12 resultados para D-glucose and N-acetylglucosamine

em Doria (National Library of Finland DSpace Services) - National Library of Finland, Finland


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Tutkielman tavoitteena on tutkia yrityksen tutkimus- ja tuotekehitystoiminnan (T&K) vaikutuksia yrityksen suorituskykyyn. Tutkielmassa tarkastellaan myös lyhyesti T&K- toimintaa osana yrityksen toimintoja ja ympäristöä. Tutkielman empiirisessä osassa tutkitaan poikkileikkausmenetelmää käyttäen T&K- menojen vaikutusta yrityksen kasvuun, kannattavuuteen ja osakkeen hintaan (tuottoon). Tutkielman empiirinen osa toteutettiin keräämällä tilinpäätös- ja osaketiedot 65 yritykselle vuosilta 1999-2005. T&K- menojen vaikutusta yrityksen kasvuun, kannattavuuteen ja osakkeen tuottoon tutkittiin eri aikavälejä käyttäen, jotta mahdolliset syy-seuraussuhteet voitaisiin luotettavasti osoittaa. Tutkimustulokset osoittavat, että yrityksen T&K- menoilla on positiivinen vaikutus yrityksen kasvuun ja kannattavuuteen ja,siten tulokset tukevat kahta tutkimuksen päähypoteesia. Yrityksen T&K- menoilla ja osakkeen tuoton välillä ei kuitenkaan käytetyllä aineistolla empiiristä yhteyttä löytynyt, joten kolmas päähypoteesi hylättiin.

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Under de senaste åren har intresset för utnyttjandet av förnybara resurser kraftigt ökat. I samband med detta utgör kolhydrater en viktig del av den tillgängliga förnybara biomassan och den har därefter blivit föremål för ett stort intresse inom hållbar kemi. Sockeralkoholer är en särskilt viktig grupp av molekyler som vanligtvis erhålls ur kolhydrater och som har mångsidiga tillämpningar som t.ex. lågkalorihaltiga sötningsmedel. Forskningen i doktorsarbetet omfattar hydreringen av naturligt förekommande sockerarter L-arabinos, D-galaktos, D-maltos och L-ramnos till respektive sockeralkoholer. Dessa sockeralkoholer kan användas bl.a. som hälsosamma sötningsmedel på samma sätt som xylitol. Grunden för detta arbete består av hydreringsexperiment som utfördes på en dispergerad ruteniumkatalysator i syfte att studera bildningskinetiken av de motsvarande sockeralkoholerna. Reaktionerna genomfördes vid temperaturer mellan 90 och 130 °C och vätetryck mellan 40 och 60 bar. Under dessa betingelser var det möjligt att åstadkomma sockeromvandlingar upp till 100 %. Reaktionshastigheterna modellerades matematiskt. Konkurrerande kinetiska modeller som baserades på Langmuir-Hinshelwood-konceptet föreslogs för att beskriva reaktionerna. Parametrar i hastighetsekvationerna bestämdes därefter genom icke-linjär regression. Dessa modeller kunde väl förutsäga hydreringsreaktionernas förlopp och de kan följaktligen användas för design av industriella anläggningar. Ytterligare hydreringsexperiment med sockerblandningar genomfördes för att fördjupa kunskaper i kinetik och reaktionsmekanismer av sockerhydreringen. Studierna genomfördes med syntetiska sockerblandningar av L-arabinos och D-galaktos (de viktigaste komponenterna i hemicellulosan arabinogalaktan). Fullständig omsättning uppnåddes med utmärkta selektiviteter som överskred 95 % och dessutom inverkade varken temperatur eller vätetryck på reaktionens förlopp på något oväntat sätt. Antagandet av konkurrerande adsorption för en samtidig reduktion av båda sockermolekylerna gav en kinetisk modell som noggrant beskrev de experimentella resultaten. Idén om att utforska potentiella sätt att påskynda bildningen av sockeralkoholer ledde till utföringen av hydreringsexperiment med L-arabinos och D-galaktos i närvaro av ultraljud. Det visade sig att ultraljudets inverkan var oberoende av sockerhalten och vätetrycket och att bestrålningen gynnade hydreringen av D-galaktos trots att den inte förhindrade Ru/C-katalysatorns deaktivering överhuvudtaget. En kinetisk modell som beaktade deaktiveringen utvecklades. Kontinuerlig hydrering av L-arabinos genomfördes med tre olika Ru-katalysatorer på tre olika bärare: tyg av aktivt kol, kolnanorör på svampliknande metalliska strukturer samt krossade partiklar av en kommersiell Ru/C-katalysator. Det visade sig att det var möjligt att omvandla L-arabinos till arabitol med höga selektiviteter med hjälp av Ru/koltyg-katalysatorn. Dessa experiment demonstrerade att hydreringen av de valda sockerarterna är en helt genomförbar rutt till framställning av fin- och specialkemikalier, som kan förverkligas i större skala.

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Emerging markets have come to play a significant role in the world, not only due to their strong economic growth but because they have been able to foster an increasing number of innovative high technology oriented firms. However, as the markets continue to change and develop, there remain many companies in emerging markets that struggle with their competitiveness and innovativeness. To improve competitive capabilities, many scholars have come to favor interfirm cooperation, which is perceived to help companies access new knowledge and complementary resources and, by so doing, enables them to catch up quickly with Western competitors. Regardless of numerous attempts by strategic management scholars, the research field remains very fragmented and lacks understanding on how and when interfirm cooperation contributes to firm performance and competiveness in emerging markets. Furthermore, the reasons why interfirm R&D sometimes succeeds but fails at other times frequently remain unidentified. This thesis combines the extant literature on competitive and cooperative strategy, dynamic capabilities, and R&D cooperation while studying interfirm R&D relationships in and between Russian manufacturing companies. Employing primary survey data, the thesis presents numerous novel findings regarding the effect of R&D cooperation and different types of R&D partner on firms’ exploration and exploitation performance. Utilizing a competitive strategy framework enables these effects to be explained in more detail, and especially why interfirm cooperation, regardless of its potential, has had a modest effect on the general competitiveness of emerging market firms. This thesis contributes especially to the strategic management literature and presents a more holistic perspective on the usefulness of cooperative strategy in emerging markets. It provides a framework through which it is possible to assess the potential impacts of different R&D cooperation partners and to clarify the causal relationships between cooperation, performance, and long term competitiveness.

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Teoksessa A complete system of geography / E. Bowen, (London) 1747. Plate n:o 25.

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Due to the intense international competition, demanding, and sophisticated customers, and diverse transforming technological change, organizations need to renew their products and services by allocating resources on research and development (R&D). Managing R&D is complex, but vital for many organizations to survive in the dynamic, turbulent environment. Thus, the increased interest among decision-makers towards finding the right performance measures for R&D is understandable. The measures or evaluation methods of R&D performance can be utilized for multiple purposes; for strategic control, for justifying the existence of R&D, for providing information and improving activities, as well as for the purposes of motivating and benchmarking. The earlier research in the field of R&D performance analysis has generally focused on either the activities and considerable factors and dimensions - e.g. strategic perspectives, purposes of measurement, levels of analysis, types of R&D or phases of R&D process - prior to the selection of R&Dperformance measures, or on proposed principles or actual implementation of theselection or design processes of R&D performance measures or measurement systems. This study aims at integrating the consideration of essential factors anddimensions of R&D performance analysis to developed selection processes of R&D measures, which have been applied in real-world organizations. The earlier models for corporate performance measurement that can be found in the literature, are to some extent adaptable also to the development of measurement systemsand selecting the measures in R&D activities. However, it is necessary to emphasize the special aspects related to the measurement of R&D performance in a way that make the development of new approaches for especially R&D performance measure selection necessary: First, the special characteristics of R&D - such as the long time lag between the inputs and outcomes, as well as the overall complexity and difficult coordination of activities - influence the R&D performance analysis problems, such as the need for more systematic, objective, balanced and multi-dimensional approaches for R&D measure selection, as well as the incompatibility of R&D measurement systems to other corporate measurement systems and vice versa. Secondly, the above-mentioned characteristics and challenges bring forth the significance of the influencing factors and dimensions that need to be recognized in order to derive the selection criteria for measures and choose the right R&D metrics, which is the most crucial step in the measurement system development process. The main purpose of this study is to support the management and control of the research and development activities of organizations by increasing the understanding of R&D performance analysis, clarifying the main factors related to the selection of R&D measures and by providing novel types of approaches and methods for systematizing the whole strategy- and business-based selection and development process of R&D indicators.The final aim of the research is to support the management in their decision making of R&D with suitable, systematically chosen measures or evaluation methods of R&D performance. Thus, the emphasis in most sub-areas of the present research has been on the promotion of the selection and development process of R&D indicators with the help of the different tools and decision support systems, i.e. the research has normative features through providing guidelines by novel types of approaches. The gathering of data and conducting case studies in metal and electronic industry companies, in the information and communications technology (ICT) sector, and in non-profit organizations helped us to formulate a comprehensive picture of the main challenges of R&D performance analysis in different organizations, which is essential, as recognition of the most importantproblem areas is a very crucial element in the constructive research approach utilized in this study. Multiple practical benefits regarding the defined problemareas could be found in the various constructed approaches presented in this dissertation: 1) the selection of R&D measures became more systematic when compared to the empirical analysis, as it was common that there were no systematic approaches utilized in the studied organizations earlier; 2) the evaluation methods or measures of R&D chosen with the help of the developed approaches can be more directly utilized in the decision-making, because of the thorough consideration of the purpose of measurement, as well as other dimensions of measurement; 3) more balance to the set of R&D measures was desired and gained throughthe holistic approaches to the selection processes; and 4) more objectivity wasgained through organizing the selection processes, as the earlier systems were considered subjective in many organizations. Scientifically, this dissertation aims to make a contribution to the present body of knowledge of R&D performance analysis by facilitating dealing with the versatility and challenges of R&D performance analysis, as well as the factors and dimensions influencing the selection of R&D performance measures, and by integrating these aspects to the developed novel types of approaches, methods and tools in the selection processes of R&D measures, applied in real-world organizations. In the whole research, facilitation of dealing with the versatility and challenges in R&D performance analysis, as well as the factors and dimensions influencing the R&D performance measure selection are strongly integrated with the constructed approaches. Thus, the research meets the above-mentioned purposes and objectives of the dissertation from the scientific as well as from the practical point of view.

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Tämä tutkielma käsittelee lisäarvon syntymistä, ylläpitämistä ja hallintaa verkostoi-tuneessa tuotekehitysympäristössä. Teemahaastattelu-menetelmää käyttäen, tavoitteena on tunnistaa ja kuvata ne prosessit, käytännöt ja toimintatavat, joissa kohdeyritys on onnistunut ja joissa lisäarvoa on syntynyt. Toinen keskeinen tavoite on löytää ongelmalliset alueet lisäarvon tuottamisessa ja analysoida, miksi nämä alueet ovat ongelmallisia. Käsitteiden arvo, arvoketju ja arvoverkosto, sekä viitekirjallisuuden esimerkkien perusteella muodostetaan teoreettinen viitekehys ja kuvataan niitä hyödyllisiä toimintatapoja ja käytäntöjä, joihin panostamalla lisäarvoa syntyy. Erityisesti informaatioteknologian alalla verkostoituminen ja arvoverkosto ovat yhä merkittävämpiä tuotekehityksen toimintatapoja, mihin horisontaalisen yhteistyön kehittyminen, globalisoituminen ja informaatioteknologian nopea kehitys on johtanut. Keskeisiä tuloksia ovat tarve yhtenäisempään, prosessinomaisempaan toimintatapaan ja liiketoimintaprosessien muokkaamiseen verkostoituneen T&K ympäristön vaatimusten mukaisesti. Myös tarve paremman näkyvyyden luomiseen sekä aktiviteettien hallintaan uudentyyppisen arvoverkoston vaatimusten mukaisesti korostui tuloksissa.

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Obesity has become the leading cause of many chronic diseases, such as type 2 diabetes and cardiovascular diseases. The prevalence of obesity is high in developed countries and it is also a major cause of the use of health services. Ectopic fat accumulation in organs may lead to metabolic disturbances, such as insulin resistance.Weight loss with very-low-energy diet is known to be safe and efficient. Weight loss improves whole body insulin sensitivity, but its effects on tissue and organ level in vivo are not well known. The aims of the studies were to investigate possible changes of weight loss in glucose and fatty acid uptake and perfusion and fat distribution at tissue and organ level using positron emission tomography and magnetic resonance imaging and spectroscopy in 34 healthy obese subjects. The results showed that whole-body insulin sensitivity increased after weight loss with very-low-energy diet and this is associated with improved skeletal muscle insulin-stimulated glucose uptake, but not with adipose tissue, liver or heart glucose uptake. Liver insulin resistance decreased after weight loss. Liver and heart free fatty acid uptakes decreased concomitantly with liver and heart triglyceride content. Adipose tissue and myocardial perfusion decreased. In conclusion, enhanced skeletal muscle glucose uptake leads to increase in whole-body insulin sensitivity when glucose uptake is preserved in other organs studied. These findings suggest that lipid accumulation found in the liver and the heart in obese subjects without co-morbidies is in part reversible by reduced free fatty acid uptake after weight loss. Reduced lipid accumulation in organs may improve metabolic disturbances, e.g. decrease liver insulin resistance. Keywords: Obesity, weight loss, very-low-energy diet, adipose tissue metabolism, liver metabolism, heart metabolism, positron emission tomography

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This MSc work was done in the project of BIOMECON financed by Tekes. The prime target of the research was, to develop methods for separation and determination of carbohydrates (sugars), sugar acids and alcohols, and some other organic acids in hydrolyzed pulp samples by capillary electrophoresis (CE) using UV detection. Aspen, spruce, and birch pulps are commonly used for production of papers in Finland. Feedstock components in pulp predominantly consist of carbohydrates, organic acids, lignin, extractives, and proteins. Here in this study, pulps have been hydrolyzed in analytical chemistry laboratories of UPM Company and Lappeenranta University in order to convert them into sugars, acids, alcohols, and organic acids. Foremost objective of this study was to quantify and identify the main and by-products in the pulp samples. For the method development and optimization, increased precision in capillary electrophoresis was accomplished by calculating calibration data of 16 analytes such as D-(-)-fructose, D(+)-xylose, D(+)-mannose, D(+)-cellobiose, D-(+)-glucose, D-(+)-raffinose, D(-)-mannitol, sorbitol, rhamnose, sucrose, xylitol, galactose, maltose, arabinose, ribose, and, α-lactose monohydratesugars and 16 organic acids such as D-glucuronic, oxalic, acetic, propionic, formic, glycolic, malonic, maleic, citric, L-glutamic, tartaric, succinic, adipic, ascorbic, galacturonic, and glyoxylic acid. In carbohydrate and polyalcohol analyses, the experiments with CE coupled to direct UV detection and positive separation polarity was performed in 36 mM disodium hydrogen phosphate electrolyte solution. For acid analyses, CE coupled indirect UV detection, using negative polarity, and electrolyte solution made of 2,3 pyridinedicarboxylic acid, Ca2+ salt, Mg2+ salts, and myristyltrimethylammonium hydroxide in water was used. Under optimized conditions, limits of detection, relative standard deviations and correlation coefficients of each compound were measured. The optimized conditions were used for the identification and quantification of carbohydrates and acids produced by hydrolyses of pulp. The concentrations of the analytes varied between 1 mg – 0.138 g in liter hydrolysate.

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Background: Atherosclerosis begins in early life progressing from asymptomatic to symptomatic as we age. Although substantial progress has been made in identifying the determinants of atherosclerosis in middle to older age adults at increased cardiovascular risk, there is lack of data examining determinants and prediction of atherosclerosis in young adults. Aims: The current study was designed to investigate levels of cardiovascular risk factors in young adults, subclinical measures of atherosclerosis, and prediction of subclinical arterial changes with conventional risk factor measures and novel metabolic profiling of serum samples. Subjects and Methods: This thesis utilised data from the follow-ups performed in 2001 and 2007 in the Cardiovascular Risk in Young Finns study, a Finnish population-based prospective cohort study that examined 2,204 subjects who were aged 30-45 years in 2007. Subclinical atherosclerosis was studied using noninvasive ultrasound measurements of carotid intima-media thickness (IMT), carotid arterial distensibility (CDist) and brachial flow-mediated dilation (FMD). Measurements included conventional risk factors and metabolic profiling using highthroughput nuclear magnetic resonance (NMR) methods that provided data on 42 lipid markers and 16 circulating metabolites. Results: Trends in lipids were favourable between 2001 and 2007, whereas waist circumference, fasting glucose, and blood pressure levels increased. To study the stability of noninvasive ultrasound markers, 6-year tracking (the likelihood to maintain the original fractile over time) in 6 years was examined. IMT tracked more strongly than CDist and FMD. Cardiovascular risk scores (Framingham, SCORE, Finrisk, Reynolds and PROCAM) predicted subclinical atherosclerosis equally. Lipoprotein subclass testing did not improve the prediction of subclinical atherosclerosis over and above conventional risk factors. However, circulating metabolites improved risk stratification. Tyrosine and docosahexaenoic acid were found to be novel biomarkers of high IMT. Conclusions: Prediction of cardiovascular risk in young Finnish adults can be performed with any of the existing risk scores. The addition of metabonomics to risk stratification improves prediction of subclinical changes and enables more accurate targeting of prevention at an early stage.

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Background: The m.3243A>G mutation in mitochondrial DNA is the most common cause for mitochondrial diabetes. In addition, unexpected deaths related to the m.3243A>G associate with encephalopathy and cardiomyopathy. Failing mitochondrial respiratory chain in neurons, myocytes and beta cells is considered to underlie the multiorgan manifestations of the m.3243A>G. Aims: The primary aim of the study was to characterize the organ-specific glucose metabolism in patients with m.3243A>G and secondly, to study patients with or without signs of diabetes, cardiomyopathy or encephalopathy. The insulin-stimulated glucose metabolism in brain, heart, skeletal muscle, adipose tissue and liver were measured with 2-deoxy-2-[18F]fluoro-α-D-glucose in 15 patients and 14 controls. Brain oxygen metabolism was assessed with [15O]oxygen and insulin secretion was modelled based on oral glucose tolerance test. Results: The glucose oxidation in brain was globally decreased in patients with or without clinical encephalopathy. The insulin-stimulated glucose influx to skeletal muscle and adipose tissue was decreased in patients with or without diabetes as the hepatic glucose metabolism was normal. Impaired beta cell function and myocardial glucose uptake were associated with the high m.3243A>G heteroplasmy. Conclusions: This cross-sectional study suggests that: 1) The ability of insulin to stimulate glucose metabolism in skeletal muscle and adipose tissue is weakened before the beta cell failure results in mitochondrial diabetes. 2) Glucose oxidation defect is detected in otherwise unaffected cerebral regions in patients with the m.3243A>G, thus it likely precedes the clinical encephalopathy. 3) Uneconomical glucose hypometabolism during hyperinsulinemia contributes to the cardiac vulnerability in patients with high m.3243A>G heteroplasmy