1,544 research outputs found

    Estimating Space-Dependent Coefficients for 1D Transport Using Gaussian Processes as State Estimator in the Frequency Domain

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    This letter presents a method to estimate the space-dependent transport coefficients (diffusion, convection, reaction, and source/sink) for a generic scalar transport model, e.g., heat or mass. As the problem is solved in the frequency domain, the complex valued state as a function of the spatial variable is estimated using Gaussian process regression. The resulting probability density function of the state, together with a semi-discretization of the model, and a linear parameterization of the coefficients are used to determine the maximum likelihood solution for these space-dependent coefficients. The proposed method is illustrated by simulations

    Trajectories of land use change in Europe: a model-based exploration of rural futures

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    Land use change is characterized by a high diversity of change trajectories depending on the local conditions, regional context and external influences. Policy intervention aims to counteract the negative consequences of these changes and provide incentives for positive developments. Region typologies are a common tool to cluster regions with similar characteristics and possibly similar policy needs. This paper provides a typology of land use change in Europe at a high spatial resolution based on a series of different scenarios of land use change for the period 2000-2030. A series of simulation models ranging from the global to the landscape level are used to translate scenario conditions in terms of demographic, economic and policy change into changes in European land use pattern. A typology developed based on these simulation results identifies the main trajectories of change across Europe: agricultural abandonment, agricultural expansion and urbanization. The results are combined with common typologies of landscape and rurality. The findings indicate that the typologies based on current landscape and ruralities are poor indicators of the land use dynamics simulated for the regions. It is advocated that typologies based on (simulated) future dynamics of land change are more appropriate to identify regions with potentially similar policy need

    Toiminimen kirjanpito

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    Opinnäytetyön tavoitteena oli selvittää mitä osaamista tarvitaan toiminimen kirjanpidon toteuttamiseen. Työn toimeksiantajana toimi tamperelainen hyvinvointialan yrittäjä, joka ei ole toiminnastaan alv-velvollinen. Työn tarkoituksena oli kouluttaa tekijä peruskirjanpidon hoitamiseen. Tarkoituksena oli, että toimeksiantajan kirjanpito sekä veroilmoituksen täyttäminen ovat vuodesta 2017 eteenpäin opinnäytetyön tekijän vastuulla. Työn teoriaosuudessa keskityttiin kirjanpidollisiin peruskäsitteisiin toimeksiantajan elinkeinotoiminnan luonne huomioiden. Verotuksen osuudessa keskityttiin yritystulon verottamiseen yleensä ja esiteltiin ammatinharjoittajan veroilmoitus siltä osin, kun se toimeksiantajan yritystoiminta huomioiden oli tarpeellista. Sen lisäksi, että tekijä perehdytti itsensä alusta alkaen kirjanpidon maailmaan, teki työstä työlään erityisesti edellisvuosien kirjanpitomateriaaliin tutustuminen, sopivan kirjanpito-ohjelman etsiminen ja juoksevan kirjanpidon suorittaminen. Opinnäyteyön tavoite toteutui, sillä työn tekijällä on nyt tarvittava osaaminen kirjanpito-ohjelman käyttämiseen sekä juoksevan kirjanpidon hoitamiseen. Kirjanpidollisiin perusasioihin keskittyminen oli työn tavoitteen toteutumisen kannalta tärkeää, sillä perustietoja kirjanpidosta tekijällä ei juurikaan ennestään ollut. Toimeksiantajan kirjanpito on tällä hetkellä toteutettuna Tappio kirjanpito-ohjelmaa käyttäen elokuun 2017 loppuun asti. Opinnäytetyön liitteenä on Tappio-ohjelmasta poimitut tuloslaskelma ja tase. Kirjaukset perustavat tapahtumiin, jotka ovat muodostuneet 31.8.2017 mennessä. Opinnäytetyötä varten lukuja on muunnettu. Työ ei suinkaan lopu raportin palauttamiseen. Juoksevaa kirjanpitoa jatketaan loppuvuoden osalta ja tilinpäätös tulee toteuttaa vuoden 2018 alussa todellisia tilikauden lukuja käyttäen. Toimeksiantaja on myös ulkoistanut veroilmoituksen täyttämisen tämän työn tekijälle. Prosessin myötä tekijän osaaminen toiminimen kirjanpidon hoitamiseen on kohonnut ammattimaiselle tasolle, joten kirjanpitopalvelua voi jatkossa tarjota myös muille toiminimiyrittäjille. Tekijä jatkaa osaamisen kartoitusta tutustumalla alv-kirjauksiin.The purpose of this thesis was to find out what skills are required to perform the accounting for a sole trader. The commissioner was a welfare entrepreneur who practices business in Tampere. The business is not liable to pay value added tax. The aim of the thesis was to give the author the capability to perform the commissioner´s accounting independently in the future. The theoretical part of the thesis focused on the basic bookkeeping concepts considering the nature of the commissioner´s business. The taxation section focused on the business income, and the tax return was presented, as it is necessary for the commissioner´s business. An essential part of the work process was to familiarize with the accounting material of the previous years, to find a suitable accounting program, and to perform the current bookkeeping. The author is now capable of using the accounting program and keeping the accounts until preparing the income statement and balance sheet. Thus the goal of the thesis was reached. The routine bookkeeping continues and the financial statements will be prepared at the end of the year. The author will also complete the tax return for the financial year of 2017. Because of the professional development, the author can provide bookkeeping services to other welfare entrepreneurs, too

    Low-power operation using self-timed circuits and adaptive scaling of the supply voltage

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    Recent research has demonstrated that for certain types of applications like sampled audio systems, self-timed circuits can achieve very low power consumption, because unused circuit parts automatically turn into a stand-by mode. Additional savings may be obtained by combining the self-timed circuits with a mechanism that adaptively adjusts the supply voltage to the smallest possible, while maintaining the performance requirements. This paper describes such a mechanism, analyzes the possible power savings, and presents a demonstrator chip that has been fabricated and tested. The idea of voltage scaling has been used previously in synchronous circuits, and the contributions of the present paper are: 1) the combination of supply scaling and self-timed circuitry which has some unique advantages, and 2) the thorough analysis of the power savings that are possible using this technique

    Laboratory-evolved Vanillyl-alcohol Oxidase Produces Natural Vanillin

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    The flavoenzyme vanillyl-alcohol oxidase was subjected to random mutagenesis to generate mutants with enhanced reactivity to creosol (2-methoxy-4-methylphenol). The vanillyl-alcohol oxidase-mediated conversion of creosol proceeds via a two-step process in which the initially formed vanillyl alcohol (4-hydroxy-3-methoxybenzyl alcohol) is oxidized to the widely used flavor compound vanillin (4-hydroxy-3-methoxybenzaldehyde). The first step of this reaction is extremely slow due to the formation of a covalent FAD N-5-creosol adduct. After a single round of error-prone PCR, seven mutants were generated with increased reactivity to creosol. The single-point mutants I238T, F454Y, E502G, and T505S showed an up to 40-fold increase in catalytic efficiency (k(cat)/K-m) with creosol compared with the wild-type enzyme. This enhanced reactivity was due to a lower stability of the covalent flavin-substrate adduct, thereby promoting vanillin formation. The catalytic efficiencies of the mutants were also enhanced for other ortho-substituted 4-methylphenols, but not for p-cresol (4-methylphenol). The replaced amino acid residues are not located within a distance of direct interaction with the substrate, and the determined three-dimensional structures of the mutant enzymes are highly similar to that of the wild-type enzyme. These results clearly show the importance of remote residues, not readily predicted by rational design, for the substrate specificity of enzymes

    Phenolic compounds and related enzymes as determinants of sorghum for food use

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    Phenolic compounds and related enzymes such as phenol biosynthesizing enzymes (phenylalanine ammonia lyase) and phenol catabolizing enzymes (polyphenol oxidase and peroxidase) are determinants for sorghum utilization as human food because they influence product properties during and after sorghum processing. Phenolic compounds are quality-grade markers for the preparation of several foods because of enzyme inhibitory activities, color, or antioxidant activities. Large inter-varietal differences in contents of phenolic compounds and their antioxidant activities among sorghum varieties exist. Moreover, some red sorghum varieties have higher antioxidant activities than the most important sources of natural antioxidants. Oxidation products of peroxidase and polyphenol oxidase (benzoquinones and polymeric compounds) affect food quality. This paper reviews the current advances in phenolic compounds and phenolic enzymes in sorghum as human food, with emphasis on nutritional and health aspects. The suitability of sorghum varieties for food and beverages is discussed

    Substrate binding tunes the reactivity of hispidin 3-hydroxylase, a flavoprotein monooxygenase involved in fungal bioluminescence

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    Fungal bioluminescence was recently shown to depend on a unique oxygen-dependent system of several enzymes. However, the identities of the enzymes did not reveal the full biochemical details of this process, as the enzymes do not bear resemblance to those of other luminescence systems, and thus the properties of the enzymes involved in this fascinating process are still unknown. Here, we describe the characterization of the penultimate enzyme in the pathway, hispidin 3-hydroxylase, from the luminescent fungus Mycena chlorophos (McH3H), which catalyzes the conversion of hispidin to 3-hydroxyhispidin. 3-Hydroxyhispidin acts as a luciferin substrate in luminescent fungi. McH3H was heterologously expressed in Escherichia coli and purified by affinity chromatography with a yield of 100 mg/liter. McH3H was found to be a single component monomeric NAD(P)H-dependent FAD-containing monooxygenase having a preference for NADPH. Through site-directed mutagenesis, based on a modeled structure, mutant enzymes were created that are more efficient with NADH. Except for identifying the residues that tune cofactor specificity, these engineered variants may also help in developing new hispidin-based bioluminescence applications. We confirmed that addition of hispidin to McH3H led to the formation of 3-hydroxyhispidin as sole aromatic product. Rapid kinetic analysis revealed that reduction of the flavin cofactor by NADPH is boosted by hispidin binding by nearly 100-fold. Similar to other class A flavoprotein hydroxylases, McH3H did not form a stable hydroperoxyflavin intermediate. These data suggest a mechanism by which the hydroxylase is tuned for converting hispidin into the fungal luciferin.</p

    Sorghum grain as human food in Africa: relevance of content of starch and amylase activities

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    Sorghum is a staple food grain in many semi-arid and tropic areas of the world, notably in Sub-Saharan Africa because of its good adaptation to hard environments and its good yield of production. Among important biochemical components for sorghum processing are levels of starch (amylose and amylopectin) and starch depolymerizing enzymes. Current research focus on identifying varieties meeting specific agricultural and food requirements from the great biodiversity of sorghums to insure food security. Results show that some sorghums are rich sources of micronutrients (minerals and vitamins) and macronutrients (carbohydrates, proteins and fat). Sorghum has a resistant starch, which makes it interesting for obese and diabetic people. In addition, sorghum may be an alternative food for people who are allergic to gluten. Malts of some sorghum varieties display a-amylase and ß-amylase activities comparable to those of barley, making them useful for various agro-industrial foods. The feature of sorghum as a food in developing as well as in developed countries is discussed. A particular emphasis is made on the impact of starch and starch degrading enzymes in the use of sorghum for some African foods, e.g. “tô”, thin porridges for infants, granulated foods “couscous”, local beer “dolo”, as well agro-industrial foods such as lager beer and bread.Keywords: sorghum, a-amylase, b-amylase, starch, infant porridge, beer, couscous, dolo, tô, brea

    Prefilled Cyclic Olefin Sterilized Syringes of Norepinephrine Injection Solution Do Not Need to Be Stabilized by Antioxidants

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    Norepinephrine is a potent α-sympathomimetic drug which plays an important role in the acute treatment of hypotension and shock. Commercially available norepinephrine solutions contain sodium metabisulfite (Na2S2O5) as an antioxidant. However, prefilled cyclic olefin polymer syringes are not compatible with sodium metabisulfite. The aim of this study was to develop a new formulation of 0.1-mg/mL norepinephrine solution without sodium metabisulfite which is chemically stable and sterile and can be stored in prefilled polymer syringes. Formulation studies were performed with 0.1-mg/mL norepinephrine solution with 0, 0.05, or 0.1% ascorbic acid added as antioxidant. The syringes were filled under nitrogen gassing, stored at 20 ± 5°C, and protected from daylight. Based on the formulation test results, the final formulation was defined and stability testing at 20 ± 5°C was performed measuring norepinephrine concentration, pH, clarity, color of the solution, subvisible particles, and sterility at time intervals up to 12 months. The norepinephrine concentrations at t = 22 weeks were 100.4%, 95.4%, and 92.2% for the formulations with no ascorbic acid and with 0.05% and 0.10% ascorbic acid, respectively. Three batches for the stability study were produced containing norepinephrine, sodium edetate, sodium chloride, and water for injections filled under nitrogen gassing and stored at 20 ± 5°C. Norepinephrine concentrations were respectively 98.8%, 98.6%, and 99.3% for batches 1, 2, and 3 at t = 12 months. It can be concluded that norepinephrine (0.1 mg/mL) solution without metabisulfite is stable for at least 12 months at room temperature when protected from daylight
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