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The coronavirus disease 2019 (COVID-19) pandemic, caused by the novel virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began in December 2019 in China and has led to a global public health emergency. Previously, it was known as 2019-nCoV and caused disease mainly through respiratory pathways. The COVID-19 outbreak is ranked third globally as the most highly pathogenic disease of the twenty-first century, after the outbreak of SARS-CoV and Middle East respiratory syndrome in 2002 and 2012, respectively. Clinical, laboratory, and diagnostic methodology have been demonstrated in some observational studies. No systematic reviews on COVID-19 have been published regarding the integration of COVID-19 outbreaks (monitoring, fate and treatment) with environmental and human health perspectives. Accordingly, this review systematically addresses environmental aspects of COVID-19 outbreak such as the origin of SARS-CoV-2, epidemiological characteristics, diagnostic methodology, treatment options and technological advancement for the prevention of COVID-19 outbreaks. Finally, we integrate COVID-19 outbreaks (monitoring, fate and treatment) with environmental and human health perspectives. We believe that this review will help to understand the SARS-CoV-2 outbreak as a multipurpose document, not only for the scientific community but also for global citizens. Countries should adopt emergency preparedness such as prepare human resources, infrastructure and facilities to treat severe COVID-19 as the virus spreads rapidly globally.

Irrigation forms one of the primary components of agriculture and food production. Due to outdated techniques in developing and underdeveloped countries, a huge volume of water is wasted in this process. In this article, we have devised a fuzzy rule-base irrigation controller prototype to put a check on this water wastage by providing an optimal irrigating environment for farming. The prototype smart automatic irrigation controller (SAIC) has two operational units, namely, wireless sensor unit (WSU) and wireless information processing unit (WIPU). The purpose of the WSU is to measure weather and soil conditions and calculate the actual water loss due to evapotranspiration. The WIPU processes this calculated value and performs the necessary control action to regulate the actuators supplying the right amount of water to the farm. An exhaustive rule-base combination model is stacked in the lookup table for decision making. The prototype model is first simulated and then validated in the field for checking the performance efficiency. The simulated results showed capabilities to compensate for water loss by almost 100%. The controller achieved a 27% reduction in water usage and a 40% increase in crop yield. The prototype is connected to a cloud server for data repository and remote access and control. The device is efficient, low cost, and user friendly so that the end-users can it with ease and comfort. The model is innovative and unique in the sense that it can the irrigation scheduling for all types of crops, across all climatic conditions for all soil types upon feeding the proper soil–crop–growth stage combinations in the inference engine.

Present work evaluated the possible impact of choline on metabolic enzymes of cultured fish species into a semi-intensive pond culture system, reared with Catla catla (catla), Labeo rohita (rahu), Clarias batracus (magur) and Anabas testudineus (climbing perch) for 90 days in two seasons. Choline was added directly into the pond water periodically throughout the experimental tenure. The water quality parameters of each experimental pond were monitored and were analyzed in 15 days interval throughout the experimental tenure in both the seasons. Results were compared with treatment as choline-fed and control as non-choline-fed conditions during breeding (June–Aug.) and dry (Nov.–Jan.) seasons. The metabolic enzymes, viz., LDH (Lactate dehydrogenase), MDH (Malate dehydrogenase), and G6PDH (Glucose-6-phosphate dehydrogenase) activities in the muscle, liver, and AchE (Acetylcholine esterase) activity in the brain and muscle revealed maximum significantly (p

Polyaromatic compounds are the major, widespread contaminants in the aquatic environment. However, the adverse impacts of these compounds on blood pathophysiology (hematological profiling and serum biochemical responses) are poorly understood. As a consequence, this study was intended to evaluate the toxic effects of naphthalene, one of the polycyclic aromatic hydrocarbons, on the blood pathophysiology of Anabas testudineus using multiple end-point biomarker approach. A. testudineus was exposed to short-term (1 and 5 d) and long-term (10, 15, and 21 d) naphthalene concentrations, that is, T1 (0.71 mg/L indicates 25% of LC50) and T2 (1.42 mg/L indicates 50% of LC50 value). The results disclosed significant decrease in red blood cells, hemoglobin (Hb), packed cell volume, and platelet levels, while other blood parameters, namely, white blood cells, percent lymphocyte, mean cell volume, mean corpuscular Hb, and mean corpuscular Hb concentration showed enhanced levels under naphthalene intoxication. Results were more detrimental under T2 concentration. Cholesterol, glucose, calcium, high-density lipoprotein, and low-density lipoprotein levels gradually increased throughout the different exposure periods under T1 and T2 concentrations, while the triglyceride level gradually decreased during exposure periods. Finally, integrated biomarker responses (IBR) analysis indicated that serum biochemical parameters are more powerful than hematological parameters for determining the naphthalene-induced fish health status. Additionally, the IBR study clearly identified that long-term (>5 d) exposure was more harmful than short-term (

The present study deals with the impact of choline chloride supplementation, applied directly into the pond water in a semi-intensive farm culture system for 90 d on two Indian Major Carps (IMCs) (Catla catla, Labeo rohita) and two air-breathing teleostean fishes (Anabas testudineus, Clarias batracus).The experiment was conducted in two seasons (breeding and dry) under choline (treated) and non-choline (control) exposure. Biochemical parameters, viz., PRO (total protein) content gained maximum significantly (p< 0.01) in treated-breeding with the lowest in control-dry in intestine, liver, muscle, brain. IMCs showed significant (p< 0.01) increased amylase activity in the liver and intestine in treated-dry and treatment-breeding conditions, while liver amylase activity in both the seasons increased manifolds significantly (p< 0.01) in air-breathing fishes, showing a sharp decline only in the intestine. Protease and lipase activity in the intestine and liver of choline-fed fishes disclosed declining trend in the breeding season significantly (p< 0.01), but treated (choline-fed) IMCs under dry revealed the significant (p< 0.01) increasing and decreasing trend of protease and lipase activity respectively; the reverse trend at dry season was found in air-breathing fishes under choline-fed condition. ALP (alkaline phosphatase) in intestine indicated significant (p< 0.01) lowest activity in treatment-breeding, highest in treatment-dry. This study explored the higher activity towards total protein generation, especially muscle; higher carbohydrate digestion; elevated lipid digestion in choline-fed fishes. So, the fishes from this farm-based pisciculture system are healthy and its yield can be prescribed as a rich source of quality fish food for human health.

The productivity of soil largely depends on the optimum conditions of farmingincluding the water quality. With the proper pH values of the water-soil moisture maintained during the time of farming leads to absorption of right amount of minerals to the plant body which increases the productivity of the crop. Under normal practice, it is often found that the pH value of the irrigational water overlooked and hence the optimum conditions are maintained. In this article, a noble approach is taken to regulate the valve response so that this pH mismatch between the supplied water and soil can be rectified and the most suitable value can be preserved. While with the use of Penman-Monteith (PM) method, the water loss due to evapotranspiration is determined and water valves are operated to supply the necessary volume to eliminate the crop-water stress, an exhaustive fuzzy rule-base model is developed to control the opening and closing of the valves based of the pH value of the supplied water to maintain the optimal values. On evaluation of the designed model, it is seen that the PM model is successful is determining the water loss and the on encountering a surge in the acidic levels of the supplied water, the valve constricts to slow down the water flow and it inflates while the water is alkaline is nature. Thus the objective of the model is properly served and significant results are obtained.

The present study focuses on adsorption of chromium (trivalent and hexavalent) by using sewage-produced biochar as well as reduction of the produced sewage. Biochar is produced from municipal sewage to examine the capability of two biochars i.e., prepared at 450°C SWB450 and 550°C SWB550 to sorb trivalent chromium [Cr(III)] and hexavalent chromium [Cr(VI)] using batch experiments. Brunauer Emmett Teller (BET) data indicated higher surface area of SWB550 compared to SWB450, which supports the field emission scanning electron microscope (FESEM) results. 4 g L−1 biochar doses emerged as the optimum for Cr(III) and Cr(VI) removal for both biochars at pH 5.0. Performance of SWB550 was 92.9% for Cr(III) and

The current study is aimed to assess the ecotoxicological effects of toxic metals and seasonal shift of the physicochemical characteristics of soil in an endogeic earthworm Metaphire posthuma of industrially contaminated soil of Calcutta leather complex. The accumulation of cadmium, chromium, lead and mercury was quantitated in whole earthworms and coelomocytes. The accumulation of metals was derived to be high in the coelomocytes than whole earthworms. Morphofunctional shift in coelomocytes indicated a high level of metal toxicity in soil inhabitants. The shift in differential coelomocyte count and cellular damage including intense cytoplasmic vacuolation and membrane blebbing of coelomocytes of M. posthuma of contaminated soil were suggestive to a state of immunocompromisation in the same species. Shift in the generation of nitric oxide and activity of inducible nitric oxide synthase indicated a possible immunosuppression in earthworm. Depletion in the acetylcholinesterase activity of coelomocytes indicated neurotoxicity of metals leached from the dumped wastes in Calcutta leather complex. Integrated biomarker response based analysis was carried out to assess the biomarker potential of experimental endpoints of M. posthuma to monitor metal toxicity in soil.

The present study was designed to assess the adverse effects of the agrochemical Almix on comparative basis in gill, liver and kidney of Heteropneustes fossilis through histological and ultrastructural observations under field (8 g/acre) and laboratory (66.67 mg/L) conditions. Exposure duration of both experiments was 30 days. Gill showed atrophy in secondary lamellae, hypertrophied gill epithelium, damage in chloride and pillar cells, and detachment of chloride cells from gill epithelium under laboratory condition, but hypertrophy in gill epithelium and fusion in secondary lamellae were seen under field condition. In gill, scanning electron microscopy (SEM) showed fragmentation in microridges, hyper-secretion of mucus and loss of normal array in microridges, while transmission electron microscopy (TEM) displayed dilated mitochondria and rough endoplasmic reticulum (RER), abnormal sized vacuolation in chloride cells under laboratory condition. In liver, hypertrophied and pyknotic nuclei, disarrangement of hepatic cords, and cytoplasmic vacuolation were prominent under laboratory study but in field condition the liver showed little alterations. TEM study showed severe degeneration in RER and mitochondria and cytoplasmic vacuolation under laboratory condition but dilated mitochondria were prominent in field observation. Kidney showed severe nephropathic effects including degenerative changes in proximal and distal convolute tubule, damage in glomerulus under light microscopy, while deformity in nucleus, fragmentation in RER, severe vacuolation and necrosis in kidney were prominent under TEM study. The results clearly demonstrated that responses were more prominent in laboratory than field study. Thus the responses displayed by different tissues of concerned fish species exposed to Almix could be considered as indications of herbicide toxicity in aquatic ecosystem.

In this article, a stability analysis on an inverted pendulum system has been approached using a fractional order PID controller and a fractional order-based model reference adaptive controller. A modified MIT rule provides an extra degree of freedom, unlike an MIT rule of MRAC controllers to stablize the pendulum angle of the inverted pendulum system which is highly unstable in nature. Here, to analyze better stability performance of the inverted pendulum over the fractional order MIT rule of MRAC controller optimal fractional order, a PID controller has been approached and FMINCON numerical optimization algorithm has been chosen to optimize the fractional order PID controller using ITSE as a scaler objective function. Next, the behaviourial characteristics of the pendulum have been compared between the FMINCON-based FOPID controllers and the fractional order MIT rule of the MRAC controller to show robust performance using an optimal FOPID controller with respect to performance indices increases time, settling time, followed by errors ISE, IAE, ITSE.

Present work compared the toxicological responses of A. testudineus (Bloch) to anthracene exposure after treatment with two concentrations i.e., 25% (0.0075 mg/l) and 50% (0.015 mg/l) of LC50 value (0.030 mg/l) for different exposure periods of 1, 5, 10, 15 and 21 day(s). An intensive comparison of the effects was made based on haematological and biochemical parameters of blood. Haematological responses revealed significant increase in some blood parameters, viz., WBC, %LYM, MCV, MCH and MCHC but RBC, Hb, PCV and PLT showed decreasing trends. Biochemical responses like CHOLES, PRO, ALB, Trig showed enhanced pattern in the initial exposure of day one then reduced gradually but GLU, GPT, Ca, ALP, HDL, and LDL showed reverse pattern. Additionally, integrated biomarker responses (IBR) indicated that the biochemical parameters are more useful in determining the anthracene stress on fish health than the haematological parameters. Overall findings of this study suggested that the IBR analysis is a useful tool in monitoring quantitative (dose-specific) as well as qualitative (exposure-specific) responses to toxicological effects of anthracene exposure on fish health. Keywords: Anthracene, Haematological and biochemical parameters, IBR

Although nationwide lockdown was imposed in India amid COVID-19 outbreak since March 24, 2020, the COVID-19 infection is increasing day-by-day. India became world’s second most affected country. By 13th May, 2021 India recorded 23,703,665 cases with 258,351 deaths and 19,734,823 recovered cases. Here, we described the possibility of COVID-19 reactivation and disease recurrence through horizontal transmission in individuals after recovery from COVID-19 infection, in particularly in India. Additionally, the study will demonstrate how COVID-19 reactivation/reinfection could play a dominant role in disease burden. WHO (World Health Organization) recommended two times RT-PCR swabs test in discharged patients after clinical recovery from COVID-19 infection to confirm the disease recurrence globally. As per global data, the virus changing the molecular configuration and fluctuating time-by-time mainly because of viral load, occurrence of false-negative results at molecular test, inefficiency of sampling operator, even sampling procedure etc [1]. Recently, Ye et al. [2] mentioned that about 9% reactivation in COVID-19 patients occurred after discharge from the hospital. Further, they demonstrated host status, virologic features and steroid-induced immunosuppression as prime risk factor for the incidence of COVID-19 reactivation. Lombardi et al. [3] recommended domicile quarantine of 14 days after hospital discharge for safety purposes, but clear information about infectiousness time and virus shedding duration is still lacking. Rothe et al. [4] demonstrated that both pre-symptomatic and asymptomatic carriers might be responsible for COVID-19 reactivation, while Chen et al. [1] reported that convalescent might transmit the virus for further re-infection. Therefore, further investigations are needed to define appropriate quarantine period, to avoid transmission. Recently, COVID-19 reinfection among COVID-19 patients has dazed scientific community, but uncertainty exists whether this second wave is due to reinfection or new virus strain. Till now 64 cases of reinfection has been reported globally in individuals, recovered from COVID-19 with an estimate ranging from 7.35 to 21.4% [5]. Immunological analysis in this regard plays an important role to determine viral reinfection properly as traditional diagnostic methods like RT-qPCR, high through put sequencing, CT scan; blood sample analysis has some limitations. Additionally, different swab sample source, improper sampling, and variable sensitivity/specificity of nucleic acid tests can lead to false negative results implying disease persistence rather than recurrence. Generally, immunoglobulins alone are not enough for long-term immunity. Evidences showed that virus specific CD4+ T cells and CD8+ T cells plays a crucial role in long-term COVID-19 reactivation due to their persistency up to 6 years after SARS-CoV-1 virus infection [6]. Accordingly, Zhang et al. [7] observed lower concentrations of monocyte ACE2 (Angiotensin Converting Enzyme 2) in COVID-19 patients than healthy individuals, which necessitate further study to distinguish between reinfection and new infection. Further, the COVID-19 reactivation duration after first infection may vary between different virus clades of SARS-CoV-2 virus (e.g., A2a, B1), resulting distinct virulence as well. Accordingly, the nature of protective Neutralizing Antibodies (NAbs) varies for different strains and this indicated that NAbs of primary infection are not able to protect re-infection by other strains, resulting lower concentrations of NAbs during reinfection [6]. More recently, virus latency period is considered as potential factor to determine virus reactivation. Wang et al. [8] observed viral latency period 24 days for reinfection. In another study, Ye et al. [2] reported maximum latency period 17 days among 5 patients, but reactivation characteristics were not properly demarcated. They opined that virus is getting reactivated from a latent stage to a lytic stage with similar symptomatic manifestations. Additionally, SARSCoV- 2 virus can survive and replicate in neuronal cell lines [9], which indicated that there is possibility of reactivation through neuroinvasion of virus at later stage. In India, till now, three re-infection cases, one in Ahmedabad and two in Mumbai were brought under ICMR scanner, ICMR Director General Prof. Balram Bhargava said. Tillett et al. [10] demonstrated that individuals recovered from SARSCoV- 2 may not guarantee future immunity and second infection, if happens, was more severe with higher clinical symptoms than the first attack, the report says [10]. Whether the criteria to define a re-infection case is 90 days or 100 days, WHO is still not decided yet the cut-off point, says ICMR Director General Prof. Balram Bharagava. Further, Prof. Balram Bharagava demonstrated that India is considering cut-off about 100 day. But, till now ICMR did not revealed any data regarding those re-infected persons. Viral shedding is another potentially undetermined factor, which might cause reactivation or disease transmission from an apparently recovered individual or asymptomatic individual to healthy people [11]. Generally, viral shedding begins 2-3 days before symptoms appearance and it happens through non-respiratory or non-classical tract routes such as fecal-oral route, tears and conjunctival secretions etc. Virus remains unrecognized in all these non-respiratory or nonclassical routes during patient’s discharge, who are tested negative (nasopharyngeal RT-qPCR). But there is possibility of containing highly active viral titers in non-classical transmission sites of recovered patients, indicating that they not only reactivate themselves but also have capability to spread further infection. Accordingly, India should adopt more stringent public health emergency strategy along with exiting practices on urgent basis. Consequently, further research is also required simultaneously to fight the recurrence of COVID-19 symptoms in India. In particularly, infected persons should strictly be discharged after two consecutive RT-qPCR negative results of swab samples from various sources. Further, if possible, they should be monitored during post-discharge domiciliary quarantine period for 14 days followed by one additional RT-qPCR again. Finally, more precious policy should be adopted to stop the further spreading of COVID-19 infection in human population and need regularized monitoring of positive number of COVID-19 cases and death. In conclusion, considering the abovementioned facts, still there remains some unanswered questions: Are asymptomatic individuals more likely to spread the disease? Is proper treatment removes the virus completely from the system? Are the patients gained immunity for rest of their life? To address these facts, need immediate further study to prevent the COVID-19 infection vis-a-vis its reactivation.

In chemical engineering science, controlling temperature using nonlinear system is a very important task and continuous stirred tank reactor (CSTR) acts as a center of chemical process to control temperature at plant. In this work, to control temperature, IOPID and FOPID controllers have been tested on CSTR nonlinear model and simulation study has been performed. Fractional-order PID controller has been designed using RL fractional calculus method and plays advanced role using two degree of freedoms. PSO optimization algorithm has been used to optimize the parameters of controllers selecting ITAE as single objective function. Now, to stabilize the heat at satisfactory level, internal model control (IMC)-based FOPID controller followed by a novel technique on set point weighted-based IMC-FOPID has been approached to filter the performance of the system comparing with other controllers in simulation.

Biochemical Oxygen Demand (BOD), representing the biodegradable organic load in water, is a prime parameter to assess water quality. Estimation of biochemical oxygen demand requires prolonged incubation of water samples. Thus, it is a time-consuming as well as energy-consuming process. Therefore, it is not possible to respond rapidly for mitigation if the BOD level goes beyond the permissible limit. In this study on River Damodar, the BOD value was predicted from electrical conductivity (EC), turbidity and chloride, using Artificial Neural Network (ANN)-based empirical model. Since predictor parameters of these models are measurable rapidly, the BOD value can also be predicted quickly. As all the predictor parameters are highly correlated (correlation coefficient: 0.9 or more) with BOD, the models are valid for prediction of BOD. Additionally, for further validation of the models, a portion of field data (20%) was used for model testing. As the model predictions are close to the actual values (r = 0.98, MAE = 0.43, RMSE = 0.57), the model, developed in this study, can be considered as successful in BOD prediction.

Present investigation has made an attempt to assess the variations in physicochemical status of two urban ponds (constructed boundary: Pond A and natural boundary: Pond B) of Chandannagar and also established the variations in the diversity of macrophytes and zooplankton of the study areas during winter (Nov–Dec, 2017). Limnological parameters recorded from two spots collected in three phases, such as temperature, pH, transparency, conductivity, DO, BOD, total dissolved solids (TDS), total suspended solids (TSS), total alkalinity, total hardness and chloride, were evaluated. From this observation, it is reported that there are marked variations in different water quality parameters of two urban ponds during the study period. The value of water temperature in Pond A and B was 22.0 and 21.3 °C, respectively. pH value (7.9) was highest in Pond B. Pond B water was more turbid than Pond A. The highest values of other parameters like conductivity (218.50 µS/cm) DO (8.47 mg/l), BOD (5.69 mg/l), TDS (135.19 mg/l), TSS (67.60 mg/l), total alkalinity (181.15 mg/l), total hardness (145.66 mg/l) and chloride (58.94 mg/l) were found in case of Pond B. Maximum macrophytic vegetations were found in Pond B in comparison with Pond A. The study of the zooplankton community reveals that the maximum occurrence of rotifers in Pond B indicates pollution status.

This work was aimed to investigate the adverse impacts of Excel Mera 71 on Anabas testudineus, Heteropneustes fossilis and Oreochromis niloticus under laboratory (17.2 mg/L) and field (750 g/acre) conditions based on multiple-level integrated biomarker responses. Haematological parameters were influenced significantly and showed species specificity after Excel Mera 71 exposure under both the conditions. Physiological indices (hepato-somatic index and condition factor) showed higher values; however, hepato-somatic index induced significantly under both the conditions (p H. fossilis > A. testudineus), while total nuclear abnormalities under field showed the order as: H. fossilis (0.49 ± 0.08) > A. testudineus (0.46 ± 0.10) > O. niloticus (0.27 ± 0.05). Moreover, multi-level integrated biomarker responses displayed responses as: O. niloticus (6.97 fold) > H. fossilis (4.01 fold) > A. testudineus (2.33 fold) in laboratory; however, under field condition, responses were totally different [A. testudineus–H. fossilis (3.98 fold) > O. niloticus (3.01 fold)]. Additionally, glyphosate concentration was significantly correlated with several multi-level biomarker responses (p

This study evaluated the acute toxicity and oxidative stress responses to sodium fluoride (NaF) exposure in tadpoles of the skittering frog, Euphlyctis cyanophlyctis (Schneider 1799). The 96 h LC50 value was found to be 647 mg/L. Biochemical tests were conducted at 10%, 20%, 30%, 40%, 50%, 60%, 70% and 80% of the 96 h LC50 dose. Cholinesterase (ChE) activity was unaffected. Lipid peroxidation levels significantly increased (p

Although a nationwide lockdown was imposed in India amid COVID-19 outbreak since March 24, 2020, the COVID-19 infection is increasing day-by-day. Till June 10, 2021 India has recorded 29,182,072 COVID cases and 359,695 deaths. A number of factors help to influence COVID-19 transmission rate and prevalence. Accordingly, the present study intended to integrate the climatic parameters, namely ambient air temperature (AT) and relative humidity (H) with population mass (PM) to determine their influence for rapid transmission of COVID-19 in India. The sensibility of AT, H and PM parameters on COVID-19 transmission was investigated based on receiver operating characteristics (ROC) classification model. The results depicted that AT and H models have very low sensibility (i.e., lower area under curve value 0.26 and 0.37, respectively compared with AUC value 0.5) to induce virus transmission and discrimination between infected people and healthy ones. Contrarily, PM model is highly sensitive (AUC value is 0.912, greater than AUC value 0.5) towards COVID-19 transmission and discrimination between infected people and healthy ones and approximate population of 2.25 million must impose like social distancing, personal hygiene, etc. as strategic management policy. Therefore, it is predicted, India could be the next epicenter of COVID-19 outbreak because of its over population.

Present study was aimed to note the effects of glyphosate-based herbicide, Excel Mera 71 (17.20 mg/L) on digestive enzyme activity in teleostean fishes, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch) and their subsequent recovery responses under Liv.52 for a period of 30 days. Amylase activity was raised highly in intestine of A. testudineus (674.07%) and was lowest in liver of H. fossilis (180.14%). Lipase activity showed highest elevation in liver of H. fossilis (182.14%) and lowest in intestine of A. testudineus (70.77%). Highest elevation of protease activity was observed in intestine of H. fossilis (376.92%) but was lowest in liver of A. testudineus (138.46%). During depuration phase, these enzyme activities significantly came down towards the control value which indicated compensatory responses against herbicidal toxicosis. Therefore, it can also be inferred that these responses of A. testudineus and H. fossilis to Excel Mera 71 and Liv.52 exposures could be considered as biomarkers against herbicidal toxicosis in aquatic ecosystem, although it needs further studies on mechanistic pathway to investigate the detailed mechanism involved in recovery responses.