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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.

Polycyclic aromatic hydrocarbons (PAHs) are persistent toxic substances that have ubiquitous presence in water, air, soil, and sediment environments. The growth of PAH toxicities and related ecotoxicology risk in estuary sediment has a serious concern. Present study examined the PAHs concentration, sources, and ecological risk from selected sites in Subarnarekha River estuary (SRE) sediment deposits. The sum of toxic 16 PAHs was ranged from 36.8 to 670.8 ng/g (mean = 223.46 ± 196.35 ng/g). The total PAH concentration varied significantly among the sampling sites (range 511.3 ng/g to 233.8 ng/g) based on allochthonous contaminant loads. Among the 16 compounds, Phen had the highest concentration (40.18 ng/g), followed by Pye (31.86 ng/g), Flur (29.36 ng/g), and NA (19.33 ng/g). Most of the sampling sites contained abundant 3-ring and 4-5-ring PAHs. Based on diagnostic ratios and PCA analysis petroleum combustion, biomass, and coal-burning have been identified as the major sources. The PAHs had high mutagenic equivalent factor and toxic equivalent factor values posing great ecological threats and health risks.

OBJECTIVE: With the nationwide lockdown in India, and with a near-exclusive focus on the novel coronavirus disease (COVID-19) there has been a great deal of neglect in the management of other illnesses leading to significant mortality and morbidity. We aimed to assess the feasibility of keeping obstetrics & gynecology services in a secondary care hospital functioning (in terms of regional experiences and comprehensive patient care measures) in the COVID-19 pandemic situation using a clinical approach. STUDY DESIGN: All policies of the World Health Organization and other international obstetrics- gynecological recommendations or guidelines were followed in keeping the services functional. Hospital data of obstetrics and gynecology services were maintained and compared with the previous year’s data of the corresponding period (January to December) through a retrospective observational study. RESULTS: Compared to figures for 2019, in-patient admissions, surgeries, and daycare procedures performed, and deliveries conducted were reduced in total but almost approached previous levels. The number of out-patient attendance and gynecologic laparoscopic surgeries were significantly reduced mostly in the initial month of lockdown (April 2020) and thereafter. Only limited COVID-19 testing was done and there was no mortality in patients or health care workers (HCW) in the obstetrics and gynecological department. CONCLUSION: COVID-19 pandemic had caused an unprecedented global healthcare crisis. The experience and data collected from our hospital in the study period validate the ‘clinical’ working protocol that enables comprehensive maternity and gynecology care at secondary level care centers even in a pandemic situation without adverse outcomes on patients or the hospital staff.

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.

Pedicle screw-rod insertion is a common surgical procedure used for treating degenerative spinal diseases. Optimized design of such implants is necessary to avoid undue strains at the bone–implant interface. In this work, ideal optimized implant design is defined as one for which the strain difference between intact bone and bone after implantation at six interfacial positions is zero. To achieve this, genetic programming (GP) based symbolic regression (SR) metamodels are built from limited data obtained from expensive but highly accurate finite element (FE) models. The FE models are generated from CT scan data. A cumulative objective function is expressed in terms of GP-based SR metamodels which is then combined with a genetic algorithm (GA) to predict patient-specific optimum implant designs.

Arsenic (As) is a toxic metalloid associated with various negative human health impacts including cancer, skin lesions, cardiovascular diseases, and diabetes. Arsenic contamination of groundwater and soil is a major human health issue, particularly in South and Southeast Asia. Use of As-contaminated groundwater from shallow tube wells for irrigation of paddy rice, the staple food for people in this region, is one of the causes of As-related health impacts. The anaerobic growing conditions of flooded rice paddies and the unique physiology of the rice plants lead to increased As levels in rice. The World Health Organization (WHO) has set advisory levels of As in polished (i.e., white) rice grain at 0.2 mg/kg, but the EU and USA are yet to set legal standards for As in rice and rice-based products. Strategies for lowering As accumulation in rice revolve around two approaches—agronomic and biotechnological. Agronomic approaches, such as mineral supplementation of soil using iron, phosphorus, sulfur, silicon, water management, soil aeration practices, and the use of biological agents, are designed to lower As solubility, and uptake by rice. Rotation of the rice crop with As accumulating plants could also result in lowering soil As. Biotechnological approaches involve producing transgenic rice varieties by altering the expression of genes involved in As uptake, translocation, and sequestration in the plant. These approaches, combined with proper diet management and creating public awareness on potential health risks resulting from chronic exposure to As in rice, could play a key role in risk reduction.

Pharmaceutical and personal care products (PPCPs) are considered as emerging contaminants (ECs) in the environment due to their known or suspected adverse ecological effects and human health risks....

Salinity and acidity have affected several hundred million hectares of land throughout the globe which poses a major threat to global food security and biodiversity. Application of organic amendments for salt-affected soils has been identified as one of the most effective ways to mitigate salinity-induced problems and considered as a green technique offering twin benefits of waste load reduction and land reclamation. However, studies on reclaiming acidic-salt affected soils are limited. Therefore, this study aimed to determine the reclamation potential of biochars and organic amendments involving Gliricidia sepium biochar produced at 300 °C, 500 °C, and 700 °C, green waste compost, and municipal sewage sludge at three different amendment ratios, 1.0%, 2.5% and 5.0%. The incubation experiment was conducted for a 4-month period with different amendment ratios applied to the coastal acidic-salt affected soil. Subsamples were extracted from incubation pots after 1 and 4 months and analyzed for soil chemical parameters (pH, EC, NO3−, PO43−, total organic carbon, cation exchange capacity, sodium adsorption ratio, exchangeable sodium percentage) and microbial enzyme activity (catalase activity, and acid- and alkaline phosphatase activity). All organic amendments demonstrated enhancement of the soil properties in a significant manner. However, increasing incubation time and amendment ratio increase the changes of soil parameters by a great percentage. Therefore, the maximum amendment ratio of 5.0% and 4 months of incubation period rendered a significant improvement in the reclamation of acidic-salt affected soil. However, the biochar produced at 500 °C contributed the maximum towards the improved physicochemical and biochemical profile of acidic-salt affected soil, making it the most promising organic amendment for the reclamation of acidic-salt affected soil. The overall reclamation efficiency of organic amendments registered the following order of variation: 700 BC

Different stabilization devices have been used for treating lumbar spine disorders, including fusion, dynamic stabilization devices, flexible rods etc., which possess a different level of limitations. A simple experimental procedure is developed using a prototype lumbar spine specimen (L1-S), to evaluate the biomechanical performance of the lumbar spine. The range of motions (ROM) are tested for pedicle screw made of stainless steel (SS) fixation, using Teflon rod, ultra high molecular weight poly ethylene (UHMWPE) rod, poly ether ether ketone (PEEK) rod and SS flexible rod device (FRD). SS pedicle screw is used for fixation on the prototype lumbar spine. Experimental results are validated and compared with finite element (FE) results. It is observed that, in both flexion and extension, reduction in ROM is higher for Teflon and UHMWPE as compared to PEEK and FRD system. Differences between experimental and numerical results are found to be within an acceptable limit of 5–11%. For flexibility study, both numerical and experimental results support that PEEK rod plays an effective and important role among all the semi-rigid rods. The FRD devices are found to preserve the flexibility of the segment considerably better than PEEK rod.

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.

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