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Datagedreven businessmodellen ontwikkelen

Thauera aminoaromatica MZ1T Identified as a Polyhydroxyalkanoate-Producing Bacterium within a Mixed Microbial Consortium

Polyhydroxyalkanoates (PHAs) form a highly promising class of bioplastics for the transition from fossil fuel-based plastics to bio-renewable and biodegradable plastics. Mixed microbial consortia (MMC) are known to be able to produce PHAs from organic waste streams. Knowledge of key-microbes and their characteristics in PHA-producing consortia is necessary for further process optimization and direction towards synthesis of specific types of PHAs. In this study, a PHA-producing mixed microbial consortium (MMC) from an industrial pilot plant was characterized and further enriched on acetate in a laboratory-scale selector with a working volume of 5 L. 16S-rDNA microbiological population analysis of both the industrial pilot plant and the 5 L selector revealed that the most dominant species within the population is Thauera aminoaromatica MZ1T, a Gram-negative beta-proteobacterium belonging to the order of the Rhodocyclales. The relative abundance of this Thauera species increased from 24 to 40% after two months of enrichment in the selector-system, indicating a competitive advantage, possibly due to the storage of a reserve material such as PHA. First experiments with T. aminoaromatica MZ1T showed multiple intracellular granules when grown in pure culture on a growth medium with a C:N ratio of 10:1 and acetate as a carbon source. Nuclear magnetic resonance (NMR) analyses upon extraction of PHA from the pure culture confirmed polyhydroxybutyrate production by T. aminoaromatica MZ1T.

Application of Caenorhabditis elegans (nematode) and Danio rerio embryo (zebrafish) as model systems to screen for developmental and reproductive toxicity of Piperazine compounds

From the article: "To enable selection of novel chemicals for new processes, there is a recognized need for alternative toxicity screening assays to assess potential risks to man and the environment. For human health hazard assessment these screening assays need to be translational to humans, have high throughput capability, and from an animal welfare perspective be harmonized with the principles of the 3Rs (Reduction, Refinement, Replacement). In the area of toxicology a number of cell culture systems are available but while these have some predictive value, they are not ideally suited for the prediction of developmental and reproductive toxicology (DART). This is because they often lack biotransformation capacity, multicellular or multi- organ complexity, for example, the hypothalamus pituitary gonad (HPG) axis and the complete life cycle of whole organisms. To try to overcome some of these limitations in this study, we have used Caenorhabditis elegans (nematode) and Danio rerio embryos (zebrafish) as alternative assays for DART hazard assessment of some candidate chemicals being considered for a new commercial application. Nematodes exposed to Piperazine and one of the analogs tested showed a slight delay in development compared to untreated animals but only at high concentrations and with Piperazine as the most sensitive compound. Total brood size of the nematodes was also reduced primarily by Piperazine and one of the analogs. In zebrafish Piperazine and analogs showed developmental delays. Malformations and mortality in individual fish were also scored. Significant malformations were most sensitively identified with Piperazine, significant mortality was only observed in Piperazine and only at the higest dose. Thus, Piperazine seemed the most toxic compound for both nematodes and zebrafish. The results of the nematode and zebrafish studies were in alignment with data obtained from conventional mammalian toxicity studies indicating that these have potential as developmental toxicity screening systems. The results of these studies also provided reassurance that none of the Piperazines tested are likely to have any significant developmental and/or reproductive toxicity issues to humans when used in their commercial applications."

Gids voor onderzoeksvisitaties volgens het BKO

Praktijkgericht onderzoek aan hogescholen kent een grote diversiteit aan onderwerpen, aanpakken en uitvoering. Het Brancheprotocol Kwaliteitszorg Onderzoek (BKO) heeft tot doel om een gezamenlijk gesprek te kunnen voeren over de ontwikkeling van praktijkgericht onderzoek. Hiertoe reikt het protocol een beoordelingskader aan met vier thema’s: profiel, impact, organisatie en kwaliteit. Het gesprek is gericht op de verdere ontwikkeling van het onderzoek, zowel van individuele onderzoekseenheden als van praktijkgericht onderzoek als landelijk geheel. Een aantal samenhangende essentiële kenmerken van het kader, die daarmee de basis vormen voor het gesprek en de uiteindelijke beoordeling, zijn:‒ Ontwikkelingsgericht: hierbij gaat het om het continue proces van veranderingen in het praktijkgericht onderzoek te plaatsen in historisch perspectief en het gebruiken van een waarderende benadering die gebruik maakt van wat goed gaat en niet verder gaat met wat niet blijkt te werken.‒ Formatief: hierbij gaat het om reflectief handelen op het continue proces van veranderingen, ter lering en verbetering.‒ Contextueel: hierbij gaat het om het laten doorklinken en tot zijn recht laten komen van de context waarin het praktijkgericht onderzoek plaatsvindt.‒ Praktijkgericht: hierbij gaat het om vraagstellingen die komen vanuit de beroepspraktijk.In het BKO is aan het Landelijk Netwerk Kwaliteitszorg Onderzoek (LNKO) twee opdrachten gegeven, namelijk: het opstellen van een handreiking voor een zelfevaluatie én het opstellen van een handreiking voor een visitatierapport. Binnen een werkgroep van het LNKO zijn deze opdrachten opgepakt en uitgewerkt in dit document. Daarbij is de handreiking voor het visitatierapport opgesteld in samenspraak met de CEKO.Het doel van deze gids is om degenen die betrokken zijn bij het visitatietraject concrete tips en adviezen te geven voor de verschillende onderdelen in dit traject. Deze tips en adviezen zijn verzameld op basis van de ervaringen en evaluaties van vele voorgaande onderzoeksvisitaties in diverse instellingen. Voor het format van de zelfevaluatie gaat het om suggesties en is er een grote mate van vormvrijheid. Wat het format van het visitatierapport betreft, heeft de CEKO een sterke voorkeur voor het gebruik ervan.Hoofdstuk 2 geeft een korte toelichting op het huidige BKO en beschrijft de belangrijkste wijzigingen ten opzichte van de voorgaande versie. Het BKO is de basis voor de visitaties en wordt verondersteld bekend te zijn. Deze handreiking geeft, in aanvulling op het BKO, handvatten voor het werken met het protocol.In hoofdstuk 3 worden de stappen in het visitatieproces weergegeven en staan enkele aandachtspunten voor de voorbereiding op de visitatie. Dit hoofdstuk belicht ook de rollen en verantwoordelijkheden van de betrokkenen voor het hele visitatietraject, te weten CvB, de onderzoekseenheid en kwaliteitszorgmedewerker en/of -adviseur.De aandachtspunten voor de samenstelling van het visitatiepanel worden in hoofdstuk 4 toegelicht.De laatste drie hoofdstukken geven adviezen en richtlijnen voor de drie documenten die als onderdeel van het visitatietraject worden geschreven, respectievelijk voor de zelfevaluatie in hoofdstuk 5, het visitatierapport in hoofdstuk 6 en de bestuurlijke reactie in hoofdstuk 7.

New approach methodologies (NAMs) for human-relevant biokinetics predictions

For almost fifteen years, the availability and regulatory acceptance of new approach methodologies (NAMs) to assess the absorption, distribution, metabolism and excretion (ADME/biokinetics) in chemical risk evaluations are a bottleneck. To enhance the field, a team of 24 experts from science, industry, and regulatory bodies, including new generation toxicologists, met at the Lorentz Centre in Leiden, The Netherlands. A range of possibilities for the use of NAMs for biokinetics in risk evaluations were formulated (for example to define species differences and human variation or to perform quantitative in vitro-in vivo extrapolations). To increase the regulatory use and acceptance of NAMs for biokinetics for these ADME considerations within risk evaluations, the development of test guidelines (protocols) and of overarching guidance documents is considered a critical step. To this end, a need for an expert group on biokinetics within the Organisation of Economic Cooperation and Development (OECD) to supervise this process was formulated. The workshop discussions revealed that method development is still required, particularly to adequately capture transporter mediated processes as well as to obtain cell models that reflect the physiology and kinetic characteristics of relevant organs. Developments in the fields of stem cells, organoids and organ-on-a-chip models provide promising tools to meet these research needs in the future.

Surface and Bulk Modification of Synthetic Textiles to Improve Dyeability

Synthetic fibers, mainly polyethylene terephthalate (PET), polyamide (PA), polyacrylonitrile (PAN) and polypropylene (PP), are the most widely used polymers in the textile industry. These fibers surpass the production of natural fibers with a market share of 54.4%. The advantages of these fibers are their high modulus and strength, stiffness, stretch or elasticity, wrinkle and abrasion resistances, relatively low cost, convenient processing, tailorable performance and easy recycling. The downside to synthetic fibers use are reduced wearing comfort, build-up of electrostatic charge, the tendency to pill, difficulties in finishing, poor soil release properties and low dyeability. These disadvantages are largely associated with their hydrophobic nature. To render their surfaces hydrophilic, various physical, chemical and bulk modification methods are employed to mimic the advantageous properties of their natural counterparts. This review is focused on the application of recent methods for the modification of synthetic textiles using physical methods (corona discharge, plasma, laser, electron beam and neutron irradiations), chemical methods (ozone-gas treatment, supercritical carbon dioxide technique, vapor deposition, surface grafting, enzymatic modification, sol-gel technique, layer-by-layer deposition of nano-materials, micro-encapsulation method and treatment with different reagents) and bulk modification methods by blending polymers with different compounds in extrusion to absorb different colorants. Nowadays, the bulk and surface functionalization of synthetic fibers for various applications is considered as one of the best methods for modern textile finishing processes (Tomasino, 1992). This last stage of textile processing has employed new routes to demonstrate the great potential of nano-science and technology for this industry (Lewin, 2007). Combination of physical technologies and nano-science enhances the durability of textile materials against washing, ultraviolet radiation, friction, abrasion, tension and fading (Kirk–Othmer, 1998). European methods for application of new functional finishing materials must meet high ethical demands for environmental-friendly processing (Fourne, 1999). For this purpose the process of textile finishing is optimized by different researchers in new findings (Elices & Llorca, 2002). Application of inorganic and organic nano-particles have enhanced synthetic fibers attributes, such as softness, durability, breathability, water repellency, fire retardancy and antimicrobial properties (Franz, 2003; McIntyre, 2005; Xanthos, 2005). This review article gives an application overview of various physical and chemical methods of inorganic and organic structured material as potential modifying agents of textiles with emphasis on dyeability enhancements. The composition of synthetic fibers includes polypropylene (PP), polyethylene terephthalate (PET), polyamides (PA) or polyacrylonitrile (PAN). Synthetic fibers already hold a 54% market share in the fiber market. Of this market share, PET alone accounts for almost 50% of all fiber materials in 2008 (Gubitz & Cavaco-Paulo, 2008). Polypropylene, a major component for the nonwovens market accounts for 10% of the market share of both natural and synthetic fibers worldwide (INDA, 2008 and Aizenshtein, 2008). It is apparent that synthetic polymers have unique properties, such as high uniformity, mechanical strength and resistance to chemicals or abrasion. However, high hydrophobicity, the build-up of static charges, poor breathability, and resistant to finishing are undesirable properties of synthetic materials (Gubitz & Cavaco-Paulo, 2008). Synthetic textile fibers typically undergo a variety of pre-treatments before dyeing and printing is feasible. Compared to their cotton counterparts, fabrics made from synthetic fibers undergo mild scouring before dyeing. Nonetheless, these treatments still create undesirable process conditions wh