Long-standing experimental data on the elastic modulus of end-linked poly(dimethylsiloxane) (PDMS) networks are employed to corroborate the validity of the Miller-Macosko theory (MMT). The validity of MMT is also confirmed by molecular dynamics (MD) simulations that mimic the experimentally realized networks. It becomes apparent that for a network formed from bulk, where the fractions of the loops are small, it is sufficient to account for the topological details of a reference tree-like network, i.
View Article and Find Full Text PDFFilamentous enzymes have been found in all domains of life, but the advantage of filamentation is often elusive. Some anaerobic, autotrophic bacteria have an unusual filamentous enzyme for CO fixation-hydrogen-dependent CO reductase (HDCR)-which directly converts H and CO into formic acid. HDCR reduces CO with a higher activity than any other known biological or chemical catalyst, and it has therefore gained considerable interest in two areas of global relevance: hydrogen storage and combating climate change by capturing atmospheric CO.
View Article and Find Full Text PDFBiotechnol Biofuels Bioprod
May 2022
Background: In times of global warming there is an urgent need to replace fossil fuel-based energy vectors by less carbon dioxide (CO)-emitting alternatives. One attractive option is the use of molecular hydrogen (H) since its combustion emits water (HO) and not CO. Therefore, H is regarded as a non-polluting fuel.
View Article and Find Full Text PDFIn times of global climate change and the fear of dwindling resources, we are facing different considerable challenges such as the replacement of fossil fuel-based energy carriers with the coincident maintenance of the increasing energy supply of our growing world population. Therefore, CO capturing and H storing solutions are urgently needed. In this study, we demonstrate the production of a functional and biotechnological interesting enzyme complex from acetogenic bacteria, the hydrogen-dependent CO reductase (HDCR), in the well-known model organism Escherichia coli.
View Article and Find Full Text PDFAcetogenic bacteria have gained much attraction in recent years as they can produce different biofuels and biochemicals from H plus CO or even CO alone, therefore opening a promising alternative route for the production of biofuels from renewable sources compared to existing sugar-based routes. However, CO metabolism still raises questions concerning the biochemistry and bioenergetics in many acetogens. In this study, we focused on the two acetogenic bacteria Acetobacterium woodii and Thermoanaerobacter kivui which, so far, are the only identified acetogens harbouring a H -dependent CO reductase and furthermore belong to different classes of 'Rnf'- and 'Ech-acetogens'.
View Article and Find Full Text PDFBiotechnol Biofuels
February 2020
Background: In times of global climate change, the conversion and capturing of inorganic CO have gained increased attention because of its great potential as sustainable feedstock in the production of biofuels and biochemicals. CO is not only the substrate for the production of value-added chemicals in CO-based bioprocesses, it can also be directly hydrated to formic acid, a so-called liquid organic hydrogen carrier (LOHC), by chemical and biological catalysts. Recently, a new group of enzymes were discovered in the two acetogenic bacteria and which catalyze the direct hydrogenation of CO to formic acid with exceptional high rates, the hydrogen-dependent CO reductases (HDCRs).
View Article and Find Full Text PDFBiotechnol Biofuels
September 2018
Background: Replacing fossil fuels as energy carrier requires alternatives that combine sustainable production, high volumetric energy density, easy and fast refueling for mobile applications, and preferably low risk of hazard. Molecular hydrogen (H) has been considered as promising alternative; however, practical application is struggling because of the low volumetric energy density and the explosion hazard when stored in large amounts. One way to overcome these limitations is the transient conversion of H into other chemicals with increased volumetric energy density and lower risk hazard, for example so-called liquid organic hydrogen carriers such as formic acid/formate that is obtained by hydrogenation of CO.
View Article and Find Full Text PDFIntroduction: E-health has been a recurrent topic in health reform, yet its implementation, ultimate role and feasibility are yet to be clearly defined. Organisations such as the Royal Flying Doctor Service South East Section (RFDS SE) are in a position to utilise technology to enhance the effectiveness of existing clinical services for remote communities. The study aim was to explore the readiness of the remote population of far-west New South Wales, Australia, and RFDS SE as a monopoly service provider to take up e-health innovations.
View Article and Find Full Text PDFAust N Z J Public Health
June 2014
Background: Treatment decisions in colorectal cancer subsequent to surgery are based mainly on the TNM system. There is a need to establish novel prognostic markers based on the molecular characterization of tumor cells. Evidence exists that sialyl Le(X) expression is correlated with an unfavorable outcome in colorectal cancer.
View Article and Find Full Text PDFThe use of radiotherapy for plantar fasciitis has never been reported in Australasia and is scarcely found in the English language medical literature, but it is commonly used in Europe, especially in Germany. In Europe, treatment courses consisting of multiple small fractions have been associated with high levels of pain relief. In the present report, the use of single fractions or radiotherapy was evaluated by reviewing seven consecutive patients referred for treatment and by applying objective and subjective criteria for pain relief.
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