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  • Yli-Mäyry, Soile (Helsingin yliopisto, 2011)
    AESTHETIC EXPERIENCE AS A BRIDGE ACROSS CULTURES Soile Yli-Mäyry s art as experienced by Chinese, Japanese and Finnish audiences This study focuses on surveying and analysing experiences of Soile Yli-Mäyry s art in eleven different countries. Questionnaires were translated into nine different languages. In addition, interviews were conducted on the experiences of Chinese, Japanese and Finnish art audiences concerning a painting called Sun Wind . The study was mainly inspired by John Dewey s ideas of art as an interactive communication where the artist, the piece and those who experience it make up an interactive process. In this process experience is a meeting point with both individual and communal characteristics. The data was collected in conjunction with exhibitions in 1997−2005. The survey was carried out in eleven countries (Finland, United States, Brazil, China, Taiwan, Japan, India, Israel, Argentina, Germany and Switzerland). The survey data was made up of 2,563 returned questionnaires. The interviews in China, Japan and Finland were about the same painting Sun Wind , which was transported from Finland to Japan (Tokyo) and China. A total of 89 people were interviewed in Shanghai Art Museum, 30 people in Port-Ginza Gallery, Tokyo and 45 people in Soile Yli-Mäyry s Gallery in Finland. Three hypotheses that were turned into research questions directed the study: 1. Are there differences/ similarities between culturally different communities in the meanings attributed to experiences, e.g. according to emotional dimensions, or do experiences focus more on reflecting on one s own life or meanings attributed to the world around us? What kinds of experiential dimensions are there in different countries? Do similar, analogous experiences that transcend cultural barriers emerge in culturally different countries such as China, Japan and Finland? 2. Does the data display different types of experiencing subjects which are typical to a subject s own country or are they experiences that can be compared to those generated by an ideal landscape , where the art touches the subconscious and collective selfhood, being thus transnational and timeless? Closer analysis focuses on audience experiences in China, Japan and Finland (interviews, textual survey data). 3. Are the experiences and interpretations of experts similar/different to those of larger audiences? The survey data has been analysed with the help of cross-tabulation. After content analysis of the interviews and textual survey data, different ways of experiencing subjects were sketched by country (China, Japan, Finland). The types were both similar and dissimilar. The most important types were social/ecological (China), therapeutic/reserved (Japan) and narrative/projecting (Finland). There were differences in how experiences were emphasised: the Chinese public approached their experiences from the viewpoint of pragmatism and utility, where they could obtain new ideas for their own work or experiencing the exhibition gave courage to approach their own lives from a new perspective. In turn, the Japanese public experienced the art from a therapeutic angle and from a very reserved perspective, which Dylan Evans (2001, 13−17) has described as typical to Japanese culture. The experiences of the Finnish audience were strongly therapeutic and narrative. The people projected their emotions onto the piece and in a concrete manner forged them into a story. The partly similar results of this study in China, Japan and Finland demonstrate that the art displayed in the exhibitions contain images of the beginning or elements connected to the beginning of life, which touch the subconscious in the way an ideal landscape would. Experiencing the meaningfulness of one s own life through art is a common thread and a bridge across cultures that unites the experiences of the audiences of this study, be they Taoists, Confucians, Buddhists or Maoists in China, Shinto followers, Zen Buddhists in Japan or Evangelist-Lutherans in Finland. Keywords: experience, reception, bridge across cultures, types of experiencing subjects, experiential process, ideal landscape, elementality
  • Sartonen, Matti (2015)
    Tämän tutkielman tehtävänä on selvittää, minkälainen on Lutherin käsitys teologian ja filosofian välisestä suhteesta. Tutkielman lähteenä ovat viisi disputaatiota vuosilta 1517–1540, joihin Luther on laatinut teesit: disputaatio skolastista teologiaa vastaan (1517), Heidelbergin disputaatio (1518), disputaatio ihmisestä (1536), disputaatio lauseesta ”Sana tuli lihaksi” (Joh. 1.14) (1539) ja disputaatio Kristuksen jumalallisuudesta ja inhimillisyydestä (1540). Tutkielman metodina on systemaattinen analyysi. Aluksi on käännetty kaikkien viiden disputaation kaikki teesit. Tämä on tehty siksi, että näin on mahdollista muodostaa kokonaiskuva jokaisesta disputaatiosta ja asettaa tutkielman aihetta koskevat teesit niille alun perin tarkoitettuun kontekstiin. Teesien suomentamisen jälkeen on jokaisen disputaation kohdalla syvennytty siihen, minkälaisia tutkielman aiheeseen liittyviä teemoja kussakin niistä esiintyy. Varhaisia disputaatioita (3. luku) käsittelevissä alaluvussa käsitellään nuoren Lutherin käsitystä tahdosta, logiikasta sekä paradoksien teologiasta. Vastaavasti myöhäisiä disputaatioita (4. luku) käsittelevissä alaluvuissa perehdytään vanhemman Lutherin käsitykseen järjestä ja epistemologiasta sekä hänen käsitykseensä teologisesta kielestä. Tutkielman aihepiirin liittyvät ja ymmärtämisen kannalta tarpeelliset taustatiedot on koottu johdantoa seuraavaan taustalukuun (2. luku), jossa käsitellään teologian ja filosofian välistä suhdetta keskiajalla. Viidennessä luvussa vedetään yhteen tutkielman johtopäätelmät. Luther tarkastelee asioita pääosin suhteessa Jumalaan. Tarkasteltaessa nuoren Lutherin käsitystä tahdosta kävi ilmi, ettei Luther kritisoi järkeä per se vaan pyrkii osoittamaan, että syntiinlankeemuksen seurauksena nimenomaan tahto on turmeltunut. Tämän seurauksena pahaan sidottu tahto muodostaa ihmiselle vääristyneen lähtökohdan, josta käsin hän tarkastelee maailmaa. Vastaavasti Luther ei varhaisissa disputaatioissa kritisoi logiikkaa sinänsä. Hän näkee niin teologian kuin filosofian muodostavan omat disipliininsä. Termien merkitys on vastaavasti disipliinisidonnaista eikä termejä voi sellaisenaan siirtää disipliinistä toiseen. Teologiset termit (esim. trinitaariset ja kristologiset termit) viittaavat kohteeseensa tavallisuudesta poikkeavalla tavalla ja näin ollen syllogismit eivät sovellu teologisen materian käsittelyyn. Nuoren Lutherin ”paradoksien teologian” tutkiminen paljasti, että ihminen ei Lutherin mukaan luonnostaan hahmota omaa tilannettaan Jumalan edessä. Ihminen olettaa virheellisesti analogian vallitsevan luodun maailman ja Jumalan välillä. Näistä lähtökohdista ihminen myös muodostaa virheellisen kuvan Jumalasta ja harjoittaa filosofiaa vääristä lähtökohdista. Kristus puolestaan muodostaa ”tulkinnan avaimen”, jonka avulla ihmisen perspektiivi korjataan. Lutherin myöhäisten disputaatioiden pohjalta kävi ilmi, että Luther arvostaa järjen kaikkea muuta korkeammalle tässä maailmassa. Suhteessa jumalalliseen viisauteen inhimillinen viisaus ei kuitenkaan ole juuri mitään. Episteemisesti Luther näkee niin teologisen kuin inhimillisen tiedon olevan luonteeltaan a posteriorista. Teologisen tiedon lähteenä toimii Raamattu. Perustuen eri disipliineihin sama väitelause ei ole Lutherin mukaan totta teologiassa ja filosofiassa. Teologian kohteet edellyttävät uutta kieltä, sillä ne ovat itsessään sanoinkuvaamattomia ja käsittämättömiä. Kokonaisuutena tutkielmasta käy ilmi, ettei Lutherin kritiikki kohdistu järkeen tai logiikkaan per se vaan Luther hyödyntää niitä itse myös teologian alueella. Lutherin näkökulmasta filosofiaan kytköksissä olevat ongelmat liittyvät syntiinlankeemuksen seurauksiin: ihmisellä ei ole luonnostaan tietoa Jumalasta eikä hän hahmota omaa tilannettaan. Kristuksen kautta ihmisen perspektiivi voidaan kuitenkin korjata.
  • Mäkelä, Hanna (Helsingin yliopisto, 2015)
    Roughly three-quarters of Finland s area is covered by forests. Any climatological changes influencing the danger of forest fire are important to evaluate and consider. The objective of this thesis is to study the long-term past and future changes in climatically-driven forest fire danger in Finland based on the summertime mean temperature and precipitation sum. The work is composed of two parts. In the first part, long-term gridded datasets of observed monthly mean temperatures and precipitation sums for Finland are developed. In the second part, these gridded datasets are used together with calculated values of the Finnish Forest Fire Index and probabilistic climate model simulations (from the ENSEMBLES project) to estimate the number of forest fire danger days during the summer season (June-August). The long-term variation of Finland s climatological forest fire danger is studied roughly for 100 years backwards and into the future. One of the main achievements of this thesis is that it explores the possibility of quantifying past and future fire-weather using a relatively limited database with regard to both weather variables and their spatial coverage. This enables a wider exploitation of scattered data series from earlier times and can also provide opportunities for projections using data with a low resolution. The climatological forest fire danger in Finland varies considerably from year to year. There have not been any significant increasing or decreasing trends in the number of fire danger days during the 20th century (1908-2011). On average, the highest probability of forest fire danger occurs in June and July, when a fire hazard exists on roughly 35-40% of all days. The intra-seasonal variation of fire danger has been large enough to enable the occurrence of conflagrations even though the fire danger for the season as a whole has been at an average level. Despite the projected increase in average summertime precipitation, the Finnish climate will provide more favourable conditions for the occurrence of forest fires in the future than today. This is due to increases in the mean temperature. The probability of an increase in the number of fire danger days is 56-75% in the near future (2010-2029) and 71-91% by the end of the current century (2080-2099), depending on the region. This would indicate an increase of 1-2 and 7-10 days, respectively. It is thus clearly important to further develop existing tools for the forecasting of fire danger, and to maintain the capabilities of the fire prevention, surveillance and suppression services. Future projections of all relevant meteorological variables (temperature, precipitation, humidity, evaporation and wind speed) at higher temporal and spatial resolutions, in addition to information on the type of the summertime precipitation and the length of the dry periods, would notably improve the assessment of the future climatological forest fire danger.
  • Itkonen, Pekka (2012)
    The indigenous forests of the Taita Hills, SE Kenya, boast a vast biodiversity and provide several vital ecosystem services to local communities. Population growth and land use change pressures have resulted in a significant decrease in indigenous forest cover in the Taita Hills in recent decades. Quantifying the aboveground biomass (agb) and carbon sequestration capacity of the Taita forests provides a strong argument for striving for their more efficient protection in the context of UN-REDD programme. Although the role of tropical forests as global carbon sinks has been widely recognized, their agb and leaf area index (LAI) remain uncertain. Optical remote sensing (RS) provides a cost-effective means of LAI and agb estimation in remote areas, but empirical modeling using remote sensor data has limited certainty in densely vegetated tropical forests. The agb and LAI of the Taita Hills were estimated using empirical regression modeling by relating in situ data (n = 181 for agb, n = 172 for LAI) and spectral vegetation indices (SVIs) derived from SPOT HRVIR optical remote sensing data. Field plots (20 m x 20 m = 0.04 ha) were located in indigenous (n = 80) and exotic (n = 83) forests, woodlands (n = 9) and agroforestry areas (n = 9). In situ LAI was derived from hemispherical photography (HP) using Lang's approach and the foliage clumping correction method by Chen & Cihlar. In situ agb was estimated using allometric equations which relate agb with tree parameters such as tree diameter at breast height. Empirical relations between the response variables (agb, LAI) and SVIs were utilized in predictive regression modeling. The predictor variables were selected using forward stepwise regression based on Akaike Information Criterion (AIC) values. The regression models resulted having only one predictor each due to the redundancy of the SVIs. Also topography-based predictor variables were tested, but they were poorly or not at all related with LAI and agb. The models performed moderately (D2 = 0.62 for LAI model, D2 = 0.41 for agb model). The total agb and carbon sequestration of the study area were estimated as 4.264 Tg and 2.132 Tg C, respectively. Mean agb densities of the indigenous forests and the whole study area were estimated as 463 ± 190 Mg ha-1 and 126 ± 115 Mg ha-1, respectively. Mean in situ LAI of the indigenous forests and all plots were estimated as 3.66 ± 0.44 and 3.12 ± 0.84, respectively. Indigenous plots had the highest mean in situ agb density and LAI values compared to exotic forests, woodlands and agroforestry areas (ANOVA p < 0.001). The RMSE values of the models were 0.59 (18.6 %) for LAI and 376.85 Mg ha-1 (82.9 %) for agb. The agb model was negatively biased (bias: -107.1 Mg ha-1, 23.6%), but there was no statistically significant bias in the LAI model. The resulting agb estimates are rather high due to high in situ agb values, partly resulting from the emphasized contribution of very large trees to biomass on small plots. LAI values are quite low for dense tropical forests due to indirect estimation method using HP, but still comparable with other similar studies. As expected, the modeling performance was impaired by SVI saturation effect in relation to LAI and agb. The agb model was biased most likely due to the use of transformed variables in linear regression. The predictive models are not transferable to other regions as such, for the relative prediction performance of SVIs is case-specific and the model parameters have to be estimated using in situ data for each site. In order to improve the model credibility, a more extensive dataset based on a random or a systematic sample should be used, having larger plot size and containing more observations with low LAI and agb values.
  • Viskari, Toni (Helsingin yliopisto, 2012)
    Atmospheric aerosol particles have several important effects on the environment and human society. The exact impact of aerosol particles is largely determined by their particle size distributions. However, no single instrument is able to measure the whole range of the particle size distribution. Estimating a particle size distribution from multiple simultaneous measurements remains a challenge in aerosol physical research. Current methods to combine different measurements require assumptions concerning the overlapping measurement ranges and have difficulties in accounting for measurement uncertainties. In this thesis, Extended Kalman Filter (EKF) is presented as a promising method to estimate particle number size distributions from multiple simultaneous measurements. The particle number size distribution estimated by EKF includes information from prior particle number size distributions as propagated by a dynamical model and is based on the reliabilities of the applied information sources. Known physical processes and dynamically evolving error covariances constrain the estimate both over time and particle size. The method was tested with measurements from Differential Mobility Particle Sizer (DMPS), Aerodynamic Particle Sizer (APS) and nephelometer. The particle number concentration was chosen as the state of interest. The initial EKF implementation presented here includes simplifications, yet the results are positive and the estimate successfully incorporated information from the chosen instruments. For particle sizes smaller than 4 micrometers, the estimate fits the available measurements and smooths the particle number size distribution over both time and particle diameter. The estimate has difficulties with particles larger than 4 micrometers due to issues with both measurements and the dynamical model in that particle size range. The EKF implementation appears to reduce the impact of measurement noise on the estimate, but has a delayed reaction to sudden large changes in size distribution.
  • Helander, Maria (2014)
    The aim of this thesis is to study the effects of household wealth on consumption. The focus of the study is on the effects of physical wealth, namely housing and forest wealth, on consumption in Finland. The empirical estimation is conducted using cross-sectional household level data obtained from the 1998 Household Wealth Survey compiled by Statistics Finland. The estimation is performed using OLS regression and taking into account survey design considerations. The results from the study provide evidence confirming the existence of a wealth effect on consumption regarding housing wealth, forest wealth as well as financial wealth. The study finds the housing wealth effect on consumption to be positive and much larger than the financial wealth effect for those households that are homeowners. However, the magnitude and the sign of the wealth effect seems to somewhat differ by the amount of accumulated net housing wealth. Evidence of the existence of a life-cycle pattern in consumption is also confirmed for the subsample of homeowners by comparing differences in wealth effects between household age groups. It should however be emphasised, that actual life-cycle behaviour can only be traced with the use of panel data. The study finds evidence that the effect of forest wealth on consumption may be negative for the subsample of forest owners. Further study then reveals that the negative estimate for the effect of net forest wealth on consumption observed for the whole subsample seems to arise from the much stronger and significant negative estimate obtained for the subgroup of forest owning farmer households. This finding could in part be explained by the skewed age distribution of forest owning households, the fact that forest owning farmer households are likely to be engaging more in home production, which lowers observed consumption outside of the home, and that farmer owned forestland estates, and the logging income they generate, are often used for funding farm associated investments. In order to study the concavity of the consumption function in Finland, wealth and income effects are estimated separately for the net wealth quintiles of households using the whole sample of observations. The results indicate that the effect of a change in financial wealth or income on consumption is indeed larger for households with small total net wealth. This finding suggests that in the case of a wealth or income shock that disproportionately affects households with less net wealth, the economy level effects on aggregate consumption may be larger than those estimated by traditional models.
  • Juntheikki, Joni (2014)
    Purpose of this thesis is to estimate the carbon sequestration potential in eucalyptus plantations in Uruguay. This study also aims to show how beneficial these plantations are for carbon sinks. The aim of this research is calculate total carbon balance in eucalyptus plantations and compare the results to degraded lands. This study is first-of-its-kind study in Uruguay, but not unique globally. The objective was to use a modeling approach to formulate the results. The methodology of this study is based to the dynamic growth model (CO2fix V3.1). Model is developed to calculate and estimate forest carbon fluxes and stocks. In this study the model was utilized for estimating how much carbon is sequestered in eucalyptus plantations and soils. In this thesis the model was used to simulate eucalyptus forest plantations that stem from numerous studies and different data. Ad hoc Excel model was generated to form calculated results from the simulated data. A separate sensitivity analysis is also formulated to reveal a possible different outcome. The framework is based on a stand-level inventory data of forestry plantations provided by the Ministry of Uruguay (MGAP) and companies. Also multiple scientific reports and previous studies were used as guidelines for simulations and results. The forest stand, yield, soil and weather data used for this study are from three different departments. There are over 700 000 hectares of different species of eucalyptus plantations in Uruguay. The theoretical framework was tested computationally with eleven simulations. CO2fix was parameterized for fast-growing eucalyptus species used in different parts of Uruguay. The model gave outputs per hectare and then this result was scaled up to the national level. This study will also estimate how much grassland (Pampa) and former pasture land could sequester carbon. Situation prior to plantation is a baseline scenario and it is compared to the expected carbon sequestration of plantations. The model is also used to calculate the effect of changing rotation length on carbon stocks of forest ecosystem (forest vegetation and soil) and wood products. The results of this study show that currently the 707,674 hectares of eucalyptus plantations in Uruguay have the potential to sequester 65 million tonnes of carbon and reduce 238 million tonnes of CO2. The calculated carbon storage is 38 and simulated 25 million tonnes of C, products are deducted from the equation. During 22 years (1990–2012) the annual carbon sequestration benefit (afforestation-baseline) without products is 1 757 847 Mg C. The results suggest that it is reasonable to establish eucalyptus plantations on degraded, grassland (Pampa) and abandoned pasture land. The implications of the results are that eucalyptus plantations in Uruguay actually enhance carbon sequestration, are carbon sinks and store more carbon than grassland and abandoned pasture land. Plantations have a vast sequestration potential and are important in mitigating of CO2 emission and effects of the climate change. The findings endorse the significance of plantations to increase carbon sinks and this role will broaden in the future. The most relevant findings of this study are that afforestation increases the soil carbon in 10-year rotation plantations by 34% (101.1>75.6) and in 12-year rotation 38% (104.4>75.6 Mg Cha-1) in a 60-year simulation. The net (afforestation-baseline) average carbon stock benefit in the soil is 25.5 Mg C ha−1 in a 60-year simulation. The (CO2Fix) model indicate that the total average carbon sequestration for eucalyptus plantations is 92.3 Mg Cha−1. The average total carbon storage ranges from 25.8–138.5 Mg Cha−1 during a 60-year simulation. The simulations show that the net annual carbon storage in the living biomass is 29.1, 25.5 (soil) and 37.6 Mg C (products) on the average scenario. There is some fluctuation in the sequestration results in other 10 simulations. Previous studies have showed that the average carbon stock for eucalyptus plantations varies from 30–60 Mg C ha-1, when soil and products are deducted. The capacity of forest ecosystems to sequester carbon in the long run could be even more strengthened if a rotation length increases. Extending rotation from 10 to 12 years increased the average soil carbon stock from 25.5 to 28.8 Mg C (by 13%) in 60 year simulation. The results also indicate that mean annual precipitation (MAP) alters the carbon sinks of the forest ecosystem. There are some limitations in this study and they are clearly explained and analyzed. Hence, most of the results are estimations. Ministry and companies need to prolong planting of trees and even intensify annual programs in order to achieve carbon sequestration targets. Further research is needed to get an estimate of the total forest ecosystem carbon storages and fluxes.
  • Ojanen, Paavo (2014)
    In this study, 1) a model to estimate soil carbon dioxide (CO2) balance for forestry-drained peatlands was tested on site and countrywide levels in Finland. 2) A dataset of annual soil atmosphere fluxes of CO2, methane (CH4) and nitrous oxide (N2O) from 68 sites was collected, and models fitted for their upscaling to a countrywide level. 3) The current greenhouse gas impact of the 68 study sites, including soil CO2, CH4 and N2O balances and the CO2 sink function of tree biomass increment, was estimated. The soil CO2 balance estimation, as the difference between litter input to soil and CO2 efflux from soil, was straightforward to apply, but considerable uncertainty was caused by the inadequate level of knowledge on belowground plant soil carbon fluxes. Soil atmosphere gas fluxes could be upscaled to a countrywide level utilizing readily available forest inventory results and weather statistics. Soils in nutrient-rich study sites were sources of greenhouse gases while those in nutrient-poor study sites were sinks, on average. The current greenhouse gas impact, when no forest fellings occurred, was nevertheless climate cooling for both the nutrient-rich and poor sites due to the considerable CO2 sink formed by increasing tree biomass.
  • Majasalmi, Titta (Helsingin yliopisto, 2015)
    The aim of this dissertation is to assess the accuracy of different ground reference methods used to validate satellite based leaf area index (LAI) and the fraction of absorbed photosynthetically active radiation (fPAR) products. LAI and fPAR are strongly linked, although they principally and practically measure different properties: LAI quantifies the areal interphase between soil and atmosphere, whereas fPAR quantifies the energy available for photosynthesis. Until now, the development of remote sensing based methods to estimate LAI and fPAR in a boreal forest has been hindered by the scarcity of ground data, which is required to validate and develop existing algorithms. The aim of the first part of this dissertation was to assess the impacts of different methodological approaches to estimate LAI in boreal forests, and to validate satellite based LAI products. Results showed that the accuracy of ground based LAI estimates is sensitive to both the retrieval methods and sampling scheme used to collect the optical LAI data. The satellite based measurements of LAI demonstrated a large temporal variability in LAI. The second part of the dissertation focused on measuring and modeling fPAR in a boreal forest. A new scheme for measuring and modeling ground reference fPAR based on photon recollision probability was presented in this dissertation. Ground reference fPAR is usually estimated only for the forest canopy layer. This study is among the first ones to validate the new global satellite based fPAR product called GEOV1 using data of both the forest canopy and understory layers from boreal forests. Results showed that satellite based fPAR products may correspond better with the total fPAR, instead of only the forest canopy fPAR as has often been presumed.
  • Tuominen, Sakari (Helsingin yliopisto, 2007)
    This thesis examines the feasibility of a forest inventory method based on two-phase sampling in estimating forest attributes at the stand or substand levels for forest management purposes. The method is based on multi-source forest inventory combining auxiliary data consisting of remote sensing imagery or other geographic information and field measurements. Auxiliary data are utilized as first-phase data for covering all inventory units. Various methods were examined for improving the accuracy of the forest estimates. Pre-processing of auxiliary data in the form of correcting the spectral properties of aerial imagery was examined (I), as was the selection of aerial image features for estimating forest attributes (II). Various spatial units were compared for extracting image features in a remote sensing aided forest inventory utilizing very high resolution imagery (III). A number of data sources were combined and different weighting procedures were tested in estimating forest attributes (IV, V). Correction of the spectral properties of aerial images proved to be a straightforward and advantageous method for improving the correlation between the image features and the measured forest attributes. Testing different image features that can be extracted from aerial photographs (and other very high resolution images) showed that the images contain a wealth of relevant information that can be extracted only by utilizing the spatial organization of the image pixel values. Furthermore, careful selection of image features for the inventory task generally gives better results than inputting all extractable features to the estimation procedure. When the spatial units for extracting very high resolution image features were examined, an approach based on image segmentation generally showed advantages compared with a traditional sample plot-based approach. Combining several data sources resulted in more accurate estimates than any of the individual data sources alone. The best combined estimate can be derived by weighting the estimates produced by the individual data sources by the inverse values of their mean square errors. Despite the fact that the plot-level estimation accuracy in two-phase sampling inventory can be improved in many ways, the accuracy of forest estimates based mainly on single-view satellite and aerial imagery is a relatively poor basis for making stand-level management decisions.
  • Hautaniemi, Mikaela (2012)
    Lääkevalmistuksessa amorfista muotoa käytetään, esimerkiksi parantamaan liukoisuusnopeutta, stabiloimaan proteiinien rakennetta säilytyksen aikana ja parantamaan apuaineiden käsiteltävyyttä. Aine voi muuttua osittain tai kokonaan amorfiseen muotoon monen tavallisen lääkevalmistusprosessin, kuten kalvopäällystyksen, rakeistuksen, kuivauksen, jauhatuksen ja puristuksen seurauksena. Amorfisten alueiden läsnä ollessa aineen fysikaaliset ominaisuudet muuttuvat merkittävästi, mikä vaikuttaa lääkevalmisteen fysikaaliseen ja kemialliseen säilyvyyteen. Amorfisen aineen molekyylimobiliteetti on tärkeä lasitilan pysyvyyttä kuvaava parametri. Tämän vuoksi on tärkeää arvioida se lääkekoostumussuunnittelun alkuvaiheessa. Tutkimuksen tavoitteena oli määrittää differentiaalista pyyhkäisykalorimetriaa (DSC) apuna käyttäen neljän amorfisen disakkaridin molekyylimobiliteettia alhaisissa (verrattuna Tg:seen) lämpötiloissa. Relaksaatio tapahtuu tutkituissa lämpötiloissa hyvin hitaasti. Niin hitaasti, että alkurelaksaationopeutta voidaan käyttää hyväksi relaksaatioprosessin kokonaisuuden arvioinnissa. Tutkimuksessa käytetyillä disakkarideilla on todettu olevan samanlainen relaksaatiotaipumus, kun tätä arvioidaan lasisiirtymälämpötilan (Tg) -arvon perusteella. Korkeamman Tg:n omaavilla yhdisteillä lasitila on tavallisesti pysyvämpi. Sakkaroosin Tg on alhaisin tutkimuksessa käytetyistä disakkarideista. Amorfisella mellibioosilla, trehaloosilla ja selibioosilla on kahden vuoden relaksaatioaika säilytettäessä lämpötilassa Tg-55oC. Amorfisen sakkaroosin kohdalla tarvitaan alhaisempi säilytyslämpötila (Tg-70oC) samansuuruisen relaksaationopeuden saavuttamiseen. Fragiliteettia voidaan käyttää amorfisten aineiden luokitteluun ja vertailuun. Kaikki tutkimuksessa käytetyt disakkaridit voidaan luokitella hauraiksi yhdisteiksi. Fragiliteetin arvot laskettiin kolmen eri menetelmän avulla. Tuloksina saatiin kolme jossain määrin erilaista fragiliteettijärjestystä. Tulosten epäyhtenevyys johtuu ainakin osittain DSC -laitteiston ominaisuuksista. Tutkimuksessa käytettyä menetelmää on vaikea soveltaa ilman muiden menetelmien tukitietoja. Tg:n riippuvuudella lämmitysnopeudesta on tärkeä merkitys, tästä syystä pienikin poikkeama ko. arvoissa saa aikaan merkittävät muutokset lopputulokseen. Tästä huolimatta tutkimuksen lopputuloksena saatujen relaksaatioajan arvojen voidaan todeta olevan yhdenmukaisia aikaisimpien tutkimuksien kanssa.
  • Latva-Käyrä, Petri (2012)
    The intensity and frequency of insect outbreaks have increased in Finland in the last decades and they are expected to increase even further in the future due to global climate change. In 1998-2001 Finland suffered the most severe insect outbreak ever recorded, over 500,000 hectares. The outbreak was caused by the common pine sawfly (Diprion pini L.). The outbreak has continued in the study area, Palokangas, ever since. To find a good method to monitor this type of outbreaks, the purpose of this study was to examine the efficacy of multitemporal ERS-2 and ENVISAT SAR imagery for estimating Scots pine defoliation. The study area, Palokangas, is located in Ilomantsi district, Eastern-Finland and consists mainly even-aged Scots pine forests on relatively dry soils. Most of the forests in the area are young or middle-aged managed forests. The study material was comprised of multi-temporal ERS-2 and ENVISAT synthetic aperture radar (SAR) data. The images had been taken between the years 2001 and 2008. The field data consisted 16 sample plots which had been measured seven times between the years 2002 and 2009. In addition, eight sample plots were added afterwards to places which were known to have had cuttings during the study period. Three methods were tested to estimate Scots pine defoliation: unsupervised k-means clustering, supervised linear discriminant analysis (LDA) and logistic regression. In addition, it was assessed if harvested areas could be differentiated from the defoliated forest using the same methods. Two different speckle filters were used to determine the effect of filtering on the SAR imagery and subsequent results. The logistic regression performed best, producing a classification accuracy of 81.6% (kappa 0.62) with two classes (no defoliation, >20% defoliation). LDA accuracy was with two classes at best 77.7% (kappa 0.54) and k-means 72.8 (0.46). In general, the largest speckle filter, 5 x 5 image window, performed best. When additional classes were added the accuracy was usually degraded on a step-by-step basis. The results were good, but because of the restrictions in the study they should be confirmed with independent data, before full conclusions can be made that results are reliable. The restrictions include the small size field data and, thus, the problems with accuracy assessment (no separate testing data) as well as the lack of meteorological data from the imaging dates.
  • Ruokonen, Inkeri (Helsingin yliopisto, 2005)
  • Andrespok, Evelin (2014)
    Estonia became a donor of development assistance in 1998 as it was in the process of joining the EU. Since the early days of being a donor, the Estonian approach has been to share its transition experience with other countries that share a similar past with the country. This thesis explores why and how Estonia aspires to offer added value with its development cooperation through sharing its transition experience and to what is the impact of its assistance. More precisely, this thesis takes a qualitative project level look at the added value of Estonian development cooperation by examining how Estonia shared its experience of computerising schools with the Republic of Georgia though the educational reform titled Deer Leap. Conceptualising sharing transition experience as a tool for democratisation, and thereby development, it argues that the unique added value that Estonia offers to developing countries is the “transition experience” itself, because there is personal expertise gathered from implementing the very same reforms in Estonia. Also, Estonia the partner countries see Estonia as role model in moving towards the EU. These conclusions are helpful for understanding whether at all and to what extent a small donor like Estonia can support positive developments and democratisation in partner countries.
  • Höckerstedt, Anna Illike (Helsingin yliopisto, 2004)
  • Ståhlberg, Kaarlo (Helsingin yliopisto, 2011)
    The purpose of this study was to deepen our knowledge of the combined use of estramustine and radiotherapy in the treatment of prostate cancer. Prostate cancer is a common disease, with a high variability between subjects in its malignant potential. In many cases, the disease is an incidental finding with little or no clinical significance. In other cases, however, prostate cancer may be an aggressive malignant disease, which, if the initial treatment fails, lacks an effective cure and may lead to severe symptoms, metastasis, and death despite all treatment. In many cases, the methods of treatment available at the moment provide cure or significant regression of symptoms, but often at the cost of considerable side effects. Estramustine, a cytostatic drug used for treating advanced cancer of the prostate, has been shown to inhibit prostate cancer progression and also to increase the sensitivity of cancer cells to radiotherapy. The goals of this study were, first, to find out whether it is possible to use either estramustine or an antibody against estramustine binding protein as carrier molecules for bringing therapeutic radioisotopes into prostate cancer cells, and, secondly, to gain more understanding of the mechanisms behind the known radiosensitising effect of estramustine. Estramustine and estramustine binding protein antibody were labelled with iodine-125 to study the biodistribution of these substances in mice. In the first experiment, both of the substances accumulated in the prostate, but radioiodinated estramustine also showed affinity to the liver and the lungs. Since the radiolabelled antibody was found out to accumulate more selectively to the prostate, we studied its biodistribution in nude mice with DU-145 human prostate cancer implants. In this experiment, the prostate and the tumour accumulated more radioactivity than other organs, but we concluded that the difference in the dose of radiation compared to other organs was not sufficient for the radioiodinated antibody to be advocated as a carrier molecule for treating prostate cancer. Mice with similar DU-145 prostate cancer implants were then treated with estramustine and external beam irradiation, with and without neoadjuvant estramustine treatment. The tumours responded to the treatment as expected, showing the radiation potentiating effect of estramustine. In the third experiment, this effect was found without an increase in the amount of apoptosis in the tumour cells, despite previous suggestions to the contrary. In the fourth experiment, we gave a similar treatment to the mice with DU-145 tumours. A reduction in proliferation was found in the groups treated with radiotherapy, and an increased amount of tumour hypoxia and tumour necrosis in the group treated with both neoadjuvant estramustine and radiation. This finding is contradictory to the suggestion that the radiation sensitising effect of estramustine could be attributed to its angiogenic activity.
  • Granvik, Anton (Helsingin yliopisto, 2004)
    Prepositioner är välkända för sin polysemi eller betydelsemångfald, och utgångspunkten för den här uppsatsen har varit ett intresse av att undersöka om det är möjligt att för en av de mest mångtydiga spanska prepositionerna, DE, finna en sammanhängande semantisk struktur, eller om det är nödvändigt att se de olika betydelserna som inbördes orelaterade. För att utreda den här frågan och ge den ett diakroniskt perspektiv undersöker jag i den här uppsatsen användningen av den spanska prepositionen DE i två romaner ur den spanska litteraturhistorien, Libro del caballero Zifar och El ingenioso hidalgo don Quijote de la Mancha, del I. Uppsatsen består av tre delar. I kapitel två ger jag en teoretisk översikt över spanskans prepositionssystem och prepositionerna beskrivs både ur syntaktisk och semantisk synvinkel. Dessutom presenteras den kognitiva grammatiken och dess synsätt på prepositioner. Huvuddelen av arbetet koncentrerar sig på att presentera prepositionen DE på två sätt och enligt två skilda metoder. I kapitel tre presenteras de olika kontextuella användningarna av DE enligt den traditionella, historisk-komparativa metoden. Med utgångspunkt i dessa kontextuella användningar ställer jag i kapitel fyra med stöd av den kognitiva grammatikens begreppssystem upp en semantisk nätverksmodell av de olika betydelser som jag fastställt för DE i den funktionella analysen. För den semantiska beskrivningen har jag använt mig av den kognitiva grammatiken, eftersom denna grammatikuppfattning i motsats till den traditionella grammatiken ser polysemin som regel och utgångspunkt i den semantiska strukturen. Analysdelen av uppsatsen inleds med den funktionella presentationen av användningarna av DE av två grundläggande skäl: För det första anser jag det ändamålsenligt att för den semantiska beskrivningen ha en solid bas av exempel där användningen av DE analyserats med hänsyn till kontexten. Kapitel tre är därför indelat i fyra huvuddelar, enligt vilken ordklass DEs huvudord tillhör, t.ex.: substantiv, adjektiv, verb. I exemplen i den fjärde gruppen fungerar prepositionsfrasen som inleds av DE som en mer fristående bestämning på frasnivå, där huvudordets ordklasstillhörighet inte är av avgörande betydelse. För det andra utgår jag från att en viss utveckling av DE har skett under de 300 år som tidsmässigt skiljer de båda romanerna åt, både vad gäller dess användning och dess semantik. För att komma underfund med och beskriva utsträckningen hos denna utveckling är det nödvändigt att den komparativa delen presenteras innan den semantiska beskrivningen kan inledas. Resultaten av den komparativa analysen är att ett antal smärre skillnader i användningen förekommer, men detta till trots har ingen betydande semantisk utveckling kunnat iakttas. Detta innebär att den semantiska beskrivningen av DE kan göras utifrån ett relativt enhetligt material. Jag har följaktligen också kunnat ställa upp en enhetlig semantisk nätverksmodell av tolv olika, relaterade betydelser hos DE. Utgående från mitt material är det sålunda möjligt att se DEs polysemi som ett sammanhängande nätverk, trots att vissa av betydelserna kan verka sinsemellan motstridiga och att 300 år skiljer åt de två böckerna. Nyckelord: prepositioner, DE: semantik och användning, polysemi, kognitiv grammatik, diakroni