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Heavy metal-containing industrial effluents, such as Pb2+, Cd2+, and Cu2+, pose serious threats to the environment and public health since they are not biodegradable and can accumulate over time. Biochar, particularly sewage sludge-derived biochar (SSBC), has arisen as a promising and cost-effective material for heavy metal removal from wastewater due to its high adsorption capacity, large surface area, and rich porous structure. This review explores the use of SSBC for the adsorption of heavy metals, highlighting the impact of pyrolysis temperature on its surface properties, such as specific surface area and functional groups. Characterization techniques, including SEM, FTIR, XRD, XPS, AES, GC–MS, ICP, and ESR, are employed to analyze the chemical and structural properties of SSBC, providing insights into the changes that enhance its adsorption performance. Additionally, Artificial Neural Network (ANN) models are utilized to portend the adsorption efficiency of SSBC, offering a quantitative understanding of the relationship between heavy metal removal efficiency and biochar properties. This review emphasizes the importance of pyrolysis in optimizing SSBC for wastewater treatment and demonstrates how advanced characterization techniques and predictive models can guide the progress of more efficient biochar-based adsorbents for environmental remediation. The results highlight the promising role of SSBC in providing a sustainable remedy for heavy metal contamination in industrial wastewater.

Considering the escalating demand of lenses in various sectors, optical lens fabrication have got wide attention in present circumstances. Nevertheless, the structural complexity and precision were beyond the capabilities of conventional lens fabrication methodologies and hindered the time-efficient production. As a groundbreaking cutting-edge manufacturing technology, 3D printing has offered promising solutions for these difficulties and has showcased potential to produce multi-scale, multi-substrate and multi-functional lenses. Emerging printing techniques like FDM, SLA, DIW, Ink jetting and, TPP have demonstrated their potential in fabricating lenses using different materials and is found to be extensively used in eclectic range of applications. Synergizing post curing processes like meniscus equilibrium coating, rapid production of optical lenses with finer resolution and excellent surface smoothness is reported by advanced 3D printing techniques of Tomographic Volumetric Printing (TVP) and Micro Continuous liquid Interphase Printing (μCLIP) and a recent advancement in lens printing, zooming focused MIP-VPP technique, utilizing the frustum layer stacking can print complex lenses with reduced surface roughness and exceptional resolution without the requirement of post-curing. Elimination of staircase effect, printing characteristics and demonstration of commercial printing capability of the aforementioned techniques are discussed in this article. The review provides quantifiable data that illustrates the effectiveness of advanced 3D printing processes required for the production of optical lenses. For example, at 3.1 × 10⁴ mm³/h, Tomographic Volumetric Printing (TVP) obtained a surface roughness of 0.3340 nm, while Zooming-focused MIP-VPP yielded lenses with a roughness of 3.4 nm at 11.2 μm/s. Furthermore, the accuracy and effectiveness of these techniques were demonstrated by the fabrication of lenses using Micro-Continuous Liquid Interphase Printing (μCLIP) with an RMS roughness of 13.7 nm, a resolution of 1.32 μm, and a printing speed of 22.94 μm/s. By integrating features including high resolution, intricate geometry, and superior surface quality, these techniques help to enhance the advancements of complex optical devices, therefore making this discussion significant.

Origami-inspired fiber-reinforced composites exhibit inherent properties that showcase the extraordinary response of reinforcing fibers to stimuli-induced folding. This paper delves into origami-inspired fabrication techniques, meticulously integrating them into fiber-reinforced composites, with emphasis on kirigami and Miura-ori folding patterns, and other folding patterns like waterbomb, Yoshimura, and Kresling. The study highlights exemplary manufacturing methodologies, leveraging advanced techniques like electrospinning, 3D printing, and state-of-the-art 4D printing to create intricately engineered structures. Furthermore, the incorporation of shape memory polymers and hydrophilic polymers within the origami framework is thoroughly examined, revealing their transformative potential in imparting shape-shifting and hydrophilic properties to composites. Ultimately, this paper explores diverse applications of these meticulously engineered fiber-reinforced composites, unlocking their exceptional capabilities across multifaceted domains. This paper epitomizes the fusion of origami principles and material innovation, fostering a paradigm shift in composite materials. Incorporating various folding techniques enhances their potential to revolutionize structural design and enable novel applications in numerous industries.

Batteries play an integral role in our lives; their presence spans from cars to Mars rovers. Meeting the current demand for batteries involves extracting a significant number of ores. However, it's crucial to note that both the extraction and unsustainable recycling processes are considered high-carbon methods, resulting in the release of substantial CO2 emissions. This presents a significant concern contributing to global climate change. In alignment with this, India has pledged to achieve net-zero emissions by 2070. To address these environmental challenges, there is a growing need to adopt sustainable methods for battery recycling that effectively minimize the carbon footprint. This review delves into comprehensive discussions, encompassing both conventional and novel methods aimed at reducing the carbon footprint during the recycling of widely used secondary batteries. Additionally, the review explores the extraction of valuable materials such as lithium, nickel, lead, and cadmium from spent batteries. Concurrently, the review investigates the potential of artificial intelligence and machine learning, recognizing their substantial roles in precisely predicting battery life and advancing recycling processes. Through engagement with these multifaceted approaches, our aim is to mitigate the environmental impact of batteries while concurrently enhancing their efficiency and sustainability.

Natural fiber composites (NFCs) are increasingly recognized as sustainable and environmentally beneficial substitutes for traditional materials. The present study discusses chemical surface treatments that promote the adhesion of natural fibers and hydrophobic matrices, resulting in improved mechanical characteristics. The review aims to examine different chemical treatments, evaluate their influence on fiber qualities, and estimate the environmental consequences of NFCs using a life cycle assessment (LCA). It includes characteristics, advantages, and disadvantages of newly discovered fibers like acai, guaruman, and corn straw, and examines treatments like bromodecane, lime, and tannic acid, which improves adherence between fiber and matrices, providing better tensile, flexion, and impact intensity. Additionally, it examines the environmental benefits of NFCs, stressing their lower carbon footprint compared to synthetic composites. Critical data reveal that while chemical treatments considerably increase NFC performance, treatment choice must be adjusted to individual applications to combine mechanical qualities and environmental sustainability. This study broadens the knowledge of NFCs and provides routes for future research to build more efficient and eco-friendly composites with applications spanning the construction, automotive, and packaging sectors.

Hydroxyapatite (HA) finds widespread application in the realm of bone tissue engineering, owing to its renowned bioactivity and biocompatibility, alongside an expanding cohort of researchers who are actively investigating avenues for enhancing the physical attributes and biological functionalities inherent to hydroxyapatite. In recent years, the implementation of 3D printing based on extrusion technology has brought about a transformative change in the manufacturing of biomedical scaffolds. This review explores the significant parameters governing scaffold properties, including porosity, mechanical strength, and biocompatibility, with a particular emphasis on the scaffold's capacity to assist tissue regeneration, cell adhesion, and proliferation. The integration of rapid prototyping, a cutting-edge digital manufacturing technique, has facilitated the large-scale fabrication of intricate designs, exemplified by HA/PLA, HA/PCL, and HA-SA/PLA composites. These composites exhibit degradation rates reliant upon their physicochemical properties, heralding a new era in the fabrication of hard tissue structures and promising enhanced effectiveness in diverse medical applications. In addressing the limitations associated with metal implants, the review delves into the development and utilization of hydroxyapatite-metal matrix composites (MMC) like Mg-HA, Sr-HA, and Ti-HA in scaffold fabrication. The study also examines the implications of life cycle assessment (LCA) about the environmental impacts and human health considerations of these printed parts. By emphasizing the advancements in extrusion-based 3D printing, this review elucidates the transformative potential of this technology in the domain of biomedical engineering, particularly in the construction of hydroxyapatite scaffolds.

Dyes pose a significant environmental hazard due to their widespread use and tenacity in water bodies, resulting in adverse ecological and health effects. Many strategies have been investigated for the removal of dyes, and adsorption has emerged as a viable technique. Biochar-based adsorbents provide a sustainable alternative because of their high adsorption capacity, variable surface characteristics, and widespread availability. Biochar has improved adsorption properties similar to specific surface area, porosity, and total pore volume when mixed with metal nanoparticles due to synergistic interactions. It is crucial to comprehend the adsorption isotherm and kinetic models that control dye adsorption onto biochar because they provide insight into the mechanism and equilibrium behavior, respectively. The adsorption process's viability and energetics are further clarified by thermodynamic studies. Experiments and parameter optimization are guided by computational studies that use methods such as density functional theory (DFT) and response surface methodology (RSM) to optimize adsorption processes by giving insight into the system's relationship between multiple independent variables and multiple response variables and electron structure. This review also highlights the cost-effectiveness and sustainability of biochar/metal nanoparticle composites by discussing techniques for their regeneration and reuse and also explains the adsorption mechanism of dye by biochar/metal nanoparticle composites.

Direct ink writing (DIW) has emerged as an innovative and efficient method for gel synthesis, presenting numerous advantages over conventional techniques. Leveraging a diverse array of raw materials, DIW offers precise control over gel construction, facilitating the fabrication of materials with larger pore sizes. This capability contrasts with traditional methods like ionic gelation, which typically produce a maximum pore size of 130 μm. The increasing demand for materials with exceptional adsorption properties, especially for effluent treatment, has driven extensive research in this domain. While traditional gel preparation methods remain valuable, they exhibit inherent limitations. Thus, there is a pressing need for more efficient and scalable approaches to gel synthesis. DIW serves as a superior alternative, providing enhanced control over printing parameters and enabling the customization of materials to meet specific requirements. This paper not only addresses the limitations of traditional methods but also highlights the benefits of utilizing DIW for gel formulation. Additionally, it offers an overview of commonly employed adsorption isotherm and kinetic models and explores the applications of DIW-printed gels in effluent treatment. Given the expanding body of research in this area, this critical and comprehensive review underscores the potential of DIW in the adsorption of pollutants from wastewater.

The role of chitin has been focused in the domain of biochemistry, materials science, medicine, and environmental science due to its non-toxicity, biodegradability, thermostability, and biocompatibility. The projection period between 2023 and 2033 is predicted to have a significant Compounded Annual Growth Rate (CAGR) of 12.3 % in the worldwide chitin market and according to reports, the Young's modulus of chitin crystals is 150 GPa, which is comparable to cellulose crystals (134 GPa). In comparison to other chitin fabrication techniques like electrospinning and solvent casting, DIW method is more effective for producing complex 3D geometries. DIW is a flexible technique that covers a range of substances, such as natural polymers (carrageenan, cellulose, silk, chitin), synthetic polymers (polyurethane, polyvinylalcohol, acrylonitrile butadiene styrene), ceramics and composites in the form of ink. The present review provides an insight into the fabrication of chitin based products by DIW approach and introduces a key and essential acquaintance of chitin biopolymer-based ink creation in a variety of forms, including chitin nanofibers, and chitin whiskers, followed by the fabrication of polymer stripes patterned on chitin films with the ability to transform into intricate multidimensional architectures using the DIW process, and also highlighted the crucial and critical understanding of the utilization of chitin biopolymer-based materials in the engineering of bone tissue, shape-morphing film, and skin bearing architecture and their possible future in an abundance of industries.

Hydrogen is indeed an exceptional fuel due to its unique properties, including its large energy content by weight, clean burning, and high gross calorific value of 141.9 MJ/kg. It can reduce the serious problem of greenhouse gas exudations by substituting fossil fuels. Currently, there exist diverse methods for stockpiling hydrogen with their own merits and demerits. However, an effective approach is incessantly needed, and the wonder material borophene with extraordinary characteristics can provide it. This review informs the utilization of borophene in hydrogen storage through analysis of multiple computational studies on alkali or transition metal-decorated borophene employing density functional theory. It also encompasses the experimental synthesis of borophene and discusses US Department of Energy (DOE) standards and previously used adsorbent materials. Additionally, required improvements for effective hydrogen fuel-based transportation and safety precautions while stockpiling hydrogen are addressed.

Fiber-based thermoelectric generators are a versatile development in the field of power generation that has numerous applications in waste heat recovery and wearable technology. They differ from conventional thermoelectric generators, due to their flexible nature, which allows them to conform to the shapes of irregular surfaces and efficiently convert thermal energy to electrical energy, however, they retain the merits of reliability and longevity of their conventional counterparts. Their flexibility comes from the substrate onto which the thermoelectric materials are coated, several materials have been used as substrates, and of these materials, some have been more suitable for use than others. This review aims to assess the properties of some of these materials, their shapes, as well as material treatment methods that if implemented would enhance substrate surface properties by up to 139%, as well as changes to the shape and structure of fibers which would significantly enhance the thermoelectric performance and the longevity of fiber-based thermoelectric generators.

Owing to their wide range of applications, limited availability, and high cost, the removal and recovery of REE have become an essential and attractive process. Among the divergent conventional method employed for removing and recovering REE from wastewater streams, adsorption, ascribed to its feasibility, low energy consumption, economic adaptability, and low cost, have received persistent attention. Among different biopolymers, chitosan, the second most abundant, emerged as a preferential adsorbent owing to its characteristics which include non-toxicity, biodegradability, antimicrobial, and excellent physiochemical properties, which imparts high adsorption capacity (∼85–100%), selectivity, excellent surface area, porosity volume, high chelating power, and high hydrophilicity. This review provides a comprehensive overview of the most recent literature on the adsorption of rare earth elements (REE) by chitosan. The documented findings are elucidated with respect to (1) the toxic effects of different REE, (2) the efficacy of chitosan in the elimination and retrieval of diverse REE, (3) the utilization of functionalized chitosan in adsorption processes, and (4) the methods for regenerating, reusing, and scaling up chitosan adsorbents in industrial applications.

The scientific community has displayed an increasing interest in the materials and strategies for the development of origami structures capable of undergoing 2D to 3D transitions owing to their potential to create materials possessing fundamentally new functionalities and characteristics. Thin film residual stresses, mechanically active materials, or forces that arise from capillarity have been used as a mechanism to undergo folding deformations in engineered structures inspired by origami and have found potential in multiple arenas. The self-assembling, shape memory, and reversible properties of these smart materials have aided in maintaining the desired structure, and the ability of the material to withstand change after exposure and regain its original shape, which, encouraged this emerging innovative approach to meet current needs. In this article, a primary attempt has been carried out to consolidate the origami revolution over the last decade in various emerging fields, as well as its future applications and challenges. The emphasis has been provided on the designing of origami structures that permit the operationalization of advanced macro to nano-scale materials in 3D functional structures that have expanded their reach to multiple fields such as spacecraft, robotics, lithium-ion batteries, and biomedical applications.

Nickel ions play a crucial role as an essential micronutrient in both human beings and plants. However, the introduction and application of nickel ions augmented with industrialization, outpacing the expertise to access these materials beyond the planetary boundaries, causing nickel toxicity. Thus, the adsorptive removal of Ni2+ is earning ubiquitous significance attributed to the undesirable consequences on the ecosystem. The conceptualization of fabricating a sustainable material system, exterminating the prevailing challenges, thereby truncating the impact on the environment, and eradicating nickel ions from effluents was always a matter of substantial concern. Herein, we have fabricated PLA nano-microfibers via electrospinning technology with various Ti3C2 loading – 0.5, 1, and 3 wt%, introducing more porosity to the system to understand the applicability of these fibrous systems for Ni2+ removal. Incorporating Ti3C2Tx into the PLA matrix helps to fabricate a water-stable system further by increasing the adsorption capacity of PLA to 37.92 mg/g with 0.5 wt% Ti3C2Tx addition. The addition of Ti3C2Tx to the PLA matrix system and the surface morphology of the fabricated nanofiber composite were validated using FT-IR and SEM analysis, respectively. The biodegradable nature of the system was also explored under naturally mimicked conditions using cow dung slurry, where the 0.5 wt% loaded system demonstrated 12 % degradation within 30 days within the slurry. The induced biodegradability of the electrospun fibers, 3–17 % within 33 days, introduces an ideal and easily retrievable system for Ni2+ removal, eradicating potential hazardous effects on the ecosystem.

Concerns about climatic changes and global temperature enhancements have sparked efforts worldwide to curb the magnitude of atmospheric carbon dioxide. A key tactic for achieving carbon dioxide emission mitigation goals is Carbon dioxide capturing and sequestration, which is critical for the seamless changeover from the prevailing fossil-based power systems to more eco-friendly future energy systems. Among the carbon dioxide capturing techniques, post-combustion capture is the most practical method for retrofitting existing power plants although it result with 3–15 vol.% concentrated carbon dioxide gas stream. Chemical looping combustion capturing receives much attention receives much attention owing to its non-pollution nature and the yielding of highly concentrated carbon dioxide stream, up to 100%. This review also explores a variety of sequestration strategies, including geological carbon dioxide sequestration with multiple geological carbon dioxide storage sinks, mineral carbonation sequestration, as well as marine sequestration. The carbon dioxide transportation and the storage facilities comprising pressure vessels, pipelines, and cryogenic storage tanks are also discussed briefly. The Enhanced gas recovery, Enhanced water recovery, and Enhanced oil recovery, which rely on geologically stored carbon dioxide are also taken into account in this analysis as a part of the commercial-economic application of carbon dioxide capturing and sequestration. Along with the risk considerations related to the sequestration processes, the efficient exploitation of the sequestered carbon dioxide is delineated as a road map leading to future prospects. Concerns have been raised that the widespread adoption of carbon dioxide capturing and sequestration will likely be affected by the general public perceptions due to unawareness, along with potential leakage risks and the enormous capturing cost, which should be puzzled out for the effective uptake of carbon dioxide capturing and sequestration strategies.

In the present world, the depletion of the chief resources of energy, like fossil fuels, has prompted researchers all over the world to produce energy storage devices that dispense electronic properties superior to existing technology like rechargeable batteries. The morphology of electrodes of such devices has been a critical factor in establishing a ceiling on storage capacities, evoking within researchers a strong interest in nano materials for the reason that they possess remarkably high surface area, and ion and electron conduction properties. Carbon in this aspect is found to be a particular case, owing to its supreme conductivity values and excellent mechanical stability in various forms. In this review, an analysis of all modifications performed on carbon nanostructures to increase their storage capacity has been reported, with special emphasis on the gravimetric capacitance, cyclic stability, and densities (energy and power) of the subsequently formed supercapacitors (SCs). Towards the end, a discussion is initiated upon newer computational methods based on machine learning and artificial intelligence, for discovering novel 2D materials which could be potential candidates in compositing with carbon to reveal enhanced storage performance of SCs.

The removal of hazardous and life-threatening integrated effluents from contaminated water is a major trepidation, and the remediation process obtains reclaimed potable and sparkling water, where Geopolymer arose as the foremost effectual substance. Geopolymer-based materials are the representatives of a massive group of inorganic amorphous aluminosilicate materials with versatile industrial applications, and they have been recently developed as an ideal adsorbent owing to their chemical and physical stability as well as the skeletal network structure with the presence of terminally negative charged ions and porous nature along with the large surface area of ∼292.05m2g-1 with a removal efficiency of 98% for mesoporous geopolymer. Geopolymer, mainly derived from raw products like Metakaolin and Fly-ash, is frequently employed as adsorbents for removing toxic heavy metals, dyes, and radioactive nuclides. The current scientometric assessment aims to properly comprehend and evaluate the potential remediation of integrated effluents from wastewater thoroughly through various techniques such as adsorption, immobilization, and encapsulation using geopolymer-based materials. Advanced fabrication techniques like 3D Printing, spin-coating, and phase inversion, the detailed mechanism of adsorption, the introduction of various isotherms, and kinetic models, along with regeneration ability, have also been explained.

Anthropogenic CO2 emissions are indeed escalating as a consequence of the expanding global energy demand, emphasizing the significance of CO2 capture, where carbon capture and sequestration have been deemed to be the most efficacious approach for alleviating CO2 emissions. Multiple technologies have been devised to capture CO2, and current research is primarily aimed at improving CO2 adsorption on wood biochar, a carbonaceous substance derived from wood-based feedstock. Activation, metal doping, and surface group functionalization are some of the modification strategies being ultimately employed to enhance the adsorbent's effectiveness. The review also provides an insight into various Wood biochar production techniques moreover the adsorbent effectiveness assessment through a variety of isotherm and kinetic modeling techniques is also incorporated. This study summarizes different parameters like specific surface area (0.01- 1408.8 ​m2/g), pore volume (0.1-0.85 ​cm3/g), ash content (2.02-48.0%), and functional groups that stand as criteria for evaluating the adsorption ability of biochar. The CO2-adsorbed wood biochar employment as a sort of soil enhancer, feedstock material for biofuel, as well as the technique for warming up the building basement during frigid climates, is delineated as a roadmap leading to future aspects.

The Kaas lake is one of the unique sedimentary basins in the Northern region of the Western Ghats escarpment of India and preserves paleoclimate signals of the Holocene in its cover sequence over the lateritic basement. The signatures preserved in the lacustrine deposits, such as pollen, non-pollen palynomorphs, diatoms, and geochemistry of the sediments, were decoded and used to reconstruct the Holocene environmental changes of the Kaas Plateau in the Western Ghats. The main stages in the lake's evolution indicate the following: (1) low nutrient level and strongly changeable water levels in the early Holocene, (2) persistence of the oligotrophic state of the lake up to the last 2000 yr, and (3) strong cultural eutrophication of the lake in the recent period (c. 1000 years). The localized depression or a seasonal-lake favoured freshwater accumulation since 8.0 kyr BP and was probably dried sometimes after 2.0 kyr BP. A late Holocene peak of planktonic diatom and high organic recovery at the top level in the recent past (c. 1000 years) represents an event of eutrophication, possibly due to human impact. Being a seasonal lake, the plateau surface allowed clay accumulation with an extremely slow rate of 2.5 cm/10 kyr. Diatoms, pollen, and non-pollen palynomorphs together showed periodic fluctuations in lake hydrology, which was probably in response to climate-controlled vegetation on the Kaas Plateau. The diatom and sediment anomalies point to an ecological shift towards the mid–Holocene, supporting the hypothesis of increased Southwest Monsoons during the early Holocene around 8.0 kyr BP and the relative weakening of Northeast Monsoon after 2.5 kyr BP.

In the epoch of scarcity of environmentally friendly materials and global environmental change, sustainable materials stand out to meet the approach. Amongst abundant choices, Cellulose is found in enormous amounts in nature and is a green, inexhaustible asset. It is of expanding interest for a scope of utilizations pertinent to electronics devices because of its abundance in nature, high durability, structural strength, robustness, and flexibility. The initial component of biomass is cellulose and is highlighted in this review, following source of origins, including plants, bacteria, and algae. This review also emphasized various chemical, mechanical, and combined chemical and mechanical treatments to obtain various cellulose-based materials such as cellulosic nanofiber (CNF), nanofibril cellulose (NFC), and cellulosic nanocrystals (CNC), and regenerated cellulose film (RCF). Also, the areas of cellulose research such as green flexible electronics, wearable thermoelectric devices, electrode materials for flexible energy storage devices, high-performance bioelectronics devices, flexible electroluminescent devices, E-skin sensors, High performance green flexible electronics (Gallium arsenide-based HBTs, Silicon-based digital devices, submissive capacitor, and inductor) organic synaptic transistor, human motion sensors have been discussed at length.

As a substitute for conventional plastics in the market, bioplastics are winning their reputation. Pursuant to the researches carried out, in spite of being notably biodegradable in nature bioplastics have the similar qualities as conventional polymers. On the seeking for substitute for conventional plastics we found profusely existing, readily extractable algae as a superior source considering it does not rival with food roots for the bioplastic synthesis. This review covers the capacity of both microalgae and macroalgae in producing bioplastic considering polycarbohydrates present in the algae, such as cellulose, alginate, and carrageenan, have the ability to generate bioplastic. Consequently, the species employed as sources for bioplastic synthesis and various applications of algae-derived bioplastic were abbreviated.

Rechargeable energy storage devices (ESD) are becoming progressively momentous to our community, and conducting polymer (CPs) material is a core element of this device. With the rise in demand for high-powered, increased protection, economical, and environmental sustainability, substituting traditional redox-active material with conducting polymer is a favourable alternative for the rising generation of rechargeable ESD. This paper reviews polypyrrole and its modification as a bright cathode material for AZINs, SDIBs, LIBs, PIBs, and LISBs. Using the electrochemical polymerization, solvothermal technique, epitaxial polymerization, vapour polymerization, and oxidative polymerization, the Polypyrrole (PPy) composite can be fabricated to enhance its cyclability, current density, discharge capacity, low-temperature property and stop the loss of electrons in the electrolyte. The composite structure of PPy with a different class of material such as inorganic compound, metal sulfide, metal oxide, and alloys can be fabricated. Also, the other type of element is combined with PPy to improve their electrical and catalytic activity. This review highlights the PPy composite material in terms of cyclical performance, discharge capacity, and reversible capacity with different current densities. This review also highlights the forthcoming perspective of polypyrrole composite as up-and-coming cathode material for a higher-grade application.

The need of the hour is an economically viable energy storage system which proclaims the importance of MOF nanofibers. MOFs represents crystalline porous materials that are proficient in energy storage and conversion but on account of scarcity on interconnectivity between the porous structure and easy agglomeration, the electron transfer would be hampered so the electrospinning technique can be introduced. In electrospinning nanofibers are drawn at high voltage from viscoelastic fluid, which can be integrated with MOFs to resolve the incompatibility issues between them and to form MOF/polymer composite which have the peculiarities of both such as active sites, surface area, and flexibility that boost electrical conductivity. Nanofibers coordinated with MOFs for energy storage and conversion are not much reviewed, since it's a new insight. Convenient electrode material and electrocatalyst are requisite for energy storage and conversion which can be accomplished by electrospun MOF-based nanofibers. Firstly, we discuss the different methods to fabricate MOFs with electrospinning. Calcination of it can direct the generation of carbon-derived products, which improves the interconnectivity and electrical conductivity that enhances the electrode performance. In subsequent sections, the hydrothermal reaction which leads to the unification of metals or metal oxides with MOFs that stipulates more functionalities, and then-recent advancements in energy-storing devices like SCs, LIBs, SIBs, and fuel cells are also conversed. Lastly, some unfolded areas in this field are pointed out which could head the future research.

Foamed materials are honeycomb-shaped structures bearing porous networks which exhibit considerable compressive strengths, and excellent efficiency for oil-water separation. The presence of spilled oils and solvents in wastewater intensifies with accumulation over the time later creating toxicity to the environment. The ever growing industrial demands precede contamination of water sources which later make it difficult in its eradication. The scientific community has spearheaded the research towards materials exhibiting high oil/-solvent absorption capacity, compression strength, and recycling ability for the effective removal of accumulated spilt oils and solvents from wastewater. Recently, foamed materials have gained wide focus for oil/-solvent recovery due to high absorption capacity rendered by 3D porous structure present in the foams. Carbon-based lightweight (density = 0.2–0.8 g/cm3) foam exhibiting compressive strength of 20 MPa, porosity of 93%, and hydrophobicity (water contact angle = 149o), has been reported for oil-water separation application. In this sense, present review provides an in-depth study on various foams capable of removing the spilt oil/solvents from wastewater and their mechanism, toxic effects on the environment, and the factors affecting oil/solvent absorption performance of the foams, for the effective oil/solvent recovery.

Background: In a prior report, no patient with rodenticidal hepatotoxicity who met Kochi criteria (MELD score ≥36 or baseline INR ≥6 with hepatic encephalopathy) (PMID: 26310868) for urgent liver transplantation survived with medical management alone. Plasma exchange (PLEX) may improve survival in these patients., Objectives: We describe our experience with low-volume PLEX (PLEX-LV) in treating rodenticide ingestion induced hepatotoxicity in children., Methods: From prospectively collected database of rodenticidal hepatotoxicity patients managed as in-patient with department of Hepatology from December 2017 to August 2021, we retrospectively studied outcomes in children (≤18 years). Hepatotoxicity was categorized as acute liver injury (ALI, coagulopathy alone) or acute liver failure (ALF, coagulopathy and encephalopathy). Kochi criteria was used to assess need for urgent liver transplantation. The primary study outcome was one-month survival., Results: Of the 110 rodenticidal hepatotoxicity patients, 32 children (females: 56%; age: 16 [4.7-18] years; median, range) constituted the study patients. The study patients presented 4 (1-8) days after poison consumption (impulsive suicidal intent:31, accidental:1). Twenty children (62%) had ALI [MELD: 18 (8-36)] and 12 (38%) had ALF [MELD: 37 (24-45)].All children received standard medical care, including N-acetyl cysteine; ALF patients also received anti-cerebral edema measures. None of the patient families opted for liver transplantation. Seventeen children (ALI: 6, ALF: 11) were treated with PLEX-LV (3 [1-5] sessions, volume of plasma exchanged per session: 26 [13-38] ml/kg body weight) and peri-procedure low dose prednisolone.At 1 month, 28 of the 32 children (87.5%) were alive (4 ALF patients died). Of 10 children who met Kochi listing criteria for urgent liver transplantation, two children were ineligible for PLEX-LV (due to hemodynamic instability) and of the remaining 8 children treated by PLEX-LV, 6 (75%) survived., Conclusions: PLEX-LV shows promise as an effective non-liver transplant treatment in children with rodenticidal hepatotoxicity., (© 2022 Indian National Association for Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Background: Alcohol-related acute on chronic liver failure (A-ACLF) patients have high short-term mortality and are poor candidates for steroid therapy. Plasma exchange (PLEX) improves survival in ACLF patients. We analyzed our experience with low volume PLEX (50% of plasma volume exchanged per session) and low dose steroids to treat A-ACLF patients., Methods: We retrospectively compared the efficacy of low volume PLEX and low-dose steroids with standard medical treatment (SMT) in A-ACLF patients treated at our center between November 2017 to June 2019. The primary study outcome was one-year survival., Results: Twenty-one A-ACLF patients in PLEX group [age 40 (29-56) years, median (range); MELD score 31 (29-46)] and 29 A-ACLF patients in SMT group [age 41.5 (28-63) years, MELD score 37 (21-48)] were studied. All 50 study patients had severe alcoholic hepatitis [mDF 84.7 (50-389)]. PLEX group patients had 3 (1-7) PLEX sessions with 1.5 (1.4-1.6) liters of plasma exchanged per session and oral Prednisolone 20 mg daily, tapered over 1 month. Kaplan Meier analysis showed better survival over 1 year in the PLEX group compared to the SMT group ( P  = 0.03). There was renal dysfunction in 10 patients in the PLEX group, which normalized in six patients after PLEX., Conclusion: In this preliminary report, compared to SMT, low volume PLEX and low dose steroid improved survival over one year in A-ACLF patients with severe alcoholic hepatitis. In patients with renal dysfunction, 60% showed improvement in renal function with PLEX. Studies with a larger number of patients are needed to validate these results., (© 2021 Indian National Association for Study of the Liver. Published by Elsevier B.V. All rights reserved.)

Pregnancy-related liver disorders accounted for 8% of all maternal deaths at our center from 1999 to 2011. Of the three pregnancy-related liver disorders (acute fatty liver of pregnancy (AFLP), HELLP (Hemolysis, elevated liver enzymes, low platelets) syndrome and pre-eclamptic liver dysfunction, which can lead to adverse maternal and fetal outcome, AFLP is most typically under - diagnosed. Risk of maternal death can be minimised by timely recognition and early/aggressive multi-specialty management of these conditions. Urgent termination of pregnancy remains the cornerstone of therapy for some of these life threatening disorders, but recent advancements in our understanding help us in better overall management of these patients. This review focuses on various aspects of pregnancy-related liver disorders.

The changes in retinoid metabolism have been documented in liver cirrhosis. However, the dynamic alterations in levels of this vitamin between circulation and liver during development of the liver cirrhosis are not well understood. The aim of this study was to measure retinoids in the liver and circulation in parallel, during and after development of cirrhosis induced by carbon tetrachloride and thioacetamide. Retinoid levels were measured by HPLC. A decrease in retinaldehyde and total retinol, together with an increase in retinoic acid was evident in liver from both carbon tetrachloride or thioacetamide treated rats within a month after initiation of treatment. Activity of enzymes involved in retinoid metabolism such as retinaldehyde oxidase, retinaldehyde dehydrogenase, and retinaldehyde reductase were decreased in the liver. In parallel, levels of retinol and retinaldehyde in the serum were increased while retinoic acid was decreased. This study indicates that during development of cirrhosis, there is reciprocal transfer of retinoid metabolites between the circulation and the liver.

Nonsteroidal anti-inflammatory drugs (NSAIDs), used extensively in clinical medicine, tend to cause adverse effects in the gastrointestinal tract. Earlier work has shown that oral administration of indomethacin produced oxidative damage in the small intestine and attenuation of the glycocalyx layer of the mucosa. The present study assessed, in greater detail, the alterations produced in the glycocalyx of rat small intestinal mucosa in response to indomethacin, with specific reference to surfactant-like particles (SLP) and brush border membranes (BBM). Changes in gut flora in response to the drug were also studied, as it has been shown that luminal bacteria play a role in the pathogenesis of NSAID-induced intestinal damage. The levels of sugars such as sialic acid, fucose, hexose and hexosamine were increased in SLP and decreased in the BBM following indomethacin treatment, with the effects being maximal 24h after the administration of the drug. The composition of lipids in the SLP was also found to be altered. There was a significant increase in the number of bacteria in the luminal contents of the small intestine and caecum in these animals, as compared with controls. The number of bacteria adherent to the intestinal mucosa was also significantly higher in the drug-treated group. In vitro studies revealed that there was an increased tendency for bacteria to adhere to SLP isolated from indomethacin-treated rats. These results suggest that alterations in glycosylation of SLP and BBM in response to indomethacin, along with qualitative and quantitative changes in the luminal bacterial flora, may facilitate translocation of bacteria into the mucosa. These changes may contribute to the enteropathy observed as a result of NSAID treatment.

Oxidative stress in the small intestine can result in altered cell proliferation, migration, and differentiation of villus-crypt cells. Retinoid metabolism is recognized as an important mediator of cellular differentiation in the intestine. This study examined the effect of oxidative stress in retinoid metabolism in a surgical stress model. Surgical stress was performed by handling the intestine as done during laparotomy. Villus-crypt cells were isolated at different time periods and various retinoid concentrations in the cell homogenate and the retinoic acid forming enzymes were quantitated using HPLC. Surgical stress resulted in altered retinoid levels in various cell populations in the small intestine at 1 and 12h. The activity of alkaline phosphatase and retinal oxidase was also altered at these time points and all these changes were prevented by inhibiting superoxide generation using xanthine oxidase inhibitor, allopurinol. These studies suggest that alterations seen in enterocytes during surgical stress may be mediated by changes in retinoid metabolism.

A simple method for preparation of brush border membranes (BBM) from rat kidney using polyethylene glycol (PEG) precipitation has been described. This method avoids the use of cations for the preparation, which might alter membrane lipid composition. These preparations were assessed for enrichment of marker enzymes, contamination by subcellular structures, lipid composition and transport function. An enrichment of 11.8910-fold of alkaline phosphatase, 13.9500-fold of amino peptidase and 13.6500-fold of gamma-glutamyl transpeptidase and an approximate yield of 60% were seen in the final membrane preparation as compared to the homogenate. There was very little contamination of basolateral membranes, peroxisomes, microsomes or lysosomes in the final membrane preparation. Analysis of sugars indicated high content of fucose and sailic acid as compared to hexoses. Isolated membranes appeared as vesicles as seen by electron microscopy. Lipid analysis indicated the presence of various neutral and phospholipids with a high content of sphingomyelin along with a cholesterol/phospholipid ratio of 0.4850. The isolated membrane vesicles were able to transport glucose. This study has shown a simple method of renal brush border membrane preparation, which is comparatively pure and functionally active.

A novel method of brush border membrane vesicle (BBMV) preparation from the small intestinal mucosa using polyethylene glycol (PEG) precipitation has been presented. This preparation is compared with calcium-precipitated BBMVs in marker enzyme enrichment, contamination by other subcellular membranes, transport of glucose, and lipid composition. PEG-precipitated BBMVs are comparable with calcium-precipitated membranes in all parameters except lipid composition and thiol content. PEG-precipitated membranes have more phosphatidylcholine and phosphatidylethanolamine and less lysophosphatidylcholine and lysophosphatidylethanolamine as compared to calcium-precipitated membranes. Diacylglycerol and triacylglycerol content are also high in PEG-precipitated membranes. Alteration in lipid composition indicate the possible activation of lipase and phospholipase by calcium during BBMV preparation, which is not seen in PEG precipitation. Thiol content is almost double in PEG-precipitated membranes as compared to calcium-precipitated membranes. These results indicate that PEG can be used for the preparation of BBMVs in native form from the intestine without any alteration in their structural components, and these membranes show comparable transport activity., (Copyright 2001 Academic Press.)

Apoptosis is a critical determinant of tissue mass homeostasis and may play a role in carcinogenesis. The aim of the present study was to investigate anoxia-induced cell death in colon-derived HT29 cells and the effect of nitric oxide on this phenomenon. It was found that HT29 cells subjected to anoxia undergo apoptosis in a time dependent manner, as determined by DNA fragmentation and Hoechst-33258 dye staining. Cytochrome c release from mitochondria to cytosol is a key step in this process and this release precedes DNA fragmentation. NO inhibits anoxia induced apoptosis in these cells by inhibiting the release of cytochrome c and thus may play a role in modulating the apoptotic cell death of colon-derived epithelial cells., (Copyright 1999 Academic Press.)

Glutathione (GSH) is important in maintaining intracellular thiol status. The present study looked at the effect of GSH depletion on lipid composition of colon-derived HT-29 cells. GSH was depleted in HT-29 cells by incubation either with buthionine-S, R-sulfoximine (BSO) or diethylmaleate (DEM). GSH was restored during early periods of cells growth by supplementation of growth medium with either GSH ester or N-acetyl cysteine (NAC). Lipids were analysed following GSH depletion and supplementation. Among the neutral lipids, an increase in free cholesterol and diacylglycerol and decrease in cholesteryl ester and triacylglycerol were seen in GSH-depleted cells as compared to control cells. There were no detectable free fatty acids either in control or GSH-depleted cells. Among the phospholipids, a decrease in phosphatidylcholine and phosphatidylinositol and an increase in phosphatidylethanolamine were observed. These changes were a completely reversed by supplementation of BSO-treated cells with GSH ester and partially reversed by N-acetyl cysteine. These results suggest that the GSH status of the cell plays an important role in the lipid composition of the cells.

We have earlier shown that enterocyte mitochondria contain a phospholipase D (PLD) activity which can be stimulated by oxygen free radicals, divalent cations and polyamines. The functional significance of this enzyme in mitochondria is not known but it can be investigated using selective inhibitors. In the present study, mitochondrial PLD was activated by exposure to oxidants (X+XO or menadione), calcium or polyamines and the effect of antimalarial drugs, chloroquine, amodiaquin and primaquine on PLD activity was studied. Chloroquine and amodiaquine inhibited Ca2+ stimulated PLD activity in dose dependent manner whereas these drugs had no significant effect on PLD activated by oxidants or polyamines. Increasing the calcium concentration relieved the PLD inhibition by these drugs. Primaquine did not have any effect on calcium stimulated PLD activity whereas it slightly activated the enzyme. These results indicate that chloroquine and amodiaquine may bind with calcium making it unavailable for PLD activation.

Mitochondrial damage is one of the prominent features of cell injury during oxidative stress and altered mitochondrial lipids may contribute to this damage. Lipid changes were observed when liver mitochondria were exposed to superoxide generating systems. Phosphatidylcholine and phosphatidylethanolamine contents were decreased with simultaneous formation of lysophospholipids when exposed to superoxide. Among the neutral lipids there was an increase in the level of free fatty acids. This alteration in lipid composition could be prevented by the simultaneous presence of superoxide dismutase or phospholipase A2 (PLA2) inhibitors. H2O2 did not have any effect on liver mitochondrial PLA2. This suggests that superoxide anion stimulates phospholipase A2 which is prevented by superoxide scavenging agents and PLA2 inhibitors. The products of phospholipase A2 are membrane-damaging agents which may be responsible for mitochondrial damage seen during oxidative stress.

Modification of protein thiol by mixed disulfide formation with low molecular weight cellular thiols has been proposed as one of the post-translational modifications of amino acid side chains and is known to be catalyzed by thioltransferase. Intestinal mucosa is susceptible to oxidative injury and is likely to form protein mixed disulfide during oxidative stress. In the present study thioltransferase was purified from monkey small intestinal mucosa and its role in protein-s-thiolation was investigated. The purified enzyme was homogeneous, as judged by polyacrylamide gel electrophoresis under reducing conditions. The enzyme, with a molecular weight of 52 kDa, was a monomeric protein, which showed optimum activity at pH 8.0 with hydroxyethyl disulfide as substrate. The enzyme specifically cleaved the disulfide bond of the synthetic substrate, hydroxyethyl disulfide, in the presence of reduced glutathione (GSH) with the formation of oxidized glutathione (GSSG) as shown by high performance liquid chromatography. The enzyme also catalyzed protein thiolation of monkey intestinal mitochondria when incubated with glutathione disulfide. These studies have shown that thioltransferase purified from intestinal mucosa could catalyze dethiolation and thiolation.

The colonic lumen is likely to contain oxidants derived from unabsorbed dietary materials including transition metals, rancid fat, drugs and bacterial metabolites. The present study looks at the effect of luminal exposure of different oxidants on colonic mucosal lipid peroxidation and absorptive function. All the oxidants tested induced fluid and electrolyte secretion and indomethacin, a prostaglandin synthesis inhibitor reversed this effect. Oxidants did not induce mucosal lipid peroxidation. This study suggests that oxidants induce functional alterations in colon possibly through stimulation of prostaglandin generation without influencing mucosal lipid peroxidation.

Oxidative stress is associated with the formation of oxidized glutathione (GSSG) in the cells, which can form mixed disulfide with proteins leading to alteration of their function. The present study looks at the effect of in vitro exposure of GSSG on intestinal mitochondria and brush border membrane (BBM). Incubation with 1 mM GSSG increased the protein bound GSH in mitochondria by 15-fold. This was associated with loss of activity of certain mitochondrial enzymes such as succinic dehydrogenase, isocitrate dehydrogenase, total ATPase and NADH dehydrogenase whereas NADH oxidase was not affected. A similar treatment of BBMV with GSSG increased the protein bound GSH by 4.7-fold without altering its enzyme activity. Exposure to GSSG had no effect on the Na(+)-dependent glucose transport by BBMV. These studies suggest that GSSG formed during oxidative stress may modify thiol groups in proteins by forming mixed disulfides leading to functional alteration of certain cellular proteins.

Rat liver and intestinal microsomes were exposed to various free radical generating systems and their effect were assessed by studying different parameters such as formation of malonaldehyde (MDA) and conjugated diene, arachidonic acid depletion and alteration in protein thiol groups and tocopherol levels. These studies revealed that liver being highly vulnerable tissue showed all the effects of free radical attack whereas intestinal microsomes were resistant to most oxidants except iron independent generation of free radicals using 2-2'-azobis (2-amidinopropane) dihydrochloride (ABAP). Intestinal microsomes were found to contain considerable amount of non-esterified fatty acids in total lipid fraction as compared to liver microsomes and iron-fatty acid complex may be incapable of participating in peroxidation. In vitro measurement of hydroxyl radical generation showed that intestinal microsomes were incapable of generating these active species. These results suggest that iron dependent free radical mediated lipid peroxidation might not occur in intestinal epithelial cells.

The gamma-glutamyltransferase activity of erythrocytes was estimated in healthy adults and in patients with hepatobiliary disease. Control activity was 1.97 +/- 0.70 X 10(-4) U/mg ghost protein. Activity was elevated to 8.54 +/- 7.81 X 10(-4) U/mg in patients with hepatobiliary disease. Very high values, above 15 X 10(-4) U/mg were seen in patients with primary and secondary liver carcinoma, and also in some patients with obstructive jaundice. The erythrocyte enzyme had the same kinetic properties as serum and liver enzymes and was inhibited by serine-borate mixture, a specific inhibitor of the enzyme. There was no correlation between the erythrocyte enzyme level and either plasma hydrophobic enzyme level or erythrocyte glutathione content.

A method has been developed for the localization of gamma-glutamyltransferase (gamma-GT) on polyacrylamide gels using L-gamma-glutamyl-p-nitroanilide as substrate. The optimum conditions for staining on polyacrylamide gels with this substrate were evaluated and compared with the staining method using N-gamma-L-glutamyl-alpha-naphthylamide as substrate. Using papain digested, purified gamma-GT from human fetal liver it was shown that the method could be used for quantitation of the enzyme on polyacrylamide gels. It was also shown that identical patterns of staining for serum gamma-GT could be obtained with L-gamma-glutamyl-p-nitroanilide and N-gamma-L-glutamyl-alpha-naphthylamide as substrate.

A new method is described for the separation of hydrophobic and hydrophilic forms of gamma-glutamyltransferase (GGT) present in human serum using hydrophobic chromatography on phenyl-Sepharose CL-4B columns. The analysis of sera of 30 normal healthy people showed that 71.49 +/- 8.73% (mean +/- SD) of the GGT was in the hydrophilic form. In sera from 52 patients with various liver diseases the major part of the total enzyme was hydrophobic GGT, contributing 67.38 +/- 13.8% of the total GGT activity. Elevated total serum GGT and a hydrophobic to hydrophilic ratio of more than one helped in diagnosing hepatobiliary disease in 51 of 52 patients. Papain digestion of serum converted hydrophobic to hydrophilic GGT, which was similar to soluble form of liver GGT. The results are discussed in relation to the proposed mechanisms of release of GGT from the liver to the circulation.