Microplastics (<5 mm) have become an environmental hazard to natural ecosystems and humanity due to their ubiquitous presence in the environment, and possess detrimental effects on aquatic organisms. ...Sampling, extraction, and detection of microplastics from sediments, surface water, and biota are quite complex and challenging. Rigorous research on the abundance and distribution of microplastics in terrestrial and aquatic ecosystems is primarily attributed to instinctive anthropogenic actions like land-based activities. Although, the fate and transport of microplastics in the environment are uncertain. Therefore, this paper reviews current research progress on the occurrence and distribution of microplastic pollution in the riverine ecosystem. Detailed potential sources, sampling techniques, and experimental design have been discussed, along with the classification and detection of microplastics in the riverine sediment and surface water. Microplastic ingestion through riverine species is also discussed systematically which emphasizes the extraction of microplastics from different body parts of the organism. Different types of polymeric microplastic have been observed in rivers, for instance, PS, PE, PP, PA, PET, PVC, PDPE, LPDE, nylon, acrylic, etc. using spectroscopy. Fragments, foams, pellets, films, fibers and microbeads are common shapes of microplastic which are abundant in the riverine ecosystem. The ingestion and ecological concern of microplastics, along with adsorption mechanisms of toxic contaminants, such as heavy metals, organic pollutants, nutrients, antibiotics, etc. onto microplastics surface and their exposure to aquatic organisms have also been discussed. Microplastic pollution in riverine ecosystems is under global change stress due to ecotoxicological and geochemical consequences. Further, detailed policies intervention for plastics and microplastics mitigation have been focused which delineate for application of science and policy together with scientific evidence. Lastly, scientific knowledge gaps and future research prospective on microplastic pollution have been given, along with suggestions and policy recommendations.
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•Major sources of microplastic pollution in rivers are urbanization and anthropogenic activities.•Riverine fishes are the most exposed freshwater species to microplastics.•Heavy metals, organic contaminants, nutrients, and antibiotics are adsorbed onto microplastics, increases ecotoxicity.•Microplastics interaction with aquatic organisms leads to ecological damage in the riverine ecosystem.•Policies for the plastic ban are required to optimize plastic production and less exposure to the natural environment.
Soil erosion is a pressing environmental issue with significant agricultural productivity and ecosystem stability implications. In recent years, biochar, a carbon-rich product of biomass pyrolysis, ...has emerged as a promising soil amendment tool for erosion control due to its ability to improve soil quality and stability. This review paper aims to comprehensively analyze the effectiveness of biochar role in mitigation of soil erosion and sustainable land management practices. By examining a wide range of research studies, this paper elucidates the impact of biochar on key soil erosion parameters as it directly affects the soil structure, water-holding capacity, and nutrient retention. The paper discusses how biochar interacts with soil particles and aggregates to enhance their stability and resistance to erosive forces. It also assesses the influence of biochar properties, such as feedstock type, pyrolysis temperature, and application rate, on its erosion control efficacy. Furthermore, this review explores the role of biochar in promoting plant growth and root development, thereby reinforcing the vegetation cover and further reducing erosion susceptibility. Finally, an outline of potential challenges and opportunities for the widespread adoption of biochar-based erosion control strategies in different agricultural and environmental contexts is presented. Overall, this review provides valuable insights into the multifacet role of biochar in sustainable soil management and offers recommendations for future research directions on direct and indirect application on soil erosion control.
Extraction and quantification of nano- and microplastics from sediments and soils is challenging. Although no standard method has been established so far, flotation is commonly used to separate ...plastic from mineral material. The objective of this study was to test the efficiency of flotation for the extraction of nano- and microplastics from biosolids and soil. We spiked biosolids and soil samples with polystyrene nano- and microbeads (0.05, 1.0, 2.6, 4.8, and 100 μm diameter). Different extraction methods (w/ and w/o H2O2 digestion) were tested, and plastic beads were separated from mineral particles by flotation in a ZnCl2 solution. Plastic particles were quantified by UV-Vis spectrometry and gravimetrically. While large beads (100 μm) could be quantitatively extracted (∼100%) from both biosolids and soils, smaller beads had low extraction efficiencies (ranging from 5 to 80%, with an average of 20%). Except for the 100 μm beads, oxidation with H2O2 negatively impacted the extraction efficiencies. For the soil, extraction with water only, followed by flotation in a ZnCl2 solution, resulted in relatively high extraction efficiencies (>75%) for beads larger than 1 μm, but low efficiencies (<30%) for the 0.05 and 1.0 μm beads. Our results indicate that while flotation generally works to separate plastic nano- and microbeads in a solution, the challenge is to quantitatively extract nano- and microbeads from a biosolids or soil matrix. Samples high in organic matter content require removal of the organic matter, but the common method of H2O2 oxidation leads to poor extraction efficiencies for nano- and microbeads.
Nephropathy is a major microvascular complication of diabetes mellitus and often leads to terminal renal failure in addition to contributing significantly to cardiovascular morbidity and mortality. ...Despites continuous advances, the pathogenesis of diabetic nephropathy remains poorly understood. Recent studies have underscored the significance of structural and functional changes in podocytes in the development and progression of diabetic nephropathy. The role of podocytes in health and diabetic nephropathy and abnormalities including podocyte hypertrophy, effacement, and apoptosis, and a detailed discussion on the role played by the Wnt-β-catenin signaling pathway in podocyte injury and dysfunction are the focus of this review. In addition, the role played by Wnt signaling in mediating the effects of known therapeutic strategies for diabetic nephropathy is also discussed.
Sustainable Development Goals were established by the United Nations General Assembly to ensure that everyone has access to clean, affordable, and sustainable energy. Third-generation biodiesel ...derived from algae sources can be a feasible option in tackling climate change caused by fossil fuels as it has no impact on the human food supply chain. In this paper, the combustion and emission characteristics of Azolla Pinnata oil biodiesel-diesel blends are investigated. The multi-objective response surface methodology (MORSM) with Box–Behnken design is employed to decrease the number of trials to conserve finite resources in terms of human labor, time, and cost. MORSM was used in this study to investigate the interaction, model prediction, and optimization of the operating parameters of algae biodiesel-powered diesel engines to obtain the best performance with the least emission. For engine output prediction, a prognostic model is developed. Engine operating parameters are optimized using the desirability technique, with the best efficiency and lowest emission as the criteria. The results show Theil’s uncertainty for the model’s predictive capability (Theil’s U2) to be between 0.0449 and 0.1804. The Nash–Sutcliffe efficiency is validated to be excellent between 0.965 and 0.9988, whilst the mean absolute percentage deviation is less than 4.4%. The optimized engine operating conditions achieved are 81.2% of engine load, 17.5 of compression ratio, and 10% of biodiesel blending ratio. The proposed MORSM-based technique’s dependability and robustness validate the experimental methods.
Microplastic disposal into riverine ecosystems is an emergent ecological hazard that mainly originated from land-based sources. This paper presents a comprehensive review on physical processes ...involved in microplastics transport in riverine ecosystems. Microplastic transport is governed by physical characteristics (e.g., plastic particle density, shape, and size) and hydrodynamics (e.g., laminar and turbulent flow conditions). High-density microplastics are likely to prevail near riverbeds, whereas low-density particles float over river surfaces. Microplastic transport occurs either due to gravity-driven (vertical transport) or settling (horizontal transport) in river ecosystems. Microplastics are subjected to various natural phenomena such as suspension, deposition, detachment, resuspension, and translocation during transport processes. Limited information is available on settling and rising velocities for various polymeric plastic particles. Therefore, this paper highlights how appropriately empirical transport models explain vertical and horizontal distribution of microplastic in riverine ecosystems. Microplastics interact, and thus feedback loops within the environment govern their fate, particularly as these ecosystems are under increasing biodiversity loss and climate change threat. This review provides outlines for fate and transport of microplastics in riverine ecosystems, which will help scientists, policymakers, and stakeholders in better monitoring and mitigating microplastics pollution.
The intense increase in air pollution caused by vehicular emissions is one of the main causes of changing weather patterns and deteriorating health conditions. Furthermore, renewable energy sources, ...such as solar, wind, and biofuels, suffer from weather and supply chain-related uncertainties. The electric vehicles’ powered energy, stored in a battery, offers an attractive option to overcome emissions and uncertainties to a certain extent. The development and implementation of cutting-edge electric vehicles (EVs) with long driving ranges, safety, and higher reliability have been identified as critical to decarbonizing the transportation sector. Nonetheless, capacity deteriorating with time and usage, environmental degradation factors, and end-of-life repurposing pose significant challenges to the usage of lithium-ion batteries. In this aspect, determining a battery’s remaining usable life (RUL) establishes its efficacy. It also aids in the testing and development of various EV upgrades by identifying factors that will increase and improve their efficiency. Several nonlinear and complicated parameters are involved in the process. Machine learning (ML) methodologies have proven to be a promising tool for optimizing and modeling engineering challenges in this domain (non-linearity and complexity). In contrast to the scalability and temporal limits of battery degeneration, ML techniques provide a non-invasive solution with excellent accuracy and minimal processing. Based on recent research, this study presents an objective and comprehensive evaluation of these challenges. RUL estimations are explained in detail, including examples of its approach and applicability. Furthermore, many ML techniques for RUL evaluation are thoroughly and individually studied. Finally, an application-focused overview is offered, emphasizing the advantages in terms of efficiency and accuracy.
Diabetic nephropathy (DN) is currently well established as the most common cause of end-stage renal disease in most parts of the world. Notwithstanding the expanding basic and clinical research in ...this field, the pathogenesis remains far from clear and hence the treatment of DN remains suboptimal. There is a critical need for the development of newer therapeutic strategies including alternative and complementary therapies. One of the natural products that was extensively studied in cancer and other chronic disease states such as diabetes is curcumin, an active ingredient in turmeric, a spice extensively used in India. In this manuscript, we present a critical review of the experimental and clinical evidence that supports the use of curcumin and its analogs in DN as well as the various proposed mechanisms for its biological actions in health and disease states.
The present investigation focuses on the fabrication of Copper-High Entropy Alloy (HEA) surface Metal Matrix Composite (MMC) using the solid-state Friction Stir Process (FSP) and the characterization ...of wear characteristics. Higher hardness values at the level of 770HV were the cornerstone in its selection, in addition to identifying several appropriate considerations for combining the AlCoCrCuFe HEA in Cu-HEA surface MMCs. Because of the combination of FSP and HEA, the produced composite had a fine microstructure and increased hardness. The wear test is carried out using pin-on-disc equipment for all conceivable parameter combinations to thoroughly analyze wear qualities, with velocity, load, as well as sliding distance chosen as input parameters. The wear rate decreases dramatically with HEA additions and rises with sliding velocity, load, and sliding distance. The impact of HEA addition on the Coefficient of Friction (CoF) during a dry sliding wear test is opposed to its influence on wear rate. The wear parameters such as load, sliding speed, and sliding distance possess a positive correlation with the wear rate and a negative correlation with a coefficient of friction. The applied load has a severe effect on wear rate and CoF when compared to other wear parameters considered. Scanning Electron Microscope (SEM) micrographs of the worn surface were utilized to analyze the wear process, which clearly showed that the copper's wear resistance improved with the addition of HEA.
The influence of humans on the environment is growing drastically and is pervasive. If this trend continues for a longer time, it can cost humankind, social and economic challenges. Keeping this ...situation in mind, renewable energy has paved the way as our saviour. This shift will not only help in reducing pollution but will also provide immense opportunities for the youth to work. This work discusses about various waste management strategies and discusses the pyrolysis process in details. Simulations were done keeping pyrolysis as the base process and by varying parameters like feeds and reactor materials. Different feeds were chosen like Low-Density Polyethylene (LDPE), wheat straw, pinewood, and a mixture of Polystyrene (PS), Polyethylene (PE), and Polypropylene (PP). Different reactor materials were considered namely, stainless steel AISI 202, AISI 302, AISI 304, and AISI 405. AISI stands for American Iron and Steel Institute. AISI is used to signify some standard grades of alloy steel bars. Thermal stress and thermal strain values and temperature contours were obtained using simulation software called Fusion 360. These values were plotted against temperature using graphing software called Origin. It was observed that these values increased with increasing temperature. LDPE got the lowest values for stress and stainless steel AISI 304 came out to be the most feasible material for pyrolysis reactor having the ability to withstand high thermal stresses. RSM was effectively used to generate a robust prognostic model with high efficiency, R
(0.9924-0.9931), and low RMSE (0.236 to 0.347). Optimization based on desirability identified the operating parameters as 354 °C temperature and LDPE feedstock. The best thermal stress and strain responses at these ideal parameters were 1719.67 MPa and 0.0095, respectively.
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