Publications by authors named "Tina G Williams"

Six urease-negative strains were isolated from cattle faeces over a 19-month period from 2009 to 2010. These strains were initially identified as by 16S rRNA gene and typing. Initial studies characterizing these strains by multilocus sequence typing and genome sequencing further supported their classification as but indicated that these strains form a divergent clade within the species.

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Article Synopsis
  • Nine strains of bacteria were isolated from cattle and feral swine feces, with some originating from a 2007 dairy outbreak and others from a 2009-2010 survey in Central California.
  • Although the species couldn't be identified using standard gene sequencing, further analyses revealed that they form a distinct novel clade related to other known bacteria, indicating that these strains are a new species.
  • These bacteria are microaerobic, motile, Gram-negative, and have unique phenotypic characteristics that differentiate them from similar species, leading to the proposed name for this new species.
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In a previous study characterizing strains deficient in selenium metabolism, 50 strains were found to be similar to, but distinct from, the selenonegative species . Initial characterization based on multilocus sequence typing and the phylogeny of a set of 20 core genes determined that these strains form three putative taxa within the selenonegative cluster. A polyphasic study was undertaken here to further clarify their taxonomic position within the genus.

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Multivariate models were developed to classify cellulose nanofibril (CNF) fibrillation by a quality index from near infrared (NIR) spectra. Commercial pulps of Eucalyptus spp. were used to produce cellulose nanofibrils by means of a fibrillator mill.

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This paper provides proof of concept that activated carbon (AC) may be readily produced using limited conversion methods and resources from sawdust of massaranduba () wood, thereby obtaining value-added products. Sawdust was sieved and heat-treated in an oxygen-free muffle furnace at 500 °C to produce charcoal. The charcoal was activated in a tubular electric furnace at 850 °C while being purged with CO gas.

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  • The study aimed to create bio-based thin films using cellulose and chitosan, and assess the effects of adding magnetite and glycerol on their properties.
  • The films displayed a good distribution of materials and showed improved flexibility and wettability, while maintaining thermal stability up to 150°C; glycerol enhanced these attributes but reduced barrier properties.
  • With the inclusion of magnetite and glycerol, the dielectric constant of the films significantly increased, indicating potential for use as eco-friendly insulators in capacitors, contributing to the reduction of e-waste.
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Due to a large and growing collection of genomic and experimental resources, Brachypodium distachyon has emerged as a powerful experimental model for the grasses. To add to these resources we sequenced 21 165 T-DNA lines, 15 569 of which were produced in this study. This increased the number of unique insertion sites in the T-DNA collection by 21 078, bringing the overall total to 26 112.

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A hybrid catalyst was prepared using cellulose nanofibrils and magnetite to degrade organic compounds. Cellulose nanofibrils were isolated by mechanical defibrillation producing a suspension used as a matrix for magnetite particles. The solution of nanofibrils and magnetite was dried and milled resulting in a catalyst with a 1:1 ratio of cellulose and magnetite that was chemically and physically characterized using light, scanning electron and transmission electron microscopies, specific surface area analysis, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, catalytic potential and degradation kinetics.

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Zein fibers were successfully fabricated via solution blow spinning (SBS) using acetic acid as solvent. Surface tension, viscosity and modulus of zein solutions were respectively determined by force tensiometer and rheometer. Increases of these properties were observed with an increase of concentration from 20% to 35% (w/w).

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The present study reports on the development of hybrid poly(lactic acid) (PLA) fibres loaded with highly crystalline bacterial cellulose nanowhiskers (BCNW) by the novel solution blow spinning method. Furthermore, fibres with antimicrobial properties were generated by incorporating carvacrol and THC as antimicrobial agents and the biocide effect against Listeria monocytogenes was studied. Initially, PLA blow spun fibres containing BCNW were optimized in terms of morphology and thermal properties.

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Unlabelled: Thyme essential oil (TEO) and apple skin polyphenols (ASP) are natural compounds considered as generally recognized as safe by FDA, with biological effects against bacteria and fungi. This work aimed to evaluate physical and antimicrobial properties of açaí edible films formulated with TEO and ASP at 3% and 6% (w/w) individually or combined at 3% (w/w) each. Physical properties studied include mechanical resistance, water vapor permeability (WVP), color, and thermal resistance.

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  • This study explored the controlled-release potential of 2-heptanone, a promising natural pesticide, when incorporated into different lipid formulations.
  • The release rate of 2-heptanone varied significantly over time, being faster in the first week and slowing down afterward, with paraffin lipid films showing the best retention.
  • The compatibility of solid lipid particles (SLPs) with the film matrix influenced release rates, as they increased release in paraffin films but decreased it in Acetem films by making the latter more firm.
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During rice milling, the bran and germ are successively removed from the caryopsis (kernel). Because bran and germ contain large quantities of lipid, the amount of lipid remaining on the kernel surface may be used as a method for the assessment of milling quality. Bulk samples of rice pureline varieties and an experimental hybrid were milled for 0, 10, 20, 30, and 40 s.

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Catastrophic phase inversion (CPI) was used as a low-energy emulsification method to prepare oil-in-water (O/W) nanoemulsions in a lipid (Acetem)/water/nonionic surfactant (Tween 60) system. CPIs in which water-in-oil emulsions (W/O) are transformed into oil-in-water emulsions (O/W) were induced by changes in the phase ratio. Dynamic phase inversion emulsification was achieved by slowly increasing the water volume fraction (fw) to obtain O/W emulsions from water in oil emulsions.

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It has been stated that hydroxypropyl methyl cellulose (HPMC) based films have promising applications in the food industry because of their environmental appeal, low cost, flexibility and transparency. Nevertheless, their mechanical and moisture barrier properties should be improved. The aim of this work was to enhance these properties by reinforcing the films with microcrystalline cellulose (MCC) at the nano scale level.

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Cellulose nanoreinforcements have been used to improve mechanical and barrier properties of biopolymers, whose performance is usually poor when compared to those of synthetic polymers. Nanocomposite edible films have been developed by adding cellulose nanofibers (CNF) in different concentrations (up to 36 g/100 g) as nanoreinforcement to mango puree based edible films. The effect of CNF was studied in terms of tensile properties, water vapor permeability, and glass transition temperature (T(g)) of the nanocomposite films.

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Coir fibers received three treatments, namely washing with water, alkali treatment (mercerization) and bleaching. Treated fibers were incorporated in starch/ethylene vinyl alcohol copolymers (EVOH) blends. Mechanical and thermal properties of starch/EVOH/coir biocomposites were evaluated.

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Xylan is the major component of hemicellulose, and xylan should be fully utilized to improve the efficiencies of a biobased economy. There are a variety of industrial reaction conditions in which an active xylanase enzyme would be desired. As a result, xylanase enzymes with different activity profiles are of great interest.

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Screening mutant gene libraries for isolating improved enzyme variants is a powerful technique that benefits from effective and reliable biological expression systems. Pichia pastoris is a very useful organism to express proteins that are inactive in other hosts such as Escherichia coli and Saccharomyces cerevisiae. However, most P.

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