Rejuvenating Green OA for a Greener Pasture

This paper is a critical sequel to John Dove’s paper titled “Maximum Dissemination: A possible model for society journals in the humanities and social sciences to support Open while retaining their subscription revenue”, presented at the Charleston Conference 2019. Dove’s OA advocacy has included both gold and green. Dove’s innovative model, which makes full use of the green route to achieve maximum dissemination of authors’ works through open repositories, suggests a switch in the functional responsibility for depositing author’s manuscript from author to publisher. The model has publishers to act as agents of the authors as much through the green route as their subscription route. Dove has suggested this maximum use of the green path by the publisher for specific journals in specific disciplines. This paper looks to examine the feasibility of green OA model in this context, and then to consider other ways to expand on this idea to other green OA supporting publishers. It further looks at the possibilities of the model driving the re-emergence of green OA as a favoured option for facilitating immediate and parallel dissemination of authors’ papers through both green and subscription channels

A Study of Phenylephrine Administration for the Prevention and Treatment of Hypotension in Cesarean Section during Spinal Anaesthesia

Background: Hypotension remains the most common complication following spinal anesthesia in cesarean sections. Despite using various preventive measures, hypotension occurs in most cases; vasopressors are often required. The current study evaluated the safety and efficacy of prophylactic phenylephrine infusion in preventing spinal anesthesia-induced hypotension in the Cesarean Section. Materials and Methods: A total of 50 parturients aged 20-35 years with American Society of Anesthesiologists (ASA) grade II, scheduled for elective cesarean sections were randomly allocated into one of the two groups. Group A (n=25) received intravenous prophylactic phenylephrine infusion at 100μg/min for 3min after spinal anesthesia using a syringe pump. Each minute, systolic arterial pressure (SAP) was measured, and infusion stopped if SAP > baseline and continued if less than or equal to baseline systolic arterial pressure. Intravenous phenylephrine bolus 100μg was given when SAP decreased to <80% of baseline. Group B (n=25) received only intravenous phenylephrine bolus 100μg when SAP decreased to <80% of baseline. After 1 minute of spinal anesthesia, Heart Rate (HR), SAP, and diastolic blood pressure (DBP) were recorded every minute until the baby's extraction. After the delivery of the baby, APGAR scores at 1 minute and 5 minutes were noted. Umbilical artery blood was sent for analysis of the pH. The total volumes of study solutions given up to the time of delivery of the baby were recorded. Results: Phenylephrine infusion decreased the incidence and frequency of hypotension compared with control and the phenylephrine dose was much higher in the infusion group than in the control group (p=0.0001). None of the patients had any incidence of nausea or vomiting. There was no significant difference in umbilical artery blood pH and no reduction in the APGAR scores. HR was significantly slower in the infusion group compared with the control group. Conclusion: A prophylactic infusion of phenylephrine100 μg/min in patients receiving spinal anesthesia for elective cesarean delivery decreased the incidence of hypotension and without any deleterious neonatal outcome

VALIDATED SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF CHLORAMPHENICOL IN PURE AND IN ITS DOSAGE FORM

Objective: A simple, economic, selective, precise, and accurate UV-Visible spectrophotometric method for the analysis of Chloramphenicol in bulk drug and pharmaceutical formulations was developed and validated in the present study. Methods: Based on oxidative coupling reaction with MBTH reagent at PH-4.5 which is extractable at 620 nm. The Beer's law is obeyed in the concentration range 1-6 ml (10-60 µg ml-1). Results: The RSD was found to be 0.0194% and recovery is 99.73%. The method was completely validated and proven to be rugged. The interferences of the ingredients and recipients were not observed. The repeatability and the performance of the proved method were established by point and internal hypothesis and through recovery studies. Conclusion: The method was found to be accurate and precise, as indicated by recovery studies close to 100 and % RSD is not more than 2. The summery of validation parameters of proposed UV-Visible method is given

VALIDATED SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF CHLORAMPHENICOL IN PURE AND IN ITS DOSAGE FORM

A simple, précis, rapid sensitive and accurate spectrophotometric methods have been developed for the estimation of Chloramphenicol UV in pure form and its pharmaceutical formulations based on oxidative coupling reaction UV with MBTH reagent at P H-4 which is extractable at 620 nm. Beer's law is obeyed in the concentration range 1-6 ml (10-60 µgml-1). The developed method was applied directly and easily for the analysis of the pharmaceutical formulations. RSD was found to be 0.0194 % and recovery 99.73%. The method was completely validated and proven to be rugged. The interferences of the ingredients and excipients were not observed. The repeatability and the performance of the proved method were established by point and internal hypothesis and through recovery studies.Keywords: Spectrophotometry, Chloramphenicol, MBTH, Oxidative coupling

VSI fed IM drive employing look-up tables with 6&12 sectors

Since the IM drives play a vital role for variable speed applications from fractional horse power to multi Mega-watt power, the control and estimation of induction motor drives constitute a vast subject. Nowadays, vector control and direct torque control (DTC) are popular for high performance drives. Even though these methods give better performance, the vector control method needs reference frame transformations and direct torque control gives large steady state ripples. To overcome these problems in the above methods mentioned, this paper presents an advanced vector control method for voltage-source inverter fed induction motors using sophisticated look-up tables. This method uses a predetermined look-up table instead of a much more time consuming pulse width modulation (PWM) procedure in conventional vector control for generating inverter gate signals. This approach gives faster torque response like in vector control methods and it also reduces ripples as in DTC method. To validate the proposed method numerical simulations have been carried out and compared with the existing algorithms. The simulation results confirm the effectiveness of the proposed method