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In this study, the influence that the monomer composition of hydroxyethyl caprolactone acrylate/methyl methacrylate (HECLA/MMA) has on the properties of the latex films, including contact angle, thermogravimetric analysis, and mechanical properties was evaluated. The polymerization process to obtain small particle sizes, good colloidal stability, and polymer films was optimized through the use of pullulan (Pull) and different ratios of HECLA and MMA. The results revealed a substantial impact of the monomer composition and polymerization processes on the particle size and latex film properties. The use of seed latex obtained in situ reduces particle size and particle size distribution. Additionally, it was observed that the contact angle of the polymer films increased as the concentration of HECLA increased. Furthermore, the water absorption of the polymer films exhibited a decreasing trend after reaching an 80/20 monomer composition of HECLA/MMA. An increase in HECLA contents in the recipe showed a reduction in tensile strength, elastic modulus, hardness, and elongation at break. Conversely, higher HECLA contents contributed to improving the thermal properties of the polymer films. Finally, the optimal ratio of HECLA/MMA to improve the thermal degradation and tensile mechanical properties of the polymer film was 50/50 wt%. The results found in this work allow additional data for producing poly(HECLA-co-MMA)-g-Pull latexes by manipulating the ratios of HECLA and MMA, which can create new potential applications in various industrial settings for a wide range of polysaccharides. Highlights * Poly(HECLA-co-MMA)-g-Pull with different ratios of HECLA/MMA were successfully obtained. * The use of Pull after molar mass reduction had a significant effect on colloidal stability. * A reduction in tensile strength and elongation at break was obtained by increasing the amount of HECLA. * Thermal stability of the latex films showed a direct relationship with the content of HECLA. * Poly(HECLA-co-MMA)-g-Pull latexes can be used in agricultural applications. KEYWORDS emulsion polymerization, hydroxyethyl caprolactone acrylate, latex, thermal stability and mechanical properties, 1 | INTRODUCTION In recent years, there has been a growing demand for the formulation and enhancement of polymer latex exhibiting superior degradation capability as an alternative for agriculture applications. [...]

To achieve ecofriendly aerogels with high mechanics and fire resistance, naturally-occurring pea starch was employed as the major substrate, and starch-based composite aerogels were fabricated by freeze-drying method. The corresponding hydrogels were obtained through successive gelatinization/ dissolution of pea starch and polyvinyl alcohol (PVA), formation of precursor hydrogels via cyclic freeze-thawing, followed by treatment with borax aqueous solution. Borax treatment not only results in aerogels with high mechanics, but also endows the aerogels flame-retardant property. The final aerogels show high compression-resistance, with a maximum specific compressive modulus achieved at ~44 MPa and the yield strength 665 kPa, owing to the formation of a multi-crosslinked hybrid network. The maximum limiting oxygen index (LOI) of the aerogels exceeds 34. The peak heat release rate, the heat release capacity, and the total heat release decrease 74.5%, 76.2%, and 73.8% after borax treatment. Moreover, the obtained aerogels demonstrate good thermal stability and thermal insulation. The good performance is conducive for practical application. KEYWORDS aero, flame retardance, gels, mechanical properties, polysaccharide, polyvinyl alcohol, 1 | INTRODUCTION Aerogel is a kind of solid foam materials obtained by replacing the liquid inside the wet gels (called hydrogels when the liquid is water) with gas, while [...]

Grassland set-asides (GLSA) are fields that are taken out of intensive annual crop production and seeded with a mixture of grasses and legumes for one to four years to improve soil quality. The objectives of this study were to evaluate (i) the relationships among soil organic carbon (SOC), permanganate oxidisable C (POXC), dilute-acid extractable polysaccharides (DAEP) and aggregate stability to determine if they may be used as proxies for one another, (ii) whether these indicators could be used to predict aggregate stability, (iii) if differences in soil quality after shortterm GLSAs, detected with aggregate stability, could instead be detected with POXC or DAEP and (iv) potential use of diffuse Fourier transform spectroscopy (FT-MIR) to predict POXC, DAEP and aggregate stability in the Fraser River Delta region of British Columbia, Canada. There were strong relationships among SOC, POXC and DAEP, but the relationship between DAEP and SOC ([R.sup.2] = 0.60, P < 0.0001) was less strong than that observed between POXC and SOC ([R.sup.2] = 0.71, P < 0.0001). All three soil C fractions were significantly predicted with the 2-6 mm aggregate size fraction but the correlations for DAEP ([R.sup.2] = 0.43) and POXC ([R.sup.2] = 0.36) were stronger than that for SOC ([R.sup.2] = 0.29). Predictions of soil quality indicators using FT-MIR produced [R.sup.2] = 0.92 for POXC, [R.sup.2] = 0.93 for DAEP and [R.sup.2] = 0.62 for the 2-6 mm aggregate size fraction. These results suggest that FT-MIR holds promise as a low-cost method to determine labile soil C fractions that are better proxy soil quality indicators for aggregate stability than SOC. Additional keywords: agriculture, labile carbon fractions, permanganate oxidisable carbon, perennial grass systems, soil polysaccharides, soil structure. Received 5 July 2019, accepted 3 February 2020, published online 31 March 2020, Introduction Soil quality is a concept commonly used to evaluate sustainable and beneficial land management practices in agricultural systems, and the most widely acknowledged indicator of soil quality is soil [...]

The dense microbial ecosystem in the gut is intimately connected to numerous facets of human biology, and manipulation of the gut microbiota has broad implications for human health. In the absence of profound perturbation, the bacterial strains that reside within an individual are mostly stable over time.sup.1. By contrast, the fate of exogenous commensal and probiotic strains applied to an established microbiota is variable, generally unpredictable and greatly influenced by the background microbiota.sup.2,3. Therefore, analysis of the factors that govern strain engraftment and abundance is of critical importance to the emerging field of microbiome reprogramming. Here we generate an exclusive metabolic niche in mice via administration of a marine polysaccharide, porphyran, and an exogenous Bacteroides strain harbouring a rare gene cluster for porphyran utilization. Privileged nutrient access enables reliable engraftment of the exogenous strain at predictable abundances in mice harbouring diverse communities of gut microbes. This targeted dietary support is sufficient to overcome priority exclusion by an isogenic strain.sup.4, and enables strain replacement. We demonstrate transfer of the 60-kb porphyran utilization locus into a naive strain of Bacteroides, and show finely tuned control of strain abundance in the mouse gut across multiple orders of magnitude by varying porphyran dosage. Finally, we show that this system enables the introduction of a new strain into the colonic crypt ecosystem. These data highlight the influence of nutrient availability in shaping microbiota membership, expand the ability to perform a broad spectrum of investigations in the context of a complex microbiota, and have implications for cell-based therapeutic strategies in the gut.Finely tuned control of strain engraftment and abundance in the mouse gut microbiota was achieved using the marine polysaccharide porphyran, which could exclusively be used by an introduced subset of wild-type or genetically modified Bacteroides strains., Author(s): Elizabeth Stanley Shepherd [sup.1] [sup.2] , William C. DeLoache [sup.2] , Kali M. Pruss [sup.1] , Weston R. Whitaker [sup.2] , Justin L. Sonnenburg [sup.1] Author Affiliations:(1) Department of [...]

Permanent polysaccharide coating on gigaporous polystyrene (PS) microspheres was achieved through direct chemical grafting of dextran via a facile method, minimizing nonspecific adsorption of proteins and providing easily derivatizable groups on microspheres. Chloroacetylated PS microspheres (PS-CI) were first developed through acetylation, and hydrophilic dextran was directly grafted to hydrophobic PS-CI via a Williamson reaction (PS-Dex). The homogeneous side-bound dextran coating has the advantage of masking the hydrophobic surface of the PS microspheres, while maintains their original gigaporous structure. After grafting, the hydrophobic surface of the PS microspheres was effectively masked, and nonspecific protein adsorption was greatly reduced. Moreover, the hydroxyl-rich coating can be easily derivatized through classical chemical methods. A column packed with PS-Dex presented both good permeability and mechanical strength at high flow velocities of up to 3612 cm/h. These results implied that PS-Dex should be an ideal matrix for high-speed protein chromatography., INTRODUCTION Downstream processing in modern biotechnology, as represented by large-scale purification and separation of biomolecules, consumes up to 70% or more of the total processing cost in the production of [...]

A study was conducted to ascertain the efficacy of the Vi polysaccharide typhoid vaccine when administered to children less than 5 years of age. Results revealed that the vaccine was effective in young children as well as protected the unvaccinated neighbors of vaccinees and should be used in areas where typhoid is endemic.

An ultrasensitive electrical detection method of nucleic acids has been developed on a nanogapped biosensor. In this study, peptide nucleic acid (PNA) probes were immobilized in the gaps of a pair of finger microelectrodes first and were then hybridized with their complementary target DNA. After that, pectin molecules were introduced into the DNA strand via zirconium-phosphate and zirconium-carbonate chemistries and were oxidated by periodate in acetate buffer (pH 3.98). The newly produced aldedyde groups act as a reactant to reduce ammoniacal silver ion to produce silver nanoparticles, which bridged the gap of the interdigitated microelectrode. The conductance of the metallic nanoparticles correlated directly with the amount of the hybridized DNA. A much higher sensitivity was achieved at 3 femtomolar (S/N > 3) under optimal conditions. This biosensor is also applicable to the direct detection of RNA.

Conventional analytical methods available for measuring total nonstructural carbohydrate (TNC) concentrations in turfgrasses are not suitable for nondestructive and routine in-field evaluations. The objectives of this study were to examine the utility of near infrared reflectance spectroscopy (NIRS) to analyze the concentrations of glucose, fructose, sucrose, and fructan in creeping bentgrass {Agrostis palustris Huds. [= A. stolonifera var. palustris (Huds.) Farw.]} clippings and to determine the effect of sample collection and preparation techniques on TNC content. Samples were collected from a field experiment and subjected to different post-clipping sampling techniques to determine the stability of carbohydrate components through sample processing. Instant freezing in liquid nitrogen, rapid cooling in a dry ice chamber, and ambient temperature collection techniques were examined. TNC and fructan concentrations, analyzed by NIRS, were 19 and 9% higher in samples treated with liquid nitrogen and held in dry ice followed by freeze-drying than the uther sampling techniques. Calibration equations were obtained by modified partial least square (PLS) regression analysis of conventional laboratory analysis values on 97 selected NIR spectra using a scanning monochromator NIR spectrophotometer and WinISI computer software. Calibration equations were externally validated with 15 additional samples. The standard errors of calibration (SEC) were 1.3, 1.9, 1.0, 4.3, and 7.1 mg [g.sup.-1] for glucose, fructose, sucrose, fructan, and TNC, respectively. Predicted and observed concentrations of all TNC components in all validation sets were highly correlated ([r.sup.2] > 0.90), except once for sucrose ([r.sup.2] 0.59). We conclude that NIRS can analyze the TNC concentration of creeping bentgrass clippings more conveniently and faster than conventional analytical techniques. The results indicate that NIRS can determine TNC and its component concentrations in different creeping bentgrass cultivars with good accuracy., THE USE OF CONVENTIONAL ANALYTICAL METHODS for measuring TNC components, such as glucose, fructose, sucrose, and fructans, are often laborious and time-consuming. Screening a large number of samples would benefit [...]

Objective: To investigate the relationship between the percentage of energy from fat and food and nutrient intakes at 18 and 43 months of age. Design: Diet was assessed using a 3 day unweighed food record. The children were divided into quartiles of fat intake as a percentage of energy (QFI), and food and nutrient intakes in the different QFIS were compared. Subjects: A total of 1026 children at 18 months and 863 children at 43 months, taking part in the Avon Longitudinal Study of Pregnancy and Childhood, participated. Results: At 18 months the mean (s.d.) fat intake was 31.2 (2.8) % of energy in the lowest QFI and 43.1 (2.2) % in the highest. Energy intake increased slightly with increasing QFI. The percentage of energy derived from total sugar, and in particular nonmilk extrinsic sugar fell as QFI increased, as did the ratio of polyunsaturated to saturated fatty acids. Intakes of retinol equivalents and zinc increased significantly with increasing QFI, while intakes of iron and most water soluble vitamins fell. There was a particularly marked fall in vitamin C intake as fat intake increased, from 11.8 mg/MJ in the lowest QFI, to 6.0 mg/MJ in the highest (P < 0.001). Consumption of whole milk increased substantially with percentage energy from fat, from 51 g/MJ in the lowest QFI to 116g/MJ in the highest (P Conclusions: The chances of a suboptimal intake of zinc and retinol were higher at lower fat intakes. However, intakes of the fatsoluble vitamins E and D were unrelated to fat intake and intakes of iron and vitamin C fell as fat intakes increased. Some suggestions for improving diet in this age group have been given. Sponsor: University of Bristol. DOI: 10.1038/sj/ejcn/1601335 Keywords: fat; micronutrients; iron; vitamin C; food groups; milk; pre-school children, Introduction A certain level of fat is vital in any diet, as a source of essential fatty acids and fat-soluble vitamins. It also has the advantage of carrying considerable amounts [...]