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The present study elaborates the electrocoagulation process for the removal of nitrates from synthetic and real groundwater. Electrocoagulation treatment has a positive effect on the quality of groundwater in general and the removal of nitrate in particular, which is one of the most potent pollutants found in groundwater. Moreover, it is supposed that nitrate removal mechanisms are likely to be dependent on operational parameters like applied current, electrode material, initial concentration of nitrates, and pH of the solution, etc. Therefore, in the present study various process parameters have been optimised in terms of nitrate removal efficiency. Experiments were performed using batch process at different initial concentration of nitrates (100–500 mg/L), pH (6.0–12), stirring speed (100–500 rpm), inter-electrode distance (0.5–2 cm) and electrolysis time (30–180 min). Further, the effect of co-existing ions using KNO3, Ca(NO3)2 and Mg(NO3)2 in the presence of NaCl and Na2SO4 was investigated. Maximum 98%, Nitrate removal efficiency was obtained at inter-electrode distance 1 cm, agitation speed 300 rpm, electrolyte concentration of 1.1688 (g/L) NaCl, current 1.5 A and time 180 min for initial nitrate concentration of 100 (mg/L). Isotherm and kinetics models have been studied and it was observed from the present investigation that the process follows pseudo-second-order kinetics. The Freundlich isotherm model simulations match satisfactorily with the experimental observations. Further, optimised parameters were used to remove nitrates from real groundwater and 92.5% removal efficiency was attained. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag-NPs) have emerged as potential antifungal agents due to their exceptional properties. These nanoparticles can be synthesised in the laboratory by using green synthetic methods. Hence, in the present study dark brown colour Ag-NPs have been synthesized from 0.01 mM AgNO3 using Azadirachta indica leaf extract as a reducing agent and characterised via different spectroscopic and microscopic techniques. The average particle sizes of the synthesized Ag-NPs are found to be 36 nm and all the particles are mostly spherical in shape. These biosynthesized Ag-NPs effectively have mitigated the mycelial growth of F. oxysporum and F. moniliforme. However, the inhibition has been found better for F. oxysporum as compared to F. moniliforme. At 500 ppm concentration of Ag-NPs, the reductions in mycelial growth have been found to be 100 and 80% for F. oxysporum and F. moniliforme, respectively. So, it can be concluded from the study that Ag-NPs prepared from A. indica leaf extracts could be explored for developing fungicidal formulations. [ABSTRACT FROM AUTHOR]

Background & objectives: Female genital tuberculosis (FGTB) is an important variety of extrapulmonary TB causing significant morbidity, especially infertility, in developing countries like India. The aim of this study was to evaluate the laparoscopic findings of the FGTB. Methods: This was a cross-sectional study on 374 cases of diagnostic laparoscopy performed on FGTB cases with infertility. All patients underwent history taking and clinical examination and endometrial sampling/biopsy for acid-fast bacilli, microscopy, culture, PCR, GeneXpert (only last 167 cases) and histopathological evidence of epithelioid granuloma. Diagnostic laparoscopy was performed in all the cases to evaluate the findings of FGTB. Results: Mean age, parity, body mass index and duration of infertility were 27.5 yr, 0.29, 22.6 kg/m2 and 3.78 years, respectively. Primary infertility was found in 81 per cent and secondary infertility in 18.18 per cent of cases. Endometrial biopsy was positive for AFB microscopy in 4.8 per cent, culture in 6.4 per cent and epithelioid granuloma in 15.5 per cent. Positive peritoneal biopsy granuloma was seen in 5.88 per cent, PCR in 314 (83.95%) and GeneXpert in 31 (18.56%, out of last 167 cases) cases. Definite findings of FGTB were seen in 164 (43.86%) cases with beaded tubes (12.29%), tubercles (32.88%) and caseous nodules (14.96%). Probable findings of FGTB were seen in 210 (56.14%) cases with pelvic adhesions (23.52%), perihepatic adhesions (47.86%), shaggy areas (11.7%), pelvic adhesions (11.71%), encysted ascites (10.42%) and frozen pelvis in 3.7 per cent of cases. Interpretation & conclusions: The finding of this study suggests that laparoscopy is a useful modality to diagnose FGTB with a higher pickup rate of cases. Hence it should be included as a part of composite reference standard. [ABSTRACT FROM AUTHOR]

Mann–Kendall (MK) test is a non-parametric technique widely used for trend analysis in time series datasets. However, the datasets tend to be noisy which increases data variance and often results in false rejection of null hypothesis. The present study investigates use of spatial autocorrelation (i.e., contextual information) to address influence of noise in the MK test. By incorporating spatial autocorrelation, the false trend can be identified, while at the same time spatial autocorrelation provides support for strengthening the results. The contextual MK test (CMK) was used for analysing NO2 trend in the Northern Indian states of Punjab, Haryana, Delhi, Uttar Pradesh, Madhya Pradesh, and Rajasthan during paddy stubble burning, using TROPOspheric Monitoring Instrument total vertical column density data. The serial correlation in the datasets was removed using pre-whitening before running the CMK and conventional MK test. In year 2021, MK test identified 12.9% of the grid cells with monotonous increasing trend of NO2, which increased to 14.1% when CMK test was used. Similarly, cells with monotonous increasing NO2 trend in year 2020, were 8.7% and 9.5% using MK and CMK tests respectively. Thus, CMK test was able to identify more cells having a monotonous increasing trend of NO2 compared to the MK test, while at the same time the spurious trend could also be efficiently handled. Subsequently, using CMK test state-wise analysis of NO2 trend was also carried out. [ABSTRACT FROM AUTHOR]