelling based on these findings allows identification and quantification of the potentially suitable areas for bears in Scandinavia. Additionally, this thesis presents novel improvements to home range estimation that enable realistic estimates of the effective area required for the bears to establish a home range. This is achieved through fitting to the radio-tracking data to establish the amount of temporal autocorrelation and the proportion of time spent in different habitat types. Together these form a basis for the landscape-level management of the expanding population. Successful management of bears requires also assessment of the consequences of harvest on the population viability. An individual-based simulation model, accounting for the sexually selected infanticide, was used to investigate the possibility of increasing the harvest using different hunting strategies, such as trophy harvest of males. The results indicated that the population can sustain twice the current harvest rate. However, harvest should be changed gradually while carefully monitoring the population growth as some effects of increased harvest may manifest themselves only after a time-delay. The results and methodological improvements in this thesis can be applied to the Finnish bear population and to other large carnivores. They provide grounds for the further development of spatially-realistic management-oriented models of brow bear dynamics that can make projections of the future distribution of bears while accounting for the development of human activities.

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Cassava brown streak disease (CBSD) was described for the first time in Tanganyika (now Tanzania) about seven decades ago. Tanganyika (now Tanzania) about seven decades ago. It was endemic in the lowland areas of East Africa and inland parts of Malawi and caused by Cassava brown streak virus (CBSV; genus Ipomovirus; Potyviridae). However, in 1990s CBSD was observed at high altitude areas in Uganda. The causes for spread to new locations were not known.The present work was thus initiated to generate information on genetic variability, clarify the taxonomy of the virus or viruses associated with CBSD in Eastern Africa as well as to understand the evolutionary forces acting on their genes. It also sought to develop a molecular based diagnostic tool for detection of CBSD-associated virus isolates. Comparison of the CP-encoding sequences of CBSD-associated virus isolates collected from Uganda and north-western Tanzania in 2007 and the partial sequences available in Genbank revealed occurrence of two genetically distinct groups of isolates. Two isolates were selected to represent the two groups. The complete genomes of isolates MLB3 (TZ:Mlb3:07) and Kor6 (TZ:Kor6:08) obtained from North-Western (Kagera) and North-Eastern (Tanga) Tanzania, respectively, were sequenced. The genomes were 9069 and 8995 nucleotides (nt), respectively. They translated into polyproteins that were predicted to yield ten mature proteins after cleavage. Nine proteins were typical in the family Potyviridae, namely P1, P3, 6K1, CI, 6K2, VPg, NIa-Pro, NIb and CP, but the viruses did not contain HC-Pro. Interestingly, genomes of both isolates contained a Maf/HAM1-like sequence (HAM1h; 678 nucleotides, 25 kDa) recombined between the NIb and CP domains in the 3’-proximal part of the genomes. HAM1h was also identified in Euphorbia ringspot virus (EuRSV) whose sequence was in GenBank. The HAM1 gene is widely spread in both prokaryotes and eukaryotes. In yeast (Saccharomyces cerevisiae) it is known to be a nucleoside triphosphate (NTP) pyrophosphatase. Novel information was obtained on the structural variation at the N-termini of polyproteins of viruses in the genus Ipomovirus. Cucumber vein yellowing virus (CVYV) and Squash vein yellowing virus (SqVYV) contain a duplicated P1 (P1a and P1b) but lack the HC-Pro. On the other hand, Sweet potato mild mottle virus (SPMMV), has a single but large P1 and has HC-Pro. Both virus isolates (TZ:Mlb3:07 & TZ:Kor6:08) characterized in this study contained a single P1 and lacked the HC-Pro which indicates unique evolution in the family Potyviridae. Comparison of 12 complete genomes of CBSD-associated viruses which included two genomes characterized in this study, revealed genetic identity of 69.0–70.3% (nt) and amino acid (aa) identities of 73.6–74.4% at polyprotein level. Comparison was also made among 68 complete CP sequences, which indicated 69.0-70.3 and 73.6-74.4 % identity at nt and aa levels, respectively. The genetic variation was large enough for dermacation of CBSD-associated virus isolates into two distinct species. The name CBSV was retained for isolates that were related to CBSV isolates available in database whereas the new virus described for the first time in this study was named Ugandan cassava brown streak virus (UCBSV) by the International Committee on Virus Taxonomy (ICTV). The isolates TZ:Mlb3:07 and TZ:Kor6:08 belong to UCBSV and CBSV, respectively. The isolates of CBSV and UCBSV were 79.3-95.5% and 86.3-99.3 % identitical at nt level, respectively, suggesting more variation amongst CBSV isolates. The main sources of variation in plant viruses are mutations and recombination. Signals for recombination events were detected in 50% of isolates of each virus. Recombination events were detected in coding and non-coding (3’-UTR) sequences except in the 5’UTR and P3. There was no evidence for recombination between isolates of CBSV and UCBSV. The non-synonomous (dN) to synonomous (dS) nucleotide substitution ratio (ω) for the HAM1h and CP domains of both viruses were ≤ 0.184 suggesting that most sites of these proteins were evolving under strong purifying selection. However, there were individual amino acid sites that were submitted to adaptive evolution. For instance, adaptive evolution was detected in the HAM1h of UCBSV (n=15) where 12 aa sites were under positive selection (P< 0.05) but not in CBSV (n=12). The CP of CBSV (n=23) contained 12 aa sites (p<0.01) while only 5 aa sites in the CP gene of UCBSV were predicted to be submitted to positive selection pressure (p<0.01). The advantages offered by the aa sites under positive selection could not be established but occurrence of such sites in the terminal ends of UCBSV-HAMIh, for example, was interpreted as a requirement for proteolysis during polyprotein processing. Two different primer pairs that simultaneously detect UCBSV and CBSV isolates were developed in this study. They were used successfully to study distribution of CBSV, UCBSV and their mixed infections in Tanzania and Uganda. It was established that the two viruses co-infect cassava and that incidences of co-infection could be as high as 50% around Lake Victoria on the Tanzanian side. Furthermore, it was revealed for the first time that both UCBSV and CBSV were widely distributed in Eastern Africa. The primer pair was also used to confirm infection in a close relative of cassava, Manihot glaziovii (Müller Arg.) with CBSV. DNA barcoding of M. glaziovii was done by sequencing the matK gene. Two out of seven M. glaziovii from the coastal areas of Korogwe and Kibaha in north eastern Tanzania were shown to be infected by CBSV but not UCBSV isolates. Detection in M. glaziovii has an implication in control and management of CBSD as it is likely to serve as virus reservoir. This study has contributed to the understanding of evolution of CBSV and UCBSV, which cause CBSD epidemic in Eastern Africa. The detection tools developed in this work will be useful in plant breeding, verification of the phytosanitary status of materials in regional and international movement of germplasm, and in all diagnostic activities related to management of CBSD. Whereas there are still many issues to be resolved such as the function and biological significance of HAM1h and its origin, this work has laid a foundation upon which the studies on these aspects can be based.

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The use of forms of address in French films and their Finnish translations The use of forms of address constitutes an integral part of speakers’ communicative competence. In fact, they are not only used to assign to whom the speech is addressed, but also to construct the relationship between speakers. However, the choice of a suitable form is not necessarily evident in modern, pluralistic society. By the notion form of address, I refer to pronouns of address (tu vs. vous) and different nouns of address like names, titles (Monsieur, Madame, Mademoiselle), kinship terms, occupational terms, terms of endearment and insults. The purpose of the present thesis is, first, to study the semantic and pragmatic values of forms of address in dialogues of modern French films, and, second, their translation in Finnish subtitles. It is evident that film language is not spontaneous, but only a representation of authentic speech, and that subtitles are a written version of the original spoken language. Consequently, this thesis studies spoken fictive dialogues and their written translations. The methods applied in the study are the Interactional and Pragmatic Approach as well as Translatology. The role of forms of address in an interpersonal relationship is studied with dimensions of distance and power (Brown and Gilman 1960, Kerbrat-Orecchioni 1992), whereas the pragmatic dimension permits studying in particular the use of forms of address in speech acts (Kerbrat-Orecchioni 2001). The translation strategies are studied with the help of Venuti’s (1995) notions of foreignizing and domesticating strategies. The results of the thesis suggest that the pronoun use in the studied films is usually reciprocal. However, the relations of power have not disappeared, but are expressed in a more discrete manner with nouns of address (for instance vous + Docteur vs. vous + Anita). The use of the pronoun of address vous seems still to be common, but increased intimacy is expressed by accompanying familiar nouns of address like first names. The nominal forms of address accompany different speech acts, but not in a systematic manner. In a dialogue they appear usually in the first speech act, and more rarely in the response, but not in both. In addition, they have an important role in the mechanics of conversation. The translators here face multiple demands, and their translations seem mostly to be a compromise between foreignizing and domesticating strategies.

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Käsitteillä svengi ja groove viitataan useimmiten kappaleen tietyn tulkinnan eli esityksen pääasiallisesti rytmisten ominaisuuksien laatuun. Tutkimuksen tavoitteena on kehittää musiikin rytmiikkaan ja hienorytmiikkaan keskittyviä musiikkikognitiivisia analyysimetodeja, joita soveltamalla nämä ominaisuudet voitaisiin tavoittaa. Käsitteiden monitulkintaisuus, joka tuodaan esiin tutkimuksen alussa aiheuttaa tälle monenlaisia haasteita. -- Tutkimuksen rytmiikkaan keskittyviä analyysimetodeja sovellettaessa musiikkia tarkastellaan tietystä esityksestä tehdyn nuottiesityksen, transkription välityksellä. Hienorytmisiä analyysimetodeja käytettäessä musiikkia tarkastellaan esitysten instrumenttiosuuksien sävelten alukehetkien tarkkojen sijaintien kautta. Alukehetket poimitaan erilaisin automaattisin ja manuaalisin tietokoneavusteisin menetelmin äänitteiltä. Tutkimuksessa tarkastellaan musiikissa esiintyviä ilmiöitä myös laajemmalla, musiikin havaitsemiseen ja tuottamiseen yleisesti liittyvällä musiikkikognition tasolla. Tärkeänä näkökulmana musiikin rytmiikan esitetään jakautuvan kognitiivisesti karkeampaan tekstuaaliseen rytmiikkaan ja tätä hienoisesti varioivaan ei-tekstuaaliseen hienorytmiikkaan. Analyysiosuudessa kehitettyjä metodeja sovelletaan seuraavien kappaleiden soolo-osuuksiin: Miles Davis – 'Freddie Freeloader' (1959), James Brown – 'Doing it to Death' (1973) ja Led Zeppelin – 'Stairway to Heaven' (1971). Kappaleet edustavat tutkimuksessa jazz-, funk- ja rock-tyylilajeja. Analyysi tarkastelee ja vertailee kappaleiden metristä stabiiliutta, instrumenttiosuuksien suhdetta pulssin iskuihin, rytmiikan kolmimuunteisuutta, soolojen metrisiä painopisteitä, soolojen rytmistä tiheyttä sekä tempojen muutoksia. -- Kehitetyt menetelmät osoittautuvat kaikki käyttökelpoisiksi. Kappaleille yhteiseksi piirteeksi paljastuu instrumenttiosuuksien säännönmukainen sijoittuminen pulssin iskuihin nähden kappaleiden sisällä. Kappaleiden välillä eri instrumentit sijoittuvat kuitenkin pulssin ympärille eroavin tavoin, jonka oletetaan johtuvan ennen kaikkea tyylilajien eroista. Tempot pysyvät kappaleissa varsin muuttumattomina. Jatkotutkimuksen kannalta mielenkiintoisia näkymiä ovat muun muassa metodien laajempi soveltaminen, automaattisten menetelmien kehittäminen

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This study examined the nature and lifetime prevalence of two types of victimization among Finnish university students: stalking and violence victimization (i.e. general violence). This study was a cross-sectional study using two different datasets of Finnish university students. The stalking data was collected via an electronic questionnaire and the violence victimization data was collected via a postal questionnaire. There were 615 participants in the stalking study (I-III) and 905 participants in the violence victimization study. The thesis consists of four studies. The aims regarding the stalking substudies (Studies I-III) were to examine the lifetime prevalence of stalking among university students and to analyze how stalking is related to victim and stalker characteristics and certain central variables of stalking (victim-stalker relationship, stalking episodes, stalking duration). Specifically, the aim was to identify factors that are associated with stalking violence and to factors contributing to the stalking duration. Furthermore, the aim was also to investigate how university students cope with stalking and whether coping is related to victim and stalker background characteristics and to certain other core variables (victim-stalker relationship, stalking episodes, stalking duration, prior victimization, and stalking violence). The aims for the violence victimization substudy (Study IV) were to examine the prevalence of violence victimization, i.e. general violence (minor and serious physical violence and threats) and how violence victimization is associated with victim/abuser characteristics, symptomology, and the use of student health care services. The present study shows that both stalking and violence victimization (i.e. general violence) are markedly prevalent among Finnish university students. The lifetime prevalence rate for stalking was 48.5% and 46.5% for violence victimization. When the lifetime prevalence rate was restricted to violent stalking and physical violence only, the prevalence decreased to 22% and 42% respectively. The students reported exposure to multiple forms of stalking and violence victimization, demonstrating the diversity of victimization among university students. Stalking victimization was found to be more prevalent among female students, while violence victimization was found to be more prevalent among male students. Most of the victims of stalking knew their stalkers, while the offender in general violence was typically a stranger. Stalking victimization often included violence and continued for a lengthy period. The victim-stalking relationship and stalking behaviors were found to be associated with stalking violence and stalking duration. Based on three identified stalking dimensions (violence, surveillance, contact seeking), the present study found five distinct victim subgroups (classes). Along with the victim-stalker relationship, the victim subgroups emerged as important factors contributing to the stalking duration. Victims of violent stalking did not differ greatly from victims of non-violent stalking in their use of behavioral coping tactics, while exposure to violent stalking had an effect on the use of coping strategies. The victim-offender relationship was also associated to a set of symptoms regarding violence victimization. Furthermore, violence victimization had a significant main effect on specific symptoms (mental health symptoms, alcohol consumption, symptom index), while gender had a significant main effect on most symptoms, yet no interaction effect was found. The present results also show that victims of violence are overrepresented among frequent health care users. The present findings add to the literature on the prevalence and nature of stalking and violence victimization among Finnish university students. Moreover, the present findings stress the importance of violence prevention and intervention in student health care, and may be used as a guideline for policy makers, as well as health care and law enforcement professionals dealing with youth violence prevention.

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The aim of this dissertation was to explore how different types of prior knowledge influence student achievement and how different assessment methods influence the observed effect of prior knowledge. The project started by creating a model of prior knowledge which was tested in various science disciplines. Study I explored the contribution of different components of prior knowledge on student achievement in two different mathematics courses. The results showed that the procedural knowledge components which require higher-order cognitive skills predicted the final grades best and were also highly related to previous study success. The same pattern regarding the influence of prior knowledge was also seen in Study III which was a longitudinal study of the accumulation of prior knowledge in the context of pharmacy. The study analysed how prior knowledge from previous courses was related to student achievement in the target course. The results implied that students who possessed higher-level prior knowledge, that is, procedural knowledge, from previous courses also obtained higher grades in the more advanced target course. Study IV explored the impact of different types of prior knowledge on students’ readiness to drop out from the course, on the pace of completing the course and on the final grade. The study was conducted in the context of chemistry. The results revealed again that students who performed well in the procedural prior-knowledge tasks were also likely to complete the course in pre-scheduled time and get higher final grades. On the other hand, students whose performance was weak in the procedural prior-knowledge tasks were more likely to drop out or take a longer time to complete the course. Study II explored the issue of prior knowledge from another perspective. Study II aimed to analyse the interrelations between academic self-beliefs, prior knowledge and student achievement in the context of mathematics. The results revealed that prior knowledge was more predictive of student achievement than were other variables included in the study. Self-beliefs were also strongly related to student achievement, but the predictive power of prior knowledge overruled the influence of self-beliefs when they were included in the same model. There was also a strong correlation between academic self-beliefs and prior-knowledge performance. The results of all the four studies were consistent with each other indicating that the model of prior knowledge may be used as a potential tool for prior knowledge assessment. It is useful to make a distinction between different types of prior knowledge in assessment since the type of prior knowledge students possess appears to make a difference. The results implied that there indeed is variation between students’ prior knowledge and academic self-beliefs which influences student achievement. This should be taken into account in instruction.

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Objectives. The purpose of this study was to examine perceptions of evaluation of learning and feedback among teachers and students of mechanical engineering at the Helsinki University of Technology. The differences and similarities between the perceptions of these two groups were also studied. Course feedback was examined, and a target was set to rationalize the collation and exploitation of the feedback data. The theoretical background for the evaluation of learning was based primarily on the theories of Brown (1997), Karjalainen (2001) and Rowntree (1977, 1988). The Biggs (2003) model on aligned teaching was used as an example of quality university education. Feedback practices were examined through the theory of Ramsden (1992) and many recent research articles. Methods. The qualitative study was executed by examining the evaluation of learning and feedback prac-tices of the courses in mechanical engineering at the Helsinki University of Technology. The data was gathered by interviewing the teachers responsible of basic and postgraduate studies, as well as students taking their basic studies. Four group interviews were arranged for both teachers and students, each with three participants. The data from these themed interviews were analyzed by means of content analysis. Result and conclusions. This study showed that teachers and students have similar perceptions of evalua-tion of learning and feedback excluding a few significant differences. The most essential difference in evaluation of learning was that students perceived the evaluation of the examinations to be inaccurate. Teachers on the other hand thought that the existing practice for the exam evaluation is working fine. Stu-dents also felt that they are not giving enough information on the opportunities to get feedback. Teachers instead expected students to actively ask for feedback. Students perceived the need for exploiting the course feedback for course development purposes more than before. Teachers saw foremost the challenges and problems in the exploitation of the feedback. In the future, more effort must be put on the research of the evaluation of learning and feedback, as the quality assurance and continuous improvement of the teaching calls for new data.

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Knowledge of the habitat requirements of bat species is needed in decision making in land use planning. Bats' hibernation requirements were studied both in Estonia and in southern Finland. In both countries, the northern bat and the brown long-eared bat hibernated in colder and drier locations, whereas Daubenton's bat and Brandt's/whiskered bats hibernated in warmer and more humid locations. In Estonia, the pond bat hibernated in the warmest and most humid conditions, whereas Natterer's bat hibernated in the coldest and driest conditions. Hibernacula were at their coldest in mid-season and became warmer towards the end of the season. The results suggest that bats made an active choice of colder hibernation temperatures at the seasons end. They minimised the negative effects of hibernation early in the hibernation season by hibernating in warmer locations and energy expenditure late in the hibernation season by hibernating in colder locations. The use of foraging habitats was studied in northern and southern Finland. The northern bat used foraging sites opportunistically. Daubenton's bat foraged mainly in water habitats, whereas Brandt's/whiskered bats and the brown long-eared bat foraged mainly in forest habitats. In northern Finland, Daubenton's bats foraged almost exclusively on rivers and typically together with the northern bat. Daubenton's bats and Brandt's/whiskered bats were found only where there were lower ambient light levels. One of the most important things in the management of foraging areas for them is to keep them shady. Hibernacula in Finland typically housed few bats, suggesting that hibernation sites used by even a small number of bats are important. Bats typically used natural stone for hibernation suggesting that natural underground sites in rocks or cliffs or man-made underground sites built using natural stone are important for them. The results suggest that appropriate timing of surveys may vary according to the species and latitude.

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Rhizoctonia solani is a soil inhabiting basidiomycetous fungus able to induce a wide range of symptoms in many plant species. This genetically complex species is divided to 13 anastomosis groups (AG), of which AG-3 is specialized to infect potato. However, also a few other AGs are able to infect or live in close contact with potato. On potato, R. solani infection causes two main types of diseases including stem canker observed as a dark brown lesions on developing stems and stolons, and black scurf that develops on new tubers close to the time of harvest. These disease symptoms are collectively called a ‘Rhizoctonia disease complex’. Between the growing seasons R. solani survives in soil and plant debri as sclerotia or as the sclerotia called black scurf on potato tubers which when used as seed offer the main route for dispersal of the fungus to new areas. The reasons for the dominance of AG-3 on potato seem to be attributable to its highly specialization to potato and its ability to infect and form sclerotia efficiently at low temperatures. In this study, a large nationwide survey of R. solani isolates was made in potato crops in Finland. Almost all characterized isolates belonged to AG-3. Additionally, three other AGs (AG-2-1, AG-4 and AG-5) were found associated with symptoms on potato plants but they were weaker pathogens on potato than AG-3 as less prone to form black scurf. According to phylogenetic analysis of the internal transcribed sequences (ITS) of the ribosomal RNA genes the Finnish AG-3 isolates are closely related to each other even though a wide variation of physiological features was observed between them. Detailed analysis of the ITS regions revealed single nucleotide polymorphism in 14 nucleotide positions of ITS-1 and ITS-2. Additionally, compensatory base changes on ITS-2 were detected which suggests that potato-infecting R. solani AG-3 could be considered as a separate species instead of an AG of R. solani. For the first time, molecular defence responses were studied and detected during the early phases of interaction between R. solani AG-3 and potato. Extensive systemic signalling for defence exploiting several known defence pathways was activated as soon as R. solani came into close contact with the base of a sprout. The defence response was strong enough to protect vulnerable sprout tips from new attacks by the pathogen. These results at least partly explain why potato emergence is eventually successful even under heavy infection pressure by R. solani.

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Valko- ja ruskolahosienet tunnetaan luonnossa tehokkaimpina puun ja karikkeen lignoselluloosan lahottajina. Valkolahosienet pystyvät hajottamaan kaikkia puun osia: ligniiniä, selluloosaa ja hemiselluloosaa. Selektiivisesti ligniiniä hajottavat sienet lahottavat puusta suhteessa enemmän vaikeasti hajoavaa ligniiniä kuin selluloosaa tai hemiselluloosaa, jolloin jäljelle jää valkoista ja miltei puhdasta selluloosaa. Bioteknisissä sovelluksissa juuri selektiviiviset valkolahottajat ovat kiinnostavia. Niiden avulla voidaan puuhaketta esikäsitellä esimerkiksi paperinvalmistuksessa haitallisen ligniinin poistamiseksi. Ruskolahosienet ovat huomattavia puun, puutavaran ja puisten rakenteiden lahottajia, kuten tässä työssä käytetty Gloeophyllum trabeum (saunasieni ) ja Poria (Postia) placenta (istukkakääpä). Ruskolahosienet hajottavat puusta hemiselluloosan lisäksi selluloosaa, jolloin jää jäljelle ruskea ja jauhomaiseksi mureneva ligniini. Ruskolahosienet muovaavat ligniiniä jonkin verran. Kahden ruskolahosienen G. trabeumin ja P. placentan lisäksi tutkittiin valkolahosieniä, joista Ceriporiopsis subvermispora (karstakääpä) ja harvinainen Physisporinus rivulosus -sieni (talikääpä) hajottavat ligniiniä erittäin selektiivisesti. Phanerochaete chrysosporium on kaikkialla paljon tutkittu sieni, ja Phlebia radiata valkolahosientä (rusorypykkä) on tutkittu paljon mikrobiologian osastolla. Lisäksi tutkittiin Phlebia tremellosa -sienten (hytyrypykkä) ligninolyyttisten entsyymien tuottoa ja 14C-leimatun synteettisen ligniinin (DHP) hajotusta. P. radiata ja P. tremellosa -sienten on todettu aiemmin hajottavan ligniiniä selektiivisesti. Työssä selvitettiin miten sienten kasvua voi mitata, miten vertailukelpoisia eri mittaamismenetelmillä saadut tulokset ovat ja ilmenevätkö sienten aktiivisimmat kasvuvaiheet samaan aikaan eri menetelmillä mitattuna. Tärkeimmät tulokset olivat seuraavat havainnot: (i) P. radiata ja P. tremellosa -sienikannat tuottivat ligniini- ja mangaaniperoksidaasientsyymejä (LiP ja MnP) sekä lakkaasia, ja sienistä puhdistettiin 2-3 LiP- ja P. radiatasta yksi MnP-entsyymi; (ii) P. tremellosa -sienet hajottivat leimattua synteettistä ligniiniä (DHP) yhtä hyvin kuin paljon tutkitut P. chrysosporium ja P. radiata -sienet; (iii) puu, sienen luonnollinen kasvualusta, lisäsi valkolaho- ja ruskolahosienten demetoksylaatiota [O14CH3]-leimatusta ligniinin malliyhdisteestä 14CO2:ksi ilman puuta olleeseen alustaan verrattuna; (iv) demetoksylaatio (14CO2:n tuotto) oli normaalissa ilma-atmosfäärissä useimmiten parempi happeen verrattuna; (v) hapessa paras 14CO2:n tuotto saatiin puupalakasvatuksissa, joihin oli lisätty ravinnetyppeä tai typen lisäksi glukoosia sekä valkolaho- että ruskolahosienillä; (vi) ilmassa 14CO2:n tuotto oli puulla voimakkainta valkolahosienillä ilman lisäravinteita, kun taas G. trabeum -sienellä se oli yhtä hyvä eri alustoissa; (vii) biomassan muodostuminen rihmastojen ergosterolipitoisuuksista mitattuna oli ruskolahosienillä parempi kuin valkolahosienillä; (viii) ja biomassojen huippupitoisuudet olivat 6:lla sienellä eri suuruisia ja niiden maksimimäärien ajankohdat vaihtelivat viiden viikon kasvatusten kuluessa. Mikrobiologian osastolla Viikissä eristetty ja paljon tutkittu P. radiata -valkolahosieni oli mukana kaikissa tehdyissä kokeissa. Sienen LiP-aktiivisuus ja 14CO2:n tuotto 14C-rengas-leimatusta synteettisestä ligniinistä (DHP) korreloivat erittäin hyvin. Biomassan muodostuminen ergosterolilla määritettynä tuki hyvin entsyymiaktiivisuusmittauksilla ja isotooppikasvatuksilla saatuja tuloksia.

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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.