Superconducting Bearing Design for Outer Rotor Flywheel Using Lumped Parameter Techniques

This paper describes the application of lumped parameter modeling techniques to designing high temperature superconducting bearings for outer-rotor flywheel energy storage systems. The lumped parameter models decrease computational time by 99% compared to Finite Element Analysis (FEM) without compromising fidelity needed to capture the non-linear and hysteretic force-displacement behavior between a levitated permanent magnet and bulk superconductor. The techniques formulated can be used to quickly evaluate lifting capacity and translational stiffness for a superconducting bearing design. The validity of the modeling approach has been verified by comparing results from FEM studies and experimental tests.Center for Electromechanic

Practice of wastewater irrigation and its impacts on human health and environment: a state of the art

The practice of wastewater irrigation lessens the pressure on the aquatic environment by minimizing the use of freshwater resources. However, this may lead to significant damage to the human health and environments. Recycled wastewater possesses a substantial amount of nutrients that act as fertilizers for crops and facilitate the metabolic action of microorganisms. The major advantages of wastewater irrigation are increased agricultural production, nutrient recycling, reduced stress on freshwater, economical support and provision of livelihoods for farmers. However, several harmful impacts of wastewater irrigation are also prominent due to inappropriate wastewater management and irrigation practices. These include severe hazards to farmer’s health, contamination of agricultural land and crops with toxic metals, chemical compounds, salts and microbial pathogens. In addition, long-term irrigation using wastewater can significantly affect the groundwater through leakage of salty and toxic metal-rich wastewater making it unfit for human consumption. Wastewater irrigation may also alter the physicochemical properties and microbiota of soil, which in turn can disturb land fertility and crop productivity. Several factors need to be considered while using treated or partially treated wastewater for irrigation such as diversity and type of pollutants, available nutrients, pathogenic microorganisms and soil salinity. In this review paper, we assess the impact of wastewater irrigation on humans as well as on the environment based on available case studies globally, outline current use of wastewater for irrigation of agricultural crops such as cereals, vegetables, fodder crops, including agroforestry and discuss suitable management practices of wastewater reuse for irrigation

Nutritional Status of School Children Aged 8-12 Years in Deprived Areas of Mauritius

This study investigated the nutritional status of school children in deprived areas of Mauritius and determined whether specific socio-economic factors were associated with poor nutritional status among children. A cross-sectional survey was conducted among 240 primary school children aged 8-12 years old. Out of 27 schools located in the deprived regions of Mauritius, eight of them were selected for the study. The data collection tools included a questionnaire, anthropometric measurements (weight and height) and a 24-hour dietary recall. A questionnaire was used to gather information on the socioeconomic profile of the children and their eating patterns. The Centre for Disease Control (CDC) BMI-for-age and stature-for-age percentiles were used to identify children who were stunted (<5th percentile stature-for-age), underweight (< 5th BMI-for age percentile), overweight (85th to 95th percentile BMI-for age) or obese (≥95th percentile BMI-for-age). Findings revealed that the main meals taken by the children included breakfast, lunch and dinner. Ninety two percent of the children mentioned taking breakfast in the morning; the most commonly consumed food commodities being bread, margarine, cheese, jam and tea; milk, yoghurt, fruits or fruit juice were rarely consumed. Packed lunches consisted mainly of eggs and convenience foods such as sausages without any vegetables. Poor snacking habits, that is, high consumption of salty corn-based snacks, were identified among these children. Age of school children was significantly associated (p<0.05) with the amount of money spent on snacks at school. Anthropometric measurements revealed the prevalence of both undernutrition and overnutrition among the children. Thirty seven per cent of the children were underweight, four per cent were overweight, three per cent were obese and there were no cases of stunting. The study findings indicate that the children are being fed the wrong kinds of foods or the wrong proportions. Thus, there is a need for local education and health authorities to develop nutrition education programmes that are contextually sensitive to specifically target school children and parents in deprived areas of Mauritius.Key words: Nutritional status, deprived children, Mauritiu

Tenapanor: new approach to counter irritable bowel syndrome with constipation

Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder chronic in nature and characterized predominantly by abdominal pain or discomfort associated with altered bowel habits, diagnosis requires characteristic symptoms during the last 3 months and onset ≥6 months ago. Symptom-based approaches for functional bloating, constipation and diarrhea are best utilised to identify IBS. IBS with constipation exerts significant impairment on work productivity by hampering quality of life. Inadequate relief by existing modalities, persistent hard stools and visceral abdominal pain demanded further clinical research. Tenanapor a novel molecule acts locally on gastrointestinal sodium/hydrogen exchanger isoform 3 (NHE3), an antiporter a counter transporter and exert antinociceptive effects on visceral sensation thereby decreases the frequency of abdominal pain. Action on NHE3 receptors located on small intestine and colon’s apical surface reduces the absorption of sodium and phosphate, with minimal systemic exposure. NHE3 Inhibition induced sodium absorption results in increase in water secretion into intestinal lumen resultant an accelerated intestinal transit time and softer stool consistency. Most common adverse reactions (≥2%) are diarrhea, abdominal distension, flatulence and dizziness. The drug is metabolised mainly by CYP3A4/5 and excreted in feaces (70%) and urine (7%). Tenapanor’s minimal systemic absorption is likely to be associated with a relatively inert safety and tolerability profile. Based on positive results from the phase III T3MPO trial program, tenapanor demonstrated promising results for IBS-C management and received US Food and Drug Administration approval as IBSRELA @ Ardelyx Pharma in September 2019 and augment existing modalities for management of IBS-C

Amisulpride: tackling postoperative nausea and vomiting not a nightmare any more

Vomiting and nausea remains concern in postoperative patients for anaesthesiologists and surgeons. Patients remain at risk for adverse medical consequences as wound dehiscence, dehydration, electrolyte derangement’s and gastric aspiration. This entity delays discharge and is one of the causes of unanticipated admission after ambulatory surgery. Presently dopamine (D2), serotonin (5-HT3), and histamine (H1) antagonists are widely used prophylactic agents, as is the corticosteroid dexamethasone, but the incidence of postoperative nausea and vomiting (PONV) is still appreciable. Safety concerns as QT interval prolongation has led to nearly phasing out of use of D2-antagonist Droperidol, a potent and most favoured formulation. With minimal studies and randomized studies to back up the efficacy of existing modalities viz 5HT-antagonist, promethazine, metoclopramide and dimenhydrinate for management of postoperative nausea and vomiting, need for evaluation, study and incorporation into formulary for management was always persisting. Amisulpride is an anti-psychotic agent, used routinely in >50 countries worldwide is a potent but atypical D2-antagonist with minimal adverse profile mainly QT interval prolongation, extrapyramidal signs and symptoms, which had plagued out other members of same class. In addition to D2 antagonism this drug exhibits potent antagonist action against D3 receptors, implicated in the emetic response. In pre clinical studies and multiple randomized controlled multicenter studies the effectiveness and safety of low dose intra venous Amisulpride was established and approved as Barhemsys @Acacia Pharma by US Food and drug administration in February 2020. This drug will soon add to protocol-based management of PONV

Physicochemical characterization and in vitro dissolution studies of solid dispersions of ketoprofen with PVP K30 and d-mannitol

AbstractAim of the present study was to improve the solubility and dissolution rate of poorly water soluble, BCS class-II drug Ketoprofen (KETO) by solid-dispersion approach. Solid dispersions were prepared by using polyvinylpyrrolidone K30 (PVP K30) and d-mannitol in different drugs to carrier ratios. Dispersions with PVP K30 were prepared by kneading and solvent evaporation techniques, whereas solid dispersions containing d-mannitol were prepared by kneading and melting techniques. These formulations were characterized in the liquid state by phase-solubility studies and in the solid state by Differential Scanning Calorimetry (DSC), Fourier Transform Infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). The aqueous solubility of KETO was favored by the presence of both carriers. The negative values of Gibbs free energy illustrate the spontaneous transfer from pure water to the aqueous polymer environment. Solid state characterization indicated KETO was present as fine particles in d-mannitol solid dispersions and entrapped in carrier matrix of PVP K30 solid dispersions. In contrast to the very slow dissolution rate of pure KETO, dispersions of drug in carriers considerably improved the dissolution rate. This can be attributed to increased wettability and dispersibility, as well as decreased crystallinity and increase in amorphous fraction of drug. Solid dispersions prepared with PVP K30 showed the highest improvement in dissolution rate of KETO. Even physical mixtures of KETO prepared with both carriers also showed better dissolution profiles than those of pure KETO

Dynamics of unvisited sites in presence of mutually repulsive random walkers

We have considered the persistence of unvisited sites of a lattice, i.e., the probability $S(t)$ that a site remains unvisited till time $t$ in presence of mutually repulsive random walkers. The dynamics of this system has direct correspondence to that of the domain walls in a certain system of Ising spins where the number of domain walls become fixed following a zero termperature quench. Here we get the result that $S(t) \propto \exp(-\alpha t^{\beta})$ where $\beta$ is close to 0.5 and $\alpha$ a function of the density of the walkers $\rho$. The number of persistent sites in presence of independent walkers of density $\rho^\prime$ is known to be $S^\prime (t) = \exp(-2 \sqrt{\frac{2}{\pi}} \rho^\prime t^{1/2})$. We show that a mapping of the interacting walkers' problem to the independent walkers' problem is possible with $\rho^\prime = \rho/(1-\rho)$ provided $\rho^\prime, \rho$ are small. We also discuss some other intricate results obtained in the interacting walkers' case.Comment: 6 pages, 7 figure