Search

This study is being carried out to evaluate and compare the stress along the root surfaces of anterior maxillary dentition during retraction in labial and lingual mechanics with varying level of bone support. Eight three-dimensional finite element models (FEM) were created with normal periodontium and different levels of alveolar bone loss; four with labial brackets and four with lingual brackets. Sliding mechanics were simulated as en-masse retraction of the anterior dentition. The equivalent stresses along the roots of six anterior maxillary teeth were measured in all the models. Equivalent stresses generated at the root surfaces of central incisors are always higher in labial technique and of canines are always higher in lingual technique, suggesting the increased vulnerability toward root resorption in both cases. Stresses at the root apices of all the teeth are increasing progressively when the bone loss is progressively more than 2 mm in labial technique. In labial technique, the stresses at the root apices of all the teeth are increasing progressively when the bone loss is progressively more than 2 mm. In Lingual technique, equivalent stresses generated at the root surfaces of canines are more than central and lateral incisors irrespective of the alveolar bone loss, suggesting increased susceptibility to root resorption.

The aim of this is to evaluate the biomechanical performance of double-level semirigid pedicle screw fixation and artificial intervertebral disc replacement in lumbar spine. Ti6Al4V and CFR-PEEK material are used for pedicle screw fixation and artificial disc replacement. In the present study, pedicle screw fixation and artificial intervertebral disc replacement are carried out between L3-L4-L5 regions under the application of moment 6,8,10 Nm and range of motion is compared during flexion, extension, and right-left lateral bending. Two-level pedicle screw fusion and total disc replacement are developed in the L3-L4-L5 of the lumber spine vertebrae. Carbon fiber reinforced (CFR-PEEK) and ultra-high molecular weight polyethylene (UHMWPE) are considered for the spinal fusion and the core part of the artificial disc respectively. Afterwards, applying the finite element analysis, it is detected that CFR-PEEK rod is able to increase range of motion at the implanted level in comparison to Ti6Al4V rod for both flexion–extension and lateral bending. In case of artificial intervertebral disc replacement hypermobility was observed. Hence, it is significant that rod material with CFR-PEEK is a better alternative for the treatment of degenerative diseases.

Water quality assessment is key to the conservation and management of rivers. River Saraswati, a distributary of the river Ganga, serves as a lifeline to many villages in the district Hooghly in West Bengal, India. As the river is gradually dying due to diverse man-made pollution, ten water quality parameters in two sampling spots (PR-1 and PR-2) in the river are monitored month-wise from March 2017 to February 2020, and these are compared with those from a reference pond. The water quality index (WQI) is determined for the two riverine spots and the reference pond based on the Canadian Council of Ministers of Environment WQI (CCMEWQI) and weighted arithmetic WQI, respectively. In addition to actual observations, three different forecasting methods, exponential smoothing, autoregressive integrated moving average, and artificial neural network, are used to predict WQI for the next two years. This study indicates that free CO2, dissolved oxygen, and turbidity are the key parameters to evaluate this river's anthropogenic stress and health. The actual and forecasted results reflect the precipitous degradation of CCMEWQI in PR-2. Therefore, the immediate intervention of all stakeholders is required to adopt an integrated and comprehensive river management plan to save the river from utter obliteration.

Anthropogenic activities targeting economic progress have triggered changes in the Earth system processes causing depletion of resources and degradation of ecosystems. Water is a critical natural resource which has been severely impacted through groundwater depletion, surface water contamination and ocean acidification resulting in repercussions on human health and biodiversity losses. Likewise, India, a mega biodiversity nation has been critically affected by degradation and drawdown of water resources with far-reaching consequences on environmental vitality and socio-economic development. In order to prevent extreme water scarcity in the near future, the country needs to promote sustainable utilisation of water resources by adhering to the targets of Goal 6 of the United Nations Sustainable Development Goals (UN-SDGs). The present work, therefore, has focussed on the development of a Water Sustainability Index (WSI) for India that would help attaining the targets of SDG 6. A total of 12 indicators categorized under biophysical and social development dimensions and synonymous with the targets of SDG 6 have been used for the formulation of WSI and thereby understanding how much water resources are used annually in a sustainable manner. The study also highlights the interrelationship between the diverse social development and health indicators (SDG 3) of Indian community. The research has the potential to provide guidance for efficient use of water resources in India. Acting as a yardstick and guiding star, the sustainability metric will help the nation to monitor whether it is on the right track and navigate its journey towards achieving water sustainability. It also calls for cautious course correction and restructuring of current Indian policy and operational instruments for effective green governance and sustainable water management.

For the treatment of degenerative disc disease (DDD) and associated back pain and instability in the spinal segments, the success of pedicle screw-based spinal implant system has been found in the literature. Over the last couple of years, various nonfusion implants are made for the treatment of minor DDD. In this study, the biomechanical response of pedicle screw-based implant with semi-rigid rod material on the lumbar spine is evaluated. Computed tomography (CT) scan-based finite element (FE) model is used to evaluate the performance of pedicle screw fixation with flexible rods made of carbon fiber-reinforced polyetheretherketone (CFR PEEK). Typical physiological loadings are applied to the intact and implanted lumbar spine model. It is observed that the pediclescrew with the CFR-PEEK rod can restore the range of motion (ROM) on the surgical segment. The CFR-PEEK RODs carried out more loads and reduced the stress on the vertebral body. Using traditional rigid rods, ROM is generally almost restricted on the fusion zone, which can be improved by CFR-PEEK rod system to a certain degree. After successful experimental validation and clinical trial, the CFR-PEEK rod may be recommended for improved clinical outcomes.

Plants require zinc (Zn) as an essential micronutrient since Zn plays important roles in metabolism. Arsenic (As) is a toxic metalloid whose accumulation in plants hampers growth of plants. Rice crops are grown under flooded conditions that make them vulnerable to double jeopardy of Zn deficiency andAs stress. The goal of this study was to observe the effect of ZnO nanoparticle (NPs) and ZnO-NPs + biochar on As and Zn accumulation in and growth of rice plants grown under flooded conditions. The study area was Chausa block in Buxar district, Bihar, India. Rice crops were treated with 80 mg L-1 of ZnO-NPs and biochar was added to soil at rate of 10 t ha-1. ZnO-NPs were sprayed at heading and jointing stage of crop development. The results showed a significant increase in plant biomass and total chlorophyll content in ZnO-NPs and ZnO-NPs + biochar with respect to control. The decline in electrolytic leakage and malondialdihyde (MDA) content was observed to be 48-62% and 14-55%, respectively in treated plants as compared to control. Further, As accumulation was reduced in rice tissues and grains while Zn accumulation was increased. The enzymes superoxide dismutase (SOD), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), and catalase (CAT) showed higher activity in treated crop plants than in control plants. The findings confirm that ZnO-NPs and their combined use with biochar in flooded regions can help to improve growth, yield and reduced As accumulation in rice plant.

Lumbar pedicle screw is one of the most common and important elements in the field of lumbar surgery. It plays a great role in rectifying the spinal alignment and stabilization providing strength and stability to the affected area of spine. In spinal surgery, minimally invasive techniques and minor incisions are made which makes it less painful for the patients than the traditional methods. Moreover, the screws are not needed to be removed after the surgery which is yet another great advantage of the pedicle screw.In this study, 3D Finite Element (FE) model of human L4 vertebrae is taken for analysis using image processing tool. Pedicle screw design with varying mechanical and geometrical properties has been carried out at different applied loads on it along with considering the effect of frictional forces between all contact surfaces.Mathematical relationship among stress, strain, pitch of the screw and diameter have been developed for different thread profiles which will be beneficial for researchers for further development of pedicle screw implants.Results from the different analysis shows that bending stress on the screw for different loads at triangular pitch is higher than the trapezoidal. Hence, trapezoidal thread is efficacious than triangular thread. In case of vertebral bone, the magnitude of stress is less for trapezoidal screw than triangular and stress has a linear relationship with pitch length. In term of strain, triangular thread develops more strain than trapezoidal thread. A set of mathematical relation has been developed for different thread profile based on pitch length, stress and strain which gives the idea about von Mises stress and strain.

Rising global temperature, pollution load, and energy crises are serious problems, recently facing the world. Scientists around the world are ambitious to find eco-friendly and cost-effective routes for resolving these problems. Biochar has emerged as an agent for environmental remediation and has proven to be the effective sorbent to inorganic and organic pollutants in water and soil. Endowed with unique attributes such as porous structure, larger specific surface area (SSA), abundant surface functional groups, better cation exchange capacity (CEC), strong adsorption capacity, high environmental stability, embedded minerals, and micronutrients, biochar is presented as a promising material for environmental management, reduction in greenhouse gases (GHGs) emissions, soil management, and soil fertility enhancement. Therefore, the current review covers the influence of key factors (pyrolysis temperature, retention time, gas flow rate, and reactor design) on the production yield and property of biochar. Furthermore, this review emphasizes the diverse application of biochar such as waste management, construction material, adsorptive removal of petroleum and oil from aqueous media, immobilization of contaminants, carbon sequestration, and their role in climate change mitigation, soil conditioner, along with opportunities and challenges. Finally, this review discusses the evaluation of biochar standardization by different international agencies and their economic perspective.

Instability in the spinal section along with the cases of degeneration is commonly cured by the pedicle screw fixation system. The present work aims at the identification of suitable instrumentation at the spinal segment L4-L5 through finite element method and compared with an intact spine. Vertebral section (L3- Coccyx) upper surface L3 were subjected to various axial compressive forces for the body weights of 17, 67, 100 and 167 kg under the different physiological motion conditions such as rotation, flexion, extension and bending. Considering Intact as 100% the calculated results of equivalent stress on IVD-L34, L45 and L5S are as 90%, 43% and 76% during flexion, for extension 118%, 26% and 108%, during bending 58%, 58% and 80% and during rotation 57%, 46%, 74% respectively are the lowest for 6 mm instrumentation as compared to other instrumentation model. It was also observed that the load on the cortical and annulus region were highest as compared to the cancellous and nucleus region. The results of the present study can contribute to explaining fracture and intervertebral disc replacement cases subjected to pedicle screw implantation.

Cadmium (Cd), a major contaminant of concern, has been extensively reviewed and debated for its anthropo-genic global shifts. Cadmium levels in rice grains raise wide food safety concerns. The aim of this review is therefore to capture the dynamics of Cd in paddy soil, translocation pathways of Cd from soil to consumption rice, and assess its bio-accessibility in human consumption. In crop plants, Cd reduces absorption of nutrients and water, triggers oxidative stress, and inhibits plant metabolism. Understanding the mechanisms and behaviour of Cd in paddy soil and rice allows to explain, predict and intervene in Cd transferability from soil to grains and human exposure. Factors affecting Cd movement in soil, and further to rice grain, are elucidated. Recently, physiological and molecular understanding of Cd transport in rice plants have been advanced. Morphological -biochemical characteristics and Cd transporters of plants in such a movement were also highlighted. Ecologi-cally viable remediation approaches, including low input cost agronomic methods, phytoremediation and mi-crobial bioremediation methods, are emerging.

Soil organic carbon (SOC) is a key soil quality indicator, as it is a source and storage of plant nutrients and plays a vital role in soil fertility and productivity maintenance. Intensification of agriculture is known to cause SOC decline; however, much of the evidence stems from field-scale experimental trials. The primary aim of this study is to investigate how more than 20 years of agricultural land use intensification in Bangladesh has influenced SOC levels at landscape levels. This was achieved by revisiting in 2012 four sub-sites from the Brahmaputra and Ganges alluviums which were previously sampled (1989–92) by the Soil Resource Development Institute and collecting 190 new samples. These were located at different elevations and subjected to differing amounts of inundation. The SOC was determined using the same method, potassium dichromate wet oxidation, used in the 1989-92 campaign. A comparison of the SOC in the 2012 samples with their historic levels (1989–92) revealed that overall SOC declined significantly across both alluviums as well at their four sub-sites. Further analysis, however, showed that SOC has declined more at higher sites. The higher sites are inundated to a limited level, which makes them suitable for growing multiple crops. Among the land types considered here, the low land sites (because of their topographical position) remain inundated for a greater part of the year, allowing a maximum of only one crop of submerged rice. As a result of reduced biomass decomposition due to anaerobic conditions when inundated, and lower land use/cropping intensity, SOC accretion has occurred in the lower land sites.\ud The SOC levels in South Asian countries are inherently low and agricultural land use intensification fuelled by growing food production demand is causing further SOC loss, which has the potential to jeopardise food security and increase the environmental impact of agriculture.

Titanium alloy-based Pedicle screw-rod fusion is a very common technique to provide higher fusion regularity than other methods. In recent times, Carbon-fibre-reinforced (CFR)-PEEK rod is used to better reduce the fusion rate. Alternatively, total disc replacement (TDR) is also very common for the non-fusion treatment method for degenerative disc disease (DDD). This study aims to investigate flexibility (ROM), stability, stress condition in implant, implant adjacent bone of the implanted lumbar spine during different physiological movements and loading environments. The finite element (FE) intact model of the lumbar spine (L2-L5) with two-level pedicle screw-rod fusion at L3-L4-L5 and two-level artificial disc replacement was developed. CFR-PEEK was taken for rod for semi-rigid fusion. UHMWPE was taken as core part of the artificial disc. The FE models were simulated under 6, 8 and 10 Nm moments in left right lateral bending, flexion and extension movements. The total ROM was reduced for two-level pedicle screw fixation and increased for the artificial disc replacement model during flexion extension compared to the intact spine. The total ROM was reduced by around 54% and 25% for two-level fixation and increased by 30% and 19.5% for artificial disc replacement spine, under flexion-extension and left-right lateral bending respectively. For screw fixation, the ROM increased by 15% and 18% reduced by 4.5% and 14% for disc replacement at the adjacent segments for flexion-extension and left-right lateral bending.

usc The accumulation of microplastics (MPs) and nanoplastics (NPs) in terrestrial and aquatic ecosystems has raised concerns because of their adverse effects on ecosystem functions and human health. Plastic waste management has become a universal problem in recent years. Hence, sustainable plastic waste management techniques are vital for achieving the United Nations Sustainable Development Goals. Although many reviews have focused on the occurrence and impact of micro- and nanoplastics (MNPs), there has been limited focus on the management of MNPs. This review first summarizes the ecotoxicological impacts of plastic waste sources and issues related to the sustainable management of MNPs in the environment. This paper then critically evaluates possible approaches for incorporating plastics into the circular economy in order to cope with the problem of plastics. Pollution associated with MNPs can be tackled through source reduction, incorporation of plastics into the circular economy, and suitable waste management. Appropriate infrastructure development, waste valorization, and economically sound plastic waste management techniques and viable alternatives are essential for reducing MNPs in the environment. Policymakers must pay more attention to this critical issue and implement appropriate environmental regulations to achieve environmental sustainability. Refereed/Peer-reviewed

Emerging contaminants (ECs) or contaminants of emerging concern (CEC) are environmental contaminants of human and/or ecological health concerns, which are not currently controlled or have been only recently regulated. Last few decades have witnessed discharge of increasing concentration of diverse ECs classified as pharmaceutical and personal care products (PPCPs) and endocrine disrupting compounds (EDCs) into the environment down the drains at an unprecedented rate and scale due to intense human consumerism, urbanization, and industrialization activities. For treatment of wastewater contaminated with ECs both conventional treatment methods like activated sludge process and several emerging methods of treatments including biological treatment process and advanced oxidation process show several limitations and constraints used. Recently, nanomaterials have drawn increasing attention of scientists and engineers due to their unique properties and functional features, for example the adsorption capacity of various metal ions onto their surface. The nanomaterials are divided into four main groups based on their role in adsorption namely metallic nanoparticles (e.g., gold nanoparticles), metallic oxide nanoparticles (aluminum trioxide or titanium dioxide), nanostructured mixed oxides (nanostructured binary iron-titanium mixed oxide particles) and magnetic nanoparticles (iron oxide NPs). Carbonaceous nanomaterials (CNMs) are all together a different group of nanoparticles among which important as adsorbents are carbon nanotubes (CNTs), carbon nanoparticles (CNPs), and carbon nanosheets (CNSs). Nanoadsorbents can be synthesized by physical, biological, and chemical methods. The efficacy of nanoadsorbents depends on their innate surface properties, intrinsic composition, apparent size, and external functionalization of nanosorbent materials. There are a number of factors that affect the adsorption process like, pH, ionic strength, dissolved organic matter, etc. The present book chapter presents how nanoadsorbents endowed with a suite of unique properties can open windows of opportunities as more effective next generation tools for adsorption than conventional adsorbents. Future novel studies can focus on the improvement of nanoadsorbent properties like chemical stabilization and improve surface adaptations as to improve its efficacy in wastewater treatment and to find out the disadvantages of nanoadsorbents to further overcome their shortcomings in near future.

Fast weathering of parent materials and rapid mineralization of organic matter because of prevalent climatic conditions, and subsequent development of acidity and loss/exhaustion of nutrient elements due to intensive agricultural practices have resulted in the degradation of soil fertility and productivity in the vast tropical areas of the world. There is an urgent need for rejuvenation of weathered tropical soils to improve crop productivity and sustainability. For this purpose, biochar has been found to be more effective than other organic soil amendments due to biochar's stability in soil, and thus can extend the benefits over long duration. This review synthesizes information concerning the present status of biochar application in highly weathered tropical soils highlighting promising application strategies for improving resource use efficiency in terms of economic feasibility. In this respect, biochar has been found to improve crop productivity and soil quality consistently through liming and fertilization effects in low pH and infertile soils under low-input conditions typical of weathered tropical soils. This paper identifies several advance strategies that can maximize the effectiveness of biochar application in weathered tropical soils. However, strategies for the reduction of costs of biochar production and application to increase the material's use efficiency need future development. At the same time, policy decision by linking economic benefits with social and environmental issues is necessary for successful implementation of biochar technology in weathered tropical soils. This review recommends that advanced biochar strategies hold potential for sustaining soil quality and agricultural productivity in tropical soils. Refereed/Peer-reviewed

This study aimed at recovering nutrients from human urine as valorized products through chemical and biological mineralization, and assessing their fertilizer potential. Chemosynthesis of struvite (MgNH₄PO₄ ⋅6H₂O) was accomplished from fresh human urine through chemical mineralization using magnesia, whereas biogenic synthesis was achieved through microbial mineralization by employing a wastewater bacterium (Pseudomonas aeruginosa KUJM KY355382.1). Elemental analysis and other characterization results confirmed the synthesized products as struvite under both chemical and biological synthesis methods. The potential of the chemogenic and biogenic struvite products as slow release fertilizer was reflected in improved plant growth characteristics, including height, fresh weight, dry weight, pod length and seed yield, of cowpea (Vigna unguiculata) compared to the control set. Specially, the seeds obtained per plant were 137.71 and 125.14% higher after application of chemogenic and biogenic struvite, respectively, compared to a no-fertilizer control. When assessing aging effect on struvite’s chemical structure by comparing a 15-year old struvite crystal with the recently synthesized biomineral, the weathered struvite was found to lose NH_4^+ however, retain PO_4^(3-) and Mg^(2+), implying its phosphate supplying potential over a long period. Both the chemogenic and biogenic synthesis routes successfully converted human urine to fertilizer (‘waste into wealth’), but the struvite yield was higher in the case of chemogenic synthesis using magnesia (474 ± 9.64 mg L^−1) than biogenic synthesis employing Pseudomonas aeruginosa KUJM (345 ± 6.08 mg L^−1). Still, the biogenic synthesis is preferred over the chemogenic route because the process is more eco-friendly. Refereed/Peer-reviewed

Heavy metals (HMs) are non-biodegradable and persistent contaminants generated from diverse anthropogenic activities and discharged into the environment often via wastewater. HMs can cause toxicity to living organisms including human beings. The conventional environmental technologies such as electrolytic technologies, ion exchange, precipitation, chemical extraction, hydrolysis, polymer microencapsulation used for removal of HMs from wastewater are considered energy intensive and costly. Since several microalgae are endowed with the capability of removing HMs, they are considered as efficient biological agents for their environmental clean-up. Additionally, several microalgae show excellent ability of carbon sequestration, which draws attention of the scientists in reducing carbon dioxide concentration in the environment, and thereby combating global warming and climate change. Biological carbon sequestration using microalgae can offer a sustainable, ecofriendly and cost-effective approach, which has significant advantages over physical, chemical, and geoengineering approaches such as biomass burial, artificial capture, and sequestration of industrially produced CO2 using subsurface saline aquifers, reservoirs, ocean storage, underground storage in depleted oil and gas reservoirs, saline formations or deep, unminable coal beds, stratospheric aerosol injection, marine cloud brightening, cirrus cloud thinning, ground-based albedo modification for managing solar radiation. In this situation, phycoremediation technologies are seen as the most ecofriendly, efficient and suitable technologies for HM removal from wastewater. Numerous photosynthetic microalgae are not only able to remediate the toxic contaminants but also serve as agents of carbon capture from the environment. The present book chapter will deal with the unique potential of some microalgae like Scenedesmus spp., Chlorella spp., and Spirulina spp. for multiple environmental remediations based on coupled carbon sequestration and HM removal processes.

The emergence of novel respiratory disease (COVID-19) caused by SARS-CoV-2 has become a public health emergency worldwide and perturbed the global economy and ecosystem services. Many studies have reported the presence of SARS-CoV-2 in different environmental compartments, its transmission via environmental routes, and potential environmental challenges posed by the COVID-19 pandemic. None of these studies have comprehensively reviewed the bidirectional relationship between the COVID-19 pandemic and the environment. For the first time, we explored the relationship between the environment and the SARS-CoV-2 virus/COVID-19 and how they affect each other. Supporting evidence presented here clearly demonstrates the presence of SARS-CoV-2 in soil and water, denoting the role of the environment in the COVID-19 transmission process. However, most studies fail to determine if the viral genomes they have discovered are infectious, which could be affected by the environmental factors in which they are found.The potential environmental impact of the pandemic, including water pollution, chemical contamination, increased generation of non-biodegradable waste, and single-use plastics have received the most attention. For the most part, efficient measures have been used to address the current environmental challenges from COVID-19, including using environmentally friendly disinfection technologies and employing measures to reduce the production of plastic wastes, such as the reuse and recycling of plastics. Developing sustainable solutions to counter the environmental challenges posed by the COVID-19 pandemic should be included in national preparedness strategies. In conclusion, combating the pandemic and accomplishing public health goals should be balanced with environmentally sustainable measures, as the two are closely intertwined.