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Search Results: 1 - 10 of 487181 matches for " S. R. Saha "
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Soil Health Management under Hill Agroecosystem of North East India
R. Saha,R. S. Chaudhary,J. Somasundaram
Applied and Environmental Soil Science , 2012, DOI: 10.1155/2012/696174
Abstract: The deterioration of soil quality/health is the combined result of soil fertility, biological degradation (decline of organic matter, biomass C, decrease in activity and diversity of soil fauna), increase in erodibility, acidity, and salinity, and exposure of compact subsoil of poor physicochemical properties. Northeast India is characterized by high soil acidity/Al+3 toxicity, heavy soil, and carbon loss, severe water scarcity during most parts of year though it is known as high rainfall area. The extent of soil and nutrient transfer, causing environmental degradation in North eastern India, has been estimated to be about 601 million tones of soil, and 685.8, 99.8, 511.1, 22.6, 14.0, 57.1, and 43.0 thousand tones of N, P, K, Mn, Zn, Ca, and Mg, respectively. Excessive deforestation coupled with shifting cultivation practices have resulted in tremendous soil loss (200?t/ha/yr), poor soil physical health in this region. Studies on soil erodibility characteristics under various land use systems in Northeastern Hill (NEH) Region depicted that shifting cultivation had the highest erosion ratio (12.46) and soil loss (30.2–170.2?t/ha/yr), followed by conventional agriculture system (10.42 and 5.10–68.20?t/ha/yr, resp.). The challenge before us is to maintain equilibrium between resources and their use to have a stable ecosystem. Agroforestry systems like agri-horti-silvi-pastoral system performed better over shifting cultivation in terms of improvement in soil organic carbon; SOC (44.8%), mean weight diameter; MWD (29.4%), dispersion ratio (52.9%), soil loss (99.3%), soil erosion ratio (45.9%), and in-situ soil moisture conservation (20.6%) under the high rainfall, moderate to steep slopes, and shallow soil depth conditions. Multipurpose trees (MPTs) also played an important role on soil rejuvenation. Michelia oblonga is reported to be a better choice as bioameliorant for these soils as continuous leaf litter and root exudates improved soil physical behaviour and SOC considerably. Considering the present level of resource degradation, some resource conservation techniques like zero tillage/minimum tillage, hedge crop, mulching, cover crop need due attention for building up of organic matter status for sustaining soil health. 1. Introduction Soil degradation has raised some serious debate, and it is an important issue in the modern era. It refers to the decline in soil’s inherent capacity to produce economic goods and perform ecologic functions. It is the net result of dynamic soil degradative and restorative processes regulated by natural and anthropogenic
Enteric pathogens in north Indian patients with diarrhoea
Das S,Saha R,Singhal S
Indian Journal of Community Medicine , 2007,
Abstract: Background : Diarrhoeal diseases are a leading cause of morbidity and mortality among children in developing countries requiring hospitalisation. AIDS and indiscriminate use of antibiotics have further worsen the condition. Objectives : To assess the etiological agents causing diarrhea with the aim to limit indiscriminate use of antimicrobial agents. Methods : A cross-sectional study was done involving children and adults (of all age groups) suffering from gastrointestinal infection attending the OPD or admitted to Guru Teg Bahadur Hospital. The study was analysed using chi-square test and crosstab chi-square test. Results : Of the 2534 stool samples processed, 23.2% were positive for pathogens. 4.6% were positive for Shigella species, 2.37% for Salmonella species and 1.5% for Escherichia coli (E.coli). Vibrio cholerae OI El Tor serotype Ogawa (82.55%) was more common than serotype Inaba (19.5%). Vibrio cholerae strains were generally resistant to all drugs except Ciprofloxacin, Gentamicin, and Cefotaxime. Multidrug resistant Shigella and Salmonella species was also an important observation made. However parasitic and viral (rota virus) associated diarrhea did not exceed the bacterial causes. Conclusions : New pathogens have emerged as causative organisms of diarrhoa. Indiscriminate use of antibiotics can lead to drug resistance necessitating monitoring of drug susceptibility and formulation of drug policy in hospitals.
Disseminated nodular granulomatous perifolliculitis
Das S,Saha R,Bhattacharya S
Indian Journal of Medical Microbiology , 2007,
Abstract: Nodular granulomatous perifolliculitis is a well-recognized infection of the dermal and subcutaneous tissue caused by dermatophytes, which normally do not invade beyond the epidermis. We report here one such case that occurred in an immunosuppressed individual. The patient was a 35-year-old farmer who presented with small pruritic eruption that had initially appeared on the lower leg and then had gradually spread to hair-bearing areas of the body, finally producing nodular and pustular inflammatory lesions with exacerbations and remissions. Fungal examination by direct potassium hydroxide mount and culture revealed Trichophyton rubrum. Granulomatous changes were seen on histopathological examination. The patient completely responded to systemic antifungal therapy.
Solution of an extraordinary differential equation by Adomian decomposition method
S. Saha Ray,R. K. Bera
Journal of Applied Mathematics , 2004, DOI: 10.1155/s1110757x04311010
Abstract: The aim of the present analysis is to apply the Adomian decomposition method for the solution of a fractional differential equation as an alternative method of Laplace transform.
Rapid and sensitive liquid chromatographic method for determination of paclitaxel from parenteral formulation and nanoparticles
Kollipara S,Bende G,Saha R
Indian Journal of Pharmaceutical Sciences , 2010,
Abstract: A simple and fast reversed phase liquid chromatographic method was developed for estimation of paclitaxel in commercially available parenteral formulation and nanoparticles. Separations were carried out using mobile phase consisting of acetonitrile and 20 mM potassium dihydrogen phosphate (45:55, v/v) on Lichrocart C 18 analytical column at a flow rate of 1 ml/min and detection wavelength of 230 nm. The developed method exhibited linearity over an analytical range of 50-2000 ng/ml with regression equation, mean peak area= 137.58 concentration (ng/ml)+1765.94, (R 2 =0.9999). The method demonstrated selectivity with no interfering peaks eluting near the vicinity of drug peak. The method was found to be sensitive with detection and quantification limits of 7.57 ng/ml and 22.94 ng/ml. The method has shown consistent and good recoveries from parenteral formulation (100.06±0.86%) and nanoparticles (100.43±0.91%). The method was successfully employed for the analysis of in vitro release study samples of nanoparticle formulation. The method was also applied for determination of paclitaxel content in various pharmaceutical formulations.
Optimizing Sampling, Sample Processing and Analysis Methods for Radon (222Rn) in Water by Liquid Scintillation Counting  [PDF]
Uttam K. Saha, Michael E. Kitto, Dana R. Lynch, Anchal Bangar, Pamela R. Turner, Gabrielle Dean, Leticia S. Sonon
American Journal of Analytical Chemistry (AJAC) , 2018, DOI: 10.4236/ajac.2018.91003
Abstract: Throughout the United States, laboratories use different sampling methods (“Direct Fill” vs. “Submerged Bottle” methods), sample preparations (“Simultaneous Drawing” vs. “Separate Drawing”), scintillators (“Mineral Oil” vs. “Opti-Fluor”), volume of water plus scintillator in the cocktail (“8 mL plus 8 mL” vs. “10 mL plus 10 mL”), and liquid scintillation counting assays (“Full Spectrum: 0 - 2000 keV” vs. “Region of Interest: 130 - 700 keV”) for analyzing radon (222Rn) in water. We compared these and few other variables on the recovery of radon from two “Proficiency Test (PT)” samples and four “Household Well Water” samples from Georgia. The “130 - 700 keV” assay had significantly higher radon recovery than the “0 - 2000 keV” assay. The “Direct Fill” sampling produced significantly lower radon recovery than the “Submerged Bottle” sampling. “Simultaneous Drawing” of both scintillator and water sample yielded higher radon recovery than “Separate Drawing”. Air bubble in the samples resulted in significant loss of radon gas; and such loss became greater as the air bubble was larger. A “10 mL scintillator + 10 sample” combination appeared better than “8 mL scintillator + 8 mL sample”. Mixing scintillator and sample in the laboratory, when compared with doing it on-site, was found superior for better results and practicality of testing radon in private well waters. “Mineral Oil” scintillator provided higher radon activity than “Opti-Fluor”. However, in 10 consecutive measurements of the two proficiency test (PT) samples at 60 days interval (i.e., with full ingrowing), “Mineral Oil” overestimated the radon activity compared to the predicted/assigned value in most cases, whereas “Opti-Fluor” invariably produced results close to the predicted/assigned value. There were noticeable temporal variations in both radon and uranium concentrations in the study wells; nevertheless, uranium and radon concentrations had good positive correlation. Despite this, the use of uranium concentration over 30 ppb (the MCL of uranium in drinking water) as a trigger for recommending test for radon in well water remains questionable because there may be the safe level of uranium but unsafe level of radon in a well and vice versa.
Rapid and sensitive spectrofluorimetric method for the estimation of celecoxib and flurbiprofen
Chandran S,Jadhav P,Kharwade P,Saha R
Indian Journal of Pharmaceutical Sciences , 2006,
Abstract: In this study new, rapid and sensitive spectrofluorimetric methods for the quantitative estimation of celecoxib and flurbiprofen in pure form and in their pharmaceutical dosage forms were developed. The solvent systems, wavelengths of detection (excitation and emission) were optimized in order to maximize the sensitivity and minimize the cost of analysis for both the drugs. No extraction procedure was employed for analysis of these compounds in their formulation matrix, which reduced the time of sample preparation. The excitation and emission wavelengths were found to be 256 nm and 403 nm respectively for celecoxib in water and 250 nm and 314 nm respectively for flurbiprofen in 1:1 mixture of methanol and 0.1N sulphuric acid. The linear regression equations obtained by least square regression method for fluorescence intensity (FI) and concentration in ng/ml (conc) were FI=1.2874′conc+22.647, for celecoxib; and FI=27.7970′conc+46.049, for flurbiprofen. The limit of detection as per the error propagation theory was found to be 4.97 ng/ml and 0.99 ng/ml for celecoxib and flurbiprofen respectively. The developed methods were successfully employed with high degree of precision and accuracy for the estimation of total drug content in two commercial capsule formulations of celecoxib and two ophthalmic drops of flurbiprofen. The results of analysis were treated statistically, as per International Conference on Harmonization guidelines for validation of analytical procedures, and by recovery studies. It was concluded that developed methods are simple, accurate, sensitive, precise and reproducible and could be applied directly and easily to the pharmaceutical preparations of celecoxib and flurbiprofen.
Correlation dimension and topological entropy in discrete maps
L. M. Saha,S. Prasad,R. K. Mohanty
Applied Mathematical Sciences , 2012,
Abstract:
Isoflavone in Postmenopausal Women - Are They Really Effective? A Prospective Case Control Study.
TS Bag,Amit Kyal,DP Saha,R Dutta,S Mondal
Nepal Journal of Obstetrics and Gynaecology , 2012, DOI: 10.3126/njog.v7i1.8826
Abstract: A prospective case control study was conducted at Medical College, Kolkata with the aim of evaluating the role of isoflavone( a class of phytoestrogen –plant compounds having the beneficial effects of estrogen but lesser risks and side effects) in postmenopausal women. 100 postmenopausal women (those who underwent total abdominal hysterectomy and bilateral salpingooopherectomy for different benign indications, aged between 40-50 years and who were menstruating before operation) were alternately distributed into two groups-Group A (n=50, received 60mg of isoflavone and 500mg of calcium per day for 6 months) and Group B (n=50, received 500mg of calcium per day only for 6 months). To evaluate the menopausal symptoms, the menopausal Kupperman index questionnaire was applied. Other outcomes measured were body mass index, blood pressure and lipid profile. Menopausal symptoms in Group A(those using isoflavones) were lower compared to Group B. The present study showed that Kupperman index decreased significantly in Group A (from 28.48 ± 2.03 to 16.32 ± 1.06 i.e. 45% decline) compared to Group B (from 24.56 ± 1.52 to 18.44 ± 1.11 i.e. 25% decline). No differences in blood pressure or body mass index were found during treatment between the two groups. . In our study total cholesterol, triglycerides and low-density lipoproteins (LDL) decreased significantly in Group A compared to Group B. Therefore our clinical study indicates that isoflavone can be an invaluable resource for postmenopausal women for combating menopausal symptoms. Nepal Journal of Obstetrics and Gynaecology / Vol 7 / No. 1 / Issue 13 / Jan- June, 2012 / 11-14 DOI: http://dx.doi.org/10.3126/njog.v7i1.8826
Evolution of bulk superconductivity in SrFe2As2 with Ni substitution
S. R. Saha,N. P. Butch,K. Kirshenbaum,Johnpierre Paglione
Physics , 2009, DOI: 10.1103/PhysRevB.79.224519
Abstract: Single crystals of the Ni-doped FeAs-based superconductor SrFe2-xNixAs2 were grown using a self-flux solution method and characterized via x-ray measurements and low temperature transport, magnetization, and specific heat studies. A doping phase diagram has been established where the antiferromagnetic order associated with the magnetostructural transition of the parent compound SrFe2As2 is gradually suppressed with increasing Ni concentration, giving way to bulk-phase superconductivity with a maximum transition temperature of 9.8 K. The superconducting phase exists through a finite range of Ni concentrations centered at x=0.15, with full diamagnetic screening observed over a narrow range of x coinciding with a sharpening of the superconducting transition and an absence of magnetic order. An enhancement of bulk superconducting transition temperatures of up to 20% was found to occur upon high-temperature annealing of samples.
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