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Hi line analysis of Herbig Ae/Be stars using X-Shooter spectra
Herbig Ae/Be stars are intermediate-mass pre-main sequence stars undergoing accretion through their circumstellar disk. The optical and infrared (IR) spectra of HAeBe stars show Hi emission lines belonging to Balmer, Paschen and Brackett series. We used the archival X-Shooter spectra available for 109 HAeBe stars from Vioque et al. (2018) and analysed the various Hi lines present in them. We segregated the stars into different classes based on the presence of higher-order lines in different Hi series. We discussed the dependence of the appearance of higher-order lines on the stellar parameters. We found that most massive and younger stars show all the higher-order lines in emission. The stars showing only lower-order lines have Teff< 12 , 000 K and an age range of 510 Myr. We performed a case B line ratio analysis for a sub-sample of stars showing most of the Hi lines in emission. We noted that all but four stars belonging to the sub-sample show lower Hi line ratios than theoretical values, owing to the emitting medium being optically thick. The Hiline flux ratios do not depend on the stars spectral type. Further, from the line ratios of lower-order lines and Paschen higher-order lines, we note that line ratios of most HAeBe stars match with electron density value in the range of 10 9 10 11 cm - 3 . The electron temperature, however, could not be ascertained with confidence using the line ratios studied in this work. 2023, Indian Academy of Sciences. -
Hidden Markov Model: Application towards genomic analysis
Hidden Markov Model (HMM) has become one of the interesting methods for the researchers, especially in bioinformatics where different analysis are carried out. These are widely used in science, engineering and many other areas such as bioinformatics, genomic mapping, computer vision, finance and economics, and in social science. HMMs require much smaller training sets, and that the examination of the inner structure of the model provides often a deeper understanding of the phenomenon. In this survey, we first describe the important algorithms for the HMMs, and provide useful comparisons, aiming at their advantages and shortcomings. We then consider the major g applications, such as annotations, gene alignment and profiling of sequences, DNA structure prediction, and pattern recognition. We also list some analysis on how to use HMM for DNA genomes. Finally, we conclude use and perspectives of HMMs in bioinformatics and provide a critical appraisal for the same. 2016 IEEE. -
Hierarchical BiFeO3/Cr2CTx MXene composite as a multifunctional catalyst for hydrogen evolution reaction and as an electrode material for energy storage devices
A multifunctional hierarchical Bismuth ferrite/chromium carbide (BiFeO3/Cr2CTx) MXene has been employed as both electrode material for supercapacitors as well as an electrocatalyst for electrocatalytic water splitting. Here, a facile method is suggested for synthesizing Cr2CTx MXene from the chromium aluminum carbide (Cr2AlC) MAX Phase. X-ray diffraction studies, Scanning electron microscopy, and high-resolution transmission electron microscopy indicate that the aluminum atomic layers are removed from Cr2AlC MAX structure. The electrochemical test reveals that the BiFeO3/Cr2CTx MXene composite, which is produced with less Al2O3, performs well in the hydrogen evolution reaction (HER) with a low overpotential of 128 mV in 1 M potassium hydroxide. 53.3 mV dec?1, and 0.16 ? cm?2, respectively, are the values of the calculated Tafel slope and charge transfer resistance. In a dielectrode electrolysis system, BiFeO3/Cr2CTx MXene electrode needs only 1.81 V of cell potential to provide 10 mA cm?2 with long-term stability. The specific capacity of 671.2 C g?1 at a current density of 1 A g?1 is obtained for BiFeO3/Cr2CTx MXene electrode with 90% capacitance retention after 3000 cycles. The potential use of BiFeO3/Cr2CTx MXene towards HER and supercapacitor application is demonstrated by this study, which offers a gentle path for the fabrication of Cr2CTx MXene composites for energy storage and HER applications. 2023 Elsevier Ltd -
Hierarchical Demographic Classification Using Multi-output CNN
This work constructs a multi-output Convolutional Neural Network (CNN) for demographic classification, including age estimation, gender determination, race categorization, and geographical subcategories of South Asia, North Asia, Europe, and Africa. Sub-region classification is further carried out in the Indian subcontinent: Karnataka, Kerala, Tamil Nadu, Punjabi and Kashmiri. The proposed CNN is trained using a heterogeneous dataset and its performance is compared with some robust pre-trained models such as VGG16, ResNet50, InceptionV3, and DenseNet121. The proposed custom CNN architecture makes use of convolutional layers for feature extraction, dropout for regularization, and custom loss weights for balanced multi-task learning. Experimental results are showing high accuracy values of 97% for age estimation, 99.55% for gender classification, and 98.4% for region and sub-region classification. The performance of the model gives a sign of its ability to handle demographic diversity while striving to minimize bias compared to its currently existing solutions. This work provides a foundation for future advancements in hierarchical facial recognition and demographic classification with an emphasis on ethical AI and fairness in real-world applications, including overcoming dataset limitations, exploring hybrid models, and incorporating multimodal data to give more inclusivity and precision. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2026. -
Hierarchical Mapping-Partitioning-Search with Attention-Weighted Communication for UAV Swarms in Search and Rescue Operations
UAV swarm Search and Rescue (SAR) operations demand intelligent coordination to function efficiently in unfamiliar terrains while maintaining communication under bandwidth limitations. To address this, we propose a Hierarchical Mapping-Partitioning-Search (HMPS) framework that combines quadtree-based adaptive partitioning of the search area with deep reinforcement learning for region selection, together with an Attention-Weighted Flooding (AWF) communication protocol to enhance swarm coordination. The HMPS framework adapts search granularity to uncertainty and obstacle density, uses a Deep Q-Network (DQN) to learn a region-selection policy, and employs a lightweight local coverage planner to improve exploration efficiency. The AWF protocol prioritizes message relays based on content and link quality, reducing bandwidth while preserving essential information flow. This paper presents HMPS as a practical option for autonomous swarm SAR operations, and reports encouraging preliminary results in GPS-denied terrains. 2025 IEEE. -
Hierarchical porous covalent organic framework-based sensor for the detection of neurodegenerative disorder biomarkers
Guanosine is an essential biomarker that enacts an important role in neuroprotection against brain-related activities, influences the metabolism of fatty acids, and assists in the improvement of the gastrointestinal tract. A facile and selective electrochemical sensor has been developed for the sensing of guanosine based on a hierarchical porous covalent organic framework. Owing to the distinctive 2D porous architecture and ordered framework of TpBD-COF, the irreversible electrooxidation of guanosine occurred at 1.03 V (vs. SCE) in phosphate buffer solution at pH 6. The anodic peak currents under optimal conditions were linear with guanosine concentration within the range of 0.123720 ?M with a LOD of 40.63 nM under various optimal conditions. Moreover, the developed biosensor was used to determine guanosine in pharmaceutical tablets to confirm its potential application in the healthcare industry. 2023 Elsevier B.V. -
Hierarchical Retrieval Augmentation Generation for Multimodalized Woman's Companion
Empowering Women in society currently face many health-related problems due to the lack of health literacy. Specifically, people are not open to talking about such as sexually transmitted diseases and mental health problems, and counselling is considered taboo in most parts of the world. Some female children grow up under the care of single fathers who are sometimes unaware of the menstrual cycle and the necessary precautions. The solution presented by the research to overcome the problem is a women's health chatbot using Large Language Models (LLM). The research proposes an enhanced retrieval augmentation generation (RAG) architecture that uses the Cloudbased API to get a faster response from the LLM. The women's health chatbot secures data privacy by not saving conversations and being available for 24 hours. Addressing various women's health concerns-such as menstrual health, mental health, pregnancy, and menopause-the chatbot employs the LangChain framework for processing and indexing health-related documents into a vector store for efficient retrieval. The chatbot also features an alert mechanism to identify critical conversations, such as those involving suicidal thoughts, and sends alerts to specified contacts. This integrated approach aims to improve access to accurate health information and support women to make informed health decisions. 2025 IEEE. -
Hierarchically nanostructured ZnO with enhanced photocatalytic activity
Hierarchical nanostructures of ZnO are integrated architectures comprising well-ordered nanoscale subunits and excellent photocatalytic properties. In this study, synthesis of ZnO nanoparticles using methods such as co-precipitation, hydrothermal, thermal decomposition, and electrochemical precipitation yielded microsphere, nanorod, pyramid, and nanopetal-like morphologies, respectively. The catalysts obtained were characterized using XRD, IR, SEM-EDX, UVDRS, TGA, PL, and Zeta potential analysis. The XRD spectra confirmed that all the different morphologies of ZnO have hexagonal wurtzite structures The photocatalytic activity of these nanostructures was determined using a dye degradation study on a model pollutant Methylene Blue (MB) under simulated visible light. The kinetic study of the dye degradation reveals that it obeys pseudo-first-order kinetics with a maximum rate constant of 0.01503 min-1. The nanorod structured ZnO particles prepared by the hydrothermal method showed the best catalytic activity. 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited. -
Hierarchically porous MN-MOFS composite with RGO as an efficient electrode material for supercapacitor application /
Patent Number: 202241046378, Applicant: Sruthi Rajasekaran.
The present invention shows the energy storage application of the manganese-reduced graphene oxide metal organic frameworks (Mn-rGO MOFs) using the ligand, pyridine 2,6 dicarboxylic acid (PDA), under mild conditions. The methodology followed was hydrothermai at 160°C with manganese sulfate as metal salt, rGO along with the PDA ligand in pyridine, and water as solvent. The development of efficient Mn-rGO MOFs is suitable for supercapacitance energy storage applications, which is the future need for various industrial applications. -
Hierarchically porous MN-MOFS composite with RGO as an efficient electrode material for supercapacitor application /
Patent Number: 202241046378, Applicant: Sruthi Rajasekaran.
The present invention shows the energy storage application of the manganese-reduced graphene oxide metal organic frameworks (Mn-rGO MOFs) using the ligand, pyridine 2,6 dicarboxylic acid (PDA), under mild conditions. The methodology followed was hydrothermai at 160°C with manganese sulfate as metal salt, rGO along with the PDA ligand in pyridine, and water as solvent. The development of efficient Mn-rGO MOFs is suitable for supercapacitance energy storage applications, which is the future need for various industrial applications. -
Hierarchically porous RhB-encapsulated ZIF-7 as a dual-emission fluorescence probe for ultrasensitive detection of melamine in infant formulations
Melamine is an unauthorized food additive and a highly concerning adulterant in foods that can occur either accidently or intentionally in dairy products, with potential health risks upon exposure to higher concentrations. An ultrasensitive fluorescent probe based on dual emissive RhBx@ZIF-7 was developed to detect melamine. In this study, a fluorescent dye, Rhodamine B (RhB), was successfully encapsulated into the metal-organic framework (MOF) pores of ZIF-7 to form a fluorescent probe (RhB30@ZIF-7), with dual emission properties to enable the detection of melamine at low concentrations. RhB30@ZIF-7 was optimized by varying experimental parameters, including temperature (25 C), pH (7.0), incubation time (10 min), and probe concentration (1 mg mL?1), to enhance its sensitivity and selectivity. The observed fluorescent quenching towards melamine was primarily attributed to the mechanisms of the internal filtering effect (IFE), due to absorption of the excitation wavelength by melamine, causing a turn-off response in the system. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.47 ?M and 1.4 ?M, respectively, with an R2 of 0.99. This study reveals the previously unexplored enhanced fluorescence of RhB30@ZIF-7 and elucidates the contribution of the intermolecular interaction between RhB and ZIF-7 to fluorescence sensing, paving the way for food safety monitoring. 2025 RSC. -
High Gain Miniature Antenna Arrays for 2.4 GHz Applications
In this paper, miniature corporate feed Four Element Array (FEA), Eight Element Array (EEA) and Sixteen Element Array (SEA) are presented. The proposed antenna arrays are created on Rogers Duroid 5880 substrate with permittivity 2.2 and thickness of 0.782 mm. Initially, a single element antenna was created, then it was used in a corporate feed network designed for the 4-element array. As an extension, the 4-element array was used as a template and created an 8-element array and 16-element array to achieve high gain and directivity at 2.4 GHz. The proposed FEA, EEA, and SEA exhibit reflection coefficients of -25.55 dB, -37.14 dB, and -30.61 dB respectively. The peak gains obtained are 11.5 dB, 13.67 dB, and 16.76 dB respectively for FEA, EEA, and SEA. Also, the directivity has improved corresponding to the increase in the number of elements. Therefore, it can be a suitable candidate for applicationswhere extended range and coverage with better signal quality and higher data transfer rates is a priority. 2024 IEEE. -
High gain ultra wideband fractal antenna
A high gain Compact Octagonal Ultra-wideband Fractal Antenna (COUFA) using the Dual Layer Meta Frequency Selective Surface Reflector (DLMFSSR) is presented in this manuscript. The proposed Frequency Selective Surface (FSS) provides a suitable reflection phase to act as a reflector and is capable of enhancing the gain of the antenna in its wide operating bandwidth. The proposed antenna design provides better impedance bandwidth of 2-10.37 GHz with significant increase in the gain of 0.41-11.83 dB at various resonance frequencies in comparison with the antenna without reflector. The complete antenna with DLMFSSR is designed and simulated using High Frequency Structure Simulator (HFSS). The Proposed antenna, FSS are fabricated and the numerical results for return loss S11, VSWR and gain are demonstrated. Simulation and fabrication results are found to be worthy, which suites the design malleable enough for several modern UWB wireless applications. Copyright 2019 American Scientific Publishers All rights reserved. -
High performance computational method for fractional model of solid tumour invasion
The behaviour of the solid tumour invasion system in the sense of Caputo fractional with time ? and space x is analyzed by the high performance computational method: q-Homotopy Analysis Transform method (q-HATM). The existence of the solutions has been verified with the assist of fixed point theorem and derived numerical solution for different values of ?,?,h. The novel simulation for all cases is explained through figures. We derived that the method is very efficient for analyzing the behaviour of the epidemiological system. 2023 THE AUTHORS -
High Performance Ferrocene Immobilized Electrodes for the Synthesis of 3-Acetyl Coumarin: A Sustainable Approach
An electrocatalyst was developed for the synthesis of 3-acetyl coumarin, a known anticoagulant, anti-inflammatory, and anti-microbial compound, by constructing and employing an electrocatalyst with immobilized ferrocenyl aniline onto electro-polymerized anthranilic acid, on a carbon fiber paper electrode. The effectiveness of the modified carbon fiber paper electrode was assessed by analyzing its physicochemical and electrochemical properties, using optical profilometry, field-emission scanning electron spectroscopy (FE-SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), cyclic voltametric techniques and electrochemical impedance spectroscopy (EIS) respectively. 3-acetyl coumarin was synthesized using salicylaldehyde and ethyl acetoacetate as starting materials in the presence of piperidine, with lithium perchlorate as supporting electrolyte and ethanol as solvent, at potentiostatic conditions. The reaction was carried out in a three-electrode, single compartment system, at ambient conditions for three hours by using a constant potential of ?1.4 V. The product was purified by column chromatography and characterized by using gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance spectroscopy (1H-NMR). The developed electrode was found to be highly efficient towards the synthesis of 3-acetyl coumarin with a good yield of 78%, thereby proving the efficiency and selectivity of the process. 2025 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited. All rights, including for text and data mining, AI training, and similar technologies, are reserved. -
High performance symmetric supercapacitor based on microporous PANI@?-Fe2O3/MXene hybrid nanocomposite
MXene (Ti3C2Tx), a 2D layered material, has become a trending topic in the field of energy storage, due to its high-power density, flexibility, hydrophilic nature, and ease at which it can form composites with polymers, CNTs, metal oxides, and more. However, the layers of MXene restacks quite easily restricting the number of active sites to the flow of charges. Herein, we have synthesized tri-composite of Ti3C2Tx, ?-Fe2O3, and polyaniline (PANI@?-Fe2O3/Ti3C2TX) via hydrothermal treatment followed by oxidative polymerization. The insertion of ?-Fe2O3 broadens the interlayer distance allowing easy charge/discharge of ions, further addition of PANI enhanced MXenes energy density without altering its power density making MXene more reliable material for energy storage application. The composite exhibits a very high and notable electrochemical performance with 2689.3 Fg?1 specific capacitance at a current density of 1 Ag?1 compared to that of bare MXene (402 Fg?1 at 1 Ag?1). The retention capacitance of 120.7% over 5000 cycles is reported making MXene a promising material in reducing the volume expansion of PANI. A symmetric supercapacitor was fabricated exhibiting a very high energy density of 75.60 Wh kg?1. This work intends to increase MXenes performance favoring hybrid energy storage systems. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025. -
High surface area Nanoflakes of P-gC3N4 photocatalyst loaded with Ag nanoparticle with intraplanar and interplanar charge separation for environmental remediation
The photocatalytic performance of gC3N4 is majorly restricted by insufficient collection of photogenerated charges on the surface during reaction due to highly dense stacking of lamellar structures with lateral size ranging in microns. This deficiency can be overcome by forming thin nanoflakes by systematically breaking the weak bonds that hold the gC3N4 framework without destroying the basic heptazine unit. With this aim, herein, a combination of three different strategies was implemented to design and develop, Ag-loaded and P-doped gC3N4 nanoflakes (Ag3-P1-NF-gC3N4). Using a systematic synthesis method, bulk gC3N4 was first converted into thin nanosheets, followed by fragmentation into nanoflakes, with a planar size up to 100 nm. P doping to replace the corner C atoms in the gC3N4 matrix (forming P[sbnd]N bonds) and intercalation of plasmonic Ag nanoparticles within the interlayers also assists in the bifurcation of the stacked layers and formation of nanoflake morphology. These strategies result in a significant increase in BET surface area to ?196 m2/g from 12 m2/g of bulk gC3N4. Improved inter-planar and intra-planar charge mobility was recorded as a result of the reduced sizes. Doping with P also causes higher absorption of the visible spectrum in gC3N4 while the formation of heterojunction with Ag nanoparticles induces efficient separation of photo-generated charges. All these promoting photo-physical properties lead to an outstanding photocatalytic activity towards degradation of aqueous pollutants with reaction rates ?20 times higher than bulk gC3N4. Complete mineralization of the pollutant and formation of non-toxic byproducts was also confirmed with suitable chromatography techniques. 2020 Elsevier B.V. -
High trait emotional intelligence lessens the impact of the dark triad on trolling propensity
Trolling is a pervasive form of online aggression, often rooted in adverse personality traits and amplified by the disinhibiting affordances of social media. The current study applies the I3 aggression model to examine the role of Dark Triad (DT) traits as impelling factors that increase trolling propensity, and Trait Emotional Intelligence (TEI) as an inhibiting factor that could constrain such behavior. The study also investigates whether TEI buffers the impact of DT traits on trolling and whether age further moderates this moderating effect. A total of 427 adult social media users (Mage = 22.71 years, SD = 3.71) participated in the study. Correlation analysis indicated that all three DT traits were positively correlated with trolling propensity, whereas TEI showed a negative association. Hierarchical regressions demonstrated that all three DT traits uniquely and positively predicted trolling. Machiavellianism and narcissism emerged as robust predictors even after accounting for shared variance with more callous traits such as psychopathy. TEI remained a significant negative predictor, and higher TEI levels attenuated the influence of each DT trait on trolling. Three-way interactions further suggested that the protective role of TEI in the relationship between psychopathy and trolling became stronger with age. Still, this pattern did not generalize to Machiavellianism or narcissism. Although three-way interactions were modest and inconsistent across traits, they underscore a concerning developmental trend as trolling appears to be most pronounced when dark traits surface during the emotionally formative period of emerging adulthood. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2026. -
High-affinity binding of celastrol to monomeric ?-synuclein mitigates invitro aggregation
?-Synuclein (?Syn) aggregation is associated with Parkinsons disease (PD). The region ?Syn36-42 acts as the nucleation 'master controller and ?Syn1-12 as a secondary nucleation site. They drive monomeric ?Syn to aggregation. Small molecules targeting these motifs are promising for disease-modifying therapy. Using computational techniques, we screened thirty phytochemicals for ?Syn binding. The top three compounds were experimentally validated for their binding affinity. Amongst them, celastrol showed high binding affinity. NMR analysis confirmed stable ?Syn-celastrol interactions involving several residues in the N-terminus and NAC regions but not in the C-terminal tail. Importantly, celastrol interacted extensively with the key motifs that drive ?Syn aggregation. Thioflavin-T assay indicated that celastrol reduced ?Syn aggregation. Thus, celastrol holds promise as a potent drug candidate for PD. Communicated by Ramaswamy H. Sarma. 2023 Informa UK Limited, trading as Taylor & Francis Group. -
High-Efficiency Five-Level Multilevel Inverter for Grid-Connected Renewable Energy Systems: Modeling and Simulation
This paper describes the design of a 5-level multilevel inverter for grid connected renewable energy systems simulated using MATLAB. The inverter developed works with an input voltage of 164 V and a well-regulated output voltage of 325.4 V, with the switching frequency fixed at 20 kHz for efficiency, while controlling the modulation index (M) for proper voltage regulation. The performance review of the inverter such as THD and power factor were simulated with MATLAB. It is found that the voltage quality has been greatly improved and harmonic vicious generation has been diminished when compared with traditional inverter. The high-quality of output voltage provided by the inverter also makes it ideal for use with renewable energy systems. The simulations also demonstrate the efficiency of the inverter when controlling power for grid connection, revealing its capability to offer secure and low-cost renewable energy solutions. Performance evaluations indicate improved voltage waveform quality and higher efficiency of the system, which makes it promising for future renewable energy connected applications. The fact of using MATLAB simulations to verify our designs further proves its feasibility and efficacy in handling the challenges of power conversion in sustainable energy systems. 2026 IEEE.