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Synthesis, characterization and biological activity studies on 6-p-dimethylaminophenyl-5,6-dihydrobenzoimidazo [1,2-c]quinazoline: Crystal structure of the title compound and comparative study with related derivatives
Reaction of o-aminophenylbenzimidazole with p-dimethylaminobenzaldehyde yielded 6-p-dimethylamin-ophenyl-5,6-dihydrobenzoimidazo[ 1,2-c]quinazoline, which was characterized by elemental analysis, IR, UV-Vis, 1H NMR, 13C NMR, mass spectral studies and X-ray crystal structure analysis. Studies on the antimicrobial activity of the compound revealed that it is active against fungus Yeast but not Bacillus subtilis. The compound crystallized in the space group P2 1/n with the unit cell parameters a = 10.652(2) b = 11.002(2) c = 15.753(2) ? = 109.29(2) and the structure was refined to an R-factor of 0.0479. The hydropyrimidine ring in the quinazoline moiety is in skew-boat conformation. The dimethylamino group attached to phenyl ring is in conjugation with it. The structure was stabilized by intermolecular C-H-N interactions. A few of the related quinazolines (6-p-hydroxyphenyl-5,6-dihydrobenzoimidazo [1,2-c]quinazoline; 6-phenyl-5,6-dihydrobenzoimidazo[1,2-c]quinazoline; 6-pyridyl-5,6- dihydrobenzoimidazo[1,2-c]quinazoline; 6-furyl-5,6-dihydrobenzoimidazo[1,2-c] quinazoline) were also examined for their biological activity, in addition to their characterization by IR, UV-Vis, JH and 13C NMR spectral studies along with structural comparison. Springer Science+Business Media, LLC 2011. -
Crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3-dithiolan-2-ylidene)-1, 6-heptadiene-3,5-dione
The synthesis and crystal structure of 1,7-bis(4-chlorophenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound is a curcuminoid analogue, configurationally symmetric about the C4-C5 atoms and also retains the two fold axis in the crystal phase. This compound crystallizes in the space group C2/c with unit cell parameters a = 19.203(1) b = 13.147(1) c = 8.801(1) ? = 112.99(1), with half a molecule in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The push-pull nature of the ketenedithioacetal functionality organizes the cinnamoyl groups parallel to each other. 2008 Springer Science+Business Media, LLC. -
Synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione
The synthesis and crystal structure of 1,7-bis(4-methoxyphenyl)-4-(1,3- dithiolan-2-ylidene)-1,6-heptadiene-3,5-dione is described. This compound crystallizes in the space group P21 with unit cell parameters a = 14.207 b = 7.752(1) c = 19.473(1) ? = 91.00(3), with two molecules in the asymmetric unit. The ketenedithioacetal functionality present between the carbonyl groups prevents the possibility of keto-enol tautomerization in this compound. The cinnamoyl groups are organized parallel to each other due to the push-pull nature of the ketenedithioacetal functionality. 2010 Springer Science+Business Media, LLC. -
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. -
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. -
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 -
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. -
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. -
Estimation of state of charge considering impact of vibrations on traction battery pack
Interest towards electric vehicle adoption is on the rise due to the lower running and maintenance cost it offers, along with zero tailpipe emissions. Range anxiety is one of the only concern that affects the adoption of electric vehicles. The state of charge of the traction battery pack has to be accurately determined and provided to the user to avoid range anxiety. Minute battery parameters has to be considered to improve the accuracy of the state of charge determination. In order to overcome the problem of range anxiety, an innovative strategy that takes into account how vibrations affect the performance of EV batteries is developed in this research. By doing this, the state of charge estimation precision is improved and thereby raises the drivers faith in electric vehicles. The impacts and vibrations felt on the traction battery pack during driving would lead to heat generation. The heat generated is found to be highest when the vibrations resonate at the natural frequencies of the traction battery pack. The natural frequency of the battery pack is considered when the battery is kept in the battery chamber of the two-wheeler electric vehicle. The vibrations at natural frequency produces heat which is accounted for when the state of charge is determined. To obtain accurate state of charge estimation, a Kalman filter-based approach is used. The Kalman filter-based estimation uses the conventional methods which are the open circuit voltage method and the Coulomb counting method to improve the estimation process along with the consideration of the heat component due to vibrations and impact. The vibration analysis is performed using MATLAB, while the state of charge determination is implemented in hardware and the Kalman estimation done using Python. The system is modelled on an electric two-wheeler platform and the testing is done to compare the state of charge accuracy of the open circuit voltage method, the Coulomb counting method and the Kalman filter-based estimation approach. The inclusion of the vibrational heat analysis for State of Charge estimation in the hardware testing of the electric two-wheeler provides an accurate state of charge value. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024. -
Assessing Housing Preferences and Living Conditions of Migrant Workers in the Fringe Areas of Bengaluru City, India
This study investigates the housing preferences and its impact on living conditions of migrant industrial workers in the fringe areas of Bengaluru, India, where rapid urbanization and economic expansion have led to a significant demand for affordable housing. Using the Analytic Hierarchy Process (AHP), a multi-criteria decision-making framework, this study analyzed key factors influencing housing choices, such as proximity to the workplace, affordability, and access to essential amenities. Data were collected from 400 respondents through a combination of surveys, complimented by field observations and expert consultations. The findings indicate a strong preference for affordable housing close to employment hubs, with proximity to workplace emerging as the most critical criterion with a priority weight of 43.36%, followed by affordability with a priority weight of 12.47%. However, field insights reveal a trade-off with housing quality and living conditions. Many migrant workers are confined to overcrowded and poorly ventilated rental units, often provided by employers, which compromises their health and well-being. Our results contribute to the understanding of urban housing challenges in rapidly growing economies and emphasize the importance of sustainable, health-oriented housing policies that can mitigate environmental impacts and improve the quality of life for low-income migrant populations. 2024 by the authors. -
Unique Host Matrix to Disperse Pd Nanoparticles for Electrochemical Sensing of Morin: Sustainable Engineering Approach
Biomass-based carbon nanospheres derived from Mimosa pudica (commonly called "Touch-me-not") smeared on carbon fiber paper have been used as a host matrix for electrochemical deposition of palladium nanoparticles. The physicochemical characterization of modified electrodes was performed by field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy techniques. Cyclic voltammetry and electrochemical impedance spectroscopy were used to study the electroanalytical properties of the electrodes. The modified electrode demostrated an excellent electrocatalytic activity for the oxidation of a flavonoid, morin, which gave a sensitive anodic peak at-0.30 V (vs SCE). An ultralow-level detection limit of 572 fM with a linear dynamic range of 37.50-130 pM was achieved. The proposed electrochemical sensor was successfully employed for the analysis of morin in mulberry and guava leaves. This is a sustainable engineering approach where a perfect unique host matrix is created using carbon nanospheres from biomass. Copyright 2020 American Chemical Society. -
A Smartphone Coupled Freshness Indicator Prepared by Rub-coating of Hibiscus Flowers on Paper substrates for Visual Monitoring of the Spoilage of Milk
This study developed an inexpensive and easy-to-use milk freshness indicator (H-Paper) by rub-coating hibiscus flowers onto paper. As per the best of our knowledge, this is the first example of a food quality indicator prepared by direct hand-rubbing of a natural halochromic material onto paper substrates. Unlike the previously reported colorimetric indicators from natural sources, our indicator does not require the extraction of anthocyanins from the natural product. The H-Paper undergoes a quantifiable color change from green to purple to pink corresponding to fresh, spoiling, and spoiled milk samples. Digital photographs of H-Paper treated with milk samples were acquired using a smartphone, and RGB indices were analyzed using a free application. The red chromatic shift was used as a parameter to quantify color change of H-Paper to follow the spoilage of milk. Anthocyanins present in the hibiscus flowers are responsible for this colorimetric response. This work demonstrates a proof-of-concept for directly rub-coating halochromic materials onto a substrate to fabricate food freshness indicators. The H-Paper indicator has advantages of naked-eye analysis, consumer-friendliness, and instrument-free operation. This requires neither any laboratory accessories nor the expertise of a trained analyst for its preparation and operation, which is appropriate for use in resource-limited settings. 2022 Wiley-VCH GmbH. -
Smartphone application-based colorimetric fish freshness monitoring using an indicator prepared by rub-coating of red cabbage on paper substrates
This work developed a simple, easy-to-prepare, and inexpensive indicator (R-Paper) based on rub-coating of red cabbage on readily available paper substrates to detect the freshness of fish in out-of-lab settings. A single-step rub-coating method was used to incorporate anthocyanins on paper substrates, without the extraction of the compound from red cabbage. The preparation of the indicator and its usage is quick and does not require additional chemicals, personnel expertise, or laboratory facilities. The functional colorimetric interface created by directly rubbing red cabbage on paper was used for fish quality monitoring, which displayed a naked-eye detectable color change from purple (for fresh fish) to blue (for spoiling fish) and then to blue-green (for spoiled fish), corresponding to total volatile basic nitrogen (TVB-N) and pH changes. To provide a user-friendly quantitative analysis of this color change, we used the free Android software Color Grab to quantify the color using L*, a*, b*, and RGB indices. To the best of our knowledge, this work is the first report on an indicator prepared by rub-coating red cabbage onto paper-based substrates for fish spoilage monitoring through smartphone-based analysis. To verify that the R-Paper indicator performs on a par with the indicators using extracted anthocyanins, its performance was compared with indicators prepared using anthocyanins extracted from red cabbage (AR-Paper). Naked-eye analysis, simple preparation, ease of use, low cost, and free smartphone-based analysis make the R-Paper indicator an appropriate food quality indicator in resource-limited areas. 2023 Elsevier B.V.