BHU Institutional Repository :: Browsing by Author "Srivastava S.K."

Browsing by Author "Srivastava S.K."

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2D material�based surface plasmon resonance biosensors for applications in different domains: an insight
(Springer, 2024) Yadav P.K.; Kumar A.; Upadhyay S.; Kumar A.; Srivastava A.; Srivastava M.; Srivastava S.K.
The design of surface plasmon resonance (SPR) sensors has been greatly enhanced in recent years by the advancements in the production and integration of nanostructures, leading to more compact and efficient devices. There have been reports of novel SPR sensors having distinct nanostructures, either as signal amplification tags like gold nanoparticles (AuNPs) or as sensing substrate-like two-dimensional (2D) materials including graphene, transition metal dichalcogenides (TMDCs), MXene, black phosphorus (BP), metal-organic frameworks (MOFs), and antimonene. Such 2D-based SPR biosensors offer advantages over conventional sensors due to significant increases in their sensitivity with a good figure of merit and limit of detection (LOD). Due to their atomically thin structure, improved sensitivity, and sophisticated functionalization capabilities, 2D materials can open up new possibilities in the field of healthcare, particularly in point-of-care diagnostics, environmental and food monitoring, homeland security protection, clinical diagnosis and treatment, and flexible or transient bioelectronics. The present study articulates an in-depth analysis of the most recent developments in 2D material�based SPR sensor technology. Moreover, in-depth research of 2D materials, their integration with optoelectronic technology for a new sensing platform, and the predicted and experimental outcomes of various excitation approaches are highlighted, along with the principles of SPR biosensors. Furthermore, the review projects the potential prospects and future trends of these emerging materials-based SPR biosensors to advance in clinical diagnosis, healthcare biochemical, and biological applications. Graphical abstract: (Figure presented.) � The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature 2024.
A near infrared MIM metamaterial absorber using SiC
(Elsevier B.V., 2024) Kumar A.; Dubey S.K.; Kumar A.; Srivastava S.K.
In this study, we introduce a metamaterial absorber operating in the near infrared region. The current metamaterial absorber (MMA) comprising Silver-SiC-Gold demonstrates an absorptivity exceeding 80% within the wavelength range of 770 nm to 1150 nm. The current metamaterials absorber exhibits independence from both polarization and incident angle. Additionally, we made comparison between the proposed Metal-Insulator-Metal (MIM) based MMA with other previously reported MMA using Silicon Carbide (SiC) and another dielectric spacer layer. � 2024
Aquatic Ecosystems Monitoring: Conventional Assessment to Advanced Remote Sensing
(CRC Press, 2024) Pandey P.C.; Srivastava P.K.; Srivastava S.K.
This book collates traditional and modern applications of remote sensing in aquatic ecosystem monitoring. It covers conventional assessment methods like sampling, surveying, macroinvertebrates, and chlorophyll estimation for aquatic ecosystem health assessment. Advanced remote sensing technology provides timely spectral information for quantitative and qualitative assessment of water quality, shoreline changes, coral bleaching, and vegetation monitoring. The book covers different types of aquatic ecosystems like wetlands, rivers, lakes, saline, and the brackish lake. It also: Reviews the latest applications of remote sensing in the monitoring and assessment of aquatic ecosystems Includes traditional methods like cartography, sampling, surveying, phytoplankton assessment, river interlinking, and chlorophyll estimation Discusses the application of multi-source data and machine learning in monitoring aquatic ecosystems Discusses aquatic ecosystem management, services, threats, and sustainability Explores challenges, opportunities, and prospects of future Earth observation applications for aquatic ecosystem monitoring The book discusses space-borne, airborne, and drone geospatial data. The parts broadly cover aquatic ecosystem monitoring, vegetation management, advanced modeling practices, and challenges. It is meant for scientists, professionals, and policymakers working in environmental sciences, remote sensing, and geology. � 2025 selection and editorial matter, Prem Chandra Pandey, Prashant K. Srivastava, Sanjeev Kumar Srivastava; individual chapters, the contributors.
Biogenic synthesis of dual-emission chlorophyll-rich carbon quantum dots for detection of toxic heavy metal ions - Hg(ii) and As(iii) in water and mouse fibroblast cell line NIH-3T3
(Royal Society of Chemistry, 2024) Pratap R.; Hassan N.; Yadav M.; Srivastava S.K.; Chaudhary S.; Verma A.K.; Lahiri J.; Parmar A.S.
Due to the excessive residues and serious adverse effects, it is urgent to develop an efficient method to detect Hg2+ and As3+ in drinking water to protect human health. In this study, a novel fluorometric sensor based on chlorophyll-rich carbon quantum dots (CQDs) for the detection of Hg2+ and As3+ ions was developed. The dual emitting (blue-green and red) CQDs were synthesized by a one-step solvothermal method using plumeria plant leaves as precursors. When Hg2+ ions were added in the presence of CQDs, the red emission (676 nm) of the CQDs was quenched (OFF), while in the presence of As3+ ions, the blue-green emission (485 nm) was enhanced (ON). The detection limits of 0.99 nM for Hg2+ and 12.15 nM for As3+ were validated for the proposed sensor. The biocompatibility, cytotoxicity, and bioimaging of the CQDs were investigated in the mouse fibroblast cell line NIH-3T3. The cellular uptake was also studied under the influence of Hg2+ and As3+ ions. Moreover, the novel chlorophyll-rich CQD-based fluorometric �ON-OFF� dual probe sensor was successfully applied to detect Hg2+ and As3+ in real water systems as well as in the mouse fibroblast cell line. � 2024 The Royal Society of Chemistry.
Boron functionalized and phosphorous doped molybdenum di-sulfide quantum dots for the photoluminescence based detection of HbA1c
(Elsevier Inc., 2024) Sagar P.; Srivastava M.; Srivastava S.K.
Highly fluorescent transition metal dichalcogenides (TMDs) based quantum dots (QDs) have been the focus of immense research owing to their bio-compatibility, non-toxicity, easy chemical synthesis and broad spectrum of applications which includes biosensing, optoelectronics, energy storage devices, etc. Herein, we present a one-step hydrothermal growth of in-situ blue fluorescent phosphorous doped-molybdenum di sulfide QDs (P-MoS2 QDs) in aqueous media. A range of functional groups over the surface of chemically synthesized P-MoS2 QDs helps in conserving its fluorescence along with high aqueous stability and solubility. Besides, remarkable photoluminescence (PL) properties of P-MoS2 QDs were then explored to concoct an optical sensor with excellent selectivity and sensitivity for glycated hemoglobin (HbA1c) followed by functionalization with boronic acid. The response of the sensor was found to be linear in the range of 2�15 %, which is under the typical physiological aliquot range (0.75�22.93 mM with limit of detection to be 77.5 ?M, under optimized conditions. Moreover, PL quenching processes and TRPL data of P-MoS2 QDs were explored to elucidate the plausible quenching mechanism which suggests mixed kind of quenching processes. In conclusion, we envisaged that the present methodology can provide an effective and potent tool for HbA1c sensing in real biological (hemolysate/whole blood-lysate) samples. � 2024 Elsevier B.V.
Challenges and Future Implications in Monitoring and Assessment of Aquatic Ecosystems
(CRC Press, 2024) Mohanty S.; Pandey P.C.; Srivastava P.K.; Srivastava S.K.
Aquatic ecosystems, encompassing freshwater and marine environments, are vital for global ecological balance and human well-being. This concluding chapter delves into the diverse classifications of aquatic ecosystems and their ecological significance, emphasizing their pivotal role in supporting biodiversity, regulating climate, and providing economic services. It discusses traditional and advanced monitoring techniques, including molecular-level monitoring with environmental DNA (eDNA), traditional in situ or lab-based experiments, and regional and global monitoring using geospatial technology consisting of remote sensing, GIS, and GNSS for providing data input and processing platform. Remote sensing, in particular, is highlighted for its ability to provide comprehensive and timely information over large spatial extents, enabling robust monitoring and assessment of aquatic ecosystems. The chapter also explores the importance of remote sensing in understanding various water quality parameters, detecting environmental changes, and assessing the impacts of climate change. Challenges associated with conventional and technological approaches to studying aquatic ecosystems are discussed, alongside recent advancements in geospatial data collection and analytics. Overall, this chapter underscores the indispensable role of remote sensing in aquatic ecosystem monitoring using derived parameters and Trophic Status Index for assessing health conditions of aquatic ecosystems. Thus, it isoffering powerful tools and techniques for sustainable management and conservation efforts. � 2025 selection and editorial matter, Prem Chandra Pandey, Prashant K. Srivastava, Sanjeev Kumar Srivastava; individual chapters, the contributors.
Design, Synthesis, DFT, docking Studies, and antimicrobial evaluation of novel benzimidazole containing sulphonamide derivatives
(Academic Press Inc., 2024) Singh K.; Singh V.K.; Mishra R.; Sharma A.; Pandey A.; Srivastava S.K.; Chaurasia H.
In silico approaches have been employed to design a new series of benzimidazole-containing sulphonamide derivatives and qualified compounds have been synthesized to analyze their potential as antimicrobial agents. Antibacterial screening of all synthesized compounds was done using the broth microdilution method against several human pathogenic bacteria, viz. Gram-positive bacteria [B. cerus (NCIN-2156), B. subtilis (ATCC-6051), S. aureus (NCIM-2079)] and Gram-negative bacteria [P. aeruginosa (NCIM-2036), E. coli (NCIM-2065), and a drug-resistant strain of E. coli (U-621)], and the compounds presented admirable MIC values, ranging between 100�1.56 �g/mL. The combinatorial analysis showed the magnificent inhibitory efficiency of the tested compounds, acquired equipotent to ten-fold more potency compared to original MIC values. An immense synergistic effect was exhibited by the compounds during combination studies with reference drugs chloramphenicol and sulfamethoxazole was presented as fractional inhibitory concentration (?FIC). Enzyme inhibition studies of all synthesized compounds were done by using peptidyl transferase and dihydropteroate synthase enzymes isolated from E. coli and S. aureus and each of the compound presented the admirable IC50 values, where the lead compound 3 bound to peptidyl transferase (of S. aureus with IC50 363.51 � 2.54 �M and E. coli IC50 1.04 � 0.08 �M) & dihydropteroate synthase (of S. aureus IC50 3.51 � 0.82 �M and E. coli IC50 2.77 � 0.65 �M), might account for the antimicrobial effect, exhibited excellent inhibition potential. Antifungal screening was also performed employing food poisoning methods against several pathogenic fungal species, viz A. flavus, F. oxysporum, A. niger, and A. brassicae. The obtained result indicated that few compounds can prove to be a potent drug regimen against dreaded MDR strains of microbes. Structural activity relationship (SAR) analysis and docking studies reveal that the presence of electron-withdrawing, polar, and more lipophilic substituents positively favor the antibacterial activity, whereas, electron-withdrawing, more polar, and hydrophilic substituents favor the antifungal activities. A robust coherence has been found in in-silico and in-vitro biological screening results of the compounds. � 2024 Elsevier Inc.
Ensemble of machine learning and global circulation models coupled with geospatial databases for niche mapping of Bell Rhododendron under climate change
(Taylor and Francis Ltd., 2024) Satish K.V.; Srivastava P.K.; Behera M.D.; Khan M.L.; Gwal S.; Srivastava S.K.
Himalayan species conservation faces major challenges due to unprecedented climate change. Alpine Rhododendrons are crucial components of Himalaya, yet their vulnerability to climate change remains poorly understood. This study examines niche shifting of Rhododendron campanulatum, a keystone species of alpine treeline, under different climate change scenarios using ensemble models. The study presents extensive use of four machine learning models and three global circulation models for niche modelling. Models achieved True Skill Statistic ?0.8, Area Under Curve ?0.9, Cohen�s Kappa ?0.7, and overall accuracy of ?0.9. Results showed distribution of R. campanulatum is governed by annual temperature range, minimum temperature of coldest month and precipitation of warmest quarter. Analyses revealed niche contraction and expansion of a 3�5%. Contractions are particularly evident at lower treeline boundaries. Both upward and downward shifts are anticipated under future climatic scenarios. � 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
Evolution of shock waves in dusty nonideal gas flow with magnetic field
(Walter de Gruyter GmbH, 2024) Shweta; Pradeep; Srivastava S.K.; Singh L.P.
This paper deals with the study of propagation of shock waves in 2-D steady supersonic magnetogasdynamics flow of nonideal dusty gas using wavefront analysis method. We derived the transport equation, which determines the condition for the shock formation. Our aim is to analyze the effect of interaction of dust particles with magnetic field in nonideal gas on the evolution of shock formation and to examine how the flow patterns of the disturbance vary with respect to the variations in the physical parameters of the medium. It is found that the presence of magnetic field plays an essential role in the wave propagation phenomena. The nature of the solution with respect to the Mach number is analyzed, and it is examined how the shock formation distance changes with an increase or decrease in the value of Mach number. Also, the combined effect of nonidealness, magnetic field, and dust particles on the shock formation distance is elucidated and examined how the formation of shocks is affected by the increase in the value of corresponding physical parameters. � 2024 Walter de Gruyter GmbH, Berlin/Boston.
Fabrication of manganese ferrite-reduced graphene oxide nanostructure as an electrode material for high performance supercapacitor
(Springer Nature, 2024) Gupta G.K.; Sagar P.; Srivastava M.; Singh A.K.; Anwar S.; Singh J.; Kumar A.; Srivastava S.K.; Srivastava A.
Recent studies corroborate spinel transition metal oxides as an apical and paramount electrode materials for supercapacitors as an energy storage device, however, some adventitious stability factors restrict their practical applications. The low specific energy and poor electrical conductivity are assumed as prime factors of concerns for these prospective electrode materials. To address such issues, in the current study, we have employed an integrative strategy to synthesize a three-dimensional hierarchical electrode material consisting of manganese ferrite-reduced graphene oxide (MnFe2O4@rGO) nanostructures by a straightforward hydrothermal procedure and subsequently explored its electrocapacitive performance. X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDAX), and X-ray photo spectrometer (XPS) have all been used to analyse the physicochemical properties of the materials. Moreover, using a three-electrode system and a 3�M KOH electrolyte solution, the electrocapacitive performances of the as-synthesised samples have been assessed through galvanostatic charge�discharge (GCD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). As-prepared hierarchical electrode material exhibits gravimetric specific capacitance of 399.17 Fg?1 at a current density of 0.65 Ag?1 with Galvanostatic charging/discharging (GCD) technique and energy density (40.05 Wh/Kg) at power density (276.2 W/Kg. Furthermore, after 5000 cycles with ~ 12% retention, the as-synthesised electrodic nanocomposite shows satisfactory GCD stability without noticeable capacitance deterioration. The MnFe2O4@rGO nano-composite, as synthesised, demonstrates impressive power/energy densities and could be investigated as a potential electrode architecture for large-scale energy storage devices. � Qatar University and Springer Nature Switzerland AG 2024.
Hydrothermally synthesized nickel ferrite nanoparticles integrated reduced graphene oxide nanosheets as an electrode material for supercapacitors
(Springer, 2024) Gupta G.K.; Sagar P.; Srivastava M.; Singh A.K.; Singh J.; Srivastava S.K.; Srivastava A.
In the present study, we have employed an integrative strategy to synthesize a three-dimensional hierarchical electrode material consisting of NiFe2O4/r-GO nanostructures using a simple hydrothermal process and subsequently explored its electrocapacitive performance. The structural and morphological characteristics of the as-synthesized NiFe2O4/r-GO nanostructure have been accessed through X-ray diffraction (XRD), Raman spectroscopy, Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and X-ray photospectrometer (XPS). The electrocapacitive performances of the as-synthesized sample have been evaluated by galvanostatic charge�discharge (GCD), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) using a three-electrode system with 3-M KOH electrolyte solution. As-prepared hierarchical electrode material exhibits specific capacity ? 362.46�F g?1 at a current density of 0.65�A g?1, suggesting good rate capability. Furthermore, NiFe2O4/r-GO-nanostructured electrode material displays a significant high energy ? 36.37 Wh/kg and power density as ? 276.22�W/kg. Moreover, the as-synthesized nanocomposite harvests a superior cycling stability over 5000 cycles without obvious capacitance attenuation. The NiFe2O4/r-GO provides rapid pathways for electron transfer and diminishes the ion diffusion routes due to NiFe2O4 over r-GO sheets, which ultimately results in exceptional electrochemical properties. Henceforth, NiFe2O4/r-GO nanocomposite which renders a new reasonable design to manifest more energy density and deliver maximum power may be enrooted as a promising/prospective electrode material due to its unique morphological properties, superior conductivity, and favorable cyclic stability in the field of energy storage applications. � 2024, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
Identifying Conservation Priority Areas of Hydrological Ecosystem Service Using Hot and Cold Spot Analysis at Watershed Scale
(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Gwal S.; Sena D.R.; Srivastava P.K.; Srivastava S.K.
Hydrological Ecosystem Services (HES) are crucial components of environmental sustainability and provide indispensable benefits. The present study identifies critical hot and cold spots areas of HES in the Aglar watershed of the Indian Himalayan Region using six HES descriptors, namely water yield (WYLD), crop yield factor (CYF), sediment yield (SYLD), base flow (LATQ), surface runoff (SURFQ), and total water retention (TWR). The analysis was conducted using weightage-based approaches under two methods: (1) evaluating six HES descriptors individually and (2) grouping them into broad ecosystem service categories. Furthermore, the study assessed pixel-level uncertainties that arose because of the distinctive methods used in the identification of hot and cold spots. The associated synergies and trade-offs among HES descriptors were examined too. From method 1, 0.26% area of the watershed was classified as cold spots and 3.18% as hot spots, whereas method 2 classified 2.42% area as cold spots and 2.36% as hot spots. Pixel-level uncertainties showed that 0.57 km2 and 6.86 km2 of the watershed were consistently under cold and hot spots, respectively, using method 1, whereas method 2 identified 2.30 km2 and 6.97 km2 as cold spots and hot spots, respectively. The spatial analysis of hot spots showed consistent patterns in certain parts of the watershed, primarily in the south to southwest region, while cold spots were mainly found on the eastern side. Upon analyzing HES descriptors within broad ecosystem service categories, hot spots were mainly in the southern part, and cold spots were scattered throughout the watershed, especially in agricultural and scrubland areas. The significant synergistic relation between LATQ and WYLD, and sediment retention and WYLD and trade-offs between SURFQ and HES descriptors like WYLD, LATQ, sediment retention, and TWR was attributed to varying factors such as land use and topography impacting the water balance components in the watershed. The findings underscore the critical need for targeted conservation efforts to maintain the ecologically sensitive regions at watershed scale. � 2024 by the authors.
Introduction to Aquatic Ecosystems - Editorial Message
(CRC Press, 2024) Pandey P.C.; Srivastava P.K.; Srivastava S.K.
This editorial chapter provides a comprehensive view of the edited book Aquatic Ecosystems Monitoring: Conventional Assessment to Advanced Remote Sensing. In today�s dynamic world, understanding and preserving aquatic ecosystems have become more critical than ever. The health of these ecosystems directly impacts the well-being of both the environment and human societies. Therefore, it is imperative to employ effective monitoring techniques to assess the status of aquatic environments accurately. This comprehensive volume delves into the spectrum of aquatic ecosystems, and their monitoring techniques, ranging from traditional methodologies to the latest advancements in technology. Through the collaborative efforts of early career researchers to esteemed authors/experts in the field, this collection offers a profound exploration of the diverse methods used for assessing and understanding aquatic ecosystems. From the serene depths of freshwater lakes to the expansive realms of the coastal zones, aquatic environments harbor an incredible array of life forms and ecological processes. However, these fragile and delicate ecosystems face myriad threats, including pollution, habitat destruction, climate change, and invasive species. Effective monitoring serves as a cornerstone in our efforts to safeguard these invaluable resources for future generations. This chapter provides a depth of insight into different aspects of monitoring aquatic ecosystems and the methods incorporated accordingly to utilize resources in a sustainable way. � 2025 selection and editorial matter, Prem Chandra Pandey, Prashant K. Srivastava, Sanjeev Kumar Srivastava; individual chapters, the contributors.
Investigation of structural and optical properties of doped and undoped Cd0.75Se0.25 chalcogenide material for thin-film solar cell application
(Springer, 2024) Singh D.K.; Srivastava A.; Singh S.; Srivastava S.K.; Kumar A.
Thin films of chalcogenide material CdxSe1?x have good optical and structural properties for the application of solar cell. Chalcogenide glass and II�VI group semiconductors have been mainly used for application in the field of electronics and optoelectronic devices. In present work, the optical and structural properties like optical band gap, Urbach energy, FWHM (Full width half maximum) of peaks value of thin films of chalcogenide Cd0.75Se0.25 have been discussed in detail. Here, the XRD and UV�Vis�s techniques have been used for material characterization. Thermal evaporation technique has been used for fabrication of thin film. The present work CdxSe1?x bulk material have excellent properties which show a new way for researchers in the field of solar cell application. � The Author(s), under exclusive licence to The Optical Society of India 2024.
Nanozymes-based multifunctional platforms for uric acid detection in patients
(Elsevier, 2024) Ojha R.P.; Srivastava S.K.; Srivastava M.; Prakash R.
Uric acid (UA), a metabolic by-product arising from purine metabolism, can result in hyperuricemia and related ailments like gout and kidney stones when accumulated excessively. In recent times, nanotechnology's emergence has opened avenues for innovative approaches in diagnostics and therapeutics. Notably, nanozymes, categorized as nanomaterials exhibiting inherent enzyme-like properties, have garnered significant interest for their potential applications in fabricating sensors for monitoring UA levels in patients. Nanozymes boast qualities, such as stability, tunability, cost-effectiveness, specificity, biocompatibility, and resilience, against challenging conditions. These attributes highlight their versatility, making them valuable for applications in sensors for the detection of ions, biomolecules, and disease biomarkers. This chapter comprehensively explores the conceptualization, fabrication, and multifaceted utilities of nanozyme-based platforms tailored for UA detection. � 2024 Elsevier Inc. All rights are reserved including those for text and data mining AI training and similar technologies.
Preface
(CRC Press, 2024) Pandey P.C.; Srivastava P.K.; Srivastava S.K.
[No abstract available]
Propagation of nonlinear wave in 2-D planar and axisymmetric non-ideal radiating gas flow under the influence of magnetic field
(Springer, 2024) Srivastava S.K.; Chaturvedi R.K.; Singh L.P.
Influence of magnetic field on the propagation of shock waves in radiation gasdynamics is analysed by using wavefront analysis method. We examined behavior of the waves propagated into the two-dimensional (2-D) steady supersonic magnetogasdynamic flow of non-ideal gas with radiation. The transport equations are derived, which determine the condition for the shock formation. The effect of non-idealness and thermal radiation and their consequences under the influence of magnetic field is studied and examined how the flow patterns of the disturbance vary with respect to the variation in the parameters of the flow. It is found that the presence of a magnetic field plays an essential role in the wave propagation phenomena. Nature of the solution with respect to Mach number is analysed, and it is examined how the shock formation distance changes with an increase or decrease in the value of Mach number. Also, the effect of non-idealness on the shock formation distance is elucidated and examined how the shock formation affects the increase in the value of non-ideal parameter in the presence of magnetic field with thermal radiation. � 2023, Indian Academy of Sciences.
Recent advancements of smartphone-based sensing technology for diagnosis, food safety analysis, and environmental monitoring
(Elsevier B.V., 2024) Upadhyay S.; Kumar A.; Srivastava M.; Srivastava A.; Dwivedi A.; Singh R.K.; Srivastava S.K.
The emergence of computationally powerful smartphones, relatively affordable high-resolution camera, drones, and robotic sensors have ushered in a new age of advanced sensible monitoring tools. The present review article investigates the burgeoning smartphone-based sensing paradigms, including surface plasmon resonance (SPR) biosensors, electrochemical biosensors, colorimetric biosensors, and other innovations for modern healthcare. Despite the significant advancements, there are still scarcity of commercially available smart biosensors and hence need to accelerate the rates of technology transfer, application, and user acceptability. The application/necessity of smartphone-based biosensors for Point of Care (POC) testing, such as prognosis, self-diagnosis, monitoring, and treatment selection, have brought remarkable innovations which eventually eliminate sample transportation, sample processing time, and result in rapid findings. Additionally, it articulates recent advances in various smartphone-based multiplexed bio sensors as affordable and portable sensing platforms for point-of-care devices, together with statistics for point-of-care health monitoring and their prospective commercial viability. � 2024 Elsevier B.V.
The growth and decay of nonlinear wave in polytropic reacting gas with small solid dust particles
(Elsevier B.V., 2024) Chaturvedi R.K.; Srivastava S.K.; Singh L.P.; Koteswararao N.V.; Makrariya A.
The aim of this study is to examine the evolutionary process of shock waves along the characteristic path under the effect of dust particles in a polytropic reacting gas. Testing the nature of the governing quasilinear of this system as a coordinate, we reconstruct the governing equations as Bernoulli's differential equation and obtain the results. The results in the characteristic plane can display a non-linear behavior in the physical plane. It is shown how the reacting gas parameter influences the evolutionary process of the compressive and expansive waves, respectively, in reacting gas flows. Also, it is shown how the existence of dust in reacting gas influences the growth and decay of the compressive and expansive waves. The transport equation leading to the evolution of shock waves is determined and used to derive the condition for the shock formation. The comparative study of the effect of reacting gas parameters and dust particles on the flow patterning and distorting of shock waves for planar, cylindrically and spherically symmetric flows is also performed. � 2023 The Physical Society of the Republic of China (Taiwan)
Trending and emerging prospects of physics-based and ML-based wildfire spread models: a comprehensive review
(Springer Nature, 2024) Singh H.; Ang L.-M.; Lewis T.; Paudyal D.; Acuna M.; Srivastava P.K.; Srivastava S.K.
The significant threat of wildfires to forest ecology and biodiversity, particularly in tropical and subtropical regions, underscores the necessity for advanced predictive models amidst shifting climate patterns. There is a need to evaluate and enhance wildfire prediction methods, focusing on their application during extended periods of intense heat and drought. This study reviews various wildfire modelling approaches, including traditional physical, semi-empirical, numerical, and emerging machine learning (ML)-based models. We critically assess these models� capabilities in predicting fire susceptibility and post-ignition spread, highlighting their strengths and limitations. Our findings indicate that while traditional models provide foundational insights, they often fall short in dynamically estimating parameters and predicting ignition events. Cellular automata models, despite their potential, face challenges in data integration and computational demands. Conversely, ML models demonstrate superior efficiency and accuracy by leveraging diverse datasets, though they encounter interpretability issues. This review recommends hybrid modelling approaches that integrate multiple methods to harness their combined strengths. By incorporating data assimilation techniques with dynamic forecasting models, the predictive capabilities of ML-based predictions can be significantly enhanced. This review underscores the necessity for continued refinement of these models to ensure their reliability in real-world applications, ultimately contributing to more effective wildfire mitigation and management strategies. Future research should focus on improving hybrid models and exploring new data integration methods to advance predictive capabilities. � The Author(s) 2024.

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