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An avirulent, live transconjugant Shigella hybrid (LTSHΔ stx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔ stx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1β and IL-23 in peritoneal mice macrophages indicated that LTSHΔ stx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔ stx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔ stx immunoglobulin. These studies suggest that the LTSHΔ stx could be a new live oral vaccine candidate against shigellosis in the near future. [ABSTRACT FROM AUTHOR]

Crushing mechanism plays a vital role in liberation of coal macerals (organic constituents), which aid in coke making. Due to the use of impact mills, vitrinite maceral grains shatter and participation in coke making is reduced. To address this issue, a new crushing machine based on a shear fracture mechanism has been developed and termed as coal shear crusher (CSC). It is shown that by using CSC one can take advantage of the viscoelastic property of vitrinite maceral. When compared to hammer mill, CSC processed coal showed improvement in plastic layer thickness (PLT), crucible swelling number (CSN), rank and coke strength after reaction (CSR) of the coal blends. Coals with vitrinite reflectance (Ro) greater than 1%, when processed using CSC showed greater improvement in coke properties as compared to coals with less than 1% Ro. Coal blend cost reduction can be effectively obtained if CSC technology is used, by increasing the portion of poor coking coal by replacing good coking coals. Present study scopes the utilization of up to 10% of CSC processed component in the coal blend, which is currently limited due to concerns related to coal cake stability which if overcome can increase the fraction of poor-coking coal in blends even further. [ABSTRACT FROM AUTHOR]

In this letter, we report the impact of epitaxial Gd2O3 on the electrical properties of an AlGaN/GaN high electron mobility transistor (HEMT) grown on a 150 mm diameter Si (111) substrate. Incorporation of epitaxial Gd2O3 grown by the molecular beam epitaxy technique under a metal gate (metal/Gd2O3/AlGaN/GaN) causes six orders of magnitude reduction in gate leakage current compared to metal/AlGaN/GaN HEMT. We observe that epi-Gd2O3 undergoes complete structural changes from hexagonal to monoclinic as the thickness of the layer is increased from 2.8 nm to 15 nm. Such structural transformation is found to have a strong impact on electrical properties whereby the gate leakage current reaches its minimum value when the oxide thickness is 2.8 nm. We find a similar trend in the density of interface traps (Dit) having a minimum value of 2.98 × 1012 cm−2 eV−1 for the epioxide layer of thickness 2.8 nm. Our measurements also confirm a significant increase in the two dimensional electron gas (2DEG) density (∼40%) at AlGaN/GaN interface with epioxide grown on AlGaN, thus confirming the contribution of epitaxial lattice strain on 2DEG modulation. [ABSTRACT FROM AUTHOR]

The separation of vitrinite is being primarily carried out through density-gradient concentration (DGC) method. However, this technology is limited to laboratory-scale operations, since gravity plays a trivial role in the separation of ultrafine particles. In the present investigation, processing of vitrinite macerals on a large scale was explored using column flotation. Two coal samples (medium coking and non-coking) of less than 500 µm size were processed at neutral pH in single-stage column operation. Column-flotation operating parameters such as air flow rate, collector, and frother dosage were optimized to obtain the maximum recovery of vitrinite maceral. Enrichment of vitrinite in flotation products was confirmed through petrography studies with respect to feed. The column-flotation results were compared against to theoretical value obtained from sink-and-float analysis. The extent of vitrinite enrichment using flotation column was further investigated through surface-characterization techniques such as contact angle, zeta potential, and Fourier transform-infrared spectroscopy. The column-flotation results showed that the maximum yield was 67% and 77.5% for Coals A and B and the corresponding recovery was 84% and 93%, respectively. [ABSTRACT FROM AUTHOR]

Pseudomonas putida is an uncommon opportunistic pathogen, usually susceptible to antimicrobial agents. Data concerning resistance to antimicrobial agents in clinical P. putida isolates are limited. To the best of our knowledge we report for the first time the isolation of NDM-1 -producing multidrug-resistant P. putida from a case of acute gastroenteritis. The isolate showed resistance to a wide range of antimicrobials, including fluoroquinolones, third-generation cephalosporins and carbapenems. The isolate also exhibited multiple mutations in the quinolone resistance determining region and showed the presence of qepA , bla TEM , bla OXA1 and bla OXA7 genes. The present study highlights the importance of looking for the relatively rare aetiological agents in clinical samples that do not yield common pathogens. [ABSTRACT FROM AUTHOR]