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An organic 4-aminopyridine monophthalate (PA4AP) single crystal grown by solvent evaporation at room temperature was studied for third-order nonlinear optical and antibacterial applications. The title material was found to crystallize in a non-centrosymmetric orthorhombic system with space group P212121, and the crystallographic information was acquired by its response to X-ray diffraction analysis. The functional groups and their different modes of vibration were studied by FTIR spectroscopy to identify the various chemical bonds present in PA4AP. Optical absorption study revealed less absorption in the visible region with an absorption cut-off wavelength at 315 nm, below which the material shows complete absorption. The title crystal was characterized for luminescence and based on this the inter-band structures were analysed for crystal defects. Mechanical and dielectric properties with an emphasis on solid-state parameters were investigated to understand the crystal stability for device applications. Kurtz–Perry powder analysis revealed that the PA4AP crystal has comparable second harmonic generation efficiency with the well-known KDP crystal. The third-order nonlinear optical susceptibility (χ(3)), nonlinear absorption coefficient (β) and nonlinear refractive index (n2) of title material were found to be 1.06 × 10−6 (esu), 6.51 × 10−5 (cm W−1) and 2.33 × 10−8 (cm2 W−1), respectively. The reverse saturable absorption observed in open aperture Z-scan indicates the suitability of PA4AP for optical limiting application. The antibacterial activity was investigated against few foodborne pathogens which show the antibacterial stability of PA4AP against Shigella flexneri and Vibrio cholerae bacteria. [ABSTRACT FROM AUTHOR]

The excitation function for the proton induced nuclear reactions on natural cadmium was measured up to 23 MeV employing stacked foil activation technique using the 14UD pelletron accelerator. Experimental cross-section and isomeric cross-section ratio have been measured for the nat Cd(p,x) 105 , 111 m Cd, nat Cd(p,x) 109 g , 110 m , 110 g , 111 m , 111 g , 112 m , 112 g , 113 m , 115 m , 116 m In reactions. The excitation function of 105 Cd and the isomeric cross-section ratio of 110 , 111 , 112 In isotopes have been measured and reported for the first time. Theoretical analysis of the data are done using the statistical model codes EMPIRE-3.2 and TALYS-1.8. Various dependence of isomeric cross-section ratio on different factors such as the spin, life time of the isomeric states and also the dependence of the exit channel are well explained. [ABSTRACT FROM AUTHOR]

In this study, Ni1−xZnxFe2O4 (x = 0, 0.25, and 0.5) nanoparticles were successfully synthesized via microwave-assisted combustion method and characterized by XRD, FTIR, and SEM–EDAX. XRD results enunciate that the nanoparticle crystallizes in cubic spinel structure with an average crystallite size (40.2, 37.2, 35.1 nm), and also, the lattice strain, specific surface area, X-ray density were evaluated. The morphology and chemical compositions of Ni, Zn, Fe, and O elements were confirmed by the SEM–EDAX studies. For all the samples, vibrational stretching modes of Mtetra–O site (597 (S1), 593 (S2), 583 (S3) cm−1) and Moctra–O site (416 (S1), 421 (S2), 422 (S3) cm−1) were related to the distribution of the cation Ni2+/Zn2+ and Fe3+ ions among the octahedral and tetrahedral sites. From the UV–Vis–DRS spectra, the optical energy band gap has been estimated to be 1.75–2.01 eV. The dielectric constant and loss were measured by varying the applied frequency (50 Hz to 200 kHz) at room temperature. The electronic polarizability (α) was calculated using Penn analysis, Clausius–Mossotti equation, and energy band gap value. Third-order nonlinear optical parameters such as the nonlinear absorption coefficients (10−5 cm/W), refractive index (10−9 cm2/W) and the third-order nonlinear susceptibilities (10−6 esu) were determined by Z-scan technique. The antibacterial studies were tested against Bacillus cereus, Staphylococcus aureus, Shigalla flexneri and Klebsiella pneumonia bacterial strains. The existing results point out that the synthesized Ni/Zn/Fe2O4 nanoparticles are possible candidates for photonic devices, optical switches, optical limiting and also for pharmaceutical applications. [ABSTRACT FROM AUTHOR]

The present study demonstrates the use of a transportable anechoic chamber for conducting microphone free-field calibrations with lowest levels of uncertainty. A dedicated transportable anechoic chamber (make SPEKTRA, Germany) of internal volume of 2 m3 completely lined with wedge-shaped absorbers is utilized for free-field calibrations in the frequency range of 125 Hz–20 kHz using the substitution method as per the IEC 61094-8 standard. The study has identified the usable working space inside a free-field chamber using the inverse-square pressure law, and the deviations from the inverse-square law of the free-field chamber are quantified. The measurement uncertainty of ± 0.36–0.52 dB (k = 2, 95% confidence level) is evaluated in the frequency range of 125 Hz–20 kHz and is validated in a bilateral comparison. The application of Monte Carlo simulation approach in the evaluation of measurement uncertainty in microphone free-field calibrations is also demonstrated. [ABSTRACT FROM AUTHOR]

Rice crop, a staple food for a majority of population across the world, holds a significant role to play in alleviating the global hunger problem. Enhancement of genetic diversity of rice will serve to overcome constraints in sustained and ecologically effective improvement in the production of quality rice, challenged by erratic patterns of global climate, changing pest dynamics, resource availability in proportion to growing population etc. Proton ion beam has sprung up as a promising novel mutagen in the mutation breeding of crop plants, by virtue of its higher LET values, causing higher frequency of mutations. Dose optimization is pre-requisite to obtain a range of phenotypic mutants, without drastic reduction in survival and growth subsequently. This study was undertaken to standardize proton beam irradiation dose rate post the evaluation of in-vitro germination, growth and survival of rice variety IBD -1, with doses ranging from 0-500Gy. Doses between 152.47Gy-253.53Gy were found suitable for mutagenesis, without drastically impairing growth and survival. [ABSTRACT FROM AUTHOR]

Nonlinear optical single crystals of L-lysine p-nitrophenolate monohydrate (LLPNP) were grown in aqueous solution by the slow evaporation solution technique (SEST). The grown crystals were subjected to powder X-ray diffraction analysis, (PXRD) and it was found that the title compound was crystallized in the orthorhombic crystal system with noncentrosymmetric space group of 212121. The vibrational frequencies of various functional groups present in the crystal were analyzed using the FTIR spectrum with a wavenumber range between 450 cm and 4000 cm. The microhardness analysis of the sample revealed that the crystal belongs to the soft material category. Piezoelectric analysis was performed to measure the value of the piezoelectric (d) coefficient. Blue light emission of the material was confirmed using the photoluminescence spectrum. Thermal stability of the grown crystal was analyzed using a melting point apparatus and it was found that the LLPNP is stable upto 175C. Etching analysis was performed at various durations, in order to identify the surface properties of the LLPNP crystal. [ABSTRACT FROM AUTHOR]

Organic single crystal of nicotinium tartrate (NT), an efficient nonlinear optical (NLO) material for frequency conversion, has been grown at a constant temperature at 40C within a period of 20 days by slow evaporation solution technique (SEST). Structural information and lattice dimensions were determined using powder X-ray diffractometer (PXRD) analysis. The functional groups and vibrational frequencies were identified using FTIR spectrum analysis with the range of 4000-450cm. Mechanical properties of the grown crystal were studied using Vickers microhardness tester. The optical properties of grown crystal were investigated using UV-Vis NIR spectrum analysis and it is confirmed that the crystal has very low absorption in the entire visible region. The dislocations and defects were studied by photoluminescence spectrum. The crystal has single stage melting, which was observed at 180C and there was no decomposition before its melting point. Piezoelectric, photoconductivity and chemical etching analysis have also been performed on the grown NT single crystals and the observed results were discussed. Nonlinear optical property of the material was measured using the powder Kurtz-Perry technique. [ABSTRACT FROM AUTHOR]

An organic nonlinear optical (NLO) single crystal of L-methioninium picrate (LMP) has been grown by slow evaporation solution technique (SEST) at a constant temperature of C. Formation of nucleation and growth kinetics of the crystal were observed using an optical microscope for different durations and it was found that the shape of nucleation is similar to the grown large size single crystals of the same material. The characterization techniques such as powder X-ray diffraction (PXRD) analysis, UV-Vis NIR, Vickers microhardness, piezoelectric d coefficient, photoconductivity and etching studies have been performed. The crystal system and lattice parameters of the grown crystal were determined by PXRD analysis. The spectroscopic properties of the synthesized compound were confirmed by Fourier transform infrared (FTIR) analysis. The UV-Vis NIR analysis was performed on the grown single crystal to find the optical absorption in the entire visible region. Attempts have been made to investigate the mechanical properties of LMP crystal using Vickers diamond pyramid indenter. In addition piezoelectric, photoconductivity and etching studies were carried out to study the d coefficient, photoconducting nature and surface properties respectively. [ABSTRACT FROM AUTHOR]

Organic nonlinear optical (NLO) single crystal of L-tartaric acid-nicotinamide (LTN) has been grown by slow evaporation solution technique at a constant temperature of 40C. The grown crystals were subjected to various characterization techniques in order to examine their suitability for various applications. Powder X-ray diffraction (PXRD) analysis revealed that the compound is formed without any impurities. Functional groups and formation of the title compound were confirmed using FTIR analysis. Optical behavior of the material was examined using UV-Vis NIR spectrum analysis and the lower cut-off wavelength and optical band gap energy were calculated. Microhardness, dielectric and piezoelectric studies have been carried out at ambient conditions. Electronic properties such as valence electron plasma energy, Penn gap, Fermi energy and electronic polarizability were calculated by Clausius-Mossotti relation. Photoluminescence analysis was carried out to study the luminescence nature of the crystal and its defect states. In addition photoconductivity, etching studies and powder Kurtz and Perry second harmonic generation (SHG) test were carried out. [ABSTRACT FROM AUTHOR]

White spot syndrome virus (WSSV) is the causative agent of a disease that causes severe mortalities in cultured shrimp worldwide. The sequence of five structural genes of an Indian isolate of WSSV was compared with sequences from other WSSV isolates deposited in GenBank. Among the structural genes analyzed, the sequences of vp28 and vp19 had maximum divergence with nucleotide changes at ten different positions from twenty eight submissions for vp28 and six changes from seventeen submissions for vp19. The vp68, vp26, and vp281 genes were found to be highly conserved between isolates. [ABSTRACT FROM AUTHOR]

Track etch membranes (TEMs) program at 14 UD Pelletron accelerator at TIFR, Mumbai, India using 25 micron thick polyethylene terepthalate film is described. Large scale preparation of TEMs by scanning heavy ion beams using a electromagnetic scanner and rolling mechanism using a geared D.C. motor and vacuum rotary feed through are presented. The selection of ions of suitable energy and etching parameters for making various pore sizes were investigated using Rutherford scattered beam from Pelletron accelerator. Pore size and pore density were measured using scanning electron microscope. Scanning width up to 35 cm and irradiation up to 22 m were successfully carried out using this facility. Some applications carried out using these membranes are also mentioned. [ABSTRACT FROM AUTHOR]

Water and post-larvae samples from black tiger ( Penaeus monodon) shrimp hatcheries; pond water, pond sediment and shrimp from aquaculture farms were screened for the presence of V. cholerae. A V. cholerae-duplex PCR method was developed by utilizing V. cholerae species specific sodB primers and ctxAB genes specific primers. Incidence of V. cholerae was not observed in shrimp hatchery samples but was noticed in aquaculture samples. The incidence of V. cholerae was higher in pond water (7.6%) than in pond sediment (5.2%). Shrimp head (3.6%) portion had relatively higher incidence than shrimp muscle (1.6%). All the V. cholerae isolates ( n = 42) belonged to non-O1/non-O139 serogroup, of which 7% of the V. cholerae isolates were potentially cholera-toxigenic ( ctx positive). All the ctx positive V. cholerae ( n = 3) were isolated from the pond water. Since, cholera toxin (CT) is the major contributing factor for c holera gravis, it is proposed that the mere presence of non-O1/non-O139 V. cholerae need not be the biohazard criterion in cultured black tiger shrimp but only the presence of ctx carrying non-O1/non-O139 V. cholerae may be considered as potential public health risk. [ABSTRACT FROM AUTHOR]

Aims: The genetic diversity of Vibrio cholerae isolated from black tiger shrimp ( Penaeus monodon) aquaculture farms was determined using three PCR typing methods based on enterobacterial repetitive intergenic consensus (ERIC) sequences, ribosomal gene spacer (RS) sequence and repetitive extragenic palindromic (REP) sequences. Methods and Results: Non-O1 and non-O139 V. cholerae isolates were obtained from shrimp pond water, pond sediment, shrimp head and shrimp muscle. RS-PCR yielded fewer bands than REP-PCR and ERIC-PCR. Higher similarity was observed in RS-PCR (75–100%) than in REP-PCR (60–95%) and ERIC-PCR (40–95%). Conclusions: A 100% similarity between V. cholerae isolates was only noticed in RS-PCR. The choleratoxigenic V. cholerae (non-O1 and non-O139) showed greater genetic similarity with ctx-negative V. cholerae than among ctx-positive V. cholerae. Significance and Impact of the Study: The greater similarity of ctx-positive V. cholerae with ctx-negative V. cholerae isolates indicates that the ctx-positive strains (non-O1 and non-O139) might have originated from autochthonous V. cholerae in the aquatic niche. [ABSTRACT FROM AUTHOR]

Aims: To determine the distribution of Salmonella serovars in seafood and to examine the intraserovar genetic variations in Salmonella enterica subsp. enterica serovar Rissen and Salmonella Weltevreden by polymerase chain reaction (PCR)-ribotyping and enterobacterial repetitive intergenic consensus (ERIC)-PCR methods. Method and Results: A total of 417 seafood samples collected over 2003–2006 from fishing harbours and fish markets of Cochin (India) was studied for presence of Salmonella serovars. Seafood samples were analysed for the presence of Salmonella by Bacteriological Analytical Manual (BAM), U.S. Food & Drug Administration (USFDA) method. The study indicated that 23·2% of the seafood samples were positive for Salmonella and a total of 241 Salmonella isolates comprising of 27 different serovars were isolated from seafood. S. Weltevreden, Salmonella Rissen, Salmonella Typhimurium and Salmonella Derby were found to be the most predominant serovars in seafood. PCR-ribotypes and ERIC-PCR profiles showed multiple genotypic profiles for S. Rissen and S. Weltevreden in seafood and the level of discrimination indices obtained was at 0·974 for S. Rissen and 0·988 for S. Weltevreden, respectively. Conclusion: The study highlighted the major Salmonella serovars in the seafood of Cochin (India) and molecular fingerprinting pattern revealed genetic variation among S. Rissen and S. Weltevreden. Significance and Impact of the Study: Widespread occurrence of Salmonella contamination in seafood and multiple clones of S. Rissen and S. Weltevreden detected in seafood, thus, indicated the diverse routes of Salmonella contamination in seafood. [ABSTRACT FROM AUTHOR]

Salmonella enterica subsp. enterica Typhimurium and Salmonella enterica subsp. enterica Derby strains isolated from different seafood were genotyped by PCR-ribotyping and ERIC-PCR assays. This study has ascertained the genetic relatedness among serovars prevalent in tropical seafood. PCR-ribotyping exhibited genetic variation in both Salmonella serovars, and ribotype profile (II) was most predominant, which was observed in 10/18 of Salmonella enterica subsp. enterica Typhimurium and 7/17 Salmonella enterica subsp. enterica Derby isolates. Cluster analysis of ERIC-PCR for Salmonella enterica subsp. enterica Typhimurium strains exhibited nine different banding patterns and four strains showed >95% genetic homology within the cluster pairs. ERIC-PCR produced more genetic variations in Salmonella enterica subsp. enterica Typhimurium; nevertheless, both methods were found to be comparable for Salmonella enterica subsp. enterica Derby isolates. Discrimination index of PCR-ribotyping for Salmonella enterica subsp. enterica Typhimurium isolates was obtained at 0.674 and index value 0.714 was observed for Salmonella enterica subsp. enterica Derby strains. Molecular fingerprinting investigation highlighted the hypothesis of diverse routes of Salmonella contamination in seafood as multiple clones of Salmonella enterica subsp. enterica Typhimurium and Salmonella enterica subsp. enterica Derby were detected in same or different seafood throughout the study period. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the microbiological quality of farmed giant freshwater prawn (Macrobrachium rosenbergii) collected from four freshwater farms located in Kerala (India). Microbiological counts on whole, deheaded, and deheaded and deveined prawn as well as on head and intestine were determined. Average counts (log10 cfu g-¹) on whole prawn were 6.9 (total mesophilic counts (TPC) at 37°C) and 4.1 (psychrotrophic count at 7°C). The results indicated that the aerobic counts were within the acceptable limit. The levels of enterococci and faecal coliforms in farmed M. rosenbergii were high. There was an increase in the numbers of enterococci and Staphylo- coccus aureus after deheading. The major groups of bacteria comprising the flora of M. rosenbergii were Aeromonadaceae, Enterobacteriaceae and Pseudo,nonas. Farmed M. rosenbergii carried pathogenic bacteria such as Enterococcus spp., S. aureus, Aeromonas hydrophila, A. veronii biovar sobria and Clostridium perfringens. The results of the study sug- gest adoption of good farming and post harvest practices to improve the microbiological quality of farmed freshwater prawn. [Article copies available [ABSTRACT FROM AUTHOR]

Escherichia coli is a common contaminant of seafood in the tropics and is often encountered in high numbers. The count of E. coil as well as verotoxigenic E. coli O157:H7 was estimated in 414 finfish samples composed of 23 species of fresh fish from retail markets and frozen fish from cold storage outlets in and around Cochin, India. A total of 484 presumptive E. coli were isolated, and their indole-methyl red-Voges-Proskauer-citrate (IMViC) pattern was determined. These strains were also tested for labile toxin production by a reverse passive latex agglutination method and checked for E. coli serotype O157 by latex agglutination with O157-specific antisera. Certain biochemical marker tests, such as methylumbelliferyl-β-glucuronide (MUG), sorbitol fermentation, decarboxylase reactions, and hemolysis, which are useful for screening pathogenic E. coli, were also carried out. Results showed that 81.4% of the E. coli isolates were sorbitol positive. Among this group, 82% were MUG positive, and 14.46% of the total E. coli isolates showed human blood hemolysis. None of the isolates were positive for agglutination with E. coli O157 antisera nor did any produce heat-labile enterotoxin. This study indicates that typical E. coli O157 or labile toxin-producing E. coli is absent in the fish and fishery environments of Cochin (India). However, the presence of MUG and sorbitol-negative strains that are also hemolytic indicates the existence of aberrant strains, which require further investigation. [ABSTRACT FROM AUTHOR]

A 63-year-old male presented with sudden increase in size of a right inguinal swelling which was present for the past 10 years. Clinical diagnosis of inguinal soft tissue mass/lymph node enlargement was made and patient was investigated further for a conclusive diagnosis. Ultrasound examination suggested it to be a lymph node and guided fine needle aspiration cytology was performed. Cytology was suggestive of a reactive lymph node. Subsequently, an excision biopsy was performed that revealed a granular cell tumor with many lymphoid aggregates. On reviewing the cytosmears, we realised that the granular neoplastic cells were mistaken for histiocytes; and the lymphoid background and bare nuclei mislead us to consider it a reactive lymph node. Since granular cell tumor can occur almost anywhere, a careful examination of cytosmears and knowledge of its distinctive cyto-morphological features would be helpful in providing an accurate diagnosis on cytology. [ABSTRACT FROM AUTHOR]

A novel ultra-wideband short range radar (UWB-SRR) system for measuring a target maximum range of 15 m and relative velocity of 150 km/h is proposed. The conventional detector has less detection performance if the reflected echo signals from the target are more distributed because the detection performance depends on a particular range bin only. However, the proposed detector's detection performance is increased when the reflected echo signals from the target are combined using the proposed sliding window. According to the presented simulation and theoretical analysis, the proposed detector is superior to conventional detectors when the target echo signal is more distributed against a background of additive white Gaussian noise. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 19-year-old male who complained of hair in the oral cavity since 2 months. He had a slow growing mass in the mandible for the past 7 years. A biopsy was conducted on the patient and he was later diagnosed with ameloblastoma. He later complained of hair growth in the grafted site after the surgery. It notes that ameloblastoma is one of the most common odontogenic tumors, which accounts for only 1% of all oral tumors.

The short story "Akamveedu," (Indoors) by P. Surendran is presented.

The short story "Puramveedu," (Outdoors), by P. Surendran is presented.