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The filament winding technique is the second popular process in basic composite manufacturing processes, which can provide an automated technique compared to traditional hand layup process. The continuous filament winding process is the manufacturing of glass reinforced polymer (GRP) pipes from continuously flowing glass fibre by winding it on an automatic machine. It is quick and reliable technology for making high performance parts. A big advantage of filament winding is that it uses continuous fibres which leads to very good material properties for both strength and stiffness. However, if there is any process abnormality it can cause defects such as voids, delamination, wrinkles, etc. which causes production loss or failure at customer loss leads to monetary and reputation loss. There was premature failure of GFRP composite pipes during hydrostatic (hydro) testing while laying out in the site were received. Two pipe samples, one referred as new or good pipe and another referred as leaked during hydro test, were investigated to find out the root cause of failure. The investigation consisted of field visits, studying the layout procedure, visual observation, microstructural characterization, thermogravimetric analysis (TGA) Fourier transform infrared spectroscopy (FTIR) and Raman analyses. Visual observations of the hydro test failed sample reveal some abnormal features like delamination of layers, circumferential cracks and white spots, while the leaked or used pipe shows features like air pockets, adherent foreign/ earthy materials, visible fibres and heterogeneity in colours. Adherence of earthy material on pipe's surface indicates that there is incomplete curing of polymer. Microstructural analysis exhibits that the volume fraction of fibres was very less (particularly in used pipe) in resin matrix and their distribution was also uneven. Raman, FTIR and TGA analysis suggest that impure or mixed resin material is used for production of pipe which failed during hydro test. Overall analysis suggests a defective manufacturing process and usage of expired polymer and sand along with non-prescribed fibre loading which might have initiated the failure of pipes during hydro test. [ABSTRACT FROM AUTHOR]

Divide shear assembly in a rebar rolling mill performs the function of cutting rebars into 72 m length. It uses two shear blades mounted on rotating arms, which rotate in directions opposite to each other and cut the rebars passing in between. These blades hit the rebars at a location from two opposite sides for cutting, and their cutting edges gradually become blunt after cutting of approximately 4000–5000 tons of rebars. Replacing the blunt blades results in interruption in operation leading to increased down time and resulting decreased productivity. A thorough metallurgical root cause analysis was carried out to improve the service life of shear blades. Damages on shear cutting blades were analyzed after trimming of 4000–5000T on thermo-mechanically treated rebars. Chemical analysis revealed that the material of the shear blade was AISI D2, which is a widely used material for cutting of rebars in cold conditions. AISI D2 is a high carbon grade with high Cr content. Microstructural examination revealed large fraction of coarse carbides in tempered martensitic matrix. However, excessive number of coarse carbides imparts brittleness which can limit its applications under severe conditions. The used blade exhibited chipping off materials at the cutting edge in brittle manner. The damaged blades and subsurface damage were examined using Profilometer, SEM, XRD and other metallography techniques. After detailed metallurgical investigation new material was developed to improve the (performance) of the cold shear blades. [ABSTRACT FROM AUTHOR]

The present paper attempts to quantify the amount of soil loss occurring in the Mayurakshi River basin of eastern India with the help of the empirical Revised Universal Soil Equation (RUSLE) Model. The areas of high erosion were identified and their spatial and temporal patterns and trends were monitored for the years 2008 and 2018. It was observed that the average soil loss increased by about 6% from 2008 to 2018. Among a variety of causal factors, the Shannon’s Entropy Index used in this study has identified the slope length and steepness factor (LS factor) as the most significant causal factor of erosion in the studied river basin. One of the novel approaches used in this study is the application of landscape ecological metrics in the domain of temporal erosion monitoring. An important conclusion drawn from the analysis is that the patches of high and moderate erosion are increasing significantly in terms of areal extent, whereas the extent of the patches of low erosion is decreasing with time. Therefore, appropriate management strategies prioritised on the high and moderate erosion patches are the need of the hour. [ABSTRACT FROM AUTHOR]

A laboratory plasma–wall interaction-based astrophysical gravito-electrostatic sheath (GES) model is methodologically applied to study the dynamic stability of the magnetoactive bi-fluidic solar plasma system in the presence of turbulence effect. The spherically symmetric GES-model formalism couples the solar interior plasma (SIP, internally self-gravitating, bounded) and the solar wind plasma (SWP, externally point-gravitating, unbounded) through the diffused solar surface boundary (SSB). A normal spherical mode ansatz results in a generalized linear quadratic dispersion relation depicting the modal fluctuations on both the SIP and SWP scales. A constructive numerical platform reveals the evolution of both dispersive and non-dispersive modal features of the modified-GES mode excitations. The reliability of the derived non-planar dispersion laws is concretized with the help of an exact analytic shape matching the previously reported results founded on the plane-wave approximation. It is found that the thermo-statistical GES stability depends mainly on the magnetic field, equilibrium plasma density and plasma temperature. It is speculated that the dispersive features are more pronounced in the self-gravitational domains against the electrostatic ones. The magneto-thermal interplay introduces decelerating (accelerating) and destabilizing (stabilizing) influences on the SIP (SWP), and so forth. At last, we briefly indicate the applicability of the proposed analysis to understand diverse helioseismic activities from the collective plasma dynamical viewpoint in accordance with the recent astronomical observational scenarios reported in the literature. [ABSTRACT FROM AUTHOR]

We propose an approach to find the optimal value of a convex semi-infinite program (SIP) that involves identifying a finite set of relevant constraints by solving a finite-dimensional global maximization problem. One of the major advantages of our approach is that it admits a plug-and-play module where any suitable global optimization algorithm can be employed to obtain the optimal value of the SIP. As an example, we propose a simulated annealing based algorithm which is useful especially when the constraint index set is high-dimensional. A proof of convergence of the algorithm is included, and the performance and accuracy of the algorithm itself are illustrated on several benchmark SIPs lifted from the literature. [ABSTRACT FROM AUTHOR]

This article focusses on power quality issues related with the operation of a wind energy conversion system employing a doubly fed induction generator (DFIG), integrated with a solar photovoltaic array, under unbalanced, and distorted grid conditions. The multiple-order DFIG electromagnetic torque ripples and grid active power ripples, resulting from the unbalanced and distorted grid, can be mitigated, however, at the cost of highly unbalanced and distorted currents. This article provides a possible solution towards a tradeoff by developing a flexible ripple minimization technique based on a cross-feedback extended second order generalized integrator for harmonics sequence separation (CextSOGI-HSS). The CextSOGI-HSS based current compensation enables a controlled minimization of ripple as per the customizable flexibility quotient. Furthermore, the current compensation technique employs an improved recursive least squares (IRLS) adaptive filtering algorithm for processing DFIG stator currents and local load currents. The IRLS algorithm improves grid currents harmonics spectra by filtering-out higher order harmonics from DFIG stator currents and nonlinear load currents, meanwhile, the effects of any load or stator currents unbalance on grid currents are also mitigated. Test results from a developed laboratory prototype confirm the efficacy of the presented flexible ripple minimization control technique. [ABSTRACT FROM AUTHOR]

This article presents a simplistic control approach and multimode operation of a wind-solar-based ac/dc microgrid. The islanded microgrid consists of a doubly-fed induction generator (DFIG) for wind energy conversion, and a solar photovoltaic array for solar energy conversion. In this configuration, the stator terminals of DFIG are connected at the point of common intersection (PCI) of ac loads via a stator-side solid-state transition switch (SSSTS). The developed control strategy is designed to seamlessly disconnect and reconnect the DFIG stator from the PCI based on the SSSTS operation, without interrupting power to ac and dc loads in the microgrid. The disconnection of stator terminals is required in the event of a prolonged period of no wind generation from the DFIG. The controller is synthesized to ensure no or low transient effect during the transition between the two operating modes, i.e., DFIG stator connected mode (SCM) and stator disconnected mode (SDM). Further, the power quality enhancement of stator voltages and currents amidst nonideal ac loads is ensured without need for computationally exhaustive approaches involving sequence decompositions, notch filters, resonant regulators, or load current sensors. Moreover, the power quality enhancement at the DFIG stator is achieved without injecting any undue harmonics in the DFIG rotor currents. The effectiveness of this islanded microgrid is verified through obtained results from a developed laboratory prototype. [ABSTRACT FROM AUTHOR]

Grid-interactive wind-solar distributed generation system (DGS) experiences substantial power quality (PQ) challenges pertaining to incessant voltage distortions in the utility grid and nonlinear loads at the point of common intersection. Such system non-idealities cause distortions in grid currents and infuse ripples in grid active and reactive powers. The effect of harmonically distorted voltages on DGS is further intensified in case of wind generation by means of a doubly-fed induction generator (DFIG), as its stator is directly coupled to the grid. Significant performance degradation with regard to distortions in DFIG currents, and ripples in stator power as well as DFIG torque, are observed. In this context, a control strategy, based on multiresonant higher order generalized integrator for harmonic estimation (MRHGI-HE) and a ϵ-normalized sign regressor least mean fourth (ϵ-NSRLMF) algorithm, for DGS employing solar photovoltaic array and DFIG-based wind generator, is presented in this article. Based on selected objective, the control approach puts-forth a feasible solution for alleviating the aforementioned PQ challenges. The MRHGI-HE provides improved harmonics estimation and superior disturbance rejection, than its conventional counterpart. Besides, ϵ-NSRLMF algorithm exhibits enhanced system dynamics, as compared with least mean fourth algorithm. The multiobjective control strategy is corroborated through extensive simulation and experimental studies, and results demonstrate the PQ improvements in the DGS. [ABSTRACT FROM AUTHOR]

• Loss of operators' ability to assess a situation typically precedes human errors that can lead to severe incidents and accidents at workplace. • We seek to develop proactive approaches to measure cognitive workload of the operators. • Operators' eye gaze behavior serves as a direct indicator of their cognitive processes, particularly evident during abnormal situations. • An information theory enabled eye metrics are proposed to quantify cognitive dynamics of operators. • A case study on EOT crane operations is conducted to validate the proposed eye metrics. Despite the deployment of sophisticated automation and control mechanisms in modern industries, accidents continue to occur. According to the literature, human error is the predominant contributor to these accidents. This depicts the deteriorating cognitive functions of human operators in managing abnormal situations. To proactively prevent human error, this study proposes information theory-enabled eye metrics to quantify the cognitive workload of the operator. The proposed metrics are based on gaze entropy and are evaluated using experimental studies. The results demonstrate that the proposed metrics reliably measure the cognitive dynamics of the operator during various abnormal situations. A case study on Electric Overhead Travelling (EOT) crane operations is presented to validate the superiority and effectiveness of the proposed measures. [ABSTRACT FROM AUTHOR]

Over the past few years, classic Machine Learning approaches such as Multinomial Naïve Bayes, Support Vector Machine as well as regularized Logistic Regression have been adapted to autocode injury narratives collected by the Bureau of Labour Statistics to reduce the manual effort needed to assign codes to these narratives. However, the effectiveness of these algorithms is yet to be explored on severe injury reports collected by the Occupational Safety and Health Administration (OSHA). This study aims to explore the performances of two Bayesian models for autocoding these reports, segregate narratives that require manual reviewing, and analyse the usefulness of presenting top k predictions for such reviews to human coders. The severe injury reports collected by OSHA from January 2015 to February 2021 were used in this study. Firstly, Unigram (UNB) and Bigram (BNB) Naïve Bayes models are used to classify the injury narratives, and their performance is analyzed. Furthermore, two filtering strategies are used a) Instances where the UNB and BNB models agree are autocoded b) Only cases where the two models agree and whose prediction probability is above a minimum threshold are autocoded. The remaining cases are filtered out to be reviewed and coded by manual coders. The sensitivity of top k predictions for the UNB, BNB, and UNB-BNB models are also compared and analyzed to aid human coders in assigning codes to the narratives that are filtered out. For fully autocoded data, the sensitivity of the UNB model is 75.21%, and that of the BNB model is 75.17%. The filtering approach has an overall sensitivity of 88.17%, flagging 31% of the injury narratives for manual review. The UNB model performs slightly better than the BNB model, and the accuracy increases as cases where the two models agree are considered and a prediction probability threshold is set. For the top 5 predictions, a maximum F1-score of 55% is achieved by the UNB-BNB model. [ABSTRACT FROM AUTHOR]

Unbalanced grid voltages, appearing at stator terminals of a doubly fed induction generator based wind energy conversion system, deteriorate its performance by instigating unwanted oscillations and distortions in output grid power and rotor currents, respectively, as well as by introducing unbalanced currents in the stator and the grid. This article aims to address these challenges using a coordinated control strategy based on an improved reduced order generalized integrator (IROGI) for positive and negative sequence estimation (PNSE). The IROGI–PNSE further enhances the control performance by eliminating the effects of dc component or unbalance in sensed voltages, on the grid synchronization. The coordinated control strategy uses hysteresis scheme for current control. The hysteresis-based current control requires fewer rotational transformations, and eliminates the need for PI/PIR regulators and notch filters for inner current control loops. This renders the control, computationally efficient. Moreover, the presented system is equipped to exhibit wind power leveling functionality through a battery energy storage. An approach, employing the region-specific wind speed frequency distribution graph, is utilized to constitute the power leveling operation modes. The effectiveness of the control scheme is demonstrated through test results on a prototype developed in the laboratory. [ABSTRACT FROM AUTHOR]

A series of novel pyrrole fused benzoxazinones/quinoxalinones has been evaluated for antiproliferative activity against breast cancer cell line, MCF7 and treatment‐resistant triple‐negative breast cancer cell line MDA‐MB‐231. Among which pyrroloquinoxalinones exhibited higher cytotoxicity. Furthermore, they showed insignificant cellular cytotoxicity in normal human cell HEK293T when treated with their respective IC50 concentrations. In silico molecular docking, study suggests that the inhibitory mechanism of pyrroloquinoxalinones probably mediated via modulation of breast cancer targets such as VEGFR2 and EGFR. The stability of target protein (VEGFR2 and EGFR)‐ligand (pyrroloquinoxalinones) interactions was validated by Molecular dynamic simulation (50 ns). Additionally, pyrrolobenzoxazinones/quinoxalinones were evaluated for in vitro antibacterial activity against Gram‐positive and Gram‐negative bacterial strains. All the compounds exhibited significant antibacterial activity (IC50 0.034–15.4 μM) towards the tested bacterial strains. These findings indicate that pyrrolobenzoxazinones/quinoxalinones are valuable scaffolds for the development of potent anticancer and antibacterial compounds. [ABSTRACT FROM AUTHOR]

Ultra-high-pressure (UHP) peridotites found along collisional zones record rare information from deep within the Earth. However, the estimation of depth of origin for these UHP rocks has been controversial. A major controversy remains related to the conjectural proposition of mantle transition zone (410–660 km) origin of the Alpe Arami (AA) garnet peridotite massif in the Swiss Alps. In this contribution, we show micro-textural evidence of precursor majoritic garnet by documenting exsolved rutile, high-Al orthopyroxene, jadeite-rich clinopyroxene and olivine within the AA garnets in this peridotite. We also document an unforeseen texture of olivine with 'necklace' like enstatite corona in the kelyphite formed after decomposition of relict garnet. These olivines bear FeTiO3 and Cr-spinel exsolution needles indicating retrogression from high-pressure Mg2SiO4. Thus, the occurrence of retrogressed high-pressure Mg2SiO4 with enstatite corona in kelyphite suggests majorite breakdown to precipitate high-pressure Mg2SiO4 near mantle transition zone (MTZ) depth. The SiO2 released during decompression of majoritic garnets reacts with the high-pressure Mg2SiO4 to produce the enstatite corona. Our documented micro-textures show high-pressure Mg2SiO4 are breakdown product of precursor majoritic garnet, indicating that these micro-textures of the AA peridotite massif are sourced from the mantle transition zone (MTZ). [ABSTRACT FROM AUTHOR]

Background:Post-natal depression, aserious mental health problem experienced by mothers 4 to 6 weeks after delivery. Patients suffering from post-natal depression are at higher risk of developing major depressive illness in future life. Objectives: To assess the prevalence of post-natal depression and its associates among women in a rural community in Hooghly district, West Bengal. Methodology: A crosssectional study was conducted among 83 post-natal mothers (period of 6th to 10th week after delivery) in a rural community in Hooghly district, West Bengal, selected by simple random sampling technique from the list of mothers attending the immunization clinic in a health centreduring the period of April 2019 to September 2019. Data was collected by face-to-face interview and review of records by house to house visits. Depression was assessed by Edinburgh post-natal depression scale (EPDS). Statistical analysis was done using Microsoft Excel and SPSS version 16. Results: Prevalence of post-natal depression among study participants came out to be 28.9%. Poor socio-economic status (p=0.000). Unplanned pregnancy (p=0.025), Pre-term delivery (p=0.011) and increase in number of parity (p=0.025) were found to be statistically significantly associated with post-natal depression. Conclusion: Post-natal depression is a major public health problem which should be dealt with great concern while making policy for betterment of maternal and child health especially in low income countries like India. This can be detected early by health care providers in primary health care set up using simple screening tools. Special care and counselling should be provided to them. [ABSTRACT FROM AUTHOR]

Spring steel is a name given to a wide range of steels used in the manufacture of springs, prominently in automotive and industrial suspension applications. High carbon of HC82BCr grade steel is drawn in the range of 4.0–3.0 mm as per customer's requirement for production of spring mainly in automobile components. This spring steel grade is produced from continuous cast billet of size 150 mm × 150 mm and then hot rolled into the size of 5.5 mm diameter wire rod. Quality aspects of these spring are significant as any inherent abnormality in the material could lead to unwanted productivity losses or quality claims or sometimes serious safety issues. In this present study, spring samples broken during coiling stage were collected from plants for understanding their quality aspect and potential causes of breakage during production. Detailed microstructural investigation revealed that the root cause of breakage of the spring is related to the segregation of phosphorous and chromium in the billet which leads to the formation of martensite (brittle and less ductile) in wire rod during rolling process. This volume change due to formation of martensite increases the stress level at the interface of pearlite and martensite. During wire drawing, this increased stress level causes formation of internal crack in subsequent passes causing breakage during spring formation. [ABSTRACT FROM AUTHOR]

Tetrazolo[1,5‐a]quinoline‐4‐carbaldehyde, 3‐oxo‐3‐phenylpropanenitrile, and β‐enamine were reacted in one‐pot to obtain highly functionalized quinolinyl‐1,4‐dihydropyridines. In addition to spectroscopic characterization, the structure of one of the compound is confirmed by single‐crystal X‐ray diffraction. Among all compounds evaluated for cytotoxic effect against MCF7, three quinolinyl‐1,4‐dihydropyridines (SKS13, 19, and 20) were found to be most active with half inhibition concentrations value of 7.87–9.55 μM. Molecular docking of the active molecules to various breast cancer targets revealed effective compounds have multiple receptor targeting potential in breast cancer. Our results corroborate quinolinyl‐1,4‐dihydropyridines as a valuable scaffold to develop anticancer drugs. [ABSTRACT FROM AUTHOR]

Thermal maturity is commonly assessed by various geochemical screening methods (e.g., pyrolysis and organic petrology). In this contribution, we attempt to establish an alternative approach to estimating thermal maturity with Raman spectroscopy, using 24 North American oil shale samples with thermal maturity data generated by vitrinite reflectance (VRo%) and pyrolysis (Tmax)-based maturity calculation (VRe%). The representative shale samples are from the Haynesville (East Texas), Woodford (West Texas), Eagle Ford and Pearsall (South Texas) Formations, as well as Gothic, Mancos, and Niobrara Formation shales (all from Colorado). The Raman spectra of disordered carbonaceous matter (D1 and G bands separation) of these samples were directly obtained from the rock chips without prior sample preparation. Using the Gaussian and Lorentzian distribution approach, thermal maturities from VR were correlated with carbon G and D1. We found that the Raman band separation (RBS) displayed a better correlation for equivalent VRe% than vitrinite reflectance VRo%. The RBS (D1–G) distance versus total organic carbon, free hydrocarbons from thermal extraction (S1), and the remaining hydrocarbon generating potential (S2) indicate that the RBS (D1–G) distance is also related to kerogen type. Data presented here from three methods of maturity determination of shale demonstrate that Raman spectroscopy is a quick and valid approach to thermal maturity assessment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Shotgun sequence and metabolomics in toddy , Indian fermented palm beverage were analysed. • Bacillota and Leuconostoc mesenteroides were the most abundant phylum and species. • Predictive metabolic pathways were annotated by KEGG/COG database. • Metabolomics analysis detected many primary and secondary metabolites. • Similarity and dissimilarity of toddy metagenome with other plant sap-based alcoholic beverages were analysed. Toddy is a popular fermented palm beverage of India. No scientific information on shotgun metagenomics and metabolomics are available on toddy of India till date. Hence, we choose the fermented date palm beverage, locally called khejur toddy, of West Bengal and Jharkhand states of India, to profile microbial community, their targeted and untargeted metabolites to study the putative bio-functional genes corresponding to regulatory metabolic pathways. Shotgun-based metataxonomic analyses revealed the existence of all domains where bacteria were the most abundant domain (94.48%) followed by eukaryotes (3.38%), viruses (1.53%) and archaea (0.61%). Overall, 54 phyla, 363 families, 1087 genera and 1885 species were observed and identified. Bacillota (49.3%) was the most abundant bacterial phylum. At species level, several species of bacteria and yeasts were detected in toddy samples which included Leuconostoc mesenteroides , Leuconostoc citreum, Lactobacillus helveticus, Lactiplantibacillus plantarum, Lactococcus lactis , Acetobacter malorum, Gluconobacter japonicus, Gluconacetobacter liquefaciens, Fructobacillus durionis , Zymomonas mobilis and yeasts Saccharomyces cerevisiae, Hanseniaspora uvarum and Hanseniaspora guilliermondii. Toddy metagenome was also compared with metagenome of pulque , the Mexican fermented fresh sap of Agave , which was retrieved from NCBI database, and also with metagenomic data of some amplicon-based previous studies on toddy and African fermented palm drink for similarity, dissimilarity and uniqueness among them. Predictive biosynthesis of ethanol, acetic acid, butanoate, linalool, staurosporine, prodigiosin, folic acid, riboflavin, etc. were annotated by KEGG/COG database. Clustered regularly interspaced short palindromic repeats (CRISPR) analysis detected 23 arrays (average length 23.69 bp ± 4.28). Comprehensive Antibiotic Resistance Database (CARD) analysis did not show the presence of any momentous antibiotic resistance gene among the major microbial members. Metabolomics analysis detected many primary and secondary metabolites. We believe this is the first report on complete shotgun metagenomics, and metabolomics of fermented palm drink of India as well as Eastern India. [ABSTRACT FROM AUTHOR]

Abstract Wire rods of Electrode Quality (EQ) steel, in sizes ranging between 5.5 mm and 12 mm, are normally produced from continuously cast billets by hot rolling in wire rod mill. These wire rods are subsequently drawn into wires with reduced section in wire drawing plants.The most common grade for EQ steels is ER70S-6 grade which is made of low carbon steel (0.06–0.08 Wt%) with high 'Mn' (1.40–1.50 Wt%) and low 'S' content (0.020 max Wt%). It is a premium mild steel wire formulated to high quality welds and trouble-free performance during applications involving heavy duty, high speed and spray transfer applications all the way to light duty, low speed and short-arc applications. Quality aspects of these drawn wires are of significance as any inherent abnormality in the material could lead to unwanted productivity losses or quality claims. In this present study, wire samples broken during manufacturing were collected from wire drawing plants for understanding their quality aspect and potential causes of breakage while drawing. Detailed microstructural investigation revealed that the root cause of breakage of the wires is related to the welding process deployed by the customer in joining the wire rods. The quality of weldment preparation needs to be paid attention because the two ends of the wires are not fused properly when subjected to welding. Highlights • The presence of bainite in the defect location indicates breakage took place from the welding location. • The hardness variation also indicates effect of welding in broken wire samples. [ABSTRACT FROM AUTHOR]

Traumatic coronary artery (CA) dissection is an extremely rare sequela of blunt chest trauma. Diagnosis of CA dissection in the setting of chest trauma is challenging. While conventionally coronary angiography has been the diagnostic tool of choice, modern imaging techniques such as optical coherence tomography can further improve diagnostic accuracy and help optimise treatment strategy. The ideal treatment modality for managing CA dissection has not been established with case reports revealing a range of treatment strategies ranging from CA bypass grafting to a completely conservative management. Here we present a case report of a 68‐year‐old man who suffered a traumatic proximal left anterior descending artery dissection as a consequence of a motor‐vehicle accident and was subsequently treated with a combination of conservative and interventional strategy with optimal patient outcome. [ABSTRACT FROM AUTHOR]

A washer is a thin plate with a hole that is normally used to distribute the load of a threaded fastener, such as a screw or nut. The washer used in automotive engine component is of split or spring lock washer. A ring split at one point and bent into helical shape. The benefit of spring lock washers lies in the trapezoidal shape of the washer. When compressed to loads near proof strength of the bolt, it will twist and flatten. This reduces the spring rate of the bolted joint which allows it to maintain more force under the same vibration levels. This prevents from loosening. The steel washer is one of the critical safety components for automobile engine, and its failure may cause severe safety issue. Before subjecting to manufacturing, the washer undergoes different process lines (wire rod → drawing → annealing → pickling → flattening → spring washer → single spring washer). After manufacturing of washer, toughness test is done to find out the metallurgical soundness and surface quality of the washer. In this toughness test the washer in a vice with the split ends free and straight above the vice jaws, a 90° segment of the free end is gripped with a wrench and bent. Washers should withstand twist test through a 90° angle without signs of fracture. The present paper highlights premature failure of automotive washer which failed during twist test. From the analysis, it has been observed that the distribution of spheroidized carbide is more uniform in good samples than that of rejected samples. Hardness profile variation was observed between good and bad spring samples. Overall investigation does not indicate any problem related to supplied wire rod material quality as no wire breakage problem observed. Inhomogeneous annealed structure in flat wire seems to result into variation in washer performance during twist test. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have significant uses in academic research and industrial process development. The tunable physicochemical properties like low vapor pressure, exceptional solvating properties, low inflammability etc. make them eco-friendly and green solvents. For industrial or laboratory purposes, it is very difficult to operate with high viscous ILs. Therefore, in this work, our attention is focused on modeling of viscosity of ILs using quantitative structure-property relationship (QSPR), in order to provide essential information to chemists enabling design of lower viscous ILs for addressing operational problems. In the present study, we have developed a QSPR model using a pool of 291 ILs using easily computable two-dimensional descriptors. Different strategies were applied to select appropriate variables for development of the final partial least squares (PLS) regression model. The model was validated extensively using different validation metrics to check the robustness and predictivity of the model for regulatory acceptance and enhancing confidence in QSPR predictions. The results showed that the model was statistically robust. Based on the insights obtained from the PLS model as mapped by the loading plot, scores plot, regression coefficient plot etc., we have concluded that intrinsic properties of cations, number of path count of order three at the anionic part, temperature, cation containing branched alkyl chain with large numbers of heteroatoms, shape of anions (spherical or rod), presence or absence of CH 2 RX fragment, presence or absence of quaternary nitrogen at the cationic part, aliphatic keto group at the anionic part, a C S bond at topological distance of 4 at the cationic part and presence or absence of a pyrrolidine ring at the cationic part of ILs play crucial roles to regulate the viscosity of ILs. [ABSTRACT FROM AUTHOR]

The upper and lower seal valves together form a key part in the top charging system of blast furnaces. The valves serve to create a gas-tight chamber during the charging of furnaces preventing the escape of blast furnace gas into the atmosphere during the operation. The axles in these valves are an integral part in the sealing mechanism of the valve flaps. Several accounts of failure of these axles in service at a Blast Furnace prompted the need for a predictive maintenance practice. This paper accounts for the failure analysis done on these axles to arrive at the root cause of failure and further the implementation of suitable NDT techniques for condition monitoring of the axles. This ultimately led to prevention of further in-service failures. [ABSTRACT FROM AUTHOR]

Torsion testing is used to determine the quality of steel wire used for motor tire beads in pneumatic tires. These steel wires must have good-tensile strength so that the tire bead can support the finished tire safely, and yet retain adequate ductility to deform easily around the forming wheel. The present paper highlights premature failure of bead wire which failed during torsion test. Torsion property is one of the important parameters of tire bead as it monitors both the metallurgical soundness and surface quality of a drawn wire. From the analysis, it has been concluded that probable reason for premature failure is due to strain aging (dynamic and static) caused by interstitial atoms which bounds the mobile dislocations resulting in increases yield strength and decreases bead formability. Moreover, the microstructural study indicates that failed specimen has misaligned and broken lamella of pearlite with globular cementite which creates the array of voids. These voids hinder the rotation of pearlite during torsion test thus leading to brittle fracture. [ABSTRACT FROM AUTHOR]

Zildat Ophiolitic Mélange (ZOM) of the Indus Suture Zone, Himalaya, represents tectonic blocks of the fragmented oceanic metasediments and ophiolite remnants. The ZOM is sandwiched between the Zildat fault adjacent to a gneissic dome known as Tso Morari Crystalline (TMC) and thin sliver of an ophiolite called as the Nidar Ophiolitic Complex. The ZOM contain chaotic low-density lithologies of metamorphosed oceanic sediments and hydrated mantle rocks, in which carbonates are present as mega-clasts ranging from 100 meters to few centimeters in size. In this work, calcite microstructures, fluid inclusion petrography and stable isotope analyses of carbonates were carried out to envisage the emplacement history of the ZOM. Calcite microstructure varies with decreasing temperature and increasing intensity of deformation. Intense shearing is seen at the marginal part of the mélange near Zildat fault. These observations are consistent with the mélange as a tectonically dismembered block, formed at a plate boundary in convergent setup. The δO and δC isotope values of carbonates show bimodal nature from deeper (interior) to the shallower (marginal, near the Zildat fault) part of the mélange. Carbonate blocks from deeper part of the mélange reflect marine isotopic signature with limited fluid-rock interaction, which later on provide a mixing zone of oceanic metasediments and/or hydrated ultramafic rocks. Carbonates at shallower depths of the mélange show dominance of syn-deformation hydrous fluids, and this has later been modified by metamorphism of the adjacent TMC gneisses. Above observations reveal that the mélange was emplaced over the subducting Indian plate and later on synchronously deformed with the TMC gneissic dome. [ABSTRACT FROM AUTHOR]

Reinforcing bars, popularly termed 'rebars,' are used to impart tensile strength to concrete structures. Concrete has high resistance to weathering and fire and high compressive strength but almost no tensile strength, hence rebars are used to provide the latter to concrete. Property consistency along the length of rebars is an important prerequisite. When the finished product is subjected to thermomechanical treatment (TMT), proper control of rolling and water box parameters and efficient pinch rolling are needed to achieve acceptable properties. Variation of yield strength (YS) along TMT bars from the front to back end has been observed within the same heat treatment. In the presented investigation, it was observed that pinch rolling ineffectiveness is the main reason for the poor mechanical properties at the back end. The pinch roller was unable to support the back end of the TMT bars properly to maintain the speed and tension of the bars, resulting in nonuniform cooling of the back end through the water box and subsequent mechanical property failure. Due to the substandard material of the pinch roller, it was unable to hold the back end of the bar properly. Based on analysis of the roller it was concluded that it failed due to improper microstructure, resulting in inadequate hardness and toughness for the stringent operating conditions. AISI H13 is a better material to use in such high-service-temperature conditions. Moreover, proper heat treatment is needed to achieve adequate hardness and microstructure properties. After proper heat treatment of pinch rollers, their service life was increased twofold, minimizing the YS variation along the rebars. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbial community of cheonggukjang , Korean fermented soybean food was analysed by shotgun sequence. • Domains showed bacteria (95.83%), and rest were virus, eukaryotes and archaea. • Firmicutes (98.04%) was the most abundant phylum with Bacillus thermoamylovorans (39.69%) as the abundant species. • Different genes and the corresponding functional pathways were predicted computationally. • Predictive amino acids from KEGG annotation was validated with experimental amino acid profiles. Cheonggukjang is a naturally fermented soybean food of Korea. The present study was aimed to reveal the whole microbial community structure of naturally fermented cheonggukjang along with the prediction of microbial functional profiles by shotgun metagenomic sequence analysis. Metataxonomic profile of cheonggukjang samples showed different domains viz. bacteria (95.83%), virus (2.26%), unclassified (1.84%), eukaryotes (0.05%) and archaea (0.005%). Overall, 44 phyla, 286 families, 722 genera and 1437 species were identified. Firmicutes was the most abundant phylum (98.04%) followed by Proteobacteria (1.49%), Deinococcus-Thermus (0.14%). Bacillus thermoamylovorans was the most abundant species in cheonggukjang followed by Bacillus licheniformis , Bacillus glycinifermentans , Bacillus subtilis , Bacillus paralicheniformis , Bacillus amyloliquifaciens , Brevibacillus borstelensis , Brevibacillus sonorensis Brevibacillus, Acinetobacter , Carnobacterium, Paenibacillus, Cronobacter Enterococcus , Enterobacter, Terriglobus, Psychrobacter and Virgibacillus. A colossal diversity of the genus Bacillus was detected with 150 species. Functional analysis of cheonggukjang metagenome revealed the genes for the synthesis and metabolism of wide range of bioactive compounds including, various essential amino acids, conjugated amino acids, different vitamins, flavonoids, and enzymes. Amino acid profiles obtained from KEGG annotation in cheonggukjang were validated with experimental result of amino acid profiles. [ABSTRACT FROM AUTHOR]

The SE Ladakh (India) area displays one of the best ‐preserved ophiolite sections in this planet, in places up to 10 km thick, along the southern bank of the Indus River. Recently, in situ ultra‐high pressure (UHP) microstructural evidences from mantle transition zone (MTZ ∼ 410–660 km) with diamond and reduced fluids were discovered from two peridotite bodies in the basal mantle part of this Indus ophiolite (Das et al., 2015; 2017). Ultrahigh‐pressure phases were also found by early workers from podiform chromitites of another equivalent Neo–Tethyan ophiolite in southern Tibet (e.g., Yang et al., 2007; Yamamoto et al., 2009). However, the MTZ phases in the Indus ophiolite are found in silicate peridotites not metallic chromitites and the peridotitic UHP phases show systematic and contiguous phase transitions from the MTZ to shallower depth, unlike the discrete ultrahigh‐pressure inclusions, all in Tibetan chromitites. The gradual change in oxygen fugacity (fo2) and fluid composition from (C‐H + H2) to (CO2 + H2O) in the upwelling peridotitic mantle causing melting to produce MORB. At shallow depths (< 100 km) the free water stabilizes into hydrous phases, such as amphiboles and serpentines, capable of storing water and prevent melting (Fig. 1). The results from Indus ophiolite provide unique insights into deep sub‐oceanic mantle processes, and link deep mantle upwelling and MORB genesis (Fig. 1). The tectonic setting of Neo‐Tethyan ophiolites has been a difficult problem since the birth of plate tectonics concept. This problem for the origin of ophiolites in mid‐ocean ridge versus supra subduction‐zone settings clearly confused the Geoscience community. However, Indian Ocean –type isotopic characteristics are present in Neo‐Tethyan ophiolites (Zhang et al., 2005). Recently, continental materials (quartz, k‐feldspar etc.) bearing old zircons (up to 2700 Ma) are also recovered from UHP chromitite of Tibetan ophiolite (Yamamoto et al., 2013). Eventually, the presence of older continental material can produce non‐MORB like basalts in Neo‐Tethyan ophiolites in mid‐oceanic‐ridge following the "historical contingency" model (Moores et al., 2000). [ABSTRACT FROM AUTHOR]

The SE Ladakh (India) area displays one of the best ‐preserved ophiolite sections in this planet, in places up to 10 km thick, along the southern bank of the Indus River. Recently, in situ ultra‐high pressure (UHP) microstructural evidences from mantle transition zone (MTZ ∼ 410–660 km) with diamond and reduced fluids were discovered from two peridotite bodies in the basal mantle part of this Indus ophiolite (Das et al., 2015; 2017). Ultrahigh‐pressure phases were also found by early workers from podiform chromitites of another equivalent Neo–Tethyan ophiolite in southern Tibet (e.g., Yang et al., 2007; Yamamoto et al., 2009). However, the MTZ phases in the Indus ophiolite are found in silicate peridotites not metallic chromitites and the peridotitic UHP phases show systematic and contiguous phase transitions from the MTZ to shallower depth, unlike the discrete ultrahigh‐pressure inclusions, all in Tibetan chromitites. The gradual change in oxygen fugacity (fo2) and fluid composition from (C‐H + H2) to (CO2 + H2O) in the upwelling peridotitic mantle causing melting to produce MORB. At shallow depths (< 100 km) the free water stabilizes into hydrous phases, such as amphiboles and serpentines, capable of storing water and prevent melting (Fig. 1). The results from Indus ophiolite provide unique insights into deep sub‐oceanic mantle processes, and link deep mantle upwelling and MORB genesis (Fig. 1). The tectonic setting of Neo‐Tethyan ophiolites has been a difficult problem since the birth of plate tectonics concept. This problem for the origin of ophiolites in mid‐ocean ridge versus supra subduction‐zone settings clearly confused the Geoscience community. However, Indian Ocean –type isotopic characteristics are present in Neo‐Tethyan ophiolites (Zhang et al., 2005). Recently, continental materials (quartz, k‐feldspar etc.) bearing old zircons (up to 2700 Ma) are also recovered from UHP chromitite of Tibetan ophiolite (Yamamoto et al., 2013). Eventually, the presence of older continental material can produce non‐MORB like basalts in Neo‐Tethyan ophiolites in mid‐oceanic‐ridge following the "historical contingency" model (Moores et al., 2000). [ABSTRACT FROM AUTHOR]

Three simple, precise and accurate spectrophotometric methods have been developed for the estimation of bosentan in pharmaceutical formulations. Bosentan exhibits maximum absorbance at 272.0 nm (Method A). In Method B (D1) is a first derivative method showing minima at 284.65 nm and Method C is an Area under Curve (AUC) method (260.0-280.0 nm). The drug obeys the Beer-Lambertís law in the concentration range of 0.5-100 μg/ml in all the three methods. The methods were validated and can be successfully applied to estimate bosentan in pharmaceutical dosage forms. [ABSTRACT FROM AUTHOR]

Role of different precursors on the nanostructure of hydrothermally synthesised ZnO is studied here. Well defined pencil like nanorods obtained from zinc acetate precursor are found to exhibit the highest photoluminescence intensity. Photoluminescence spectra as well as Commission Internationale de l'Eclairage (CIE) plots of all the samples show blue emission. To get an idea of the applicability of ZnO nanorods as the emissive layer in light emitting diodes, external electroluminescence efficiency (ELE) is determined using a mathematical model. ELE of pencil like nanorods reveals 1.2% external electroluminescence quantum efficiency at turn-on voltage of 2.6 V. The Forster resonance energy transfer (FRET) among ZnO (donor) and methylene blue (acceptor) can play a vital role on the photocatalytic activity of ZnO. In our case due to less overlap between absorption spectrum of methylene blue and emission spectrum of all the ZnO samples, FRET cannot occur between ZnO and methylene blue (MB) for a longer distance of separation between them. Hence ZnO synthesised from zinc chloride having lower particle size leads to less separation between ZnO and MB molecules compared to other two ZnO samples and shows the highest photocatalytic activity. • The nanostructures of ZnO depend upon precursor used in hydrothermal process. • The PL intensity varies with variation of nanostructure. • The electroluminescence efficiency of ZnO rods is 1.2% at 2.6 V. • FRET from ZnO to dye affect its photocatalytic property. [ABSTRACT FROM AUTHOR]

• The fermentation characteristics of toddy were studied. • Co-existence of bacteria and fungi during natural fermentation of toddy. • Leuconostoc and Hanseniaspora were abundant in the early stages of fermentation. • Lactobacillus, Gluconoacetobacter and Saccharomyces were abundant in later stages. • Functional profiles such as metabolites, vitamin and amino acids were predicted. Toddy is a traditional mild-alcoholic drink of India, which is produced from fresh palm saps by natural fermentation. We studied the successional changes in bacterial and fungal communities during the natural fermentation (0 h–96 h) of toddy. During fermentation, alcohol content of the fermenting saps increased significantly from 0.6 %±0.15 to 5.6 %±0.02, pH decreased from 6.33 %±0.02–3.93 ± 0.01, volatile and titratable acidity acidity (g/100 mL) increased from 0.17 ± 0.02 (0 h) to 0.48 ± 0.02 (96 h) and 1.30 ± 0.005 (0 h) to 2.47 ± 0.005 (96 h), respectively. Total sugar content and ˚BRIX also decreased during the fermentation. Firmicutes (78.25 %) was the most abundant phylum followed by Proteobacteria (21.57 %). Leuconostoc was the most abundant genus in the early stages of fermentation. However, Lactobacillus and Gluconoacetobacter were found abundant with increase in pH during the later phases of fermentation (72 h–96 h). Ascomycota (99.02 %) was the most abundant fungal phylum. Hanseniaspora was the abundant yeast in the initial stages of fermentation, whereas the population of Saccharomyces increased significantly after 24 h of fermentation. Torulaspora , Lachancea and Starmerella showed their heterogeneous distribution throughout the fermentation. Computational analysis of metagenomes based on KEGG and MetaCyc databases showed different predictive functional profiles such as folate biosynthesis, glutathione metabolism, terpenoids biosynthesis and biosynthesis of amino acids with significant differences between the fresh palm saps and fermenting saps during toddy fermentation. [ABSTRACT FROM AUTHOR]

This article presents the performance evaluation of the solar photovoltaic small hydro battery based energy storage (BES) system having automatic mode switching capability. A BES allows the microgrid to operate in constant power mode depending upon the maximum power of a battery. Moreover, a block sparse proportionate least mean M-estimate algorithm is utilized for the system to operate in the variable power mode of the utility grid. A dc offset rejection loop is included to eliminate the offset from the load currents. A synchronization unit is employed that signals the static transfer switch to transfer between utility-interactive mode (UIM) and standalone mode (SM). The estimation of frequency is required for the system to synchronize with the utility grid, which is accomplished using a frequency adaptive filter. A comprehensive description of the system, in various operating modes, is given, i.e., SM, UIM, transition from SM to UIM, and transition from UIM to SM. Besides, the microgrid is validated with a hardware prototype and the synchronization is achieved by complying with the standards of voltage, phase angle difference, and frequency as mentioned in the IEEE 1547-2018 standard. The power quality index of the grid and hydro generator attributes in the utility mode and under load unbalance in the SM is provided, which complies with the IEEE 519 standard. Comparative performance is provided to depict the robustness of the control algorithm. [ABSTRACT FROM AUTHOR]

To provide clean and cheap electricity in remote and hilly areas, where the availability of the utility grid is of concern, small hydro generation possesses a promising solution. This article focuses on the utilization of a small hydro energy conversion (SHEC) system. An enhanced Lyapunov's demodulator (ELD)-based orthogonal signal generator technique is utilized for the extraction of active and reactive components of the load currents in the standalone mode. Moreover, synchronization of the SHEC system is required with the utility grid for smooth power transfer, henceforth the ELD scheme is used for the estimation of frequency whose range complies with the IEEE 1547-2018 std. The system is investigated for both standalone as well as seamless transfer to grid-connected operation and serves the major concerns, i.e., in the standalone mode, it regulates the frequency and terminal voltage to their nominal values at the point of interconnection (PoI). Besides, it mitigates the harmonics injected into the system on account of nonlinear load, which distorts the voltages and currents at the PoI in both modes. Finally, it rectifies the unbalance in the voltages and currents of the hydrogenerator due to the presence of unbalanced loads at the PoI. A comparative analysis of the ELD scheme with other algorithms is provided, which depicts the robustness of the control algorithm. Moreover, comparative performance of estimation of frequency extracted from the ELD approach with other control is also given. A hardware prototype is developed and test results are presented to validate the above-mentioned features. The power quality results depict the total harmonic distortion of the voltages and currents to comply with the IEEE-519 std. [ABSTRACT FROM AUTHOR]

• The work focused on breakage of wires during drawing. • It contains low carbon steel with high Mn and Si. • It is a premium electrode grade to produce high quality welds and trouble-free performance during welding process. • In the present work, microstructural and different thermo-mechanical study of failed wire and wire rod sample was conducted to determine the origin of failure. • Wire breakage took place due to presence of hard brown phase due to incomplete transformation during retarded cooling process at hot rolling operations. The research work provides an intensive analysis of premature failure of the wires during cold drawing operations. The steel wires are made of WR3M grade, which contains low carbon (0.06–0.08 wt%) with high 'Mn' (1.40–1.50 wt%) and 'Si' (0.80–1.00 wt%). It is a premium low carbon electrode grade, which can produce superior quality welds and trouble-free performance during different continuous welding process. This welding grade is manufactured from continuous cast billet of dimension 150 mm × 150 mm and then hot rolled through successive rolls to achieve desired dimension. Present work includes microstructural and different thermo-mechanical study to determine the origin of premature failures of wires. Investigation suggested that wire breakage took place due to the presence of light brown hard phase (martensite) which makes the material brittle and initiate chevron cracks during drawing operations. X-ray mapping doesn't provide any segregation along or near the light brown hard phase. From different plant trials and thermo-mechanical study, it reveals that the light brown hard phase formed due to incomplete transformation of wire rods during retarded cooling process at hot rolling stage. [ABSTRACT FROM AUTHOR]

• HFRC is the simple combination of two different types of fibres in concrete. • The optimum increase in strength of HFRC was achieved at 2% hybrid fibre content. • A strong relation was found between hybrid fibre content and mechanical properties. • Experimental and predicted strengths of HFRC showed reasonably good agreement. Hybrid fibre reinforced concrete (HFRC) is one of the most promising construction techniques and repairing material in recent times for the construction industry. Generally, plain concrete has a very low tensile strength and limited resistance to cracking prior to the ultimate load. Fibre hybridization with different types of fibres helps in resisting these cracks in the concrete structures. This research aims to study the rheological and mechanical properties of HFRC made with steel and coconut (coir) fibre in comparison to control concrete. For this purpose, the experimentation was carried out in the laboratory on cylinders and prisms specimens made from conventional (control) concrete and HFRC with 2%, 4%, and 6% of fibre concentration by weight of cement. Besides, the concentration of waste steel fibre was kept at a constant rate of 1% for all of the HFRC mix in this study. The rheological properties of HFRC mixes were obtained by slump test, compacting factor test, ball penetration test, and density test. These properties were then compared to the corresponding properties of control concrete. On the other hand, compressive strength test, splitting tensile test and flexural tests were performed to attain the mechanical properties of HFRC. The test results indicate that the incorporation of hybrid fibres in the concrete decreases the concrete workability compared to the control concrete. The experimental results showed that the compressive strength is improved compared to the control mix whether the splitting and flexural strength shows an 18.36% and 24.87% improvement over the control mix. Finally, the inclusion of optimum content of hybrid fibres that is 2% by weight of cement showed enhancement in the mechanical properties of HFRC in terms of compressive, tensile and flexural strength with compared to control concrete. [ABSTRACT FROM AUTHOR]

Ophicarbonates are found in ophiolite-associated peridotites and bear signature of fluid-rock interaction either on ocean floor or during ophiolite emplacement. The occurrence of ophicarbonate veins hosted by ultramafic rocks of the Indus Ophiolite, Nidar Valley, Ladakh Himalaya, is interpreted within the context of serpentinization of the allochthonous Cretaceous upper mantle section during uplift of the Himalaya orogen. Mixed dolomite-calcite obtained from two veins show carbon isotope ratios consistent with an origin from bicarbonate-dominated fluid and inconsistent with incorporation of atmospheric carbon dioxide in subaerial contact with high pH waters of serpentinization. Strontium isotope ratio of 0.711452–0.712041 are consistent with serpentinization subsequently to emplacement of the ophiolite and by interaction with Cretaceous seawater mixed with continental crust-derived fluid during Neo-Tethys closure. The predominance of lizardite and chrysotile in ophicarbonate veins as documented by Raman spectra also supports a low temperature serpentinization during ophiolite emplacement. The presence of hydrocarbon peaks in fluid inclusions in serpentinized olivine suggests that some of the dissolved inorganic carbon reacted with hydrogen released through oxidation of iron. The ophicarbonates and serpentines in peridotite of Indus ophiolite bear signature of a paleo-environment for Fischer-Tropsch reactions during the last phase of Neo-Tethys closure. • Petrology and geochemistry of the ophicarbonates hosted in Indus ophiolite. • Ophicarbonates retain signature of continental crust-derived fluids and seawater. • Serpentinization triggered hydrocarbon formation by Fischer-Tropsch reaction. • The ophicarbonate veins formed during Neo-Tethys closure. [ABSTRACT FROM AUTHOR]

Abstract: The Compact Muon Solenoid (CMS) experiment at the LHC incorporates a 66 million channel silicon pixel detector at its center for track seeding and precise vertexing. The hardware and data acquisition software of the pixel detector are briefly introduced in this paper. Experience with installation is succinctly recounted and some of the calibrations performed during the commissioning period are described. Preliminary performance numbers like charge collection and hit residuals from cosmic ray tracks are presented. [ABSTRACT FROM AUTHOR]

Introduction: Upper Gastrointestinal Endoscopy is considered the best screening tool for varices among patients with chronic liver disease. However, it is an expensive and invasive procedure that is not routinely available in rural India. Abdominal ultrasonography along with colour Doppler study is an inexpensive test commonly ordered for patients with chronic liver disease. Recent literature suggests that ultrasonographic parameters can be used to predict varices. Aim: To determine if ultrasonography of the entire abdomen and spleno-portal Doppler study findings can predict oesophageal varices in patients with chronic liver disease. Materials and Methods: The present hospital-based observational, cross-sectional study was conducted in the indoor ward of the Department of General Medicine at Medical College and Hospital, Kolkata, India, over a duration of one year from February 2021 to February 2022. Total 100 patients with chronic liver disease, admitted to the hospital ward, were included in the study. Child-Turcotte-Pugh (CTP) scores were obtained for all patients. Ultrasonographic and spleno-portal Doppler indices, such as liver size, spleen size, portal vein diameter, splenic vein diameter, peak systolic velocity of the portal vein, and portal vein/splenic vein diameter ratio, were measured alongside upper gastrointestinal endoscopy to detect varices. The data were analysed using Statistical Package for Social Sciences (SPSS) version 28.0. The Chi-square test was used to test for significant differences in proportions (categorical data), and the independent t-test and Analysis of Variance (ANOVA) with Tukey's Post-hoc test were employed to test for significant differences in means (continuous data). Additionally, Receiver Operating Characteristic (ROC) curves were obtained for statistically significant parameters to predict the presence of varices. Results: The study enrolled 100 patients (63% males, 37% females) with a mean age of 49.19±14.965 years, ranging from 14 to 91 years. (median age of 52, range 14-91 years). Of these, 68 patients (68%) had oesophageal varices, while 32 (32%) did not. The study found that a mean spleen size of 13.55 cm, a mean portal vein diameter of 12.5 mm, and a mean splenic vein diameter of ≥9.05 mm were predictive of varices. Additionally, a mean portal vein/splenic vein diameter ratio of 1.6150 was also predictive of varices. However, there was no significant difference in mean liver size and peak systolic velocity between those with and without varices. Conclusion: The present study suggests that a spleen size, portal vein diameter, splenic vein diameter, and portal vein/splenic vein diameter ratio can be reliably used to predict oesophageal varices among patients with chronic liver disease. [ABSTRACT FROM AUTHOR]

Background: Scrub typhus is a zoonotic infectious disease caused by the Gram-negative coccobacillus Orientia tsutsugamushi. Meningoencephalitis occurs in two-thirds of all the infected cases. Aims and Objectives: The study of these cases was conducted to study the clinical, biochemical, and hematological features of scrub typhus meningoencephalitis. Materials and Methods: We included 12 patients who were admitted in the General Medicine Ward of Medical College and Hospital, Kolkata, between May 2021 and July 2022. The serum scrub typhus immunoglobulin M (IgM) test was used to diagnose the cases after ruling out dengue, malaria, leptospirosis, bacterial, tubercular, and viral meningoencephalitis. Results: A triad of fever, altered sensorium, and meningeal signs were present in all of the cases. 2 patients had seizures, 1 patient had lateral rectus palsy, 1 patient had a generalized maculopapular rash, and eschar was seen in only 2 cases. The most common laboratory abnormalities were hyponatremia, anemia, and transaminitis (each 83.33%). 8 cases (66.7%) had a combination of anemia, hyponatremia, and transaminitis. Cerebrospinal fluid abnormalities included protein elevation (75%) and lymphocytic pleocytosis (83.33%). Scrub typhus IgM was positive in all of them. All the cases showed excellent response to doxycycline. Conclusion: A high degree of clinical suspicion is required to diagnose scrub typhus meningoencephalitis. The eschar is detected in very few cases and it may be difficult to recognize the same among the dark-skinned Indian population. However, as per our study, any case of meningoencephalitis with a combination of anemia, hyponatremia, and deranged liver function tests should always raise the possibility of the aforementioned disease and doxycycline therapy must be started promptly. [ABSTRACT FROM AUTHOR]

The article describes the case of a 13-year-old boy with fever, loose stools, vomiting, redness of eyes and a generalized maculopapular rash for a week and developed peeling of skin over palms and soles. Topics discussed include findings on his systemic examination, his diagnosis of Kawasaki disease, and the separation of his nails which suggested onchomadesis.

Background: Snake bite is one of the most neglected diseases in South East Asian region. Common Krait (CK) (Bungarus caeruleus) is the deadliest snake found in the dry zones of India. With the polyvalent anti-venom serum (AVS) remaining the cornerstone of treatment of neurotoxic snake envenomation, there is no universally accepted treatment for CK envenomationassociated neuroparalysis, except supportive measures. Aims and Objectives: Our study was conducted to describe the epidemiology, define clinical features, study outcome, and apparent efficacy of calcium gluconate in preventing or reversing neuromuscular paralysis with respiratory failure in CK bite patients. Materials and Methods: This study is a prospective observational study done on 52 CK bite patients. Patients were enrolled according to inclusion and exclusion criteria and were treated with AVS and calcium gluconate infusion according to National Standard Guideline, 2016. Patients developing severe respiratory muscle paralysis were offered mechanical ventilation. Results: Patients developed ptosis and dysphagia, pain abdomen, cyanosis, paralysis of jaw and tongue, perioral numbness, altered sensorium, dysphonia, ophthalmoplegia, and paradoxical breathing. 21.15% of patients developed respiratory failure and needed ventilator support with average critical care unit stay of 3 days and average stay on a ventilator of 2 days. 3 patients expired (case fatality rate 5.77%). The average hospital stay was 3.33 days. Conclusion: Our study shows that early intervention in patients of CK bite with neurotoxic envenomation, with calcium gluconate infusion, leads to less mortality and morbidity compared to other relevant studies. Further large-scale studies are required for better understanding and implementation. [ABSTRACT FROM AUTHOR]

Summary: In this study, an optimal double frequency second order generalized integrator (DFSOGI) based grid side converter control (GSC) is used for monitoring active power injection from the DFIG wind energy system as well as improving power quality at utility grid terminals. The reference DC voltage is adapted to variations in voltage at the point of common coupling (PCC) that reduces the burden on the converter switches and switching losses. In addition, an intelligent control technique based on white shark optimization algorithm (WSO) is endorsed, where an objective problem is formulated to obtain the desired parameters of the controller. Finally, time‐domain simulations are conducted in MATLAB environment that demonstrate the validity of the implemented control over various operating conditions. To affirm the adequacy of the proposed control strategy, the response of DC link voltage obtained through optimal tuning is compared to the conventional one. The proposed WSO tuning outperforms traditional manual tuning pertaining to enhancing the overall performance of the DFIG system. The designed WSO gains exhibit better steady‐state and transient performance including settling time, steady‐state error, and peak of over amplitude and harmonic distortion. The grid currents' total harmonic distortion (THD) is within 5% that meets specified IEEE‐519 standard. [ABSTRACT FROM AUTHOR]

We present a first report for developing stimulus responsive hydrogels via free radical aqueous polymerization technique using Acrylic acid (AAc), methacrylic acid (MAAc) and diethylaminoethyl methacrylate (DEAEMA). The morphological aspects of poly(AAc-co-DEAEMA) (pAcD) and poly(MAAc-co-DEAEMA) (pMcD) were investigated to delineate the relevant mechanism of hydrogel formation for better understanding of their mechanical behaviour. The formulated hydrogels were found to have a structural framework comprising inter-connected nanogels and continuous outer skin with macroporous interiors. An abrupt increase in the peak intensities specific to the polymer and a simultaneous decrease in the water related peaks in the attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra exhibited the phenomenon of phase separation, whereas peaks of proton nuclear magnetic resonance (HNMR) revealed hydrogen bonding and electrolytic complexation between the monomers. Biocompatibility is the hallmark for any drug carrier and was evaluated by both in vitro and in vivo testing. Administration of the prepared hydrogels to rat models did not cause any significant affect on the vital organs. [ABSTRACT FROM AUTHOR]