44 resultados para depth-first
em Helda - Digital Repository of University of Helsinki
Resumo:
Raportissa on arvioitu ilmastonmuutoksen vaikutusta Suomen maaperän talviaikaiseen jäätymiseen lämpösummien perusteella. Laskelmat kuvaavat roudan paksuutta nimenomaisesti lumettomilla alueilla, esimerkiksi teillä, joilta satanut lumi aurataan pois. Luonnossa lämpöä eristävän lumipeitteen alla routaa on ohuemmin kuin tällaisilla lumettomilla alueilla. Toisaalta luonnollisessa ympäristössä paikalliset erot korostuvat johtuen mm. maalajeista ja kasvillisuudesta. Roudan paksuudet laskettiin ensin perusjakson 1971–2000 ilmasto-oloissa talviaikaisten säähavaintotietoihin pohjautuvien lämpötilojen perusteella. Sen jälkeen laskelmat toistettiin kolmelle tulevalle ajanjaksolle (2010–2039, 2040–2069 ja 2070–2099) kohottamalla lämpötiloja ilmastonmuutosmallien ennustamalla tavalla. Laskelman pohjana käytettiin 19 ilmastomallin A1B-skenaarioajojen keskimäärin simuloimaa lämpötilan muutosta. Tulosten herkkyyden arvioimiseksi joitakin laskelmia tehtiin myös tätä selvästi heikompaa ja voimakkaampaa lämpenemisarviota käyttäen. A1B-skenaarion mukaisen lämpötilan nousun toteutuessa nykyisiä mallituloksia vastaavasti routakerros ohenee sadan vuoden aikana Pohjois-Suomessa 30–40 %, suuressa osassa maan keski- ja eteläosissa 50–70 %. Jo lähivuosikymmeninä roudan ennustetaan ohentuvan 10–30 %, saaristossa enemmän. Mikäli lämpeneminen toteutuisi voimakkaimman tarkastellun vaihtoehdon mukaisesti, roudan syvyys pienenisi tätäkin enemmän. Roudan paksuuden vuosienvälistä vaihtelua ja sen muuttumista tulevaisuudessa pyrittiin myös arvioimaan. Leutoina talvina routa ohenee enemmän kuin normaaleina tai ankarina pakkastalvina. Päivittäistä sään vaihtelua simuloineen säägeneraattorin tuottamassa aineistoissa esiintyi kuitenkin liian vähän hyvin alhaisia ja hyvin korkeita lämpötiloja. Siksi näitten lämpötilatietojen pohjalta laskettu roudan paksuuskin ilmeisesti vaihtelee liian vähän vuodesta toiseen. Kelirikkotilanteita voi esiintyä myös kesken routakauden, jos useamman päivän suojasää ja samanaikainen runsas vesisade pääsevät sulattamaan maata. Tällaiset routakauden aikana sattuvat säätilat näyttävätkin yleistyvän lähivuosikymmeninä. Vuosisadan loppua kohti ne sen sijaan maan eteläosissa jälleen vähenevät, koska routakausi lyhenee oleellisesti. Tulevia vuosikymmeniä koskevien ilmastonmuutosennusteiden ohella routaa ja kelirikon esiintymistä on periaatteessa mahdollista ennustaa myös lähiaikojen sääennusteita hyödyntäen. Pitkät, viikkojen tai kuukausien mittaiset sääennusteet eivät tosin ole ainakaan vielä erityisen luotettavia, mutta myös lyhyemmistä ennusteista voisi olla hyötyä mm. tienpitoa suunniteltaessa.
Resumo:
This dissertation is a theoretical study of finite-state based grammars used in natural language processing. The study is concerned with certain varieties of finite-state intersection grammars (FSIG) whose parsers define regular relations between surface strings and annotated surface strings. The study focuses on the following three aspects of FSIGs: (i) Computational complexity of grammars under limiting parameters In the study, the computational complexity in practical natural language processing is approached through performance-motivated parameters on structural complexity. Each parameter splits some grammars in the Chomsky hierarchy into an infinite set of subset approximations. When the approximations are regular, they seem to fall into the logarithmic-time hierarchyand the dot-depth hierarchy of star-free regular languages. This theoretical result is important and possibly relevant to grammar induction. (ii) Linguistically applicable structural representations Related to the linguistically applicable representations of syntactic entities, the study contains new bracketing schemes that cope with dependency links, left- and right branching, crossing dependencies and spurious ambiguity. New grammar representations that resemble the Chomsky-Schützenberger representation of context-free languages are presented in the study, and they include, in particular, representations for mildly context-sensitive non-projective dependency grammars whose performance-motivated approximations are linear time parseable. (iii) Compilation and simplification of linguistic constraints Efficient compilation methods for certain regular operations such as generalized restriction are presented. These include an elegant algorithm that has already been adopted as the approach in a proprietary finite-state tool. In addition to the compilation methods, an approach to on-the-fly simplifications of finite-state representations for parse forests is sketched. These findings are tightly coupled with each other under the theme of locality. I argue that the findings help us to develop better, linguistically oriented formalisms for finite-state parsing and to develop more efficient parsers for natural language processing. Avainsanat: syntactic parsing, finite-state automata, dependency grammar, first-order logic, linguistic performance, star-free regular approximations, mildly context-sensitive grammars
Resumo:
The study proposes a method for identifying the personal imprint of literary translators in translated works of fiction. The initial assumption was that the style of a target text is not determined solely by the literary style of the author but also by features of its translator s idiolect. A method was developed for identifying the idiolectal features of individual translators, which were then used to describe personal translation styles. The method is not restricted to a particular language pair. To test the method and to establish the nature of the proposed personal imprint empirically, extracts from four English-language literary source texts (two novels by James Joyce and two by Ernest Hemingway) were first compared with their translations into Finnish (by four different translators) in order to identify changes, or shifts, that had taken place at the formal linguistic level in the translation process. To allow individual propensities to manifest themselves, only optional shifts in which the translators had a range of choices available to them were included in the study. In the second phase, extracts by different authors rendered into Finnish by the same translator were compared in order to gauge the extent of the potential impact of the author's style on the translator's work. In-depth analysis of the types of shifts made most frequently by the individual translators revealed further intersubjective differences, and the shifts were used to construct translation profiles for each of the translators. In order to determine the potential effects of frequently occurring shifts on the target text, some central concepts of narratology were adapted and used to establish an intermediate link between microlevel choices and macrolevel effects. In this way the propensity of an individual translator to opt for certain types of shift could be linked with the overall artistic effect of the target text.
Resumo:
The dissertation presents a functional model for analysis of song translation. The model is developed on the basis of an examination of theatrical songs and a comparison of three translations: the songs of the Broadway musical My Fair Lady (Lerner and Loewe, 1956), made for the premiere productions (1959–1960) in Swedish, Danish, and Norwegian. The analysis explores the three challenges of a song translator: the fitting of a text to existing music, the consideration of a prospective sung performance, and the verbal approximation of the content of the source lyric. The theoretical foundation is based on a functional approach to translation studies (Christiane Nord) and a structuralist/semiotic analysis of a theatrical message (Ivo Osolsobě, building on Roman Jakobson). Thus, three functional levels in the fitting of a text to music are explored: first, a prosodic/phonetic format; secondly, a poetic/rhetoric format; and thirdly, semantic/reflexive values (verbalizing musical expression). Similarly, three functional levels in the textual connections to a prospective performance are explored: first, a presentational goal; secondly, the theatrical potential; and thirdly, dramaturgic values (for example dramatic information and linguistic register). The functionality of Broadway musical theatre songs is analyzed, and the song score of My Fair Lady, source and target lyrics, is studied, with an in-depth analysis of seven of the songs. The three translations were all considered very well-made and are used in productions of the musical to this day. The study finds that the song translators appear to have worked from an understanding of the presentational goal, designed their target texts on the prosodic and poetic shape of the music, and pursued the theatrical functionality of the song, not by copying, but by recreating connections to relevant contexts, partly independently of the source lyrics, using the resources of the target languages. Besides metaphrases (closest possible transfer), paraphrases and additions seem normally to be expected in song translation, but song translators may also follow highly individual strategies – for example, the Norwegian translator is consistently more verbally faithful than the Danish and Swedish translators. As a conclusion, it is suggested that although linguistic and cultural difference play a significant role, a translator’s solution must nevertheless be arrived at, and assessed, in relation to the song as a multimedial piece of material. As far as a song can be considered a theatrical message – singers representing the voice, person, and situation of the song – the descriptive model presented in the study is also applicable to the translation of other types of song.
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This study aims to examine the operations and significance of the Klemetti Institute (Klemetti-Opisto) as a developer of Finnish music culture from 1953 to 1968 during the term of office of the Institute s founder and first director, Arvo Vainio. The Klemetti Institute was originally established as a choir institute, but soon expanded to offer a wide range of music courses. In addition to providing courses for choir leaders and singers, the Institute began its orchestral activities as early as the mid-1950s. Other courses included ear training seminars as well as courses for young people s music instructors and in playing the kantele (a Finnish string instrument) and solo singing. More than 20 types of courses were offered over the 16-year period. The Klemetti Institute s courses were incorporated into the folk high school courses offered by the Orivesi Institute (Oriveden Opisto) and were organised during the summer months of June and July. In addition to funding based on the Folk High School Act, financial assistance was obtained from various foundations and funds, such as the Wihuri Foundation. This study is linked to the context of historical research. I examine the Klemetti Institute s operations chronologically, classifying instruction into different course types, and analyse concert activities primarily in the section on the Institute s student union. The source material includes the Klemetti Institute archives, which consist of Arvo Vainio s correspondence, student applications, register books and cards, journals and student lists, course albums and nearly all issues of the Klemettiläinen bulletin. In addition, I have used focused interviews and essays to obtain extensive data from students and teachers. I concentrate on primary school teachers, who accounted for the majority of course participants. A total of more than 2,300 people participated in the courses, nearly half of whom took courses during at least two summers. Primary school teachers accounted for 50% to 70% of the participants in most courses and constituted an even larger share of participants in some courses, such as the music instructor course. The Klemetti Institute contributed to the expansion throughout Finland of a new ideal for choral tone. This involved delicate singing which strives for tonal purity and expressiveness. Chamber choirs had been virtually unheard of in Finland, but the Klemetti Institute Chamber Choir popularised them. Chamber choirs are characterised by an extensive singing repertoire ranging from the Middle Ages to the present. As the name suggests, chamber choirs were originally rather small mixed choirs. Delicate singing meant the avoidance of extensive vibrato techniques and strong, heavy forte sounds, which had previously been typical of Finnish choirs. Those opposing and shunning this new manner of singing called it ghost singing . The Klemetti Institute s teachers included Finland s most prominent pedagogues and artists. As the focused essays, or reminiscences as I call them, show, their significance for the students was central. I examine extensively the Klemetti Institute s enthusiastic atmosphere, which during the early years was characterised by what some writers described as a hunger for music . In addition to distributing a new tonal ideal and choir repertoire, the Klemetti Institute also distributed new methods of music education, thus affecting the music teaching of Finnish primary schools, in particular. The Orff approach, which included various instruments, became well known, although some of Orff s ideas, such as improvisation and physical exercise, were initially unfamiliar. More important than the Orff approach was the in-depth teaching at the Klemetti Institute of the Hungarian ear training method known as the Kodály method. Many course participants were among those launching specialist music classes in schools, and the method became the foundation for music teaching in many such schools. The Klemetti Institute was also a pioneer in organising orchestra camps for young people. The Klemetti Institute promoted Finnish music culture and played an important role in the continuing music education of primary school teachers. Keywords: adult education, Grundtvigian philosophy, popular enlightenment, Klemetti Institute, Kodály method, choir singing, choir conducting, music history, music education, music culture, music camp, Orff approach, Orff-Schulwerk, Orivesi Institute, instrument teaching, free popular education, communality, solo singing, voice production
Resumo:
Sleep deprivation leads to increased subsequent sleep length and depth and to deficits in cognitive performance in humans. In animals extreme sleep deprivation is eventually fatal. The cellular and molecular mechanisms causing the symptoms of sleep deprivation are unclear. This thesis was inspired by the hypothesis that during wakefulness brain energy stores would be depleted, and they would be replenished during sleep. The aim of this thesis was to elucidate the energy metabolic processes taking place in the brain during sleep deprivation. Endogenous brain energy metabolite levels were assessed in vivo in rats and in humans in four separate studies (Studies I-IV). In the first part (Study I) the effects of local energy depletion on brain energy metabolism and sleep were studied in rats with the use of in vivo microdialysis combined with high performance liquid chromatography. Energy depletion induced by 2,4-dinitrophenol infusion into the basal forebrain was comparable to the effects of sleep deprivation: both increased extracellular concentrations of adenosine, lactate, and pyruvate, and elevated subsequent sleep. This result supports the hypothesis of a connection between brain energy metabolism and sleep. The second part involved healthy human subjects (Studies II-IV). Study II aimed to assess the feasibility of applying proton magnetic resonance spectroscopy (1H MRS) to study brain lactate levels during cognitive stimulation. Cognitive stimulation induced an increase in lactate levels in the left inferior frontal gyrus, showing that metabolic imaging of neuronal activity related to cognition is possible with 1H MRS. Study III examined the effects of sleep deprivation and aging on the brain lactate response to cognitive stimulation. No physiologic, cognitive stimulation-induced lactate response appeared in the sleep-deprived and in the aging subjects, which can be interpreted as a sign of malfunctioning of brain energy metabolism. This malfunctioning may contribute to the functional impairment of the frontal cortex both during aging and sleep deprivation. Finally (Study IV), 1H MRS major metabolite levels in the occipital cortex were assessed during sleep deprivation and during photic stimulation. N-acetyl-aspartate (NAA/H2O) decreased during sleep deprivation, supporting the hypothesis of sleep deprivation-induced disturbance in brain energy metabolism. Choline containing compounds (Cho/H2O) decreased during sleep deprivation and recovered to alert levels during photic stimulation, pointing towards changes in membrane metabolism, and giving support to earlier observations of altered brain response to stimulation during sleep deprivation. Based on these findings, it can be concluded that sleep deprivation alters brain energy metabolism. However, the effects of sleep deprivation on brain energy metabolism may vary from one brain area to another. Although an effect of sleep deprivation might not in all cases be detectable in the non-stimulated baseline state, a challenge imposed by cognitive or photic stimulation can reveal significant changes. It can be hypothesized that brain energy metabolism during sleep deprivation is more vulnerable than in the alert state. Changes in brain energy metabolism may participate in the homeostatic regulation of sleep and contribute to the deficits in cognitive performance during sleep deprivation.
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Puumala virus (PUUV) is the causative agent of nephropathia epidemica (NE), a mild form of hemorrhagic fever with renal syndrome. Finland has the highest documented incidence of NE with around 1000 cases diagnosed annually. PUUV is also found in other Scandinavian countries, Central Europe and the European part of Russia. PUUV belongs to the genus Hantavirus in the family Bunyaviridae. Hantaviruses are rodent-borne viruses each carried by a specific host that is persistently and asymptomatically infected by the virus. PUUV is carried by the bank voles (Myodes glareolus, previously known as Clethrionomys glareolus). Hantaviruses have co-evolved with their carrier rodents for millions of years and these host animals are the evolutionary scene of hantaviruses. In this study, PUUV sequences were recovered from bank voles captured in Denmark and Russian Karelia to study the evolution of PUUV in Scandinavia. Phylogenetic analysis of these strains showed a geographical clustering of genetic variants following the presumable migration pattern of bank voles during the recolonization of Scandinavia after the last ice age approximately 10 000 years ago. The currently known PUUV genome sequences were subjected to in-depth phylogenetic analyses and the results showed that genetic drift seems to be the major mechanism of PUUV evolution. In general, PUUV seems to evolve quite slowly following a molecular clock. We also found evidence for recombination in the evolution of some genetic lineages of PUUV. Viral microevolution was studied in controlled virus transmission in colonized bank voles and changes in quasispecies dynamics were recorded as the virus was transmitted from one animal to another. We witnessed PUUV evolution in vivo, as one synonymous mutation became repeatedly fixed in the viral genome during the experiment. The detailed knowledge on the PUUV diversity was used to establish new sensitive and specific detection methods for this virus. Direct viral invasion of the hypophysis was demonstrated for the first time in a lethal case of NE. PUUV detection was done by immunohistochemistry, in situ hybridization and RT-nested-PCR of the autopsy tissue samples.
Resumo:
Precipitation-induced runoff and leaching from milled peat mining mires by peat types: a comparative method for estimating the loading of water bodies during peat production. This research project in environmental geology has arisen out of an observed need to be able to predict more accurately the loading of watercourses with detrimental organic substances and nutrients from already existing and planned peat production areas, since the authorities capacity for insisting on such predictions covering the whole duration of peat production in connection with evaluations of environmental impact is at present highly limited. National and international decisions regarding monitoring of the condition of watercourses and their improvement and restoration require more sophisticated evaluation methods in order to be able to forecast watercourse loading and its environmental impacts at the stage of land-use planning and preparations for peat production.The present project thus set out from the premise that it would be possible on the basis of existing mire and peat data properties to construct estimates for the typical loading from production mires over the whole duration of their exploitation. Finland has some 10 million hectares of peatland, accounting for almost a third of its total area. Macroclimatic conditions have varied in the course of the Holocene growth and development of this peatland, and with them the habitats of the peat-forming plants. Temperatures and moisture conditions have played a significant role in determining the dominant species of mire plants growing there at any particular time, the resulting mire types and the accumulation and deposition of plant remains to form the peat. The above climatic, environmental and mire development factors, together with ditching, have contributed, and continue to contribute, to the existence of peat horizons that differ in their physical and chemical properties, leading to differences in material transport between peatlands in a natural state and mires that have been ditched or prepared for forestry and peat production. Watercourse loading from the ditching of mires or their use for peat production can have detrimental effects on river and lake environments and their recreational use, especially where oxygen-consuming organic solids and soluble organic substances and nutrients are concerned. It has not previously been possible, however, to estimate in advance the watercourse loading likely to arise from ditching and peat production on the basis of the characteristics of the peat in a mire, although earlier observations have indicated that watercourse loading from peat production can vary greatly and it has been suggested that differences in peat properties may be of significance in this. Sprinkling is used here in combination with simulations of conditions in a milled peat production area to determine the influence of the physical and chemical properties of milled peats in production mires on surface runoff into the drainage ditches and the concentrations of material in the runoff water. Sprinkling and extraction experiments were carried out on 25 samples of milled Carex (C) and Sphagnum (S) peat of humification grades H 2.5 8.5 with moisture content in the range 23.4 89% on commencement of the first sprinkling, which was followed by a second sprinkling 24 hours later. The water retention capacity of the peat was best, and surface runoff lowest, with Sphagnum and Carex peat samples of humification grades H 2.5 6 in the moisture content class 56 75%. On account of the hydrophobicity of dry peat, runoff increased in a fairly regular manner with drying of the sample from 55% to 24 30%. Runoff from the samples with an original moisture content over 55% increased by 63% in the second round of sprinkling relative to the first, as they had practically reached saturation point on the first occasion, while those with an original moisture content below 55% retained their high runoff in the second round, due to continued hydrophobicity. The well-humified samples (H 6.5 8.5) with a moisture content over 80% showed a low water retention capacity and high runoff in both rounds of sprinkling. Loading of the runoff water with suspended solids, total phosphorus and total nitrogen, and also the chemical oxygen demand (CODMn O2), varied greatly in the sprinkling experiment, depending on the peat type and degree of humification, but concentrations of the same substances in the two sprinklings were closely or moderately closely correlated and these correlations were significant. The concentrations of suspended solids in the runoff water observed in the simulations of a peat production area and the direct surface runoff from it into the drainage ditch system in response to rain (sprinkling intensity 1.27 mm/min) varied c. 60-fold between the degrees of humification in the case of the Carex peats and c. 150-fold for the Sphagnum peats, while chemical oxygen demand varied c. 30-fold and c. 50-fold, respectively, total phosphorus c. 60-fold and c. 66-fold, total nitrogen c. 65-fold and c. 195-fold and ammonium nitrogen c. 90-fold and c. 30-fold. The increases in concentrations in the runoff water were very closely correlated with increases in humification of the peat. The correlations of the concentrations measured in extraction experiments (48 h) with peat type and degree of humification corresponded to those observed in the sprinkler experiments. The resulting figures for the surface runoff from a peat production area into the drainage ditches simulated by means of sprinkling and material concentrations in the runoff water were combined with statistics on the mean extent of daily rainfall (0 67 mm) during the frost-free period of the year (May October) over an observation period of 30 years to yield typical annual loading figures (kg/ha) for suspended solids (SS), chemical oxygen demand of organic matter (CODmn O2), total phosphorus (tot. P) and total nitrogen (tot. N) entering the ditches with respect to milled Carex (C) and Sphagnum (S) peats of humification grades H 2.5 8.5. In order to calculate the loading of drainage ditches from a milled peat production mire with the aid of these annual comparative values (in kg/ha), information is required on the properties of the intended production mire and its peat. Once data are available on the area of the mire, its peat depth, peat types and their degrees of humification, dry matter content, calorific value and corresponding energy content, it is possible to produce mutually comparable estimates for individual mires with respect to the annual loading of the drainage ditch system and the surrounding watercourse for the whole service life of the production area, the duration of this service life, determinations of energy content and the amount of loading per unit of energy generated (kg/MWh). In the 8 mires in the Köyhäjoki basin, Central Ostrobothnia, taken as an example, the loading of suspended solids (SS) in the drainage ditch networks calculated on the basis of the typical values obtained here and existing mire and peat data and expressed per unit of energy generated varied between the mires and horizons in the range 0.9 16.5 kg/MWh. One of the aims of this work was to develop means of making better use of existing mire and peat data and the results of corings and other field investigations. In this respect combination of the typical loading values (kg/ha) obtained here for S, SC, CS and C peats and the various degrees of humification (H 2.5 8.5) with the above mire and peat data by means of a computer program for the acquisition and handling of such data would enable all the information currently available and that deposited in the system in the future to be used for defining watercourse loading estimates for mires and comparing them with the corresponding estimates of energy content. The intention behind this work has been to respond to the challenge facing the energy generation industry to find larger peat production areas that exert less loading on the environment and to that facing the environmental authorities to improve the means available for estimating watercourse loading from peat production and its environmental impacts in advance. The results conform well to the initial hypothesis and to the goals laid down for the research and should enable watercourse loading from existing and planned peat production to be evaluated better in the future and the resulting impacts to be taken into account when planning land use and energy generation. The advance loading information available in this way would be of value in the selection of individual peat production areas, the planning of their exploitation, the introduction of water protection measures and the planning of loading inspections, in order to achieve controlled peat production that pays due attention to environmental considerations.
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Frictions are factors that hinder trading of securities in financial markets. Typical frictions include limited market depth, transaction costs, lack of infinite divisibility of securities, and taxes. Conventional models used in mathematical finance often gloss over these issues, which affect almost all financial markets, by arguing that the impact of frictions is negligible and, consequently, the frictionless models are valid approximations. This dissertation consists of three research papers, which are related to the study of the validity of such approximations in two distinct modeling problems. Models of price dynamics that are based on diffusion processes, i.e., continuous strong Markov processes, are widely used in the frictionless scenario. The first paper establishes that diffusion models can indeed be understood as approximations of price dynamics in markets with frictions. This is achieved by introducing an agent-based model of a financial market where finitely many agents trade a financial security, the price of which evolves according to price impacts generated by trades. It is shown that, if the number of agents is large, then under certain assumptions the price process of security, which is a pure-jump process, can be approximated by a one-dimensional diffusion process. In a slightly extended model, in which agents may exhibit herd behavior, the approximating diffusion model turns out to be a stochastic volatility model. Finally, it is shown that when agents' tendency to herd is strong, logarithmic returns in the approximating stochastic volatility model are heavy-tailed. The remaining papers are related to no-arbitrage criteria and superhedging in continuous-time option pricing models under small-transaction-cost asymptotics. Guasoni, Rásonyi, and Schachermayer have recently shown that, in such a setting, any financial security admits no arbitrage opportunities and there exist no feasible superhedging strategies for European call and put options written on it, as long as its price process is continuous and has the so-called conditional full support (CFS) property. Motivated by this result, CFS is established for certain stochastic integrals and a subclass of Brownian semistationary processes in the two papers. As a consequence, a wide range of possibly non-Markovian local and stochastic volatility models have the CFS property.
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The main objective of the study is to evaluate the Finnish central government s foreign borrowing between the years 1862 and 1938. Most of this period was characterised by deep capital market integration that bears resemblance to the liberal world financial order at the turn of the millennium. The main aim is to analyse the credit risk associated with the state and its determination by evaluating the world financial market centres perception of Finland. By doing this, the study is also expected to provide an additional dimension to Finland s political and economic history by incorporating into the research the assessments of international capital markets regarding Finland during a period that witnessed profound political and economic changes in Finnish society. The evaluation of the credit risk mainly relies on exchange-rate risk free time series of the state s foreign bonds. They have been collected from quotations in the stock exchanges in Helsinki, Hamburg, Paris and London. In addition, it investigates Finland s exposure to short-term debt and Moody s credit ratings assigned to Finland. The study emphasises the importance of the political risk. It suggests that the hey-day of the state s reliance on foreign capital markets took place during last few decades of the 19th century when Finland enjoyed a wide autonomy in the Russian Empire and prudently managed its economy, highlighted in Finland s adherence to the international gold standard. Political confrontations in Finland and, in particular, in Russia and the turbulence of the world financial system prevented the return of this beneficial position again. Through its issuance of foreign bonds the state was able to import substantial amounts of foreign capital, which was sorely needed to foster economic development in Finland. Moreover, the study argues that the state s presence in the western capital markets not only had economic benefits, but it also increased the international awareness of Finland s distinct and separate status in the Russian Empire and later underlined its position as an independent republic.
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The tackling of coastal eutrophication requires water protection measures based on status assessments of water quality. The main purpose of this thesis was to evaluate whether it is possible both scientifically and within the terms of the European Union Water Framework Directive (WFD) to assess the status of coastal marine waters reliably by using phytoplankton biomass (ww) and chlorophyll a (Chl) as indicators of eutrophication in Finnish coastal waters. Empirical approaches were used to study whether the criteria, established for determining an indicator, are fulfilled. The first criterion (i) was that an indicator should respond to anthropogenic stresses in a predictable manner and has low variability in its response. Summertime Chl could be predicted accurately by nutrient concentrations, but not from the external annual loads alone, because of the rapid affect of primary production and sedimentation close to the loading sources in summer. The most accurate predictions were achieved in the Archipelago Sea, where total phosphorus (TP) and total nitrogen (TN) alone accounted for 87% and 78% of the variation in Chl, respectively. In river estuaries, the TP mass-balance regression model predicted Chl most accurately when nutrients originated from point-sources, whereas land-use regression models were most accurate in cases when nutrients originated mainly from diffuse sources. The inclusion of morphometry (e.g. mean depth) into nutrient models improved accuracy of the predictions. The second criterion (ii) was associated with the WFD. It requires that an indicator should have type-specific reference conditions, which are defined as "conditions where the values of the biological quality elements are at high ecological status". In establishing reference conditions, the empirical approach could only be used in the outer coastal water types, where historical observations of Secchi depth of the early 1900s are available. The most accurate prediction was achieved in the Quark. In the inner coastal water types, reference Chl, estimated from present monitoring data, are imprecise - not only because of the less accurate estimation method but also because the intrinsic characteristics, described for instance by morphometry, vary considerably inside these extensive inner coastal types. As for phytoplankton biomass, the reference values were less accurate than in the case of Chl, because it was possible to estimate reference conditions for biomass only by using the reconstructed Chl values, not the historical Secchi observations. An paleoecological approach was also applied to estimate annual average reference conditions for Chl. In Laajalahti, an urban embayment off Helsinki, strongly loaded by municipal waste waters in the 1960s and 1970s, reference conditions prevailed in the mid- and late 1800s. The recovery of the bay from pollution has been delayed as a consequence of benthic release of nutrients. Laajalahti will probably not achieve the good quality objectives of the WFD on time. The third criterion (iii) was associated with coastal management including the resources it has available. Analyses of Chl are cheap and fast to carry out compared to the analyses of phytoplankton biomass and species composition; the fact which has an effect on number of samples to be taken and thereby on the reliability of assessments. However, analyses on phytoplankton biomass and species composition provide more metrics for ecological classification, the metrics which reveal various aspects of eutrophication contrary to what Chl alone does.
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Boreal peatlands represent a considerable portion of the global carbon (C) pool. Water-level drawdown (WLD) causes peatland drying and induces a vegetation change, which affects the decomposition of soil organic matter and the release of greenhouse gases (CO2 and CH4). The objective of this thesis was to study the microbial communities related to the C cycle and their response to WLD in two boreal peatlands. Both sampling depth and site type had a strong impact on all microbial communities. In general, bacteria dominated the deeper layers of the nutrient-rich fen and the wettest surfaces of the nutrient-poor bog sites, whereas fungi seemed more abundant in the drier surfaces of the bog. WLD clearly affected the microbial communities but the effect was dependent on site type. The fungal and methane-oxidizing bacteria (MOB) community composition changed at all sites but the actinobacterial community response was apparent only in the fen after WLD. Microbial communities became more similar among sites after long-term WLD. Litter quality had a large impact on community composition, whereas the effects of site type and WLD were relatively minor. The decomposition rate of fresh organic matter was influenced slightly by actinobacteria, but not at all by fungi. Field respiration measurements in the northern fen indicated that WLD accelerates the decomposition of soil organic matter. In addition, a correlation between activity and certain fungal sequences indicated that community composition affects the decomposition of older organic matter in deeper peat layers. WLD had a negative impact on CH4 oxidation, especially in the oligotrophic fen. Fungal sequences were matched to taxa capable of utilizing a broad range of substrates. Most of the actinobacterial sequences could not be matched to characterized taxa in reference databases. This thesis represents the first investigation of microbial communities and their response to WLD among a variety of boreal peatland habitats. The results indicate that microbial community responses to WLD are complex but dependent on peatland type, litter quality, depth, and variable among microbes.
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The adequacy of anesthesia has been studied since the introduction of balanced general anesthesia. Commercial monitors based on electroencephalographic (EEG) signal analysis have been available for monitoring the hypnotic component of anesthesia from the beginning of the 1990s. Monitors measuring the depth of anesthesia assess the cortical function of the brain, and have gained acceptance during surgical anesthesia with most of the anesthetic agents used. However, due to frequent artifacts, they are considered unsuitable for monitoring consciousness in intensive care patients. The assessment of analgesia is one of the cornerstones of general anesthesia. Prolonged surgical stress may lead to increased morbidity and delayed postoperative recovery. However, no validated monitoring method is currently available for evaluating analgesia during general anesthesia. Awareness during anesthesia is caused by an inadequate level of hypnosis. This rare but severe complication of general anesthesia may lead to marked emotional stress and possibly posttraumatic stress disorder. In the present series of studies, the incidence of awareness and recall during outpatient anesthesia was evaluated and compared with that of in inpatient anesthesia. A total of 1500 outpatients and 2343 inpatients underwent a structured interview. Clear intraoperative recollections were rare the incidence being 0.07% in outpatients and 0.13% in inpatients. No significant differences emerged between outpatients and inpatients. However, significantly smaller doses of sevoflurane were administered to outpatients with awareness than those without recollections (p<0.05). EEG artifacts in 16 brain-dead organ donors were evaluated during organ harvest surgery in a prospective, open, nonselective study. The source of the frontotemporal biosignals in brain-dead subjects was studied, and the resistance of bispectral index (BIS) and Entropy to the signal artifacts was compared. The hypothesis was that in brain-dead subjects, most of the biosignals recorded from the forehead would consist of artifacts. The original EEG was recorded and State Entropy (SE), Response Entropy (RE), and BIS were calculated and monitored during solid organ harvest. SE differed from zero (inactive EEG) in 28%, RE in 29%, and BIS in 68% of the total recording time (p<0.0001 for all). The median values during the operation were SE 0.0, RE 0.0, and BIS 3.0. In four of the 16 organ donors, EEG was not inactive, and unphysiologically distributed, nonreactive rhythmic theta activity was present in the original EEG signal. After the results from subjects with persistent residual EEG activity were excluded, SE, RE, and BIS differed from zero in 17%, 18%, and 62% of the recorded time, respectively (p<0.0001 for all). Due to various artifacts, the highest readings in all indices were recorded without neuromuscular blockade. The main sources of artifacts were electrocauterization, electromyography (EMG), 50-Hz artifact, handling of the donor, ballistocardiography, and electrocardiography. In a prospective, randomized study of 26 patients, the ability of Surgical Stress Index (SSI) to differentiate patients with two clinically different analgesic levels during shoulder surgery was evaluated. SSI values were lower in patients with an interscalene brachial plexus block than in patients without an additional plexus block. In all patients, anesthesia was maintained with desflurane, the concentration of which was targeted to maintain SE at 50. Increased blood pressure or heart rate (HR), movement, and coughing were considered signs of intraoperative nociception and treated with alfentanil. Photoplethysmographic waveforms were collected from the contralateral arm to the operated side, and SSI was calculated offline. Two minutes after skin incision, SSI was not increased in the brachial plexus block group and was lower (38 ± 13) than in the control group (58 ± 13, p<0.005). Among the controls, one minute prior to alfentanil administration, SSI value was higher than during periods of adequate antinociception, 59 ± 11 vs. 39 ± 12 (p<0.01). The total cumulative need for alfentanil was higher in controls (2.7 ± 1.2 mg) than in the brachial plexus block group (1.6 ± 0.5 mg, p=0.008). Tetanic stimulation to the ulnar region of the hand increased SSI significantly only among patients with a brachial plexus block not covering the site of stimulation. Prognostic value of EEG-derived indices was evaluated and compared with Transcranial Doppler Ultrasonography (TCD), serum neuron-specific enolase (NSE) and S-100B after cardiac arrest. Thirty patients resuscitated from out-of-hospital arrest and treated with induced mild hypothermia for 24 h were included. Original EEG signal was recorded, and burst suppression ratio (BSR), RE, SE, and wavelet subband entropy (WSE) were calculated. Neurological outcome during the six-month period after arrest was assessed with the Glasgow-Pittsburgh Cerebral Performance Categories (CPC). Twenty patients had a CPC of 1-2, one patient had a CPC of 3, and nine patients died (CPC 5). BSR, RE, and SE differed between good (CPC 1-2) and poor (CPC 3-5) outcome groups (p=0.011, p=0.011, p=0.008, respectively) during the first 24 h after arrest. WSE was borderline higher in the good outcome group between 24 and 48 h after arrest (p=0.050). All patients with status epilepticus died, and their WSE values were lower (p=0.022). S-100B was lower in the good outcome group upon arrival at the intensive care unit (p=0.010). After hypothermia treatment, NSE and S-100B values were lower (p=0.002 for both) in the good outcome group. The pulsatile index was also lower in the good outcome group (p=0.004). In conclusion, the incidence of awareness in outpatient anesthesia did not differ from that in inpatient anesthesia. Outpatients are not at increased risk for intraoperative awareness relative to inpatients undergoing general anesthesia. SE, RE, and BIS showed non-zero values that normally indicate cortical neuronal function, but were in these subjects mostly due to artifacts after clinical brain death diagnosis. Entropy was more resistant to artifacts than BIS. During general anesthesia and surgery, SSI values were lower in patients with interscalene brachial plexus block covering the sites of nociceptive stimuli. In detecting nociceptive stimuli, SSI performed better than HR, blood pressure, or RE. BSR, RE, and SE differed between the good and poor neurological outcome groups during the first 24 h after cardiac arrest, and they may be an aid in differentiating patients with good neurological outcomes from those with poor outcomes after out-of-hospital cardiac arrest.