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(2018)Att byta ut en del av vallensilaget till ärt-havrehelsädesensilage skulle kunna höja det näringsmässiga värdet för mjölkkors foderstater och vara ett alternativ till att köpa in proteinfoder. Den kemiska sammansättningen och smältbarheten för ärt-spannmålshelsädesensilage har varierat en hel del i olika studier, och särskilt påverkats av fodrets ärthalt. Grovfoder av baljväxter minskar behovet av kvävegödsling och har i de flesta studier resulterat i lägre metanutsläpp per kg torrsubstansintag eller per kg mjölk eller kött jämfört med vallgrovfoder. Målet med avhandlingen var att utvärdera hur väl ärt-havrehelsädesensilage lämpar sig i en foderstat, med eller utan rapsmjöl, för mjölkkor. Ett experiment utfördes med en gasproduktionsmetod in vitro. Foderstaterna bestod av torkade foder, endera vallgrönfoder, ärt-havregrönfoder eller både vall- och ärt-havregrönfoder som grovfoder, samt korn eller korn och två olika mängder rapsmjöl som kraftfoder. Två olika ärt-havregrönfoder, från år 2015 och år 2016, med ärthalterna 900 respektive 250 g/kg ts, undersöktes. Ärt-havregrönfodrens råproteinhalt var 157 respektive 106 g/kg ts och NDF-halten var 345 respektive 558 g/kg ts, för ärt-havre 2015 och ärt-havre 2016. Kraftfodrets andel av foderstaterna var 40 %, och rapsmjölets andel 0, 5,5 eller 11 %, i torrsubstans. Foderstaternas kemiska sammansättning analyserades, och foderstaternas inverkan på smältbarhet, användbart råprotein i tunntarmen (uCP) och olika våmjäsningsprodukter, så som ammoniak-N, flyktiga fettsyror och metan mättes. Användning av ärt-havregrönfoder försämrade klart foderstatens NDF-smältbarhet. Rapsmjölstillsatsen ledde till ökad halt av ammoniak-N i våmmen och större andel uCP16. Dessa parametrar påverkades mest av foderstatens råproteinhalt, medan grovfodertypen hade mindre inverkan. Foderstaterna med både ärt-havre 2015 och vall ledde till högre andel uCP16 än foderstaterna med endera ärt-havre 2015 eller vall. Kvävenedbrytningen skedde ändå delvis olikartat för ärt-havre och vall. Resultaten gällande de molära andelarna propionsyra och ättiksyra stämde inte överens med en del tidigare studier med baljväxter, i och med att andelen ättiksyra steg och andelen propionsyra sjönk när vallen ersattes med ärt-havre. Detta avspeglades i ökad metanproduktion när ärt-havre 2015 ersatte vall, dock inte i fallet med ärt-havre 2016. Sett till fodervärdet bör det dock eftersträvas hög ärthalt i ärt-havregrönfoder. Enligt dessa resultat kunde ärt-havrehelsädesensilage väl användas i mjölkkors foderstater, komplettering med rapsmjöl kunde ändå vara nödvändig.
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(2020)In the beginning of lactation, dairy cows experience a negative energy balance that can lead to ketosis. Ketosis is a metabolic condition that affects production and health, and can occur clinically or subclinically. The aim of this thesis was to investigate the association of ketosis and the cow’s breed and parity to milk production and composition. Also the association of predicted NEFA, dry period, rest period and days open with ketosis, breed and parity was investigated. The data was acquired from ProAgria’s Maidosta Maitoon (MaMa) project, where 12 dairy farms had during two test periods tested milk’s BHB (β-hydroxybutyrate) concentration during the first seven weeks after calving. On each period, 20 animals per farm were participating and each animal’s production information came from Mtech Digital Solutions. NEFA values were predicted by using the milk fatty acid composition determined with mid-infrared (MIR) spectrometry. The animals were divided into four different groups based on the milk BHB concentration (≤ 50, ≤ 100, ≤ 200 and ≥ 500 µmol/L). The most common breeds on the farms, Ayrshire and Holstein, were included in the analysis. Parity was investigated by first comparing heifers with cows and then by dividing the animals into four different parity groups (1., 2., 3. and ≥ 4.). The milk production and composition were analyzed with repeated measures for the periods of 60 and 305 days in milk. The dry period, rest period and days open were analyzed with Friedman’s non-parametric variance analysis. The ketosis group did not affect daily milk yield during 60 or 305 days. Milk fat concentration was higher and protein concentration lower in groups with higher milk ketone concentration. Holstein cows had higher milk production than Ayrshire cows, and older cows had higher production than heifers. Milk production and ECM up to 60 days tended to increase by parity, peaking in the third parity group and decreasing in the fourth or higher lactation. Milk protein yield increased in Ayrshire cows in association with higher milk BHBA concentration, whereas the opposite was observed in Holstein cows (interaction breed x ketosis group, P = 0,045). The interaction between breed and parity tended to affect protein content, Ayrshire heifers had lower protein content than Holstein heifers but Ayrshire cows had higher protein content than Holstein cows. The predicted NEFA concentration increased by ketosis group. Holstein cows tended to have greater predicted NEFA concentrations than Ayrshire cows and heifers had significantly greater predicted NEFA concentrations than cows. Ketosis group affected the length of the dry period; the dry period was the longest in the third ketosis group. In addition, the length of the dry period was increased by parity. Ayrshire had shorter rest period and less days open than Holstein. Based on the results from this study, there was a difference between breeds on how ketosis affects milk production and milk composition. Further research is needed to understand the basis of the difference between breeds.
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Inverkan av mjölkproduktion, foderdiet och ensilage på förekomst av våmacidos och ketos hos mjölkkor (2024)Subacute ruminal acidosis (SARA) and ketosis are metabolic diseases that occur in milking cows and affect milk production and feed efficiency. The aim of this thesis was to investigate how milk production and composition of diet and silage affected the occurrence of ruminal acidosis and ketosis in milking cows. Data was provided from six dairy farms with milking robots. From the farms, data was collected from milking test-day results, rumination and performance reports from robot. The farms took samples from silage regularly and feeding plans were updated continuously. Three farms with Gea and three farms with Lely milking robots participated in the study. Data from these farms were collected and sorted in separate Excel-files and analysed with logistic regression analysis to obtain the odds ratios for ruminal acidosis and ketosis and to compare the farms with each other. The odds ratio for ruminal acidosis increased with increasing milk production and concentrate allowance for both Lely- and Gea farms. When dietary and silage crude protein concentration increased the odds ratio for ruminal acidosis decreased in Gea farms but not in Lely farms. An increase in dietary concentrate proportion increased and increase of dietary fibre decreased the odds ratio for acidosis in both farm groups, while an increase of dietary starch and silage fibre increased the odds ratio only in Gea farms. The odds ratio for ketosis decreased when milk production increased in Lely farms. The odds ratio for ketosis increased in Gea farms but decreased in Lely farms when concentrate allowance increased. An increase of dietary starch decreased the odds ratio for Gea-farms but not for Lely-farms. The odds ratio for ketosis decreased for both groups when rumination time increased. There were differences in the odds ratio for ruminal acidosis and ketosis between the farm groups for milk production, rumination time and for various descriptive variables regarding the composition of feeding diet and silage. This suggests that in addition to production level and feeding composition there are other factors influencing the risk of ruminal acidosis and ketosis in farms.
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(2015)Antibiooteille vastustuskykyisistä eli resistenteistä bakteereista on tullut maailmanlaajuinen ongelma, joka on vakavuudeltaan verrattavissa pandemioihin. Tautia aiheuttavien bakteerikantojen vastustuskyky vaikeuttaa infektioiden hoitoa ja voi aiheuttaa pahimmillaan jopa kuolemantapauksia. Bakteerien antibioottivastustuskyky on antibioottiresistenssigeeneihin perustuva ominaisuus, joka on yleistynyt antibioottien käytön seurauksena sekä tautia aiheuttavilla bakteereilla että vaarattomilla ympäristöbakteereilla. Erityisen ongelmallisia ovat liikkuvissa geneettisessä elementeissä sijaitsevat antibioottiresistenssigeenit, joissa on DNA:n aktiiviseen siirtymiseen vaadittavia geenejä. Liikkuvissa geneettisissä elementeissä sijaitsevat resistenssigeenit siirtyvät erittäin tehokkaasti bakteerien välillä, jolloin resistenssigeenien leviäminen ympäristöbakteereilta tautia aiheuttaville bakteereille aiheuttaa maailmanlaajuisesti oleellisen riskin ihmisten terveyden kannalta. Maisterintutkielmassani kehitettiin IPCR:ään (engl. inverse PCR) pohjautuva menetelmä antibioottiresistenssi-geenejä ympäröivien geenien tutkimiseen. Antibioottiresistenssigeenejä ympäröivien alueiden avulla voitiin päätellä, sijaisivatko resistenssigeenit liikkuvassa geneettisessä elementissä, ja sitä kautta arvioida antibioottiresistenssigeenien leviämisriski. Liikkuvissa geneettisissä elementeissä on antibioottiresistenssiresistenssigeenien lisäksi muita kullekin liikkuvalle geneettiselle elementille tyypillisiä geenejä, jotka voitiin monistaa käyttämällä kehitettyä IPCR-menetelmää. Menetelmää käytettiin kalanviljelylaitoksen bakteerien sul1- ja tetM-resistenssigeenejä ympäröivien geenien tutkimiseen. IPCR:ää ei ole aikaisemmin sovellettu liikkuvien geneettisten elementtien ja antibioottiresistenssigeenien tutkimiseen ympäristönäytteillä. IPCR:ää ja uuden sukupolven PacBio-sekvensointimenetelmää käyttämällä onnistuttiin monistamaan ja sekvensoimaan useita sul1- ja tetM-geenejä sisältäviä liikkuvia geneettisiä elementtejä, mikä osoitti, että menetelmä sopii antibioottiresistenssigeenien liikkuvien geneettisten elementtien tutkimiseen ympäristössä. Kaikki sul1- ja tetM-geenit sijaitsivat liikkuvissa geneettisissä elementeissä, minkä vuoksi geeneillä on suuri siirtymisriski kalankasvattamolla esiintyviltä ympäristöbakteereilta ihmisille tai kaloille tautia aiheuttaville bakteerikannoille. tetM-geenit sijaitsivat Tn916-tyyppisissä transposoneissa tai sul1-geenin kanssa samassa integronissa. sul1-geenit sijaitsivat puolestaan integroneissa, joissa oli lisäksi muita resistenssigeenejä, ja myös geenejä jotka aiheuttavat vastustuskykyä terveydenhuollossa tärkeille antibiooteille, joita ei käytetä kalanviljelyssä. Yksi sul1:n kanssa samasta liikkuvasta elementistä löytyneistä geeneistä oli mahdollisesti uudentyyppinen blaoxa-β-laktaamiantibioottiresistenssigeeni. Uuden mahdollisen resistenssigeenin löytyminen osoittaa, että IPCR soveltuu hyvin myös uusien liikkuviin elementteihin liittyneiden resistenssigeenien etsimiseen. Maisterin tutkielmassani kehitetty IPCR-pohjainen menetelmä, joka perustui perinteisiin molekyylibiologisiin tekniikoihin eikä vaatinut kalliita reagensseja tai laitteita, osoittautui käyttökelpoiseksi ympäristössä esiintyvien antibioottiresistenssigeenien siirtymisriskin arvioimiseen. Menetelmää voitaisiin jatkossa käyttää edullisesti ja helposti antibioottiresistenssigeenien ja -geenejä sisältävien liikkuvien geneettisten elementtien monitorointiin ympäristössä, myös silloin kun antibioottiresistenssigeenit eivät vielä ole levinneet sairaalaympäristöön. Tällöin ihmisen toiminta voi vielä vaikuttaa haitallisten antibioottiresistenssigeenien leviämiseen tautia aiheuttaville bakteereille.
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(2015)Gelatin-based confections are one type of gummy confections. Their main ingredients are water, sucrose, glucose syrup and gelatin, which causes gel-like texture. The literature review focused on the raw materials, the manufacturing process and the properties of gelatin- and starch-based gummy confections. The aim of this study was to find out how invert sugar, when it replaces sucrose and glucose syrup, affects structural properties and short-term shelf life of gelatin-based confections. In addition, changes in the sensory quality were observed. In the experimental research, the gelatin-based confections were manufactured on a laboratory scale according to simplex-centroid mixture design, where the total sugar content was constant, but sucrose, glucose syrup and invert sugar mass fractions were varied. Measurements for the samples were rheological properties, sugar content and dry matter content of confection paste and mechanical properties (hardness, stickiness and relaxation parameters), dry matter content, water activity and water sorption of confections. In addition, a few samples were manufactured with coloring and flavoring agents for sensory observation. The results were analyzed with the PLSR (Partial Least Squares Regression). Finnsugar Ltd.'s product development department offered the topic of this study and raw materials, but all the experiments were carried out in the Department of Food and Environmental Sciences in the University of Helsinki. The PLSR model contained five components, and the coefficient of determination R2 was 74.1%, the adjusted R2 was 63.3% and the coefficient of prediction Q2 was 43.6%. The model determined all response variables well, but predicted some of them poorly. Almost all response variables regression models were statistically significant at 5% significance level, but some of the models were incomplete (plof<0.05). The variables important in projection (VIP) in the PLSR model were mass fraction of invert sugar, mass fraction of glucose syrup and their interactions with mass fraction of sucrose. The PLSR model was best for rheological properties of confection pastes and mechanical properties of confections, and poorest for water activity and dry matter content of confections. Even at low mass fraction of invert sugar viscosity of confection paste decreased. Invert sugar also reduced hardness of confections, and speeded up their structures recovery after compression. Sensory observation shows the positive effects of invert sugar, such as softness of structure and stronger taste. The present study showed that the sugars have interactions, which also affect properties of the gelatin-based confections, and invert sugar content alone is not the significant factor. Based on the results of this study it seems that invert sugar affected stronger most of the response variables if it replaced relatively more glucose syrup than sucrose.
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Investigating airborne virus transmission in public spaces using a non-pathogenic model virus phi 6 (2021)The COVID-19 pandemic of 2019 has had a huge impact on the hospitality industry, decreasing production by 35.4% in Q4 of 2020. To keep the industry functional, new safety solutions have to be studied and developed for mitigation of the pandemic. In this study, airborne transmission of viruses in an indoor space was studied, and air purifiers and space dividers were tested as potential intervention methods against SARS-CoV-2 by using a non-pathogenic model virus phi 6. Filtered air purifiers were found to work as a possible solution for the mitigation of viruses spreading through aerosols in public spaces such as restaurants, however, the positioning of the devices is crucial, as the air flow to them may increase the concentration of viruses locally. Space dividers were found to increase the possibility of infection via aerosols. Other types of air purifiers were also tested: an ionizer prototype and a hydroxyl radical emitting unit, of which the ionizer prototype proved to be efficient in reducing the virus concentrations in the air. Most importantly, it was confirmed that enveloped viruses resembling coronaviruses are capable of spreading via aerosol transmission indoors.
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(2023)Semliki Forest virus (SFV) is a well-studied model virus of medically important mosquito-borne alphaviruses, like chikungunya virus and Sindbis virus. SFV replicates within membrane invaginations called spherules at the host plasma membrane, facilitated by the virus-encoded nsP1 protein. The objectives of this MSc thesis were to identify candidate host proteins interacting with nsP1 based on previous proteomics work and develop a screening workflow to identify stable nsP1 interactors. The overarching aim is to improve our understanding of the roles of host proteins in spherule formation and replication complex functions. The screening workflow involved knockdown assays to assess the antiviral and proviral effects of potential host interactors, followed by cell viability assays for toxicity assessment. Selected promising hits were further investigated for protein interaction with nsP1, which required cloning for mammalian expression and tagging with Myc epitope. Knockdowns resulted in several statistically significantly proviral and antiviral host factors, and all the knockdowns were non-toxic to the cells. Among the significant proviral hits, four promising candidate host proteins were cloned and expressed. Pull-down assays did not reveal stable interactions, suggesting transient or indirect interactions between these host proteins and nsP1. The lack of co-localisation with SFV replication complex supported this finding. This work sheds light on possible transient or indirect interactors of nsP1. The screening workflow effectively identified protein-protein interactions and can be applied to screen additional proteins. Future studies should employ methods suitable for studying transient interactors to gain further insights. This would enhance our understanding of key host proteins in SFV spherule formation and replication, potentially leading to novel antiviral therapies targeting alphavirus replication.
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(2020)Mycosporine-like Amino Acids (MAAs) are small, secondary metabolites, with the ability to absorb UV light. They are produced by cyanobacteria to act as a sunscreen. The aim of this study was to catalogue MAA genetic and chemical diversity in strains of the cyanobacterial genus Nostoc. MAAs were detected in 21 of the 68 Nostoc strains using LC/MS. Fifty four different MAAs were detected across the Nostoc strains. Glycosylated MAAs were detected in 17 of the 21 strains with hexose being the most commonly occurring sugar. Surprisingly, two structurally distinct MAAs were detected from a lichen symbiont strain, Nostoc sp. UHCC 0926. Chemical analysis detected a theoretical methylated and glycosylated variant (m/z 583, C23H39N2O15), and a suspected tri-core variant (m/z 757, C34H53N4O15) with three chromophore rings as opposed to one which is typically found. The glycosylated MAA was predicted to have a hexenimine core which was methylated and had two hexose moieties. The tri-core consisted of 2 aminohexenone cores, one on either side of a central aminohexenimine core. An 8.3 Mb draft genome sequence was obtained to identify the MAA biosynthetic gene cluster responsible for the biosynthesis of these two unusual MAAs. This resulted in the detection of two gene clusters mysA-B-C1 and mysD-C2-C3. This gene cluster organisation was compared with those of other Nostoc strains. The gene cluster organization in Nostoc sp. UHCC 0926 was unique because it was the only strain to have two gene clusters and three mysC genes despite one of the other Nostocs having the ability to produce a tri-core MAA. The strain was cultured and harvested to allow for the extraction and purification of the target MAAs. The tri-core MAA structure was confirmed by NMR. However only a putative structure for the glycosylated MAA was made. The UV absorption spectrum of the tri-core MAA had an absorption maximum at 312 nm while the glycosylated and methylated MAA had an absorption maximum at 336 nm. The investigation into the MAA production of UHCC strains expands the known chemical and genetic diversity of MAAs produced by strains of the Nostoc genus.
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(2019)OBJECTIVES and RESEARCH QUESTION. Human parechovirus 3 (HPeV3) is a (+)ssRNA icosahaedrally symmetric virus which causes meningoencephalitis and sepsis in children and neonates. As it causes the most severe symptoms among parechoviruses it is attracting more attention (4). Currently there are no approved broad treatment strategies against parechoviruses, however recent research by Rhoden et al., 2017, reported the antiviral activity of posaconazole (PSZ) against HPeV3 in cell culture. Posaconazole is an antifungal drug approved for use against Candida and Aspergillus infections. It targets lanosterol-14alpha-demethylase and prevents the production of ergosterol, a lipid vital for fungal membranes not present in mammalian cells (24). In mammalian cells PSZ accumulates at the endoplasmic reticulum (ER) and binds to the oxysterol-binding protein (OSBP) and Niemann-pick type C1 (NPC1) (59, 28, 30). The drug may affect cellular components and thusly block parechoviral infection or could bind to the viral capsid. METHODS. To test viral capsid-binding hypothesis PSZ activity was tested in a range of concentrations against two HPeV3 isolates and HPeV1 Harris in Vero and HT29 cell lines. HPeV3 isolate 152037 was purified on a CsCl step gradient and imaged by cryo electron microscopy (cryo-EM). Single particle analysis was done in Scipion (40) and acquired density maps visualized in UCSF Chimera (49). Atomic model of a different isolate of HPeV3 (PDB ID: 6GV4, 16) was changed at 6 sites and fitted to density maps from this work in Coot (52). Maps were subtracted in search of density that would represent PSZ. RESULTS. PSZ was effective against both HPeV3 isolates at 1 μM in Vero cells when added to the virus prior to infection, however not in HT29 cells. At higher concentrations (>10 μM) PSZ formed crystals which limited the concentration that can be used for cryo-EM. In order to test the hypothesis of PSZ being a capsid binder 3 datasets were collected, HPeV3 control, HPeV3+DMSO and HPeV3+PSZ (4 μM) with final resolutions after single particle analysis of 3.3 Å, 3.9 Å and 3.4 Å respectively. Subtraction of maps yielded no difference that would represent PSZ. DISCUSSION and CONCLUSION. PSZ does not appear to be a capsid binder although it appears to work early in the infection. Absence of PSZ density in HPeV3+PSZ density map could be due to low saturation and images containing PSZ were filtered out in image processing. Another possibility is low affinity of PSZ for the capsid. As PSZ binds various membranes it is possible that it blocks HPeV3 infection by targeting cell components. Additional experiments could be performed in the future in order to provide insight into which stages of infection PSZ affects.
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(2013)In this study the financial returns related to smallholders’ return on investments in Eucalyptus globulus (Labill.) were analyzed for the Kentai sub-watershed in the Tana-Beles Watershed Monitoring and Evaluation project in Amhara Regional State, Ethiopia. This was accomplished by reviewing the inputs used in activities carried out by smallholders. A cross-sectional survey was conducted to analyze the inputs and outputs realized by different household investment choices. The Net Present Value (NPV), Equivalent Annual Income (EAI), Benefit-Cost Ratio (BCR), and Internal Rate of Return (IRR) of investments were estimated. The NPVs ranged between -65,750 Br/ha (-2,670 €/ha) and 1,389,920 Br/ha (56,350 €/ha) over a 30-year period at interest rates of 10, 20 and 30%. The EAIs corresponded with the NPVs, and were used in comparison with agricultural crops. In almost all cases EAI of E. globulus exceeded that of other crops. BCRs varied from 0.13 to 118 at an interest rate of 10%. The maximum IRR achieved was 383% and the minimum was ?4%. The average IRR was 60%. Additionally, the financial returns for revenue from sales, cost savings from household consumption and reinvestment were analyzed in five scenarios. Reinvestment in rental homes proved the most lucrative return, followed by use of poles for home construction, for fuelwood consumption, and, finally, only for sale. Additional use of wood at home or reinvestment of earnings was more profitable than only selling poles on the local market. The study found that most households have profitable financial returns from investment in E. globulus. Those households with negative returns may plant for non-monetary benefits or carry out non-profit maximizing behaviour due to personal, cultural, or other reasons not captured in this analysis. It is believed that continued adoption of E. globulus will plateau in the near future. This study suggests a number of measures that could be implemented to increase returns and reduce costs including: co-operative development, recognition of smallholder plantations by government, and tenure security improvements.
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(2016)Combined heat and power (CHP) generation is potentially an attractive entrepreneurship lane in rural Finland. The country’s climate, infrastructure and political commitments are making such businesses more favorable. The latest technological advances in cogeneration further facilitate the use of discussed energy technologies. The present study examines the net present values (NPVs) and internal rates of return (IRRs) of investments in various energy generation technologies with entrepreneurial prospects (sales of heat and electricity). CHP, wood boiler, oil boiler and ground source heat pump (GSHP) systems were studied at two production scales (detached rural house and farm). For wood-fueled energy systems own forest fuel availability was considered. Renewable energy subsidies were applied for eligible technologies. The study found that with current technologies and renewable energy subsidies, the heat and power production mix can be more favorable than heat alone at comparable scales. Own wood fuel resources made investments in energy generation more viable. The profit margins, however, remain very tight and CHP entrepreneurship is still likely to be undertaken by enthusiasts. Operation and maintenance costs were identified as some of the most significant hindrances for adoption of wood-fueled CHPs. For other energy alternatives, price of fuel almost solely determined the value of investments. The study also discusses a host of climate and energy production issues pertaining to CHP technologies.
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(2021)Oat β-glucan is a non-starch polysaccharide, and it is well-known that oat β-glucan provides physiological functionalities, such as reducing glycemic response. It is proposed that the reduction of glycemic response is due to the elevation of digesta’s viscosity in the intestinal tract, which is attributed to the viscosity generated by β-glucan. An increase in viscosity of digesta is assumed to hinder starch digestion, thus reducing glucose absorption. However, it is not known whether viscous β-glucan or β-glucan gel causes such physiological responses. Thus, the aim of this Master’s thesis was to study the effects of viscous β-glucan on in vitro starch digestion. The in vitro starch digestibility method was adjusted to suit the viscous β-glucan. The hypothesis was that sample containing oat β-glucan would hinder starch hydrolysis compared to the sample without oat β-glucan. Viscosity and viscoelasticity of wheat starch were analyzed to ensure that the concentration of the wheat starch used was appropriate for the study. The viscosities of oat β-glucan solutions at different concentrations were also measured. The in vitro starch digestibility result was evaluated by measuring the concentration of starch hydrolysis product. Viscosity and viscoelasticity tests of wheat starch showed that 4% wheat starch was suitable in the starch digestibility study. The viscosities of various concentrations of oat β-glucan exhibited pseudoplastic flow behavior. In vitro starch digestibility showed that oat β-glucan slowed down the starch hydrolysis. Calcium contained in oat β-glucan was found to enhance the activity of α-amylase, resulting in a higher concentration of the starch hydrolysis product. 2160 µg/g Ca2+ was added to all samples in order to compensate for different Ca2+ concentrations in each sample. The maximum Ca2+ concentration that 1 U α-amylase could utilize was 98 µg/g Ca2+. The results of this study confirmed that the viscous oat β-glucan hindered the starch digestibility compared to the sample without oat β-glucan and calcium ions played a role in starch digestibility.
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(2017)Dextrans are polysaccharides and mainly produced from lactic acid bacteria, which have great values in industrial applications. Dextrans with different molar mass and branches have different applications. In this thesis, the effects of different reaction factors on the molar mass and composites of dextrans had been studied. Weissella confusa VTT E-90392 dextransucrase was used to synthesize dextran with sucrose as substrates. The effects of sucrose concentration, enzyme concentration, reaction time, temperature and pH on dextran macromolecular properties were detected. Sucrose concentration, enzyme concentration and reaction time were selected as the most influential factors for the subsequent response surface modeling to analyze how they affect dextran properties, according to experimental design. 18 reaction conditions were conducted and the product mixtures containing dextran were analyzed by HPSEC. The effects of the three reaction factors on dextran production were also studied. The predictive contour plot showed that dextran conversion was positively proportional to the enzyme concentration and increased in the early stage, but decreased in the late stage. In the preliminary study of the effects of various factors on dextran profile, two or three main dextran size populations eluting at different volumes were found in HPSEC analysis. The 1st dextran size population (eluted around 10.5 ml) had the highest Mw ranging from 7 × 107 to 2 × 108 g/mol. The 2nd dextran size population (eluted at around 12.5 ml) had Mw ranging from 2 × 107 to 4×107 g/mol. Besides, there seemed to be a 3rd dextran size populations (eluted at 16.2 ml to 17.5 ml) and the Mw was within the widest range (5 × 106 g/mol to 1.3 × 107 g/mol).We kept the samples' 4 factors constant and one factor changed and compared the effect of each factor. Under conditions: low sucrose, dextransucrase concentration, low temperature, low pH or short reaction time, the amount of the 2nd dextran size population was in equal or higher amount than the 1st one and 3rd one hardly appeared. On the contrary, the 1st size population became predominant over 2nd one, and the 3rd one started to form. In the modeling experiments, the overall effects of reaction time, sucrose concentration and enzyme concentration on the molar mass and amounts of different dextran size populations were studied. In our study, as the sucrose and enzyme concentration increased, the 2nd dextran size population decreased. The amount of 3rd one was positively proportional to the sucrose and enzyme concentrations. At the early stage of reaction, the amount of 3rd one was positively proportional to the reaction time, but the amount of 3rd one was negatively proportional to the reaction time. We hypothesize that as the reaction proceeds, 2nd dextran size population can be elongated into the 1st population. It was not clear whether the 2nd dextran size population could combine with themselves to form 1st one (internal insertion) or the 2nd one could only be inserted with D-glucosyl units one by one (external insertion). At the end of synthesis, dextran can be degraded possibly by hydrolyzing D-glucosyl units externally, because there should be more than 3 dextran populations if the dextran was internally broken. Based on the above results, it might give some new clue about the process of dextran synthesis and the way the dextran was hydrolyzed.
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(2014)Non-digestible oligosaccharides possess important physicochemical and physiological properties. They have gained great attention because of their potential prebiotic properties. The oligosaccharides have wide food industrial applications as dietary fibers, sweeteners, humectants, and possible weight controlling agents. In this thesis, cloned Weissella confusa VTT E-90392 dextransucrase was used to catalyze the synthesis of oligosaccharides (acceptor products) by acceptor reaction, when sucrose was the glucosyl unit donor. Maltose acceptor reaction was selected to analyze the effects of the concentrations of sucrose and maltose, as well as the dosages of dextransucrase on maltose acceptor products. Other acceptor reactions were also evaluated, with primary lactose and cellobiose acceptor products being purified and partially characterized by MS/MS. Concentrations of sucrose and maltose, as well as their interactions were the most important factors regarding isomalto-oligosaccharides production. The production of overall oligosaccharides could be increased by increasing sucrose and maltose concentrations. Lactose, cellobiose, other disaccharides and trisaccharides could be acceptors for W. consufa dextransucrase. In combination with the structures from previous publications, 2-a-Dglucopyranosyl-cellobiose and 2-a-D-glucopyranosyl-lactose were probably the primary products for cellobiose and lactose, although one trisaccharide synthesized by lactose acceptor reaction remains unknown. In order to verify the characterization, NMR spectroscopic analysis is needed for further study. In conclusion, W. consufa dextransucrase is capable of catalyzing oligosaccharides synthesis, and acceptor reactions would be promising methods in producing prebiotic oligosaccharides.
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(2024)Background: Recent findings in adults and children suggest that vegetarians, and particularly vegans, are at risk of iodine deficiency. As an increasing number of individuals adhere to plant-based diets, it is important to investigate the current iodine nutrition in children and adults. Aim: The aim was to examine whether iodine intake from food and supplements differs in children and adults who follow vegan, vegetarian, or omnivore diets, and to describe the main sources of iodine in these diets. Furthermore, the objective was to investigate the median urinary iodine concentration and determine whether these diets are associated with inadequate iodine status. Materials and methods: Cross-sectional data for children (n=73) and adults (n=79) were drawn from participants in the MIRA2 study. Iodine intake from food and supplements was assessed using a 3-day food record and a background questionnaire. The iodine status was assessed using spot urine samples. Results: Among children, there were no between-group differences in total iodine intake from food and supplements. In adults, vegetarians had a significantly lower total iodine intake than vegans and omnivores, but only vegan adults had a median urinary iodine concentration below 100 μg/L. Iodine supplements were the main sources of iodine in the vegan diet for both children and adults, whereas grain products were an important source of iodine regardless of diet. No association was found between plant-based diets and inadequate iodine status, defined as a median urinary iodine concentration below 100 μg/L. Conclusions: This study found no association between plant-based diets and inadequate iodine status. However, sufficient iodine intake may be compromised in adults who follow vegan and vegetarian diets. These results highlight the importance of iodine supplementation in the vegan diet.
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(2013)The City of Helsinki relies strongly on the use of fossil fuels as its main energy source. Coal power with high level of emissions covers one third of the city’s energy production. To mitigate the effects of climate change, the city should stop using coal and replace it with the use of renewable energy. The goal of this thesis is to find a way for Helsinki to replace coal by 2030 with energy efficiency improvements and distributed renewable energy. Thesis was an assignment from WWF Finland and it is a part of urban energy campaign called Seize your Power. First of all, the local circumstances have to be understood. This gives a basis to Geothermal Scenario that is formed to replace coal. First step of the Scenario is to reduce the demand of coal power by energy efficiency improvements in buildings. Next, a set of locally functional renewable energy sources is formed based on decreased demand. Main energy source of the Scenario is geothermal energy but also biomass,solar and wind power are utilized. The Geothermal Scenario is then evaluated with costbenefit analysis. Results of Cost-Benefit Analysis show that the net present value (NPV) is negative in short, medium, and long term. The values vary between -200 million and circa -3 billion euros. In the sensitivity analysis, the effects of the changes in prices of emission permit, coal, and bio-SNG as well as discount rate were estimated. The length of time horizon had a huge impact on the results. Non-market values were not included in the analysis.
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(2018)Background: The role of parents in the development of children’s long term eating patterns and food preferences is significant. Although the role of fathers in child upbringing is known to have changed during the past decades, are studies conducted about the role of fathers in food parenting still lacking. Aims: The aim of this study is to increase knowledge about the role fathers have in food parenting and the factors that affect fathers’ food choice motives (FCMs) when making food choices for their children. We examined the nutrition knowledge of fathers, how much they participate in food parenting, what is the food choice motives for fathers when selecting foods for their child and are the importance of different motives explained by the studied factors. Material and methods: The empirical part of the study was conducted by a quantitative study method using a web questionnaire. The FCMs of 281 fathers of 2-6-year-old children was examined by a modified version of Steptoe’s et al. Food Choice Questionnaire (FCQ). In addition, fathers reported how many times during a normal week they eat together with their children and how often they carry responsibility about the buying and/or preparation of food for their child. Fathers were also asked to answer 12 questions measuring their nutrition knowledge. The FCMs were conducted through principal component analysis. The relationships between variables were examined by non-parametric statistical tests, Spearman -correlation test and linear regression analysis. Results: Health, sensory amiability, nutrition quality and convenience were the key FCMs for fathers in this study. They ate together with their child in average 3 times a day. 77 % of the respondents answered that they carry often or always responsibility of the organization of food for their child. The averaged percentage of answers in line with the recommendations in the nutrition knowledge questions was 73 %. The higher education level was associated with a better nutrition knowledge. The higher importance of the health motive was associated with fathers younger age, living in the metropolitan region and the bigger participation in feeding of the child. The higher the fathers’ nutrition level was, the less their food choices for children was driven by what the child wanted and more by the nutrition level of the food. Conclusion: The fathers in this study are actively involved in the food parenting of children. The FCMs of fathers were for most part in line with previous studies conducted with parents and according to previous literature the FCMs of fathers in this study are supporting the development of healthy eating patterns of children. The causality of the association between nutrition knowledge and the child mood and wants -motive would be an important next step in examining if, by increasing fathers nutrition knowledge, it is possible to drive them into making healthier food choices for their children.
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(2021)Traktorien nostolaitteen sivurajoittimia on yritetty hydraulisoida 1970-luvulta lähtien. Kiuruvetinen yritys Piippo Hydraulic on kehittänyt Farmiventtiili -nimisen erikoisventtiilin, joka kykenee ohjaamaan sivurajoittimia yhdessä ja erikseen. Lisäksi traktorin ohjausjärjestelmiä varten on kehitetty ISO 11783-standardi, jossa määritellään traktorin, työkoneiden ja niiden ohjainlaitteiden välinen väyläliikenne. Tämä mahdollistaa eri valmistajien laitteiden kytkemisen yhteen ja samaan ohjaus- sekä tietoväylään. Tässä maisterintutkielmassa tehtiin prototyyppi Farmiventtiilin ISOBUS-pohjaisesta ohjauksesta. Farmiventtiilin ohjaus toteutettiin Epec Oy:n toimittamalla ohjauslaitteella, Multitool-konfigurointiohjelmalla, CodeSys PLC-ohjelmointiympäristöllä sekä IsoDesigner-käyttöliittymän suunnitteluohjelmalla. Näillä työkaluilla suunniteltiin virtuaaliterminaalille käyttönäkymä, laitteen ECU:lle toimintalogiikka sekä 3D-tulostamisen avulla prototyyppiasteen monitoimiohjain. Laitteelle tehtiin myös valmius väyläpohjaiselle ohjaukselle traktorin oman tai muun valmistajan hallintalaitteiden kautta AUX-N -standardiosan mukaisesti. Prototyypissä testattiin myös nostolaitteen työntövarren, kallistajan ja sivurajoittimien anturointia ja siihen pohjautuvaa automatiikkaa. Lopputuloksena saatiin prototyyppiasteen ohjausjärjestelmä, jossa on toteutettu nämä toiminnallisuudet. Työn edetessä havaittiin, että sinällään yksinkertaiseen venttiiliin voidaan mahduttaa ohjelmoitavuuden ansiosta runsaasti sellaisia toiminnallisuuksia, joita yksinkertaisella analogiohjauksella ei voida saavuttaa. ISOBUS:ssa toimiva ohjausyksikkö kykenee toimimaan myös muiden venttiilijärjestelmien siltalaitteena, jos järjestelmää on laajennettava. ISOBUS:n avulla toteutettu ohjaus alentaa kustannuksia, kun omia ohjainlaitteita ja kaikkia antureita ei tarvita väylällä valmiiksi olevien laitteiden ansiosta.
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(2015)Tutkielman tavoitteena oli selvittää kirjallisuustutkimuksena ISOBUS-väylän hyödyntämismahdollisuuksia. Hyödyntämismahdollisuuksia etsittiin sekä peltotöidenteon aikaisista hyödyistä, että jälkikäteen työn analysoinnin hyödyistä sekä hyödyistä valmistauduttaessa seuraavaan työtapahtumaan ja seuraaviin vuosiin. Työn aikaiset hyödyt jakautuvat kahteen eri luokkaan. Sellaisiin, mistä on apua viljelijälle sekä työkoneen ja traktorin autonomisen toiminnan lisäämisen hyötyihin. Viljelijälle apua on mm. polttoaineenkulutusmittarista, joka näyttää reaaliaikaista polttoaineenkulutusta myös hehtaaria kohti, työkoneen toimintaa mittaavista anturitiedoista tai pienestä mutta tärkeästä asiasta eli työkoneen työtuntilaskuriin perustuvasta huoltomuistutuksista. Työkoneen ja traktorin autonomisuuden lisäämisellä on mahdollista tehdä jopa täysin ilman ihmistä toimiva traktori. Väylän avulla työkone voi ohjata traktoria mm. muuttamaan työnopeutta tai työsyvyyttä ja kun väylälle lisätään vielä GPS-ajouraopastin niin traktori osaa myös ohjata itseään pellon sisällä gps-paikkatiedon perusteella. Työn analysoinnissa väylän isoimmat hyödyt ovat tietojen siirtäminen suoraan tietokoneelle viljelykirjanpitoon, jolloin viljelijän ei tarvitse pitää paperisia muistiinpanoja työsuorituksista sekä analysoitavien tietojen määrän runsas kasvu. Viljelijä pystyy runsaan tietomäärän avulla kotonaan etsimään pellolta ongelmakohtia ja selvittämään johtuuko pellon vajavainen kasvu pellon huonosta kasvukunnosta vai viljelytoimenpiteistä. Tietokoneella pystyy myös valmistelemaan työtä tekemällä esimerkiksi paikkakohtaisen lannoituskartan esimerkiksi satokartan avulla tai määrittämällä ajourat pellolle niin, että pelto saadaan työstettyä mahdollisimman nopeasti ja tehokkaasti ilman päällekkäisajoa. Tietoja voi siirtää tietokoneelle ja sieltä takaisin väylälle joko reaaliaikaisesti mobiilidatan tai langattoman internetin avulla tai määräajoin laittamalla muistitikun väylälle ja siirtämällä tiedot sen avulla tietokoneelle. Väylän standardisointi on vielä kesken, mutta joka tapauksessa se mahdollistaa monipuolisen teknologian käytön ja hyödyt viljelyssä.
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