Effect of Mn²⁺ concentration in ZnS nanoparticles on photoluminescence and electron-spin- resonance spectra

Organically capped zinc sulfide nanoparticles doped with different manganese concentrations were prepared under similar conditions. Only the doping concentration was varied. Photoluminescence and electron-spin-resonance (ESR) investigations show some new results. At an optimum concentration of Mn doping a maximum in the photoluminescence is reached, whereas photoluminescence quenching occurs at higher concentrations. ESR investigations show that the spectra arise due to four different contributions of Mn ions, viz., (1) Mn(SI) in tetrahedral cationic substitution site with Td symmetry, (2) isolated Mn ions at the surface or interstitial locations (SII) with octahedral symmetry (Oh), (3) Mn-Mn dipolar interactions (SIII), and (4) exchange-coupled Mn clusters (SIV) in various proportions. Linewidths for all these (SI–SIV) differ from each other. Identification of these components suggests that SI may be responsible for the photoluminescence increase, whereas SII–SIV may be responsible for the luminescence quenching in nanoparticles

FORMULATION AND EVALUATION OF MOUTH DISSOLVING TABLET OF AMLODIPINE BESYLATE

Objective: The main objective of this research work was to formulate and evaluate the mouth dissolving tablet of amlodipine besylate for the treatment of hypertension and coronary artery disease. Methods: In this study, mouth dissolving tablet were prepared by direct compression method by using croscarmellose sodium and sodium starch glycolate as superdisintegrants. The designed tablets were subjected to various assessment parameters like friability test, hardness test, disintegration test, wetting time, in vitro drug release and drug content. Results: All the prepared formulations were subjected to various assessment parameters, and the findings obtain within the prescribed limit. The calibration curve of pure drug using various solvents like phosphate buffer pH 6.8, methanol was plotted. F1-F9 containing croscarmellose sodium and sodium starch glycolate in various concentration demonstrate the minimum disintegration time. Among all these formulations F9 shows disintegration time up to 22±1.12 seconds due to the high concentration of superdisintegrants. In vitro drug release was tested in phosphate buffer pH 6.8 at a time interval of 0, 1, 2, 3, 4, 5 min. The F9 shows drug release 100.22±1.08%. Accelerated stability study of optimized formulation (F9) up to 2 mo showed there was no change in disintegration time and percentage drug release. Conclusion: The results obtained in the research work clearly showed a promising potential of mouth dissolving tablets containing a specific ratio of croscarmellose sodium and sodium starch glycolate as superdisintegrants for the effective treatment of hypertension and coronary artery disease

Difference in electronic structure between tetragonal and cubic SrNbO2N

We report here a comparative study of the electronic structure of earlier known cubic phase and the recently, reported correct tetragonal phase of SrNbO2N. We performed the calculations within the framework of density-functional theory (DFT) by using the WIEN97 code. The valence band consists of N 2p while the conduction band consists of Nb 4d in cubic system; on the contrary, these Nb 4d states show a strong interaction with anion p states in tetragonal system and indicate theoretically, a metallic behavior. The direct forbidden gap of tetragonal system was 0 eV, whereas for cubic system was 0.2 eV; the relative difference in the band gap of two systems is possibly attributed to the high covalency and is possibly acquired due to the presence of the shorter bond length of Nb - N than that of Nb-O in the tetragonal system. The results of electronic structures have been discussed in the light of optical applications of this oxynitride in solar energy conversion. The calculated optical-absorption coefficient I(w) from real and imaginary parts of dielectric function, further clarifies the suitability of the application. (c) 2005 American Institute of Physicsclose5

Retrospective analysis of necropsy findings in patients of H1N1 and their correlation to clinical features

India reported its first case of H1N1 in July 2009 in Pune and since then, the number of reported cases and deaths exploded in India. Since very little data is available about histopathological findings in patients of H1N1 fatal cases in India, a retrospective chart analysis of necropsy findings of 15 cases of 2009 H1N1 fatal cases was performed. Common clinical features were fever, cough , and breathlessness followed by sore throat and rhinorrhea. Common lung findings were mononuclear cell infiltration, thick alveolar septae, intraalveolar hemorrhage . The other findings were congested pulmonary blood vessels, pulmonary edema, cytomegaly, fibrin accumulation and formation of eosinophilic membrane. These findings are suggestive of diffuse alveolar damage ( DAD) and DAD with hemorrhage. All patients who underwent necropsy had radiographic findings suggestive of unilobar or multilobar pneumonia. This clinical finding can be correlated pathologically in these patients as all of them had either polymorphonuclear or mononuclear infiltrate. Furthermore, necrotizing pneumonitis pattern seen on these patients is the likely cause of mortality in these patients. Although clinical ARDS pattern was noted in all these patients, it was well correlated in lung pathology in all these cases

Novel extractant impregnated resin for preconcentration and determination of uranium from environmental samples

A novel method based on impregnation of Amberlite XAD-4 with extractant isonitroso-4-methyl-2-pentanone (IMP) has been developed for U6 + extraction and determination in various samples. The prepared extractant im- pregnated resin (EIR) sorbent was characterized by the field emission scanning electron microscope. The sorbent was packed in a glass column and investigated for various parameters such as pH, eluent, sample and eluent flow rates to optimize sorption desorption conditions for U6+. U6+ is quantitatively determined at pH 4 with flow rate 2 mL/min which showed recovery of 98.9%. The sorption behaviour of U6 + by EIR was also studied using different equilibrium isotherms and kinetic models and the experimental data confirmed that it follows Freundlich iso- therm and Weber-Morris pore diffusion kinetic model. The investigation of foreign ions influence on U6+ sorp- tion showed least interference and thus, facilitated its extraction and determination in Uranmicrolite (leachate) ore tailing, synthetic mixtures and spiked water samples. The detection limit was 0.41 μg/L while the limit of quantification as 1.35 μg/L made the method quite accurate

Bio-nanotechnology application in wastewater treatment

The nanoparticles have received high interest in the field of medicine and water purification, however, the nanomaterials produced by chemical and physical methods are considered hazardous, expensive, and leave behind harmful substances to the environment. This chapter aimed to focus on green-synthesized nanoparticles and their medical applications. Moreover, the chapter highlighted the applicability of the metallic nanoparticles (MNPs) in the inactivation of microbial cells due to their high surface and small particle size. Modifying nanomaterials produced by green-methods is safe, inexpensive, and easy. Therefore, the control and modification of nanoparticles and their properties were also discussed

Pleosporales

One hundred and five generic types of Pleosporales are described and illustrated. A brief introduction and detailed history with short notes on morphology, molecular phylogeny as well as a general conclusion of each genus are provided. For those genera where the type or a representative specimen is unavailable, a brief note is given. Altogether 174 genera of Pleosporales are treated. Phaeotrichaceae as well as Kriegeriella, Zeuctomorpha and Muroia are excluded from Pleosporales. Based on the multigene phylogenetic analysis, the suborder Massarineae is emended to accommodate five families, viz. Lentitheciaceae, Massarinaceae, Montagnulaceae, Morosphaeriaceae and Trematosphaeriaceae

A step forward for understanding the morbidity burden in Guinea: a national descriptive study

<p>Abstract</p> <p>Background</p> <p>Little evidence on the burden of disease has been reported about Guinea. This study was conducted to demonstrate the morbidity burden in Guinea and provide basic evidence for setting health priorities.</p> <p>Methods</p> <p>A retrospective descriptive study was designed to present the morbidity burden of Guinea. Morbidity data were extracted from the National Health Statistics Report of Guinea of 2008. The data are collected based on a pyramid of facilities which includes two national hospitals (teaching hospitals), seven regional hospitals, 26 prefectural hospitals, 8 communal medical centers, 390 health centers, and 628 health posts. Morbidity rates were calculated to measure the burden of non-fatal diseases. The contributions of the 10 leading diseases were presented by sex and age group.</p> <p>Results</p> <p>In 2008, a total of 3,936,599 cases occurred. The morbidity rate for males was higher than for females, 461 versus 332 per 1,000 population. Malaria, respiratory infections, diarrheal diseases, helminthiases, and malnutrition ranked in the first 5 places and accounted for 74% of the total burden, respectively having a rate of 148, 64, 33, 32, and 14 per 1,000 population. The elderly aged 65+ had the highest morbidity rate (611 per 1,000 population) followed by working-age population (458 per 1,000 population) and children (396 per 1,000 population) while the working-age population aged 25-64 contributed the largest part (39%) to total cases. The sex- and age-specific spectrum of morbidity burden showed a similar profile except for small variations.</p> <p>Conclusion</p> <p>Guinea has its unique morbidity burden. The ten leading causes of morbidity burden, especially for malaria, respiratory infections, diarrheal diseases, helminthiases, and malnutrition, need to be prioritized in Guinea.</p