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A comprehensive record of fishes and crustaceans in a poorly known tropical estuary-Kavvayi from the west coast of India
A comprehensive study conducted from 2019 to 2021 in the Kavvayi estuarine wetland along Indias southwest coast documented its fish and crustacean diversity, providing valuable insights for conservation. Monthly surveys across 19 sampling stations recorded 151 species, including 79 demersal fish, 55 pelagic fish, and 17 crustaceans from 63 families. According to IUCN criteria, 98 species are classified as Least concern, 32 as Not evaluated, 14 as 'Data Deficient',four as Vulnerable, two as Near threatened, and one as Critically endangered. Marine migrant species dominate the estuary, while freshwater species are rare. The Eupercaria order contributes significantly to finfish diversity, representing 12.58%. Families such as Carangidae (14 species), Portunidae (8), and Clupeidae (7) exhibit notable species richness. Prominent species like Ambassis gymnocephalus, Mugil cephalus, Planiliza macrolepisStolephorus indicus, Etroplus suratensis, Pseudetroplus maculatus, Sillago sihama, Caranx ignobilis, and Gerres filamentosus are consistently present throughout the year, highlighting the estuarys reliability as a habitat. This dataset not only offers a crucial inventory of Kavvayis biodiversity but also emphasizes its conservation potential. The scarcity of information on the fish and crustacean diversity underscores the importance of the dataset provided in this paper, as it will significantly contribute to the assessment for designating Kavvayi estuary as a wetland of international importance. This dataset enhances local, regional, and global fish community data for estuarine fisheries. It also addresses the challenges faced by the fishing community, emphasizing the need for conservation strategies to ensure the long-term health of the estuarine ecosystem. The Author(s), under exclusive licence to Senckenberg Gesellschaft f Naturforschung 2025. -
Biosynthesized carbon quantum dots/g-C3N4/Co3O4 composites for effective methylene blue dye degradation and DFT study
In this study, we aimed to develop a new, efficient photocatalyst, graphitic carbon nitride/carbon quantum dots/cobalt oxide (g-C3N4/CQDs/Co3O4 (CCC)), via a hydrothermal route. The composite was synthesized through a simple hydrothermal method, with the Co3O4 nanoparticles (NPs) systematically varied to 3, 5, and 10 %. The resulting samples are comprehensively characterized using various techniques, including X-ray diffraction (XRD), Raman spectroscopy, Fourier-transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), BrunauerEmmettTeller (BET) surface area analysis, vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), and ultraviolet-visible (UVVis) spectroscopy. Photocatalytic activity was evaluated using methylene blue (MB) dye under UV light. Among the prepared samples, the 3 % Co3O4 NPs loaded CCC catalyst has shown superior photocatalytic efficiency of 94.5 % within 120 min, which is higher than that of the 5 and 10 % Co3O4 NPs loaded CCC composite and better than that of the pristine materials. The results are obtained for optimized conditions at a concentration of 5 ppm, 0.05 g and pH 10. The 3 % CCC composite has exhibited excellent reusability and stability upto five cycles. Furthermore, Density Functional Theory (DFT) was used to understand the crystal structure and electronic properties of the prepared composite. The results have demonstrate that the novel CCC composite is a promising catalyst for the degradation of MB dye in aqueous solutions and environmental remediation. 2025 Elsevier B.V. -
Facile synthesis of novel ternary g-C?N?/MnO?/CQDs nanocomposite for efficient photocatalytic degradation of methylene blue and DFT study
A novel type II staggered heterojunction photocatalyst, g-C?N?/MnO?/CQDs (CCM nanocomposite), has prepared through a facile hydrothermal route using MnO? nanoparticles (NPs) varying between 3 % and 5 %. The 5 % CCM nanocomposite has exhibited superior photocatalytic performance, achieving a maximum degradation efficiency of 98.38 % for methylene blue (MB) under UV light irradiation within 120 min. This performance significantly surpassed those of pristine g-C?N? and MnO?. Kinetic analysis has demonstrated a rate constant of 2.96 10? min? and a half-life of 23.42 min under optimal conditions. The degradation efficiency gets increased from 93.15 % to 98.38 % with the increase in pH from 3 to 7, whereas higher dye concentrations (10 and 20 ppm) has resulted with the decreasing efficiencies of 87.1 % and 73.9 %, respectively. BrunauerEmmettTeller (BET) analysis has confirmed the mesoporous nature of the 5 % CCM nanocomposite, with a specific surface area of 5.27 m g?, an average pore size of 11.52 nm, and a pore volume of 0.03 cm g?. The bandgap energies are determined to be notably reduced to 2.7 eV for 5 % CCM nanocomposite. Thermogravimetric analysis (TGA) has shown the excellent thermal stability of the 5 % CCM nanocomposite up to 750 C. Vibration Sample Magnometer (VSM) analysis has specified the weak ferromagnetic behaviour. Density functional theory (DFT) calculations were performed to evaluate the electronic structure and charge-transfer mechanism underlying the improved performance. Importantly, reusability tests over five consecutive cycles showed that the 5 % CCM nanocomposite has retained 80 % of its initial photocatalytic activity, demonstrating excellent catalyst stability and potential for practical applications. 2025 Elsevier B.V. -
Trajectories forSpace Missions: Bridging Tradition andInnovation
Spacecraft trajectory optimization has always been a determining factor in successful space missions as it should be precise and efficient in automatically exploiting new opportunities present in the complex and dynamic environment. Traditional optimization algorithms cannot meet the increasing demand for fast computation, adaptation ability, or overcoming real-time constraints. A recently developed technique called reinforcement learning is quite promising in dealing with such issues by proposing innovative solutions for trajectory optimization. This paper surveys cutting-edge reinforcement learning solutions for optimizing spacecraft trajectory problems. Comprehensive and pragmatic analysis based on different aspects of currently available solutions, and concise reports are generated to get the latest update on this field, as well as provide reference on designing future-related solutions. The survey suggests that more efforts from the research field should be spent on reinforcement learning solutions especially when applied in the real mission scenario because there are still many challenges unattended by the community that were pointed out before being delivered at the end-user level. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2026. -
Categorizing Disaster Tweets Using Learning Based Models for Emergency Crisis Management
Social media communication is essential to the crisis response aftermath of a massive tragedy. Facebook, Twitter, and other social media network platforms are effective instruments for connecting and fostering collaboration among catastrophe victims and other groups. As a result, numerous research publications on tweet analysis have been released. Tweet analysis during a crisis helps in understanding the nuances of the incident. Existing works primarily focused on tweet sentiment analysis and binary categorization of tweets into catastrophe relevant or not. Our work mainly categorizes catastrophe tweets into seven categories: Blizzard, earthquake, flood, hurricane, tornado, wildfire, and not-relevant tweets. Deep learning and machine learning methods were employed to categorize the tweets. The annotated data is subjected to classification using Support Vector Machine (SVM) utilizing Term Frequency-Inverse Document Frequency (TF-IDF) Vectorizer and Word2Vec Vectorizer and compares the accuracy of different kernel functions. Bidirectional Long Short Term Memory (Bi-LSTM) is used on the labeled data as a deep learning technique. SVM exhibited 88% accuracy compared to 87% for Bi-LSTM. Empirical evidence shows that our methodology is more productive and efficient than previous approaches. From this knowledge of the incident, emergency aid organizations may draw conclusions and act immediately. 2023 IEEE. -
Classification of Disaster Tweets using Machine Learning and Deep Learning Techniques
Social networks provide a plethora of information for gathering extra data on people's behavior, trends, opinions, and feelings during human-affecting occurrences, such as natural catastrophes. Twitter is an inevitable communication medium during calamities. People mainly depend on Twitter to announce real-time emergencies. However, it is rarely straightforward if someone is declaring a tragedy. Sentiment analysis of disaster tweets aid in situational awareness and realizing the disaster dynamics. In our paper, we perform a sentimental analysis of disaster tweets using techniques based on machine learning and deep learning. The tweets are pre-processed before being converted into a structured form using Natural Language Processing (NLP) methods. Supervised learning techniques such as the Support Vector Machine and the Naive Bayes Classifier algorithm are used to develop the Classifier, which categorizes tweets into distinct catastrophes and selects the most appropriate algorithm. The chosen algorithm is further enriched with an emoticon detection algorithm for explicit elucidation. Our research would help disaster relief organizations and news agencies to conclude about the state of affairs and do the needful. 2022 IEEE. -
Characterization of the Forgotten Topological Index and the HyperZagreb Index for the Unicyclic Graphs
Let G be a molecular graph with V (G) and E(G) be the vertex set and edge set, respectively. Various investigations show that many degree and distance based topological indices are used to exhibit strong intrinsic connection between the molec- ular structures and the physico-chemical properties of the chemical compounds. In this paper, we focus on two degree-based topological indices, namely, the forgotten topological index and the hyper-Zagreb Index expressed as F(G) = P u2V (G) d(u)3 and HM(G) = P uv2E(G)(d(u) + d(v))2, respectively, where d(u) and d(v) are the degrees of the vertices u and v, respectively, in the graph G. We show that the unicyclic graphs can take any even positive integer except 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 26, 28, 30, 34, 36, 38, 42, 46, 50, 50, 54, 58, 62, 66, 70, 74, 78, 86 and 94 for the forgotten index. A comparable result for the hyper-Zagreb index is also presented. 2020 University of Kragujevac, Faculty of Science. All rights reserved. -
QSPR analysis of certain degree and eccentricity based topological indices and butane derivatives
Butane derivatives are chemical compounds formally derived from Butane C4H10 by replacement of one or more hydrogen atoms with other atoms or functional groups. In this paper, we do the QSPR analysis of few Butane derivatives with respect to some selected degree based topological indices and one eccentricity based topological index. In QSPR studies, topological indices are extensively used in determining specific bioactivity of chemical compounds. Our study showcases some important results on the correlation between Heavy atomic count, Complexity, Density, Surface tension and Index of refraction of Butane derivatives with the selected topological indices which further helps in characterizing the predicting power of these topological indices. RAS?YAN. All rights reserved. -
The QSPR study of butane derivatives: (A mathematical approach)
The QSPR analysis provides a significant structural insight into the physiochemical properties of butane derivatives. We study some physiochemical properties of fourteen butane derivatives and develop a QSPR model using four topological indices and butane derivatives. Here we analyze how closely the topological indices are related to the physiochemical properties of butane derivatives. For this we compute analytically the topological indices of butane derivatives and plot the graphs between each of these topological indices to the properties of butane derivatives using Origin. This QSPR model exhibits a close correlation between Heavy atomic count, Complexity, Hydrogen bond acceptor count, and Surface tension of butane derivatives with the Redefined first Zagreb index, the Redefined third Zagreb index, the Sum connectivity index and the Reformulated first Zagreb index, respectively. 2018 Oriental Scientific Publishing Company. All Rights Reserved. -
Extremal Trees oftheReformulated andtheEntire Zagreb Indices
The first reformulated Zagreb index of trees can take any even positive integer greater than 8, whereas the second reformulated Zagreb index of trees can take all positive integers greater than 47 with a few exceptional values less than 8 and 47, respectively. The entire Zagreb index is defined in terms of edge degrees and incorporates the idea of intermolecular forces between atoms along with atoms and bonds. This intricate significance of studying the entire Zagreb index led to the generalization of the first entire Zagreb index of trees. The inverse problem on the first entire Zagreb of trees gives the existence of a tree for any even positive integer greater than 46. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd 2024. -
Sustainable Assessment of Advanced Machine Intelligence in Clinical Safety
There is growing acknowledgment that artificial intelligence (AI) is being used to evaluate complex and vast volumes of data, producing findings without human input, in a variety of healthcare contexts, including image analysis, bioinformatics and genomics. Although this technology can offer opportunities in the diagnostic and therapeutic process, various safety-related difficulties and traps can still exist. To shed light on these opportunities and challenges, this article addresses the use of AI in healthcare and its security consequences. To deliver safer technology through AI, this research explores the cost implications of all potential technological systems, while design safety, failure safety, procedural security, and safety margins are the primary methods for identifying risks & uncertainties. Additionally, the suggestion involves the identification and distribution of explicit instructions and procedures to all relevant parties, aiming to facilitate the creation and implementation of safer Al applications within healthcare settings. 2023 IEEE. -
Augmented Reality based Navigation for Indoor Environment using Unity Platform
This paper proposes an augmented reality (AR) navigation system developed for indoor environment. The proposed navigation system is developed using Unity platform which is usually used for developing gaming applications. The proposed navigation system without the aid of Global Positioning System (GPS) tracks users position and orientation accurately by making use of computer vision and image processing techniques. The user can navigate to the desired location using its user friendly and intuitive interface. The proposed system can be extended further to provide indoor navigational guidance within lager buildings such as malls, airports, universities and medical facilities. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Complete analysis of differential cross section in 7 Li + ? ? ? 6 Li + n at astrophysical energies
We have carried out complete analysis of differential cross section in 7 Li + ? ? 6 Li + n using model-independent theoretical formalism. A complete analysis of the reaction involves measurements of not only one state of linear polarization of the photon but also another state of linear polarization inclined to the first at 45? and two states of circular polarization of the photon. An analytical study of the differential cross section including all the photon polarization states is carried out at near-threshold energies of interest to Big Bang Nucleosynthesis. 2024 IOP Publishing Ltd -
Lithium photodisintegration with linearly polarized photons at astrophysical energies
We present here a model-independent theoretical discussion of differential cross-sections in photodisintegration of lithium with unpolarized and linearly polarized photons. In recent years, experimental measurements are being carried out on the photodisintegration of lithium in the reaction channel 7Li(?, n)6Li to study the angular dependence of cross-section. In this regard, we have studied the spin structure of amplitudes in 7Li(?, n)6Li by expressing the differential cross-section in terms of Legendre polynomials. 2023 Oxford University Press. All rights reserved. -
7Li Photodisintegration withCircularly Polarized Photons
The study of photodisintegration of 7Li is of importance to Nuclear Physics, Particle Physics and Astrophysics. Primordial abundances of light elements such as D, 3He, 4He and 7Li are predicted by Big Bang theory of early universe and is of great interest to cosmologists. Lithium, being fragile gets destroyed easily at relatively low temperatures. WMAP measurements have inferred that 7Li abundance is two to three times more than that inferred by the low metallicity halo stars [1]. In recent years based on lithium isotopes series of experimental measurements are being carried out using High-Intensity Gamma-Ray Source (HIGS) at Duke Free Electron Laser Laboratory. Experiments [2, 3] were carried out, to measure the differential cross-section of the photoneutron reaction channel in photodisintegration of 7Li, where the progeny nuclei is in the ground state as well as in excited states. Theoretical study on photodisintegration of deuteron was carried out using a model-independent formalism [47] and in these studies, it was shown clearly that there could be 3 different E1? amplitudes leading to final relative n-p state. Subsequently, evidence for the existence of these three amplitudes was found in experimental studies [6] at slightly higher energies in different contexts. Using the same approach, model-independent formalism was developed for photodisintegration of 7Li [8] and an analysis was carried out to study the differential cross section with linearly polarized photons. Extending this study we propose to discuss the reaction channel 7Li+??6Li+n with initially circularly polarized photons. The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024. -
Model independent approach to photodisintegration of 7Li at the range of energies of interest to BBN
One of the elements that was synthesized primordially in the standard Big Bang Nucleosynthesis is lithium. Lithium, being fragile gets easily destroyed at relatively low temperatures in the mixing process between stellar surface and hot internal layers. So that, at the end of the stellar lifetime the lithium content is believed to be depleted. Series of experimental measurements on lithium isotopes were carried out at High Intensity Gamma Ray Source (HIGS) at Duke Free Electron Laser Laboratory. More recently experiments [1]-[2] were performed, to measure the differential cross section of the photo-neutron reaction channel in photodisintegration of 7Li, where the progeny nuclei is in the ground state as well as in excited states. The purpose of present contribution is to study the reaction channel 7Li + ? ? 6Li + n using linearly polarized photons.The model independent irreducible tensor formalism [3]-[5] will be used to study the differential cross section of the reaction. We study the angular dependence of differential cross section by expressing differential cross section in terms of legendre polynomials. In view of the several theoretical and ongoing experimental studies, a detailed theoretical study of the spin structure of the amplitudes in 7Li+ ? ? 6Li+ n and their expansion in terms of'electric' and 'magnetic' amplitudes is needed to analyze the measurements of spin observables as well as differential cross section, which leads to a better understanding of the problem at astrophysical energies. 2022 Institute of Physics Publishing. All rights reserved. -
Lithium photodisintegration with unpolarized photon beams at near threshold energies
The study of photonuclear reactions with lithium targets i.e. photodisintegration of lithium in addition to other photonuclear reactions is of considerable interest to the fields of nuclear physics, astrophysics, laser physics and several applications such as non - destructive testing of nuclear materials. We propose to study photodisintegration of lithium with unpolarized photon beams at near threshold energies. Our model independent theoretical approach, which makes use of irreducible tensor techniques, is well suited for making predictions on the spin observables as well as the differential cross section. In this paper we analyze the reaction channel 7Li + ? ? 6Li + n by using unpolarized photons. 2022 -
Green synthesis of nanoparticles from biodegradable waste extracts and their applications: a critical review
The contemporary world is concerned only with non-biodegradable waste management which needs more sophisticated procedures as compared to biodegradable waste management. Biodegradable waste has the potential to become useful to society through a simple volarization technique. The researchers are behind sustainable nanotechnology pathways which are made possible by using biodegradable waste for the preparation of nanomaterials. This review emphasizes the potentialities of biodegradable waste produced as a viable alternative to create a sustainable economy that benefits all humans. Volarization results in the utilization of biowastes as well as provides safer and hazard-free green methods for the synthesis of nanoparticles. Starting from different sources to the application which includes therapeutics, food industry and water treatment. The review hovers over the pros and cons of biowaste-mediated nanoparticles and concludes with possible advances in the application. In the present scenario, the combination of green synthesis and biowaste can bring about a wide variety of applications in nanotechnology once the hurdles of bulk-scale industrial production are resolved. Given these points, the review is focused on the cost-effective synthesis of metal and metal oxide nanoparticles. 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG. -
Synergistic g-c3n4/v2o5/pani composite for electrochemical energy storage
This work illustrates the synthesis of a ternary hybrid composite (g-C3N4/V2O5/PANI) from graphitic carbon nitride, vanadium pentoxide, and Polyaniline via hydrothermal method followed by in-situ polymerization. Morphological analysis confirms the integration of vanadium pentoxide (V2O5) and polyaniline (PANI) within the interlayer spaces of graphitic materials. The resultant hybrid composite structure facilitates rapid diffusion and ion movement at the electrode-electrolyte interface. Additionally, incorporating V2O5 within a polymer matrix alongside graphitic material generates diverse electrical profiles, enhancing electrochemical performance. The electrochemical characteristics of g-C3N4/V2O5/PANI composites were examined by Cyclic voltammetry (CV), Galvanostatic charge-discharge (GCD), and Electrochemical impedance spectroscopy (EIS). The GCD analysis shows that the g-C3N4/V2O5/PANI composite exhibits a specific capacitance of 880 Fg?1 at a current density of 1 Ag?1, retaining 78 % of its initial capacitance after executing 2000 cycles at 3 Ag?1. Furthermore, a symmetric supercapacitor was constructed using g-C3N4/V2O5/PANI composite material as the electrode, showing a capacitance of 246 Fg?1 when measured at an input current density of 1 Ag?1. This study demonstrates g-C3N4/V2O5/PANI is a potential electrode material for supercapacitor application. 2024 -
Defect engineered unzipped multiwalled carbon nanotube/vanadium pentoxide composite for high-performance supercapacitor application
In the pursuit of next-generation energy storage systems, the advancement of high-performance electrode materials with enhanced capacitance and durability remains critical. This study presents a binary composite of unzipped multi-walled carbon nanotubes (UzMWCNTs) integrated with vanadium pentoxide (V2O5). The unzipping process introduces surface defects and oxygen functional groups, which enhance dispersion and provide numerous active sites. V2O5 nanoparticles uniformly anchor onto the UzMWCNT surface, offering pseudocapacitive behavior and boosting redox activity. The synergistic interaction between electric double-layer capacitance and faradaic charge storage delivers superior electrochemical performance. Structural and morphological characterization confirms successful composite formation, while electrochemical evaluations reveal a specific capacitance of 1135 F g?1 and cycling stability with 88% retention over 2000 cycles. This work highlights the potential of UzMWCNT/V2O5 hybrids as promising candidates for high-efficiency, next-generation supercapacitor electrodes. This journal is The Royal Society of Chemistry, 2026