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Biomass from agriculture, forestry, and urban wastes is a potential renewable organic resource for energy generation. Many investigations have demonstrated that anaerobic fungi and methanogens could be co-cultured to degrade lignocellulose for methane generation. Thus, this study aimed to evaluate the effect of natural anaerobic fungi-methanogens co-culture on the methane production and lignocellulosic degradation of wastes from rice, corn and sugarcane. Hu sheep rumen digesta was used to develop a natural anaerobic fungi-methanogen co-culture. The substrates were rice straw (RS), rich husk (RH), corn stover (CS), corn cobs (CC), and sugarcane baggage (SB). Production of total gas and methane, metabolization rate of reducing sugar, glucose, and xylose, digestibility of hemicellulose and cellulose, activity of carboxymethylcellulase and xylanase, and concentrations of total acid and acetate were highest (P < 0.05) in CC, moderate (P < 0.05) in RS and CS, and lowest (P < 0.05) in SB and RH. The pH, lactate and ethanol were lowest (P < 0.05) in CC, moderate (P < 0.05) in RS and CS, and lowest (P < 0.05) SB and RH. Formate was lowest (P < 0.05) in CC, RS and CS, moderate (P < 0.05) in SB, and lowest (P < 0.05) in RH. Therefore, this study indicated that the potential of methane production and lignocellulosic degradation by natural anaerobic fungi-methanogens co-culture were highest in CC, moderate in RS and CS, and lowest in SB and RH. [ABSTRACT FROM AUTHOR]

Dehydration of wet bacterial cellulose (BC) mainly focuses on the physical characteristic or mechanical strength, but its polymorph crystal structure and thermal properties were rarely discussed. Herein, this study utilizes the drying method of hot-pressed and freeze-dried to the wet BC to elucidate the BC polymorph crystal structure in correlation with the BC crystallinity and thermal properties. The results indicate that dehydration of BC using hot-pressed (BC-HP) method reduced the cellulose Iα allomorph fraction by ± 5.0%, increased the crystallinity by ± 5.0%, but lower in thermal stability compared to freeze-dried (BC-FD) method. Additionally, BC-HP shows an exothermic reaction of melting at lower enthalpy value which is contradict to BC-FD and plant cellulose that presented an endothermic reaction with higher enthalpy values. Thus, investigation on BC polymorph crystal structure and thermal properties may offer an important role to regulate the desired characteristic of the dried BC. [ABSTRACT FROM AUTHOR]

Jatropha oil-based polyurethane acylate gel polymer electrolyte was mixed with different concentrations of tetrabutylammonium iodide salt (TBAI). The temperature dependences of ionic conductivity, dielectric modulus and relaxation time were studied in the range of 298 to 393 K. The highest ionic conductivity of (1.88 ± 0.020) × 10–4 Scm−1 at 298 K was achieved when the gel contained 30 wt% of TBAI and 2.06 wt% of I2. Furthermore, the study found that conductivity-temperature dependence followed the Vogel-Tammann Fulcher equation. From that, it could be clearly observed that 30 wt% TBAI indicated the lowest activation energy of 6.947 kJ mol−1. By using the fitting method on the Nyquist plot, the number density, mobility and diffusion coefficient of the charge carrier were determined. The charge properties were analysed using the dielectric permittivity, modulus and dissipation factor. Apart from this, the stoke drag and capacitance were determined. [ABSTRACT FROM AUTHOR]

Estimating the sizes of key populations at risk for HIV is crucial for HIV prevention and treatment. We provide findings of population size estimates (PSE) of males who inject drugs (MWID) in Myanmar, provide an intuitive method for countries to extrapolate subnational estimates into national estimates and provide guidance on how to maximize the utility of current PSE techniques. We used unique object and service multipliers, and successive sampling PSE in conjunction with a respondent driven sampling survey of MWID in ten Myanmar townships in 2014. Township estimates were assessed at a stakeholder meeting for biases and coded into ranges of high, medium and low MWID prevalence areas. Using the sampled townships as benchmarks for a range of MWID proportion estimates, national level MWID size estimates were derived by multiplying the adult male population for all townships with their corresponding proportion estimates. Final PSE ranged from high (4.12%), medium (1.02%) and low (0.11%), with the final agreed national point estimate of 83,000 MWID. Using estimates from survey data, this can translate into actual numbers of MWID living with HIV and practicing risky injecting and sexual behaviors. Although PSE are vital for monitoring HIV epidemics, no guidance exists for interpreting results of different PSE techniques or for extrapolating these results into national estimates. Assessing bias and gaining consensus on township level estimates and deriving ranges of MWID PSE throughout the country using stakeholder input is intuitive and accessible to countries. [ABSTRACT FROM AUTHOR]

Renewable polyol is of increasing interest as a building block in biomedical elastomer for bearing biodegradable ester group and immaculate functionality. Derived from non-edible vegetable oil, a new class of elastomer was successfully functionalized with MDI and TDI. Crosslink densities were varied by regulating ratio of hydroxyl to diisocyanate ( r) at 1/1.0, 1/1.1, and 1/1.2. Produced elastomers were examined by crosslink density, attenuated total reflectance Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, tensile testing, and scanning electron microscopy. The obtained elastomers had subambient glass transition temperature ( T ) suggested majority soft segment that acted as a continuous phase with intermediate phase separation. Medium conversion at gel point had enhanced physical properties. Highly elastic mechanical behavior was afforded from combination of side chains and high molecular weight polyol. At r = 1/1.2, MDI-based elastomer showed twofold improvement in Young modulus at slight expense of elongation. TDI-based elastomer accomplished elongation beyond 162%. Branching allophanate and biuret resisted early thermal breakdown by elevating activation energy. Frequency response and kinetic of thermal degradation provided beneficial perspective for elastomer characterization. The vegetable oil-based polyurethane was found able to resemble most of the physical properties of polycaprolactone (PCL)-derived polyurethane. Graphical Abstract: [ABSTRACT FROM AUTHOR]

In the original article there were errors in the methods section. Thus, within Table 1: (i) the primer sequence pair for SOD-2 was incorrectly cited; (ii) the primer sequence pair used for SOD 1 was incorrect and did not target the gene of interest. Additional experiments were performed with correctly designed SOD1 primer pair and the outcomes documented here. [ABSTRACT FROM AUTHOR]

Sein Win [5] obtained some degree conditions for the existence of a spanning tree with bounded maximum degree in a graph. Y. Caro, I. Krasikov and Y. Roditty [2], and, I. Krasikov and Y. Roditty [4] extended his results giving lower bounds for the size of largest tree with bounded maximum degree. We further extend the results by considering all trees with bounded maximum degree which are maximal with respect to the inclusion of vertex set. We then characterize the graphs which meet the bounds. Also, we obtain lower bounds for all maximal trees with bounded maximum degree in the graphs which satisfy a certain structure condition, as a generalization of G. Fan's condition [3] for hamiltonicity. [ABSTRACT FROM AUTHOR]