Multivariate NIR studies of seed-water interaction in Scots Pine Seeds (Pinus sylvestris L.)

This thesis describes seed-water interaction using near infrared (NIR) spectroscopy, multivariate regression models and Scots pine seeds. The presented research covers classification of seed viability, prediction of seed moisture content, selection of NIR wavelengths and interpretation of seed-water interaction modelled and analysed by principal component analysis, ordinary least squares (OLS), partial least squares (PLS), bi-orthogonal least squares (BPLS) and genetic algorithms. The potential of using multivariate NIR calibration models for seed classification was demonstrated using filled viable and non-viable seeds that could be separated with an accuracy of 98-99%. It was also shown that multivariate NIR calibration models gave low errors (0.7% and 1.9%) in prediction of seed moisture content for bulk seed and single seeds, respectively, using either NIR reflectance or transmittance spectroscopy. Genetic algorithms selected three to eight wavelength bands in the NIR region and these narrow bands gave about the same prediction of seed moisture content (0.6% and 1.7%) as using the whole NIR interval in the PLS regression models. The selected regions were simulated as NIR filters in OLS regression resulting in predictions of the same quality (0.7 % and 2.1%). This finding opens possibilities to apply NIR sensors in fast and simple spectrometers for the determination of seed moisture content. Near infrared (NIR) radiation interacts with overtones of vibrating bonds in polar molecules. The resulting spectra contain chemical and physical information. This offers good possibilities to measure seed-water interactions, but also to interpret processes within seeds. It is shown that seed-water interaction involves both transitions and changes mainly in covalent bonds of O-H, C-H, C=O and N-H emanating from ongoing physiological processes like seed respiration and protein metabolism. I propose that BPLS analysis that has orthonormal loadings and orthogonal scores giving the same predictions as using conventional PLS regression, should be used as a standard to harmonise the interpretation of NIR spectra

Electrochemically Modified Poly(dicyandiamide) Electrodes for Detecting Hydrazine in Neutral pH

A new technique for sensing nanomolar concentrations of hydrazine in water samples is reported. A screen-printed carbon electrode (SPCE) altered using an amine-azo functional group encompassing poly-(dicyandiamide) is used in this study. The modified electrode exhibits an enhanced activity toward hydrazine detection at a lower overpotential and broad linear scale between 20 nM and 1 mM, with an accurate sensitivity value of 0.1 nA mu m(-1) cm(-2). To the best of our knowledge, poly-(dicyandiamide)-modified electrodes exhibit one of the lowest limits of detection for any metal-free electrode that detects 6.7 nM (S/N = 3) of hydrazine. The method established sufficient selectivity and better recoveries. Finally, the poly-(dicyandiamide)-modified SPCE* is highly suitable for electrochemical determination of hydrazine in water samples from tap and lake

Green public procurement: an effective policy for reducing carbon dioxide emissions? : a study of cost-effectiveness, transaction costs and technological development

Green public procurement (GPP) can be used as an instrument to reduce carbon dioxide emissions, and consideration of environmental aspects within public procurement is becoming more common in Sweden and internationally. Two product groups that have been pointed out as especially important are transports and electricity, where the opportunities for public purchasers to reduce emissions are relatively large. This paper studies GPP which aims at reducing emissions, primarily of carbon dioxide, through environmental requirements within these two product groups. A theoretical analysis of cost-effectiveness, transaction costs and effects on technological development is performed, followed by a closer study of how these aspects appear in practice within GPP. The results indicate that a cost-effective allocation of reductions between the two product groups is most likely to be attained if the main part of emission reduction is achieved through environmental requirements on electricity. The cost for emission reduction within transports is relatively high, especially for heavy transports. For transportation services, more generally focused requirements on emission reductions could probably give greater environmental gains, but the existence of transaction costs steer the environmental requirements towards more technology specific types. A greater supply of environmentally labelled transports would probably facilitate the use of environmental requirements within this area. The label 'Bra Miljöval' electricity is the most common choice of electricity under GPP, and the transaction cost for public authorities can be kept comparably low in this case since a third party verifies real environmental performance. However, it can be questioned if Bra Miljöval is the best composition of environmental requirements if the main purpose is to reduce carbon dioxide emissions, since some techniques of electricity production with potentially low costs for emission reductions are not allowed. Public procurers have proportionately large opportunities to affect technological development within heavy transportation vehicles and strategic efforts within this area could therefore be recommended. The price premium paid for Bra Miljöval electricity does not seem to promote less developed electricity production techniques that are marketed at relatively high prices today. GPP programs more specifically directed at immature technologies might be necessary if technology development within renewable electricity production is desired. The main conclusion of the study is that the lack of statistics and follow-up of results make it difficult to perform more comprehensive environmental economic analysis of GPP. Systems on national level for regular follow-ups and reporting of results should therefore be prioritized in order to facilitate future studies and assessments.Miljöanpassad offentlig upphandling (MAOU) kan fungera som ett instrument för att minska utsläpp av koldioxid, och miljöhänsyn i offentlig upphandling blir allt vanligare i Sverige och internationellt. Två produktområden som pekats ut som speciellt viktiga är transporter och elenergi, där offentlig sektors möjligheter till utsläppsminsknigar är relativt stora. I denna uppsats studeras MAOU som syftar till att minska utsläpp, främst av koldioxid, genom miljökrav inom dessa två produktområden. En teoretisk analys görs med avseende på kostnadseffektivitet, transaktionskostnader och effekter på teknisk utveckling, följt av en närmare studie av hur dessa aspekter ser ut i praktiken inom MAOU. Resultaten tyder på att en kostnadseffektiv fördelning av utsläppsmål mellan de två produktområdena i dagsläget troligen uppnås om huvuddelen av utsläppsminskningen sker genom miljökrav på elleveranser. Kostnaden för utsläppsminskning inom transportområdet är relativt hög, speciellt för tunga transporter. Inom transporttjänsteområdet skulle troligen en tydligare fokusering på mer generella krav på utsläppsnivåer kunna ge större miljövinst, men förekomsten av transaktionskostnader styr miljökraven mot mer teknikspecifika former. Ett större utbud av miljömärkta transporter skulle troligen underlätta användningen av miljökrav inom detta område. Bra Miljöval el är det vanligaste valet inom MAOU av el, vilket ger förhållandevis låga transaktionskostnader eftersom en tredje part kontrollerar uppfyllelse av miljökrav. Det kan dock ifrågasättas om kriterierna för Bra Miljöval är den bästa utformningen av miljökrav om huvudsyftet är minskade utsläpp av koldioxid, eftersom vissa produktionstekniker med potentiellt låga kostnader för utsläppsminskningar inte tillåts. Offentliga upphandlare har förhållandevis stora möjligheter att påverka den tekniska utvecklingen av tunga transportfordon och strategiska satsningar inom detta område kan därför vara lämpliga. Den prispremie som betalas för Bra Miljöval el verkar inte bidra till att främja mindre mogna elproduktionsteknologier som idag har förhållandevis höga marknadspriser. Mer specifikt inriktade upphandlingsprogram kan behövas om teknisk utveckling inom förnyelsebar elproduktion är en del av målsättningen. Studiens huvudsakliga slutsats är att bristen på statistik och uppföljningar i dagsläget gör det svårt att utföra mer övergripande miljöekonomiska analyser och utvärderingar av MAOU. Nationella system för regelmässig uppföljning och inrapportering av resultat bör därför prioriteras för att underlätta framtida studier och utvärderingar

The Drosophila Pax6 paralogs have different functions in head development but can partially substitute for each other

There are two Pax6 genes in Drosophila melanogaster; eyeless (ey) and twin-of-eyeless (toy), due to a duplication, which most likely occurred in the insect lineage. They encode transcription factors important for head development. Misexpression of either toy or ey can induce formation of ectopic compound eyes. Toy regulates the ey gene by binding to an eye-specific enhancer in its second intron. However, Toy can induce ectopic eyes also in an ey− background, which indicates a redundancy between the two Pax6 copies in eye formation. To elucidate to what extent these two genes are interchangeable, we first generated toy-Gal4 constructs capable of driving the Pax6 genes in a toy-specific manner. Genetic dissection of the promoter proximal region of toy identified a 1,300-bp region around the canonical transcription start that is sufficient to drive toy expression in embryonic brain and eye primorida and in larval eye-antennal discs. We find that exogenous expression of toy can partially rescue the lethality and eye phenotype caused by lethal mutations in ey and vice versa. We therefore conclude that Toy and Ey, to some extent, can substitute for each other. Nevertheless, the phenotypes of the rescued flies indicate that the two Pax6 genes are specialized to regulate defined structures of the fly head

En utvärdering av de skogliga vattenplaneringsverktygen NPK+ och Blå målklassning med avseende på vattenkvalitet och vattenkemi

Intresset för vattenfrågor har ökat efter införandet av EU:s ramdirektiv för vatten (vattendirektivet, 2000/60/EG) och inneburit att vattenvård och hänsynstagande till vatten inom skogsbruket fått större fokus. Målet med vattendirektivet är att alla vatten inom EU (Europeiska Unionen) ska erhålla en god kemisk och ekologisk status innan år 2015 samt att ingen försämring får ske. Skogsbruket kan i vissa fall ha negativa effekter på vattenmiljöer. NPK+ och Blå målklassning är två skogliga vattenplaneringsverktyg som har utvecklats för att öka vattenhänsynen i skogen. Verktygen utgörs av ett inventeringsprotokoll som bedömer vattenmiljöns naturvärde (N), påverkan (P), känslighet för skogsbruk (K) samt plusvärden (+). Med stöd av NPK+-protokollet utförs sedan en subjektiv indelning av Blå målklasser. Blå målklasser hjälper skogsägare att optimera hänsynen till vatten och visar också vilka åtgärder som bör göras för att utveckla eller bibehålla ekologiska värden i vattendraget. Huvudsyftet med denna studie var att (1) utvärdera verktygens förmåga att fånga in vattenkvalitet med avseende på vattenkemi och (2) undersöka hur väl verktygen bidrar till vattendirektivets mål. För ändamålet inventerades 173 skogskällvattendrag, belägna i Dalarna och sydvästra Sverige, med hjälp av verktygen NPK+ och Blå målklassning. Bedömningen av vattenkvalitet med NPK+-protokollet och Blå målklasser jämfördes med kemisk analys av vattenprover och vattenkemisk status av försurning och övergödning enligt EUs vattendirektiv genom parvisa korrelationer och multivariat statistik. Resultatet pekade på att vattenkemin i de två regionerna skiljde sig åt, med mindre mänskligt orsakad försurning, lägre nivåer av TOC, totalkväve, totalfosfor, absorbans, turbiditet och slamhalt samt högre pH i Dalarna, vilket också fångades upp av många parametrar i NPK+-protokollet. Variationen inom respektive region var dock liten, vilket gjorde att skillnader i vattenkemiskt tillstånd var svårare att avgöra med hjälp av protokollet i fält, men enstaka samband existerade också på regional nivå. Vid den subjektiva konverteringen från NPK+-protokollet till Blå målklasser var många samband med vattenkemiskt tillstånd svåra att upprätthålla. Status med avseende på försurning och övergödning visade starkare samband med avrinningsområdets karaktär och kunde inte förklaras utifrån verktygen. Förmågan att bedöma försurning och övergödning med NPK+-protokollet kan förbättras genom mer tillförlitliga underlag. Verktygen bidrar till vattendirektivets mål genom att motverka övergödning och genom vidareutveckling kan verktygen anpassas till regional nivå och på så sätt bidra än mer till att uppnå vattendirektivets mål. Som helhet bedöms verktygen ha stor potential för att förbättra vattenhänsynen i skogsbruket.The interest in water related issues has increased after the introduction of the Water Framework Directive (WFD, 2000/60/EC) and more attention has been given to water management in forestry. The objective of the WFD is that all waters within the EU (European Union) should achieve a good chemical and ecological status before 2015 and also that no degradation of water quality should occur within the timeframe. Forestry can sometimes have adverse effects on aquatic environments. BIS+ and Blue targets are two water planning tools that have been developed to facilitate water consideration in forestry. BIS+ consist of a simple checklist that assesses a stream section’s biodiversity (B), human impact (I), sensitivity for forestry (S) and added values (+). With support from the BIS+ checklist a subjective classification of Blue targets is performed. The Blue targets should help forest owners to optimize environmental considerations to forest streams and also show the actions needed to develop or maintain ecological values in the stream. The main purpose of this study was to (1) evaluate the tools' ability to assess water quality regarding water chemistry and (2) examine how well the tools contribute to WFD objectives. For the purpose 173 headwater streams, located in Dalarna and southwestern Sweden, were assessed using the tools BIS+ and Blue targets. The assessment of water quality and water chemistry with the checklist were compared with chemical analyzes of water samples and surface status of acidification and eutrophication according to the WFD using pairwise correlations and multivariate statistics. The results indicate that the water chemistry in the two regions differ, with less anthropogenic acidification, lower levels of TOC , total nitrogen, total phosphorus, absorbance, turbidity and suspended solids and higher pH in Dalarna. This is also shown in the assessment of many characters in the BIS+-checklist. However, the variation within each region is small and the differences in water chemistry between streams are more difficult to determine with the help of the BIS+-checklist, although some correlations are to be found. The subjective classification from the BIS+-checklist to blue targets suggests that the correlations between water chemistry and characters in the BIS+-checklist are difficult to retain. Status regarding acidification and eutrophication showed stronger correlation with catchment characteristics and could not be explained by the tools. The ability to assess acidification and eutrophication with the BIS+-checklist can be improved by more reliable data. The tools contribute to WFD objectives by preventing eutrophication and with further development, the tools can be adapted to the regional level, and at the same time contribute even more to the WFD objectives. In total, BIS+ and Blue targets have a great potential to improve the consideration of waters in forest management

Competition for forest fuels in Sweden

This thesis project focuses on the need for better tools for analyzing competition for forest fuels in Sweden, in particular how policy measures may influence the market and involved actors in different regions of Sweden. Raw materials from the forest have for long constituted important inputs in the Swedish forest industry. Today some of these raw materials are increasingly used as inputs also in bioenergy production, largely driven by bioenergy promoting policies, and there are signs of increased competition for forest fuels which may have various and uncertain effects on the industries in question. The thesis project explores the possibilities to adapt previously used forest sector equilibrium models into a new model suitable for analysis of Swedish forest fuel markets, called the Swedish Forest Sector Trade Model (SFSTM). The approach takes into account regional differences in supply and demand for 23 types of products produced and/or used by eight types of producers, plus consumers, in five different regions (four Swedish and one international). The project contributes with the novelty of an economic partial equilibrium model of the Swedish forest sector that includes regional trade and bioenergy production. After extensive data collection and fitting of the model setup according to Swedish circumstances, the model is programmed and solved in GAMS software. The model is calibrated and then tested as a tool for analysis by implementing scenarios that imply shifts in energy demand and introduction of a tax on forest fuels used in bioenergy production. The project results are primarily of interest in understanding the models functionality in a Swedish context, in particular with regards to the availability of regionalized data and related implications for the model setup. The thesis concludes in several key issues and recommendations on further steps to be taken if this type of model should continue to be developed in Sweden, such as; the need for better data on extraction and processing cost of logging residues, the need for better data on exogenous input costs in forest industries, and how the model results are affected by the choice of geographic scale of (trading) regions and related assumptions on transport cost functions

Gasification of pure and mixed feedstock components: Effect on syngas composition and gasification efficiency

The aim of this work was to investigate whether the use of individual tree components (i.e., stem wood, bark, branches, and needles of spruces) as feedstocks during oxygen blow gasification is more efficient than using mixtures of these components. Experiments were performed at three oxygen levels in an 18-kW oxygen blown fixed bed gasifier with both single and mixed component feedstocks. The composition of the resulting syngas and the cold gas efficiency based on CO and H-2 (CGE(fuel)) were used as response variables to evaluate the influence of different feedstocks on gasification performance. Based on the experimental results and data on the composition of similar to 26000 trees drawn from a national Swedish spruce database, multivariate models were developed to simulate gasifier performance under different operating conditions and with different feedstock compositions. The experimental results revealed that the optimal CGE(fuel) with respect to the oxygen supply differed markedly between the different spruce tree components. Additionally, the models showed that co-gasification of mixed components yielded a lower CGE(fuel )than separate gasification of pure components. Optimizing the oxygen supply for the average tree composition reduced the CGE(fuel) by 1.3-6.2% when compared to optimal gasification of single component feedstocks. Therefore, if single-component feedstocks are available, it may be preferable to gasify them separately because doing so provides a higher gasification efficiency than co-gasification of mixed components

Kretsanalysinstrument för envarvig spole

The thesis work was given on the request from ÅR Carton to produce a circuit able to measure current, voltage, frequency and the phase shift between the current and voltage in a one turn coil. The measured data was also to be sent to a computer for later use in analyzing the data. The most important question was which method to use to measure the current in the coil, suggested alternatives were between using a Rogowski coil or a Hall Effect sensor. The method was required to have minimal physical impact. Due to this, a Hall Effect sensor appeared to be the best choice. The measurement of the voltage was done by just measuring over the inductor, the resulting voltage was estimated as too high for the circuit to handle so a voltage divider was introduced to lower the voltage to a more appropriate level. The first tests of measuring the voltage and current showed that filters needed to be introduced to reduce some noise that was present in the signals. Both of the signals were converted to a DC signals with the help of RMS-to-DC converters. To measure the frequency and the phase shift of the sine waves a Schmitt trigger, the filter from before wasn’t enough to remove the noise completely so a comparator wasn’t sufficient to use, was introduced to convert each of the waves into square waves, which were then sent to an exclusive-or gate. These signals were then sent to a microcontroller which A/D converted the DC voltages and calculated the frequency and phase shift from the square wave of the exclusive-or gate. The microcontroller then sent the digital values and calculated data to a storage station using serial communication. Circuit diagrams were produced during the course of the project with the help of Microsoft Visio and Eagle Cad. A design for a printed circuit board was produced with Eagle Cad for the microcontroller and serial communication section of the circuit which was produced

Potential of NIR spectroscopy to predict amygdalin content established by HPLC in intact almonds and classification based on almond bitterness

[EN] In this study, 360 intact almonds, half sweet and half bitter, were assessed by near-infrared (NIR) spectroscopy to predict amygdalin content (established by high performance liquid chromatography (HPLC)) and by applying partial least squares (PLS) to the spectral data. After optimising amygdalin extraction and chromatographic conditions, the amygdalin contents found by HPLC were not detected or below to 350 mg kg-1 for sweet almonds, and between 14,700 and 50,400mg kg 1 for bitter almonds. The intact almond spectra resulted in good predictions of amygdalin content with R2p of 0.939 and RMSEP of 0.373. Almonds were correctly classified into sweet and bitter by linear discriminant analysis (LDA), quadratic discriminant analysis (QDA) and PLS-DA, with sensitivity and specificity values higher than 0.94 for evaluation set samples. Based on these results, it can be concluded that NIR spectroscopy is a good non-destructive alternative to be used as an automatic in-line classification system by food industry.Victoria Cortes Lopez thanks the Spanish Ministry of Education, Culture and Sports for the FPU grant (FPU13/04202). The authors wish to thank the cooperative Agricoop for kindly donating the almonds.Cortes-Lopez, V.; Talens Oliag, P.; Barat Baviera, JM.; Lerma-García, MJ. (2018). Potential of NIR spectroscopy to predict amygdalin content established by HPLC in intact almonds and classification based on almond bitterness. Food Control. 91:68-75. https://doi.org/10.1016/j.foodcont.2018.03.040S68759