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Synthetic Applications of Prins Cyclization in Natural Product Syntheses
The natural products having tetrahydropyran unit with multiple chiral centers serve as magnificent building blocks for various active pharmaceutical ingredients (APIs). Prins cyclization is one of the wonderful strategies to construct tetrahydropyran unit stereoselectively in asymmetric synthesis. In this account, we discuss our research efforts toward the synthesis of various natural products from the past two decades (20052020) by using Prins cyclization as a key step. Further, the synthetic utility of this reaction was investigated and well demonstrated on various molecules successfully. 2022 The Chemical Society of Japan & Wiley-VCH GmbH. -
A catalytic, one-pot and green synthesis of α-amino nitriles : Cu(BF4)2.X H2O an efficient catalyst /
Letters In Organic Chemistry, Vol.14, Issue 6, pp.440 - 445, ISSN: 1570-1786. -
Lipase-Catalyzed Resolution Of 1-[4-(Benzyloxy)phenyl]hex-5-en-3-ol: Synthesis of (-)-Centrolobine /
Asian Journal Of Chemistry, Vol.29, Issue 10, pp.2321-2326, ISSN: 0975-427X (Online) 0970-7077 (Print). -
Classification of Psychological Disorders by Feature Ranking and Fusion using Gradient Boosting Classification of Psychological Disorders
Negative emotional regulation is a defining element of psychological disorders. Our goal was to create a machine-learning model to classify psychological disorders based on negative emotions. EEG brainwave dataset displaying positive, negative, and neutral emotions. However, negative emotions are responsible for psychological health. In this paper, research focused solely on negative emotional state characteristics for which the divide-and-conquer approach has been applied to the feature extraction process. Features are grouped into four equal subsets and feature selection has been done for each subset by feature ranking approach based on their feature importance determined by the Random Forest-Recursive Feature Elimination with Cross-validation (RF-RFECV) method. After feature ranking, the fusion of the feature subset is employed to obtain a new potential dataset. 10-fold cross-validation is performed with a grid search created using a set of predetermined model parameters that are important to achieving the greatest possible accuracy. Experimental results demonstrated that the proposed model has achieved 97.71% accuracy in predicting psychological disorders 2023, International Journal of Advanced Computer Science and Applications.All Rights Reserved. -
Multi-layer Stacking-based Emotion Recognition using Data Fusion Strategy
Electroencephalography (EEG), or brain waves, is a commonly utilized bio signal in emotion detection because it has been discovered that the data recorded from the brain seems to have a connection between motions and physiological effects. This paper is based on the feature selection strategy by using the data fusion technique from the same source of EEG Brainwave Dataset for Classification. The multi-layer Stacking Classifier with two different layers of machine learning techniques was introduced in this approach to concurrently learn the feature and distinguish the emotion of pure EEG signals states in positive, neutral and negative states. First layer of stacking includes the support vector classifier and Random Forest, and the second layer of stacking includes multilayer perceptron and Nu-support vector classifiers. Features are selected based on a Linear Regression based correlation coefficient (LR-CC) score with a different range like n1, n2,n3,n4 a, for d1 used n1 and n2 dataset,for d2 dataset, combined dataset of n3 and n4 are used and developed a new dataset d3 which is the combination of d1 and d2 by using the feature selection strategy which results in 997 features out of 2548 features of the EEG Brainwave dataset with a classification accuracy of emotion recognition 98.75%, which is comparable to many state-of-the-art techniques. It has been established some scientific groundwork for using data fusion strategy in emotion recognition. 2022. International Journal of Advanced Computer Science and Applications. All Rights Reserved. -
PEDOT-Doped Mesoporous Nanocarbon Electrodes for High Capacitive Aqueous Symmetric Supercapacitors
Poly(3,4-ethylenedioxythiophene) (PEDOT) and PEDOT-functionalized carbon nanoparticles (f-CNPs) were synthesized by in situ chemical oxidative polymerization and pyrolysis methods. f-CNP-PEDOT nanocomposites were prepared by varying the concentration of PEDOT from 1 to 20% by weight (i.e., 1, 2.5, 5, 10, and 20 wt%). Several characterization techniques, such as field-emission scanning electron microscopy (FESEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), N2 BrunauerEmmettTeller (BET) and BarrettJoynerHalenda (BJH) analyses, as well as cyclic voltammetry (CV), galvanostatic charge discharge (GCD), and electrochemical impedance spectroscopy (EIS), were applied to investigate the morphology, the crystalline structure, the N2 adsorption/desorption capability, as well as the electrochemical properties of these new synthesized nanocomposite materials. FESEM analysis showed that these nanocomposites have defined porous structures, and BET surface area analysis showed that the standalone f-CNP exhibited the largest surface area of 801.6 m2/g, whereas the f-CNP-PEDOT with 20 wt% exhibited the smallest surface area of 116 m2/g. The BJH method showed that the nanocomposites were predominantly mesoporous. CV, GCD, and EIS measurements showed that f-CNP functionalized with 5 wt% PEDOT had a higher capacitive performance compared to the individual f-CNPs and PEDOT constituents, exhibiting an extraordinary specific capacitance of 258.7 F/g, at a current density of 0.25 A/g, due to the combined advantage of enhanced electrochemical activity induced by PEDOT doping, and highly developed porosity of f-CNPs. Symmetric aqueous supercapacitor devices were fabricated using the optimized f-CNP-PEDOT doped with 5 wt% of PEDOT as active material, exhibiting a high capacitance of 96.7 F/g at 1.4 V, holding practically their full charge, after 10,000 chargedischarge cycles at 2 A/g, thus providing the highest electrical electrodes performance. Hereafter, this work paves the way for the potential use of f-CNP-PEDOT nanocomposites in the development of high-energy-density supercapacitors. 2024 by the authors. -
Functional carbon nanoparticles modified poly(3,4-ethylenedioxythiophene) nanocomposites with enhanced dielectric and antibacterial properties
The importance of nanocomposites with tailored properties is growing due to their applications in various fields. In the present study, poly(3,4-ethylenedioxythiophene) (PEDOT) and functionalized carbon nanoparticles (f-CNPs) are synthesized by in-situ chemical oxidative polymerization and pyrolysis methods, respectively. The f-CNPs-PEDOT nanocomposites are prepared by varying the concentration of PEDOT (i.e., 1, 2.5, 5, 10, and 20 wt%), and the thermal stability, dielectric properties and antibacterial activities of f-CNPs-PEDOT nanocomposites were evaluated. The dielectric studies indicated that the addition of PEDOT has enhanced the dielectric properties due to interfacial polarization effect, whereas decreased the thermal stability due to degradation of PEDOT in the nanocomposite, however, it is higher than the pure PEDOT. The antimicrobial potential of synthesized f-CNPs-PEDOT nanocomposites was studied against two different bacterial strains, namely Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The findings of this research have potential to open new opportunities for employing f-CNPs-PEDOT nanocomposites in physical sciences and antimicrobial applications. 2024 The Authors -
White Light Emission from Dy3+-Activated CaY2O4 Phosphor
Synthesis and characterization of a Dy3+-activated calcium yttrium oxide (CaY2O4) phosphor are reported. The CaY2O4:Dy3+ (1.5 mol%) phosphor is synthesized using a modified solid-state reaction technique for calcination and sintering. The cubic structure is revealed by the X-ray diffraction technique. The morphology and particle size distribution of the prepared phosphor are investigated by the FEGSEM technique. The chemical bonds and functional group analysis are confirmed by the FTIR. A photoluminescence analysis of the CaY2O4:Dy3+ phosphor shows dual excitation wavelengths at 285 and 348 nm, especially in the ultraviolet region. At 383 nm, three distinct emission peaks are found at the wavelengths 238, 485, and 571 nm. The spectroscopic parameters are calculated using the CIE chromaticity coordinates. The CIE coordinates of the Dysprosium ion-activated CaY2O4 phosphor (1.5 mol%) show an emission near the white light region of the chromaticity diagram, suggesting that it is suitable for W-LED applications. The Author(s), under exclusive licence to Springer Nature Switzlerland AG 2024. -
Prevalence and predictors of diabetes among adults in rural Dharwad, India: A cross-sectional study
Objective: Diabetes is a long life chronic non-communicable disease and emerging fast as one of the most serious health problems in developed and developing countries, also influences the risk of developing macrovascular complication including heart disease and stroke which are the leading causes of global death. This study aims to find the potential risk factors associated to diabetes among different community (Government, Private employees, and Businessmen) of adults 20 years and above. Methods: A cross-sectional study followed and conducted door-to-door survey using World Health Organization STEP Surveillance (WHO STEPS) questionnaire to collect the information of sociodemographic, anthropometric and behavioral characteristics. Multiple logistic regression is used to determine the risk factors of diabetes among study population. Data was pre-processed and used Chi-square test and t-test to find the comparison between the attributes. Results: Overall prevalence of diabetes is found to be 49.1% in which prevalence more in females with 51.7% than in males with 46.8%, the education, health examination, and waist circumference were found to be the potential risk factors. The total study subjects include 1083 in which male is 611 and female is 472. Conclusion: The current study reflects the importance of Diabetes disease among the study population in rural Dharwad and this study can be utilized to control and prevent diabetes. Its an early call for the females of the study population to take care and practice healthy food in day today life and the outcome of the study says that the education should be given prime importance in everyones life. 2018 The Authors. -
Review of Development and Characterisation of Shape Memory Polymer Composites Fabricated Using Additive Manufacturing Technology
Structures as well as components are generated by depositing filaments on one another via the technique of additive manufacturing. Among the various processes of printing, 4D printing combines the technology of 3D printing with the passage of time, resulting in additively generated parts that are responsive to stimuli from the outside via modifications of their form, volume, size, or mechanical qualities. Thus, the materials of shape memory are used in 4D printing and respond to environmental factors including temperature, pH, and humidity. Shape memory polymers (SMPs) are materials with a shape memory effect that are best suited for additive manufacturing. Contrarily, the method named fused filament fabrication (FFF) is employed most frequently among all additive manufacturing methods. In this regard, the objective of the present study is to evaluate all investigations that have been conducted on 4D-FFF materials mechanical properties. The study offers an unparalleled overview that highlights the possibilities of 4D FFF printing across multiple applications in engineering while keeping the end structures or components structural integrity in consideration. 2023 by the authors. -
Thermal behavior of PC-ABS based graphene filled polymer nanocomposite synthesized by FDM process
Property enhancement of polymers could be achieved through blending of two or more polymers and via addition of filler materials to meet the application requirements. In the present investigation Polycarbonate (PC) and Acrylonitrile Butadiene Styrene (ABS), the two polymers were blended together and Graphene platelets as nanofiller was added in the ratio of 0.2, 0.4, 0.6 and 0.8 wt% respectively. Polymer blend and graphene platelets were mixed at appropriate temperature and extruded out in the form of filament of 1.75 mm diameter. Filament was used as a feed material for Fused Deposition Modelling (FDM) to develop the test samples. The nanocomposites developed using FDM were subjected to differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) to study the effect of graphene platelets. Addition of graphene platelets resulted in significant increase in Young's modulus with highest value of 4.038 GPa obtained for nanocomposite with 0.8% graphene content. Thermal analysis showed that addition of graphene platelets increases the glass transition temperature and reduces the mass with increase in temperature. 2019 -
Synthesis and characterization of flyash reinforced polymer composites developed by Fused Filament Fabrication
Fused filament fabrication (FFF) has seen an upsurge in its utilization towards development of tailored made materials of polymer base. The advancement and diversity in fabricating the polymer composite parts by using FFF has seen the embracement of this technology in wider aspects, ranging from automotive, aerospace, construction and has marched towards day to day requirements. This research article focuses on development of polymer composite; by using flyash (FA), an industrial waste produced during coal combustion, as reinforcement in Acrylonitrile butadiene styrene (ABS) matrix, to study the physical and mechanical properties. FA, which is primarily made up of metal oxides, plays an imperative role as reinforcement. Easily and abundantly available, FA is being used in several applications to reduce the landfills utilization and also helps the environment. In this study FA was added as reinforcement in 5 and 10 wt. % respectively to ABS matrix and was developed into filament of 1.75 mm diameter. The developed ABS + FA polymer composite using FFF, were analyzed for physical and mechanical properties as per American Society for Testing and Materials (ASTM) standards. Microstructure studies were carried out for the developed composite to understand their behavior in enhancing the dimensional accuracy and tensile strength with incremental addition of FA up to 10 wt%. Tensile strength was enhanced by 28.19% and 36.13% for ABS + 5wt. % FA and ABS + 10wt. % FA respectively. Dimensional stability was also enhanced. Similarly, surface roughness analysis was carried out and it was observed to reduce with addition of FA. The surface roughness measurements provided suitable results of decrement by 9.64% and 14.6% for ABS + 5wt. % FA and ABS + 10wt. % FA respectively. Overall, the usage of FA along with FFF, has paved a path in sustainable and green technology in manufacturing. 2022 The Author(s). -
Social Network User Profiling With Multilayer Semantic Modeling Using Ego Network
Social and information networks undermine the real relationship between the individuals (ego) and the friends (alters) they are connected with on social media. The structure of individual network is highlighted by the ego network. Egocentric approach is popular due to its focus on individuals, groups, or communities. Size, structure, and composition directly impact the ego networks. Moreover, analysis includes strength of ego alter ties degree and strength of ties. Degree gives the first overview of network. Social support in the network is explored with the gap between the degree and average strength. These outcomes firmly propose that, regardless of whether the approaches to convey and to keep up social connections are evolving because of the dispersion of online social networks, the way individuals sort out their social connections appears to remain unaltered. As online social networks evolve, they help in receiving more diverse information. 2022 IGI Global. All rights reserved. -
Hybrid shuffled frog leaping and improved biogeography-based optimization algorithm for energy stability and network lifetime maximization in wireless sensor networks
Wireless sensor networks are significantly used for data sensing and aggregating dusts from a remote area environment in order to utilize them in a diversified number of engineering applications. The data transfer among the sensor nodes is attained through the inclusion of energy efficient routing protocols. These energy efficient routing necessitates optimal cluster head selection procedure for handling the challenge of energy consumption to extend the stability and lifetime in the sensor networks. The implementation of energy efficient routing is still complicated even when the process of clustering is enhanced through the cluster head selection. The majority of the existing cluster head selection schemes suffer from the issues of poor selection accuracy, increased computation, and duplicate nodes' selection. In this paper, hybrid shuffled frog leaping and improved biogeography-based optimization algorithm (HSFLBOA) for optimal cluster head selection is proposed for resolving issues that are common in cluster head selection schemes. This proposed HSFLBOA used the objective function that used the parameters of node energy, data packet transmission delay, cluster traffic density, and internode distance in the cluster. The simulation results of the proposed HSFLBOA is determined to be significant in achieving superior throughput and network energy compared to benchmarked metaheuristic optimal cluster head schemes. 2021 John Wiley & Sons Ltd. -
The challenge of gender stereotyping in Indian courts
Womens negotiations towards achieving justice are elusive due to patriarchal, cultural and caste norms. The expectation of compromise permeates Courts, even in rape cases. In spite of the prevalence of well-formulated substantive and procedural aspects of law, the constitutional promise of equality is still a distant dream for women. Intersectional factors like tradition, caste, religion and cultureall act as impediments to securing justice for women in India. In fact, gender bias plagues the criminal justice administration. This paper relies on landmark cases to demonstrate the biases exhibited by Courts, in matters of sexual assault and rape. The paper will also rely on feminist ideas to highlight the need for the law to understand the deep-rooted historical and socio-political contexts from which issues related to gender originate. The paper concludes by giving suggestions as to how gender bias can be done away with, by Courts. Law has to act as a transformative instrument if gender justice has to be achieved. Lawyers and judges should not be carried away by personal biases and prejudices and need to be socially sensitive while handling cases of crimes against women. 2022 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license. -
Trap of Race to the Bottom? Evidence from Pollution Intensive Products Trade in India and China
This article compares China and India, the two biggest emerging market economies in the world, with respect to their trade in pollution-intensive industries and tries to discuss the policy environment supporting such growth. The analysis is carried out for 13 categories of pollution-intensive products based on the Standard International Trade Classification Revision 3 classification. Our analysis reveals significant growth in trade in these products in both countries, with a higher intra-industry trade and a significant correlation with environmental stringency. Between the two, India seems to be enjoying a better comparative advantage. Findings suggest a need for adopting cleaner production processes and a cautious approach towards industrial promotion. 2023 Institute of Chinese Studies, New Delhi. -
Trade in Pollution-intensive Products: Evidence from India
This article explains Indias trade from an environmental perspective. Besides explaining trends and patterns of trade in pollution-intensive products, we investigate Indias comparative advantage in these products and discuss the emerging issues. The exercise based on the UN Comtrade dataset reveals that much of Indias exports happen under this category with better revealed comparative advantage (RCA) values, which do have high environmental concerns. We sum up the article by arguing that there is a need to attend to sector-specific problems encountered by these industries and have a well-knit environmental policy, so that trade and industrial expansion do not have a major environmental concern. 2022 Management Development Institute. -
Performance evaluation and sustainability analysis of geopolymer concrete developed with ground granulated blast furnace slag and sugarcane bagasse ash
This experimental work aims to determine the workability, strength and sustainability aspects of geopolymer concrete developed with GGBS and SCBA in five different proportions of 100-0%, 95 ? 5%, 90 ? 10%, 85 ? 15%and 80 ? 20%. 8M NaOH concentration and Na2SiO3 solutions are used as an alkaline activator in mixes developed. Na2SiO3 to NaOH ratio of 2.5 and 0.5 alkaline liquid to binder ratio is employed in this study to develop ambient cured geopolymer concrete. The results show that the standard consistency and FST of geopolymer paste increases with an increase in the SCBA content of mixes developed. Cs, Sts and Fs decreased with an increase in the content of SCBA in geopolymer concrete mixes. The 28 days Cs of geopolymer concrete developed under ambient cured condition varied from 63.56 to 39.59MPa. Regression analysis was performed to find the correlation between Sts and Fs to Cs. This study aims to outline a unique technique of utilizing an agro industrial waste by product i.e., sugarcane bagasse ash which in turn reduces disposal problem to some extent. According to the test findings, Sugarcane bagasse ash up to 20% can be used as precursor to develop sustainable geopolymer concrete. Due to the high cost of chemicals and river sand the cost of geopolymer concrete developed is slightly higher than normal concrete. Also, as the percentage of SCBA increase in the geopolymer concrete the demand for energy is reduced. Additionally, incorporation of sugarcane bagasse ash will also reduce disposal problems and reduces CO2 emissions into the atmosphere. The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024. -
Review on Durability of Geopolymer Concrete Developed with Industrial and Agricultural Byproducts
High population growth has increased the requirement for infrastructure development tremendously. Building materials like ordinary portland cement which is the primary component in concrete is growing due to the increased demand for new infrastructure. Concrete is the world's second most consumed material. Special concrete called Geopolymer concrete (GPC), is grabbing the interest of researchers as substitute to ordinary portland cement concrete (OPCC). Manufacture of cement is highly energy intensive and leads to large quantity of CO2 emission to atmosphere which in turn leads to global warming. Thus, replacement of cement with geopolymer material minimises pollution in two ways: by lowering cement consumption and utilisation and by lowering CO2 emission. Various industrial and agricultural waste materials like fly ash, metakolin, ground granulated blast furnace slag, silica fume, rice husk ash, sugarcane bagasse ash etc. are abundantly available. These aluminosilicate sources have been widely employed to develop geopolymer concrete with high strength, thermal resistance, and durability. This article is a review of research on the durability aspects of geopolymer concrete, its most significant durability parameters like resistance to acid attack, sulphate attack, water absorption, porosity, sorptivity, rapid chloride penetration, wet and dry cycle have been reviewed to comprehend these vital issues. 2023 -
On thermal performance of spine fin in magnetized hybrid fluid rooted with Cu and MoS4 nanoparticles
This study examines the thermal performance of diverse profiles of spine fins with variable thermal conductivity. A hybrid nanofluid comprising Cu, and MoS4 with water as the base fluid, is modeled mathematically. Both the cylindrical and concave parabolic profiles are taken into account. The comparative outcomes are inferred from numerical and semi-analytical methods. The non-dimensional temperature profiles are analyzed graphically while considering the fin tip to be insulated, and the effects of various thermal parameters are also investigated. We have observed that the heat transfer rate shows an opposite trend toward convective-conduction and porosity parameter. The study also revealed that the concave parabolic profile emits more heat in comparison with the cylindrical profile. 2024 Author(s).