Based on epidemiological parameter data, probe into a stochastically perturbed dominant variant of the COVID-19 pandemic model

During the COVID-19 pandemic, the SARS-CoV-2 gene mutation has been rapidly emerging and spreading all over the world. Experts worldwide regularly monitor genetic mutations and variants through genome-sequence-based surveillance, laboratory testing, outbreak investigation, and epidemiological probing. Clinical pathologists and medical laboratory scientists prefer developing or endorsing COVID-19 vaccines with a broader immune response involving various antibodies and cells to protect against mutations or new variants. Randomness plays an enormous role in pathology and epidemiology. Hence, based on epidemiological parameter data, we construct and probe a stochastically perturbed dominant variant of the coronavirus epidemic model with three nonlinear saturated incidence rates. We reveal the existence of a unique global positive solution to the constructed stochastic COVID-19 model. The Lyapunov function method is used to determine the presence of a stationary distribution of positive solutions. We derive sufficient conditions for the coronavirus to be eradicated. Eventually, numerical simulations validate the effectiveness of our theoretical outcomes.

Acoustic Droplet Vaporization of Perfluorohexane Emulsions Induced by Heterogeneous Nucleation at an Ultrasonic Frequency of 1.1 MHz

Droplets made of liquid perfluorocarbon undergo a phase transition and transform into microbubbles when triggered by ultrasound of intensity beyond a critical threshold; this mechanism is called acoustic droplet vaporization (ADV). It has been shown that if the intensity of the signal coming from high ultrasonic harmonics are sufficiently high, superharmonic focusing is the mechanism leading to ADV for large droplets (>3 μm) and high frequencies (>1.5 MHz). In such a scenario, ADV is initiated due to a nucleus occurring at a specific location inside the droplet volume. But the question on what induces ADV in the case of nanometer-sized droplets and/or at low ultrasonic frequencies (<1.5 MHz) still remains. We investigated ADV of perfluorohexane (PFH) nano- and microdroplets at a frequency of 1.1 MHz and at conditions where there is no superharmonic focusing. Three types of droplets produced by microfluidics were studied: plain PFH droplets, PFH droplets containing many nanometer-sized water droplets, and droplets made of a PFH corona encapsulating a single micron-sized water droplet. The probability to observe a vaporization event was measured as a function of acoustic pressure. As our experiments were performed on droplet suspensions containing a population of monodisperse droplets, we developed a statistical model to extrapolate, from our experimental curves, the ADV pressure thresholds in the case where only one droplet would be insonified. We observed that the value of ADV pressure threshold decreases as the radius of a plain PFH droplet increases. This value was further reduced when a PFH droplet encapsulates a micron-sized water droplet, while the encapsulation of many nanometer-sized water droplets did not modify the threshold. These results cannot be explained by a model of homogeneous nucleation. However, we developed a heterogeneous nucleation model, where the nucleus appears at the surface in contact with PFH, that successfully predicts our experimental ADV results.

Pericardial Effusion as the Initial Presentation of Systemic Lupus Erythematosus in a 37-Year-Old Female

Systemic lupus erythematosus (SLE) is a complex autoimmune disease that can affect various organs and systems in the body, leading to a wide range of clinical manifestations. Pericardial effusion, which is an accumulation of excessive fluid in the pericardial sac surrounding the heart, can be one of the early presentations of SLE in some individuals. When it occurs in young females, it can be particularly concerning, as SLE predominantly affects women of childbearing age. In this case report, we describe pericardial effusion as the initial presentation of SLE in a 37-year-old mother of four children. Importantly, early diagnosis and consistent follow-up are critical for improving the prognosis and quality of life for individuals with SLE.

In vitro anti-prostate adenocarcinoma and lung cancer studies of phenoxyaniline-block-poly(methyl methacrylate) based nanocomposites via controlled radical polymerization

A phenoxyaniline-based macroinitiator is utilized for the first time in order to produce phenoxyaniline-block-poly(methyl methacrylate) composites through single electron transfer-living radical polymerization (SET-LRP) under mild conditions. A different weight percentage of Cloisite 93A is added into the polymer mixtures in order to increase their biochemical properties. The prepared block copolymer nanocomposites are characterized using ATR-IR, UV-vis-spectroscopy, XRD, Raman, TGA, DSC, a particle size analyzer, contact angle measurements and SEM in order to characterize their structural, thermal, surface and morphological properties. Further, the developed polymeric nanocomposites are successfully applied in two different cancer cell lines (prostate adenocarcinoma and lung cancer), which show excellent anticancer properties. Also, acridine orange/ethidium bromide (AO/EtBr) dual staining is performed, which causes drastic cell death by apoptosis in both A549 and PC-3 cell lines, which indicated that the prepared polymeric nanocomposites effectively inhibit the cell proliferation and induce the apoptosis in both the cancer cells. Here nanoclay is used for cancer treatment because of its complete water solubility, which essentially causes the formation of a cationic complex between the clay and drug through electrostatic interactions. Hence, the exchange of ions between the clay and other ions in the biological environment leads to inhibition of the proliferation of prostate adenocarcinoma and lung cancer cells in the system.

N-Nitrosamine sensing properties of novel penta-silicane nanosheets-a first-principles outlook

CONTEXT

N-Nitrosamine is one of the highly toxic carcinogenic compounds that are found almost in the entire environment. In the present work, novel penta-silicene (penta-Si) and penta-silicane (penta-HSi) are utilised to sense the N-nitrosamine in the air environment. Initially, structural firmness of penta-Si and penta-HSi is confirmed using cohesive energy. Subsequently, the electronic properties of penta-Si and penta-HSi are discussed with the aid of electronic band structure and projected density of states (PDOS) maps. The calculated band gap of penta-Si and penta-HSi is 0.251 eV and 3.117 eV, correspondingly. Mainly, the adsorption property of N-nitrosamine on the penta-Si and penta-HSi is studied based on adsorption energy, Mulliken population analysis along with relative energy gap changes. The computed adsorption energy range is in physisorption (- 0.101 to - 0.619 eV), which recommends that the proposed penta-Si and penta-HSi can be employed as a promising sensor to detect the N-nitrosamine in the air environment.

METHODS

The structural, electronic and adsorption behaviour of N-nitrosamine on penta-Si and penta-HSi are studied based on the density functional theory (DFT) approach. The hybrid generalized gradient approximation (GGA) with Becke's three-parameter (B3) + Lee-Yang-Parr (LYP) exchange correlation functional is used to optimise the base material. All calculations in the present work are carried out in Quantum-ATK-Atomistic Simulation Software.

Demographic Characteristics and Disease Pattern Among Non-COVID-19 Patients Admitted to Medical Units of a Tertiary Care Hospital in Sri Lanka During Lockdown of the COVID-19 Pandemic: A Comparison During and Before Lockdown

BACKGROUND

The COVID-19 infection was rapidly spreading almost all over the world, and the first case was confirmed on 27th January 2020 by a foreign tourist in Sri Lanka. The first Sri Lankan citizen with COVID-19 was confirmed on 11th March 2020. Soon after the confirmation of the disease, long days of lockdown were imposed in almost all parts of the world, including Sri Lanka, to control the spread of the disease.  Objectives: To determine the demographic characteristics such as age, sex, number of patients, and disease pattern among non-COVID-19 patients admitted to the medical units during the lockdown of the COVID-19 pandemic and to compare these characteristics with the data before the lockdown.

METHODS

This was a cross-sectional analytical study. It was conducted at the Teaching Hospital in Batticaloa, Sri Lanka. All the non-COVID-19 patients admitted to medical wards and intensive care units (ICU) were included in this study. Patients admitted to the medical intensive care unit (MICU) and coronary care unit (CCU) were considered ICU admissions in this study. They were studied over a period of one month during lockdown (11th March 2020 to 10th April 2020) and compared with the patients admitted one month prior to the lockdown (11th February 2020 to 10th March 2020).

RESULTS

Totally, 2340 non-COVID-19 patients (52.5% males) were admitted before the lockdown, and 1376 non-COVID-19 patients (56.2% males) were admitted during the lockdown. This reduction in admission is statistically significant (p-value is <0.001, df=3715). Patients admitted to the wards before lockdown were 2283 (97.6%) and during lockdown were 1309 (95.1%). ICU admissions were N=57 (2.4%) before lockdown and N=67 (4.9%) during lockdown. The common age distribution before the lockdown showed that 26.4% were 31-50 and 41.5% were 51-70 years. Similarly, during lockdown, the age distribution disclosed that 28.9% were 31-50 years and 42.9% were 51-70 years. The disease pattern demonstrated that before lockdown, the majority of patients were admitted for routine hemodialysis (13.2%), to get an injection (9.9%), ischemic heart disease (8.4%), chronic kidney disease (7.3%), and viral fever, including dengue (7.2%). Likewise, during lockdown, more patients were admitted for routine hemodialysis (10.7%), viral fever, including dengue (9.3%), ischemic heart disease (8.8%), to get an injection (8.5%), and chronic kidney disease (5.9%).  Conclusion: There was a significant reduction in the number of non-COVID-19-related admissions during the period of lockdown. However, there was not much difference in the proportion of admissions according to gender, age, and disease pattern before and during lockdown. More number of male patients were admitted than female patients. Most of the admitted patients were under the age group of 51-70 years. The highest number of patients were admitted for routine hemodialysis before and during lockdown. However, a slightly higher number of patients were admitted to the ICU during lockdown. Therefore, strengthening the ICU facilities may be an important preparation to accommodate more patients in the future if a similar kind of emergency lockdown occurs in a pandemic situation. In addition, admissions due to non-communicable diseases (NCD) didn't fall in proportion during the pre-COVID-19 period and the lockdown period. Therefore, the redistribution of healthcare facilities needs to be done wisely to face the challenges caused by the NCDs.

A Case Report on Generalised Muscle Spasms After Ornamental Tarantula Bites That Responded Well to Intravenous Calcium Gluconate Treatment

Here, we present a case of a 55-year-old male, who was admitted with a spider bite, which caused swelling of the hand and painful muscle spasms along with palpitations. The patient made a complete recovery after the administration of intravenous calcium gluconate, followed by oral calcium supplements. Although no specific treatment exists in Sri Lanka for spider bites, calcium supplements can be beneficial for Sri Lankan ornamental tarantula (Poecilotheria fasciata) bites.

Starvation Ketoacidosis in a Young Healthy Female After Prolonged Religious Fasting

Ketone bodies are important energy sources for the body and are produced by the liver when the body is in a deficiency state of glucose, which is used in the peripheral tissues to provide energy. There are several ketone bodies that are produced by the liver, of which two are important: acetoacetate and beta-hydroxybutyrate. Even though ketone bodies are always present in the body, they are minimal when a person is not fasting. Ketone bodies are produced by the oxidation of fatty acids to fulfill the metabolic needs of tissues, especially the brain. The biochemical reactions of forming ketone bodies are triggered by a lack of insulin and an elevated glucagon level in the blood. Both cause unopposed lipolysis and free fatty acid oxidation resulting in the production of ketone bodies and eventually high anion gap metabolic acidosis. We present a case of young healthy female who presented with euglycemic ketoacidosis after involving prolonged fasting for her religious ceremony. She also physically exerted quite more during her fasting. With a detailed history and excluding other possibilities, we made the diagnosis of starvation ketoacidosis. She improved well with the treatment and established her pre-morbid condition in our review.

A Probable Association of Aseptic Meningoencephalitis, Complicated With Cerebral Salt Wasting Syndrome Following COVID-19 Vaccination: A Case Report

Coronavirus disease-19 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occurred worldwide, and it affected millions of people around the world and killed millions of lives without a definitive treatment. During this challenging time, vaccine production has been hugely carried out leading to the invention of many vaccines against COVID-19. As any vaccine can have some side effects, COVID-19 vaccines also need surveillance and reporting side effects worldwide. Currently, more than 10 vaccines are available against SARS-CoV-2 infection globally. There are many neurological complications reported by SARS-CoV-2 vaccines. There are some reported neurological complications, such as ischemic stroke, Guillain-Barré syndrome, transverse myelitis, Bell's palsy, cerebral venous sinus thrombosis, optic neuritis, meningoencephalitis, small fiber neuropathy, and Tolosa-Hunt syndrome. We present a case of an elderly man who presented with fever, fits, hyponatremia, and polyuria following COVID-19 vaccination and was found to have cerebral salt wasting (CSW) with the exclusion of other causes.

Anthropogenic marine litter: An approach to environmental quality for India's southeastern Arabian Sea coast

Anthropogenic marine litter (AML), mainly plastic, is a global concern that is persistent and widespread. To prevent and mitigate this threat, we need to understand the magnitude and source of AML. There is limited knowledge about AML pollution on the Indian Coast. In this context, the present study examined the distribution, abundance, typology, and beach quality based on AML along 22 beaches on the southeastern coast of the Arabian Sea. A total of 4911 AML items were classified into 9 categories, weighing 16.79 kg, and retrieved from a total area of 8000 m². The mean abundance and weight of AML in the current study were 0.45 ± 0.34 items/m² and 1.53 ± 0.92 g/m², respectively. Thottapally showed the most abundant AML among the studied beaches with 0.96 items/m², followed by Azheekkal with 0.73 items/m². Plastic, being the most common item, accounts for 77.6 % of all items and has a mean density of 0.35 items/m² comprising hard plastic (22 %), thermocol (13 %), food wrappers (7 %), cigarette butts (7 %), plastic rope (6 %), and plastic cutlery (6 %). Hazardous anthropogenic litter (HAL) was maximum at Thottapally (17.71 %; 85 out of 480 items collected). Based on the cleanliness of beaches, they are graded "moderately clean" (63 %) by the General Index (GI), "clean" (54 %), and "moderately clean" (40 %) as calculated by the Clean Coast Index (CCI). Hazardous Anthropogenic Beach Litter Index (HABLI) classifies 72 % of beaches as "moderately safe", while the Environmental Status Index (ESI) rates 68 % of beaches as "mediocre". Besides, model simulations demonstrated the pathways of AML propagation, which correlate to the littoral and coastal current flow patterns over the region. Land-based activities were the crucial factors influencing AML distribution. The study highlighted the need for effective regional litter management strategies, policy instruments for the litter impact pathways, economic, regulatory, and behavioural management tools, which were also discussed.

Facile Synthesis of Battery-Type CuMn2O4 Nanosheet Arrays on Ni Foam as an Efficient Binder-Free Electrode Material for High-Rate Supercapacitors

The development of battery-type electrode materials with hierarchical nanostructures has recently gained considerable attention in high-rate hybrid supercapacitors. For the first time, in the present study novel hierarchical CuMn₂O₄ nanosheet arrays (NSAs) nanostructures are developed using a one-step hydrothermal route on a nickel foam substrate and utilized as an enhanced battery-type electrode material for supercapacitors without the need of binders or conducting polymer additives. X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques are used to study the phase, structural, and morphological characteristics of the CuMn₂O₄ electrode. SEM and TEM studies show that CuMn₂O₄ exhibits a nanosheet array morphology. According to the electrochemical data, CuMn₂O₄ NSAs give a Faradic battery-type redox activity that differs from the behavior of carbon-related materials (such as activated carbon, reduced graphene oxide, graphene, etc.). The battery-type CuMn₂O₄ NSAs electrode showed an excellent specific capacity of 125.56 mA h g^-1 at 1 A g^-1 with a remarkable rate capability of 84.1%, superb cycling stability of 92.15% over 5000 cycles, good mechanical stability and flexibility, and low internal resistance at the interface of electrode and electrolyte. Due to their excellent electrochemical properties, high-performance CuMn₂O₄ NSAs-like structures are prospective battery-type electrodes for high-rate supercapacitors.

Protein-Losing Enteropathy as the First Presentation of Systemic Lupus Erythematosus in a Resource-Limited Setting in Sri Lanka: A Case Report

Protein-losing enteropathy (PLE) is one of the rare gastrointestinal manifestations of systemic lupus erythematosus (SLE), which can manifest several years before the diagnosis of SLE. PLE should be suspected in patients with hypoalbuminemia in the absence of urinary protein loss and normal liver functions without any other manifestations of malnutrition. Due to the non-specificity of the imaging and histological findings, it is difficult to diagnose PLE in resource-limited settings. Thus, it is underdiagnosed. We report the case of a 38-year-old Sri Lankan (South Asian) female who is a diagnosed patient with hypothyroidism and has presented with worsening generalized body swelling and ascites for two months. She had hypoalbuminemia without proteinuria. Thus, the clinical diagnosis of PLE was suspected. The diagnosis of SLE was suspected because of significant alopecia, high titer (1:1000) antinuclear antibody (ANA) positivity, and hypocomplementemia. Though confirmatory tests such as Tc-99 albumin scintigraphy and stool alpha-1 anti-trypsin were not available in our resource-limited setting, the diagnosis of the SLE-associated protein-losing enteropathy was made as the patient fulfilled the European Alliance of Associations for Rheumatology (EULAR) criteria for SLE and also by excluding all the other possible causes of PLE.

Interspecific variations in leaf litter decomposition and nutrient release from tropical mangroves

Efficient nutrient cycling through decomposition of leaf litter often regulates the high productivity and subsequent carbon sequestration of mangrove ecosystems along the land-ocean boundary. To understand the characteristics and the potentials of mangrove leaf litter in supplying organic carbon and nutrients to the coastal waters, four major mangrove species (A. officinalis, R. mucronata, H. littoralis and S. apetala) of Bhitarkanika mangrove forest, Odisha, India, were examined in controlled environmental conditions. Half-life time (t₀.₅), estimated for decomposition of those mangrove leaf litter materials ranged from 18 to 52 days. During the incubation experiment, organic carbon from mangrove leaf litter was released primarily through physical processes and was available for heterotrophic respiration. Among the four species, leaf litter of S. apetala with the lowest initial C/N ratios, released organic carbon with low molecular weight (labile substances) that has a relatively higher potential to support the aquatic food web. On the contrary, leaf litter of R. mucronata released organic material with relatively higher molecular weight (humic substances, higher aromaticity), which revealed its superior non-labile characteristics in this unique environment. The mean total heterotrophic bacterial (THB) population in the incubation was around nine-fold higher than the control. THB population growth and Chromophoric Dissolved Organic Matter (CDOM) spectral data further suggested the rapid release of highly labile and recalcitrant carbon from S. apetala and R. mucronata (between 7th and 21st day of incubation), respectively. The mean litter fall from the Bhitarkanika mangrove forest was estimated to be 11.32 ± 1.57 Mg ha^-1 y^-1 and its corresponding carbon content was 5.43 ± 0.75 Mg C ha^-1. The study revealed the role of leaf litter leachates as an important food source to microbial communities in the adjacent coastal waters, in addition to a potential carbon sequesterer through long-term burial in mangrove soil and export to the deep sea.

Case report on pre-orthodontic trainer in a 9-year-old child with 12 months follow up

BACKGROUND: Pre-fabricated myofunctional appliances for early orthodontic therapy have been designed specifically for the care of children at the time of mixed dentition in growing adolescents with class II division 1 malocclusions. Sophisticated prefabricated removable functional appliances known as pre-orthodontic trainers have been shown to train the orofacial musculature, thus correcting malocclusions. CASE DESCRIPTION: This is a case report of 9-year-old boy diagnosed as Class II division 1 malocclusion with protruded upper anterior teeth, constricted upper arch, space loss in lower arch and Class 2 molar relation on side. Functional treatment approach was decided using pre orthodontic T4K trainer for 12 months. At the end of this phase of treatment, improvements have been evaluated with lateral cephalograms superimposition between T1 and T2. DISCUSSION: Class II orthopaedic treatment along with the use of functional appliances by early interception assist in addressing the concerns with soft tissues, muscles, mouth respiration, and bruxism. The pre orthodontic trainer allowed a good dento-skeletal result as it had a major effect on the masticatory muscles after 12 months application which helped in obtaining a good esthetic outcome for the patient. CONCLUSIONS: The use of prefabricated functional appliance in children can be an advantageous method for early treatment of class II malocclusions with functional patterns as these devices influences masticatory muscle which help in molding the facial tissues and a viable alternative to braces for treating malocclusions in children because it stimulates the development of the dental arches transversely to stop the progression of the malocclusion. Therefore, when a lack of transverse development is discovered at a young age, this appliance is an invaluable tool for enhancing dental arch development, interceptive management of malocclusion, and oral habits.

Networking and co-occurrence of virulent and multidrug resistant environmental bacteria in different aquatic systems: A gap in MDR-virulence transfer?

Co-occurrence of resistance and virulence is often overlooked in aquatic bacteria as environmental reservoirs, while transmission of these characteristics to clinically significant strains present unforeseen problems in future. In this investigation, environmental bacteria identified concurrently from multiple aquatic habitats viz., groundwater, canal, river and coastal waters were profiled for antibiotic resistance, metal tolerance, virulence factors and genes coding for these determinants. Strains from polluted river and canal exhibited higher resistance and virulence, especially Pseudomonas gessardii and P. fluorescens displayed high antibiotic resistance index (ARI > 0.6-0.8) with Alkaline Protease and Phospholipase production. Opportunistic pathogens including Vibrio parahaemolyticus, V. alginolyticus, V. vulnificus, Corynebacterium and Comamonas testosteroni expressed all three virulence factors with relatively low resistance. However, V. vulnificus and V. alginolyticus exhibited multiclass antibiotic resistance (5/6 classes). Metagenomic analysis revealed that genes corresponding to beta-lactam resistance were significantly higher (p < 0.05) in freshwater than seawater, while multidrug resistance gene were higher (p < 0.05) in seawater. In all aquatic bodies, abundant virulence genes belonged to secretion system proteins followed by motility related genes. Culturable bacteria revealed differential distribution of positive and negative correlation between 31 targeted genes with expressed resistance and virulence. Among Acinetobacter, significant positive correlation was found between Phospholipase production, other virulence genes (OVGs) and resistance to DNA Synthesis Inhibitors (DSI). In Pseudomonas, positive correlation was detected between toxin genes (toxA, eta, hlyA and stx) and resistance to cell wall synthesis inhibitors (CSI) as well as with OVGs and adhesion genes (eae, afa, papC and papA). Network analysis displayed unique clustering of genes ncc, arsB, strA, merA and intI dominated by non-pathogens and distinct clustering of genes pho, erm, nfsA, trh, lasB, tdh and invA by Vibrio. This investigation extends insight on co-occurring resistance and virulence in aquatic reservoir bacteria that could pose serious threats to public health in future.

Benthic foraminifera as an environmental proxy for pollutants along the coast of Chennai, India

Benthic foraminifera are increasingly used as an indicator of environmental disturbance. Their sensitivities to pollutants can be reflected by changes in assemblage, which can provide useful information about ecosystem health. This study aimed to investigate the impact of organic and inorganic pollutants on the benthic ecology of the Chennai coast, with a focus on the 2017 oil spill caused by the collision of two ships. Sediment samples collected from five distinct zones along the coast were analysed for pollutants such as polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPH), heavy metals (Cr, Cd, Pb) and total organic carbon (TOC). The maximum concentrations of Cr (137 μg/g), Cd (6.93 μg/g) and Pb (34.2 μg/g), as well as TPH (84.3 μg/g) and PAHs (227 ng/g), were observed. A total of 47 species of foraminifera were identified in this study, of which 12 were morphologically abnormal. In the low-impact zone, the species diversity index (H') was higher. TPH and PAH concentrations were positively associated with abnormal species. Pollution-resistant foraminifera species include Ammonia tepida, Elphidium discoidale, and Quinqueloculina lamarckiana, while opportunistic foraminifera include Pararotalia curryi, Nonionella stella, Rosalina globularis, and Spirillina vivipara. PAHs and heavy metals were adversely correlated with foraminiferal abundance, while TPH was positively correlated. To assess the response of the benthic ecosystem to hydrocarbon pollution, indices such as the Foraminiferal Index of Environmental Impact (FIEI), Exponential (H'_bc) index and the Foraminiferal Abnormality Index (FAI) were used as environmental health proxies. FIEI, exp(H'_bc) and FAI values show the impact of hydrocarbon pollution to an extent along the northern Chennai coast.

Hybridization of long short-term memory with Sparrow Search Optimization model for water quality index prediction

Water quality (WQ) analysis is a critical stage in water resource management and should be handled immediately in order to control pollutants that could have a negative influence on the ecosystem. The dramatic increase in population, the use of fertilizers and pesticides, and the industrial revolution have resulted in severe effects on the WQ environment. As a result, the prediction of WQ greatly helped to monitor water pollution. Accurate prediction of WQ is the foundation of managing water environments and is of high importance for protecting water environment. WQ data presents in the form of multi-variate time-sequence dataset. It is clear that the accuracy of predicting WQ will be enhanced when the multi-variate relation and time sequence dataset of WQ are fully utilized. This article presents the Water Quality Prediction utilising Sparrow Search Optimization with Hybrid Long Short-Term Memory (WQP-SSHLSTM) model. The presented WQP-SSHLSTM model intends to examine the data and classify WQ into distinct classes. To achieve this, the presented WQP-SSHLSTM model undergoes data scaling process to scale the input data into uniform format. Followed by, a hybrid long short-term memory-deep belief network (LSTM-DBN) technique is employed for the recognition and classification of WQ. Moreover, Sparrow search optimization algorithm (SSOA) is utilized as a hyperparameter optimizer of the proposed DBN-LSTM model. For demonstrating the enhanced outcomes of the presented WQP-SSHLSTM model, a sequence of experiments has been performed and the outcomes are reviewed under distinct prospects. The WQP-SSHLSTM model has achieved 99.84 percent accuracy, which is the maximum attainable. The simulation outcomes ensured the enhanced outcomes of the WQP-SSHLSTM model on recent methods.

Comparative Evaluation of Fixed Functional Cantilever Space Maintainer and Fixed Nonfunctional Space Maintainer: A Randomized Controlled Trial

Background and objectives

Effective way to prevent mesial drift after the early loss of primary first molars is by inserting a durable space maintainer. Several space maintainers are available; fixed nonfunctional (FNF) space maintainer (crown and loop) is commonly used when abutment teeth need full-coronal restoration. Disadvantages of crown and loop space maintainer are nonfunctional, nonesthetic, and fracture of solder loop. To overcome this drawback, new design of fixed functional cantilever (FFC) space maintainer (crown and pontic) using bis-acrly composite resin. The study evaluated the longevity and acceptance of an FFC and compared it with a FNF space maintainer.

Materials and methods

A total of 20 healthy children, aged 6-9 years, were selected having bilateral premature loss of lower deciduous first molars. FFC space maintainer in one quadrant and FNF space maintainer in the other was cemented. The subject's acceptance of treatment was checked using a visual analog scale after the treatment completion. Criteria for complication leading to the failure was assessed in both the designs in the 3rd, 6th, and 9th month. Cumulative success longevity was obtained at a 9 month evaluation.

Results

Patient acceptability was greater in group I (FFC) in comparison to group II (FNF). In group I, fracture of the crown and pontic was the common complication leading to failure, followed by attrition of the crown and loss of material due to abrasion. In group II, fracture of the solder joint was the common complication leading to failure, followed by slippage of the loop gingivally and cement loss. The longevity of groups I and II were 70 and 85%, respectively.

Conclusion

FFC can be considered a viable alternative to conventional FNF space maintainers.

How to cite this article

Sathyaprasad S, Krishnareddy MG, Vinod V, et al. Comparative Evaluation of Fixed Functional Cantilever Space Maintainer and Fixed Nonfunctional Space Maintainer: A Randomized Controlled Trial. Int J Clin Pediatr Dent 2022;15(6):750-760.

Arsenic resistance and horizontal gene transfer are associated with carbon and nitrogen enrichment in bacteria

Coastal waters are confluences receiving large amounts of point and non-point sources of pollution. An attempt was made to explore microbial community interactions in response to carbon, nitrogen and metal pollution. Additionally, experiments were designed to analyze the influence of these factors on horizontal gene transfer (HGT). Shift in bacterial diversity dynamics by arsenic stress and nutrient addition in coastal waters was explored by metagenomics of microcosm setups. Phylogenetic analysis revealed equal distribution of Gammaproteobacteria (29%) and Betaproteobacteria (28%) in control microcosm. This proportional diversity from control switched to unique distribution of Gammaproteobacteria (44.5%)> Flavobacteria (17.7%)> Bacteriodia (11.92%)> Betaproteobacteria (11.52%) in microcosm supplemented with carbon, nitrogen and metal (C + N + M). Among metal-stressed systems, alpha diversity analysis indicated highest diversity of genera in C + N + M followed by N + M > C+M> metal alone. Arsenic and ampicillin sensitive E. coli XL1 blue and environmental strains (Vibrio tubiashii W85 and E. coli W101) were tested for efficiency of uptake of plasmid (P) pUCminusMCS (arsB^Ramp^R) under varying stress conditions. Transformation experiments revealed that combined effect of carbon, nitrogen and metal on horizontal gene transfer (HGT) was significantly higher (p < 0.01) than individual factors. The effect of carbon on HGT was proved to be superior to nitrogen under metal stressed conditions. Presence of arsenic in experimental setups (P + M, P + N + M and P + C + M) enhanced the HGT compared to non-metal counterparts supplemented with carbon or nitrogen. Arsenic resistant bacterial isolates (n = 200) were tested for the ability to utilize various carbon and nitrogen substrates and distinct positive correlation (p < 0.001) was found between arsenic resistance and utilization of urea and nitrate. However, evident positive correlation was not found between carbon sources and arsenic resistance. Our findings suggest that carbon and nitrogen pollution in aquatic habitats under arsenic stress determine the microbial community dynamics and critically influence uptake of genetic material from the surrounding environment.

Ingestion and toxic impacts of weathered polyethylene (wPE) microplastics and stress defensive responses in whiteleg shrimp (Penaeus vannamei)

Weathered plastic litter is recognized as hazardous secondary microplastics(MPs) in the coastal and marine ecosystems, which are of high concern due to their greater impact on the environment. The present study aims to elucidate the impacts of environmentally weathered polyethylene (wPE) MPs on ingestion, growth and enzymatic responses in Penaeus vannamei. The Penaeus vannamei was chronically exposed to five varying concentration (0.1 mg-0.5 mg) of wPE particles in the size range between 43 and 32 μm for a period of 25days, followed by 5days depuration. At the end of exposure, a considerable number of wPE particles were observed from <2 to 14 per individual organism. However, around 60% of the wPE particles were removed after the depuration phase. The toxic exposure on P. vannamei resulted in significant changes in the enzymatic and growth responses with increasing concentration and duration. In addition, growth assessment confirmed that wPE exposure inhibited the growth of organism, and the effect was particularly evident at increasing concentrations and prolonged exposure. Also observed an elevated levels of lipid peroxidation, glutathione-S-transferases, whereas lower levels of reduced-glutathione and catalase at all exposed concentrations. This study confirmed that the ingestion of wPE was completely influenced by exposure duration, rather than the concentrations of administered. The present biomarker assay might act as an appropriate oxidative stress index for wPE toxicity. Findings of this study is useful in providing the basic biological information for environmental risk assessments of MPs, which are of high concern due to the rising input of microplastics into the environment.