159 research outputs found

    High Power, Continuous-wave Supercontinuum Generation in Highly Nonlinear Fibers Pumped with High Order, Cascaded Raman Fiber Amplifiers

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    A novel method for efficient generation of high power, equalized continuous-wave supercontinuum source in an all conventional silica fiber architecture is demonstrated. Highly nonlinear fiber (HNLF) is pumped in its anomalous dispersion region using a novel, high power, L-band laser. The L-band laser encompasses a 6th order cascaded Raman amplifier which is pumped with a high power Ytterbium doped fiber laser and amplifies a low-power, tunable L-band seed source. The supercontinuum generated 35W of power with ~40% efficiency. The Supercontinuum spectrum was measured to have a high degree of flatness of better than 5 dB over 400 nm of bandwidth (1.3 - 1.7 micron, limited by spectrum analyzer range) and a power spectral density in this region of >50 mW/nm. The extent of the SC spectrum is estimated to be upto 2 micronComment: 6 pages, 5 figure

    Comprehensive study of Sheetada, Dantavesta, Upakusha, Dantapupputa

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    According to Ayurvedic perspective of diseases related to oral cavity Acharyas have explained Nidana, Samprapti, Lakshana, Chikitsa of all the Avayava of Mukha in detail. According to Sushruthacharya’s classification of Dantamoolagata Roga, he had enumerated 15 Rogas and among them, Sheetada, Dantaveshta, Upakusha and Dantapupputta are commonly encountered diseases in the clinical practice. Kapha Dosha and Rakta Dhatu are the main factors involved in the pathology of these diseases and management of these conditions includes, Stanika Upakramas such as Pratisarana, Kavala, Gandoosha, Lepa and systemic therapies like Vamana, Virechana and Nasya are advocated. The above said 4 clinical conditions can be co-related to different stages of   periodontal diseases. Gingivitis is the inflammation of gum & periodontitis is inflammatory disease of the supporting tissues of the teeth. If left untreated, it may progress to periodontitis (destructive form). In our classics, each Mukha Avayava is described with its clinical features and treatment measures indicating their significance in maintaining Swasthya. In early detection, it is fairly simple to help, treat and prevent

    Nanomechanics of membrane tubulation and DNA assembly

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    We report an interesting regime of tubule formation in multilamellar membrane vesicles. An optically trapped bead is used to apply a localized subpicoNewton force on a cationic vesicle to form a membrane tubule. The force extension curves reveal a saturation phase, with the tubule length extending up to tens of microns, beyond a threshold force 0.6±0.2 pN. We then use the tubule as a sensor for monitoring the dynamics of charge induced DNA integration on cationic membrane vesicles. Our results may also have applications in the development of nanowires and nanofluidic devices

    EXTRACTION OF TARTARIC ACID FROM TAMARIND PULP AND ANALYSIS OF THE ACID COMPOSITION IN LEAVES

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    Tamarind a naturally obtained, long lived, evergreen and less expensive raw material. It comprises organic acids like high content of tartaric acid 12-18%, malic acid, citric acid and byproducts like pectin, potassium Bitartrate. The purpose of this research was to extract the tartaric acid from tamarind pulp by hot and cold extraction followed by cooling and by addition of less expensive chemicals. The obtained solid form of acid detected with NMR Spectra and its concentration analyzed with UV spectrophotometer using metavanadate. Where as the composition of acid in powdered form of leaves explored with two methods. By organic extraction using suitable solvent, the composition of acid in leaves is extracted using own making equipment percolator with small lab scale apparatus and waste material like plastic drink bottle and another method is soxhlet apparatus. The extracts obtained from process are added with another suitable solvent and were analyzed by Thin Liquid Chromatography. As a whole the process becomes economically more competitive than other process and to utilize the product in both traditional and agricultural applications

    High Power, Tunable, Continuous-Wave Fiber Lasers in the L-band using Cascaded Raman Amplifiers

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    We demonstrate a high power, all-fiber, tunable laser source that can operate in the L-band region. A low power, tunable input laser is amplified with a recently proposed, high efficiency, 6th order cascaded Raman amplifier. The proposed system is scalable and overcomes the limitations of Erbium and Erbium-Ytterbium co-doped fiber lasers for power scaling. A tunable Erbium-Ytterbium co-doped fiber ring laser generating ~0.5W of power and tunable in the 1560-1590 nm wavelength range is utilized as the seed source. The output from the seed laser is amplified to ~24 W using 6th order cascaded Raman amplification. A high power Yb laser operating at 1117nm is used as the pump laser for driving the Raman conversions. The operating wavelength of the demonstrated laser in the eye-safe, atmospherically transparent region enables high power free-space applications. In addition, this source enables other interesting applications such as high power supercontinuum generation with conventional silica fibers.Comment: 6 pages, 5 figure

    Is low amniotic fluid index an indicator of fetal distress and hence delivery?

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    Background: Amniotic fluid Index (AFI) is an indicator of fetal well-being. Low AFI is considered to be one of the indications for delivery as it may be associated with fetal distress and birth asphyxia. We sought to determine whether low AFI is an indicator of fetal compromise and an indication to deliver.Methods: This prospective, observational study was conducted at Department of Obstetrics & Gynecology, KMC, Manipal University, India, between August 2013 and Aug 2014. A total of 150 subjects that had induced labor or direct caesarean section for various indications and also having low-normal (5-8) / low (<5) AFI, were recruited. Subjects with fetal anomalies were excluded. Outcome variables studied were, fetal distress in labor, thick meconium stained amniotic fluid, mode of delivery in induced labor, perinatal asphyxia, and respiratory distress syndrome.Results: Out of 150 subjects, 68 (45.4%) had low and 82 (54.6%) had low-normal AFI. Both the groups were matched for demographic characteristics and confounding factors for neonatal outcome. In low AFI group the incidence of Low APGAR (11.7%), perinatal asphyxia (11.7%) and RDS (16.1%) were significantly higher compared to those in low-normal group (3.6%, 1.2% and 2.4% respectively) p = 0.057, 0.006 and 0.002. There was no significant difference between the groups with respect to mode of delivery when labor was induced.Conclusions: Low AFI, especially when it is <5, is an indicator of fetal compromise and one may anticipate perinatal asphyxia and RDS. Hence it is prudent to contemplate delivery when the AFI is between 5 and 8

    Case report-baboon syndrome with paracetamol

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    Adverse drug reaction (ADR) is defined as “any response to drug which is noxious or unintended and occurs at a dose normally used in man for prophylaxis, diagnosis or treatment of diseases or for modification of physiological function”. Among the ADRs reported, cutaneous drug reactions are most common. Symmetrical drug-related intertriginous and flexural exanthema (SDRIFE), also known as baboon syndrome (BS), is included in the spectrum of systemically induced allergic contact dermatitis. Characteristics of SDRIFE include a sharply defined symmetric erythema in the gluteal area and in the flexural or intertriginous folds without any systemic symptoms or signs. We present a case of 30-year-old female with baboon syndrome after taking the combination of paracetamol and diclofenac. Awareness of SDRIFE (BS) as an unusual drug reaction is especially important since the connection between skin eruption and drug exposure may easily be overlooked or misdiagnosed

    Evaluation of hypolipidemic effect of Tinospora cordifolia in cholesterol diet induced hyperlipidemia in rats

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    Background: There is always a need for developing novel drugs with higher efficacy and fewer side effects. Though statins are generally well-tolerated drugs for hyperlipidemia with high efficacy they are not free from adverse effects. Herbal drugs are well known for their cost-effectiveness and minimal side effects. Tinospora cordifolia (T. cordifolia) is one such plant with known hypolipidemic activity and wide availability in India. Hence this study is an attempt to verify and evaluate the extent of efficacy of T. cordifolia as a hypolipidemic agent. The objective of the study is to compare the hypolipidemic activity of aqueous root extract of T. cordifolia with that of Rosuvastatin in cholesterol diet-induced hyperlipidemia in rats.Methods: Hyperlipidemia was induced in male albino rats of wistar strain in the first 30 days of feeding period and continued in the next 30 days of treatment period. Aqueous root extract of T. cordifolia (2.5 and 5g/kg, per oral) was administered as test drug in the treatment period. Rosuvastatin (10 mg/kg,      per oral) was used as the standard drug. Serum lipid profile, atherogenic index and body weights were estimated for all rats on the day before the start of the feeding period and on day 0, 15 and 30 of the treatment period. The results were analyzed statistically using student’s unpaired and paired t-test wherever applicable.Results: Serum lipid levels showed significant reduction (p <0.001) in TC,TG, LDL-C and VLDL-C with significant elevation (p <0.001) of HDL-C in both the rosuvastatin and test groups, but the percentage reduction in lipid levels, percentage elevation of HDL-C and percentage protection from atherosclerosis was higher in rosuvastatin group than in test groups.Conclusions: T.cordifolia has a definite hypolipidemic potential. Although its effectiveness is lesser than rosuvastatin its beneficial role as hypolipidemic agent may be tested in clinical studies

    Evaluation of hypolipidemic effect of Tinospora cordifolia in cholesterol diet induced hyperlipidemia in rats

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    Background: There is always a need for developing novel drugs with higher efficacy and fewer side effects. Though statins are generally well-tolerated drugs for hyperlipidemia with high efficacy they are not free from adverse effects. Herbal drugs are well known for their cost-effectiveness and minimal side effects. Tinospora cordifolia (T. cordifolia) is one such plant with known hypolipidemic activity and wide availability in India. Hence this study is an attempt to verify and evaluate the extent of efficacy of T. cordifolia as a hypolipidemic agent. The objective of the study is to compare the hypolipidemic activity of aqueous root extract of T. cordifolia with that of Rosuvastatin in cholesterol diet-induced hyperlipidemia in rats.Methods: Hyperlipidemia was induced in male albino rats of wistar strain in the first 30 days of feeding period and continued in the next 30 days of treatment period. Aqueous root extract of T. cordifolia (2.5 and 5g/kg, per oral) was administered as test drug in the treatment period. Rosuvastatin (10 mg/kg,      per oral) was used as the standard drug. Serum lipid profile, atherogenic index and body weights were estimated for all rats on the day before the start of the feeding period and on day 0, 15 and 30 of the treatment period. The results were analyzed statistically using student’s unpaired and paired t-test wherever applicable.Results: Serum lipid levels showed significant reduction (p <0.001) in TC,TG, LDL-C and VLDL-C with significant elevation (p <0.001) of HDL-C in both the rosuvastatin and test groups, but the percentage reduction in lipid levels, percentage elevation of HDL-C and percentage protection from atherosclerosis was higher in rosuvastatin group than in test groups.Conclusions: T.cordifolia has a definite hypolipidemic potential. Although its effectiveness is lesser than rosuvastatin its beneficial role as hypolipidemic agent may be tested in clinical studies
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