Photosensitive activity of fabricated core-shell composite nanostructured p-CuO@CuS/n-Si diode for photodetection applications.

Development of photo detectors based on different semiconducting materials with high performance has been in progress in recent past, however, there is a lot of difficulties in developing the more effective photo detectors-based devices with high responsivity, detectivity and quantum efficiency. Hence, we have synthesized pure CuS and CuO@CuS core-shell heterostructure based photo detectors with high performance by simple and cost-effective two-step chemical co-precipitation method. The phase purity of CuS and CuO@CuS composite was observed by XRD analysis and the result were verified with Raman spectroscopy studies. Sphere like morphology of pure CuS and core-shell structure formation of CuO@CuS are observed with scanning and transmission electron microscopes. The presence of expected elements has been confirmed with EDX elemental mapping. Light harvesting photodiodes were fabricated by using n-type silicon substrate through drop cost method. Photo sensitive parameters of fabricated diodes were analyzed by I-V characteristics. The p-CuO@CuS (1:1)/n-Si diode owned a maximum photosensitivity (Ps) ∼ 7.76 × 104 %, photoresponsivity (R) ∼ 798.61 mA/W, external quantum efficiency ( E Q E )∼309.66 % and specific detectivity (D*) ∼ 8.19 × 1011 Jones when compared to p-CuS/n-Si diode. The obtained results revealed that the core/shell heterostructure of CuO@CuS is the most appropriate for photo detection.

Rare Earth Element (REE) Nd3+ Doped CeO2 Nanoparticles Using Aloe vera Leaf Extract: Structural, Optical and Antimicrobial Activity.

Pure and Nd-doped cerium oxides (CeO2, Ce0.075Nd0.025O and Ce0.050Nd0.050O) nanoparticles (NPs) were synthesized using Aloe vera leaf extract. X-ray powder diffraction studies were confirmed that synthesized pure and Nd3+ doped CeO2 NPs and were exhibited cubic structure. FE-SEM image exhibited pure and Nd3+ doped CeO2 NPs have spherical structure and Nd doped CeO2 NPs small pores were formed in the surface. EDAX spectral analysis used to identify the elemental compositions. FT-IR spectra shows various functional groups and were identified for pure and Nd3+ doped CeO2 NPs. UV-Vis spectra, absorption edges were observed at 314 nm, 324 nm and 357 nm for pure and Nd doped CeO2 NPs respectively. PL spectral analysis, small shift observed for emission of the CeO2 NPs values as compared to that of the Nd doped CeO2 NPs emission values. The antimicrobial studies were performed against a set of Gram positive (Staphylococcus aureus and Streptococcus pneumoniae) and Gram negative (Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella pneumonia and Shigella dysenteriae) bacterial and fungal candida albicans strain.

4-Nitro-phenol-2,4,6-triamino-1,3,5-triazine-water (2/1/1).

In the title adduct, 2C(6)H(5)NO(3)·C(3)H(6)N(6)·H(2)O, the melamine and the two independent nitrophenol molecules are essentially planar, with maximum deviations of 0.0294 (10), 0.0706 (12) and 0.0742 (12) Å, respectively. In the crystal, N-H⋯N, O-H⋯N, N-H⋯O and O-H⋯O hydrogen bonds link the components into a three-dimensional network. In addition, weak π-π inter-actions [centroid-centroid distances = 3.728 (3) and 3.749 (3) Å] are observed.

Diode laser for paediatric airway procedures: a useful tool.

OBJECTIVE: A wide range of lasers have been used in the larynx. Diode laser is a portable and relatively inexpensive laser which is delivered via a glass fibre hand-held probe. The objective of this study was to report our experience with the use of diode laser in a variety of paediatric airway pathologies. METHODS: In this study, 90 diode laser laryngeal procedures were performed on 31 patients in the age range of 1 month to 16 years at the time of the operation. The follow up after the procedure has been in the range of 6 months to 3 years. RESULTS: As per our records 19/31 (61.3%) patients have been cured of their initial pathologies and were not under further review, 3/31 (9.6%) were having repeated laser treatments. The remaining 9/31 (29.0%) had to undergo further treatment. There was no laser-related intra-operative or postoperative complications. CONCLUSIONS: Diode laser is a good tool for several paediatric laryngeal pathologies. The ability to guide the laser light using the flexible glass fibre directly onto the area requiring vapourisation enables very precise treatment.

Spectroscopic and structural investigations on modafinil by FT-IR, FT-Raman, NMR, UV-Vis and DFT methods.

Chiral sulfoxide based smart drug modafinil were studied experimentally and theoretically. Vibrational spectra were recorded in the mid IR region and electronic spectra were recorded in UV-Visible region. The molecular geometry, vibrational spectra, magnetic spectra and electronic spectra were simulated using Density Functional Theory (DFT) employed with B3LYP/6-311++G(d,p) basis set. The molecular geometry optimization, vibrational frequencies, chemical shifts and solvent effect on electronic properties were reported. The intermolecular interactions have been studied by Hirshfeld surface analysis. There is good agreement was found between calculated and observed values, thereby to confirm the molecular structure of modafinil.

Prolonged persistence of residual Wuchereria bancrofti infection after cessation of diethylcarbamazine-fortified salt programme.

A diethylcarbamazine (DEC)-fortified salt intervention programme was implemented between 1982 and 1986 in Karaikal district, Union territory of Pondicherry, south India, to control Culex transmitted bancroftian filariasis. The intervention reduced the microfilaria (Mf) rate from 4.49% to 0.08%. To eliminate the residual microfilaraemia, the health department detected and treated Mf carriers from 1987 to 2005 and mass-administered drugs in 2004 and 2005. Surveillance from 1987 to 2005 revealed persistent microfilaraemia in 0.03-0.42% of the population. In 2006, we conducted a more detailed Mf survey and a child antigenaemia (Ag) survey in 15 urban wards and 17 rural villages. These surveys showed an overall Mf rate of 0.46% in the high-risk urban areas and 0.18% in the rural areas; none of the sampled children was positive for Ag. All detected Mf carriers were >20 years old. The age of the youngest Mf carrier was 30 years in urban and 21 years in rural areas, which suggests that transmission was interrupted and there was no incidence of new Mf case after cessation of DEC salt programme. Eleven of 15 urban and 15 of 17 villages were totally free from microfilaraemia. Nevertheless, three of 15 surveyed urban localities and two of 17 villages showed >1% Mf rate. Thus, it seems that (i) post-intervention very low levels of microfilaraemia can continue as long as 20 years; (ii) 0.60-0.70% Mf rate is a safe level and at this level recrudescence of infection may not occur; (iii) there can be isolated localities with >1% Mf rate and their detection for further intervention measures could be challenging in larger control/elimination programmes and (iv) the residual infection mostly gets concentrated in the adult population, in underdeveloped urban areas and in historically highly endemic or large endemic rural areas. These groups and areas should be targeted with rigorous intervention measures such as mass drug administration to eliminate the residual infection.

Long-term results with a simple technique of stoma creation after laryngectomy.

Stomal stenosis after laryngectomy has a major impact on patient rehabilitation. The major contributory factor is the operative technique. The goal is to achieve a widely patent stoma. The objective of the study was to review the long-term results of the technique of stoma creation used by the senior author (CJW). The simple technique, using skin triangles for tracheostoma creation after laryngectomy, has been used by the senior author for past 6 years. Review of 59 cases of total laryngectomy with or without partial pharyngectomies in whom this technique was used for stomaplasty. The technique described for stoma creation after total laryngectomy has been used in 59 patients (48 male, 11 female) over 6 years. The follow-up of these patients varies from 6 months to 6 years. Of these patients 54/59 (91.5%) did not have any problems with the stoma. A total of 5/59 (8.5%) patients, the stoma was narrow. Amongst these patients with narrow stoma, only 1 patient (1.7%) has had dilatation done and the others are managing reasonably with a stoma button. None of the patients in this study has required revision procedures on the stoma. The simple technique of stoma creation described in this study has good long-term results.

Chitosan-capped gold nanoparticles for indicating temperature abuse in frozen stored products.

The present study aimed to optimize the conditions for the synthesis of gold nanoparticles (AuNP) using chitosan and to assess its effectiveness as temperature threshold indication for frozen storage conditions. Chitosan concentration of 0.25% and temperature of 90 °C for 15 min was optimum for synthesizing AuNP. The maximum absorbance (λ max) was observed at 530 and 540 nm for 0.125% and 0.25% chitosan, respectively, indicating shifting of peak toward longer wavelengths (red shift) with increasing chitosan concentration indicating larger AuNPs. A prominent absorption peak at 1367 cm-1 by Fourier transform-infrared (FTIR) spectrum corresponding to C-C stretching of the glucosamine group of chitosan indicates the chitosan capping on the AuNP. Higher peak intensity and a peak shift toward shorter wavelength were observed for AuNPs exposed to frozen temperature abused conditions. Distinctly clear visible color variation from cherry red to gray indicates its application as temperature abuse indicator in frozen products.

Optical absorption and EPR studies on some natural carbonate minerals.

Limestone and dolomite minerals have been investigated by EPR and optical absorption studies. The optical absorption results indicate the presence of ferrous and ferric ion in both the minerals. The bands observed at 24,750, 22,780, 19,415 and 14,450cm(-1) are assigned to 6A1-->4T2 (4D), 6A1-->4E, 4A1 (4G), 6A1-->4T2 (4G) and 6A1-->4T1 (4G) d-d transitions of Fe3+ ions, respectively. A low energy band at 10,638cm(-1) is identified as being due to Fe2+ ion and can be attributed to 5T2g-->5E(g) transition. The weak band in the region 30,000-40,000cm(-1) corresponds to Fe-O charge transfer. Crystal field and Racah parameters evaluated for the Fe2+ ion are Dq=990cm(-1), B=885cm(-1) and C=3860cm(-1) and that for Fe3+ ions are Dq=1040cm(-1), B=703cm(-1) and C=3150cm(-1). The room temperature 9 and 35GHz EPR spectra of the minerals exhibit a sextet hyperfine pattern characteristic of Mn2+. The EPR parameters obtained for Mn2+ in limestone are g=2.00399, A= -9.411mT, D= -8.19mT and these values confirm that the Mn2+ ion are located in the calcite impurity. For Mn2+ in dolomite are g=2.0004, A= -9.45mT for Mn2+ substituted in the Ca lattice site and g=2.00984, A= -9.37mT, D= -9.94mT for substitution at the Mg site. The EPR spectra of heat-treated limestone and dolomite samples at 950 degrees C show a signal corresponding to CO2(-) ion.

Spectroscopic study of phase transitions in natural calcite mineral.

The process and the formation of new minerals upon heating the carbonate rocks containing clay minerals, together with calcite are determined with thermal analysis, X-ray diffraction, infrared and Raman spectroscopy. The calcite-calcium oxide phase transition sequence was followed up to 947 degrees C in naturally occurring limestone samples. The spectral variations of the internal modes of the carbonate trigonal (nu(1), nu(2), nu(3) and nu(4)) were used to probe the structural phase transitions. The calcium oxide phase (which on reaction with atmospheric water forms portlandite) with an onset temperature of around 950 degrees C was also characterized by the appearance of the infrared mode around 450 cm(-1). The minerals, which were formed upon heating the calcite, were calcium oxide and wollastonite.

Vibrational spectroscopy investigation using ab initio and density functional theory on p-anisaldehyde.

The FTIR and FT Raman spectra of p-anisaldehyde has been recorded in the regions 4,000-400 and 3,500-100 cm(-1), respectively. The optimized geometry, frequency and intensity of the vibrational bands of p-anisaldehyde were obtained by ab initio and DFT levels of theory with complete relaxation in the potential energy surface using 6-31G(d,p) basis set. A complete vibrational assignment aided by the theoretical harmonic frequency analysis has been proposed. The harmonic vibrational frequencies calculated have been compared with experimental FTIR and FT Raman spectra. The observed and the calculated frequencies are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically constructed bar type spectrograms.

A novel spectroscopic analysis to detect photochemical reaction of the bronchodilator - Doxofylline and its estimation in pharmaceutical formulation.

Photostability studies of drugs and drug products are an integral part of the product development process in the pharmaceutical industry. These studies are carried out to ensure quality, efficacy and safety of the formulated products during manufacture, storage and use. In this investigation, a novel spectroscopic approach has been adopted by employing the FTIR-ATR and UV/Visible techniques to detect the photochemical reactions of the drug Doxofylline, chemically designated as 7-(1, 3 dioxolane-2-yl methyl) theophylline, in its raw (pure) form. Significant changes were observed in terms of optical density of the absorption bands and a satisfactory analysis has been performed using ANOVA Statistics. It highlights the role of the photochemistry of drugs with respect to its spectral profiles and also explains photo physical processes. In addition; the drug compatibility study was also undertaken by using FTIR-ATR technique which indicated that there were no interactions occurring between the raw sample of the drug and the excipients used in the preparation of the pharmaceutical formulation. With this, UV-visible spectroscopic method was validated for the quantitative estimation of Doxofylline in pharmaceutical dosage forms and was performed with λmax at 274nm. Calibration curves were linear between the concentration range 10-50µg/ml. The various parameters such as linearity, precision, accuracy, recovery and specificity were studied according to ICH guidelines (Ahmed et al., 2016; Jain et al., 2011; ICH, 1996).

Spectroscopic characterization of natural calcite minerals.

The FT-IR, FT-Raman, NMR spectral data of ten different limestone samples have been compared. FT-IR and FT-Raman spectral data show that calcium carbonate in limestone, principally in the form of calcite, as identified by its main absorption bands at 1426, 1092, 876 and 712 cm(-1). The sharp diffractions at the d-spacings, 3.0348, 1.9166 and 1.8796 confirm the presence of calcite structure and the calculated lattice parameters are: a=4.9781 A, c=17.1188 A. The range of 13C chemical shifts for different limestone samples is very small, varying from 198.38 to 198.42 ppm. The observed chemical shifts are consistent with the identical C-O bonding in different limestone samples. 27Al MAS NMR spectra of the samples exhibit a central line at 1 ppm and another line at 60 ppm corresponding to octahedral and tetrahedral Al ions, respectively. The five component resonances were observed in 29Si MAS NMR spectrum of limestone and these resonances were assigned to Si (4 Al), Si (3 Al), Si (2 Al), Si (1 Al) and Si (0 Al) from low field to high field.

FTIR spectra and mechanical strength analysis of some selected rubber derivatives.

Rubber materials have wide range of commercial applications such as, infant diapers, famine hygiene products, drug delivery devices and incontinency products such as rubber tubes, tyres, etc. In the present work, studies on mechanical properties of some selected rubber materials viz., natural rubber (NR), styrene butadiene rubber (SBR), nitrile butadiene rubber (NBR) and ethylene propylene diene monomer (EPDM) have been carried out in three states viz., raw, vulcanized and reinforced. To enhance the quality of rubber elastomers, an attempt is made to prepare new elastomers called polyblends. In the present study an attempt is made to blend NR with NBR and with EPDM. We here report, a novel approach for the evaluation of various physico-mechanical properties such as mechanical strength, tensile strength, elongation and hardness. The method is simple, direct and fast and involves infrared spectral measurements for the evaluation of these properties. With the applications of modern infrared spectroscopy, the mechanical strength of these rubber materials have been analyzed by calculating the internal standards among the methyl and methylene group vibrational frequencies obtained from FTIR spectroscopy. Also the tensile strength measurements carried out by universal testing machine. The results pertaining physico-mechanical properties of the rubber derivatives undertaken in the present study obtained by IR-based method are in good agreement with data resulted from the standard methods.

Sporulation and regeneration efficiency of phosphobacteria (Bacillus megaterium var phosphaticum).

Sporulation in Bacillus megaterium var phosphaticum (PB - 1) was induced using modified nutrient media. This modified medium induced sporulation within 36 h. After spore induction the spores were kept under refrigerated (5°C) and room temperature (32°C) for five months and survival of spores was studied at 15 days intervals by plating them in nutrient agar medium. It was observed that there was not much variation in the storage temperature (5°C & 32°C). The spore cells of Bacillus megaterium var phosphaticum (PB - 1) were observed up to five months of storage under refrigerated (5°C) and room temperature (32°C). Regeneration of spore cells into vegetative cells was studied in tap water, rice gruel, nutrient broth, sterile lignite and sterile water at different concentrations of spore inoculum. The multiplication of sporulated Bacillus megaterium var phosphaticum culture was fast and reached its maximum (29.5 × 10(8) cfu ml(-1)) in nutrient broth containing 5 per cent inoculum level.

Improvement of Insulin Secretion and Pancreatic ß-cell Function in Streptozotocin-induced Diabetic Rats Treated with Aloe vera Extract.

BACKGROUND: Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia. Plant extracts and their products are being used as an alternative system of medicine for the treatment of diabetes. Aloe vera has been traditionally used to treat several diseases and it exhibits antioxidant, anti-inflammatory, and wound-healing effects. Streptozotocin (STZ)-induced Wistar diabetic rats were used in this study to understand the potential protective effect of A. vera extract on the pancreatic islets. OBJECTIVE: The aim of the present study was to evaluate the A. vera extract on improvement of insulin secretion and pancreatic ß-cell function by morphometric analysis of pancreatic islets in STZ-induced diabetic Wistar rats. MATERIALS AND METHODS: After acclimatization, male Wistar rats, maintained as per the Committee for the Purpose of Control and Supervision of Experiments on Animals guidelines, were randomly divided into four groups of six rats each. Fasting plasma glucose and insulin levels were assessed. The effect of A. vera extract in STZ-induced diabetic rats on the pancreatic islets by morphometric analysis was evaluated. RESULTS: Oral administration of A. vera extract (300 mg/kg) daily to diabetic rats for 3 weeks showed restoration of blood glucose levels to normal levels with a concomitant increase in insulin levels upon feeding with A. vera extract in STZ-induced diabetic rats. Morphometric analysis of pancreatic sections revealed quantitative and qualitative gain in terms of number, diameter, volume, and area of the pancreatic islets of diabetic rats treated with A. vera extract when compared to the untreated diabetic rats. CONCLUSION: A. vera extract exerts antidiabetic effects by improving insulin secretion and pancreatic ß-cell function by restoring pancreatic islet mass in STZ-induced diabetic Wistar rats. SUMMARY: Fasting plasma glucose (FPG) and insulin levels were restored to normal levels in diabetic rats treated with Aloe vera extractIslets of pancreas were qualitatively and quantitatively restored to normalcy leading to restoration of FPG and insulin levels of diabetic rats treated with Aloe vera extractMorphometric analysis of pancreatic sections revealed quantitative and qualitative gain in terms of number, diameter, volume, and area of the pancreatic islets of diabetic rats treated with Aloe vera extract when compared to the untreated diabetic rats. Abbreviations Used:A. vera, FPG: Fasting plasma glucose, STZ: Streptozotocin, BW: Body weight.

Stenting for bilateral congenital choanal atresia--a new technique.

We describe a new nasal stent for the treatment of bilateral congenital choanal atresia. The stent is made up of reinforced endotracheal tube mounted on a portex carrier tube. It potentially causes less internal crusting and stent blockage and is secured without sutures. It remains patent for at least 4 weeks. We have used the stent successfully in six patients between 1998 and 2004 at Leeds General Infirmary and present the data collected retrospectively. The current practice in the UK for treatment and stenting for congenital choanal atresia was investigated by a prospective internet based questionnaire sent to 18 consultant paediatric otolaryngologists of whom 12 (67%) responded. Their experience and results are reported. The literature has been reviewed.

Vibrational spectra and normal coordinate analysis of diazepam, phenytoin and phenobarbitone.

Vibrational spectroscopy is an important tool for the structural investigation of the organic molecules. In the present investigation, a normal coordinate analysis has been carried out on some anti-epileptic drugs, viz. diazepam, phenytoin and phenobarbitone. Diazepam is a derivative of benzodiazepine, phenytoin is a derivative of hydanation and pheonobarbitone is a barbiturate. The infrared spectra of the compounds are recorded in the region 4000-400 cm(-1) and Raman spectra are recorded in the region 3500-50 cm(-1). From the structural point of view, diazepam, phenytoin and phenobarbitone have been assumed to C(s) point group. A systematic set of symmetry coordinates has been constructed for these compounds and Wilson's FG matrix method has been applied for the normal coordinate analysis using general quadratic valance force field. The potential energy distribution is also calculated to check the vibrational band assignments.

Experimental and theoretical study of ornidazole.

The Fourier transform infrared (FT-IR) and the Fourier transform Raman (FT-Raman) spectra of the title molecule in solid phase were recorded in the region 4000-400 cm(-1) and 4000-100 cm(-1) respectively. The geometrical parameters and energies were investigated with the help of Density Functional Theory (DFT) employing B3LYP method and 6-31G (d, p) basis set. The analysis was supported by electrostatic potential maps and calculation of HOMO-LUMO. UV, FT-IR and FT-Raman spectra of ornidazole were calculated and compared with experimental results. Thermodynamic properties like entropy, heat capacity, have been calculated for the molecule. The predicted first hyperpolarizability also shows that the molecule might have a reasonably good non-linear optical (NLO) behavior. The intramolecular contacts have been interpreted using natural bond orbital (NBO) and natural localized molecular orbital (NLMO) analysis.

DNA Repair Gene (XRCC1) Polymorphism (Arg399Gln) Associated with Schizophrenia in South Indian Population: A Genotypic and Molecular Dynamics Study.

This paper depicts the first report from an Indian population on the association between the variant Arg399Gln of XRCC1 locus in the DNA repair system and schizophrenia, the debilitating disease that affects 1% of the world population. Genotypic analysis of a total of 523 subjects (260 patients and 263 controls) revealed an overwhelming presence of Gln399Gln in the case subjects against the controls (P < 0.0068), indicating significant level of association of this nsSNP with schizophrenia; the Gln399 allele frequency was also perceptibly more in cases than in controls (p < 0.003; OR = 1.448). The results of the genotypic studies were further validated using pathogenicity and stability prediction analysis employing computational tools [I-Mutant Suite, iStable, PolyPhen2, SNAP, and PROVEAN], with a view toassess the magnitude of deleteriousness of the mutation. The pathogenicity analysis reveals that the nsSNP could be deleterious inasmuch as it could affect the functionality of the gene, and interfere with protein function. Molecular dynamics simulation of 60ns was performed using GROMACS to analyse structural change due to a mutation (Arg399Gln) that was never examined before. RMSD, RMSF, hydrogen bonds, radius of gyration and SASA analysis showedthe existence of asignificant difference between the native and the mutant protein. The present study gives astrong indication that the XRCC1 locus deserves serious attention, as it could be a potential candidatecontributing to the etio-pathogenesis of the disease.