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The present research examines the impact of Si3N4–BN hybrid reinforcement on the machinability of a magnesium hybrid composite in wire electrical discharge machine (WEDM). The composite is fabricated through inert gas assisted stir casting route with silicon nitride and boron nitride as reinforcement with varying weight percentages of 0%, 5%, and 10%. Subsequently, the fabricated composites were machined through WEDM according to Taguchi 27 orthogonal array with varying pulse on time (PON), pulse off time (POFF), wire feed rate (WFR), and wire tension (WT). The machinability of the composite was evaluated by measuring Surface Roughness (SR), Kerf Width (KW), and Cutting Velocity (CV) during WEDM. Results reveals that the % of Si3N4 has greater influence over kerf width and cutting velocity whereas BN % has higher influence over surface roughness. The optimization of process parameters using the Taguchi method resulted in different combinations of parameters for each output response. Therefore, Grey Relational Analysis was applied to determine the common optimal process parameters for all three considered output responses. The identified input parameters that yielded the higher CV, minimal SR and KW were as follows: 0% Si3N4 and BN, 6 µs PON, 14 µs POFF, 6 m/min WFR, and 10 g WT. Artificial Neural Network model has been developed to predict the output response CV, SR and KW. The 6–8–3 network model predicts the output responses with better accuracy with overall R2 value of 99.3%. [ABSTRACT FROM AUTHOR]

Human Activity Recognition (HAR) using smartphone sensors has been identified as a significant emerging research domain. Its application areas exhibit the performance from the intelligent tailored activity monitoring. Researchers have proposed various HAR models to recognize the human activity patterns using traditional smartphone sensor data. In addition, embedding contextual information such as data availability, sensing device orientation, body part location, axis layout, and more makes a fruitful impact on the quality of activity sensor data. The research challenge occurred due to the lack of contextual information in sensor data, leading to activity patterns ambiguity. Often, the motion sensor was separately used to acquire contextual information that consumes unnecessary computational resources. In this paper, we have used activity sensor data availability as contextual information. The proposed Deep Context Model (DCM) recognizes the activity pattern in the dual context-attention mode, i.e., static and dynamic context. The proposed model consists of convolutional and recurrent networks that find the associated activity patterns in a dual context. The convolutional networks are excellent for automatic feature extraction in a static context, whereas recurrent networks are used in a dynamic context for memorizing patterns. We evaluated the performance of the proposed model using the open accessible KU-HAR dataset. The experimental outcomes revealed that DCM has achieved the F1 score of 98.96% and 99.62% for static and dynamic context, respectively. Further, the robustness and applicability of the proposed model have been gauged using the HHAR dataset. [ABSTRACT FROM AUTHOR]

Hilbert's Tenth Problem asks whether there is an algorithmic procedure to solve Diophantine equations (polynomial equations with integer coefficients) for integer solutions. This famous problem was shown to be unsolvable by Yuri Matiyasevič in 1970. In other words, there is no algorithm that can decide in general whether a given Diophantine equations has integer solutions or not. This negative solution builds on a long line of work by Martin Davis, Hilary Putnam, and importantly, Julia Robinson. In this article, we briefly describe the problem, its unsolvability, and Julia Robinson's contribution. [ABSTRACT FROM AUTHOR]

A new method has been proposed for the green and efficient synthesis of xanthenediones and their corresponding open-chain analogs aryl-methylene bis(3-hydroxy-5,5'-dimethyl-2-cyclohexene-1-ones) using natural acid, Lemon juice, as the catalyst. This method involves the use of lemon juice as a surfactant-type bronsted acid, which makes it non-polluting and produces a high-purity product with excellent yield. Additionally, the work-up procedure is clean and straightforward. Dimedone and aldehydes are the starting materials for this process. [ABSTRACT FROM AUTHOR]

Herein, we report the novel protocol for synthesizing bimetallic gold and palladium nanoparticles decorated on rigid and stable cerium oxide support using aloe vera extract. The Au–Pd@CeO2 catalyst was found to be effective for the Buchwald–Hartwig C–N cross-coupling reaction and amination of benzyl alcohol due to the synergistic influence generated by Au and Pd metals. The prepared catalyst was characterized by using XRD, TEM, SEM, and EDS. The catalyst can be efficiently used for a diverse range of substrates in the Buchwald–Hartwig C–N cross-coupling and amination of benzyl alcohol reactions compared to previously described protocols. The catalyst retains its catalytic activity even after seven cycles. The synthesis of bimetallic gold and palladium nanoparticles decorated on cerium oxide support using aloe vera extract. The Au-Pd@CeO2 catalyst was found to be effective for Buchwald–Hartwig C-N cross-coupling and amination of benzyl alcohol reactions due to the synergistic effect generated by Au and Pd metals. [ABSTRACT FROM AUTHOR]

2-Aminoanilinium benzene-1, 2-diaminium tris (4-methylbenzene-1-sulfonate) organic single crystal was grown by slow evaporation solution growth technique at ambient temperature. The grown crystal was subjected to single-crystal X-ray diffraction studies to confirm the crystal structure. The presence of different molecular groups and modes of vibrations was identified by FTIR analysis. UV- visible spectral studies revealed the transparency, lower cut-off wavelength, bandgap energy, optical parameters such as refractive index (n), extinction coefficient (k), optical conductivity, and electrical conductivity. Laser-induced damage threshold was calculated as 3.5 GW/cm2. Mechanical properties of grown crystal were investigated by Vicker’s micro-hardness test. The dielectric measurement at room temperature showed the electrical behavior of the crystal. [ABSTRACT FROM AUTHOR]

This study investigated the convective heat transfer coefficient and friction coefficient in a copper helical double pipe heat exchanger utilizing biosynthetic aqua-based silver (Ag) nanofluids prepared with Histiopteris incisa leaf extract. The nanofluids were characterized using UV–Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy. The experimental approach involved the constant heat flux method under laminar flow conditions with flow rates ranging from 100 to 160 litres per hour (LPH). Biosynthesized aqua-based silver nanofluids were synthesized using a one-step biosynthesis method, resulting in volume concentrations ranging from 0.3 to 0.9%. Our findings demonstrated that the biosynthesized aqua-based silver nanofluids exhibited enhanced convective heat transfer compared to pure water. Additionally, the heat transfer coefficient showed an increasing trend with higher volume concentrations of biosynthesized aqua-based silver nanofluids. Notably, the most significant improvement in convective heat transfer, reaching 40%, was achieved with a 0.9% volume concentration of biosynthesized aqua-based silver nanofluids, a flow rate of 140 LPH, and a Dean number of 1400. Moreover, the friction coefficients observed for biosynthesized aqua-based silver nanofluids were 35% higher than those of water in the Dean number range of 1400–2400. [ABSTRACT FROM AUTHOR]

Vehicle detection and classification in real world highly congested traffic scenario is an important yet difficult task, especially because surveillance footage is captured in low resolution. Most available datasets contain high quality images and the models developed based on them do not perform well in real world scenario. In this paper, we present a Convolution Neural Network (CNN) based approach for vehicle type classification in congested vehicle traffic scenario with low resolution surveillance images. We have used highly congested low resolution CityCam dataset. To improve the classification performance of the proposed model, image super resolution technique is adopted to enhance essential details needed for differentiating classes. The experimental results demonstrate that the proposed CNN model performs better on the dataset compared with other existing state of art deep learning models. The proposed model achieved higher accuracy of 87.56% over the state of art models VGG16 and Inceptionv3 which achieves 84.62% and 84.87% respectively. Further, by enhancing the dataset with Residual Dense Network based image super resolution technique, the classification accuracy has increased around 1.73% to 89.29%. [ABSTRACT FROM AUTHOR]

Offering remedial measures to the catastrophic problem of pollution has become the clarion call such that photocatalytic degradation could be an asset for this cause. In this study, pure SnO2, ZnO and SnO2/ZnO nanocomposites were prepared by facile sol-gel method. The structural properties of the samples were investigated by XRD analysis. In order to determine the stability and credibility of the samples, crystallite size, strain and dislocation density were determined by advocating the Williamson–Hall (W–H) method. FE-SEM analysis reveals a sphere-like morphology for the samples. HR-TEM analysis evidenced the formation of SnO2/ZnO heterojunction nanocomposite. The surface area and pore size distribution of the samples were obtained from N2 adsorption-desorption analysis. Chemical states of elements were obtained by X-ray-photoelectron Spectroscopy (XPS). The Raman study further established the formation of SnO2/ZnO nanocomposite. The optical band gaps of the samples were estimated by the Tauc relation as 3.51 eV for SnO2 and 3.08 eV for ZnO and SnO2/ZnO nanocomposites. From the PL spectra, a weakening of peak intensity is observed for the composite sample. The surface charge of the prepared nanoparticles was investigated by Zeta potential measurements. SnO2/ZnO photocatalyst displayed 90 % degradation efficiency towards crystal violet effluent while SnO2 and ZnO displayed 47 % and 65 % degradation efficiencies, respectively. This character was rationalized in terms of better charge separation and suppression of charge recombination in the SnO2/ZnO photocatalyst such that it can be utilized as a prospective material to minimize water pollution in a cost-economical way. [ABSTRACT FROM AUTHOR]

Recently, inter-mixed alumina, zirconia, and yttria-based nanoceramic composites have been widely used for medical implants and thermal barrier coatings, including tribology applications, due to their high tribo-thermal, chemical, and structural phase stability. The present investigation deals with nanolubricant with hollow spherical inter-mixed alumina yttria-stabilized zirconia (AYSZ) nanoceramic composite as an additive. The AYSZ/SAE20W40 nanolubricant was prepared at two different mass percentages (0.22 and 0.33 mass% of NPs) using the ball milling method. The hollow spherical AYSZ nanocomposite particles were broken into nanopot pieces due to impact and frictional forces between the ceramic balls during the attrition process. The broken pot-like AYSZ nanopieces in nanolubricant showed good dispersive stability due to the increased surface area. The prepared AYSZ/SAE20W40 nanolubricant samples were investigated for their tribological properties, such as frictional coefficient, frictional force, wear, and specimen mass loss, including thermal conductivity. The results for nanolubricant with 0.33 mass% of AYSZ samples showed better wear reduction (106.10%) and thermal conductivity (1.38%) than 0.22 mass% and SAE20W40 engine oil. Hence, the AYSZ nanoceramic was proven as a nanoadditive for lubricant tribo-thermal application by reducing the boundary lubrication wear. [ABSTRACT FROM AUTHOR]

A highly efficient and convenient green method using highly efficient natural catalyst calcined eggshell (CES) is described for synthesis of 2-amino 4H-chromene derivatives in ethanol–water system. The new inexpensive green catalyst CES is obtained from waste natural resources. This method offers mild reaction conditions at ambient temperature, with short reaction times and clean work up procedures. This is an economical and green alternative for existing methodologies. [ABSTRACT FROM AUTHOR]

Chlorella vulgaris has a high lipid content with potential for biofuel application. With a rapid growth cycle and ease of culture, it is well suited for observing lipid profile changes and connecting this with phytohormone responses at a cellular level. The present study profiled C. vulgaris endogenous phytohormone levels in nutrient rich media and determined how exogenous phytohormone application affected its lipid metabolism. Endogenous phytohormone profiling using high-resolution liquid chromatography-tandem mass spectrometry revealed methylthiolated cytokinins as the most dominant cytokinin form produced. The impact of exogenous benzyladenine, trans-zeatin, 2-methylthio-trans-zeatin, and abscisic acid at three concentrations (10–7, 10–6 and 10–5 M) was assessed using daily growth monitoring via optical density (OD680). Extraction and assessment of total lipid content followed the Soxhlet method, and fatty acid measurements of five fatty acids (α-linolenic, linoleic, palmitic, oleic, and stearic acids) was done using gas chromatography equipped with a flame ionization detector. Growth stimulation was the highest at 10–6 M for all exogenous phytohormones except trans-zeatin, which was most effective at 10–5 M. All exogenous treatments caused changes in fatty acid methyl ester (FAME) content, especially benzyladenine at 10–6 M. For α-linolenic acid, the most significant change occurred with the addition of 10–7 and 10–6 M 2-methylthio-trans-zeatin, resulting in its increased production by 141% and 381%, respectively. This is the first report of 2-methylthio-trans-zeatin supplementation in microalgal cultures to date. The results presented suggest that using 2-methylthio-trans-zeatin exogenously can enhance α-linolenic acid production for pharmaceutical or industrial purposes. [ABSTRACT FROM AUTHOR]

A vibrant non-linear optical single crystal of cadmium chloride doped L-alanine p-toluene sulfonic acid (LAPTCd) was grown by slow evaporation. XRD analysis was carried out and obtained the cell parameter for the grown crystal. The grown LAPTCd crystal belongs to the orthorhombic crystal system with non-centro symmetric space group P212121. The presence of the dopant was confirmed from an energy dispersive X-ray analysis. FT-IR and FT-Raman spectra were recorded and the presence of different functional groups and vibrations confirmed in the grown crystal. The UV–Vis–NIR absorption and transmittance spectrum shows that the crystal has a good optical transparency within the range 200–800 nm. The optical parameters have also been calculated, and it has a lower wavelength cutoff at around 235 nm. The optical energy band gap of the crystal was calculated from Tauc's Plot and it is 5.24 eV. The fluorescence spectrum of the crystal reveals that the excitation wavelength is 489.97 nm. The thermal stability and the melting point of the crystal were analyzed by TG/DTA. The efficiency of second harmonic generation of the LAPTCd crystal is found to be 0.7 times more that of KDP crystal. [ABSTRACT FROM AUTHOR]

The recognition of human activities has become a dominant emerging research problem and widely covered application areas in surveillance, wellness management, healthcare, and many more. In real life, the activity recognition is a challenging issue because human beings are often performing the activities not only simple but also complex and heterogeneous in nature. Most of the existing approaches are addressing the problem of recognizing only simple straightforward activities (e.g. walking, running, standing, sitting, etc.). Recognizing the complex and heterogeneous human activities are a challenging research problem whereas only a limited number of existing works are addressing this issue. In this paper, we proposed a novel Deep-HAR model by ensembling the Convolutional Neural Networks (CNNs) and Recurrent Neural Networks (RNNs) for recognizing the simple, complex, and heterogeneous type activities. Here, the CNNs are used for extracting the features whereas RNNs are used for finding the useful patterns in time-series sequential data. The activities recognition performance of the proposed model was evaluated using three different publicly available datasets, namely WISDM, PAMAP2, and KU-HAR. Through extensive experiments, we have demonstrated that the proposed model performs well in recognizing all types of activities and has achieved an accuracy of 99.98%, 99.64%, and 99.98% for simple, complex, and heterogeneous activities respectively. [ABSTRACT FROM AUTHOR]

India achieved the goal of a circular economy towards regenerative, value-creating development and growth for long-term prosperity. But at the same time, due to the recent unprecedented urbanization and industrialization, wastes and pollutants generated from these activities are enormous, which causes water, air and soil pollution. For example, brine sludge is one of the large quantities of waste from the chlor-alkali industry. This paper reviews different environmental impacts of waste minimization of brine sludge from the chlor-alkali industry with current treatment and utilization technologies. Various materials developed like paver blocks, bricks, non-toxic radiation shielding materials, cement-free materials, etc., using brine sludge as resource material, which can be helpful for broad application spectrum. Conventional softening, Ion exchange, and membrane technologies are available to remove solute from brine sludge. For the salt content in brine sludge, resins' uses are most economical and immensely practical. Due to high-quality recovery with power generation and environmentally friendly brine treatment, membrane-based technologies like membrane distillation, forward osmosis, and electrodialysis can be preferred. In the future perspective, recent membrane technologies like pressure-retarded osmosis and reverse electrodialysis are used to generate power from the salinity gradient between waste brine and freshwater. [ABSTRACT FROM AUTHOR]

The magnetically separable heterogeneous nickel–zinc ferrite (NiZnFe2O4) catalyst was synthesized and used for the first time as an environmentally friendly reusable catalyst for the synthesis of 2-amino-4H-chromene derivatives via a one-pot, three-component condensation reaction of various salicylaldehydes and malononitrile or ethyl cyanoacetate with nitromethane or nitroethane in ethanol at room temperature. There have been no reports of nickel zinc ferrite being used as a catalyst. The catalyst was specified by using several techniques, including DSC–TGA, FT-IR, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), BET, and scanning electron microscope (SEM). The present protocol suggests some benefits, which include green reaction conditions, simple reaction work-up, short reaction time, excellent product yields, chromatography-free purification, and high efficiency of the heterogeneous catalyst. More importantly, this catalyst was recovered from the reaction mixture using a simple external magnet, and it was reused successively at least seven times without any significant loss of catalytic activity. [ABSTRACT FROM AUTHOR]

The importance and utilization of advanced thermal insulating materials increase due to their broad and irreplaceable energy conservation role. This paper describes the novel way of achieving insulating material. In two waste by-products, namely rice husk ash (RHA), agriculture waste, and marble waste powder (MWP), industrial waste has been utilized to make asbestos-free advanced material for thermal insulation. A novel method for making asbestos-free advanced material for thermal insulation using RHA and marble waste's inherent characteristics has developed mechano-chemical for appropriate physico-chemical consolidation, densification, and ceramic processing route. The Si and Ca sources undergo a series of chemical transformations accompanied by mass transfer and thermal reactions during the synthesis process. The formation of this silicate compound occurs due to the presence of higher contents of CaO in marble waste powder (MWP) and silica in rice husk ash (RHA), resulting in thermal insulating characteristics in the advanced thermal insulation material (ATIM). Raman spectra of ATIM after heating at 1100 °C were mainly amorphous, which had a broad peak at 1072 cm−1. This shows thermal transformation occurs after the heating process, the admixture of tailored powder, and fly ash (FA). The density of the ATIM is found to be 1150 kg/m3. The phase transformation (glass transition temperature) was found in all the samples between 600 and 800 °C. The mechanical properties, namely the compressive strength and impact strength evaluation test, showed that the material meets the standard specifications for ceramic tiles. The thermal conductivity (W/mK) was calculated from different temperature 30, 50, 100,150, and 200 °C and found to be 0.571, 0.541, 0.516, 0.498, and 0.477, respectively. According to the test results, it is concluded that ATIM from MWP, RHA, and FA were excellent insulating components. The novel feature of the reported process is the development of non-toxic and asbestos-free thermal insulating low-cost material wherein chemically designed and mineralogically formulating desired phases lead to the homogeneous and effective thermal insulating matrix. The process is feasible, simple, cheap, and highly energy-efficient, increases production efficiency, and is environmentally friendly. The widespread use of advanced material for a broad application spectrum ranges from aerospace, automobile, electronics, transportation, construction, to other industries. [ABSTRACT FROM AUTHOR]

Purpose: Fetal echocardiography is widely used for the assessment of fetal heart development and detection of congenital heart disease (CHD). Preliminary examination of the fetal heart involves the four-chamber view which indicates the presence of all the four chambers and its structural symmetry. Examination of various cardiac parameters is generally done using the clinically selected diastole frame. This largely depends on the expertise of the sonographer and is prone to intra- and interobservational errors. To overcome this, automated frame selection technique is proposed for the recognition of fetal cardiac chamber from fetal echocardiography. Methods: Three techniques have been proposed in this research study to automate the process of determining the frame referred as "Master Frame" that can be used for the measurement of the cardiac parameters. The first method uses frame similarity measures (FSM) for the determination of the master frame from the given cine loop ultrasonic sequences. FSM makes use of similarity measures such as correlation, structural similarity index (SSIM), peak signal to noise ratio (PSNR), and mean square error (MSE) to identify the cardiac cycle, and all the frames in one cardiac cycle are superimposed to form the master frame. The final master frame is obtained by considering the average of the master frame obtained using each similarity measure. The second method uses averaging of ± 20% from the midframes (AMF). The third method uses averaging of all the frames (AAF) of the cine loop sequence. Both diastole and master frames have been annotated by the clinical experts, and their ground truths are compared for validation. No segmentation techniques have been used to avoid the variability of the performance of various segmentation techniques. All the proposed schemes were evaluated using six fidelity metrics such as Dice coefficient, Jaccard ratio, Hausdorff distance, structural similarity index, mean absolute error, and Pratt figure of merit. Results: The three proposed techniques were tested on the frames extracted from 95 ultrasound cine loop sequences between 19 and 32 weeks of gestation. The feasibility of the techniques was determined by the computation of fidelity metrics between the master frame derived and the diastole frame chosen by the clinical experts. The FSM-based identified master frame found to closely match with manually chosen diastole frame and also ensures statistically significant. The method also detects automatically the cardiac cycle. The resultant master frame obtained through AMF though found to be identical to that of the diastole frame, the size of the chambers found to be reduced that can lead to inaccurate chamber measurement. The master frame obtained through AAF was not found to be identical to that of clinical diastole frame. Conclusion: It can be concluded that the frame similarity measure (FSM)–based master frame can be introduced in the clinical routine for segmentation followed by cardiac chamber measurements. Such automated master frame selection also overcomes the manual intervention of earlier reported techniques in the literature. The fidelity metrics assessment further confirms the suitability of proposed master frame for automated fetal chamber recognition. [ABSTRACT FROM AUTHOR]

This study reports the 222Rn, 220Rn, and their progeny concentration in Shivamogga district by using SSNTD's based pin hole dosimeters and deposition-based progeny sensor. The average indoor 222Rn and 220Rn concentration varies from 8.14 to 146 Bq m−3 and 13.01 to 157 Bq m−3 with a mean value of 60.61 and 61.77 Bq m−3. The EEC for 222Rn and 220Rn ranges from 1.55 to 19 Bq m−3 and 0.44 to 6 Bq m−3 with a mean value of 7.29 and 2.66 Bq m−3. The annual average equilibrium factor for 222Rn is well within the global mean values of 0.4, while the thoron is bit higher than specified global mean values of 0.02. The annual effective dose varies from 0.31 to 2.5 mSvy−1 with a mean value of 1.1 mSvy−1. [ABSTRACT FROM AUTHOR]

In this study, a modified catalytic converter was employed to treat the harmful exhaust gas pollutants of a twin-cylinder, four-stroke spark-ignition engine. This research mainly focuses on the emission reduction of unburnt hydrocarbons, carbon monoxide, and nitrogen oxides at low light-off temperatures. A sucrolite catalyst (sucrolite) was coated over the metallic substrate present inside the catalytic converter, and exhaust gas was allowed to pass through it. A scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectroscopy were used to investigate the changes in morphology, chemical compounds, and functional group elements caused by the reactions. Catalytic reactions were studied by varying the engine loads and bed temperatures, and the results were compared with those of the commercial catalytic converter. The results show that sucrose present in the catalyst was suitable at low temperatures while alumina was suitable for a wide range of temperatures. In the case of the modified catalytic converter, the maximum catalytic conversion efficiencies achieved for oxidizing CO and HC were 70.73% and 85.14%, respectively, and for reduction reaction at NOx was 60.22% which is around 42% higher than in commercial catalytic converter. As a result, this study claims that sucrolite catalyst is effective for low-temperature exhaust gas. [ABSTRACT FROM AUTHOR]

The present investigation deals with production of biochar using various agricultural and non-agricultural waste biomass followed by sorption of methylene blue (MB) dye. The optimization of pyrolysis temperature, dye solution pH, incubation temperature, and time was performed using response surface methodologies (RSM). Analytical tools like Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and total organic carbon (TOC) were employed to analyze changes in the material after pyrolysis. The water hyacinth biochar showed 100% predicted and 98% actual sorption capability for MB dye (3000 mg/L) after statistically optimized conditions like pyrolysis temperature (1000 °C), pH (8), incubation temperature (60 °C), and incubation time (1 h). The cytotoxicity, phytotoxicity, and hemolysis studies indicated that the toxicity of the MB dye was significantly decreased after treating MB dye solution with water hyacinth biochar. Therefore, the present results reveal an easy and economical dye removal strategy using various waste biomass-derived biochars. [ABSTRACT FROM AUTHOR]

Photovoltaic performance of a marine red seaweed Gracilaria corticata using acetone and methanol as extracting solvents was examined in a dye-sensitized solar cell (DSSC) integrated with TiO2 photoanode. The UV–vis absorption spectra and TLC analysis revealed the presence of natural photosynthetic pigments, such as chlorophyll a, chlorophyll b, pheophytin, and xanthophylls. DSSC performance parameters, such as short-circuit current density (Jsc) and open-circuit voltage (Voc), were directly measured from each current–voltage (J–V) characteristic curve, while the remaining photovoltaic parameters such as maximum current density (Jmax), maximum voltage (Vmax), maximum power (Pmax), fill factor (FF), and overall cell conversion efficiency (η) were calculated from the respective J–V characteristic curve. It is peculiar to note that DSSCs in both solvents disclosed a reasonably fill factor (FF). However, DSSCs sensitized by acetone extract of G. corticata exhibited relatively high photovoltaic performance (Jsc 0.82 mA cm2, Voc of 702 mV, impressive FF (0.73) and an efficiency of 0.42%), which was twofold higher than the DSSCs sensitized by methanol extract (efficiency 0.18%). The results suggest the use of seaweed pigments as low cost, eco-friendly viable to alternate DSSC. [ABSTRACT FROM AUTHOR]

In the present research, the coconut endocarp shell as a natural waste was converted into a valuable non-conventional catalyst by a simple thermal treatment, namely coconut endocarp shell ash (CESA). The prepared CESA was characterized using several analytical techniques, including TGA, FT-IR, XRD, BET, SEM, and EDX. The catalytic property of the CESA was examined in the synthesis of pharmaceutically active 2-amino-4H-benzochromene derivatives via one-pot three-component condensation of aldehydes, malononitrile, and α or β-naphthol in ethanol at room temperature. The most promising aspects of the presented approach are the high catalytic efficiency, short reaction time, excellent yield of products, operational simplicity, waste to wealth, and optimization with the design of experiment. Moreover, the CESA catalyst was recycled five times without any apparent loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Almost all aspects of society from food security to disease control and prevention have benefited from pharmaceutical and personal care products, yet these products are a major source of contamination that ends up in wastewater and ecosystems. This issue has been sharply accentuated during the coronavirus disease pandemic 2019 (COVID-19) due to the higher use of disinfectants and other products. Here we review pharmaceutical and personal care products with focus on their occurrence in the environment, detection, risk, and removal. [ABSTRACT FROM AUTHOR]

The growths in e-mobility are the factor that impetus the research in lightweight material with improved mechanical properties, especially strength. The research concentrates on developing a novel metal matrix nano-composite of high-quality AA8011 aluminium alloy reinforced with varying weight percentages of nano-particles of B4C (0, 0.3, 0.6, 0.9, 1.2 and 1.5 wt%). The high-energy electromagnetic frequency stir casting technique was used to fabricate nano-composite, which enhanced the wetting of matrix and reinforcement. The rupture strength of nano-composite primarily hinges on the structure and formation of nano-composite. The morphology and distribution of nano-particles in metal matrix nano-composites (MMNC) were characterized by using Field Emission Scanning Electron Microscope. The yield strength, yield point, tensile strength, elongation, and reduction of area of MMNC under uniaxial tensile stresses were determined by Universal Testing Machine. The machine learning algorithms automatically characterized the fractured material texture in conjunction with the described techniques. The unique textural information extracted from each fractured sample distinguished the surfaces as agglomeration, brittle and ductile texture. The fractography analysis of MMNCs revealed the transition of composite from cup and cone to cleavage fracture, which ensured the property change of matrix by the addition of nano-reinforced particles. [ABSTRACT FROM AUTHOR]

In this study, a novel synthetic method for cobalt oxide (Co3O4) nanoparticles using Bos taurus (A-2) urine as a reducing agent was developed. In addition to this ZnO nanorods were produced hydrothermally and a nanocomposite is formed through a solid-state reaction. The synthesized materials were characterized through modern characterization techniques such as XRD, FE-SEM with EDS, DLS, zeta potential, FT-IR, Raman spectroscopic analysis, and TGA with DSC. The free radical destructive activity was determined using two different methods viz. ABTS and DPPH. The potential for BSA denaturation in vitro, which is measured in comparison to heat-induced denaturation of egg albumin and results in anti-inflammatory effects of nanomaterial was studied. All synthesized nanomaterials have excellent antibacterial properties, particularly against Salmonella typhi and Staphylococcus aureus. The composite exhibits excellent antioxidant and anti-inflammatory activities in comparison to pure nanomaterials. This reveals that these nanomaterials are advantageous in medicine and drug administration. [ABSTRACT FROM AUTHOR]

Smoke detection is an advance caution to the unforeseen great damage events. Therefore, it is required to identify the smoke in the course of initial stages for preventing fire events. A new technique is proposed to lessen the rate of incorrect alarm by identify the smoke and examine its distinctive texture attributes. Initially, the smoke-colored regions are segmented based on color at the YUV color locality. Then the tentative frame differencing is used to segment the candidate smoke region from the smoke-colored region. In the next phase, the candidate distinctive texture attributes in the smoke region are extracted using Co-occurrence of Hamming Distance based Local Binary pattern (CoHDLBP) and Co-occurrence of Local Binary pattern (CoLBP); these features include homogeneity, energy, correlation and contrast. Finally, the ELM classifier is proficient for the take-out features from the candidate smoke region, and then the decision has been taken with the assistance of a smoke alarm. Investigational outcomes proved that the suggested smoke recognition process executes better compared with all the usual smoke recognition methods by achieving better detection accuracy and processing time. [ABSTRACT FROM AUTHOR]

The Immunoscore is a method to quantify the immune cell infiltration within cancers to predict the disease prognosis. Previous immune profiling approaches relied on limited immune markers to establish patients' tumor immunity. However, immune cells exhibit a higher-level complexity that is typically not obtained by the conventional immunohistochemistry methods. Herein, we present a spatially variant immune infiltration score, termed as SpatialVizScore, to quantify immune cells infiltration within lung tumor samples using multiplex protein imaging data. Imaging mass cytometry (IMC) was used to target 26 markers in tumors to identify stromal, immune, and cancer cell states within 26 human tissues from lung cancer patients. Unsupervised clustering methods dissected the spatial infiltration of cells in tissue using the high-dimensional analysis of 16 immune markers and other cancer and stroma enriched labels to profile alterations in the tumors' immune infiltration patterns. Spatially resolved maps of distinct tumors determined the spatial proximity and neighborhoods of immune-cancer cell pairs. These SpatialVizScore maps provided a ranking of patients' tumors consisting of immune inflamed, immune suppressed, and immune cold states, demonstrating the tumor's immune continuum assigned to three distinct infiltration score ranges. Several inflammatory and suppressive immune markers were used to establish the cell-based scoring schemes at the single-cell and pixel-level, depicting the cellular spectra in diverse lung tissues. Thus, SpatialVizScore is an emerging quantitative method to deeply study tumor immunology in cancer tissues. [ABSTRACT FROM AUTHOR]

Biotic stresses cause severe yield reductions in rice and are a threat to global food security. Developing resistant cultivars is the most affordable and sustainable approach to handling different biotic stresses. CO43 is an elite rice variety of Tamil Nadu susceptible to gall midge (GM) and bacterial blight (BB). In this regard, the current research was carried out to pyramid a major BB resistance gene xa13 into the background of the improved CO43 carrying two major genes for GM resistance Gm1 and Gm4. The improved CO43 was crossed with the donor line B95-1 X Abhaya, carrying the BB resistance gene xa13 and GM resistance gene Gm4. Marker-assisted backcross breeding was employed to develop three gene-pyramided homozygous BC3F3 lines (Gm1Gm1 + Gm4Gm4 + xa13xa13). Foreground selection was done at every generation using the functional marker xa13-prom for selecting the xa13 gene and the SSR markers RM1328 and RM22550 for targeting the Gm1 and Gm4 genes, respectively. The selected BC3F3 lines were highly resistant to GM and BB. Agronomical and grain quality evaluation of the selected lines led to the identification of two lines, C39-24-11 and C39-24-127 having yield on par with the improved CO43. The selected lines will be further pyramided with additional BB and blast resistance genes to develop improved lines with durable resistance against multiple biotic stresses of rice. [ABSTRACT FROM AUTHOR]

A simple and eco-friendly protocol for the facile synthesis of tetrahydrobenzo[b]pyran and 1,4-dihydropyridine derivatives was developed using naturally sourced coconut endocarp shell ash (CESA) as a catalyst at room temperature in eco-compatible solvent system. The CESA catalyst was obtained from renewable feedstock, biodegradable waste, by simple thermal treatment on coconut endocarp shell (CESA), and the formation of its catalytic phase was characterized by DSC-TGA, FT-IR, XRD, EDX, BET, and SEM techniques. Derivatives of tetrahydrobenzo[b]pyran and 1, 4-dihydropyridine are obtained with an excellent yield, ranging from 82 to 99% in shorter reaction times. The remarkable advantages of the process presented here are that it is operationally clean, environmentally benign, and the product does not require chromatographic separation. Furthermore, the catalyst can be recovered conveniently and reused five times without significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

The estimated mean value of activity of radionuclides (226Ra, 232Th, and 40K) in the forest environment of Shankaraghatta are 11.52 ± 1.6, 19.94 ± 2.08 and 164.67 ± 3.2 Bq kg−1 for soil, and for building materials 48.53 ± 1.99, 63.20 ± 2.48 and 470.47 ± 6.59 Bq kg−1 respectively. The average indoor and outdoor Gamma Absorbed Dose rate and total Annual Effective Dose rate are less than the global average values. The forest ecosystem influenced in reducing the natural ambient gamma radiation levels. The constructions materials used for roads enhanced it. The entire measured hazard indices are far below the criterion limit of unity except pink granite and ceramic tiles contains higher activity of radionuclides. [ABSTRACT FROM AUTHOR]

Due to urbanization and industrialization pollution level increases. Air pollution directly affects to human health. Air Quality Indices (AQI) method is related to measuring the concentration of different pollutants PM10, NO2, SO2 and other pollutants. The fuzzy Logic air quality index calculates in single value of AQI defines limits 0 to 1. In this study, a comparison of air quality data of three cities was conducted with the help of fuzzy logic algorithm. It used to evaluating Indices through fuzzy multi criteria decision making (MCDM) framework in which linguistic terms of experts opinion and perception, accordingly computing matrix is constructed for sub criteria. There are five linguistic terms used in this framework to create membership functions such as high significant, significant, average significant, low significant and not significant. The three cities, Bangalore, Mysore, and Hubli-Dharwad air quality datas was taken for analysis and evaluating indices during pre-COVID years (2017, 2018, and 2019). The AQI value shows that Bangalore has the highest pollution level while Mysore has the lowest. Using the fuzzy theory, results show that Bangalore and Hubli-Dharwad decrease in pollution level by -0.074921% and -0.04797%. Negative sign shows the decrease pollution level while Mysore increase pollution level by 0.011792%. Overall the results show that AQI of Mysore city is low compared to Bangalore and Hubli-Dharwad. Also, this study reveals air quality disseminated through industrial processes and automobile emissions in India cities during pre-COVID pandemic years. [ABSTRACT FROM AUTHOR]

Hybrid fiber-reinforced polymer nano-biocomposites were prepared from flax fiber, aloe vera fiber, polyamide 6 (PA6), and organically modified montmorillonite (OMMT) through the hot-pressing method. The effect of TAF/TFF/OMMT with PA6 content on mechanical, thermal, water absorption, and biodegradability properties was investigated. The coefficient of friction of neat-PA6 (Testing conditions: Load of 10 to 30 N, sliding distance of 1000 m, sliding velocity of 1 to 3 m/s) was measured. The improvement in mechanical, water resistance and thermal properties are achieved in PA6/10%(TFF/TAF)/1%OMMT nano-biocomposite compared to neat-PA6. The desired TFF/TAF/OMMT combination shows improvement of strength of material due to filling pores with fine fibers content, and Si-content in OMMT clay leads to increased strength. Microstructural morphology reveals that crack propagation minimizes with an increase in OMMT content. [ABSTRACT FROM AUTHOR]

Energy utilization in building sector constitutes 40% of the total energy consumption of the world, and in this, the wall alone consumes 50% of the buildings' energy. Hence, in order to reduce energy cost and to maintain the thermal comfort inside a room, a novel wall construction method is suggested and its heat transfer characteristics are studied at different wall temperatures. The energy consumption required for room cooling got decreased by the use of this novel method, and also, the material requirements were found to be reduced about 12% for constructing the wall. To improve thermal resistance, the air gap is provided in the brick wall structure by placing the bricks in such a way that an air gap is formed in the middle. By this arrangement, 35% of the heat transfer surface area gets covered by the air gap. The heat transfer rates across the traditional solid wall and also the modified hollow wall were investigated for five test conditions ranging from 303 to 323 K in the step of 5 K. Using the hollow wall, the maximum reduction in the total heat flux found was 40.59 Wm−2 which is about 26% lower than the solid wall. Hence, the hollow wall would be an energy-saving structure compared to solid wall. [ABSTRACT FROM AUTHOR]

The different percentages of boron carbide (B4C) reinforced Magnesium metal matrix composites were processed using Powder Metallurgy method. The characterizations are performed by Scanning Electronic Microscope (SEM), X-ray Diffraction pattern, Electron Backscattered Diffraction, and Energy Dispersive Spectrum. The texture analysis of the composites is conducted via an image processing method. Wear tests are executed in the dry sliding state under ambient room conditions. The three levels Box-Behnken design of Response Surface Methodology has been selected to create the mathematical models for the three variables (weight percentage of B4C, sliding velocity, and load) to predict the responses namely specific wear rate (SWR) and coefficient of friction (COF). The developed model is validated and analyzed through the Analysis of variance (ANOVA). This model has a 95% efficient confidence to forecast the COF and SWR. The worn surface features are extracted and analyzed through an image processing technique. The roughness measurement of the worn surfaces is executed via Atomic Force Microscopy analysis. [ABSTRACT FROM AUTHOR]

A green, highly efficient, and eco-friendly protocol for Knoevenagel–Michael addition reaction is reported in Chickpea leaf exudates (CLE) as a naturally sourced biosurfactant. The reactions between dimedone/4-hydroxycoumarins and a variety of aryl aldehydes were carried out in presence of CLE to afford diketodiols/biscoumarins. The synthetic pathway complies with several key requirements of green chemistry principles such as the employment of natural feedstock as green reaction media, ambient temperature, atom economy along with natural biosurfactant type Bronsted acids, and recyclable and biodegradable catalyst which led to a 28-fold increase in molar efficiency versus industrial standard protocols. Its dynamic phase is confirmed by the optical microscopy technique and critical micelle concentration measurement. The notable advantages of the present protocol were simple work-up procedure, high yield within short reaction time, easy separation of products, avoiding tedious column chromatography thus making the protocol environmentally friendly, sustainable, and economical. [ABSTRACT FROM AUTHOR]

The prime objective of this study is to estimate the natural radioactivity and their associated radiological hazards in soil samples of Uttara Kannada district having different geological conditions. The 226Ra, 232Th and 40K activities were estimated using HPGe detector based gamma ray spectrometer. The average 226Ra, 232Th and 40K activity concentrations are 36.13 ± 0.96, 48.47 ± 1.26 and 415.76 ± 6.83 Bq kg−1 respectively. The mean annual effective dose equivalent value was found to be 0.40 mSv y−1 and is less than the ICRP proposed value of 1 mSv y−1. The radiological hazard indices were computed and compared with internationally agreed values. [ABSTRACT FROM AUTHOR]

The 226Ra, 232Th and 40K activities were investigated in soil samples of Chikkamagaluru district, Karnataka, using γ-ray spectrometry. The average activity of 226Ra, 232Th and 40K were found to vary from 15.2 ± 0.6 to 58 ± 1.2 Bq kg−1, 14 ± 0.6 to 86.2 ± 1.7 Bq kg−1, and 224.5 ± 5.5 to 1650 ± 20.3 Bq kg−1 with a mean value of 36.93 ± 1.0, 51.6 ± 1.3 and 566.97 ± 11.0 Bq kg−1. The average activity concentrations are slightly higher than world average value. The average annual effective dose is more than the Indian average value of 0.084 mSv y−1. The average values of all the radiological hazards are less than the criterion limit. [ABSTRACT FROM AUTHOR]

An experimental investigation was conducted to study the effect of relative waviness (amplitude-to-wavelength ratio) on heat transfer and pressure drop characteristics of wavy minichannel array heat sinks. Hydrodynamically fully developed flows of de-ionized (DI) water, and 0.5% and 0.8% concentrations of Al2O3/water nanofluid were introduced into two heat sinks, each with an array of 15 rectangular wavy minichannels of amplitude-to-wavelength ratio of 0.100 and 0.133. The minichannels had a width of 0.9 mm and a depth of 1.3 mm and were machined on a 30 × 30 mm2 Aluminum substrate of 11 mm thickness. Reynolds number was varied from 700 to 2300 and a constant heat flux of 45,000 W/m2 was applied. Analysis of experimental results suggests increases in both Nusselt number and pressure drop with an increase in relative waviness in the laminar and transitional flow regimes. A maximum performance factor (PF) of 2.6 is achieved for a Reynolds number of 1900 using DI water in the wavy minichannels of higher relative waviness. Temperature distributions and new Nusselt number correlations for both geometries are also presented. [ABSTRACT FROM AUTHOR]

A sustainable, green and efficient process for the synthesis of 2-nitro alcohol derivatives from different substituted aromatic aldehydes with nitroalkane by stirring at ambient temperature with high product yield is reported. Adoption of very mild reaction conditions, use of Calcined Eggshell (CES) as natural catalyst and simple workup are expected to contribute to the development of environmentally benign synthetic method for Henry (nitroaldol) reaction. CES is ecologically safe, inexpensive, and attractive heterogeneous base catalyst obtained from renewable resources, thus opening a new perspective for this process. [ABSTRACT FROM AUTHOR]

Bacterial diversity of four thermally different hot springs of Ratnagiri district, Maharashtra, India, was investigated using culture-dependent and culture-independent approaches. A total of 144 bacterial cultures were isolated and identified using MALDI-TOF MS (matrix-assisted laser desorption ionization-time of flight mass spectrometry) and 16S rRNA gene sequencing. Culture-independent analysis by Ion Torrent sequencing targeting the V3 region of the 16S rRNA gene revealed the predominance of Firmicutes across all the hot springs, followed by Chloroflexi, Bacteroidetes, Cyanobacteria, Proteobacteria, Armatimonadetes, Actinobacteria, Nitrospirae, Acidobacteria, and Deinococcus–Thermus, with subtle differences in their abundance. At the lower taxonomic rank of genus, we noted the prevalence of Acinetobacter followed by Clostridium, Planomicrobium, Bacillus, Streptomyces, and Leptolyngbya. Metagenomics imputation using in silico approach revealed divergence in the metabolic capabilities of bacterial communities along the thermal gradient of host springs, with site TS (63 °C) featuring the abundant functional gene families. [ABSTRACT FROM AUTHOR]