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  • Öhberg, Annika (2017)
    Tutkimuksen tavoitteena on selvittää Festuca rubra subsp. oelandica -alalajin mahdollinenkäyttöarvo geenivarantona jalostettaessa ilmastonmuutokseen sopeutuvia viljelykasveja. Työssä tutkittiin lajin potentiaalia toimia geenivarantona tarkastelemalla kolmen Festuca rubra subsp. oelandica -populaation kloroplastien geneettisiä rakenteita mikrosatelliittien (cpSSR) avulla. Tutkimukseen sisällytettiin 58 alun perin kolmelta kasvupaikalta Öölannista kerättyä yksilöä.Tutkimus toimi lisäselvityksenä Luonnonvarakeskuksen ”Manipulating Grass – Fungal Endophyte Symbioses to Reduce Greenhouse Gas Emissions and Increase Soil Carbon Sequestration in Pastures of Finland, New Zealand, and the United States” -hankkeeseen liittyen. Kolmen öölanninpunanatapopulaation kloroplastien geneettisiä rakenteita tarkasteltiin alleelien muuntelua kuvaavien muuttujien, pääkoordinaattianalyysin, Bayesialaisen populaatiorakenneanalyysin sekä molekylaarisen varianssianalyysin perusteella. Pääkoordinaattianalyysin mukaan öölanninpunanatan kloroplastien geneettiset rakenteet eroavat merkittävästi muista pohjoiseurooppalaisista F. rubra-populaatioista. Analyysin mukaan öölanninpunantan kloroplastit olisivat jakautuneet viiteen geneettiseen ryhmään. Populaatioiden kloroplastien alleelien muuntelua kuvaavien muuttujien perusteella ei havaittu populaatioiden välisiä tilastollisesti merkitseviä eroja. Varianssianalyysin mukaan aineistossa havaittu muuntelu oli lähes yksinomaan yksilöiden välistä muuntelua. Populaatioden välillä ei havaittu varinassianalyysin perusteella tilastollisesti merkitseviä eroja. Populaatiorakenneanalyysin mukaan aineiston optimaalisin jaottelu saavutettiin jakamalla aineisto viiteen klusteriin. Klusterijako ei noudattanut oletettujen maantieteellisten populaatioiden jakoa. Klustereille suoritetun varianssianalyysin mukaan aineistossa havaittu muuntelu oli lähes yksinomaan yksilöiden välistä muuntelua. Klustereiden välillä ei havaittu varianssianalyysin perusteella tilastollisesti merkitseviä eroja. Käytettyjen menetelmien avulla aineistosta ei havaittu tilastollisia merkitsevää geneettistä ajautumista eikä aineistosta löydetty tilastollisesti merkitseviä osapopulaatioita. Öölanninpunanatan arvioitiin soveltuvan Festuca-sukuisten kasvien sekundääriseksi geenivarannoksi. Öölanninpunanatan mahdollinen polveutuminen eri jääkaudenaikaisesta kannasta kuin nykyiset viljellyt Festuca- ja Lolium-lajikkeet saattaa muodostaa kiinnostavan perinnöllisten ominaisuuksien varannon kasvijalostuksen kannalta. Lisätutkimusta kaivataan, jotta voidaan määrittää tarkemmin öölanninpunanatan sijainti Festuca-suvun taksonomiassa sekä lajin käyttömahdollisuudet viljelykasvien jalostuksessa. Alvarmaiden pirstaloituminen saattaa muodostaa uhan öölanninpunanatan muodostamalle hyödyntämättömälle geneettiselle varannolle.
  • Tenho, Laura (2010)
    Tutkimuksen tarkoituksena oli selvittää Opaskoirakoulun pentutestissä mitattavien ominaisuuksien perinnölliset tunnusluvut sekä niihin vaikuttavat tekijät. Aineisto koostui Opaskoirakoululla vuosina 1988–2008 pentutestin suorittaneista koirista (900 kpl). Suomen Kennelliito ry:stä saatiin sukulaisuusaineisto, johon täydennettiin rekisteriin kuulumattomat koirat. Tutkittavia ominaisuuksia oli 11 kappaletta: käyttäytyminen sylissä, luoksetulo, kontakti, taistelu, alistus, palautuminen, ääniherkkyys, käyttäytyminen pöydällä, seuraaminen, toimintakyky ja hermorakenne. Kaikki ominaisuudet arvostellaan pentutestissä valmiiden käyttäytymismallien mukaisesti. Aineiston esikäsittelyyn ja alustaviin analyyseihin käytettiin Microsoft Office Excel 2003-ohjelmaa sekä WSYS-L ja XWSYS-ohjelmistoja. Kiinteiden tekijöiden luokitteluun ja merkitsevyyden testaamiseen käytettiin WSYS-L ja XWSYS-ohjelmistoa. Varianssikomponentit sekä periytymisasteet laskettiin Restricted Maximum Likelihood (REML)-menetelmällä käyttäen VCE6-ohjelmistoa Tutkittujen ominaisuuksien periytymisasteiden arviot olivat alhaisia tai keskinkertaisia (h2= 0,07-0,39). Korkeimmat periytymisasteiden arviot olivat ominaisuuksilla alistus (0,39), toimintakyky (0,32) ja kontakti (0,31). Ominaisuuksien väliset geneettiset korrelaatiot olivat pääosin positiivisia. Poikkeuksen muodosti ominaisuus alistus, joka oli negatiivisesti korreloitunut palautumisen (-0,47) ja seuraamisen (-0,64) kanssa. Osa ominaisuuksista oli erittäin voimakkaasti korreloituneita (r > 0,8). Fenotyyppiset korrelaatiot vaihtelivat välillä 0,11–0,73 ja olivat geneettisiä korrelaatioita matalampia. Tämän tutkimuksen perusteella ominaisuuksissa käyttäytyminen sylissä, luoksetulo, kontakti, taistelu, alistus, ääniherkkyys, käyttäytyminen pöydällä ja toimintakyky on geneettistä vaihtelua ja sen perusteella niitä on mahdollista muuttaa haluttuun suuntaan jalostuksen avulla.
  • Nikkonen, Terhi (2009)
    Opaskoirakoulu kasvattaa itse suurimman osan tarvitsemistaan koirista. Tärkeimpinä jalostuskriteereinä pidetään terveyttä ja luonnetta, ulkomuodolla ei ole suurta merkitystä. Opaskoirakoulu testaa itse pentujen luonneominaisuuksia pentutesteillä ja koulutukseen tulevien koirien ominaisuuksia soveltuvuustesteillä. Soveltuvuustestien perusteella päätetään, jätetäänkö koira koulutukseen opaskoirakoululle vai ei. Lisäksi testien avulla pyritään valitsemaan koirat siitokseen. Tämän tutkimuksen tarkoitus oli selvittää opaskoirien soveltuvuustesteissä mitattavien ominaisuuksien periytymisasteiden arvioita ja ominaisuuksien välisiä yhteyksiä. Aineistona olivat Opaskoirakoululta saadut soveltuvuustestien tulokset vuosilta 1997-2008 (yhteensä 1682 testitulosta 465:ltä koiralta). Suomen Kennelliitosta saatiin lisäksi koirien sukulaistiedot sisältävä labradorinnoutajien rekisteritiedosto, jossa oli yhteensä 43 320 koiraa. Tutkittavia muuttujia olivat testiaineiston yksitoista eri luonneominaisuutta: temperamentti, keskittymiskyky, hermorakenne, toimintakyky, stressi, suhtautuminen toisiin koiriin, suhtautuminen ihmisiin, suhtautuminen liikenteeseen, paikka-arkuus, kovuus ja koulutettavuus. Kiinteiden tekijöiden tarkasteluun käytettiin WSYS-L- ja XWSYS - ohjelmistoja ja perinnöllisten tunnuslukujen arviointi tehtiin Restricted Maximum Likelihood -menetelmällä VCE6 -ohjelmaa käyttäen. Ympäristötekijöistä luonneominaisuuksiin vaikuttivat merkitsevästi sukupuoli, testi-ikä, syntymävuosi, syntymävuodenaika ja testaaja. Tutkittujen ominaisuuksien toistumiskertoimet ja periytymisasteiden arviot vaihtelivat ominaisuuksittain melko paljon. Korkeimmat toistumiskertoimet olivat koulutettavuudella (r = 0,58), paikka-arkuudella (r = 0,55) ja stressillä (r = 0,53). Alhaisin toistumiskerroin oli suhtautumisella liikenteeseen (r = 0,28) eli toistuvuudet kaikilla ominaisuuksilla olivat melko alhaisia tai kohtalaisia. Korkeimmat periytymisasteiden arviot olivat koulutettavuudella ja stressillä (h2 = 0,29). Alhaisimmat periytymisasteiden arviot olivat suhtautumisella liikenteeseen (h2 = 0,07), kovuudella (h2 = 0,08) ja paikka-arkuudella (h2 = 0,09). Luonneominaisuuksien väliset geneettiset korrelaatiot vaihtelivat tässä tutkimuksessa paljon, mutta olivat suurimmaksi osaksi korkeita ja positiivisia. Korkeimmat positiiviset geneettiset korrelaatiot olivat keskittymiskyvyn ja hermorakenteen, keskittymiskyvyn ja stressin, hermorakenteen ja stressin, keskittymiskyvyn ja koulutettavuuden, hermorakenteen ja koulutettavuuden ja stressin ja koulutettavuuden välillä (rg = 0,95 - 0,99). Alhaisimmat positiiviset geneettiset korrelaatiot olivat yleisesti paikka-arkuuden ja kaikkien muiden ominaisuuksien välillä (rg = 0,05 - 0,75) sekä kovuuden ja kaikkien muiden ominaisuuksien välillä (rg = 0,35 - 0,75). Alhaisissa positiivisissa geneettisissä korrelaatioissa myös keskivirheet olivat korkeita. Temperamentti korreloi negatiivisesti kaikkien muiden ominaisuuksien kanssa (rg = -0,10 - - 0,61). Myös suhtautumisen toisiin koiriin ja kovuuden välillä geneettinen korrelaatio oli epäsuotuisa (rg = - 0,18). Alhaiset periytymisasteiden arviot voivat johtua siitä, että soveltuvuustesti ei kuvasta koiran luonneominaisuuksia. Yksi syy alhaisiin periytymisasteisiin voi olla myös se, että ominaisuuksien takana onkin jokin laajempi luonneominaisuus, josta testissä nähdään vain viitteitä eri ominaisuuksia arvioitaessa. Myös korkeat geneettiset korrelaatiot viittaisivat siihen, että eri ominaisuuksia arvioitaessa arvioidaankin yhtä ja samaa laajempaa kokonaisuutta. Soveltuvuustesteissä arvioitavissa ominaisuuksissa oli geneettistä vaihtelua, joten niihin voidaan vaikuttaa jalostusvalintojen kautta.
  • Johnson, Christopher (2013)
    Experimental warming provides a method to determine how an ecosystem will respond to increased temperatures. Northern peatland ecosystems, sensitive to changing climates, provide an excellent setting for experimental warming. Storing great quantities of carbon, northern peatlands play a critical role in regulating global temperatures. Two of the most common methods of experimental warming include open top chambers (OTCs) and infrared (IR) lamps. These warming systems have been used in many ecosystems throughout the world, yet their efficacy to create a warmer environment is variable and has not been widely studied. To date, there has not been a direct, experimentally controlled comparison of OTCs and IR lamps. As a result, a factorial study was implemented to compare the warming efficacy of OTCs and IR lamps and to examine the resulting carbon dioxide (CO2) and methane (CH4) flux rates in a Lake Superior peatland. IR lamps warmed the ecosystem on average by 1-2 oC, with the majority of warming occurring during nighttime hours. OTC's did not provide any long-term warming above control plots, which is contrary to similar OTC studies at high latitudes. By investigating diurnal heating patterns and micrometeorological variables, we were able to conclude that OTCs were not achieving strong daytime heating peaks and were often cooler than control plots during nighttime hours. Temperate day-length, cloudy and humid conditions, and latent heat loss were factors that inhibited OTC warming. There were no changes in CO2 flux between warming treatments in lawn plots. Gross ecosystem production was significantly greater in IR lamp-hummock plots, while ecosystem respiration was not affected. CH4 flux was not significantly affected by warming treatment. Minimal daytime heating differences, high ambient temperatures, decay resistant substrate, as well as other factors suppressed significant gas flux responses from warming treatments.
  • Aho, Jani (2011)
    Tämän tutkielman tutkimusongelmana on operatiivisen tilaus-toimitusprosessin ominaispiirteiden nimeäminen sekä kyseisen prosessin kehittäminen sesonkityyppisessä liiketoiminnassa. Tutkimuksen apuna käytetään prosessin uudelleensuunnittelun keskeisiä teorioita. Tutkielman tavoitteena on luoda viitekehys, jota voidaan soveltaa kehitettäessä tai uudelleen suunniteltaessa tilaus-toimitusprosessia erityisesti sesonkityyppisen liiketoiminnan parissa. Empiirisessä osuudessa testattiin viitekehyksen soveltuvuutta käytäntöön todellisen kohdetapauksen avulla. Tässä tutkimuksessa kehitettävänä oli toimeksiantajayrityksen Oyj Stockmann Abp:n ja sen yhteistyökumppanin Itella Logistics Oy:n välinen tilaus-toimitusprosessi. Useat organisaatiot kehittävät toimintojaan vain omista näkökulmistaan. Tämä johtaa siihen, että toimitusketjun jokainen osa optimoi vain omia toimintojaan ja lopulta asiakkaan tarpeet alkavat unohtua eikä ketjun toimintaa enää kehitetä asiakaslähtöisesti. Tästä syystä tilaus- ja toimitusprosessin kehittäminen tulee perustaa asiakaslähtöiseen prosessin analysointiin. Tässä tutkimuksessa painopistealueita ovat asiakkaalle arvoa tuottavat ja tuottamattomat toiminnot sekä informaation välityksen varmentaminen kaikilla prosessin tasoilla. Seikkaperäinen analysointi vaatii poikkeuksetta prosessin mallintamista ja tämän tueksi laadittavaa prosessia selittävää käsikirjaa. Teoreettisena lopputuloksena on tässä tutkimuksessa syntynyt viitekehys, joka perustuu näihin lähtökohtiin. Empiirisessä osassa todettiin, että tilaus-toimitusprosessia voidaan tehostaa minimoimalla useiden tietojärjestelmien aiheuttamaa ylimääräistä työntekoa. Käytännössä ongelmat ilmenivät järjestelmien rajapinnoissa, jonka takia useat tilaus-toimitusprosessiin liittyvät transaktiot oli syötettävä järjestelmään erikseen. Manuaalinen ja ylimääräinen työsuoritus lisäävät virheiden syntymisen mahdollisuutta, kuluttavat resursseja sekä lisäävät ihmisten työmäärää. Tutkimuksen kirjoittajan näkemyksen mukaan ihanne olisi, jos kaikki transaktiot tehtäisiin ainoastaan kerran yhdessä järjestelmässä. Tämä vaatii kuitenkin informaation vaihdannan lisäämistä, operatiivisten toimintojen uudelleen suunnittelua ja yhteistyön lisäämistä prosessin eri tasoilla.
  • Nurminen, Jonne (2019)
    The thesis explores students' perceptions towards wood as construction and interior material. Wood construction plays an important role in the development of bioeconomy. Today, various construction methods and materials have been developed for wood, which in turn has generated new opportunities for urban construction of multistory buildings. Nowadays, the building regulations have become less strict and many wood construction pilot projects have been built through out Finland. To research students’ perceptions towards wooden constructions helps to understand what they as future home buyers prefer.                     The study employs quantitative research methods. An electronic survey was sent out to the residents of student housing operating in the Helsinki metropolitan area. A total number of 531 students responded to the survey. The results suggest that higher level of knowledge about wooden multistory buildings, childhood experience of living in wooden building as well as growing up in rural areas have a positive effect on the willingness to live in a wooden multistory building. Different purchasing habits also have influence on the attitudes towards wooden multistory buildings. Eco-ethical consumers have more positive perception of wooden multistory buildings than non eco-ethical consumers. However, their positive attitude does not lead to an increase in the willingness to pay extra. Respondents who consider themselves to be sensible consumers have high positive attitude and are willing to pay slightly higher rent for an apartment that is in a wooden construct. Wooden multistory buildings are recognized as eco-friendly more frequently by consumers who identify themselves as eco-ethical, sensible and hedonistic. The same view does not apply to consumers with loose consumption habits.
  • Lajunen, Anna (2016)
    The aim of this thesis was to define optimal packaging conditions for four fresh ready-to-cook and pre-cut vegetable mixes. The packaging conditions consisted of perforated and non-perforated film which were investigated in two different gas mixtures. One of the gas mixtures consisted of modified atmosphere which was chosen in advance and the other gas mixture consisted of normal atmosphere. The literature study focused on the negative influences of processing methods on the physiological properties of vegetables. The main principles of packaging solutions by which negative influences of fresh-cut produce could be minimized with were also mentioned. The main target of the experimental study was to examine if perforated films could be used for avoiding of in-package anaerobic respiration which is a common reason for vegetable spoilage. The respiration rates of the products were measured and with the results an optimally perforated film was defined for each product. The gas concentrations were measured electronically and the quality of the products were evaluated with sensory evaluations and microbiological determinations. Electronically measured gas concentrations were verified gas chromatographically and also the water vapour transmission properties of the films were studied. With perforated film and modified atmosphere gas concentrations remained most constant and they were mainly held in aerobic respiration level. With other packaging solutions very low oxygen levels and very high carbon dioxide levels were observed which was also noticed in the sensory evaluations where off-odours and off-flavours were discovered. With perforated film and modified atmosphere the growth of yeasts, molds and bacteria was smaller than with perforated film and normal atmosphere. The verification of the gas measurements was successful and gas concentrations which were measured both electronically and gas chromatographically were on the same range though minor differences in the accuracy of the results were discovered. The most optimal packaging solution for tested products was achieved with perforated film and modified atmosphere.
  • Assmuth, Aino (2015)
    This study applies two novel forest economic models to analyze the effect of optimal carbon storage on the choice between clearcuts and continuous cover forestry. Unlike previous studies, we determine the economically optimal management regime endogenously, by optimization. We study a policy where the society pays forest owners a Pigouvian subsidy for the carbon that is sequestered by the stand as it grows. The focus of our analysis is a subsidy system that also takes into account the carbon both stored in and released from wood products. In the first part of the thesis, the question of optimal carbon storage is studied using a continuous time biomass model that does not include any a priori assumptions on clearcuts vs. continuous cover forestry. We show analytically that subsidized carbon sequestration postpones thinning and increases optimal stand volume along the rotation. With high carbon price the shadow value of stand volume becomes negative. Numerical results show that carbon prices within a realistic range may switch the optimal management regime from clearcuts to continuous cover management. A higher interest rate can lead to a higher stand volume and a longer optimal rotation, which contrasts the results of the classic Faustmann model. Next, the question is studied applying a more detailed size-structured transition matrix model based on empirically estimated Scandinavian growth data. This approach produces a more accurate description of the complex dynamics of uneven-aged stands and optimization of harvesting activities. According to numerical results, thinning is invariably carried out from above, and the size of the harvested trees increases with carbon price. Optimal rotation age increases with carbon price, and moderate carbon pricing is sufficient to switch the management regime to continuous cover management. Optimal rotation age also increases with interest rate. Clearcut management is the more competitive, the more productive is the site type. Both models suggest that carbon storage has a significant effect on optimal forest management, and that it typically favors continuous cover forestry. Similar analysis on optimal carbon storage in forestry has not been presented before. We also discuss various carbon subsidy systems in the context of developing climate policy.
  • Jin, Qi (2013)
    The optimal harvesting for a set of even-aged Dahurian Larch (Larix gmelinii) stands located in Aershan area of the northeast of Inner Mongolia, China, are studied. The effects of catastrophic pest outbreaks (i.e. Siberian moth) on the optimal harvesting plan are also studied, and the comparison on these two cases, namely deterministic and stochastic, are analyzed. The simulation is based on an individual-tree diameter growth model, an individual-tree height model, and model for the tree mortality for the coming 5-year period. Combined with the simulation system, the optimization model modified from Hyytiäinen et al. (2005) is able to find the number of thinnings, intensity of thinning, type of thinning, subject to given rotation lengths. In even-aged management, the objective variable is the bare land value with 3.5% discount rate. In addition, a scenario approach is applied when simulating the effects of catastrophes, i.e., pest outbreaks. Stochasticity here is represented by a set of scenarios. The timing of an insect outbreak is random. In order to know the frequency of insect outbreak, an exponential model is applied. The numerical results indicate that the probability that an outbreak at epidemic level will occur within an interval of 5 years is about 0.39. Within a 10-year interval the probability is about 0.63. It is nearly certain that an outbreak at epidemic level occurs within 45 years. The optimal solutions are presented separately for deterministic and stochastic cases. For the deterministic case, the results indicate that high bare land values were associated with stands of high basal area, tree diameters and height. Typically, the higher the mean annual increment and the site quality, the higher the bare land value. Meanwhile, the results show that the optimal rotation may vary considerably (40-58 yrs) at 3.5% interest rate depending on the initial stand state. In the stochastic case, considering the effect of catastrophe of pest outbreak, numerical results show that the optimum roation is shortened and the mean values of bare land value are about 14.8% to 25.6% lower compared with the deterministic case.
  • Malmström, Miika (2013)
    This thesis studies the economically optimal timing of thinnings and final harvest on Costa Rican Tectona grandis plantations. Consequently this thesis studies the profitability of the plantations and makes a comparison to previous studies. Optimization is based on programming with AMPL with Knitro optimizing software. The objective function used is the Faustmann formula. Different rates of interest are used. The ecological functions used for the modeling were obtained from previous studies by Pérez and Kanninen (2005a). The economic data such as planting and thinning costs and log prices were obtained from a T. grandis plantation specialist. The results of the study show that the optimal harvesting regime in T. grandis plantations differs from what is suggested in literature. The main findings are that the optimal rotation length is shorter and both timing and intensity of the thinnings vary depending on the rate of interest used. In addition the maximized bare land values under optimal management regimes are notably higher than bare land values under previously suggested management regimes. The management regime is highly sensitive to the rate of interest used. The management regime is less sensitive to the changes in price than expected. This thesis suggests that the initial density of 816 ha-1 trees results into higher bare land values than 1111 ha-1 trees . However, the difference is minor and possible increase in silvicultural costs is not considered. In addition a simple test is carried out to see the possible effects on heartwood proportion growth to the optimal management regime. The shortcomings and possibilities to improve the model are discussed. It is noted that the price data for T. grandis is not coherent, and that the ecological model could be improved in order to increase its accuracy.
  • Rämö, Janne (2013)
    This study analyzes the optimal harvesting of single species uneven-aged Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.), and birch (Betula pendula Roth. and B. pubescens Ehrh.) stands, in addition to mixed species stands with all three species. The analysis is based on an economic description of uneven-aged forestry using a size-structured transition matrix model and a single-tree model. The optimization problem is solved in its general dynamic form using gradient-based interior point methods. Similar analysis on uneven-aged birch, Scots pine and mixed species stands in Nordic conditions has not been published. Increasing the harvesting interval decreases the average annual volume yield. Assuming natural regeneration, this suggests that volume yield is maximized by uneven-aged rather than even-aged management. The present value of stumpage revenues is maximized after saw timber and pulpwood prices, interest rate, and a 15-year harvesting interval are included. The economically optimal solution with a 3% interest rate produces an annual yield of 1.9, 5.5 and 2.9 cubic meters (m3) for Scots pine, Norway spruce, and birch respectively in single species stands at site with average productivity. At less productive sites, the mixed species stand is heavily dominated by Norway spruce regardless of interest rate. At more productive sites on the other hand, increasing interest rate increases species diversity. Both the optimal volume yield and net present value maximization solutions converge to unique species- and site-type-specific steady-states with constant harvests. The transition matrix model typically used in optimization studies is computationally less demanding than the single-tree model, but the differences in optimal solutions are more remarkable than earlier studies show. Additionally, it appears that the investmentefficient optimization model may result in steady-state solutions that significantly differ from the correct solutions.
  • Holma, Maija (2011)
    The objective of this thesis is to examine the economic effects in the conflict between grey seal population and the salmon fishery in the Baltic Sea. We will formulate a bioeconomic model which provides new insights on the optimal management of Atlantic salmon with respect to the effects brought about by the grey seal population. As the catch losses caused by seals have an effect on salmon fishery in Baltic, we will study how seal population affects the present value of the salmon fishery. The study considers the Finnish coastal trap net fishery. The bioeconomic model considers a scenario of sole salmon fishery and a scenario of salmon fishery affected by the grey seal population. On the basis of these scenarios, a seal compensation scheme is introduced. We can observe a significant economic seal-induced effect on the salmon fishery. The results suggest that the present seal compensation scheme emploid by the Finnish government is suboptimal. This thesis is part of the TARMO –project, in which the conflict between grey seal population and salmon fishery is studied using the methods of environmental economics.
  • Räsänen, Jenni (2013)
    The purpose of this study was to define economically optimal stand structures and harvesting cycles for uneven-aged Scots pine (Pinus sylvestris L.) in Finland. According to a recent proposal by Ministry of Agriculture and Forestry, uneven-aged management will be included in the new Forest Act as an alternative for future forest management in Finland. Uneven-aged management is also planned to be included in the Forest management practice recommendations by the year 2014. However, only little knowledge exists on optimal uneven-aged management in Finland, particularly on uneven-aged Scots pine. This thesis aimed at filling the gap in knowledge regarding economically optimal management of uneven-aged Scots pine. So far, economic studies on uneven-aged Scots pine have been conducted only in a static optimization framework, where optimal stand structure is constrained with a classic “reversed-J” diameter distribution, and transition cuttings are limited to one single harvest. In this work, stand structures and harvesting cycles were optimized for maximum volume yield and maximum stumpage revenues by applying both static and dynamic optimization. Until now, no dynamic optimization has been conducted on uneven-aged Scots pine. Static optimization was applied for different growth sites from mesic sites in Southern Finland (MT1300) to sub-xeric sites in Central Finland (VT1100). Mesic sites in Southern Finland were also optimized in a dynamic framework. A density-dependent individual tree model with latest ecological growth models was applied in optimization. The large-scale nonlinear problems were solved by means of numerical computing with discrete-time formulations. Present value of stumpage revenues was maximized applying 1% and 3% discount rates. Economically optimal harvesting cycle became 40 years in Southern Finland (site MT1300), and even longer at more northern and less fertile site types. Results imply that it is not economically optimal to manage Scots pine with a traditional selection method with short harvesting cycles, but rather with a heavy harvesting regime including low after cut basal areas. When maximizing present value of stumpage revenues, optimal after cut basal areas in Southern Finland were as low as 5 m2 (1% discount rate) and 3.2 m2 (3% discount rate) per hectare. A proposal of Ministry of Agriculture and Forestry suggests minimum after cut basal areas of 10–11 m2 per hectare for Southern Finland, which clearly exceed the optima of this study. Contrary to the existing results for uneven-aged Scots pine, economically optimal stand structure did not follow the classic reversed-J diameter distribution.
  • Nieminen, Emmi (2011)
    The aim of the thesis is to assess the fishery of Baltic cod, herring and sprat by simulation over 50 years time period. We form a bioeconomic multispecies model for the species. We include species interactions into the model because especially cod and sprat stocks have significant effects on each other. We model the development of population dynamics, catches and profits of the fishery with current fishing mortalities, as well as with the optimal profit maximizing fishing mortalities. Thus, we see how the fishery would develop with current mortalities, and how the fishery should be developed in order to yield maximal profits. Especially cod stock has been quite low recently and by optimizing the fishing mortality it could get recovered. In addition, we assess what would happen to the fisheries of the species if more favourable environmental conditions for cod recruitment dominate in the Baltic Sea. The results may yield new information for the fisheries management. According to the results the fishery of Baltic cod, herring and sprat are not at the most profitable level. The fishing mortalities of each species should be lower in order to maximize the profits. By fishing mortality optimizing the net present value would be almost three times higher in the simulation period. The lower fishing mortality of cod would result in a cod stock recovery. If the environmental conditions in the Baltic Sea improved, cod stock would recover even without a decrease in the fishing mortality. Then the increased cod stock would restrict herring and sprat stock remarkably, and harvesting of these species would not be as profitable anymore.
  • Airaksinen, Janne (2021)
    Aquaculture is seen as an answer to the future’s projected demand increase of seafood. This offers possibilities for the Finnish society to benefit economically. Globally, environmental concerns are set to the pressure the future demand, since the sector’s production is jointly linked to creating negative outputs, nutrient emissions. These problems are especially present in Finland, which’s offshore aquaculture production occurs geographically in one of the world’s most eutrophicated seas, the Baltic Sea. Finnish aquaculture regulation is currently a type of “command and control”, which is seen as one of the main reasons why the domestic production has decreased drastically in 21st century. Continuing to utilize feed quotas may not sufficient and incentivizing for the producers which creates need to review other possible economic instruments. This research studies the possibility of utilizing auctioned emission permits. The work contributes to auction theory of incomplete information games while adding Baltic Sea elements such as abatement costs to our analyzed model. This thesis addresses three questions: How can the chosen auction models support sustainable growth of aquaculture in economically efficient way? What is the level of optimal price floor? Which auction form is expected to create highest revenue surplus for the society? The policy maker is interested in assessing which of the chosen auction models is best allocation tool under present asymmetrical information. To combat the missing information on production values per kilogram of nitrate, Monte Carlo-simulation is utilized to generate values for the bidding producers. The analysis creates premise of including price floor in the mechanism designs to guarantee sustainability. The price floor guarantees that the value of allocated permit will be at least the size of our adopted abatement costs, which originate from certain mussel cultivation farm located in Sankt Anna, Sweden. The effects of two potential price floors are analyzed. First, which secures sustainability and second, which maximizes expected revenue surplus. Our modelled results follow the findings of the theory. All chosen auction designs are expected to create similar results in allocating the emission permits. To secure that the allocated permits are sustainable, and that the allocation maximize society’s revenue surplus, the social planner should implement price floor which is strictly higher than his personal valuation of the permit. This removes the possibility of auction being ex-ante efficient. Even though in the chosen model setting the price floor’s level was not dependent on the level of buyers, the social planner should not ignore the aspect of competition. By designing a mechanism that enables easy entry for bidders to participate, the auctions are expected to attract higher levels of competition which can create results that are closer to competitive markets. This can decrease the role of price floor, which may ease mechanism designing. To get more accurate results in the Finnish scene, more detailed information on possible domestic aquaculture production values is needed
  • Kanerva, Suvi (2023)
    Filamentous fungus Trichoderma reesei (teleomorph Hypocrea jecorina) is a crucial production organism for enzymes used in industrial applications, such as in feed, food, textile, and biofuel production, due to its ability to secrete high amounts of homologous and heterologous enzymes. Therefore, development of genetic tools to improve the properties of industrial T. reesei strains for even better production yields is essential. In this study, a polyethylene glycol mediated CRISPR-Cas9 transformation method for industrial T. reesei production strains was aimed to be optimised by testing an alternative Cas9 enzyme and varying the stoichiometry and total amount of Cas9 enzyme and single guide RNA in the ribonucleoprotein complex. Correct integration of the gene constructions in the obtained transformants was determined by colony PCR and Southern blot analysis. In addition, two selected background activity encoding genes, endoglucanase 6 and α-glucuronidase 1, were individually deleted from T. reesei xylanase production strain utilising the improved CRISPR-Cas9 transformation protocol. The effect of background activity deletions on the strain growth and protein production were analysed from culture supernatants by pH measurement, Bradford protein assay, sodium dodecyl sulfate polyacrylamide gel electrophoresis, and enzyme activity assays. An improved CRISPR-Cas9 transformation protocol for T. reesei was successfully established basing on high number of transformants and improved DNA integration fidelity. No negative effects were observed in the growth or protein production properties of the background activity deletion strains compared to the xylanase production strain. Thus, further cleansing of T. reesei secretome can be continued to refine the industrial production strains.
  • Riihimäki, Lotta Eveliina (2022)
    Severe acute respiratory syndrome coronavirus 2 is the pathogen behind COVID-19, a contagious disease that has caused millions of deaths since the beginning of the global pandemic in 2019. It is essential to gain more knowledge about the factors affecting viral entry and infection to understand prevention and treatment possibilities for the pathogen. Initially, an immunostaining assay was set up and showed that at eight hours post-infection, the virus had entered the target cells and started protein production. Five host genes of interest, identified by collaborators, were transiently silenced using small interfering RNA knockdown of cell lines. Once the silencing had been optimized, the effect on SARS-CoV-2 infection was monitored at eight and 24 h post-infection. The main pipeline used to follow the cell entry and replication was an extraction of total RNA, reverse transcription reaction followed by quantitative digital droplet polymerase chain reaction, showing the concentrations of the expressed target genes in the cells. The protocols of the transfection and ddPCR were tested and optimized to provide reproducible and reliable results. Out of six tested transfection reagents, DharmaFECT 2 showed the most effective results, decreasing the expression of target genes DDX3X and PDE4A by more than 75% after a 24 h incubation. The produced knockdown cells were infected with a produced and purified stock of SARS-CoV-2. Plaque assays were made from samples collected 24 hours post-infection, but no difference could be seen in the titer of the virus between the transfected cells and negative control cells. In conclusion, using digital droplet polymerase chain reaction to follow the effect of host gene knockdown on virus replication is possible as long as the initial gene expression is high enough.
  • Troupp, Minna (2022)
    The increasing use of antimicrobials causes a heavy pollution load on the environment and can enhance antimicrobial resistance of pathogenic bacteria, thus having a negative impact on human and animal health. Antibiotic concentrations in the environment are constantly monitored, however traditional chemical analyses fail to provide data on the bioavailability of antimicrobials. Whole-cell bacterial bioreporters have been developed to detect a wide variety of environmental pollutants including antimicrobials. These living, genetically engineered organisms can also be used for the measurement of the bioavailable fraction in a sample and thus bioreporters could give insights on the role of antimicrobial pollution in the dissemination of antimicrobial resistance. The aim of this study was to design and construct an improved bioluminescent bioreporter for detection of macrolide antibiotics. The mrx gene and the mph(A)R repressor gene were coupled with the mph(A) promotor of the macrolide resistance operon mph(A) and the reporter genes of the luciferase operon luxCDABE. The main objective was to determine whether Mrx, the hydrophobic and putative transmembrane transport protein of the macrolide resistance operon mph(A), would improve the sensitivity and reduce the induction time. Another aim was to optimize the use of three existing bioreporters with other macrolides than erythromycin, which was used earlier in testing their performance. The mrx-mph(A)R fragment was cloned into the pmph(A)luxCDABE vector, and the bioreporter plasmid was introduced to Escherichia coli strain DH10B. After verification of the construct pmph(A)luxCDABE-mrx-mph(A)R, the usability of the new whole-cell biosensor was compared against the three existing macrolide bioreporters with three different macrolide and lincosamide antibiotics, erythromycin, tylosin and clindamycin. The cloning of the new bioluminescent bioreporter for macrolides was performed successfully. However, the addition of erythromycin, tylosin or clindamycin to a suspension of E. coli DH10B(pmph(A)luxCDABE-mrx-mph(A)R) did not stimulate the expression of the lux genes. High concentrations of all three antibiotics triggered a light response with the existing bioreporters although the response was slow. The results indicated that further studies on the mrx gene and its encoded Mrx protein are still needed. The response of the mph(A) operon to other macrolide and lincosamide antibiotics than erythromycin was a positive and encouraging finding, since this enables detection of other synthetic macrolides than erythromycin as well as lincosamides with the existing bioreporters after optimization.
  • Wiik-Miettinen, Fanny (2018)
    Human gut microbiota is an important topic for many different disciplines. Various factors, e.g. antimicrobial drugs and diet, affect the development and balance of gut microbiota and its interactions with the host. Plant based carbohydrates that transit unabsorbed and undigested through the upper parts of gastrointestinal tract are an important source of energy for the colon bacteria. Some of colon bacteria produce short chained fatty acids (e.g. acetate, propionate, butyrate) from these carbohydrates. SCFAs provide a source of energy and regulate the cell growth and metabolism. The changes in the diversity and abundance of the SCFA producing bacteria have been linked to many gut related diseases. Studying gut microbiota with today’s analytical methods is still challenging. In this work the effects of dietary fibers on gut microbiota were monitored with a static, single vessel batch model. A batch model is typically developed for the quick high-throughput screening of samples. Fiber samples were processed in various ways to increase their solubility and thus fermentability. In this work butyrate producing bacteria, Akkermansia muciniphila and bifidobacteria were targeted. Enumeration was performed with selective growth media and quantitative PCR. Bacterial population was characterized by 16S rRNA based sequencing. To quantitate only viable bacterial cells from the sample matrix by qPCR, samples were treated with propidium monoazide (PMA), which after light activation inhibits the amplification of double-stranded DNA from dead and lysed cells. Since acidic SCFAs accumulate in the sample suspension, pH decreases clearly during the incubation in the static model. This leads to conditions which do not resemble the ones in the colon. Two different buffer solutions, pH adjustment and shorter incubation time were tested to overcome this challenge. The numbers of A. muciniphila and some of the butyrate producers decreased in acidic environment and the proportion of acid-tolerant bacteria was clearly increased and dominated the bacterial population. The optimization of PMA treatment for fecal suspension samples proved to be challenging due to the highly variable composition of sample matrixes. Dietary fibers were observed to cause different changes in bacterial population: the most soluble fibers caused greater decrease of pH and thus greater proportion of acid tolerant bacteria in the population.
  • Zhang, Yao (2012)
    The evolution of floral novelties involves activities of several transcription factors. The large Asteraceae plant family has inflorescences consisting of different types of flowers. TCP transcription factors have recently been reported to regulate this complex structure. Gerbera hybrida, a common ornamental crop, has been used as a model plant for flower developmental studies in Asteraceae. It can be genetically transformed; however, transformation is laborious and time-consuming. Calendula officinalis also belongs to the Asteraceae plant family. It has working micropropagation methods, and it grows and flowers faster than Gerbera hybrida. In addition, Calendula officinalis genes possess high sequence similarity to Gerbera hybrida genes and thus provide an opportunity for functional testing of large numbers of genes. For functional assessment, virus induced gene silencing (VIGS) is a rapid approach, as it circumvents the need to establish stable transgenic lines that requires efficient tissue culture and time-consuming whole-plant regeneration steps. In this study, twelve Calendula officinalis cultivars were tested for VIGS. Calendula showed potential as a new model for the Asteraceae plant family as all twelve different cultivars could be infected by tobacco rattle virus (TRV) via observing the fluorescence caused by pTRV2: GFP; and they all showed photobleaching silencing phenotype caused by PHYTOENE DESATURASE (GhPDS) gene from gerbera. Especially the cultivars „Touch of Red/Orange? and „Princess Orange? turned out to be the most efficient in silencing. Virus dynamics was successfully traced by fluorescence encoded by pTRV2: GFP construct. However, using the construct pTRV2: GFP: PDS, it was observed that the GFP gene could not be applied as a marker gene to indicate the silencing area, because fluorescence could not be observed in photobleaching area. The calendula PDS was also tested. More similar sequence corresponding to the plant?s endogenous gene could cause more visible silencing symptom, but quantitative polymerase chain reaction results showed no statistically significant difference on gene silencing efficiency between GhPDS and CoPDS fragments. VIGS was also tested for silencing of TCP domain transcription factor genes using gerbera specific gene fragments. It was observed that the VIGS approach was not suitable for functional testing of CYCLOIDEA-clade genes in Calendula officinalis as identification of the putative phenotypes was highly disturbed by variable inflorescence phenotype of the tested cultivar.