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This paper presents a groundbreaking advancement in terahertz (THz) technology through the introduction of a novel ultrathin absorber. Composed of vanadium dioxide (VO2) and graphene, this absorber offers a non-metallic solution for wideband absorption, covering an impressive frequency range from 1.198 THz to 8.752 THz (7.554 THz). Our absorber exhibits exceptional tunable and switchable performance, a significant achievement considering the challenge of achieving frequency tunability across broadband absorption ranges, which was the primary focus of our research endeavor. Furthermore, our proposed absorber demonstrates remarkable characteristics, achieving up to 80% absorption even at high incidence angles of up to 80°. Additionally, the absorber enhances Shielding Effectiveness in electromagnetic interference (EMI) shields and stealth systems, further highlighting its versatility and potential impact in various applications.

The main flavonoid pigment in the petals of Kigelia Africana and the calyx of Hibiscus sabdariffa is anthocyanin, responsible for the vibrant red, maroon, and purple hues in flowers. This pigment can modulate incident light on flowers, prompting its selection for detailed investigation. TiO2 nanostructures were synthesized using a one-step hydrothermal method, revealing the formation of nanorods and a single-phase rutile structure through FESEM and XRD analyses, respectively. The study aimed to assess the impact of various solvents on the extraction of natural dyes, which were subsequently sensitized on TiO2 photoanodes for DSSC applications. Four solvents-water, water with HCl, ethanol, and citric acid were employed to extract natural dyes from Kigelia Africana's petals and Hibiscus sabdariffa's calyx. Notably, dyes extracted with citric acid demonstrated promising results. The conversion efficiency of DSSCs fabricated with Kigelia Africana dye and Hibiscus sabdariffa dye, extracted using citric acid as the solvent, was found to be 0.87 % and 0.92 %, respectively. The implications of these findings are discussed.

Silicon photonics is a rapidly developing field that offers cost-effective biosensors with improved sensitivity and the potential for interconnecting with other electronic devices for instant disease diagnosis. The Mach Zehnder interferometer architecture (MZI) is a key technology for biosensors, as it detects changes in refractive index (RI) caused by the presence of biomolecules. In this study, a silicon-polymer double-slot waveguide-based MZI was designed, with a small mode area and a large evanescent field to enhance light-analyte interaction. The waveguide was optimized by converting a normal slot waveguide into a double-slot waveguide with varying slot widths. In transmission spectrum, the wavelength shift was measured for both normal and disease samples. Additionally, the loss at a specific wavelength was analyzed to understand the impact of the biomolecule on the sensor performance. The results show that this sensor has a high sensitivity of 2.39 X10^5 nm/RIU, making it a promising candidate for biosensing applications.

In this research, we introduce a metamaterial biosensor designed for the detection of various viruses. The proposed sensor configuration comprises four square split ring resonators (SRR) coupled with a central graphene ring. The strong coupling between SRR and graphene ring results in near-perfect absorption at a frequency of 1.354 THz. To enhance versatility, the sensor’s performance can be tuned and controlled by adjusting the chemical potential ( $\mu _{\mathrm {c}}$ ) of the graphene. Additionally, we validate the sensor’s functionality through an equivalent circuit model. Moreover, the proposed sensor demonstrates outstanding performance metrics, including a high sensitivity (S) of 1.7 THz/RIU, a Figure of Merit (FOM) of 165.09 RIU−1, high-quality factor (Q) of 112.5. Despite its reduced structural thickness of $3~\mu \text{m}$ , it remains suitable for integration into nanotechnology devices. Furthermore, the absorber exhibits exceptional absorption properties even at steep incidence angles, expanding its applicability in diverse scenarios. Its potential to detect a wide range of viruses, including malaria, dengue, herpes simplex virus, influenza, and HIV, and distinguish various cancerous cells, holds promise for advancing biosensing applications.

Abstract A cross-equatorial low-level wind, known as Findlater Jet (FJ), modulates the thermocline in the Arabian Sea (AS) during summer monsoon (June to September). By analysing ocean and atmospheric data, we show that the FJ signal gets ‘trapped’ in the AS in the form of upper ocean heat content till the following winter months (December to February). This memory is the consequence of the combined effect of FJ-induced wind stress curl and the annual downwelling Rossby waves in the AS. During the summer monsoon months, the strong low-level westerly winds cause a negative wind stress curl in the south of the FJ axis over the central AS, resulting in a deep thermocline and high magnitude of heat being trapped. In winter monsoon months, though the wind stress curl is positive over large parts of the AS and could potentially shoal the thermocline and reduce the upper ocean heat content in the central AS, this does not happen due to two reasons. Firstly, winds are weaker, and spread over a larger area over the AS making the magnitude of the wind stress curl low. Secondly, westward propagating downwelling Rossby wave radiated from the eastern AS deepens the thermocline and prevents ventilation of the trapped heat. During the following spring, the collapse of the Rossby waves leads to the shoaling and mixing of underlying waters with surface waters thereby resurfacing of the trapped heat. The resurfacing of the trapped heat makes the AS a memory bank of the FJ induced signal.

The proposed refractive index-based biosensor made of cost-effective polymer material in Mach-Zehnder configuration with novel horizontal slot waveguide structure offers high sensitivity. Due to the recent demand for low-cost point-of-care biosensor, silicon wafer-based polymer material has the potential for developing new hybrid waveguides for sensors. Hence we designed BenzoCycloButene (BCB), SU8 material as the core, and polymethyl methacrylate (PMMA) clad on a silicon wafer. The novelty of proposed BCB and SU8 horizontal slot waveguide structure of 2.5 μ m wide and 1.8μ m thick with a slot height of 400 ​nm, which handles the analyte effectively without any external sample holder. In Mach-Zehnder Interferometer architecture, reference arm 1 ​cm and sensing arm at a length of 1.1 ​cm with analyte refractive index of cancer cell (RI ​= ​1.401) and Influenza A type virus (RI ​= ​1.48) are used. Effective mode index of BCB core and SU8 are investigated through Finite-difference time domain (FDTD) analysis, and sensitivity results are calculated. Detection of disease are plotted in the transmission spectrum with reference to normal human serum (RI ​= ​1.35). This horizontal slot waveguide of BCB core achieves a sensitivity of 19280 nm/RIU and SU8 horizontal slot core waveguide provides a sensitivity of 16500 nm/RIU, which is higher in this polymer based refractive index biosensing.

The present research is based on the thermal and flow properties of the dusty liquid past a stretching sheet. Further, the liquid flow is embedded with Methanol base fluid suspended by single walled carbon nanotubes as nanoparticles. To crack the current mathematical model problem, the numerical Runge-Kutta-Fehlberg fourth-fifth order method was used. With the aid of graphs, the effect of physical parameters on the fluid flow and thermal profile were discussed. To achieve the most accurate results, the correct initial assumptions and several non-dimensional parameter values are carefully chosen and well-adjusted. Results reveal that, the rise in values of temperature interaction parameter improves the fluid phase heat transfer but declines the dust phase heat transport. The increase in melting parameter values improves the both fluid and dust phase heat transport. The fluid phase thermal distribution drops faster than dust phase heat transfer for growing values of gamma. The growth in values of melting parameter drops the rate of heat transport.

The heat transfer in three-dimensional coordinates is the main focus of the present article. The cone-disk (CND) apparatus is presumed to include a stationary cone (SCN) and a rotating disk (RTD), or counter-rotating, or both of them co-rotating, along with Titanium dioxide-ethylene glycol-based nanofluid. The accommodative impact of nanopaprticles aggregation and thermal radiation is considered in the modelling equations for the flow pattern available in the literature. The modelling equations are converted into ordinary differential equations (ODEs) using similarity transformations. The behaviour of flow profiles is readily understood by employing the Runge Kutta Fehlberg fourth fifth-order (RKF45) method and the shooting approach, which is strategized and explained using graphs. The outcomes reveal that the dynamics of flow with nanoparticles aggregation case shows better-quality heat transport for increased values of radiation parameter. Furthermore, the fluid flow with aggregation shows the developed heat transfer rate at cone surface for increased values of radiation parameter.

Abstract Upwelling is a physical phenomenon that occurs globally along the eastern boundary of the ocean and supports pelagic fishery which is an important source of protein for the coastal population. Though upwelling and associated small pelagic fishery along the eastern Arabian Sea (EAS) is known to exist at least for the past six decades, our understanding of the factors controlling them are still elusive. Based on observation and data analysis we hypothesize that upwelling in the EAS during 2017 was modulated by freshwater-induced stratification. To validate this hypothesis, we examined 17 years of data from 2001 and show that inter-annual variability of freshwater influx indeed controls the upwelling in the EAS through stratification, a mechanism hitherto unexplored. The upper ocean stratification in turn is regulated by the fresh water influx through a combination of precipitation and river runoff. We further show that the oil sardine which is one of the dominant fish of the small pelagic fishery of the EAS varied inversely with stratification. Our study for the first time underscored the role of freshwater influx in regulating the coastal upwelling and upper ocean stratification controlling the regional pelagic fishery of the EAS.

A new enzyme-electrode is developed for the determination of ethanol by immobilizing carboxylated graphene (CG) and alcohol oxidase (AOX) on poly diallyldimethylammonium chloride (PDDA) modified graphite electrode (Gr). The biosensor showed high sensitivity and rapid detection of ethanol in the concentration range 250 μM to 1500 μM. Addition of ethanol reduced the reduction current of oxygen, which is due to the consumption of molecular oxygen for the oxidation of ethanol. The effect of temperature and pH on the performance of the biosensor has been studied. The excellent performance of the biosensor is attributed to large surface to volume ratio and high conductivity of graphene. This promotes direct electron transfer between redox enzymes and electrode surface. Low operating potential and specificity of the enzyme will restrict the interference of ascorbic acid, acetaminophen, and glucose. The biosensor was characterized by field emission scanning electron microscopy (FESEM) and cyclic voltammetry (CV) using Fe2+/Fe3+ as an electrochemical probe.

Cardiac Lipomas, accounting for 10% of primary benign cardiac tumours are usually asymptomatic, although they can sometimes be associated with a plethora of manifestations. Our patient was a 16 year old asymptomatic female with marked lipomatous hypertrophy of the interventricular septum protruding into the right ventricle, diagnosed incidentally during the ECHO evaluation for a haemic systolic murmur.

Pollution is the primary ecological threat to nature and it also raises the temperature of the Earth. The primary cause of air pollution is exhaust emissions from the combustion chamber. This study aims to focus on controlling emissions using an aqueous nanoemulsion method and to analyze positive vibrations for the reduction of pollutants in diesel engines. In this study 3% NWED (nano-based water emulsion diesel), 7% NWED, and 12% NWED emulsion blended diesel were mixed with Tween-20 as a solvent. In addition, this work was accomplished with a multiuser remote control system for the continuous monitoring of emissions with IoT technology applied to diesel engines. Experimental results have been measured with an IoT kit and five gas analyzers and reported that emission of oxides of nitrogen and hydrocarbons can be reduced by using a 7% NWED blend when compared with diesel. In addition, the experimental result also shows that the brake-specific fuel consumption is reduced with an improvement in thermal efficiency at 7% NWED when compared with other blends.

The northern Indian Ocean, comprising of two marginal seas, the Arabian Sea (AS) and the Bay of Bengal (BoB), is known for the occurrence of tropical cyclones. The simultaneous occurrence of the cyclones Luban in the AS and Titli in the BoB is a rare phenomenon, and, in the present study, we examined their contrasting upper ocean responses and what led to their formation in October 2018. Being a category-2 cyclone, the maximum cooling of sea surface temperature associated with Titli was 1°C higher than that of Luban, a category-1 cyclone. The higher tropical cyclone heat potential in the BoB compared with the AS was one of the reasons why Titli was more intense than Luban. The enhancement of chlorophyll a (Chl-a) and net primary productivity (NPP) by Luban was 2- and 3.7-fold, respectively, while that by Titli was 3- and 5-fold, respectively. Despite this, the magnitudes of both Chl-a and NPP were higher in the AS compared with the BoB. Consistent with physical and biological responses, the CO2 outgassing flux associated with Titli was 12-fold higher in comparison to the pre-cyclone value, while that associated with Luban was 10-fold higher. Unlike the Chl-a and NPP, the magnitude of CO2 flux in the BoB was higher than that in the AS. Although the cyclones Luban and Titli originated simultaneously, their generating mechanisms were quite different. What was common for the genesis of both cyclones was the pre-conditioning of the upper ocean in 2018 by the co-occurrence of El Niño and the positive phase of Indian Ocean dipole along with the cold phase of the Pacific decadal oscillation, all of which worked in tandem and warmed the AS and parts of the BoB. What triggered the genesis of Luban in the AS was the arrival of the Madden–Julian oscillation (MJO) and the mixed Rossby-gravity wave during the first week of October. The genesis of Titli in the BoB was triggered by the eastward propagation of the MJO and the associated enhanced convection from the AS into the region of origin of Titli along with the arrival of the downwelling oceanic Rossby wave.

Among the various natural hazards, landslide is the most widespread and damaging hazard. In recent times, throughout a lot of attention is being drawn to evaluate the risk due to landslides. The invention of remote sensing and GIS have been new vistas in the field of geo scientific studies viz. geomorphological mapping, groundwater potential mapping, disaster management etc. The present study has been undertaken to study different thematic maps like, contour, drainage, slope, aspect, curvature, DEM, DTM, drainage density, drainage intensity, geology, lineament, lineament density, lineament intensity, geomorphology, land use, weathering thickness, run off, soil thickness and buffer maps like road, drainage, lineament etc. in CNG ghat section, Gudalur, The Nilgiris. For this purpose, the satellite image IRS – RS2, LISS III January 2014 used to prepare different thematic maps. The contour, drainage and road network were incorporate from SoI Toposheets. The slope, curvature, aspects and buffer maps were prepared from GIS environments. Based on field studies, above said thematic maps (22 nos.) were prepared and were grouped into 3 categories viz. Geology, Hydrology and Terrain. In each category the input maps were assigned different score as well as each layer has been given different weightage. Finally the categories are analysed through multi – criteria analysis to find out 5 different vulnerability classes. The 5 different land susceptibility zones are classified as very low, low, moderate, high and very high. The percentages of area under different susceptibility classes are 3%, 20%, 51%, 25%, and 1% respectively. The locations of small area major landslides and slip locations were calculated from different years using (2010 and 2014) Trimble GPS in the field. The field data was converted into point layer in GIS and landslide inventory map was prepared. This map was superimposed in landslide susceptibility zonation map. As per field data 0%, 9.25%, 57.5%, 32% and 1.25% Slide points are come under very low, low, moderate, high, very high susceptibility zones respectively.

Plastic is a resilient, chemically inert, lightweight, and low-cost material. It sticks around in the environment for more than hundred years, threatening nature and spreading toxins. The current study deals with the use of waste polymeric materials and de oiled cake for the production of liquid oil and its blend on the performance and emission characteristics of diesel engine. The tests were conducted in an engine fuelled with diesel and four distinct blends such as 5% (B5), 10% (B10), 15% (B15), and 20% (B20), respectively. The liquid oil was produced by co-pyrolysis of neem de oiled cake (NDC) and waste polystyrene (WPS) in 1 : 2 blend ratio. The raw pyrolysis oil and its different blends were tested for their physical and chemical characteristics in order to find their suitability. Brake power (BP), brake thermal efficiency (BTE), brake-specific fuel consumption (BSFC), emissions of carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx) are used to assess the performance of the engine. The experimental results reveal that BTE at all blends is lower than diesel at all loads and the BSFC increases with increasing blend ratio and falls with increasing engine load. At higher loads, the deviation of performance and emission values from baseline diesel up to B10 is very small. It is found from the results that the liquid oil derived from NDC and WPS up to 10% blend will be the promising additive for fossil fuels.

This research work targets on the effective utilization of WTO (waste transformer oil) in a diesel engine, which would rather reduce environmental problems caused by disposing of it in the open land. The waste transformer oil was compared with the conventional diesel fuel and found that it can also be used as fuel in compression ignition engines since the WTO is also a derivative of crude oil. In this present work, the WTO has been subjected to traditional base-catalyzed trans-esterification process in order to reduce the high viscosity of the WTO which helps to effectively utilize WTO as a fuel in DI diesel engine. The objective of the work is to study the influence of injection timing on the performance, emission and combustion characteristics of a single cylinder, four stroke, direct injection diesel engine using TWTO (trans-esterified waste transformer oil) as a fuel. Experiments were performed at four injection timings (23°, 22°, 21°, and 20° bTDC). The results indicate that the retarded injection timing of 20° bTDC resulted in decreased oxides of nitrogen, carbon monoxide and unburned hydrocarbon by 11.57%, 17.24%, and 10% respectively while the brake thermal efficiency and smoke increased under all the load conditions when compared to that of standard injection timing.

The mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the oceanic primary productivity. We examined the basin-scale processes controlling the seasonal variability of mixed layer depth in the Bay of Bengal and its association with chlorophyll using a suite of in situ as well as remote sensing data. A coupling between mixed layer depth and chlorophyll was seen during spring intermonsoon and summer monsoon, but for different reasons. In spring intermonsoon the temperature-dominated stratification and associated shallow mixed layer makes the upper waters of the Bay of Bengal nutrient depleted and oligotrophic. In summer, although the salinity-dominated stratification in the northern Bay of Bengal shallows the mixed layer, the nutrient input from adjoining rivers enhance the surface chlorophyll. This enhancement is confined only to the surface layer and with increase in depth, the chlorophyll biomass decreases rapidly due to reduction in sunlight by suspended sediment. In the south, advection of high salinity waters from the Arabian Sea and westward propagating Rossby waves from the eastern Bay of Bengal led to the formation of deep mixed layer. In contrast, in the Indo–Sri Lanka region, the shallow mixed layer and nutrient enrichment driven by upwelling and Ekman pumping resulted in chlorophyll enhancement. The mismatch between the nitrate and chlorophyll indicated the inadequacy of present data to fully unravel its coupling to mixed layer processes.

Seasonal cycle of biogenic fluxes obtained from sediment trap at two locations 5°24' N, 86°46' E (southern Bay of Bengal trap; SBBT) and 3°34' N, 77°46' E (equatorial Indian Ocean trap; EIOT) within the equatorial Indian Ocean (EIO) were examined to understand the factors that control them. The sediment trap data at SBBT was collected for ten years from November 1987 while that at EIOT was for a one year period from January 1996. The characteristic of biogenic flux at SBBT was the strong seasonality with peak flux in August, while lack of seasonality characterised the flux at EIOT. The high chlorophyll biomass at the SBBT during the summer monsoon was supported by a combination of processes such as wind-mixing and advection, both of which supplied new nitrogen to the upper ocean. In contrast, the elevated chlorophyll at EIOT during summer monsoon was supported only by wind mixing. High cell counts of phytoplankton (> 5 μm) at SBBT dominated by diatoms suggest the operation of classical food web and high carbon export. On the contrary, dominance of pico-phytoplankton and one-and-a-half time higher magnitude of micro-zooplankton biomass along with 2-fold lesser meso-zooplankton at EIOT indicated the importance of microbial loop. The substantial decrease in the carbon export at EIOT indicated faster remineralization of photosynthetically produced organic matter.

Most of the e-commerce and m-commerce applications in the current e-business world, has adopted asymmetric key cryptography technique in their authentication protocol to provide an efficient authentication of the involved parties. This paper exhibits the performance analysis of distinct authentication protocol which implements the public key cryptography like RSA, ECC and HECC. The comparison is made based on key generation, sign generation and sign verification processes. The results prove that the performance achieved through HECC based authentication protocol is better than the ECC- and RSA based authentication protocols.

“Myiasis” is considered in Hindu mythology as “God's punishment for sinners.” It is known to infest live human or animal tissue. Literature abounds with reports of myiasis affecting the nasal cavity, ear, nonhealing ulcers, exophytic malignant growth, and cutaneous tissue. But report of myiasis of the tracheal stoma is rare. Only a few cases of tracheal myiasis have been reported in literature. We report a case of tracheostomal myiasis in an elderly male. The species which had infested the stoma was identified as Chrysomya bezziana, an obligate parasite. This is to our knowledge the first case report of an obligate parasite (Chrysomya bezziana) infestation of the tracheostoma from India.

Sensory integration takes place in the central nervous system where complex interactions such as co-ordination, attention, arousal levels, autonomic functioning, emotions, memory and higher level cognitive functions are carried out. Sensory integration gets information through the senses, puts it together with prior knowledge, information and memories already stored in the brain to make a meaningful response. Multi-sensory learning, as the name implies, is the process of learning a new subject matter through the use of two or more senses. This may include combining visual, auditory, tactile or kinaesthetic, olfactory and gustatory sensation. By activating brain regions associated with touch, flavour, audition and vision, they indicate a direct relationship between perceptual knowledge and sensory brain mechanisms. The investigator developed content based working memory test and pre assessment of the working memory of the students. Then researcher has developed multisensory integration model and taught though this model of science subject and find out post assessment of working memory in science. Finally investigator evaluated multisensory integration model on enhancing working memory in Science among the students.

The effect of mulching and nutrition on the growth and yield of sweet basil was examined by experimenting with four mulch treatments, viz., without mulch, black plastic, silver plastic, and organic mulch combined with four different nutrient compositions, viz., a 100% recommended dose of fertilizer (RDF), a combination of 75% RDF with humic acid, 75% RDF with microbial consortia and 75% RDF, and humic acid and microbial consortia, which served as sixteen treatment combinations with 100% RDF without mulch as a control. Among the different treatments, mulch had a significant effect on growth and yield parameters, with black plastic mulch having the maximum plant height (88.20 cm), number of branches (14.95), plant spread (5415 cm2), stem diameter (12.64 mm), fresh herbage yield (24.55 t/ha) and dry herbage yield (8.72 t/ha). Thus, the study revealed that among the various mulch treatments, black plastic mulch significantly enhanced the growth and yield parameters of sweet basil, demonstrating its efficacy in promoting optimal plant development and productivity. [ABSTRACT FROM AUTHOR]

Every teacher expects optimum level of processing in mind of them students. The level of processing is mainly depends upon memory process. Most of the students have retrieval difficulties on past learning. Memory difficulties directly related to sensory integration. In these circumstances the investigator made an attempt to construct Multisensory integration Approach Model based on sensory process and perceptual process. Multisensory Integration approach model contains three parts the first part is Instructional part, second part is processing part and third one is learning outcome part. Instructional part is includes seven steps. There are relating new information to prior knowledge, Focusing attention to the information, developing sensory connection, Organizing the information, Expanding sensory images, Structuring the information and Practicing recall. The above instructional strategies develop stimulation, sensation, Attention, Perception, Imagery, conceptualization and memory. The learning outcome part contains from low level sensory integration (visual-auditory) to high level sensory integration (Visual-Auditory-Tactile-Olfactory-Gustatory). The investigator regulates information processing of the students in brain through Multisensory Integration Approach Model.