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Crystal structures of 1,7-bis(furyl)-4-(1,3-dithiolan-2-ylidene)-1, 6-heptadiene-3,5-dione and 1,7-bis(thienyl)-4-(1,3-dithiolan- 2-ylidene)-1,6-heptadiene-3,5-dione
The title compounds (bis(alkenoyl) ketene dithioacetals) were prepared starting from the cyclic acyl ketene dithioacetal and aromatic aldehydes. These compounds were characterized by IR, 1H NMR, mass spectral studies and X-ray crystal structure analysis. The bis(furyl) ketene dithioacetal crystallized in the space group P1? with unit cell dimensions a = 7.7626(12) , b = 9.0217(13) , c = 26.827(5) , ? = 86.271(14), ? = 87.643(14), ? = 66.286(11) and the structure was refined to an R-factor of 0.0528 while bis(thienyl) ketene dithioacetal crystallized in the space group P21/c with unit cell dimensions a = 10.2433(9) , b = 10.4142(6) , c = 18.0973(18) , ? = 106.0 and the structure was refined to an R-factor of 0.0446. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in these compounds. In both the crystal structures, the crystal packing is stabilized by C-H?O hydrogen bonds as well as van der Waals interactions. Springer Science+Business Media, LLC 2011. -
Three decades of advances in extraction and analytical techniques for guava (Psidium guajava L.): A review
Despite extensive experimental focus, there remains a notable gap in comprehending the progressive development of these techniques over time. This comprehensive review is dedicated to cataloging the evolution of extraction and analytical methods spanning several decades. In this article, we meticulously traced the development of analytical and extraction techniques. Additionally, we intricately map the periodic discovery of metabolites within guava fruit, aligning them with the chronological utilization of analytical methods. This article results from extensive research and literature analysis to bridge the knowledge gap. Our efforts highlight the advantageous phytochemicals in guava and the diverse extraction techniques available. By encompassing various facets of analytical methods and delving into metabolomics, this review can offer substantial benefits to cultivating future guava varieties. Subsequent sections within this review will serve as a valuable resource, aiding prospective researchers in identifying the most effective extraction and analytical methods for discovering novel metabolites in guava or similar biological samples. Furthermore, through a comprehensive timeline detailing methodological advancements, this review enhances our understanding of the evolutionary path of guava research. Such insights empower researchers to make informed decisions and actively contribute to the continual advancement of the field of research. 2024 -
A statistical approach to study anatomical changes of pink guava cultivar (Psidium guajava L. cv Arka Kiran) during its ripening at the room temperature storage
The ripening of climacteric fruit like guava is a complex process that is highly coordinated with its cellular backbone. In the present study, we combined microscopy, spectrophotometry, and statistical analysis to evaluate the anatomical changes in the pink variety of guava during five ripening stages (pre-ripe, ripe, color-turn, half over-ripe, and over-ripe) during its storage at room temperature (282 C). The cholorophyll content of the peel, as determined by the measurement of chlorophyll a, b, and total chlorophyll, showed a significant decrease during the maturation process (4.05, 4.53, and 8.62 ?g/cm2, respectively, in the pre-ripe stage to not detectable in the over-ripe stage). Gradual loss of integrity of the fruit pulp (pericarp) from the preserved bee-hive structure to cell mass was also monitored by studying the cellular anatomy with brightfield and scanning electron microscopy. The epidermal thickness and width of the cortical parenchyma cells revealed statistical differences from the initial pre-ripe stage to the final full-ripe stage. Finally, based on the cellular dimensions, multivariate analysis using PCA (Principal Component Analysis) tool grouped the stages into three clusters, namely, pre-ripe: ripe, color-turn: half-over ripe, and over-ripe stages. In conclusion, this study provided significant insights into cultivar-specific anatomical changes in guava fruit, with potential for future research to develop variants with longer post-harvest storage life. 2024 The Author(s) -
Unravelling Post-harvest Ripening Metabolomics of a New White Variety Guava Fruit (Cv Arka Mridula) with Special Emphasis on Phenolics and Corresponding Antioxidants
The phenolic, antioxidant and metabolic profiling of a new white variety guava fruit Arka Mridula (AM) was performed during its storage at theroom temperature (28 2 C). The comparative profiles were generated at three ripening stages (pre-ripe, ripe and over-ripe) of the fruit. Generally, a steady decrease of the phenolic and antioxidant content from the pre-ripe to the ripe stage and a subsequent increase from the ripe to over-ripe stage was observed. Further, a powerful correlation between the phenolic content and antioxidant principles was noted through the principal component analysis. We could identify 53 compounds for the hydro-methanolic fruit extract through LC and GC-MS aided metabolic analysis, and the identified compounds were dominated by phenolics (~ 44%). The statistical analysis revealed that phytochemicals catechin, myricitrin, myricetin, kaempferol glycosides and n-hexadecanoic acid contributed significantly towards the ripening process of AM, during the storage. The present study is expected to provide important insight into the ripening biochemistry of AM. Subsequently, it may help in the future development of metabolically stable guava cultivars with extended post-harvest shelf life. Graphical Abstract: (Figure presented.) The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
Evaluation of phenolic and antioxidant profiles of pink Guava peel (Psidium guajava L. cv Arka kiran) during fruit ripening and its in silico Anti SARS-CoV-2 property
Guava (Psidium guajava L.) is a highly nutritious and economically important fruit. Although fruit peel is generally regarded as a waste, researchers believe that the peel of the guava is rich in bioactive constituents, even higher than the fruit's flesh. The present study aimed to estimate phenolic content (total phenolic and total flavonoid) and assess antioxidant properties of guava fruit peel (pink variety, cv Arka kiran) by 2,2-di (4-tert-octylphenyl)-1-picryl-hydrazyl (DPPH), 2,2?-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and Ferric Reducing Antioxidant Potential (FRAP) assays at five different ripening stages (stage 1 to 5). The TPC and TFC assays were performed by Folin-Ciocalteu and aluminium chloride (AlCl3) methods, respectively. The molecular docking experiment between the major phenolic of guava peel, Catechin and the spike protein of SARS-CoV-2 was performed by the Dockthor online server. Results showed that the peel had high phenolic (highest TPC and TFC, 7307.3 mg gallic acid equivalent/g dry weight [DW] and 433.9 mg quercetin equivalent/g DW, respectively) and antioxidant values (highest DPPH, ABTS and FRAP values 4784.8, 206.6 and 2451 mg ascorbic acid equivalent/g DW, respectively) throughout all stages, although there was a gradual decline in the activity at the later stages. Furthermore, it was found that catechin had a strong binding affinity (-7.591 kcal mol-1) with the spike protein, in silico when compared with the control drug ceftazidime (-7.250 kcal mol-1). The overall outcome of our experiemnts revealed that guava peel could be explored for future pharmacological applications through in vivo studies, and the green mixed with the yellow stage of ripening is optimum for such studies. Author (s). -
Synthesis and electrochemical studies of 1,1-binaphthyl-2,2-diol for aqueous rechargeable lithium-ion battery applications
The constant increase in the utilization of lithium-ion batteries (LIBs) in various field applications, including electrical vehicles and electronic devices, has led researchers to focus on their multiple path developments to obtain new electrode materials. The practical development of these electrode materials, based on organic and inorganic moieties, is challenging for various groups of LIB scientists. The concept of organic electrode materials is highly competitive with inorganic electrode materials because of the accessibility of more active sites with structural diversity, high energy and power density, environmental friendliness potential sustainability, and low cost. Herein, 1,1-binaphthyl-2,2-diol (BINOL) is investigated as an organic electrode material that contains two hydroxyl groups that act as active centers. The oxidative coupling process is employed to synthesize BINOL and so obtained product was characterized by using FT-IR, 1H-NMR and MASS techniques. The electrochemical investigations were carried out using sat. Li2SO4 electrolytic medium at three-electrode cell system. The Cyclic voltammetry (CV) has provided information on the anodic behavior of the material and its stability studied at different scan rates. The battery performance of the cell BINOL | Sat. Li2SO4 | LiMn2O4 by galvanostatic charge-discharge potential limit (GCPL) shows 197/171mAhg?1 specific capacity and 90% columbic efficiency. The electrochemical kinetic obtained by potentiostatic electrochemical impedance spectroscopy (PEIS) shows a semi-infinite diffusion process. 2024 Elsevier B.V. -
Injective edge coloring of graphs
Three edges e1, e2 and e3 in a graph G are consecutive if they form a path (in this order) or a cycle of lengths three. An injective edge coloring of a graph G = (V, E) is a coloring c of the edges of G such that if e1, e2 and e3 are consecutive edges in G, then c(e1) ? c(e3). The injective edge coloring number ?? i (G) is the minimum number of colors permitted in such a coloring. In this paper, exact values of ?? i(G) for several classes of graphs are obtained, upper and lower bounds for ?? i (G) are introduced and it is proven that checking whether ?? i (G) = k is NP-complete. 2019, University of Nis. All rights reserved. -
Relevance for demographic factor: Level of financial literacy
The study assesses the level of Financial Literacy of residents of Puducherry and investigates the impact of demographic characteristics on their Financial Literacy. A total of 637 residents residing in seven different blocks of Puducherry constituted the sample of the study. Multinomial regression model was used to see the impact of demographic variables on the levels of Financial Literacy. The results indicated that the level of Financial Literacy was affected by factors including gender, marital status, work status, level of education and number of financial dependents in a family. These statistically significant results suggested that male respondents who are married and have 3 financial dependents having self employment or salaried job living in rural areas tend to have high level of financial literacy. 2018 SCMS Group of Educational Institutions. All rights reserved. -
Automatic Measurement and Differentiation of Traffic Volume Count
Traffic volume in India is growing drastically over the past few decades. This leads to an increased need of constructing more highways and underpasses. In order to have the definite knowledge of traffic volume, and to design the width and thickness of the pavements, periodical conduction of traffic census is necessary. At present, the evaluation of traffic volume is conducted manually. This system is tiresome and lacks accuracy. The data obtained from the traffic census decides the sanction of new highways, underpasses, or flyovers which involves huge investments. Hence, the accuracy of this data is very critical. In this paper, we propose an automatic tool that helps to measure the traffic volume and differentiate the vehicles using video processing tools in MATLAB. The proposed algorithm consists of the following steps: i Foreground Detection ii Blob Detection iii Blob Analysis iv Vehicle differentiation Counting. 2018 IEEE. -
Securing Automated Systems with BT: Opportunities and Challenges
The use of automated systems is becoming increasingly prevalent in various industries; however, they pose significant security risks. In order to enhance the security of these systems, Blockchain Technology (BT) provides a promising solution. This chapter discusses the opportunities and challenges associated with using BT to secure automated systems. The role of BT in securing automated systems is discussed, emphasizing its ability to improve security and transparency. Additionally, BT-based systems with enhanced security are examined, such as decentralized data management, immutable and transparent ledgers, reduced cyber-attacks, and secure data sharing. Despite these opportunities, challenges such as high computational power requirements, integration challenges, BT scalability, and regulatory challenges must be addressed. Utilizing BT can create a more secure and transparent system that can help to prevent fraud, hacking, and other forms of cyber-attacks, ultimately enhancing the reliability and safety of automated systems. In conclusion, this paper highlights the potential of using BT for securing automated systems and the need for continued research and development to overcome the challenges associated with its implementation. 2024 selection and editorial matter, Nidhi Sindhwani, Rohit Anand, A. Shaji George and Digvijay Pandey; individual chapters, the contributors. -
Psychological experiences and travel Adversities: A Mixed-Method study of the regular commuters in traffic congestion
This study investigated the psychological experiences and consequences of travel adversities during traffic congestion using a three-phase sequential exploratory mixed-methods design. Phase 1 explored the travel adversities, psychological experiences, and consequences of a sample of ten (four women and six men) regular commuters of Bangalore's congested roads using semi-structured interviews. In phase 2, a checklist was developed listing the fundamental themes from phase 1 with Likert-type responses ranging from 0 (never) to 5 (always). Phase 3 gathered data in the checklist and tested the statistical validity of the thematic model in a sample of 190 (81 women and 103 men) regular commuters. Attride-Stirling model thematic network was established with 57 fundamental themes categorized and assigned under the organizing themes of travel adversities (n = 6), negative affect (n = 28), fight (n = 7), flight (n = 6), and negative road occurrences (n = 10), in the global theme, psychological experiences and consequences. Structural equation modeling indicated that (1) negative affect significantly predicted fight and flight, (2) fight is a significant predictor of negative road occurrences, and (3) psychological experiences and consequences create a self-perpetuating cycle, with travel adversity triggering negative emotions, which results in fight responses leading to negative road occurrences, further intensifying travel adversity. A mathematical model is established based on this statistical validation, which holds potential applications in real-time traffic algorithms. 2024 -
Bioinformatics applications for evaluating health and pharmacological properties of tea: Use of computer-assisted drug discovery tools
Bioinformatics has emerged as a crucial tool in tea research, enabling the exploration of the genetic and molecular intricacies underlying tea cultivation, quality, and health benefits. By leveraging bioinformatics, researchers have extensively explored, inferred, and evaluated the pharmacological properties of tea. This groundbreaking approach has unveiled a myriad of possibilities for utilizing the bioactive compounds present in tea. Metabolomics studies have unraveled the intricate metabolic pathways within tea plants, providing insights into the synthesis and accumulation of bioactive compounds. Bioinformatics in tea research opens new avenues for the tea industry, benefiting both producers and consumers worldwide. These advancements not only deepen our understanding of tea biology but also hold immense potential for sustainable tea production, the discovery of novel bioactive compounds, and the optimization of tea flavors and health benefits. This chapter explains the bioinformatic tools used to identify various therapeutic properties of tea biocompounds. 2025 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies. -
Multivariate statistical optimization of phenolics and antioxidants from nutmeg seeds (Myristica fragrans Houtt)
The present study aimed to optimize the phenolic and antioxidant-rich extract from the nutmeg (Myristica fragrans Houtt) by using a two-factor 26-run central composite design-based response surface methodology tool. The selected parameters were extraction period (2 to 5days), solvent-to-water ratio (v/v) (50100%), and type of solvent (acetone or ethanol). The optimized extract at conditions of 3.14days incubation and 68% (v/v) acetone showed total phenolic content (TPC), total flavonoid content (TFC), and DPPH antioxidant assay as 376.38mg GAE/g DW, 34.40mg QUE/g DW and 842.46mg AAE/g DW, respectively. Among the nineteen (19) compounds identified by the LCMS, myristicin (37.74%) was found to be the highest. Nine (9) alkane-fatty acyl compounds were determined by the GCMS analysis, as well. Additionally, SEM and XRD revealed sheet-like anatomy with the presence of Carbon (C), Oxygen (O) and Potassium (K). The study presented a unique approach to optimizing phenolic-rich antioxidant extracts from nutmeg using response surface methodology, offering valuable insights for more efficient extraction of bioactive compounds with minimal resource waste and potentially enhancing the utilization of nutmeg's nutraceutical properties. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024. -
On the zero forcing number of graphs and their splitting graphs
In [10], the notion of the splitting graph of a graph was introduced. In this paper we compute the zero forcing number of the splitting graph of a graph and also obtain some bounds besides finding the exact value of this parameter. We prove for any connected graph ? of order n ? 2, Z[S(?)] ? 2Z(?) and also obtain many classes of graph in which Z[S(?)] = 2Z(?). Further, we show some classes of graphs in which Z[S(?)] < 2Z(?). Journal Algebra and Discrete Mathematics. -
Disproportionate impact of climate change: Housing crisis and displacement among the transgender community in India
India is a nation that is threatened by climate change. Climate change and the housing crisis are inextricably linked, they are associated with exacerbated mental and physical health conditions. It often affects individuals differently based on various factors shaped by social norms. So, marginalized sections like transgender persons are disproportionately affected. Individuals with inadequate housing are significantly affected by natural disasters. However, most transgender individuals cannot rent due to a lack of documents and unemployment. Thus, housing is an essential social determinant of physical and mental health. The book chapter discusses the various intersecting identities and the geographical and ecological contexts. The current revised climate laws in India have emphasized incorporating gender but there is a need to focus on gender beyond the binary to formulate more sensitive and equitable methods to address climate change. It also discusses the psycho-social impact on the community and the unique challenges they face as extreme weather events increase. 2024, IGI Global. All rights reserved. -
Semantic image annotation using convolutional neural network and WordNet ontology
Images are a major source of content on the web. The increase in mobile phones and digital cameras have led to huge amount of non-textual data being generated which is mostly images. Accurate annotation is critical for efficient image search and retrieval. Semantic image annotation refers to adding meaningful meta-data to an image which can be used to infer additional knowledge from an image. It enables users to perform complex queries and retrieve accurate image results. This paper proposes an image annotation technique that uses deep learning and semantic labeling. A convolutional neural network is used to classify images and the predicted class labels are mapped to semantic concepts. The results shows that combining semantic class labeling with image classification can help in polishing the results and finding common concepts and themes. 2018 Jaison Saji Chacko, Tulasi B. -
MoS2-TiO2 Nanocomposites for Enhanced Photo-electrocatalytic Hydrogen Evolution
The investigation on the designing and fabrication of highly efficient electrocatalysts for hydrogen evolution reaction (HER) is critical for future applications in renewable sustainable energy. The present work reports the hydrothermal synthesis of two-dimensional MoS2 and MoS2-TiO2 nanostructures. The as-prepared nanostructures were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Raman analysis, UV-vis-NIR, and photoluminescence spectrophotometry and vibrating sample magnetometer (VSM). Systematic electrochemical measurements for HER were performed and MoS2-TiO2 nanocomposites demonstrated the lowest onset potential in comparison with MoS2. The results suggest that the nanofusion interface between MoS2 nanoflakes and TiO2 nanoparticles induced an efficient charge transfer from the conduction band of MoS2 to TiO2 and favored the reduction of H+ at active sites. We believe the present work can open up new possibilities that would provide deep insights for the rational design of 2D materials-based catalysts for energy storage and conversion applications. 2023 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. -
Synthesis, Structure, and Physical Properties of Bulk MoS2
With the discovery of graphene by Novoselov and Geim in 2004, two-dimensional (2D) materials have been extensively researched due to their bizarre promise in the fields of electronics, optics, medical, mechanics, energy conversion, and storage. Especially, 2D-layered materials consisting of atomic sheets stacked together by weak van der Waal forces have received intriguing research interest in recent years. Cutting-edge 2D materials being investigated by researchers include 2D oxides (V2O5, MoO3, LixCoO2), topological insulators (Bi2Se3, Bi2Te3, HfBr), nitrides (h-BN, MoN, Ti4N3Tx, W2N, V2N), carbides (Ti3C2, Ta4AlC3), and transition-metal dichalcogenides (MoS2, WS2). Research has proved that these materials could counterpart graphene in a variety of fields and applications. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Recent development on self-powered and portable electrochemical sensors: 2D materials perspective
Electrochemical sensors have attracted tremendous research interest due to their simplicity and compatibility to be integrated with standard electronic technologies and capability to produce electrical signals that can be effectively acquired, processed, stored, and analyzed. Due to the incredible electronic and physical properties derived from the 2D structure, two dimensional (2D) nanomaterials such as graphene, phosphorene black phosphorus, transition metal dichalcogenides (TMDCs), and others have proven to be attractive for the fabrication of high-performance electrochemical sensors. The book chapter is focused in the unique characteristics of 2D materials leading toward excellent sensing performance, the structural and molecular designing of various 2D materials, structure-property relationships, various sensing applications employing disparate 2D nanostructures with an emphasis on highlighting various prototypical and prominent research paths. 2023 Elsevier Inc. All rights reserved. -
MoS2, a new perspective beyond graphene
Owing to the fascinating structural, optical, electrical, chemical properties, graphene has created new paradigm in the field of nanoscience and the common crystalline structures that can be exfoliated include the layered van der Waals (vdW) solids such as boron nitride, transition metal dichalcogenides (TMDCs), black phosphorus, and the layered ionic solids. Here, we bring forth the state-of-art-of materials dominated by their two-dimensional (2D) geometry beyond graphene. Being one of the most well-studied families of vdW layered materials, molybdenum disulphide (MoS2) belonging to TMDC family has gained considerable research interest. The present work is focused on attempts to optimize and characterize this material with unique properties for a host of applications. The work resolves the hydrothermal growth of hexagonal MoS2 nanoflakes with attracting optical and magnetic properties providing strong evidence for the spin orbit split valence bands of these nanostructures. The enhanced electrocatalytic activity, excitation wavelength dependent down-conversion and up-conversion photoluminescence, growth of structural polymorphs using simple hydrothermal method, and the efficient anticancer properties of MoS2 nanostructures providing greater insight into energy and biomedical applications are also discussed. The improved catalytic activity of MoS2-based nanostructures reveals the increasing number of accessible active sites, formation of large surface area and is greatly beneficial for accomplishing a clean, environmental-friendly, inexpensive hydrogen mission for energy storage and conversion applications. The synergistic effect of the MoS2 nanocomposites was able to impede angiogenesis, tumor growth, and epithelial to mesenchymal transition, elucidating the anticancer efficacy. Understanding and exploiting such unique properties of these 2D materials paves new horizons toward novel technological advances in electronic and medical field. 2021 Elsevier Inc. All rights reserved.