Modelling and simulation on behaviours of mild steel

The objective of the paper is to simulate the behaviours of mild steel at different strain rates (1-1500s-1) under tension and compression by using finite element analysis code in ANSYS. Numerical simulation are done using Cowper-Symonds (C-S) and Johnson-Cook (J-C) material models to represent the flow stresses of mild steel. The simulated results have good agreement with the predicted results of the above material models

Efficacy of terbutaline in preterm labour - our experience

Background: Preterm birth is one of the important causes of perinatal mortality and morbidity in developed countries after congenital malformations. Postponement of delivery plays essential role in preventing such incidences by allowing fetal lung maturity.Methods: This is a prospective study conducted over a period of 20 months among the patients admitted for preterm labour with gestational period between 27 to 36 weeks. After the patients obeyed all the inclusion criteria, they were administered terbutaline 250 µg subcutaneously every 8th hourly followed by 5 mg tablet orally twice daily till contractions ceased. The patients were analysed for gestational period at which they presented with preterm labour contractions, associated risk factors, response to terbutaline, and gestational period at delivery, perinatal complications, neonatal and maternal outcomes. The data obtained were analysed by descriptive analysis.Results: There were 1,678 deliveries during study period, out of which 207 (12%) presented with preterm labour and 20 (~10%) patients received terbutaline. Idiopathic (50%) and vaginal infections (25%) were common causes of preterm labour among the patients who received terbutaline. The labour was prolonged by 3 - 5 days among 8 patients, 7 - 15 days in 9 patients and 15 - 30 days in 3 patients. Common maternal side effects were nausea and tremors. Neonatal outcome was good in most of the cases except in 5 (25%) neonates who required NICU admission but they all recovered well without any morbidity.Conclusions: Administration of terbutaline prolonged labour without any serious maternal complications and better neonatal outcome as 90% of the neonates were born without any complications. Hence, terbutaline can be used as a safe and effective tocolytic agent among patients presenting with preterm labour

Effect of Heat Stress on Milk Production and Composition in Murrah Buffaloes

Temperature humidity index (THI) is widely used to assess the effect of temperature and relative humidity on performance in animals. In summer the THI was between 74 - 89 with average value of 81.18. in winter months THI ranged between 49 -70 with the average of 60. The results showed a significant effect of heat stress on daily milk yield and milk composition. In the present study the daily milk yield decreases from 4.46 to 3.65kg, heat stress reduced milk yield by 18.2%. There was a significant effect of heat stress on milk composition. Heat stress significantly reduced milk fat content from 8.3% during the winter to 7.19% during the summer. Milk protein percentage significantly decreased as a result of summer heat stress (3.08 vs.2.9 %, respectively for the winter and summer). In the present study the SNF decreases from 9.08 to 9.05 %, heat stress reduced SNF % as the THI value went from > 74 to  83 in summer. Results showed that milk production is a function of THI. The negative slope of regression line indicates that milk production fat%, protein% and SNF% decreases as THI increases. This regression indicates that in general for each point increase in THI value. There was decrease in milk yield of 0.028kg per buffalo per day. Heat stress environments have been associated with depression in milk fat%, protein% and SNF%. There was decrease in milk fat of 0.046% per buffalo per day. There was also decrease in milk protein of 0.00014 % per buffalo per day. The decrease in milk SNF of 0.0047 % per buffalo per day

Tribological Experimentations with Jatropha Biofluid and Nanoparticles as Lubricant Additives

The use of vegetable oils as lubricants in automobiles is rapidly increasing due to the prevailing environmental aspects. Vegetable oils are also suitable for other applications because they come from renewable and sustainable natural sources and have high biodegradability and low toxicity. Nanoparticles have been extensively investigated for a long time as potential performance improvers of traditional antifriction and antiwear additives because of their inherent properties such as size and shape. The primary aim of the study is to investigate the use of jatropha oil mixed with graphite, molybdenum disulfide (MoS2), and titanium dioxide (TiO2) nanoparticles as a nanoparticle biolubricant. The nanoparticles of graphite, molybdenum disulfide, and titanium dioxide are added in varying weight percentages to jatropha oil and a tribological analysis is carried out using a pin-on-disc tribometer. The analysis is focused on tribological quantities, such as coefficient of friction, wear volume, and frictional force. The experiment was carried out for 5 minutes under varying loads at different disc speeds. At an optimum concentration of nanoparticles, the coefficient of friction, frictional force, and the wear rate were found to have the lowest values, but when the level of nanoparticles increases above the optimum level, the friction coefficient and wear rate seem to be increased. The pin-on-disc experiments revealed that nanographite powder mixed in jatropha oil gives better tribological performance than the other two tested nanopowders. Subsequently, multiple regression models are developed using input and output variables. A non-linear fit between the response and the corresponding significant parameters is considered

(E)-3-[2-(4-Chloro­phenyl­sulfon­yl)vin­yl]-6-methyl-4H-chromen-4-one

In the title compound, C18H13ClO4S, the mean planes of the chloro­phenyl ring and the S—C=C—C chain are oriented at angles of 52.7 (2) and 51.3 (2)°, respectively, with respect to the sulfonyl (O=S=O) plane. The dihedral angle between the mean planes of the chloro­phenyl group and the benzopyran ring is 80.7 (1)°. The crystal structure is stabilized by two inter­molecular C—H⋯O inter­actions, forming centrosymmetrc dimers, which are linked via a second C—H⋯O inter­action into a chain structure

PROTOTYPE SELF EMULSIFYING SYSTEM OF ETRAVIRINE: DESIGN, FORMULATION AND IN VITRO EVALUATION

Objective: Lipid-based formulations have gained much attention, particularly on self-emulsifying drug delivery systems (SEDDS), to improve the oral bioavailability of lipophilic drugs. In the present study, an attempt was made to develop and evaluate prototype SEDDS of poorly soluble antiviral BCS class IV drug etravirine.Methods: Various oils, surfactants and co-surfactants were screened for their suitability in the formulation of SEDDS. Based on the screening, gelucire 44/14, as the oil, labrasol as a surfactant and transcutol HP as the co-surfactant were selected. SEDDS with drug etravirine was formulated and evaluated for emulsifying ability, dilution potential and microscopic properties. The emulsion area for each of the combination of oil and surfactant co-surfactant mixture (Smix) was determined by the construction of pseudo-ternary phase diagrams.Results: The optimized formulation with oil (gelucire 44/14) and Smix (labrasol: transcutol HP, 6:1) in a ratio of 2:8 exhibited a rapid emulsification rate and a good polydispersibility index of 0.103±0.012 indicating uniformity of the formed droplets. The size of the droplets was determined by zetasizer and was found to be in 200 nm range. The drug release from the final formulation after 2hr was found to be 41.15%±0.5 compared to 19.3%±3.8 of pure drug indicating enhanced dissolution profile of the drug.Conclusion: In vitro study illustrated enhanced dissolution rate of formulated prototype SEDDS of BCS class IV drug etravirine for oral delivery