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The present study aimed to understand the debris flow characteristics in view of frequent extreme rainfall events, expansion of road networks, tourist influx, and population pressure in the NW & Central Himalaya. Notably, majority of the human settlements, roads, bridges, buildings, and even protection measures in the NW & Central Himalaya do not take into consideration such debris flow impact scenario despite a history of debris flow disasters. The Voellmy-Salm rheology dependent dynamic runout simulation method was used to determine the debris flow pressure and velocity regime in 9 debris flow locations belonging to different litho-tectonic conditions. Results revealed that the debris flow pressure and velocity in these 9 studied debris flows might reach up to 3000 kPa and 20 m/s, respectively. The debris flow pressure and velocity of these orders have the potential to damage the protection measures and infrastructures, which have also been observed in other hilly terrains. The sensitivity analysis was carried out at a range of input parameters by considering 729 possible simulations and debris flow pressure and velocity are found to follow relatively better corelation until ~ 250 kPa flow pressure and ~ 15 m/s velocity thresholds. The influence of slope topography on the debris flow characteristics is also observed in the form of amplification of flow pressure and velocity at concave portions. The rapid development of road network in the NW & Central Himalayan region and its subjectivity to potential debris flow risk is also discussed. [ABSTRACT FROM AUTHOR]

The electronic structure calculations show that the GaS and MoS2 monolayer and MoS2/GaS hetero‐bilayer systems are semiconducting materials. It is also justified by the density of states. In the hetero‐bilayer system, the band gap is reduced. It causes an increase in the absorption, compared to their monolayers, of incident light in the visible region. This may be because of the charge transfer and the interlayer interaction between these monolayers in the heterostructure form. The calculated higher extinction coefficient causes the fast absorption of light, hence, the increased absorption coefficient. The heterostructure system makes the refractive index and reflection coefficient of GaS and MoS2 monolayers tuneable. The static reflection coefficient is in the following order GaS < MoS2/GaS < MoS2. It means that the MoS2/GaS heterostructure system can increase the static refractive index of GaS and decrease that of MoS2 monolayers simultaneously. The calculated band edge positions show that the MoS2 and GaS monolayers have excellent water oxidation and reduction capability, respectively. These predictions show that the proposed heterostructure may be a potential candidate for nanoelectronics and optoelectronics. [ABSTRACT FROM AUTHOR]

A KOtBu‐promoted robust strategy has been described for the regioselective synthesis of pyrrolo[3,4‐b]quinolin‐1‐one and naphthyridin‐1(2H)‐one derivatives from o‐alkynylquinolinecarbonitriles in good to excellent yields. The reaction proceeds through in situ transformation of the nitrile moiety into an amide group followed by the selective C−N bond formation through a 5‐exo‐dig or 6‐endo‐dig annulation reaction. Among the synthesized derivatives, 6‐endo‐dig naphthyridin‐1(2H)‐ones displayed good photophysical properties. The present approach is superior to other established methodologies as it avoids use of transition metals and column chromatographic purification and affords the products in high yields. Additionally, the current methodology provides several additional advantages, such as one‐pot operation, high atom economy, broad substrate scope and a step‐economical process. [ABSTRACT FROM AUTHOR]

The judicious use of different organic and inorganic nutrient sources is of prime importance for enhancing the productivity of long-duration and nutrient-exhaustive crops, including sugarcane. We aimed to assess the impact of optimum nutrient application through integration of bio-products and inorganic fertilizers on growth, yield of sugarcane, and N availability in sugarcane plant crops raised through bud chip settlings. The fifteen treatment combinations were replicated three times in randomized block design. Results revealed that 150% of RDF + 5 t vermicompost ha−1 + 25 kg ZnSO4 + Azotobacter + phosphate solubilizing bacteria recorded the highest growth in terms of plant population, drymatter production, cane diameter, millable canes and single cane weight; cane yield (138.7 t ha−1) and net returns (Rs. 2, 62, 600 ha−1) followed by 150% RDF + 5 t vermicompost + 25 kg ZnSO4 ha−1 in sugarcane. However, maximum benefit: cost ratio was evidenced with 150% RDF alone (1.80) and lowest in RDF + 5 t vermicompost ha−1 (0.78), respectively. NO3-N, exchangeable NH4+-N, hydrolyzable NH4+-N were found to represent about 20.5 to 30.9, 41.5 to 73.8, 55.8 to 76.8 mg kg−1, respectively. The relative contents of these fractions were in the order: non-hydrolysable > unidentified N > amino acid N > hydrolyzable NH4+-N > exchangeable NH4+-N > NO3-N > hexose amine N. Thus, the integration of organic sources with NPK holds great promise to increase cane yield and N availability in soil but with 150% RDF proved to be more remunerative and economically sound for the bud chip raised sugarcane. [ABSTRACT FROM AUTHOR]

Quinoline is one of the most important nitrogen containing heterocycles, being widespread in nature and present in a broad variety of pharmacologically active compounds. Specifically, several quinoline based renowned antimalarial agents have served the mankind for several past decades and showed strong potential applications in other field also. 3‐Formyl‐quinoline is a versatile precursor which can be transformed using several easy methods into a wide range of biologically valuable scaffolds. The exploration of 3‐formyl‐quinolines have gained much more attention to medicinal chemists in the field of drug discovery to design and synthesize new fused/tethered quinolines as potent therapeutical agents. This manuscript summarizes the reports (from 2011 to 2023) which showing the synthetic potential of quinoline‐3‐carbaldehydes. [ABSTRACT FROM AUTHOR]

In this paper, we deal with the construction of quadratic invariants in a complex phase space under the transformation z = (x + iy) and z ¯ = (x - i y) for various time-dependent systems. For this purpose, Struckmeier and Riedel (SR) approach [ 1, 2 ] is used. The constructed invariants include an unknown function f 2 (t) that is a solution of a third-order differential equation and its coefficients can be determined by the trajectories of the particle. The invariants play an important role in the study of a dynamical system, to access the accuracy in numerical simulations and to investigate the classical and quantum integrability of a system. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs) are crucial in regulating T‐cell‐mediated immune responses. Numerous studies have shown that dysfunction or decreased numbers of Tregs may be involved in inflammatory cardiovascular diseases (CVDs) such as atherosclerosis, hypertension, myocardial infarction, myocarditis, cardiomyopathy, valvular heart diseases, heart failure, and abdominal aortic aneurysm. Tregs can help to ameliorate CVDs by suppressing excessive inflammation through various mechanisms, including inhibition of T cells and B cells, inhibition of macrophage‐induced inflammation, inhibition of dendritic cells and foam cell formation, and induction of anti‐inflammatory macrophages. Enhancing or restoring the immunosuppressive activity of Tregs may thus serve as a fundamental immunotherapy to treat hypertension and CVDs. However, the precise molecular mechanisms underlying the Tregs‐induced protection against hypertension and CVDs remain to be investigated. This review focuses on recent advances in our understanding of Tregs subsets and function in CVDs. In addition, we discuss promising strategies for using Tregs through various pharmacological approaches to treat hypertension and CVDs. [ABSTRACT FROM AUTHOR]

The key motive of the current work is the detailed study of charge transport and optoelectronic properties of Benzotrifuran based organic molecules for organic electronic device applications. Density functional theory (DFT) and time dependent‐DFT simulations were executed on studied organic molecules. The absorption characteristics are ascertained and the results are compared with corresponding known experimental results. Frontier molecular orbitals, that is; highest occupied molecular orbital and lowest unoccupied molecular orbital, electron extraction potential, electron affinities, ionization potentials, reorganization energies (Z), and hole extraction potential of all the studied molecules are explored. In contrast, all of the examined organic compounds are with low hole (Zh) and electron (Ze) reorganization energies, making them suitable for use in organic electrical devices. [ABSTRACT FROM AUTHOR]

Starch derived from plants plays an essential role in pharmaceuticals due to its components Amylose and Amylopectin, which form essential granules for drug delivery. Its biocompatibility and cost-effectiveness make it indispensable in pharmaceutical formulations, facilitating controlled drug release and tablet breakdown. The effectiveness and safety of drug formulations are often hindered by challenges such as low solubility and stability. In order to overcome these obstacles, current research is focused on modifying the properties of starch. The goal is to improve its solubility, swelling, erosion, stability, and ability to release drugs. A promising solution that has emerged is ultrasound-based modification. This technique has shown great potential in transforming starch granules, leading to improved solubility, degradability, and control over drug release. Not only is this method efficient and quick, but it also has the added benefit of being eco-friendly. This discussion will explore the mechanisms behind the modification of starch based on ultrasound, delving into both the physical and chemical changes that occur in starch granules. The analysis explores the utilization of modified starch induced by ultrasound in the field of drug delivery, investigating its stability and compatibility with biological systems. By exploring the capabilities and difficulties associated with the use of ultrasound to change starch for the delivery of drugs, we highlighted its potential as a leading and effective methodology. [ABSTRACT FROM AUTHOR]

Chemically modified mandua starch was successfully synthesized and applied to coat mesalamine-loaded matrix tablets. The coating material was an aqueous dispersion of mandua starch modified by sodium trimetaphosphate and sodium tripolyphosphate. To investigate the colon-targeting release competence, chemically modified mandua starch film-coated mesalamine tablets were produced using the wet granulation method followed by dip coating. The effect of the coating on the colon-targeted release of the resultant delivery system was inspected in healthy human volunteers and rabbits using roentgenography. The results show that drug release was controlled when the coating level was 10% w/w. The release percentage in the upper gastric phase (pH 1.2, simulated gastric fluid) was less than 6% and reached up to 59.51% w/w after 14 h in simulated colonic fluid. In addition to in vivo roentgenographic studies in healthy rabbits, human volunteer studies proved the colon targeting efficiency of the formulation. These results clearly demonstrated that chemically modified mandua starch has high effectiveness as a novel aqueous coating material for controlled release or colon targeting. [ABSTRACT FROM AUTHOR]

The present article proposes a novel method to reduce phase noise in a PLL based X-Band source consisting of oscillating and non-oscillating components for the use in Pulse Doppler radar. It also provides phase noise performance stabilization under random vibration. The method consists of improved electrical design and PCB layout, noise filtering technique and passive isolation scheme to suppress vibration-induced noise. Acceleration sensitivity is an important requirement for radars and sensors mounted in unmanned aerial vehicles, aircrafts, missiles and other dynamic platforms. These systems provide superior performance when subjected to severe environmental condition. However, mechanical vibration and acceleration can introduce physical deformation that thereby degrades the frequency source generated signal phase noise. It effects the complete radar system that depends on frequency source performance. The development and testing of a stable X-Band source at 10.64 GHz using indirect method has been carried out which proved that the phase noise is stable both in steady state and under random vibration of 7g magnitude. The study of critical design aspects of test fixture, test object mounting arrangement, investigation on vibration response and performance stabilization along with description of test setup and measurement procedure has been reported. An improvement of around 35-40 dB in phase noise is achieved at close-in offset frequencies. Few challenges and suggestions for the accurate measurement of random vibration testing for frequency sources have also been mentioned. [ABSTRACT FROM AUTHOR]

Background: The research is based on the fertility status of the soil being affected year by year so here is a strategy to save the soil fertility level or soil health by the use of a leguminous cropping system. Methods: A study was conducted during 2018-2021 in the Meerut district of western Uttar Pradesh to evaluate the soil characterization of the rice - pea- sugarcane cropping system. The soil samples were analyzed for various parameters in the laboratory. The status of available NPK in soils and other soil properties like pH, electrical conductivity (EC) and organic carbon (OC) content were assessed. Result: Results reveal that the soils of the study area were neutral to strongly alkaline in reaction and non-saline in nature. Nutrient status regarding to the available nutrient in the surface (0-15 cm) and subsurface (15-30 cm) depth of soil indicate that soils are low in available N and medium in available P and K in surface and subsurface. A positive and significant correlation of NPK with organic matter content was found while significant and negative correlations exist between the soil pH. [ABSTRACT FROM AUTHOR]

AbstractIn this article, the influence of the local thermal non-equilibrium (LTNE) state on free convection in a square cavity filled with fluid-saturated porous medium is investigated numerically. The steady-state flow is induced due to sinusoidal heat distributed on the side walls of the cavity and insulated of the horizontal walls. The coupled flow governing equations are solved numerically by using the finite volume method (FVM) consisting of the SIMPLER (Semi-Implicit Method for Pressure Linked Equation Revised) Algorithm. The numerical simulations of temperature and stream-function contours are carried out for the non-Darcy model. The developed code is validated with existing numerical and present computed results for the case of a square enclosure associated with non-uniform heat source. Then, the present numerical results are analyzed over a range of physical parameters, like periodicity parameter (N≥1), interface heat transfer coefficient (10−2≤H≤102), porosity scaled thermal conductivity ratio (10−2≤γ≤102), with a fixed Rayleigh number (Ra=106), Darcy number (Da=10−4), Prandtl number (Pr = 0.71), and porosity (ε=0.8). To study the impacts of these key parameters on the fluid flow behavior and isotherm patterns of fluid as well as solid phase in the porous-square enclosure. From present numerical experiments that the structure of flow is controlled by multicellular structure with rotating clockwise and anticlockwise directions in the entire results. The flow dynamics are highly affected by the periodicity parameter (N) under LTNE circumstances. The characteristics of the local Nusselt number have the point of inflection and the maximum magnitude of it increases with N. The significant effect of H is found on the heat transfer rate of fluid phase but it is negligible on the heat transfer rate of solid phase. However, the influence of γ is found reverse in nature on the heat transfer rate of fluid as well as solid phase when as compared to the effect of H. [ABSTRACT FROM AUTHOR]

• Proposed-1: Forecast of Solar Cycle 25 using Hybrid CNN-Bidirectional-GRU(CNN-BiGRU). • Proposed-2: Novel Gradient Residual Correction (GRC) model to enhance the proposed-1. • Models are compared with deep-learning traditional models over 4-types of SSN data. • Models' performances are validated based on Friedman ranking for measures. In this study, a hybrid deep-learning(DL) model is proposed, which consists of a Convolution-Neural-Network (CNN) and Bidirectional-Gated-Recurrent-Unit (Bi-GRU) for the prediction of sunspot numbers(SSN) of different frequencies along with novel post-processing techniques of Gradient-Residual-Correction (GRC) to enhance the accuracy of the predictions further. GRC is utilized to reduce the residual present in the forecasted values. The AdaBoost regression model is implemented over the residual obtained from the prediction of training data using a hybrid CNN-BiGRU model with respect to the gradient of the training data points to predict the residual for the test data points. Ultimately, the predicted residual for test data points is summed up with the predicted test data points to achieve the final predictions. The results obtained from the proposed methods are compared with the results obtained from traditional DL models. The validation of the proposed method is carried out based on four performance metrics, namely Root Mean Squared Error(RMSE), Mean Absolute Scaled Error(MASE), Mean Absolute Error(MAE), and Mean Absolute Percentage Error(MAPE). A significant percentage of improvement is observed while using the GRC technique in comparison to all other experimented models for all four variants of SSN data. A maximum improvement of 85.71% has been achieved in comparison to the BiLSTM model over the 13-month smoothed SSN dataset on the basis of MAPE. Friedman Ranking is also performed as a non-parametric statistical test over the results of the performance measures. This model has been utilized for the forecast of solar cycle 25(SC25) over the annual mean of total SSN. It has been observed that the SC25 is expected to reach its peak in the year 2024 with an annual average peak value of 143.641. Comparative analysis of SC25 and the peak of SSN in the ongoing cycle with the previous works are also carried out. [ABSTRACT FROM AUTHOR]

A cascade one‐pot strategy to construct 31 examples of furo‐fused quinoxalines in up to 88% yields has been devised from readily accessible β‐ketothioamides and quinoxalin‐2‐ones in open flask at room temperature under TBHP mediated conditions. Mechanistic studies revealed that the overall reactivity relies on the seamless integration of intermolecular radical coupling and intramolecular cyclization via desulfhydration of C=S bond cleavage. Generation of H2S as the only by‐product makes this process highly attractive. Furthermore, the photophysical behavior of the furo‐fused quinoxalines has also been studied. [ABSTRACT FROM AUTHOR]

Introduction: Hip osteoarthritis is a major public health issue associated with a considerable loss of Health-related Quality of Life (HR-QoL). However, not all patients achieve the same level of functional improvement after Total Hip Arthroplasty (THA) and it is unclear which factors are associated with it. Aim: To determine the functional outcome and QoL in patients who underwent Total Hip Replacement (THR) in an Indian set-up. Materials and Methods: The present prospective cohort study was conducted in the Department of Orthopaedics, Eras Lucknow Medical College and Hospital, Uttar Pradesh, India, from March 2020 to September 2021. A total of 100 patients who underwent THA were included through convenience sampling. Demographic and clinical information, like name, age, gender, Body Mass Index (BMI), duration of symptoms, co-morbidity, Visual Analogue Scale (VAS) score and Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, were noted from the medical records. A single follow-up of all the patients who underwent THA was conducted to assess the complications, functional outcomes and QoL using VAS score (preoperative and postoperative), WOMAC score (preoperative and postoperative), Harris Hip Score (HHS) (postoperative), Short Form-36 (SF-36) health survey (postoperative) questionnaire. The data was analysed using Statistical Package for the Social Sciences (SPSS) software version 25.0. Continuous variables were analysed using the Wilcoxon signed-rank test for paired data. Correlation assessment was done using Pearson's correlation coefficient for continuous factors and Spearman's correlation coefficient for categorical factors. Results: The average age of the patients who underwent THR was 58.90±15.93 years, with a range of 17-95 years. There were 72 males and 28 females. The mean VAS score preoperatively was 7.41±1.20, which decreased significantly to 2.93±0.81 in the postoperative follow-up (p-value<0.001). The mean total WOMAC score improvement was 38.51±10.26 (p-value<0.001). The average postoperative HHS was 73.53±16.16, suggesting a good outcome. The average postoperative SF-36 score was 68.89±12.88. A correlation coefficient of 0.21 (p-value=0.033) suggested that the WOMAC score improvement became higher with an increase in follow-up duration. Patients with postoperative complications had a significantly lower WOMAC improvement (r-value=-0.26, p-value=0.0084). It was observed that the follow-up duration (p-value=0.047) and postoperative complications (p-value=0.016) were significant factors of WOMAC score improvement. Conclusion: Follow-up duration and the presence of postoperative complications were important factors in the functional outcome of patients who underwent THA. Knowledge of these factors can help the clinician to plan the management accordingly while counseling the patients and their relatives regarding any possible adverse outcomes. [ABSTRACT FROM AUTHOR]

The compounds under investigation sought a new approach to synthesis via the Baylis‐Hillman (B−H) and Michael addition reactions. The product formation's legitimacy was tested using a repeat reaction with many different nucleophiles. The additional stability of the product via aromatic π⋅⋅⋅π and C−H⋅⋅⋅π interactions may result in unexpected product formation in diverse reactions undertaken utilizing different starting materials. This study suggests that weak interaction not only provides selectivity during reactions but also modifies the result. [ABSTRACT FROM AUTHOR]

In the current work, we have investigated the charge transport and Non-Linear Optical (NLO) characteristics of oxa[n]circulenes. Density functional theory (DFT) and Time dependent density functional theory (TD-DFT) are used to examine optoelectronic and NLO characteristics. TD-DFT calculations are utilized to simulate the absorption energies. Ionization potential (I.P.), electron affinity (E.A.), the frontier molecular orbitals (FMOs) i.e., Highest occupied molecular orbital (HOMO), Lowest unoccupied molecular orbital (LUMO) and HOMO-LUMO gap (Ege) are calculated for the reported molecules. Nuclear independent chemical shift (NICS) values are generated to find aromatic behavior and stability of oxa[n]circulenes. Along with first and second hyperpolarizabilities, optoelectronic properties are also reported for the designed compounds. [ABSTRACT FROM AUTHOR]

In this work, the impact of extending π -bridge and the adsorption of dyes on the nanocrystalline surface of TiO2 on photovoltaic parameters in dye-sensitized solar cells (DSSCs) has been explored. The dyes comprise phenothiazine (donor), along with benzene, furan, thiophene and selenophene (π -spacers), and cyanoacrylic acid anchoring group (acceptor). The dye geometries, charge transference, and electronic characteristics were investigated using density functional theory (DFT). The impact of extended π -bridge in conjugated systems was explored in dyes along with dyes adsorbed on TiO2 nanocrystalline surface (dye@TiO 2). For the architecture D– π –A in this work, the dyes are effectively adsorbed on the TiO2 nanocrystalline surface. The energy gap between HOMO and LUMO (HLG), ionization potential (IP), reorganization energies (λ) , electron affinity (EA), photovoltaic parameters, adsorption energy (AE), and total density of state (TDOS) are simulated theoretically. Additionally, our investigation illustrates that the studied organic photosensitizer dyes may have improved photovoltaic characteristics and are suitable applicants for efficient charge transportation in organic electronic materials. All the reported dyes are with negative ΔGinj and positive ΔGreg for electron injection and have higher values of JSC, LHE and VOC. The absorption energies range from 358 to 482 nm. Extending π-bridge within the D-π-A arrangement results in bathochromic shift in absorption and narrowing the HLG. Due to presence of H-bonding between oxygen of carboxyl group and a proton on TiO2 surface stabilizes the dye-TiO2 combination. [ABSTRACT FROM AUTHOR]

This study's primary objective is to give a thorough examination of the comparative charge transport and optoelectronic characteristics of all conceivable isomers of benzodithiophene (BDT) and benzodiselenophene (BDSe). Density Functional Theory (DFT) simulations have been performed on all the possible isomers of benzodithiophene (BDT) and benzodiselenophene (BDSe) and results are compared with corresponding experimental known isomers. The absorption energies and HOMO–LUMO energy levels were predicted by Time-Dependent Density Functional Theory (TD–DFT). Electron and hole Reorganization Energies (RE), Hole Extraction Potential (HEP) and Electron Extraction Potential (EEP), Ionization Potentials (IP) and Electron Affinities (EA) of all the isomers are reported. The UV–visible absorption of BDT and BDSe isomers are between 250–417 nm and 290–445 nm respectively. Comparatively, the simulated hole and electron reorganization energy of all the BDT and BDSe isomers have low values and hence expected applications in the field of Organic Optoelectronic Devices. [ABSTRACT FROM AUTHOR]

This paper investigates the projective lag quasi-synchronization by feedback control of a coupled dynamical system with delays and parameter mismatches on arbitrary time domains. Being formulated on time scales, our results are valid simultaneously for continuous- and discrete-time models as well as for any non-standard time domain. Furthermore, the controller design respects the structure of the equations so that we can characterize the stabilization by a limited controller action. Our proofs rely on the unified matrix-measure theory and the generalized Halanay inequality on time scales. We validate our theoretical results with several simulation examples on various time domains. [ABSTRACT FROM AUTHOR]

Introduction: Congenital Hypothyroidism (CH) is defined as the partial or complete loss of thyroid gland function present at birth. During the first 2-3 years of life, thyroid hormone plays a crucial role in brain development. If a baby is born with a deficiency of thyroid hormone (CH) and is not diagnosed and treated appropriately, it can lead to intellectual disability and growth retardation in the affected child. Aim: To screen newborns for CH using Dried Blood Spot (DBS) sampling. Additionally, the study aimed to compare mean TSH values between two comparison groups based on gender, birth weight, gestational age, and type of delivery. Materials and Methods: This cross-sectional study was conducted at Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India, from November 2021 to October 2022. A total of 250 live-birth newborns delivered either by Spontaneous Vaginal Delivery (SVD) or Lower Segment Caesarean Section (LSCS) were included in the study after obtaining written informed consent from their parents. Blood samples were obtained on DBS cards through heel prick in all newborns. TSH levels were assessed using a neonatal TSH sandwich ELISA kit. The cut-off value of TSH to label as screen positive was set at >20 mIU/L. A two-tailed Independent t-test was performed to compare mean TSH values between the two comparison groups based on gender, birth weight, gestational age, and type of delivery. Results: Out of the 250 babies, 137 (54.8%) were male and 113 (45.2%) were female. The gestational age ranged from a minimum of 29 weeks to a maximum of 41 weeks in both male and female babies. TSH levels in male babies ranged from 0.16 mIU/L to 10.27 mIU/L, with a mean value of 3.98±2.16 mIU/L. TSH levels were below 20 mIU/L in all 250 newborns, indicating negative screening results for CH in all the neonates. Conclusion: The results concluded that the serum levels of TSH obtained through heel prick were not statistically significant in both term and preterm newborns, as well as in Normal Birth Weight (NBW) and Low Birth Weight (LBW) newborns. Furthermore, there was no significant difference based on the type of delivery (SVD/LSCS) or the gender of the newborn (male or female). [ABSTRACT FROM AUTHOR]

The time-scales of variability in active M dwarfs can be related to their various physical parameters. Thus, it is important to understand such variability to decipher the physics of these objects. In this study, we have performed the low resolution (∼5.7 Å) spectroscopic monitoring of 83 M dwarfs (M0–M6.5) to study the variability of H α/H β emissions; over the time-scales from ∼0.7 to 2.3 h with a cadence of ∼3–10 min. Data of a sample of another 43 late-type M dwarfs (M3.5–M8.5) from the literature are also included to explore the entire spectral sequence. 53 of the objects in our sample (∼64 per cent) show statistically significant short-term variability in H α. We show that this variability in 38 of them are most likely to be related to the flaring events. We find that the early M dwarfs are less variable despite showing higher activity strengths (LH α/Lbol and LH β/Lbol), which saturates around ∼10−3.8 for M0–M4 types. Using archival photometric light curves from TESS and Kepler/K2 missions, the derived chromospheric emission (H α and H β emission) variability is then explored for any plausible systematics with respect to their rotation phase. The variability indicators clearly show higher variability in late-type M dwarfs (M5–M8.5) with shorter rotation periods (<2 d). For 44 sources, their age has been estimated using StarHorse project and possible correlations with variability have been explored. The possible causes and implications for these behaviours are discussed. [ABSTRACT FROM AUTHOR]

A multi-layer, deep-learning (DL) architecture consisting of stacked Convolutional Long Short Term Memory (sConvLSTM1D) layers is proposed to forecast the sunspot number (SSN) more effectively. The proposed model with optimized hyper-parameters performs efficiently on four kinds of sunspot data with different frequencies of time that are yearly, monthly, daily, and 13-month smoothed provided by the World Data Center-Sunspot Index and Long Term Solar Observation (WDC-SILSO), the Royal Observatory of Belgium (SILSO World Data Center). The model was contrasted with other traditional DL models on different performance metrics, namely root-mean-square error (RMSE), mean-absolute error (MAE), mean-absolute-percentage error (MAPE), and mean-absolute-scaled error (MASE). A non-parametric statistical test has also been carried out to confirm the model's effectiveness. The prediction of the highest yearly mean of total sunspot number (SSN) in Solar Cycle 25 (SC25) has also been performed. The proposed sConvLSTM1D model suggests that the solar cycle exhibits the characteristics of a weak cycle. However, it is anticipated to be stronger than the preceding Solar Cycle 24 (SC24). The year of peak sunspot number will be 2024, as per the prediction, with the peak value of yearly mean sunspot number as 140.84, which is 24.3% higher than the peak value of the yearly mean of total sunspot number, which was 113.3 in the Solar Cycle 24 in the year 2014. [ABSTRACT FROM AUTHOR]

The present work shed light on the structural, electronic, dielectric, and optical properties of MT2 (M = Ba, Hf, Si, Sr and T = F, O) two-dimensional (2D) monolayers using density functional theory. The investigated electronic properties indicate that these 2D monolayer materials exhibit insulating properties. The complex dielectric function is calculated to investigate the optical functions of these monolayer materials. The dielectric and optical calculations are performed for the electric field vectors' orientation parallel (E||x, i.e., in-plane direction) and perpendicular (E||z, i.e., out-of-plane direction) to the plane of these 2D monolayer materials in the energy range 0–60 eV. It is noticed that the dielectric and optical responses of BaF2, HfO2, and SrF2 are shifted toward the lower energy in the ultraviolet (UV) region compared to SiO2. It may be attributed to their larger ionic radii. Due to a similar chemical environment, the studied properties show similar behavior in BaF2 and SrF2. These 2D materials offer high absorption of incident light in a wide energy range of UV region, hence the higher extinction coefficient. The obtained reflection and transmission coefficients in the vacuum ultraviolet (VUV) wavelength region suggest the potential candidature of these materials for VUV optical coatings, such as reflection, bandpass, absorption edge filters, and avoiding solar heating. BaF2 and SrF2 can combine to make low–high refractive index pair material with high refractive index HfO2. The present results indicate that these 2D monolayer materials may be potential candidates for designing optical, photonic, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Herein, we report a one‐pot viable protocol to synthesize tetrasubstituted 2‐aminothiophenes engaging readily accessible α‐enolic dithioesters and abundant fumaronitrile under transition metal‐free conditions at room temperature in open air. The reaction proceeds via successive Michael‐type addition/intramolecular cyclization/isomerization cascades. The added features are benign conditions, exclusive regio‐ and chemoselectivity, excellent atom‐/step‐economy, easy purification, and tolerance of wide range of functional groups of a diverse electronic and steric nature. This protocol not only provided a robust and modular approach to various 2‐aminothiophenes in moderate to excellent yields, but also demonstrated the potential of dithioesters and fumaronitrile in the challenging intermolecular cross‐coupling reactions widening the arsenal of synthetic methods. [ABSTRACT FROM AUTHOR]

Growing human population along the river valleys in hilly terrain particularly on the fluvial sediments poses increasing risk of terrace instability and subsequent failure. Such instability and failure result in frequent loss of settlement, agricultural lands, and often lives. Alaknanda River valley in Uttarakhand comprises many fluvial terrace slopes that accommodate human settlement and hence one such fluvial terrace slope was taken as a case study area. On Feb. 28, 2022, Saari (or Sari) village, situated on the fluvial sequence, witnessed a slope failure collapsing 3 houses but no casualties. The hillslope with a total disturbed area of ∼3889±5.0 m2 and failed material volume of ∼16858±4.3 m3 partially dammed a tributary of Alaknanda River, which passes through the toe of the failed slope. The present study is an attempt to understand the instability that led to such failure because there was no extreme rainfall or earthquake prior to this failure. Pre- and post-failure topography of slope was used to demarcate the detachment and deposition zones. Pre-failure topography was used to perform the Finite Element Method (FEM) based slope stability simulation. In order to evaluate the possible contribution of exposed rockmass in failure, kinematic analysis was also performed. Results revealed the development of displacement pattern, particularly due to anthropogenic loads that must have initiated this failure. Such studies are primary requisites for an effective disaster mitigation in the NW Himalaya where growing human population on fragile hillslopes are at risk. [ABSTRACT FROM AUTHOR]

Natural polymers have attracted significant attention in drug delivery applications due to their biocompatibility, biodegradability, and versatility. However, their surface properties often limit their use as drug delivery vehicles, as they may exhibit poor wettability, weak adhesion, and inadequate drug loading and release. Plasma treatment is a promising surface modification technique that can overcome these limitations by introducing various functional groups onto the natural polymer surface, thus enhancing its physicochemical and biological properties. This review provides a critical overview of recent advances in the plasma modification of natural polymer-based drug delivery systems, with a focus on controllable plasma treatment techniques. The review covers the fundamental principles of plasma generation, process control, and characterization of plasma-treated natural polymer surfaces. It discusses the various applications of plasma-modified natural polymer-based drug delivery systems, including improved biocompatibility, controlled drug release, and targeted drug delivery. The challenges and emerging trends in the field of plasma modification of natural polymer-based drug delivery systems are also highlighted. The review concludes with a discussion of the potential of controllable plasma treatment as a versatile and effective tool for the surface functionalization of natural polymer-based drug delivery systems. [ABSTRACT FROM AUTHOR]

Background: Cervicodynia is one of the most common musculoskeletal symptoms reported by construction workers, particularly those involved in head-load carrying jobs. One of the reasons for this could be accelerated degenerative changes in the cervical spine as a result of continuous stress on it owing to head-load carrying. Apart from carrying a heavy load on the head, frequently have to work in an awkward posture involving "repeated movement of the back and limbs and work above the shoulder during loading on the head and unloading as well as stacking bricks." In response to the continuous stresses on the neck muscles, Cervicodynia is a commonly occurring phenomenon among construction workers, particularly head-load carrying workers. Aims and Objectives: This cross-sectional study aims to determine the association between cervicodynia and head-load carrying in construction site workers in Lucknow. Materials and Methods: A total 68 workers were enrolled in the study and their details were recorded in the questionnaire Pro forma and they were asked to provide their job details. Those workers responding affirmatively to cervicodynia, the intensity, and its distribution along the brachial plexus and vertigo was recorded. Data were recorded on a separate case recording sheet, and statistical analysis was done using SPSS Version 21.0 statistical Analysis Software. The values were represented in number (%) and Mean±SD. The Chi-square test and Student's "t" test was used. The level of significance was P<0.05. Results: Out of 68 workers, 57.4% were male, whereas 42.6% were female with a mean age of 32.15 years. The overall complaints of neck pain were 55.9%. Workers with complaints of neck pain carry significantly higher weight per round, carry weight for significantly longer duration, and cover significantly longer distance with weight. Conclusion: It can be concluded that cervicodynia is a common occurrence among construction workers, particularly, head-load carriers. Although univariate analysis highlighted the role of occupational factors in the occurrence of neck pain, on multivariate assessment, only age emerged as an independent predictor. [ABSTRACT FROM AUTHOR]

Background: Numerous unfavourable outcomes for newborns are linked to foetal and neonatal acidemia.1-7 Low Apgar scores, respiratory distress syndrome, hypoxic-ischemic encephalopathy, convulsions, intraventricular haemorrhage, sepsis, and death are some of these outcomes.1-7 Understanding the mechanisms underlying these results and the period of the injury can have significant medico-legal repercussions. Objectives: 1. To assess the relationship between umbilical cord blood (arterial andvenous) analyses and perinatal risk factors in pregnancy. 2. To assess the relationship between umbilical cord blood pH and Apgar score in high risk group of pregnancy. Material & Methods: Study Design: Hospital based prospective observational study. Study area: Department of Obstetrics & Gynecology, in a tertiary care teaching hospital. Study Period: Jan 2022 - Dec. 2022. Study population: All pregnant ladies who presented in labor to maternity ward, in a tertiary care teaching hospital. Sample size: Study consisted a total of 192 subjects. 192 pregnant ladies who presented to labor ward, in a tertiary care teaching hospital. At the time of admission, they were assigned to high or low risk group according to whether or not they had any perinatal risk factors. High risk pregnancy is defined as the mother who is at risk to deliver a neonate with birth asphyxia according to the definition by American Academy of Pediatrics. All normal vaginal and cesarean section deliveries included in this study were chosen in accordance with this definition. Sampling Technique: Simple Random technique. Results: Apart from the study proving the statistical difference in the high risk and low risk groups in various cord blood parameters; it also compared the cord blood pH with the Apgar score to find any correlation between them. Pearson correlation was used to define the correlation. In the low risk group, neither arterial nor venous pH was statistically related to Apgar score. In high risk group, a statistically significant correlation was established between Apgar at 1 minute and the arterial and venous pH. Conclusion: The results of this study indicate that umbilical cord blood analysis might be useful predictors of fetal asphyxia at delivery. Our study highlights a correlation between the presence of perinatal risk factors and umbilical cord pH in high-risk mothers. So we recommend assessing the umbilical cord pH in any mother who has a perinatal risk factor in her history or physical examination. Their potential role as a tool for predicting the prenatal outcomes should be evaluated in subsequent studies. [ABSTRACT FROM AUTHOR]

Floods are becoming more frequent in Himalaya, particularly in the NW Himalaya, and have been related to the increasing impact of changing climate. Uttarakhand in the NW Himalaya has witnessed 2 major flood events in the last decade that killed more than 6000 people. This study is an attempt to explore the impact of potential flood on a riverbank slope in Uttarakhand, NW Himalaya. The response of this riverbank slope during extreme rainfall is also explored in terms of stability and debris flow runout. Therefore, we evaluated the riverbank slope stability and the runout extent of its material to understand the slope response during extreme rainfall. Flood simulation was also performed to determine the potential flood impact on the riverbank slope. Results revealed that the slope material at the exposed fluvial sequence and slope toe might displace forward ~0.12–0.4 m. The potential debris flow from the slope may impact the retaining wall supporting the slope with a pressure up to 150 k Pa. The potential flood may strike the riverbank with a velocity and stream power of 10 ± 2 m/s and 0.2 ± 0.1 M N/m-s, respectively, which is about three times higher than the approximated resistance of the retaining wall. [ABSTRACT FROM AUTHOR]

• We formulated a new class of piecewise impulsive dynamic systems on arbitrary time domain by using the time scales theory. • Study the existence of solutions via fixed point theorems. Also establish the stability results of the considered problem. • Provide some necessary and sufficient conditions for the controllability of the piecewise linear system. • Develop a new class of control function and establish sufficient conditions for the controllability of nonlinear systems. • Some numerical simulations for different time domains are given to verify the proposed theoretical results. The main objective of this article is to establish the existence of solutions, stability, and controllability results for piecewise nonlinear impulsive dynamic systems on an arbitrary time domain. Using the Banach fixed point theorem, we prove the existence of a unique solution while by applying Schauder's fixed point theorem, we prove the existence of at least one solution. Further, we establish the controllability results by converting the controllability problem into a fixed point problem of an operator equation in some suitable function space. Mainly, we used the fixed point theorems, Gramian type matrices, functional analysis, and time scales theory to establish these results. Since the problem is formulated by using the theory of time scales, therefore, the obtained results are true for the continuous-time domain, discrete-time domain, as well as any combination of these two, which shows that the obtained results are non-trivial and generalize the existing ones. In the last, we have given a simulated example for two different time domains to verify the obtained analytical results. [ABSTRACT FROM AUTHOR]

Efficient termination of cover crops is an important component of cover crop management. Information on termination efficiency can help in devising management plans but estimating herbicide efficacy is a tedious task and potential remote sensing technologies and vegetative indices (VIs) have not been explored for this purpose. This study was designed to evaluate potential herbicide options for the termination of wheat (Triticum aestivum L.), cereal rye (Secale cereale L.), hairy vetch (Vicia villosa Roth.), and rapeseed (Brassica napus L.), and to correlate different VIs with visible termination efficiency. Nine herbicides and one roller-crimping treatment were applied to each cover crop. Among different herbicides used, glyphosate, glyphosate + glufosinate, paraquat, and paraquat + metribuzin provided more than 95% termination for both wheat and cereal rye 28 days after treatment (DAT). For hairy vetch, 2,4-D + glufosinate and glyphosate + glufosinate, resulted in 99 and 98% termination efficiency, respectively, followed by 2,4-D + glyphosate and paraquat with 92% termination efficiency 28 DAT. No herbicide provided more than 90% termination of rapeseed and highest control was provided by paraquat (86%), 2,4-D + glufosinate (85%), and 2,4-D + glyphosate (85%). Roller-crimping (without herbicide application) did not provide effective termination of any cover crop with 41, 61, 49, and 43% termination for wheat, cereal rye, hairy vetch, and rapeseed, respectively. Among the VIs, Green Leaf Index had the highest Pearson correlation coefficient for wheat (r = -0.786, p = <0.0001) and cereal rye (r = -0.804, p = <0.0001) with visible termination efficiency rating. Whereas for rapeseed, the Normalized Difference Vegetation Index (NDVI) had the highest correlation coefficient (r = -0.655, p = <0.0001). The study highlighted the need for tankmixing 2,4-D or glufosinate with glyphosate for termination instead of blanket application of glyphosate alone for all crops including rapeseed and other broadleaf cover crops. [ABSTRACT FROM AUTHOR]

Lithium (2 wt.%)-doped cadmium oxide (CdO:Li) film was grown on a glass substrate via a sol-gel processed screen-printing set-up. Through X-ray diffraction, it was demonstrated that the CdO:Li film exhibits reflections from the (111), (200), (220), (311), and (222) CdO cubic phase planes. The SEM image showed irregularly shaped, interconnected, and agglomerated grains on the entire film. The optical diffuse reflection study revealed that the film has a direct transition of the band gap at 2.50 eV. The refractive index of the film varies with photon energy and gains maximum value (~2.3) at 1.5 eV. The electrical attributes of the film were inspected by Hall measurement. It was noticed that the film conveyed n-type conductivity with low resistivity of the order of 10–3 Ω·cm. [ABSTRACT FROM AUTHOR]

Background Dengue fever (DF) is a common viral disease, clinical manifestations of which vary from influenza-like illness (DF) to life-threatening dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS). The aim of this article was to study the clinical profile of DF in young adults. Material and Methods This was an observational study conducted in the department of medicine over a period of 2 years (January 1, 2013—December 31, 2014). Patients aged between 18 and 30 years with serology proven (nonstructural protein 1 [NS1]/dengue immunoglobulin M [IgM]) DF were included in this study. The clinical and laboratory data was recorded and analyzed. Results Out of 418 cases, the incidence of DF, DHF, and DSS was 87.32, 7.66, and 5.02%, respectively. The most common presentations were fever (99.76%) followed by vomiting (29.43%), pain abdomen (17.94%), myalgias (13.16%), petechial rash (12.92%), and bleeding (10.29%). Dengue NS1 and IgM antibodies were positive in 87.3% and 88.12% of the patients, respectively. Ascites, splenomegaly, hepatomegaly, pleural effusion, gall bladder wall edema, and pericardial effusion were present in 8.13, 6.94, 6.70, 5.98, 2.63, and 0.72% of the patients, respectively. Complications included bleeding (10.29%), acute respiratory distress syndrome (1.67%), myocarditis (1.44%), seizures (1.44%), hemarthrosis (0.24%), and encephalopathy (0.24%). The mortality rate was 3.35% with death of 14 patients. Shock, bleeding, and elevated serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase levels predicted adverse outcome. Conclusion DF can present with a plethora of clinical manifestations in endemic areas. Adverse outcome is more likely if patients have elevated SGOT levels, shock, and bleeding. Continuous seroepidemiological surveillance is essential to control outbreak and minimize morbidity and mortality. [ABSTRACT FROM AUTHOR]

This article describes studies on the design, synthesis, and biological evaluation of pyrazole‐containing β‐amino carbonyl compounds (5a–5q) as DPP‐4 inhibitors and anti‐diabetic agents. In contrast, mannich reactions went smoothly with bismuth nitrate (Bi (NO3)3) catalyst in the presence of ethanol and produced pyrazole‐containing β‐amino carbonyl compounds in good yield. Molecular docking studies of designed derivatives with DPP‐4 enzyme (PDB: 2OLE), compounds 5d, 5h, 5j, and 5k showed excellent interaction. 3D QSAR and pharmacophoric model studies were also carried out. ADMET parameters, pharmacokinetic properties, and in vivo toxicity studies further confirmed that all the designed compounds were found to have good bioavailability and were less toxic. Further, these compounds were evaluated as enzyme‐based in vitro DPP‐4 inhibitory activity, and 5d, 5h, 5i, 5j, and 5k exhibited IC50 toward DPP‐4 enzyme of 10.52, 10.41, 5.55, 4.16, and 7.5 nM, respectively. The most potent compound, 5j, was further selected for in vivo anti‐diabetic activity using an STZ‐induced diabetic mice model, and 5j showed a significant diabetic control effect. [ABSTRACT FROM AUTHOR]

Our changing climate will likely have serious implications on agriculture production through its effects on food and feed crop yield and quality, forage and livestock production, and pest dynamics, including troublesome weed control. With regards to weeds, climatic variables control many plant physiology functions that impact flowering, fruiting, and seed dormancy; therefore, an altered climate can result in a weed species composition shift within agro-ecosystems. Weed species will likely adapt to a changing climate due to their high phenotypic plasticity and vast genetic diversity. Higher temperatures and CO2 concentrations, and altered moisture conditions, not only affect the growth of weeds, but also impact the effectiveness of herbicides in controlling weeds. Therefore, weed biology, growth characteristics, and their management are predicted to be affected greatly by changing climatic conditions. This manuscript attempted to compile the available information on general principles of weed response to changing climatic conditions, including elevated CO2 and temperature under diverse rainfall patterns and drought. Likewise, we have also attempted to highlight the effect of soil moisture dynamics on the efficacy of various herbicides under diverse agro-ecosystems. [ABSTRACT FROM AUTHOR]

In present report on Zn doped (5%) CdO thick film is synthesized on to the glass substrate (pre‐cleaned) via sol–gel screen printing process. The synthesized sintered Zn:CdO film are then characterized via XRD, SEM, EDX, UV–vis spectroscopy, PL spectroscopy, and dark conductivity measurement examinations. The XRD examination of sintered film informs the polycrystalline nature and authenticates that Zn:CdO film holds the cubic crystalline structure. SEM examination dispenses the information on morphology of Zn:CdO film. The EDX examination supports the existence of Cd, O, and Zn in the sintered film. The UV–vis spectroscopy via reflectance mode substantiates the direct transition of band gap with a value of 2.60 eV. PL spectra of the sintered film manifest a strong near band edge emission located around 500 nm. The Arrhenius plot (log σDC vs 1000/T) attests the semiconducting nature for the sintered film. [ABSTRACT FROM AUTHOR]

Pollen grains represent the male gametes of seed plants and their viability is critical for sexual reproduction in the plant life cycle. Palynology and viability studies have traditionally been used to address a range of botanical, ecological and geological questions, but recent work has revealed the importance of pollen viability in invasion biology as well. Here, we report an efficient visualmethod for assessing the viability of pollen using digital holographic microscopy (DHM). Imaging data reveal that quantitative phase information provided by the technique can be correlated with viability as indicated by the outcome of the colorimetric test.We successfully test this method on pollen grains of Lantana camara, a well-known alien invasive plant in the tropical world. Our results show that pollen viability may be assessed accurately without the usual staining procedure and suggest potential applications of the DHM methodology to a number of emerging areas in plant science. [ABSTRACT FROM AUTHOR]

This paper concerns with the existence, uniqueness, Ulam's Hyer (UH) stability and total controllability results for the Hilfer fractional switched impulsive systems in finite-dimensional spaces. Mainly, this paper can be divided into three parts. In the first part, we examine the existence of a unique solution. In the second part, we establish the UH stability results, and in the third part, we study the total controllability results. The main outcomes are acquired by utilising the nonlinear analysis, fractional calculus, Mittag–Leffler function and Banach contraction principle. Finally, we have given two examples to validate the obtained analytical results. [ABSTRACT FROM AUTHOR]

Context: The anthelminthic effect of Ocimum species (Lamiaceae) has been reported, however, its anti-filarial effect has not been explored to date. Objective: This study evaluates the effect of Ocimum sanctum L. (OS) against lymphatic filarial parasites. Material and methods: The ethanol extract of OS (EOS) leaves was tested for anti-filarial activity against Setaria cervi. Equal size and number (n=10) of adult female S. cervi worms were incubated in 125, 250 or 375 lg/mL EOS extract for 6 h at 37 °C. The OS bioactive components were identified by UPLC-ESI-MS/MS and subjected to docking and molecular dynamics (MD) simulation against filarial antioxidant proteins. Results: The EOS significantly inhibited the motility of adult female S. cervi after 6 h of incubation. The motility was found to be reduced by 53.7% in 375 mg/mL and 43.8% in 250 mg/mL EOS after 6 h of treatment. The UPLC-ESI-MS/MS analysis of ethanol extract of O. sanctum revealed the presence of 13 bioactive compounds. The docking analysis showed eight OS bioactive compounds to have high binding affinity (> 4.8 kcal/mol) towards antioxidant proteins of filarial parasites. Additionally, MD simulation studies showed significant impact of (RMSD ≤ 10 Å) chlorogenic acid, luteolin and ursolic acid on filarial antioxidant enzymes/proteins. To our knowledge, this is the first report of the anti-filarial activity of Ocimum sanctum. Discussion and conclusions: The effect of EOS and OS bioactive components on human filarial parasites can be further evaluated for the development of new anti-filarial formulations. [ABSTRACT FROM AUTHOR]

Organic polymers have found diverse applications in the industrial and scientific world. One such application is using chitosan-based electrochemical sensors, which have gained rapid popularity due to their unique properties. To further enhance the material's porosity and adsorption capacity, the incorporation of a surfactant into the film has been explored. This study focuses on a rarely investigated combination of fungi-derived chitosan and cationic surfactant N-Cetyl- N , N , N -trimethyl-ammonium bromide (CTAB). The resultant composite was transformed into a thin film on the surface of a graphite electrode, by drop casting method, followed by curing at 65 °C hot air. The low-cost sensor thus obtained was characterized by electrochemical studies, and surface study techniques including AFM, SEM, and XPS. The results showed the properties of the film were strongly governed by the ratio of components in the composite. Under optimal conditions, the affinity for composite film increased 3 to 4 folds for Pb and Cd. The developed electrochemical sensors had a limit of detection of 0.317 μM and 0.572 μM for Pb and Cd respectively. The linear range of detection was found to be 1 × 10−6 M to 1.2 × 10−4 M for Pb (II) and 2 × 10−6 M to 1.4 × 10−4 M for Cd (II). [Display omitted] • The critical concentration of 1.35 mM of CTAB can enhance the metal affinity of Chitosan. • The Chitosan-CTAB composite showed 3 to 4 times higher affinity for Pb (II) and Cd (II). • The composite showed a porous structure, with active amine and hydroxyl groups involved in metal binding. • The limit of detection for Pb+2 and Cd+2 was found to be 0.317 μM and 0.572 μM respectively. [ABSTRACT FROM AUTHOR]

Organic polymers have found diverse applications in the industrial and scientific world. One such application is using chitosan-based electrochemical sensors, which have gained rapid popularity due to their unique properties. To further enhance the material's porosity and adsorption capacity, the incorporation of a surfactant into the film has been explored. This study focuses on a rarely investigated combination of fungi-derived chitosan and cationic surfactant N-Cetyl- N , N , N -trimethyl-ammonium bromide (CTAB). The resultant composite was transformed into a thin film on the surface of a graphite electrode, by drop casting method, followed by curing at 65 °C hot air. The low-cost sensor thus obtained was characterized by electrochemical studies, and surface study techniques including AFM, SEM, and XPS. The results showed the properties of the film were strongly governed by the ratio of components in the composite. Under optimal conditions, the affinity for composite film increased 3 to 4 folds for Pb and Cd. The developed electrochemical sensors had a limit of detection of 0.317 μM and 0.572 μM for Pb and Cd respectively. The linear range of detection was found to be 1 × 10−6 M to 1.2 × 10−4 M for Pb (II) and 2 × 10−6 M to 1.4 × 10−4 M for Cd (II). [Display omitted] • The critical concentration of 1.35 mM of CTAB can enhance the metal affinity of Chitosan. • The Chitosan-CTAB composite showed 3 to 4 times higher affinity for Pb (II) and Cd (II). • The composite showed a porous structure, with active amine and hydroxyl groups involved in metal binding. • The limit of detection for Pb+2 and Cd+2 was found to be 0.317 μM and 0.572 μM respectively. [ABSTRACT FROM AUTHOR]

Here, we studied the physical properties of atomic oxygen-doped two-dimensional (2D) MgF 2 monolayer using density functional theory. The undoped MgF 2 exhibits an insulating behavior. However, it shows a small amount of incident light absorption in the visible region when an F-atom is substitutional doped with an oxygen (O) atom. Further, the increasing oxygen concentration shows an enhanced optical absorption of light in the visible spectrum. Hence, it can be used as an absorption band pass/stop filter. The absorption spectrum is consistent with the calculated extinction coefficient. The increased absorption shows the improved conductivity of doped MgF 2. Moreover, the dielectric constant and refractive index increase with increasing O-doping concentration. Its refractive index enhances more than that of silicon (3.9). The increased O-doping also enhances the reflection of light in the microwave to the infrared region, which is justified by the transmission spectrum. The energy losses also increase with increasing O-concentration. These losses show the existence of plasma resonances. The dielectric and optical responses show that it behaves like a high-k dielectric material for large O-doping concentrations. The discussion above indicates that the O-doped 2D MgF 2 monolayer is an excellent electronic and dielectric material for electronic, optical, and optoelectronic applications. • The O-doping-induced tunable optoelectronic response of the 2D MgF 2 is investigated. • Highly O-doped MgF 2 exhibits a feature similar to that of a high-k dielectric material. • The doping effects are significant only in the microwave to the visible region. • The doping significantly enhances the absorption of light for low energies. • These findings show the potential candidature of O-doped MgF 2 for optoelectronics. [ABSTRACT FROM AUTHOR]

Here, we report the synthesis of the WS2 nanorods (NRs) using an eco-friendly and facile hydrothermal method for an acetone-sensing application. This study explores the acetone gas-sensing characteristics of the WS2 nanorod sensor for 5, 10, and 15 ppm concentrations at 25 °C, 50 °C, 75 °C, and 100 °C. The WS2 nanorod sensor shows the highest sensitivity of 94.5% at 100 °C for the 15 ppm acetone concentration. The WS2 nanorod sensor also reveals the outstanding selectivity of acetone compared to other gases, such as ammonia, ethanol, acetaldehyde, methanol, and xylene at 100 °C with a 15 ppm concentration. The estimated selectivity coefficient indicates that the selectivity of the WS2 nanorod acetone sensor is 7.1, 4.5, 3.7, 2.9, and 2.0 times higher than xylene, acetaldehyde, ammonia, methanol, and ethanol, respectively. In addition, the WS2 nanorod sensor also divulges remarkable stability of 98.5% during the 20 days of study. Therefore, it is concluded that the WS2 nanorod can be an excellent nanomaterial for developing acetone sensors for monitoring work/public places. [ABSTRACT FROM AUTHOR]