Evaluation of fluoride bioremediation and production of biomolecules by living cyanobacteria under fluoride stress condition.

Application of microalgae for defluoridation has gained interest in recent years. In the present study, bioremediation of fluoride using living cyanobacteria, Starria zimbabweensis, collected from wastewater of coke-oven effluent treatment plant, Durgapur, India, has been investigated. Initially, the cyanobacterial strain was grown in BG11 medium at 25°C, 45µmol/m2/s irradiation in 18h: 6h light:dark cycle in an algal incubator. Samples were withdrawn after 2 days interval and analyzed for its dry biomass and lipid content. Optimum inoculum size of 10% and age of 16th day were assessed based on maximum dry biomass (9.307 ± 0.01g/L) and lipid (244.05 ± 0.02mg/L) production. SEM-EDX and FTIR studies of both native and fluoride treated biomass were done to emphasize the changes. During kinetic study of defluoridation, initial fluoride concentration was varied in the range of 10-50mg/L. Maximum fluoride removal (66.6 ± 0.11%) and dry biomass (18.19 ± 0.12g/L) were obtained at 10mg/L fluoride concentration using 10% of 16th day's inoculum. Biomass and lipid content were found to increase 2 and 4 folds, respectively under fluoride stress condition. Furthermore, chlorophyll, carbohydrate and protein content of the biomass were also compared between control and fluoride contaminated conditions. Fatty Acid Methyl Ester (FAME) analysis was done using Gas Chromatography (GC) to compare the lipid profile of native and fluoride loaded strain.

Valorization of waste micro-algal biomass - collected from coke oven effluent treatment plant and evaluation of sorption potential for fluoride removal.

Fluoride contamination in groundwater is now becoming a global concern. In the present study, removal of fluoride using dry biomass (DBM) of a micro-algal consortium of Chlorococcum infusionum and Leptolyngbya foveolaurum, collected from a coke-oven effluent treatment plant, Durgapur, India, has been investigated. The large volume of algal bloom in the industrial effluent has created serious disposal issues and caused severe environmental concerns. A biosorption technique has been carried out to valorize the waste algae biomass into a potential adsorbent. Response Surface Methodology (RSM) is used to model and optimize fluoride removal. Maximum fluoride removal (72%) is obtained at pH 4, 5 mg/L initial fluoride concentration, 0.5 g/L adsorbent dose (AD), and 25 °C temperature during one-factor-at-a-time (OFAT) analysis. The optimum condition of removal as specified by RSM is - initial concentration of fluoride: 30 mg/L, pH: 4.5, AD: 3.5 g/L and temperature: 30 °C. FESEM-EDX, FTIR and BET isotherm studies are done to characterize raw and fluoride treated biomass. Lagergren first order kinetic model and Freundlich isotherm model, are found to analyze best kinetic and equilibrium data, respectively. Adsorption capacity of DBM has been found to be 34.36 mg/g. The kinetics of fluoride removal have been well described by COMSOL Multiphysics.

GIS based evaluation of crop suitability for agricultural sustainability around Kolaghat thermal power plant, India.

Fly ash exhaust from Kolaghat thermal power plant, West Bengal, India,?? affects the areas within the radius of 3 - 4 km. Land information system indicated that surface texture within 4 km was silty loam and clay content increased with increase of distance. Soil pH was alkaline (7.58-8.01) in affected circles, whereas soil was acidic (5.95-6.41) in rest of block. Organic carbon (OC) is roving from 0.36 to 0.64% in the nearer circles which is lesser from others. The present Crop suitability analysis revealed that 96.98 % area was suitable (S1) for maize, sesame, jute, whereas these were cultivated in less than 1% of land. Flowers are the best suitable (S1) in 88.9 % but it was grown in 6.02 % area.? The present rice area within 4 km of KTPP is showing moderately suitable (S2) and S1 for the rest. Wheat is moderately suitable (S2) in the almost all the circles.? Cultivation of vegetable crops is limited in the affected circles while the highly suitable (S1) comprises 67.49 % for the remaining areas though it covered only 6.01 % of the block.? This evaluation precisely improves more than 300% from the earlier cropping intensity of 177.95 %. Suitability based land use allocation serves as stepping stone to promote agricultural sustainability. Geographic information system (GIS) model has been developed to assess site specific crop suitability for sustainable agricultural planning.

Attitudes and knowledge regarding referrals for bariatric surgery among Danish secondary healthcare providers: A national survey.

Bariatric surgery induces significant and sustained weight loss and subsequently reduces obesity-related comorbidities. However, only a small percentage of patients with severe obesity undergo bariatric surgery in Denmark. There is limited knowledge about the experiences with and possible reservations to bariatric surgery among secondary healthcare providers. The aim of this cross-sectional study was to investigate referral patterns and knowledge regarding the criteria for bariatric surgery among Danish secondary healthcare providers, treating obesity-related diseases. A questionnaire regarding experiences with and reservations to referring patients for consideration for bariatric surgery, along with thoughts to specific patient cases were sent to several specialists: endocrinologists, obstetricians and gynaecologists, orthopaedic surgeons and otorhinolaryngologists. Most questions required responses on a 5-point Likert scale and frequency distributions were calculated. A total of 345 (44%) specialists responded to the questionnaires. Good knowledge of the criteria for referral to bariatric surgery varied among the specialist from 6% to 68%. One of the main issues was a concern about the medical and surgical postoperative complications, which was a barrier to and influenced referral decisions. Furthermore, specialists were more likely to refer patients to bariatric surgery when patients requested this. Except for endocrinologists, the Danish secondary healthcare specialists interviewed have limited knowledge about bariatric surgery, which results in a reluctance in referring patients. Our results indicate that there is a need to improve knowledge among specialists, regarding the indications, criteria and outcomes for bariatric surgery to establish a more pro-active, specialist led approach to referrals.

A comparative study of removal of fluoride from contaminated water using shale collected from different coal mines in India.

Low-cost water defluoridation technique is one of the most important issues throughout the world. In the present study, shale, a coal mine waste, is employed as novel and low-cost adsorbent to abate fluoride from simulated solution. Shale samples were collected from Mahabir colliery (MBS) and Sonepur Bazari colliery (SBS) of Raniganj coalfield in West Bengal, India, and used to remove fluoride. To increase the adsorption efficiency, shale samples were heat activated at a higher temperature and samples obtained at 550 °C are denoted as heat-activated Mahabir colliery shale (HAMBS550) and heat-activated Sonepur Bazari colliery shale (HASBS550), respectively. To prove the fluoride adsorption onto different shale samples and ascertain its mechanism, natural shale samples, heat-activated shale samples, and their fluoride-loaded forms were characterized using scanning electron microscopy, energy dispersive X-ray analysis, X-ray diffraction study, and Fourier transform infrared spectroscopy. The effect of different parameters such as pH, adsorbent dose, size of particles, and initial concentration of fluoride was investigated during fluoride removal in a batch contactor. Lower pH shows better adsorption in batch study, but it is acidic in nature and not suitable for direct consumption. However, increase of pH of the solution from 3.2 to 6.8 and 7.2 during fluoride removal process with HAMBS550 and HASBS550, respectively, confirms the applicability of the treated water for domestic purposes. HAMBS550 and HASBS550 show maximum removal of 88.3 and 88.5 %, respectively, at initial fluoride concentration of 10 mg/L, pH 3, and adsorbent dose of 70 g/L.