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The aim of this manuscript is to design and analyze a hybrid stable numerical algorithm for generalized fractional derivative (GFD) defined in Caputo sense D0,Z,ωα z m on non-uniform grid points in the temporal direction. An efficient and hybrid high order discretization is proposed for GFD by incorporating a (3 -- α)-th order approximation using the moving refinement grid method for the initial interval in the temporal direction. The physical applications of the developed high order approximation are employed to design a hybrid numerical algorithm to determine the solution of the generalized time-fractional telegraph equation (GTFTE) and the generalized time-fractional stochastic telegraph equation (GTFSTE). The proposed numerical techniques are subjected to rigorous error analysis and a thorough investigation of theoretical results i.e. solvability, unconditional stability, convergence analysis, and comparative study are conducted with the existing scheme (Kumar et al. in Numer Methods Partial Differ Equ 35(3):1164-1183, 2019). Several test functions are utilized to verify that second-order convergence is attained in time which is higher than the order of convergence produced by the existing scheme (Kumar et al. 2019). In spatial direction, fourth-order convergence is obtained utilising the compact finite difference methods in spatial approximation on uniform meshes. A reduced first-order convergence in the temporal direction is reported for the GTF-STE model. Further, certain scaling and weight functions are used to show cast the impact of scaling and weight functions in the GFD. [ABSTRACT FROM AUTHOR]

The power conversion efficiency of all-inorganic Sb2S3-on-Si two-terminal (2-T) monolithically integrated and four-terminal (4-T) mechanically stacked tandem solar cells are investigated. A one-dimensional solar cell capacitance simulator (SCAPS-1D) has been used to simulate the stand-alone antimony trisulfide (Sb2S3) top sub-cell, silicon (Si) bottom sub-cell, 2-T monolithic, and 4-T mechanically stacked tandem solar cells. The stand-alone sub-cells are optimized by extensive studies, including interface defects density, bulk defects density, absorber layer thickness, and series resistance. The power conversion efficiency (PCE) of simulated stand-alone sub-cells is compared and verified with the existing literature. A current matching condition is established to characterize the 2-T monolithic Sb2S3-on-Si tandem cell. A filtered spectrum has been utilized for bottom sub-cell measurement in the tandem solar cells. The best-simulated PCE of Sb2S3-on-Si 2-T monolithic and 4-T tandem cells is 30.22% and 29.30%, respectively. The simulation results presented in this paper open an opportunity for the scientific community to consider Sb2S3 as a potential top sub-cell material in Sb2S3-on-Si tandem solar cells with high PCE. [ABSTRACT FROM AUTHOR]

A new hetero-structure of n-TiO2/p-WS2/p-Cu2O is proposed as a potential candidate for solar energy generation using tungsten disulfide (WS2) as an absorber layer. The proposed device performance is simulated by employing a one-dimensional solar cell capacitance simulator (SCAPS-1D). The numerical simulation studies compared the performances of n-TiO2/p-Cu2O, n-TiO2/p-WS2/p-Cu2O, and n-TiO2/p-WS2 hetero-structures based on various physical parameters like interface defects density, bulk defects density, absorber layer thickness, series resistance, shunt resistance, and operating temperature. In our simulation investigations, we found that interface defects pose a formidable impact on heterojunction devices. Interface defects closer to the front surface severely deteriorate the performances than the back surface. The bandgap of the absorber layer influences the performances of the solar cells. A closer comparison between n-TiO2/p-Cu2O and n-TiO2/p-WS2 heterojunction solar cells (HJSCs) revealed that the latter (n-TiO2/p-WS2) has nearly 182% better performance than the former (n-TiO2/p-Cu2O) devices. Additionally, the performance of the n-TiO2/p-WS2 solar cell is further boosted by ~ 139% in the presence of a hole transport layer of p-Cu2O. The best-simulated efficiency of the proposed new hetero-structure (n-TiO2/p-WS2/p-Cu2O) solar cell is 28.86%. Moreover, these optimized physical parameters may shed light on "easy to apply" new path for fabrication of a non-toxic, environment-friendly, and highly efficient novel thin-film heterojunction (n-TiO2/p-WS2/p-Cu2O) solar cell. [ABSTRACT FROM AUTHOR]

The Indian summer monsoon rainfall (ISMR) exhibits significant variability, affecting the food and water security of the densely populated Indian subcontinent. The two dominant spatial modes of ISMR variability are associated with the El Niño Southern Oscillation (ENSO) and the strength of the semi-permanent monsoon trough along with related variability in monsoon depressions, respectively. Although the robust teleconnection between ENSO and ISMR has been well established for several decades, the major drivers leading to the time-varying relationship between ENSO and ISMR patterns across different regions of the country are not well understood. Our analysis shows a consistent increase from a moderate to substantially strong teleconnection strength between ENSO and ISMR from 1901 to 1940. This strengthened relationship remained stable and strong between 1941 and 1980. However, in the recent period from 1981 to 2018 the teleconnection decreased consistently again to a moderate strength. We find that the ENSO–ISMR relationship exhibits distinct regional variability with time-varying relationship over the north, central, and south India. Specifically, the teleconnection displays an increasing relationship for north India, a decreasing relationship for central India and a consistent relationship for south India. Warm SST anomalies over the eastern Pacific Ocean correspond to an overall decrease in the ISMR, while warm SST anomalies over the Indian Ocean corresponds to a decrease in rainfall over the north and increase over the south of India. The central Indian region experienced the most substantial variation in the ENSO–ISMR relationship. This variation corresponds to the variability of the monsoon trough and depressions, strongly influenced by the Pacific Decadal Oscillation and North Atlantic Oscillation, which regulate the relative dominance of the two spatial modes of ISMR. By applying the PCA-Biplot technique, our study highlights the significant impacts of various climate drivers on the two dominant spatial modes of ISMR which account for the evolving nature of the ENSO–ISMR relationship. [ABSTRACT FROM AUTHOR]

In this work, our motivation is to design an impressive new numerical approximation on non-uniform grid points for the Caputo fractional derivative in time 0 C D t α with the order α ∈ (1,2). An adaptive high-order stable implicit difference scheme is developed for the time-fractional diffusion wave equations (TFDWEs) by using estimation of order O (N t α - 5) for the Caputo derivative in the time domain on non-uniform mesh and well-known second-order central difference approximation for estimating the spatial derivative on a uniform mesh. The designed algorithm allows one to build adaptive nature where the scheme is adjusted according to the behaviour of α in order to keep the numerical errors very small and converge to the solution very fast as compared to the previously investigated scheme. We rigorously analyze the local truncation errors, unconditional stability of the proposed method, and its convergence of (5 − α)-th order in time and second-order in space for all values of α ∈ (1,2). A reduced order technique is implemented by using moving mesh refinement and assemble with the derived scheme in order to improve the temporal accuracy at several starting time levels. Furthermore, the numerical stability of the derived adaptive scheme is verified by imposing random external noises. Some numerical tests are given to show that the numerical results are consistent with the theoretical results. [ABSTRACT FROM AUTHOR]

A rigorous exploration of microbial diversity has revealed its presence on Earth, deep oceans, and vast space. The presence of microbial life in diverse environmental conditions, ranging from moderate to extreme temperature, pH, salinity, oxygen, radiations, and altitudes, has provided the necessary impetus to search for them by extending the limits of their habitats. Microbiology started as a distinct science in the mid-nineteenth century and has provided inputs for the betterment of mankind during the last 150 years. As beneficial microbes are assets and pathogens are detrimental, studying both have its own merits. Scientists are nowadays working on illustrating the microbial dynamics in Earth's subsurface, deep sea, and polar regions. In addition to studying the role of microbes in the environment, the microbe-host interactions in humans, animals and plants are also unearthing newer insights that can help us to improve the health of the host by modulating the microbiota. Microbes have the potential to remediate persistent organic pollutants. Antimicrobial resistance which is a serious concern can also be tackled only after monitoring the spread of resistant microbes using disciplines of genomics and metagenomics The cognizance of microbiology has reached the top of the world. Space Missions are now looking for signs of life on the planets (specifically Mars), the Moon and beyond them. Among the most potent pieces of evidence to support the existence of life is to look for microbial, plant, and animal fossils. There is also an urgent need to deliberate and communicate these findings to layman and policymakers that would help them to take an adequate decision for better health and the environment around us. Here, we present a glimpse of recent advancements by scientists from around the world, exploring and exploiting microbial diversity. [ABSTRACT FROM AUTHOR]

Climatologically, the frequency of tropical cyclones (TCs) in the Bay of Bengal (BoB) is higher relative to that over the Arabian Sea (ARB). However, recent years exhibit a greater number of TCs forming in the ARB than in the BoB. During the study period (1982–2019), a significant increasing trend in the intensity, frequency, and duration of cyclonic storms (CS) and very severe CS (VSCS) is observed over the ARB. There is a 52% increase in the frequency of CS during the recent epoch (2001–2019) in the ARB, while there is a decrease of 8% in the BoB. Over the ARB, increment in CS duration is 80% and VSCS is almost threefold in the recent epoch as compared to the past epoch (1982–2000). Also, lifetime maximum intensity and accumulated cyclone energy have increased over the ARB implying an increase in the strength of TCs. The increase in TC duration over the ARB is prominent during May, June, and October and a decrease over the BoB is noted during November. The increase in the duration of TCs in the ARB is associated with an increase in mid-level relative humidity and column averaged (950-150 hPa) moist static energy, which is significantly correlated to an increase in sea surface temperatures and tropical cyclone heat potential in the basin. In the recent epoch, TC genesis is observed at lower latitudes (< 8° N), which is another factor contributing to longer durations of TCs. This increases the probability of TC intensification with the support from other favourable environmental parameters. Significant changes in TC tracks are also noted in May, June, and October due to changes in steering currents. [ABSTRACT FROM AUTHOR]

Author Correction: Regional and temporal variability of Indian summer monsoon rainfall in relation to El Niño southern oscillation Introduction Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-023-38730-5, published online 04 August 2023 In the original version of this Article, Panini Dasgupta and J. S. Saranya were incorrectly affiliated with "Seoul National University, Seoul, South Korea". The original article can be found online at https://doi.org/10.1038/s41598-023-38730-5. [Extracted from the article]

Cyclone Fani, in April 2019, was the strongest pre-monsoon cyclone to form in the Bay of Bengal after 1994. It underwent rapid intensification and intensified quickly to an extremely severe cyclone. It maintained a wind speed of ≥ 51 m s−1 (≥ 100 knots) for a record time period of 36 h. The total lifespan of the cyclone was double than the climatological lifespan. Also, the duration of the cyclone in its extremely severe phase and the accumulated cyclone energy were significantly larger than the climatological records for the pre-monsoon season. In the current study, we investigate the ocean-atmospheric conditions that led to its genesis, rapid intensification and long lifespan. Our analysis shows that the Madden Julian Oscillation and anomalous high sea surface temperatures provided conducive dynamic and thermodynamic conditions for the genesis of cyclone Fani, despite forming very close to the equator where cyclogenesis is generally unlikely. Further, favourable ocean subsurface conditions and the presence of a warm core eddy in the region led to its rapid intensification to an extremely severe cyclone. A large area of warm ocean surface and subsurface temperatures aided the cyclone to maintain very high wind speed for a record time period. The vital role of the ocean surface and the subsurface in the genesis and the intensification highlights the need to efficiently incorporate ocean initial conditions (surface and sub-surface) and ocean–atmosphere coupling in the operational cyclone forecasting framework. [ABSTRACT FROM AUTHOR]

The present study deals with a computational investigation on the role of dithiocarbamate (DTC) anions in the stabilization of σ-aromatic trinuclear mono-cationic metal clusters (M = Cu, Ag and Au). Electrostatic potential, aromaticity, binding energy, thermodynamical parameters and nature of bonding are estimated. Nucleus independent chemical shifts (NICS) and their variants such as NICStotal and FiPC-NICS are employed to calculate aromaticity. The nature of bonding is assessed by the quantum theory of atoms-in-molecules (QT-AIM) and NBO methods. The charge density map in the complex has been assessed by molecular electrostatic potential analysis. Comparison of complexation properties of DTC ligand to common monodentate ligands (pyrazolates, NHC, pyridine, furan and isoxazole) explored in past reveal that DTC anions are more efficient in stabilizing metal complexes. Synopsis. A computational approach is undertaken to investigate complexation properties of dithiocarbamate (DTC) anions with electron-deficient M3+ (M = Cu, Ag & Au) clusters. DTC ligands are found to be efficient chelators as compared to commonly used monodentate ligands to bind and stabilize such unstable trinuclear mono-cationic metal clusters [ABSTRACT FROM AUTHOR]