Coronavirus: a comparative analysis of detection technologies in the wake of emerging variants.

An outbreak of the coronavirus disease caused by a novel pathogen created havoc and continues to affect the entire world. As the pandemic progressed, the scientific community was faced by the limitations of existing diagnostic methods. In this review, we have compared the existing diagnostic techniques such as reverse transcription polymerase chain reaction (RT-PCR), antigen and antibody detection, computed tomography scan, etc. and techniques in the research phase like microarray, artificial intelligence, and detection using novel materials; on the prospect of sample preparation, detection procedure (qualitative/quantitative), detection time, screening efficiency, cost-effectiveness, and ability to detect different variants. A detailed comparison of different techniques showed that RT-PCR is still the most widely used and accepted coronavirus detection method despite certain limitations (single gene targeting- in context to mutations). New methods with similar efficiency that could overcome the limitations of RT-PCR may increase the speed, simplicity, and affordability of diagnosis. In addition to existing devices, we have also discussed diagnostic devices in the research phase showing high potential for clinical use. Our approach would be of enormous benefit in selecting a diagnostic device under a given scenario, which would ultimately help in controlling the current pandemic caused by the coronavirus, which is still far from over with new variants emerging.

Can fruit and vegetable aggregation systems better balance improved producer livelihoods with more equitable distribution?

The need for food systems to generate sustainable and equitable benefits for all is a global imperative. However, whilst ample evidence exists linking smallholder farmer coordination and aggregation (i.e. the collective transport and marketing of produce on behalf of multiple farmers) to improved market participation and farmer incomes, the extent to which interventions that aim to improve farmer market engagement may co-develop equitable consumer benefits remains uncertain. This challenge is pertinent to the horticultural systems of South Asia, where the increasing purchasing power of urban consumers, lengthening urban catchments, underdeveloped rural infrastructures and inadequate local demands combine to undermine the delivery of fresh fruits and vegetables to smaller, often rural or semi-rural markets serving nutritionally insecure populations. To this end, we investigate the potential for aggregation to be developed to increase fruit and vegetable delivery to these neglected smaller markets, whilst simultaneously improving farmer returns. Using an innovative system dynamics modelling approach based on an aggregation scheme in Bihar, India, we identify potential trade-offs between outcomes relating to farmers and consumers in smaller local markets. We find that changes to aggregation alone (i.e. scaling-up participation; subsidising small market transportation; mandating quotas for smaller markets) are unable to achieve significant improvements in smaller market delivery without risking reduced farmer participation in aggregation. Contrastingly, combining aggregation with the introduction of market-based cold storage and measures that boost demand improves fruit and vegetable availability significantly in smaller markets, whilst avoiding farmer-facing trade-offs. Critically, our study emphasises the benefits that may be attained from combining multiple nutrition-sensitive market interventions, and stresses the need for policies that narrow the fruit and vegetable cold storage deficits that exist away from more lucrative markets in developing countries. The future pathways and policy options discovered work towards making win-win futures for farmers and disadvantaged consumers a reality.

A critical assay of heavy metal pollution index for the groundwaters of Peenya Industrial Area, Bangalore, India.

Heavy metals, due to their non-biodegradability and tendency to cause detrimental effects in human beings, are considered as the most hazardous and toxic pollutants. The present investigation was taken up to evaluate the heavy metal concentrations in the groundwaters of Peenya Industrial Area in Bangalore. The concentration of six eco-toxic metals such as chromium, copper, cadmium, iron, nickel, and lead were analyzed for 30 groundwater sampling stations in the study area using atomic absorption spectrometer. The concentration of heavy metals followed the order Cr> Fe >Pb>Cu> Ni> Cd. The analysis results have been used to compute two pollution indices in the groundwater, namely heavy metal pollution index and metal index. Heavy metal pollution index is an effective method of rating and ascertaining the water quality with respect to heavy metals. An index value of 100 is considered to be critical, and on the basis of mean concentration, this value in the study area was observed to be 146.32, which is considerably higher than the stipulated critical index value. 63.33% of the groundwater samples are seen to be having an index far above the critical figure of 100. The mean concentration of metal index was 10.36 and it was seen that 46.67% of the groundwater samples fell under the seriously affected category (metal index values above 6). The results not only show that groundwater of the present study is unacceptable for drinking but also clearly indicate the influence of urban, industrial, and agricultural activities on the groundwaters of the said area. This study has massive relevance in designing control measures and action plans for reducing the pollutant influx into the groundwaters. Prompt enforcement of environmental protection laws is needed to prevent continuous pollution of the area. Further, an immediate and sustainable collective action by all stakeholders to control the pollution level is highly recommended, as this issue poses a severe public health threat.

Homology modeling and docking of AahII-Nanobody complexes reveal the epitope binding site on AahII scorpion toxin.

Scorpion envenoming and its treatment is a public health problem in many parts of the world due to highly toxic venom polypeptides diffusing rapidly within the body of severely envenomed victims. Recently, 38 AahII-specific Nanobody sequences (Nbs) were retrieved from which the performance of NbAahII10 nanobody candidate, to neutralize the most poisonous venom compound namely AahII acting on sodium channels, was established. Herein, structural computational approach is conducted to elucidate the Nb-AahII interactions that support the biological characteristics, using Nb multiple sequence alignment (MSA) followed by modeling and molecular docking investigations (RosettaAntibody, ZDOCK software tools). Sequence and structural analysis showed two dissimilar residues of NbAahII10 CDR1 (Tyr27 and Tyr29) and an inserted polar residue Ser30 that appear to play an important role. Indeed, CDR3 region of NbAahII10 is characterized by a specific Met104 and two negatively charged residues Asp115 and Asp117. Complex dockings reveal that NbAahII17 and NbAahII38 share one common binding site on the surface of the AahII toxin divergent from the NbAahII10 one's. At least, a couple of NbAahII10 - AahII residue interactions (Gln38 - Asn44 and Arg62, His64, respectively) are mainly involved in the toxic AahII binding site. Altogether, this study gives valuable insights in the design and development of next generation of antivenom.

The Lγ Phase of Pulmonary Surfactant.

To determine how different components affect the structure of pulmonary surfactant, we measured X-ray scattering by samples derived from calf surfactant. The surfactant phospholipids demonstrated the essential characteristics of the Lγ phase: a unit cell with a lattice constant appropriate for two bilayers, and crystalline chains detected by wide-angle X-ray scattering (WAXS). The electron density profile, obtained from scattering by oriented films at different relative humidities (70-97%), showed that the two bilayers, arranged as mirror images, each contain two distinct leaflets with different thicknesses and profiles. The detailed structures suggest one ordered leaflet that would contain crystalline chains and one disordered monolayer likely to contain the anionic compounds, which constitute ∼10% of the surfactant phospholipids. The spacing and temperature dependence detected by WAXS fit with an ordered leaflet composed of dipalmitoyl phosphatidylcholine. Physiological levels of cholesterol had no effect on this structure. Removing the anionic phospholipids prevented formation of the Lγ phase. The cationic surfactant proteins inhibited Lγ structures, but at levels unlikely related to charge. Because the Lγ phase, if arranged properly, could produce a self-assembled ordered interfacial monolayer, the structure could have important functional consequences. Physiological levels of the proteins, however, inhibit formation of the Lγ structures at high relative humidities, making their physiological significance uncertain.

In vitro efficacy and in silico analysis of cefixime-ofloxacin combination for Salmonella Typhi from bloodstream infection.

AIMS: Recently, the cefixime-ofloxacin combination is approved by Drug Controller General of India to treat typhoid fever. We sought to evaluate the antimicrobial activity of cefixime-ofloxacin combination against Salmonella Typhi. METHODS AND RESULTS: A total of 283 nonduplicate S. Typhi isolates collected during 2012-2014 were included in this study. Minimum inhibitory concentration (MIC) of cefixime and ofloxacin was determined by using broth microdilution method. Combinational testing was performed by using checkerboard assay. In checkerboard assay, synergistic activity was seen in 11% of isolates, while the majority of the isolate showed indifference and none of them showed antagonism. An in silico strategy, an alternative to the animal model, was carried out to understand drug interaction and toxicity. Molecular docking results elucidated that cefixime and ofloxacin are capable of inhibiting the cell wall synthesis and DNA replication, respectively. Computational ADMET analysis showed no toxicity and no drug-drug interaction between cefixime and ofloxacin. CONCLUSION: Cefixime-ofloxacin combination could be effective against moderately susceptible fluoroquinolone S. Typhi but not fluoroquinolone-resistant isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: Cefixime-ofloxacin combination with no drug-drug interaction and nontoxic predicted through computational analysis did not show antagonism against S. Typhi in in vitro. Although this study showed no adverse effects with the cefixime-ofloxacin combination, further studies on pharmacokinetic and pharmacodynamic (PK-PD) parameters of cefixime and ofloxacin combination are warranted.

Investigations of Magnetic Properties of Oleic Acid and Oleyl Amine Capped Nanostructured Co( x) Ni(1−x) (0.2 ≤ x ≤ 0.8) Alloys.

In this study, nanocrystalline oleic acid and oleyl amine capped Co x Ni1−x alloys (x = 0.2, 0.4, 0.6, 0.8) have been synthesized via chemical reduction route. As-prepared as well as annealed samples were characterized using FTIR spectroscopy, X-ray diffraction and transmission electron microscopy. CoNi alloys were found to be capped with oleic acid-oleylamine complex even after heat treatment up to 400 °BC. XRD patterns confirm that the CoNi alloys crystallize in pure fcc phase with average crystallite sizes in the range of 8­11 nm. TEM micrographs confirm nearly spherical morphologies with narrow particle size distribution of the synthesized CoNi alloys. Average TEM particle sizes range from 7 nm to 12 nm. As-prepared as well as annealed CoNi alloys are ferromagnetic in nature at 298 K. M s values for annealed CoNi alloys are found to be in the range of 25­59.6 emu/g after correction for weight fraction of capped matrix and H c values are in the range of 52­314 Oe. Observed magnetic properties have been interpreted on the basis of size effects, altered crystal anisotropies and spin canting on the surface. FC/ZFC magnetization measurements show magnetic irreversibility and superparamagnetic blocking of nanoparticles due to strong dipolar interactions and particle size distribution. A structure-property correlation in CoNi alloys has been attempted in this investigation.

Hydrophobic surfactant proteins strongly induce negative curvature.

The hydrophobic surfactant proteins SP-B and SP-C greatly accelerate the adsorption of vesicles containing the surfactant lipids to form a film that lowers the surface tension of the air/water interface in the lungs. Pulmonary surfactant enters the interface by a process analogous to the fusion of two vesicles. As with fusion, several factors affect adsorption according to how they alter the curvature of lipid leaflets, suggesting that adsorption proceeds via a rate-limiting structure with negative curvature, in which the hydrophilic face of the phospholipid leaflets is concave. In the studies reported here, we tested whether the surfactant proteins might promote adsorption by inducing lipids to adopt a more negative curvature, closer to the configuration of the hypothetical intermediate. Our experiments used x-ray diffraction to determine how the proteins in their physiological ratio affect the radius of cylindrical monolayers in the negatively curved, inverse hexagonal phase. With binary mixtures of dioleoylphosphatidylethanolamine (DOPE) and dioleoylphosphatidylcholine (DOPC), the proteins produced a dose-related effect on curvature that depended on the phospholipid composition. With DOPE alone, the proteins produced no change. With an increasing mol fraction of DOPC, the response to the proteins increased, reaching a maximum 50% reduction in cylindrical radius at 5% (w/w) protein. This change represented a doubling of curvature at the outer cylindrical surface. The change in spontaneous curvature, defined at approximately the level of the glycerol group, would be greater. Analysis of the results in terms of a Langmuir model for binding to a surface suggests that the effect of the lipids is consistent with a change in the maximum binding capacity. Our findings show that surfactant proteins can promote negative curvature, and support the possibility that they facilitate adsorption by that mechanism.

A compact point-of-use water purification cartridge for household use in developing countries.

Simple, low-cost household interventions are known to be effective in lowering the incidence of waterborne diseases in developing countries. However, high costs along with operational and maintenance issues have prevented the successful adoption of these interventions among the affected communities. To address these limitations, a cost-effective, gravity-driven water purification cartridge has been developed by employing the synergistic disinfection action of low concentrations of silver and chlorine on bacteria and viruses. The silver and chlorine treatment components within the cartridge have been developed using inexpensive materials and integrated with a life indicator and auto-shut-off-mechanism within a compact form factor. The antibacterial as well as antiviral performance of the cartridge was tested by using ground water spiked with Escherichia coli and MS2 bacteriophage. The results show that, although individually, the silver and chlorine treatment systems were unable to inactivate the test strains, the integrated cartridge inactivates both bacteria as well as viruses up to the log reduction requirement of the USEPA guide standard for microbiological water purifiers over its designated life of 2,000 liters.

Diverse role, structural trends, and applications of fluorinated sulphonamide compounds in agrochemical and pharmaceutical fields.

Our knowledge of fluorine's unique and complex properties has significantly increased over the past 20 years. Consequently, more sophisticated and innovative techniques have emerged to incorporate this feature into the design of potential drug candidates. In recent years, researchers have become interested in synthesizing fluoro-sulphonamide compounds to discover new chemical entities with distinct and unexpected physical, chemical, and biological characteristics. The fluorinated sulphonamide molecules have shown significant biomedical importance. Their potential is not limited to biomedical applications but also includes crop protection. The discovery of novel fluorine and Sulfur compounds has highlighted their importance in the chemical sector, particularly in the agrochemical and medicinal fields. Recently, several fluorinated sulphonamide derivatives have been developed and frequently used by agriculturalists to produce food for the growing global population. These molecules have also exhibited their potential in health by inhibiting various human diseases. In today's world, it is crucial to have a steady supply of innovative pharmaceutical and agrochemical molecules that are highly effective, less harmful to the environment, and affordable. This review summarizes the available information on the activity of Fluorine and Sulphonamide compounds, which have proven active in pharmaceuticals and agrochemicals with excellent environmental and human health approaches. Moreover, it focuses on the current literature on the chemical structures, the application of fluorinated sulphonamide compounds against various pathological conditions, and their effectiveness in crop protection.

An anionic phospholipid enables the hydrophobic surfactant proteins to alter spontaneous curvature.

The hydrophobic surfactant proteins, SP-B and SP-C, greatly accelerate the adsorption of the surfactant lipids to an air/water interface. Previous studies of factors that affect curvature suggest that vesicles may adsorb via a rate-limiting structure with prominent negative curvature, in which the hydrophilic face of the lipid leaflets is concave. To determine if SP-B and SP-C might promote adsorption by inducing negative curvature, we used small-angle x-ray scattering to test whether the physiological mixture of the two proteins affects the radius of cylindrical monolayers in the inverse hexagonal phase. With dioleoyl phosphatidylethanolamine alone, the proteins had no effect on the hexagonal lattice constant, suggesting that the proteins fail to insert into the cylindrical monolayers. The surfactant lipids also contain ∼10% anionic phospholipids, which might allow incorporation of the cationic proteins. With 10% of the anionic dioleoyl phosphatidylglycerol added to dioleoyl phosphatidylethanolamine, the proteins induced a dose-related decrease in the hexagonal lattice constant. At 30°C, the reduction reached a maximum of 8% relative to the lipids alone at ∼1% (w/w) protein. Variation of NaCl concentration tested whether the effect of the protein represented a strictly electrostatic effect that screening by electrolyte would eliminate. With concentrations up to 3 M NaCl, the dose-related change in the hexagonal lattice constant decreased but persisted. Measurements at different hydrations determined the location of the pivotal plane and proved that the change in the lattice constant produced by the proteins resulted from a shift in spontaneous curvature. These results provide the most direct evidence yet that the surfactant proteins can induce negative curvature in lipid leaflets. This finding supports the model in which the proteins promote adsorption by facilitating the formation of a negatively curved, rate-limiting structure.

Comparative study of disinfectants for use in low-cost gravity driven household water purifiers.

Point-of-use (POU) gravity-driven household water purifiers have been proven to be a simple, low-cost and effective intervention for reducing the impact of waterborne diseases in developing countries. The goal of this study was to compare commonly used water disinfectants for their feasibility of adoption in low-cost POU water purifiers. The potency of each candidate disinfectant was evaluated by conducting a batch disinfection study for estimating the concentration of disinfectant needed to inactivate a given concentration of the bacterial strain Escherichia coli ATCC 11229. Based on the concentration of disinfectant required, the size, weight and cost of a model purifier employing that disinfectant were estimated. Model purifiers based on different disinfectants were compared and disinfectants which resulted in the most safe, compact and inexpensive purifiers were identified. Purifiers based on bromine, tincture iodine, calcium hypochlorite and sodium dichloroisocyanurate were found to be most efficient, cost effective and compact with replacement parts costing US$3.60-6.00 for every 3,000 L of water purified and are thus expected to present the most attractive value proposition to end users.

Association between obesity and chronic periodontitis: a cross-sectional study.

AIM: Chronic periodontitis is multifactorial and numerous risk factors have been identified to contribute in the disease progression. Current study aimed to conduct a cross-sectional study in a population of patients with cardiovascular diseases in order to correlate the association between obesity [body mass index (BMI) and waist circumference (WC)] and periodontal disease parameters. MATERIALS AND METHODS: The study was of a cross-sectional design and a total of 201 patients were examined after obtaining their informed consent. Subjects who had a history of cardiovascular diseases and under treatment were included in the study. Two indicators of obesity were used: BMI and WC. The following periodontal parameters were assessed: Probing depth, clinical attachment level. The oral hygiene status of the subjects was assessed by the oral hygiene index (OHI, simplified) given by John C Greene and Jack R Vermillion. The influence of the BMI and other confounding variables on periodontitis severity was assessed by multivariate logistic regression analysis. Data were analyzed using SPSS. RESULTS: Significant association was seen with low density lipoproteins (LDL) and severity of periodontitis (p < 0.005), triglyceride levels (TGL) and severity of periodontitis (p < 0.005), cholesterol and severity of periodontitis (p < 0.005), BMI and severity of periodontitis (p < 0.001), OHI and severity of periodontitis (p < 0.001). Significant association was seen with smoking and severity of periodontitis (p < 0.005), BMI and severity of periodontitis (p < 0.001), WC and severity of periodontitis (p < 0.001), cholesterol and severity of periodontitis (p < 0.001), OHI and severity of periodontitis (p < 0.001). CONCLUSION: Obesity has been implicated as a risk factor for several conditions including cardiovascular disease, diabetes, etc. In our study the relation between measures of overall and abdominal obesity (BMI and WC) and periodontal disease showed significant association in the multivariate logistic regression analysis independent of other confounding factors. CLINICAL SIGNIFICANCE: Obesity can act as a significant risk factor in progression of periodontitis.

Integrated point-of-care RT-PCR methods during and after COVID-19 pandemic.

The COVID-19 pandemic has taken the world by surprise and people and organisations worldwide worked in some way or the other to combat the spread; isolate from the infected and get back to normal life, as it was before the pandemic hit. In this regard, the diagnosis of COVID-19 was at the centre of control and prevention and have seen a vehement change in every aspect, especially development of point-of-care testing for better and quick diagnosis. Among different types of techniques developed, the most important was the RT-PCR method of detection which detects nucleic acid of the virus in samples. RT-PCR is a laboratory-based method requiring trained professionals and precise steps for accurate testing. With the advent and spread of the pandemic, number of RT-PCR diagnostic centres rose significantly, and the detection process became less cumbersome, easy to use, ability to handle large volume of samples, more accurate, less time-consuming, and cost-effective. Different industries developed RT-PCR kits, reducing the efforts to prepare laboratory samples. Machines were employed for labour-driven tasks in PCR testing. In addition, new age technologies such as artificial intelligence, IoT, digital systems were combined with RT-PCR for accurate and easy testing. In this review, point-of-care RT-PCR methods, when the COVID-19 started, and the methods now, has been compared on the basis of technological advancements.

Differential effects of the hydrophobic surfactant proteins on the formation of inverse bicontinuous cubic phases.

Prior studies have shown that the biological mixture of the two hydrophobic surfactant proteins, SP-B and SP-C, produces faster adsorption of the surfactant lipids to an air/water interface, and that they induce 1-palmitoyl-2-oleoyl phosphatidylethanolamine (POPE) to form inverse bicontinuous cubic phases. Previous studies have shown that SP-B has a much greater effect than SP-C on adsorption. If the two proteins induce faster adsorption and formation of the bicontinuous structures by similar mechanisms, then they should also have different abilities to form the cubic phases. To test this hypothesis, we measured small-angle X-ray scattering on the individual proteins combined with POPE. SP-B replicated the dose-related ability of the combined proteins to induce the cubic phases at temperatures more than 25 °C below the point at which POPE alone forms the curved inverse-hexagonal phase. With SP-C, diffraction from cubic structures was either absent or present at very low intensities only with larger amounts of protein. The correlation between the structural effects of inducing curved structures and the functional effects on the rate of adsorption fits with the model in which SP-B promotes adsorption by facilitating formation of an inversely curved, rate-limiting structure.

The role of a second diffusing component on the Gill-Rees stability problem.

The stability of natural convection in a vertical porous layer using a local thermal nonequilibrium model was first studied by Rees (Transp Porous Med 87:459-464, 2011) following the proof of Gill (J Fluid Mech 35:545-547, 1969), called the Gill-Rees stability problem. The aim of the present study is to investigate the implication of an additional solute concentration field on the Gill-Rees problem. The stability eigenvalue problem is solved numerically and some novel results not observed in the studies of double-diffusive natural convection in vertical porous (local thermal equilibrium case) and non-porous layers are disclosed. The possibility of natural convection parallel flow in the basic state becoming unstable due to the addition of an extra diffusing component is established. In some cases, the neutral stability curves of stationary and travelling-wave modes are connected to form a loop within which the flow is unstable indicating the requirement of two thermal Darcy-Rayleigh numbers to specify the stability/instability criteria. Moreover, the change in the mode of instability is recognized in some parametric space. The results for the extreme cases of the scaled interphase heat transfer coefficient are discussed.

The accelerated late adsorption of pulmonary surfactant.

Adsorption of pulmonary surfactant to an air-water interface lowers surface tension (γ) at rates that initially decrease progressively, but which then accelerate close to the equilibrium γ. The studies here tested a series of hypotheses concerning mechanisms that might cause the late accelerated drop in γ. Experiments used captive bubbles and a Wilhelmy plate to measure γ during adsorption of vesicles containing constituents from extracted calf surfactant. The faster fall in γ reflects faster adsorption rather than any feature of the equation of state that relates γ to surface concentration (Γ). Adsorption accelerates when γ reaches a critical value rather than after an interval required to reach that γ. The hydrophobic surfactant proteins (SPs) represent key constituents, both for reaching the γ at which the acceleration occurs and for producing the acceleration itself. The γ at which rates of adsorption increase, however, is unaffected by the Γ of protein in the films. In the absence of the proteins, a phosphatidylethanolamine, which, like the SPs, induces fusion of the vesicles with the interfacial film, also causes adsorption to accelerate. Our results suggest that the late acceleration is characteristic of adsorption by fusion of vesicles with the nascent film, which proceeds more favorably when the Γ of the lipids exceeds a critical value.

Ticagrelor effectively and reversibly blocks murine platelet P2Y12-mediated thrombosis and demonstrates a requirement for sustained P2Y12 inhibition to prevent subsequent neointima.

OBJECTIVE: Our goal was to study the effects of ticagrelor on murine platelet function and thrombosis and characterize the time course of P2Y(12) inhibition required to inhibit neointima formation following vascular injury. METHODS AND RESULTS: Mice were treated with ticagrelor or vehicle. Platelet aggregation and P-selectin expression were assessed over time, and thrombus formation was assessed in laser-injured cremasteric arterioles of P2Y(12)+/+ and P2Y(12)-/- mice. Neointima formation in FeCl(3)-injured carotid artery was assessed in C57BL/6 mice treated with different regimens of ticagrelor. Ticagrelor inhibited platelet aggregation and P-selectin expression in a dose-dependent, reversible manner. Ticagrelor inhibited thrombus formation to the same extent as seen in P2Y(12)-/- mice. Neointima formation was markedly reduced in mice treated with ticagrelor before and 4 hours after injury (neointima area: control, 39 921±22 749 µm(2), versus ticagrelor, 3705±2600 µm(2); P<0.01), whereas administration of ticagrelor either before injury only or from 4 hours postinjury was ineffective. CONCLUSIONS: Ticagrelor effectively and reversibly inhibits P2Y(12)-mediated platelet function and thrombosis in mice. P2Y(12) inhibition is required both at the time of and after injury to effectively inhibit neointima formation. Additional studies are warranted to evaluate the role of P2Y(12) inhibition in preventing restenosis.

A comparative study of temporary splints: bonded polyethylene fiber reinforcement ribbon and stainless steel wire + composite resin splint in the treatment of chronic periodontitis.

UNLABELLED: The present clinical study was undertaken to determine the effects of splinting overunsplinted mobile teeth following periodontal surgery and compared the efficacy of two splinting materials, i.e. Ribbond ribbon + Composite with Stainless steel wire + Composite. MATERIALS AND METHODS: Total of 30 patients (20 experimental and 10 control) formed the study group. Entire study was extended over a period of 12 weeks for each patient and treatment plan was divided into 8 phases. Healing response was monitored and application, durability, biocompatibility of splint material was assessed. RESULTS: Splint had a promising and beneficial effects on anterior teeth exhibiting Grade I to Grade II degrees of mobility. Experimental group showed a greater reduction in tooth mobility compared to control group. There was no significant difference in plaque index and Ribbond Ribbon reinforced with composite resin was an excellent material for application, patient comfort, resistance to fracture, biocompatable and esthetic acceptability. CLINICAL SIGNIFICANCE: Splinting is recommended as an adjunct to periodontal surgery in the treatment of hypermobile teeth, especially in cases where patient discomfort is a prominent factor.

Benchmark solution for the stability of plane Couette flow with net throughflow.

This paper investigates the stability of an incompressible viscous fluid flow between relatively moving horizontal parallel plates in the presence of a uniform vertical throughflow. A linear stability analysis has been performed by employing the method of normal modes and the resulting stability equation is solved numerically using the Chebyshev collocation method. Contrary to the stability of plane Couette flow (PCF) to small disturbances for all values of the Reynolds number in the absence of vertical throughflow, it is found that PCF becomes unstable owing to the change in the sign of growth rate depending on the magnitude of throughflow. The critical Reynolds number triggering the instability is computed for different values of throughflow dependent Reynolds number and it is shown that throughflow instills both stabilizing and destabilizing effect on the base flow. It is seen that the direction of throughflow has no influence on the stability of fluid flow. A comparative study between plane Poiseuille flow and PCF has also been carried out and the similarities and differences are highlighted.