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Roxburgh was right: Aponogeton microphyllus and Aponogeton undulatus are distinct species
Aponogeton microphyllus, previously placed under the synonymy of A. undulatus, is recognized here as a distinct species based on morphology, chromosome number, and molecular phylogenetics (nuclear ribosomal internal transcribed (ITS) spacer region). Observations on the type and live specimens revealed morphological differences between the two species. Aponogeton microphyllus flowered regularly and set seeds. Aponogeton undulatus flowered rarely, did not set seeds, but showed formation of young plantlets on the inflorescence axis. Similarly, different chromosome numbers were recorded in Aponogeton microphyllus and the two forms of A. undulatus, viz., AF1 and AF2, whichoccurin distinct populations. Aponogeton microphyllus exhibited polysomaty with root-tip cells showing 2n=40, 42, and 44 chromosomes. The two forms of A. undulatus, AF1 and AF2, showed 2n=84 and 86 chromosomes, respectively. Based on the ITS data, both speciesoccupiedtwo separate clades. Plastid trnK intron region indicated a close relationship between both species. Our study suggests the need for comprehensive phylogenetic analyses of A. undulatus across its distribution range based on more advanced techniques such as high-throughput sequencing data to understand the A. undulatus species complex and to detect natural hybrids of this species. 2023, Indian Academy of Sciences. -
Power quality disturbance mitigation in grid connected photovoltaic distributed generation with plug-in hybrid electric vehicle
In the last twenty years, electric vehicles have gained significant popularity in domestic transportation. The introduction of fast charging technology forecasts increased the use of plug-in hybrid electric vehicle and electric vehicles (PHEVs). Reduced total harmonic distortion (THD) is essential for a distributed power generation system during the electric vehicle (EV) power penetration. This paper develops a combined controller for synchronizing photovoltaic (PV) to the grid and bidirectional power transfer between EVs and the grid. With grid synchronization of PV power generation, this paper uses two control loops. One controls EV battery charging and the other mitigates power quality disturbances. On the grid connected converter, a multicarrier space vector pulse width modulation approach (12-switch, three-phase inverter) is used to mitigate power quality disturbances. A Simulink model for the PV-EV-grid setup has been developed, for evaluating voltage and current THD percentages under linear and non-linear and PHEV load conditions and finding that the THD values are well within the IEEE 519 standards. 2023 Institute of Advanced Engineering and Science. All rights reserved. -
Excitation dependent emissive multi stimuli responsive ESIPT organic luminogen for monitoring sea food freshness
Excited state intramolecular proton transfer (ESIPT) organic luminophores with excitation wavelength-dependent color tunability have drawn significant attention due to their exceptional photoluminescent properties in solution and solid state. A novel salicylaldehyde-based Schiff's base molecule, (E)-N'-(3,5-dibromo-2-hydroxybenzylidene)benzohydrazide (BHN) exhibited stimuli (excitation wavelength and pH) induced changes in fluorescence properties which was utilised for applications like trace level water sensing in organic solvents (THF, acetone and DMF), detection and quantification of biogenic amines and anticounterfeiting. In the solution state, BHN rendered a ratiometric detection and quantification of ammonia, diethylamine and trimethylamine, which is further supported by DFT studies. The photoluminescent response of BHN towards various biogenic amines was later utilised to monitor shrimp freshness. The investigation carried out highlights the potential versatility of ESIPT hydrazones, which renders multi stimuli responsive behaviour that can be utilised for water sensing, anticounterfeiting and the detection and quantification of biogenic amines. 2023 Elsevier Ltd -
Protoplanetary disks around young stellar and substellar objects in the ? Orionis cluster
Understanding the evolution and dissipation of protoplanetary disks are crucial in star and planet formation studies. We report the protoplanetary disk population in the nearby young ? Orionis cluster (d? 408 pc; age ? 1.8 Myr) and analyse the disk properties, such as dependence on stellar mass and disk evolution. We utilize the comprehensive census of 170 spectroscopic members of the region refined using astrometry from Gaia DR3 for a wide mass range of ? 190.004 M? . Using the near-infrared (2MASS) and mid-infrared (WISE) photometries, we classify the sources based on the spectral index, into class I, class II, flat spectrum and class III young stellar objects. The frequency of sources hosting a disk with stellar mass <2 M? in this region is 41 7 %, which is consistent with the disk fraction estimated in previous studies. We see that there is no significant dependence of disk fraction on stellar mass among T Tauri stars (<2 M?), but we propose rapid disk depletion around higher mass stars (>2 M?). Furthermore, we found the lowest mass of a disk-bearing object to be ? 20 MJup and the pronounced disk-fraction among the brown dwarf population hints at the formation scenario that brown dwarfs form similar to low-mass stars. 2023, Indian Academy of Sciences. -
The effect of climate change on the dynamics of a modified surface energy balance-mass balance model of Cryosphere under the frame of a non-local operator
One of the major causes of the intermittent nature of long-term climate changes is the interaction between the surface energy balance and the mass balance of the Cryosphere. In this paper, the pre-existing surface energy balance-mass balance model of the Cryosphere is modified by incorporating the radiative forcing of CO2 to observe the effect of global warming on the nature of the previous model. The modified model is generalized using Caputo's non-local operator. The stability of the new model is analyzed at all the equilibrium points and also it is shown that there exists a unique and bounded solution for the modified system. Using bifurcation analysis and calculating the values of Lyapunov exponents for different fractional orders of the modified system, it is found that the system exhibits chaos for certain values of the radiating forcing of CO2 To observe and visualize the changes in the nature of the new model, the system is solved using the highly efficient 7th-order RungeKutta method. It is observed that with the inclusion of the radiative forcing of CO2, the nature of the system changes from asymptotically stable to chaotic as we decrease the order of the system. The Poincare map shows that the modified model even has characteristics of a strange attractor which is highly chaotic. The system becomes unstable when the value of the radiative forcing of CO2 is increased. As a result, the predictive power of the surface energy balance-mass balance model of the Cryosphere decreases. In addition to providing insights into the transition from stability to chaos in the Cryosphere model due to CO2 radiative forcing, this research offers a deeper understanding of the intricate interplay between climate dynamics and complex systems behavior. 2023 The Authors -
Algorithms for better decision-making: a qualitative study exploring the landscape of robo-advisors in India
Purpose: This paper explores the current state of Robo-advisory services in India. This paper further highlights the problems experienced by the service providers in disseminating the innovative business model among the Indians. Design/methodology/approach: The study adopts a qualitative approach to investigate the industry experts by conducting semi-structured interviews. The data collected were transcripted and further analyzed using the content analysis technique. Finally, the authors utilized categorization and coding techniques to frame broad study themes. Findings: The study findings reveal that the three pillars of Robo-advisory are ease and convenience, the time factor and transparency in operations. Robo-advisory services are still at a nascent stage in India. Furthermore, keeping the sentiments of Indians in mind, FinTech companies could combine automated Robo-advisory with a human touch of a wealth manager for optimal advisory services. Research limitations/implications: Since the present study is qualitative, the authors cannot generalize the study results. Future research can focus on empirically proving the constructs of the study using quantitative methods. Practical implications: Robo-advisors have a well-established market in developed nations but are still nascent in developing countries like India. The current focus of service providers and regulatory authorities must be to increase awareness among investors by educating the investors and building trust. Originality/value: The present study is the first to qualitatively synthesize the challenges faced by the FinTech service providers in the Indian market. 2023, Emerald Publishing Limited. -
Tadpole domination number of graphs
The graph obtained by joining cycle Cm to a path Pn with a bridge is called Tadpole graph denoted by Tm,n. A subset D of V (G) is said to be a tadpole dominating set of G if D is a dominating set and the set of vertices of D spans a tadpole graph Tm,n where m ? 3, n ? 1. In this paper, we find the tadpole domination number of cartesian product of certain graphs, namely, paths, cycles and complete graphs. Also the tadpole domination number for the Mycielskian of cycles and paths is obtained. 2023 World Scientific Publishing Company. -
Azopyridine as a Linker Molecule in Polyaniline-Grafted Graphene Oxide Nanocomposite Electrodes for Asymmetric Supercapacitors
Electronically conducting polymers (ECPs)/carbon nanomaterial-based polyaniline electrodes have received great interest in the field of supercapacitors due to their high specific capacitance, good electronic conductivity, good mechanical strength, good chemical and electrochemical stabilities, etc. Among the various available ECPs, they have received much importance due to their excellent electrochemical performances. Herein, we report a facile synthesis of a PANI-grafted graphene oxide (GO)-azopyridine (Azo) (PANI/GO-Azo) nanocomposite and use it as electrodes for fabricating supercapacitors. The azo units present in the nanocomposite act as a spacer between PANI and GO. The interfacial polymerization method is adopted for the synthesis of PANI/GO-Azo nanocomposites. The PANI/GO-Azo nanocomposite electrode exhibits a gravimetric capacitance of 426 F g-1 at a current density of 0.25 A g-1 in 1 M H2SO4 (aqueous) electrolyte. The electrode possesses good cycling stability of more than 5000 cycles with a Coulombic efficiency of 98.5%. An asymmetric supercapacitor fabricated with PANI/GO-Azo as the positive electrode and activated carbon as the negative electrode delivers an energy density of 12.45 W h kg-1 with a power density of 274.9 W kg-1. This study proclaims that the PANI/GO-Azo nanocomposite electrode is highly promising for next-generation supercapacitors. 2023 American Chemical Society -
One Pot Hydrothermal Synthesis and Application of Bright-yellow-emissive Carbon Quantum Dots in Hg2+ Detection
Carbon quantum dots (CQD) have drawn great interest worldwide for their extensive application as sensors due to their extraordinary physical and chemical characteristics, good biocompatibility, and high fluorescence in nature. Here, we demonstrate a technique for detecting mercury (Hg2+) ion using a fluorescent CQD probe. Ecology is concerned about the accumulation of heavy metal ions in water samples due to their harmful effects on human health. Sensitive identification and removal of metal ions from water samples are required to reduce heavy metals risk. To find out Mercury in the water sample, carbon quantum dots were used and synthesized by 5-dimethyl amino methyl furfuryl alcohol and o-phenylene diamine through the hydrothermal technique. The synthesized CQD shows yellow emission when exposed to UV irradiation. Mercury ion was used to quench carbon quantum dots, and it was found that the detection limit was 5.2 nM with a linear range of 15100 M. The synthesized carbon quantum dots were demonstrated to efficiently detect Mercury ions in real water samples. 2023, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature. -
On the secure vertex cover pebbling number
A new graph invariant called the secure vertex cover pebbling number, which is a combination of two graph invariants, namely, secure vertex cover and cover pebbling number, is introduced in this paper. The secure vertex cover pebbling number of a graph, G, is the minimum number m so that every distribution of m pebbles can reach some secure vertex cover of G by a sequence of pebbling moves. In this paper, the complexity of the secure vertex cover problem and secure vertex cover pebbling problem are discussed. Also, we obtain some basic results and the secure vertex cover pebbling number for complete r-partite graphs, paths, Friendship graphs, and wheel graphs. 2023 World Scientific Publishing Co. Pte Ltd. All rights reserved. -
Perceptual span in reading Aksharic Kannada
Perceptual span, the effective visual field in reading covered in a single fixation, varies across orthographies. The perceptual span for reading English covers 34-character spaces to the left of fixation and around 1415-character spaces to the right of the fixation while for Chinese it is one character space to the left and 3-character spaces to the right of the fixation. In the present study, we estimated the perceptual span for Kannada, a major South Indian language written in akshara (abugida type) using the gaze-contingent moving window paradigm. We recorded eye movements from skilled Kannada readers when they read sentences in different window sizes and compared the eye movement measures with that of full-length sentence reading. Results showed that the perceptual span for Kannada covers one akshara to the left and 6-akshara to the right of the fixation. Future studies need to establish whether all Akshara orthographies show a similar percentual span. 2022, The Author(s), under exclusive licence to Springer Nature B.V. -
Impacts of Pore Scale Gas Diffusion Layer Deformation on PEMFC Performance at Sub Zero Operation
Highlights Impact of assembly pressure on species and charge transport during cold start operation. Inhomogeneous GDL compression and intrusion is considered in the study. The intrusion effect leads to intense ice accumulation under the channels at 2 MPa. The importance of applying appropriate clamping pressure is highlighted in the study. 2023 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited -
A HYBRID APPROACH FOR LANDMARK DETECTION OF 3D FACES FOR FORENSIC INVESTIGATION
Facial landmark detection is a key technology in many forensic applications, such as facial identification and facial reconstruction. However, the accuracy of facial landmark detection is often limited in 3D face images due to the challenges of occlusion, illumination, and pose variations. This paper proposes a hybrid approach for landmark detection of 3D faces for forensic investigation. A hybrid method of edge contour detection and Harris corner detection is proposed for feature extraction in face images for forensic investigation. Edge contour detection is used to detect the boundaries of the face, while Harris corner detection is used to detect the corners. The advantage of using a hybrid method of edge contour detection and Harris corner detection for feature extraction in face images is that it can capture both global and local features of the face. Edge contour detection can capture global features, such as the overall shape and outline of the face, while Harris corner detection can capture local features, such as the corners of the mouth, nose and eyes which are vital for facial reconstruction. Experimental results show that the proposed method outperforms existing landmark detection algorithms in terms of time complexity and minimum loss. 2023 Little Lion Scientific. -
Travails of New Mothers Returning to Work in Corporate India: A Phenomenological Study
A womans life is a myriad of experiences and none, perhaps, leaves a more lasting impression on her than motherhood. The child-birth event along with all its highs and lows not only has a deep psychological impact on her as a person but also impacts her career in many ways. Using interpretive phenomenological analysis, we have studied the lived experience of women who returned to work in corporate settings after maternity leave. Our study found that not only do they go through an emotional upheaval during this phase, but they also see a marked shift in the way they approach their careers. A womans natural instinct to mother her child comes in conflict with another natural (and equally important) desire to succeed in the workplace. Most women in our study experienced a stalling/break in their careers after childbirth and wished they had a mentor to assist them in transitioning back to office life. Besides trying to evaluate if childbirth was perceived as a threat or potential impediment to a high-flying career, we also explored how women were treated in their work environments, and whether their coworkers helped the women to cope during this phase. While the women in our study wanted to achieve success and satisfaction both within their families and careers, they found it most challenging to do so. 2022 Journal of International Womens Studies. -
Antioxidant Phenolics of Justicia adhatoda L. and Cordia dichotoma Frost. Promote Thrombolytic Activity through Binding to a Serine Protease, Tissue Plasminogen Activator Protein
Background: The tissue plasminogen activator (tPA) protein dissolutes fibrin clots and prevents the disease like thrombosis. The current study aimed to study the tPA-promoting activity of bioactive molecules of Justicia adhatoda L (JA) and Cordia dichotoma Frost (CD). Methods: The phytochemical characterization of methanolic and aqueous extracts of JA and CD stems was performed through qualitative analysis, Fourier-transform infrared spectroscopy (FTIR), and biochemical tests (total phenolic and total flavonoid content [TPC and TFC]). The bioactivity of the extracts was studied through total antioxidant capacity (TAC) and ferric-reducing antioxidant potential (FRAP) assays. Finally, forty phytocompounds from JA and CD were identified from the literature, and in silico molecular docking study was performed to target tPA protein (PDB id 1A5H, Chain A, X-ray diffraction, resolution 2.90 . Results: Various phytochemical classes were identified from extracts, through qualitative and FTIR analysis. TPC and TFC were estimated from the JA and CD extracts within the range of 9.3428.67 mg gallic acid equivalent/100 g of extract weight (EW) and 2.4816.17 mg quercetin equivalent/100 g of EW, respectively. The aqueous extract of CD showed the highest TAC of 14.90 ascorbic acid equivalent (AAE)/100 g of EW, and the methanolic extract of JA had the highest FRAP activity of 27.77 mg AAE/100 g EW. The molecular docking study showed that apigenin 6,8-di-glucopyranoside had the highest binding potential toward the tPA (?9.380 kcal/mol). Conclusion: It can be concluded that antioxidant phytochemicals of JA and CD could promote the tPA activity, thereby promoting thrombolytic activity. Copyright: 2023 Biomedical and Biotechnology Research Journal (BBRJ) -
Nanofluid flowing over a rotating disk that is stretching and permeable: An unsteady model
The model presented in this paper deals with the investigation of the unsteady laminar flow past a stretchable disk. The nanofluids Al2O3/H2O and Cu/H2O are considered for the analysis where the thermal characteristics and flow behavior of these nanofluids are compared. In addition, the system is subjected to the suction force that has significant impacts on velocity of the nanofluid flow. Further, the nanoparticle solid volume fraction is another important parameter that is discussed which has a prominent role on both profiles of the nanofluid. Furthermore, the investigated mathematical model is framed using PDEs that are transformed to ODEs using suitable transformations. The system of equations obtained in this regard is solved by employing the RKF-45 numerical method where the results are obtained in the form of graphs. Various nanofluids flow parameters arise in the study and the impact of all these parameters has been analyzed and interpreted. Some of the major outcomes are that the higher values of nanoparticle solid volume fraction enhance the temperature while it decreases velocity of the flow. The comparison of flow of the two nanofluids concluded that aluminawater nanofluid has a better velocity while the copperwater nanofluid has a better thermal conductivity. World Scientific Publishing Company. -
Sm-MOF/rGO/PANI composite as an electrode material for supercapacitor applications
In recent years, scientists have been paying a lot of attention to metal-organic frameworks, often known as MOFs, as a possible material for use as electrodes in supercapacitors. MOFs are capable of functioning as high-quality pseudocapacitors because of their crystalline structure, which enhances the specific surface area and provide mechanical support for composite materials. The objective of this study is to synthesize an electrode material that can be used as supercapacitors by synthesizing Sm-MOF and then combining it with reduced graphene oxide (rGO) and polyaniline (PANI) to make a hybrid material. Here, the effect of incorporation of PANI and rGO in Sm-MOF is investigated, and its application as a supercapacitor is examined. Due to the high surface area and pore size, Sm-MOF/rGO/PANI material exhibits high specific capacitance. The computed specific capacitance of the composite Sm-MOF/rGO/PANI material is 1935.6 F g?1 when subjected to a current density of 1 A g?1. The Sm-MOF/rGO/PANI device is fabricated and exhibits a specific capacitance of 218 F g?1. The specific power and energy are calculated to be 59.3 Wh kg?1 and 581 W kg?1, respectively. 2023 Elsevier Ltd -
Biogenic Synthesis of Zinc Oxide Nanoparticles Mediated by the Extract of Terminalia catappa Fruit Pericarp and Its Multifaceted Applications
Zinc oxide nanoparticles (ZnO-NPs) were biosynthesized by using the pericarp aqueous extract from Terminalia catappa Linn. These NPs were characterized using various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet (UV) spectroscopy, dynamic light scattering (DLS), and scanning electron microscopy (SEM), and XRD studies of the nanoparticles reported mean size as 12.58 nm nanocrystals with highest purity. Further SEM analysis emphasized the nanoparticles to be spherical in shape. The functional groups responsible for capping and stabilizing the NPs were identified with FTIR studies. DLS studies of the synthesized NPs reported ? potential as ?10.1 mV and exhibited stable colloidal solution. These characterized ZnO-NPs were evaluated for various biological applications such as antibacterial, antifungal, antioxidant, genotoxic, biocompatibility, and larvicidal studies. To explore its multidimensional application in the field of medicine. NPs reported a potential antimicrobial activity at a concentration of 200 ?g/mL against bacterial strains in the decreasing order of Streptococcus pyogenes > Streptococcus aureus > Streptococcus typhi > Streptococcus aeruginosa and against the fungi Candida albicans. In vitro studies of RBC hemolysis with varying concentrations of NPs confirm their biocompatibility with IC50 value of 211.4 ?g/mL. The synthesized NPs DPPH free radical scavenging activity was examined to extend their antioxidant applications. The antiproliferation and genetic toxicity were studied with meristematic cells of Allium cepa reported with mitotic index (MI index) of 1.2% at the concentration of 1000 ?g/mL. NPs exhibited excellent Larvicidal activity against Culex quinquefasciatus larvae with the highest mortality rate as 98% at 4 mg/L. Our findings elicit the therapeutic potentials of the synthesized zinc oxide NPs. 2023 The Authors. Published by American Chemical Society -
Design of reconfigurable multiplier-less filter structure based on IFIR for digital channelizer
The flexibility in frequency allocation is essential for high throughput satellites (HTS). The digital channelizer based transponder system has a crucial role in enhancing the performance of HTS. In this work, the design and implementation of a low computational complexity digital channelizer for HTS is proposed. The proposed reconfigurable filter structure for digital channelizer is to generate non-uniform and sharp transition width FIR filters for transponder of the satellite systems. The multipliers and group delay needed in the digital channelizer that employ the proposed structure are reduced when compared to FRM and traditional IFIR based digital channelizer. An example is used to illustrate the effectiveness of the proposed design. Results reveal that the proposed structure has a lower multiplier complexity than existing techniques. The proposed structure once implemented effectively, the power dissipation and hardware complexity are reduced. With the help of CSD, MOABC, and SIDC-CSE optimization, the filters used in this structure are made multiplier-less. Hence this structure is adaptable for the digital channelizer in the transponder of the satellite communication systems. 2023 Elsevier GmbH -
Redefining Photography in the Era of Artificial Intelligence
[No abstract available]