Green synthesis and antimicrobial activity of silver nanoparticles using wild medicinal mushroom Ganoderma applanatum (Pers.) Pat. from Similipal Biosphere Reserve,Odisha, India

In the present study, green synthesis and cost effective approach of silver nanoparticles using wild medicinal mushroom Ganoderma applanatum (Pers.) Pat. from Similipal Biosphere Reserve, Odisha, India is reported. The biosynthesised AgNPs were characterised using UV‐visible spectroscopy, particle analyser and scanning electron microscopy studies. It was found by dynamic light scattering analysis, that the average size and charges of the AgNPs were 133.0 ± 0.361 nm and −6.01 ± 5.30 mV, respectively. Moreover, the Fourier transform infrared study was also conducted to identify the biomolecules or functional groups responsible for the reduction of Ag and stabilisation of the AgNPs. The potential biomedical application with reference to antimicrobial activity of the synthesised AgNPs was investigated against some pathogenic microorganisms viz. Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, Vibrio cholerae, Staphylococcus aureus and Shigella flexneri.Inspec keywords: antibacterial activity, biomedical materials, nanomedicine, nanofabrication, materials preparation, ultraviolet spectra, visible spectra, scanning electron microscopy, Fourier transform infrared spectra, molecular biophysics, reduction (chemical), biochemistry, microorganisms, silver, nanoparticlesOther keywords: green synthesis, antimicrobial activity, silver nanoparticles, wild medicinal mushroom, Ganoderma applanatum Pat, Similipal Biosphere Reserve, Odisha, UV‐visible spectroscopy, particle analyser, scanning electron microscopy, dynamic light scattering analysis, Fourier transform infrared study, biomolecules, functional groups, silver reduction, AgNP stabilisation, biomedical application, pathogenic microorganisms, Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, Vibrio cholerae, Staphylococcus aureus, Shigella flexneri, Ag

Abbreviations

AgNPs

‐ Silver Nanoparticles

SPR

‐Surface plasmon resonance

AgNO3

‐Silver nitrate

nm

‐ Nanometer

mm

‐Milimetre

     

Automatic clustering algorithm based on multi-objective Immunized PSO to classify actions of 3D human models

Multi-objective clustering algorithms are preferred over its conventional single objective counterparts as they incorporate additional knowledge on properties of data in the from of objectives to extract the underlying clusters present in many datasets. Researchers have recently proposed some standardized multi-objective evolutionary clustering algorithms based on genetic operations, particle swarm optimization, clonal selection principles, differential evolution and simulated annealing, etc. In many cases it is observed that hybrid evolutionary algorithms provide improved performance compared to that of individual algorithm. In this paper an automatic clustering algorithm MOIMPSO (Multi-objective Immunized Particle Swarm Optimization) is proposed, which is based on a recently developed hybrid evolutionary algorithm Immunized PSO. The proposed algorithm provides suitable Pareto optimal archive for unsupervised problems by automatically evolving the cluster centers and simultaneously optimizing two objective functions. In addition the algorithm provides a single best solution from the Pareto optimal archive which mostly satisfy the users' requirement. Rigorous simulation studies on 11 benchmark datasets demonstrate the superior performance of the proposed algorithm compared to that of the standardized automatic clustering algorithms such as MOCK, MOPSO and MOCLONAL. An interesting application of the proposed algorithm has also been demonstrated to classify the normal and aggressive actions of 3D human models.     

Variability of mesopause temperature derived from two independent methods using meteor radar and its comparison with SABER and EOS MLS and a collocated multi-wavelength dayglow photometer over an equatorial station,Thumba (8.5° N, 76.5° E)

Two independent methods for deriving mesopause temperature using meteor radar installed at an equatorial station, Thumba (8.5° N, 76.5° E), are discussed in this article. This meteor radar-derived mesopause temperature is then compared with two different types of spaceborne measurement, namely (i) Sounding the Atmosphere using Broadband Emission Radiometry (SABER) and (ii) the Earth Observing System Microwave Limb Sounder (EOS MLS), and a collocated multi-wavelength dayglow photometer (DGPM). The meteor radar-derived temperature is in fairly good agreement with all the three measurement techniques, with an uncertainty of ±10°. This study focuses on a detailed evaluation and inter-comparison of mesopause temperature derived from different measurement techniques. An attempt is also made to compare the suitability of these observations to study planetary waves and other oscillation activities in the mesospheric region.     

Harnessing the sun for an evergreen revolution: a study of solar-powered irrigation in Bihar,India

In 2012, the government of Bihar revived 34 non-functioning public tubewells using solar panels. The performance of 16 of these wells over 12 months was tracked and analyzed using data from tubewell operators and 240 farmers. Access to affordable irrigation from solar pumps led to a 9–10% increase in productivity of rice and wheat. Furthermore, in a severe drought, farmers could grow paddy in the entire area irrigated by solar pumps, when nearly 40% of other land was left fallow. Solar pumps can help increase crop productivity, reduce the cost of irrigation, and make agriculture more resilient to climate change.     

First report on observation of abnormal creep in a Zr–2.5wt.%Nb alloy at low stresses

Low-stress creep behaviour of a two-phase Zr–2.5%Nb alloy, differently heat treated, has been investigated using helical test specimens. The phase diagram of the α (hcp) + β (bcc) alloy is characterized by the monotectoid reaction at 893 ± 10 K: β ₁ → (α + β ₂) where β ₁ (Zr–20Nb) and β ₂ (Zr–80Nb) have widely differing compositions. At the creep testing temperature, 818 K, which is close to but below the monotectoid temperature, the creep rate for samples with the equilibrium α + β ₂ structure has been found to be considerably higher, over an order of magnitude, than that in samples with the metastable α + β ₁ structure. Microstructural changes accompanying the markedly enhanced creep rate for the α + β ₂ structure at stresses as low as 1–4 MPa have been explained in terms of the relative stability of the β ₁ and the β ₂ phases during the creep process. An attempt has been made to elicit the likely mechanism underlying the observed enhancement of creep rate and the changes in morphology, composition and volume fraction of the β phase.     

Short- and long-term effects of fraternity and sorority membership on heavy drinking: A social norms perspective.

This study sought to determine whether the well-established relation between fraternity/sorority (Greek) membership and heavy alcohol use persists beyond the college years and whether some common third variables might account for the relation between Greek status and heavy drinking. During each of 4 years of college and 1 additional year, young adults (N ?=?319) completed measures of alcohol use, personality, alcohol expectancies, and environmental influences on drinking. Throughout the college years, Greeks consistently drank more heavily than non-Greeks. Statistically controlling for previous alcohol use did not eliminate this effect. However, Greek status did not predict postcollege heavy drinking levels. Also, perceived peer norms for heavy drinking mediated the relation between Greek affiliation and heavy alcohol use. Results are discussed in terms of situational determinants of heavy alcohol involvement in young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Structural and electrical properties of TlLiWO4 ceramics

Abstracts are not published in this journal     

Experimental Studies on Damage Growth in Composites under Dynamic Loads

Experimental investigations have been carried out to study the dynamic damage growth in glass/polyester composites. Detonation of two PETN explosive charges on a modified single edge notch (MSEN) specimen provides the dynamic load in the form of a planar tensile wave. High speed photography is used to record the dynamic damage events. The results show that damage grows perpendicular to the loading direction, similar to the static growth; the damage zone splits analogous to the crack branching in unreinforced polyester. The damage propagation velocity in a composite is higher than the crack propagation velocity in polyester resin. The damage area grows at an average rate of 4.3 m²/sec. Static experiments show that about 4 percent of the total energy is spent on the fiber-matrix interface debonding. The damage zone under dynamic loads is much higher than under static loads.     

Spectral distribution of photocurrent in poly(6-tert-butyl-3-methyl-3,4-dihydro-2H-1,3-benzoxazine)

The spectral distribution of photoconductivity in poly(6-tert-butyl-3-methyl-3,4-dihydro-2H-1,3-benzoxazine) was studied in the sandwich configuration with indium tin oxide and silver electrodes. The photocurrent was found to originate mainly from the bulk dissociation of excitons with lesser contribution from electrode-mediated exciton dissociation. The molecule was fluorescent, but in the presence of the electron acceptor molecule 2,4,6-trinitrophenol (TNP), the intensity was reduced. The reduction in fluorescence intensity corresponded to an increase in photocurrent. The molecule showed photoconductivity in the visible without any sensitizers, which makes it suitable for stable photorefractive composites.