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Based on the geometric phases of Bloch electrons, we propose a scheme for the unambiguous spatial partitioning of charge in matter from first-principles, derivable directly from the Kohn–Sham states. Generalizing the fact that geometric phases acquired by electrons, due to the evolution of their crystal momentum k→in any arbitrary direction throughout the Brillouin zone (BZ), render the location of their spatial localization with net minimum spread along the direction in real space reciprocal to that of the evolution of k→, we find that the total charge can be meaningfully distributed into centers of a class of correlated hermaphrodite Wannier functions simultaneously contributed by electrons with their crystal momenta evolving linearly independently through each unique k→across the BZ. The resultant map of charge centers readily renders not only the qualitative nature of interatomic as well as intra-atomic hybridization of electrons but also unbiased quantitative estimates of electrons that can be associated with atoms or shared between them, as demonstrated in a selected variety of isolated and periodic systems with varying degrees of sharing of valence electrons among atoms, including variants of multicentered bonds.

Multi drug resistance (MDR) in breast carcinoma still poses a significant impairment to successful chemotherapy. As the arsenal of anticancer agents increases with improved preclinical methods, the growth of therapeutic drug combinations is now unprecedented. The malignancies addressed by mono drugs often fail to limit cancer progression, resulting in resistant cancer, thereby offering combinatorial therapies a terrific edge over monodrug regimes. However, the selection of drug combinations required enough preliminary evidence for their synergistic effect. The fundamental mechanisms of MDR to chemotherapeutics are associated with the overexpression of membrane efflux pumps, alternations in drug targets, and increased drug metabolism. Unfortunately, it is very difficult for drugs to overcome resistance produced on their own or by another different drug action. In this context, herein, we report a simple delivery system for coencapsulation and intracellular codelivery of dual-drug thymoquinone (TQ) and doxorubicin (DOX) to resensitize DOX-resistant MDA MB231 cell line (231 R). The 231 R cell line developed in our lab showed an enhanced expression of the ATP-binding cassette (ABC) transporters P-gp1/MDR-1 and a declined miR-298 expression. The present delivery system is based on amine-functionalized mesoporous silica nanoparticles (MSNs), in which the side chain amine functional group was used to react with the carbonyl group of TQ, which acts as a pro-drug system (TQ-MSN) to release TQ and DOX simultaneously. DOX was encapsulated later into the above TQ-MSN by a simple diffusion method. The drugs containing MSNs were further coated with a hyaluronic acid-conjugated PEG–PLGA polymer (HA@TQ-DOX-MSN). This simple nanostrategy interferes with the MDR-1/miR-298 cross-talk, thereby allowing a significant reduction in drug efflux from the cell and highlighting a promising nanotechnology-based combinatorial delivery approach in managing breast cancer chemoresistance.

Low-Earth-orbit (LEO) satellite mega-constellations are beginning to include laser inter-satellite links (LISLs) to extend the Internet to the most remote locations on Earth. Since the process of establishing these links incurs a setup delay on the order of seconds, a static network topology is generally established well in advance, which is then used for the routing calculations. However, this involves keeping links active even when they are not being used to forward traffic, leading to a poor energy efficiency. Motivated by technological advances that are gradually decreasing the LISL setup delays, we foresee scenarios in which it will be possible to compute routes and establish dynamic LISLs on demand. This will require considering setup delays as penalties that will affect the end-to-end latency. In this article, we present a nonlinear optimization model that considers these penalties in the cost function and propose three heuristic algorithms that solve the problem in a tractable way. The algorithms establish different tradeoffs in terms of performance and computational complexity. We extensively analyze metrics including average latency, route change rate, outage probability, and jitter, in Starlink's Phase I version 2 constellation. The results show the benefit of adaptive routing schemes according to the link setup delay. In particular, more complex schemes are able to decrease the average end-to-end latency, in exchange for an increase in the execution time. On the other hand, depending on the maximum values of tolerated latency, it is possible to use less computationally complex schemes, which will be more scalable for the satellite mega-constellations of the future.

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Antimicrobial resistance (AMR) poses an important global health challenge in the 21st century. A previous study has quantified the global and regional burden of AMR for 2019, followed with additional publications that provided more detailed estimates for several WHO regions by country. To date, there have been no studies that produce comprehensive estimates of AMR burden across locations that encompass historical trends and future forecasts.

AbstractWe consider Gaussian approximation in a variant of the classical Johnson–Mehl birth–growth model with random growth speed. Seeds appear randomly in $\mathbb{R}^d$ at random times and start growing instantaneously in all directions with a random speed. The locations, birth times, and growth speeds of the seeds are given by a Poisson process. Under suitable conditions on the random growth speed, the time distribution, and a weight function $h\;:\;\mathbb{R}^d \times [0,\infty) \to [0,\infty)$ , we prove a Gaussian convergence of the sum of the weights at the exposed points, which are those seeds in the model that are not covered at the time of their birth. Such models have previously been considered, albeit with fixed growth speed. Moreover, using recent results on stabilization regions, we provide non-asymptotic bounds on the distance between the normalized sum of weights and a standard Gaussian random variable in the Wasserstein and Kolmogorov metrics.

A topological quantum phase transition has been identified for the first time for 24 π-conjugated polymers as a function of external longitudinal strain due to a level crossing of the frontier orbitals at the topological phase transition. Topological phase is determined by the presence/absence of edge states. Out of the 24 polymers 15 are traditionally assigned an aromatic character, and 9 are traditionally assigned a quinonoid character. We find that all aromatic ones correspond to the trivial topological phase (Zak invariant, Z2= 0), while all of the quinonoid ones to the nontrivial topological phase (Z2= 1) replacing the intuitive characterization of aromatic/quinonoid with the physically well-defined Zak invariant. Unique topological phase transition as a function of tensile strain can be achieved for four of the quinonoid ones. Tensile strain in these cases leads to a reduction of the bandgap. We introduced a figure of merit for indicating the efficiency of achievable very small bandgap upon the application of external strain.

AbstractPosttranslational protein arginylation has been shown as a key regulator of cellular processes in eukaryotes by affecting protein stability, function, and interaction with macromolecules. Thus, the enzyme Arginyltransferase and its targets, are of immense interest to modulate cellular processes in the normal and diseased state. While the study on the effect of this posttranslational modification in mammalian systems gained momentum in the recent times, the detail structures of human ATE1 (hATE1) enzymes has not been investigated so far. Thus, the purpose of this study was to predict the overall structure and the structure function relationship of hATE1 enzyme and its four isoforms. The structure of four ATE1 isoforms were modelled and were docked with 3’end of the Arg-tRNAArgwhich acts as arginine donor in the arginylation reaction, followed by MD simulation. All the isoforms showed two distinct domains. A compact domain and a somewhat flexible domain as observed in the RMSF plot. A distinct similarity in the overall structure and interacting residues were observed between hATE1-1 and X4 compared to hATE1-2 and 5. While the putative active sites of all the hATE1 isoforms were located at the same pocket, differences were observed in the active site residues across hATE1 isoforms suggesting different substrate specificity. Mining of nsSNPs showed several nsSNPs including cancer associated SNPs with deleterious consequences on hATE1 structure and function. Thus, the current study for the first time shows the structural differences in the mammalian ATE1 isoforms and their possible implications in the function of these proteins.Communicated by Ramaswamy H. Sarma

Global natural gas consumption has shown a general upward trend over the past few decades and continues to increase. Solidified natural gas (SNG) has carved a niche for stationary, large-scale, and long-term storage of natural gas. Herein, we employed 1,3-dioxane as a less toxic and less volatile thermodynamic additive to promote the formation of sII methane hydrate in seawater. The experiments were conducted to investigate the temperature effect on induction time, hydrate formation rate, and gas storage capacity across a broad range from 283.15 to 293.15 K. The growth behavior of hydrate crystals under different temperature conditions was also illustrated. Furthermore, we evaluated various pressure effects (7.5, 9.5, and 11.5 MPa) on hydrate formation in seawater while maintaining a constant temperature. Finally, the impact of three amino acids (l-tryptophan, l-leucine, and l-methionine) on hydrate formation was explored under 288.15 K and 11.5 MPa. The results revealed that a higher subcooling degree or higher driving force improves the kinetics of mixed CH4/dioxane hydrate formation in seawater. Among the amino acids tested, l-tryptophan demonstrated superior performance in enhancing gas storage capacity compared to l-leucine and l-methionine. The findings obtained in this work contribute to the development of environmentally benign SNG technology with efficient utlization of seawater.

This paper investigates a fixed point over a complete b-metric space for a family of contractive mappings. In this paper, we have discovered new results in the direction of the complete b-metric space by using Rus contraction. Furthermore, we establish a common fixed point theorem between two mappings over complete b-metric space. We also provide some non-trivial examples to display the authenticity of our established results.

This scoping review investigates the extent and nature of existing evidence on the role of non-governmental organizations (NGOs) and related mechanisms of engagement and challenges in issues of caring for older persons through digital technologies. We map research and practice gaps, contributing factors and best practices in NGOs. The rising use of digital technology in health care and the role that NGOs have in supporting older people in this context is relevant to nurses and service development leaders, particularly in the context of a rapidly changing care in the 21stcentury.

Online booking of homestays through e-travel portals is based on the virtual brand and perception, which are largely affected by user-generated electronic word-of-mouth (eWOM). With the objective of mining actionable insights from eWOM, this study conducted opinion mining for homestays located in four thematic areas of Kerala. Accordingly, various techniques have been deployed, such as sentiment and emotional analyses, topic modeling, and clustering methods. Key themes revealed from topic modeling were breakfast, facilities provided, ambience, bathroom, cleanliness, hospitality exhibited, and satisfaction with the host. A lasso logistic regression-based predictive binary text classification model (with 97.6% accuracy) for homestay recommendations was developed. Our findings and predictive model have implications for managers and homestay owners in devising appropriate marketing strategies and improving their overall guest experience.

Eutectic high-entropy alloys (EHEAs) have emerged as one of the most important classes of HEAs due to their nano-lamellar microstructure and attractive mechanical properties. Amongst the different EHEAs, the (L12+ B2) AlCoCrFeNi2.1has attracted overwhelming attention due to the ease of processing, tunable microstructure, and outstanding mechanical properties. Recent developments of cost-effective HEAs with tailored microstructure and properties offer significant cost-performance benefits for realizing the application potential of HEAs. Despite the outstanding mechanical properties of the EHEAs, several key challenges remain, including reliable prediction of EHEA compositions, designing cost-effective EHEAs without sacrificing mechanical properties, and expanding the potential application areas of EHEAs. The brief yet critical perspective presented here highlights the state-of-the-art, and underlines the future development and application areas.

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Gravastars are considered as exotic compact objects, may be found at the end of gravitational collapse of massive stars, to resolve the complexities of black holes. In this paper, we analyse the role of charge on the possible formation of an isotropic spherically symmetric gravastar configuration in the framework of Rastall gravity. Gravastar contains three distinct layers viz.(i) Interior region characterised by the equation of state, p=−ρ, which defines the repulsive outward pressure in the radial direction at all points on the thin shell, (ii) Thin shell contains an ultra-relativistic stiff fluid, which is denoted by the equation of state p=ρfollowing Zel'dovich's criteria for a cold baryonic universe, and can withstand the repulsive pressure exerted by the interior region, and (iii) Exterior region which is the vacuum space-time represented by the Reissner-Nordström solution. Following above specifications, we construct and analyse charged gravastar model in the framework of Rastall gravity, which represents several salient features. The basic physical attributes, viz.proper length, energy, entropy and equation of state parameter of the shell are investigated. In this model, it is interesting to note that for a large radius of the hypersurface (R), the equation of state parameter of the thin shell corresponds to a dark energy equation of state with W(R)→−1. However, for small value of R, W(R)→0, defines dust shell. The stability of the model is ensured through the study of gravitational surface redshift and maximisation of shell entropy within the framework of Rastall theory of gravity.

Abstract: Artificial hummingbird algorithm (AHA) is a recently developed swarm-based metaheuristic. The three food foraging strategies of natural hummingbirds, viz., guided, territorial and migration foraging using their three unique flight skills optimally via an intelligent memory updating mechanism, called visit table have been mathematically conversed in the AHA methodology, which enables the algorithm for an effective exploration-exploitation search characteristic. With an intention of further enhancement in the search quality of AHA, the nonlinear dynamics of the selected chaotic map, Gauss/mouse has been integrated with the algorithm framework, and proposed as chaotic artificial hummingbird algorithm (CAHA). During the earlier iterations of guided foraging, the chaos-embedded flight or direction vectors enhance the search-exploration of the process and thereby reduces the local optima convergence. In the later iterations of the same event, the exploitative search by the hummingbirds gets enhanced with these chaotic direction-control vectors. In the same way, the local search-exploitation during the territorial foraging is chaotically excited to obtain more accuracy in the optimized solutions. Further, the occurrence of these two foraging events has been chaotically sequenced for more effective diversifying search towards global optimization. Welded beam design, helical compression spring, pressure vessel, gear train, speed reducer, hollow shaft and multiple disc clutch brake are the considered mechanical component design cases for the present study to evaluate CAHA. Comparative analysis of the obtained results for all the problems with the leading designs of literature reveals that, CAHA performs significantly better in terms of solution robustness, convergence speed and the constraint fulfillment criteria. Graphical abstract:

The case of ‘Zomato’s Quest for Survival’ focuses on the concept of value relevance of accounting information. The case deals with financial ratio analysis, comparative financial statement analysis, cost–volume–profit analysis and DuPont analysis. The case also deals with the effect of acquisition on the acquiring firm’s fundamentals, post-acquisition. The case explores the potential growth of India’s food delivery market and goes on to explore Zomato’s business strategy and source of income. The case starts with Mr. Arghadip considering purchasing Zomato Ltd. Shares. He, therefore, gathered information from various sources to assess the company’s fundamentals and prospects for the future. A lot of questions worth discussing were brought up by the case. The ideal students for the case would be students of B.Com, M.Com, BBA and MBA. The case can also be discussed in Chartered Accountant and Cost and Management Accountant courses.

AbstractThe present treatment for Alzheimer’s disease (AD) involves well known synthetic acetylcholine esterase (AChE) inhibitor drugs which besides having short duration of action also have deleterious impact on human health. Therefore, there is a need for natural plant-based biomolecule(s) with potential AChE inhibition activity (ies). The aim of the work is to design a spice-based nano-vehicle as a novel green alternative of synthetic AD drugs by nanoencapsulating a solvent-less supercritical CO2extract of small cardamom seeds (SCE) having a synergistic consortium of five antioxidant molecules, using polyethylene glycol and emulsifiers, selected based on Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) analyses. Ellman’s assay and enzyme inhibition kinetics of the antioxidant molecules as well as the extract and its nanoliposomal formulation (SCE-NL) were performed, followed by rigorous molecular docking and dynamics studies using MM-PBSA and umbrella sampling. The antioxidants exhibited significant AChE inhibition in vitro, individually with 1, 8-cineole having the least IC50value of 65.53 ± 0.05 µg/mL. . Although SCE-NL had higher IC50value (575.67 ± 0.5 µg/mL) vis-à-vis that of rivastigmine (67.52 ± 0.02 µg/mL), it is safer for usage being ‘green’.The Lineweaver-Burk plots (Vmax∼1.04 mM/min) revealed competitive mode(s) of inhibition of AChE with each of these antioxidants. Binding energy analyses suggested very good binding free energies and stable docking/binding complexes (between the antioxidants and AChE). This study has delivered a nanoliposomal vehicle of food antioxidants as a putative ‘green’ alternative of synthetic AChE inhibitor drugs.Communicated by Ramaswamy H. Sarma