Safety assessment and evaluation of probiotic potential of bacteriocinogenic Enterococcus faecium KH 24 strain under in vitro and in vivo conditions

In the present investigation, a previously isolated Enterococcus faecium KH 24 strain was evaluated for the presence of virulence determinants (agg, esp, efaAfm, gelE, cylA, cylB, clyM, cpd, cob, ccf, ace and hyl), sensitivity to various antibiotics and production of biogenic amines. No virulence determinants were detected, except efaAfm. KH 24 was found to be sensitive to most of the tested antibiotics and none of the biogenic amines were produced by it. Moreover, KH 24 showed good in vitro tolerance to biological barriers and furthermore, its survival in gut of mice was also evaluated. Mice group fed with E. faecium KH 24 strain showed better weight gain and nearly 1 log cfu/g decrease in Salmonella enteritidis counts in the intestines as compared to control (p < 0.05). Enhanced growth of lactobacilli (p < 0.05) and decrease in coliform counts (p < 0.05) were also observed in test group. E. faecium KH 24 is, therefore, found to be a safe strain and it may be used as protective culture or as a probiotic in food preparations.     

Controlled synthesis of carbon nanostructures using aligned ZnO nanorods as templates

By combining in situ X-ray photoemission spectroscopy, ex situ high resolution transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy, we show that chemical vapor deposition (CVD) on vertically aligned ZnO nanorods can synthesize different carbon nanostructures (CNs), whose morphology is driven by the ZnO nanorods and whose dimensions and structures change as a function of the process temperature. The CNs range from amorphous carbon cups, completely covering the nanorods, to high density one-dimensional carbon nano-dendrites (CNDs), which start to appear like short hairs on the ZnO nanorods. The nanorods are partially etched when the process is done at 630–800 °C, while they are completely etched at temperatures higher than 800 °C. In the latter case, CNDs emerge from a porous carbon sponge formed at the substrate interface but they are preferentially aligned along the location of the pristine ZnO nanorods. When used as a chemiresisitor the CND–ZnO structures have a higher sensitivity to ammonia compared to chemiresistors made by bare ZnO nanorods, to other one-dimensional CNs, like carbon nanotubes or other metal/metal-oxides hybrid CNs.     

Effect of Amorphous Content on Dissolution Characteristics of Rifampicin

Rifampicin, one of the main first line anti-TB drugs, shows variable bioavailability in different marketed preparations and reasons cited include physiological, degradation, manufacturing/ processing, solid state, and bioavailability assessment procedure. Although the amorphous form of a drug is expected to exhibit higher solubility, the amorphous rifampicin has been reported to have a solubility disadvantage as compared to crystalline form II, which is used in marketed preparations. Amorphous form was generated and characterized by solid-state characterization techniques. Physical powder mixtures of form II with varying amounts of amorphous form were prepared, which were then subjected to solid-state characterization techniques and further evaluated for their dissolution behavior. Differential scanning calorimetry (DSC) scans show that area enclosed by integral of melting endotherm can be used for quantification of crystalline component, which can then be used to estimate amorphous content. No definite trend was evident in powder dissolution of mixtures that could implicate solubility difference of amorphous form. Intrinsic dissolution rate (IDR) results indicate that amorphous content has no effect on dissolution profiles of crystalline rifampicin.     

120 keV Ar ion-induced red and blue shift of SPR Wavelength of Au nanoparticles in fullerene C60

Journal of Materials Science: Materials in Electronics - Au nanoparticles are synthesized in a fullerene C60 matrix using the thermal co-evaporation technique. Fullerene C60 is chosen due to its...     

Numerical simulations of cracked plate using XIGA under different loads and boundary conditions

This article deals with the numerical simulation of cracked plate using extended isogeometric analysis (XIGA) under different loads and boundary conditions. The plate formulation is done using first-order shear deformation theory. The crack faces are modeled by the Heaviside function, whereas the singularity in stress field at the crack tip is modeled by crack tip enrichment functions. The stress intensity factors for the cracked plate are numerically computed using a domain-based interaction integral. The results obtained by XIGA for the center and edge crack plate are compared with extended finite element method and/or literature results for different types of loads and boundary conditions.     

Photodeposition of Ag and Cu binary co-catalyst onto TiO2 for improved optical and photocatalytic degradation properties

This paper deals with the influence of binary co-deposition of Ag and Cu metals on TiO₂ photocatalyst to investigate its adsorption, optical and photocatalytic properties relative to monometallic (Ag/Cu) deposition. Hence, different proportion of Ag and Cu has been simultaneously deposited on TiO₂ in an inert (argon) atmosphere under UV irradiations. It was found that the plasmonic absorption bands appeared in the visible region (480 and 640?nm for Ag and Cu, respectively) due to the binary deposition of Ag-Cu nanoparticles (～9–20?nm) onto TiO₂ surface as revealed by TEM size analysis and EDS/elemental mapping. The fluorescence spectrum of Ag-Cu-TiO₂ showed higher quenching of emission peak intensities at λ?>?450?nm in a different extent due to efficient charge separation as compared to respective monometallic (Ag/Cu)-TiO₂ nanocomposites. The photocatalytic activities of binary Ag-Cu-TiO₂ for the degradation of methylene blue and salicylic acid under UV and visible irradiations were found to be notably higher than monometallic deposited TiO₂. The reaction rates and CO₂ formation exhibited due to binary deposition always gives enhanced photoactivity which could be useful for removal of toxic environmental pollutants under solar radiations.     

Plague: A Challenge for Urban Crisis Management

The return of Plague, an unforgotten scourge of mankind, once again reminds us that it continues to smoulder in populations of wild rodents in natural foci throughout the world. Its occasional outbreaks remind one of the devastation it caused in the past. The 1994 outbreak in Surat caused local panic (mass hysteria) and international concern, leading to the imposition of travel and trade restrictions by a number of countries. The authenticity of the crucial decision in declaring the epidemic as ‘Plague’ and, later, different institutional initiatives taken for isolating the germ (Y. pestis) were subject to many controversies. The uniqueness of an extra band in its protein profile created much speculation among the media. This gave momentum to various notions, as to whether the disaster was natural or man‐made. In spite of all these short‐comings, the decision came to identify the epidemic as Plague and the entire catastrophic incidence was controlled within a week, with a low mortality rate. This paper traces the chronological evolution of the Plague epidemic and analyses the critical issues of its management, undertaken by various authorities and individuals, including a common citizenary. The emerging key issues of this catastrophic incident are discussed and an anatomy of the crisis is presented. The lessons learnt are put towards a model for strengthening long‐term planning against any such sudden natural or man‐made disaster.     

Infrastructure Challenges Caused by Industrial Transformation to Achieve Greenhouse Gas Neutrality. Ammonia Production in the Antwerp-Rotterdam-Rhine-Ruhr Area

Several pathways for potentially greenhouse gas neutral production of ammonia have been investigated compared to today's conventional ammonia production at chemical sites in Antwerp, Dormagen, and Geleen. These pathways include on-site water electrolysis using grid electricity, off-site production via water electrolysis using renewable electricity and supply of green hydrogen to the site, pyrolysis of natural gas and conventional ammonia production coupled with CO₂-capture on-site and transport to a storage site. All pathways effectively eliminate scope 1 emissions present in conventional production but continue to emit scope 2 emissions from grid electricity consumption. Eventually, a coordinated industry-wide and cross-industry effort is needed to address the transformational changes and develop the common cross-border infrastructures.     

Dynamic Cell and Microparticle Control via Optoelectronic Tweezers

This paper reports on cell and microparticle manipulation using optically induced dielectrophoresis. Our novel optoelectronic tweezers (OET) device enables optically controlled trapping, transportation, and sorting via dielectrophoretic forces. By integrating a spatial light modulator and using direct imaging, arbitrary dynamic manipulation patterns are obtained. Here, we demonstrate manipulation functions, including particle collectors, single-particle traps, individually addressable single-particle arrays, light-defined particle channels, and size-based particle sorting. OET-induced particle manipulation velocities are analyzed as a function of the applied voltage, optical pattern linewidth, and single-particle trap dimensions.     

Comparative study of the electronic structure of natural and synthetic rubies using XAFS and EDAX analyses

We have studied the Cr-K-edge XANES and EXAFS in natural Indian rubies from two sources and a synthetic ruby at ESRF. Weight % of various constituents in them is determined using EDAX measurements. Taking the results from the three techniques together we are able to demonstrate their feasibility in quantitative study of precious stones.