983 research outputs found

    Distribution and Abundance of the Polychaete, Manayunkia Speciosa Leidy, in Western Lake Erie

    Get PDF
    Author Institution: U. S. Bureau of Commercial Fisheries, Biological Laboratory, Ann Arbor, MichiganThe abundance and distribution of the freshwater polychaete, Manayunkia speciosa, in 1961, are described for western Lake Erie. Previous records reveal that the species has either been generally overlooked or presently its numbers have greatly increased in the area considered

    Mini-Intein Structures from Extremophiles Suggest a Strategy for Finding Novel Robust Inteins

    Get PDF
    Inteins are prevalent among extremophiles. Mini-inteins with robust splicing properties are of particular interest for biotechnological applications due to their small size. However, biochemical and structural characterization has still been limited to a small number of inteins, and only a few serve as widely used tools in protein engineering. We determined the crystal structure of a naturally occurring Pol-II mini-intein from Pyrococcus horikoshii and compared all three mini-inteins found in the genome of P. horikoshii. Despite their similar sizes, the comparison revealed distinct differences in the insertions and deletions, implying specific evolutionary pathways from distinct ancestral origins. Our studies suggest that sporadically distributed mini-inteins might be more promising for further protein engineering applications than highly conserved mini-inteins. Structural investigations of additional inteins could guide the shortest path to finding novel robust mini-inteins suitable for various protein engineering purposes

    Antioxidant studies for animal-based fat methyl ester

    Get PDF
    The aim of this study was to test an antioxidant, BioSineox, for animal-based fat methyl ester, AFME, in order to determine the optimal concentration of this antioxidant for meeting the six-hour oxidation stability requirement as set in the EN 14214:2010 standard. Oxidation stability was measured using a Biodiesel Rancimat 873, which meets the requirements of the EN 14112 standard. The variety of raw materials used in the production of methyl esters, i.e. biodiesels, renders a variety of fatty acid profiles. Consequently, the reaction of biodiesels with various antioxidants must be individually tested for each combination. Before the antioxidant is added during the manufacturing process, it must be tested in laboratory conditions. As the main result of this study it can be stated that the process requires a relatively high (2,000 ppm) BioSineox concentration in order for the biodiesel to meet the six-hour oxidation stability requirement. In March 2013, the standard EN 14214:2010 was replaced by the EN 14214:2012. One of the changes was an increase in the oxidation stability requirement from 6 hours minimum to 8 hours minimum. To reach this target, the concentration of the antioxidant must be further increased.© 2014 The Authors. This is an open access journal distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence https://creativecommons.org/licenses/by-nc-nd/4.0/fi=vertaisarvioitu|en=peerReviewed

    Mini-Intein Structures from Extremophiles Suggest a Strategy for Finding Novel Robust Inteins

    Get PDF
    Inteins are prevalent among extremophiles. Mini-inteins with robust splicing properties are of particular interest for biotechnological applications due to their small size. However, biochemical and structural characterization has still been limited to a small number of inteins, and only a few serve as widely used tools in protein engineering. We determined the crystal structure of a naturally occurring Pol-II mini-intein from Pyrococcus horikoshii and compared all three mini-inteins found in the genome of P. horikoshii. Despite their similar sizes, the comparison revealed distinct differences in the insertions and deletions, implying specific evolutionary pathways from distinct ancestral origins. Our studies suggest that sporadically distributed mini-inteins might be more promising for further protein engineering applications than highly conserved mini-inteins. Structural investigations of additional inteins could guide the shortest path to finding novel robust mini-inteins suitable for various protein engineering purposes

    Palveleva johtaminen etätyössä

    Get PDF
    Tiivistelmä. Tämän kandidaatintutkielman tarkoituksena on perehtyä palvelevan johtamisen vaikutuksiin etätyössä. Tutkimus käsittelee palvelevaa johtamista sekä etätyön johtamista yksittäisinä käsitteinä, sekä tutkii kuinka ne ovat suhteessa toisiinsa. Tutkielman tavoitteena on selvittää onko palveleva johtaminen etätyön johtamiseen soveltuva johtamistyyli

    Structural studies on Δ3-Δ2-enoyl-CoA isomerase: the variable mode of assembly of the trimeric disks of the crotonase superfamily

    Get PDF
    AbstractSubunits of the enzymes in the crotonase superfamily form tight trimeric disks. In most members of this protein superfamily these disks assemble further into hexamers. Here we report on the 2.1 Å structure of a tight hexameric crystal form of the yeast peroxisomal Δ3-Δ2-enoyl-CoA isomerase (Eci1p). A comparison of this structure to a previously solved crystal form of Eci1p and other structures of this superfamily shows that there is much variability with respect to the relative distance between the disks and their relative orientations. In particular helices H2 and H9 are involved in the inter-trimer contacts and there are considerable structural differences in these helices in this superfamily. Helices H2 and H9 are near the catalytic cavity and it is postulated that the observed structural variability of these helices, stabilized by the different modes of assembly, has allowed the evolution of the wide range of substrate and catalytic specificity within this enzyme superfamily

    Analysis of ground heat exchanger for a ground source heat pump : A study of an existing system to find optimal borehole length to enhance the coefficient of performance

    Get PDF
    Ground Source Heat Hump is one of the emerging technic to utilize the reservoir of geothermal energy in Europe. The crucial factor is to find the optimal length of the borehole to successfully design a heating system. The length of the borehole varies depending on the geographical area, the capacity of the heat pump and heat load of the desired building in consideration. Several methods have been theorized and validated using the experimental measurements to find the optimal length of the borehole. The most commonly used methods are American Society of Heating, Refrigeration and Air-conditioning Engineers and International Ground Source Heat Pump Association for sizing borehole heat exchanger. In this paper, an existing system is analyzed, for a 60 kilo Watts heat pump in an area of Finland with a ground source 250 meters of Borehole Heat Exchanger. Coefficient of Performance for current scenario is calculated, an optimal length is found for the heat capacity of the heat pump to enhance the performance of the system. Improved coefficient of performance is presented along with an easy method of finding the optimal length of the ground source.fi=vertaisarvioitu|en=peerReviewed

    Properties of local produced animal-fat based biodiesel and its blend with fossil fuel

    Get PDF
    In the near future, more emphasis must be put on reducing greenhouse gas (GHG) emissions in road transportation, house heating, agricultural activities, marine transport etc. This study concentrated on the use of alternative fuels in engine - driven applicat ions of non - road machineries and decentralized energy production . Today, the engines are mainly designed for crude oil derived fuels and liquid renewable fuels are blended with crude oil based fuels to fulfill the requirements of renewable energy usage. Du e to the environmental reasons on one hand and to the agricultural needs, on the other hand , different blends of bio - and fossil fuels are becoming more popular. In Europe, the maximum FAME content in diesel fuel is 7 vol% according to the EN 590:2013 but higher percentages are also available and targeted around the world. For example in the United States, the 20% blend fraction is becoming more common. For these reasons, B20 fuels were chosen to be investigated in this study. Special emphasis was put on im proving blending issues since fuel blending may cause some operating risks. The main aim was to research widely the properties of animal - fat based methyl ester (AFME) and B20 fuel blend produced from it. AFME is a waste based fuel and produced in Ostroboth nia region, Finland. The aim was to find out in which engine applications the fuels are feasible and investigate if the fuels fit in the quality of automotive fuel Standards. According to the results, AFME is a feasible option to increase self - sufficient e ne rgy production in Ostrobothnia.fi=vertaisarvioitu|en=peerReviewed
    corecore