Sökning: "biological degradation"

Visar resultat 6 - 10 av 509 avhandlingar innehållade orden biological degradation.

  1. 6. Bacterial Degradation and Use of Chitin in Aquatic Habitats

    Författare :Sara Beier; Stefan Bertilsson; Ian Head; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chitin; organic matter degradation; microbial ecology; functional guild; Biology; Biologi;

    Sammanfattning : Chitin belongs to the most abundant biopolymers on earth where it has an important role as a structural element in crustaceans, insects, fungi and some phytoplankton. Missing evidence for long-term accumulation of chitin in nature implies fast turnover and as chitin is composed of aminosugar subunits it holds central roles in both carbon and nitrogen cycles. LÄS MER

  2. 7. Physiology of Saccharomyces cerevisiae Producing Recombinant Insulin in Continuous Culture

    Författare :Ali Kazemi Seresht; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; unfolded protein response; Keywords: heterologous protein production; prolonged chemostat; transcriptome; insulin analogue precursor; metabolic adaptation; URA3d; plasmid copy number; promoter truncation; high cell density cultivation; TPI1;

    Sammanfattning : The yeast Saccharomyces cerevisiae has widely been used as a host for the production of heterologous proteins. High-level production of heterologous proteins is likely to impose a metabolic burden on the host cell and can thus affect various aspects of cellular physiology. LÄS MER

  3. 8. Molecular mechanisms involved in prokaryotic cycling of labile dissolved organic matter in the sea

    Författare :Benjamin Pontiller; Jarone Pinhassi; Daniel Lundin; Catherine Legrand; Martin F. Polz; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bacteria and archaea; labile dissolved organic matter; metatranscriptomics; monomers; polymers; carbohydrate-active enzymes CAZymes ; peptidases; membrane transporters; Natural Science; Naturvetenskap; Akvatisk ekologi; Aquatic Ecology; Mikrobiologi; Microbiology;

    Sammanfattning : Roughly half of the global primary production originates from microscopic phytoplankton in marine ecosystems, converting carbon dioxide into organic matter. This organic matter pool consists of a myriad of compounds that fuel heterotrophic bacterioplankton. LÄS MER

  4. 9. Tuning the polylactide hydrolysis rate without introducing new migrants

    Författare :Sofia Regnell Andersson; Minna Hakkarainen; Karin Jacobson; Ulrika Edlund; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; polylactide; sterocomplex; plasticizer; degradation; degradation products; ESI-MS; Biochemistry; Biokemi; Polymer chemistry; Polymerkemi;

    Sammanfattning : The possibility to control and tune the hydrolytic degradation rate of polylactide without introducing any new degradation products was investigated by subjecting polylactide with cyclic or linear oligolactic acid additives, and a stereocomplex between the L- and D-enantiomers of polylactide to hydrolytic degradation at 37 and 60 °C for up to 39 weeks. The degradation was monitored by measuring mass loss, molar mass changes, water uptake, changes of surface structure, crystallinity and thermal properties. LÄS MER

  5. 10. Habitat structure, degradation and management effects on coral reef fish communities

    Författare :Saleh A.S. Yahya; Martin Gullström; Sören Nylin; Narriman Jiddawi; Yunus Mgaya; Gunilla Rosenqvist; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; fish assemblages; climate change; coral degradation; Indian Ocean; patch reefs; coral bleaching; resilience; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Coral reefs are among the most diverse and productive ecosystems on earth, and are critical to the survival of tropical marine ecosystems and sustenance of local human populations. However, coral reefs are quite vulnerable to disturbances, both natural and anthropogenic. LÄS MER