Potential Effect Research Articles

Amalgamated Pharmacoinformatics Study to Investigate the Mechanism of Xiao Jianzhong Tang against Chronic Atrophic Gastritis.

Traditional Chinese medicine (TCM) Xiao Jianzhong Tang (XJZ) has a favorable efficacy in the treatment of chronic atrophic gastritis (CAG). However, its pharmacological mechanism has not been fully explained. The purpose of this study was to find the potential mechanism of XJZ in the treatment of CAG using pharmacocoinformatics approaches. Network pharmacology was used to screen out the key compounds and key targets, MODELLER and GNNRefine were used to repair and refine proteins, Autodock vina was employed to perform molecular docking, Δ Lin_F9XGB was used to score the docking results, and Gromacs was used to perform molecular dynamics simulations (MD). Kaempferol, licochalcone A, and naringenin, were obtained as key compounds, while AKT1, MAPK1, MAPK14, RELA, STAT1, and STAT3 were acquired as key targets. Among docking results, 12 complexes scored greater than five. They were run for 50ns MD. The free binding energy of AKT1-licochalcone A and MAPK1-licochalcone A was less than -15 kcal/mol and AKT1-naringenin and STAT3-licochalcone A was less than -9 kcal/mol. These complexes were crucial in XJZ treating CAG. Our findings suggest that licochalcone A could act on AKT1, MAPK1, and STAT3, and naringenin could act on AKT1 to play the potential therapeutic effect on CAG. The work also provides a powerful approach to interpreting the complex mechanism of TCM through the amalgamation of network pharmacology, deep learning-based protein refinement, molecular docking, machine learning-based binding affinity estimation, MD simulations, and MM-PBSA-based estimation of binding free energy.

Observational Test of f(Q) Gravity with Weak Gravitational Lensing

In this article we confront a class of f(Q) gravity models with observational data of galaxy–galaxy lensing. Specifically, we consider f(Q) gravity models containing a small quadratic correction when compared with general relativity (GR), and quantify this correction by a model parameter, α. To derive the observational constraints, we start by extracting spherically symmetric solutions, which correspond to deviations from the Schwarzschild solution that depends on the model parameters in a twofold way, i.e., a renormalized mass and a new term proportional to r −2. Then, we calculate the effective lensing potential, the deflection angle, the shear component, and the effective excess surface density profile. After that, we employ a group catalog and a shape catalog from the Sloan Digital Sky Survey Data Release 7 for the lens and source samples, respectively. Moreover, we handle the off-center radius as a free parameter and constrain it using a Markov Chain Monte Carlo method. Concerning the deviation parameter from GR we derive α=1.202−0.179+0.277×10−6Mpc−2 at the 1σ confidence level, and then compare the fitting efficiency with the standard Λ cold dark matter paradigm by applying the Akaike information criterion and Bayesian information criterion. Our results indicate that the f(Q) corrections alongside the off-center effect yield a scenario that is slightly favored.

Accurate nuclear quantum statistics on machine-learned classical effective potentials.

The contribution of nuclear quantum effects (NQEs) to the properties of various hydrogen-bound systems, including biomolecules, is increasingly recognized. Despite the development of many acceleration techniques, the computational overhead of incorporating NQEs in complex systems is sizable, particularly at low temperatures. In this work, we leverage deep learning and multiscale coarse-graining techniques to mitigate the computational burden of path integral molecular dynamics (PIMD). In particular, we employ a machine-learned potential to accurately represent corrections to classical potentials, thereby significantly reducing the computational cost of simulating NQEs. We validate our approach using four distinct systems: Morse potential, Zundel cation, single water molecule, and bulk water. Our framework allows us to accurately compute position-dependent static properties, as demonstrated by the excellent agreement obtained between the machine-learned potential and computationally intensive PIMD calculations, even in the presence of strong NQEs. This approach opens the way to the development of transferable machine-learned potentials capable of accurately reproducing NQEs in a wide range of molecular systems.

Chitosan-graft-poly(lactide) nanocarriers: An efficient antioxidant delivery system for combating oxidative stress

Oxidative stress is a key factor in various diseases, and thus exogenous antioxidants offer effective therapeutic potential. While astaxanthin (ATX) is a potent natural antioxidant, its poor water solubility, bioavailability, and stability hinder its application. This study aimed to develop an amphiphilic chitosan-graft-poly(lactide) (CS-g-PLA) copolymer utilizing a new strategy by ring-opening polymerization of D, l-lactide via organosoluble CS/sodium dodecyl sulfate complex. Subsequently, CS-g-PLA micelles were prepared for efficient encapsulation and delivery of ATX. CS-g-PLA copolymers were characterized by FT-IR and 1H NMR. Transmission electron microscopy and dynamic light scattering revealed micellar morphology and size distribution. The antioxidant activity of CS-g-PLA/ATX was assessed using the DPPH assay, demonstrating significant improvement compared to free ATX. Furthermore, the cytotoxicity of micellar ATX was evaluated on H2O2-treated bone marrow mesenchymal stem cells (BMSCs) using MTT assay. Annexin V staining and mitochondrial membrane potential (∆Ψm) analysis revealed reduced apoptosis and enhanced protection by ATX-loaded micelles compared to free ATX. These findings suggest CS-g-PLA micelles as promising nanocarriers for ATX delivery, putatively enhancing its antioxidant potential and protecting stem cells in oxidative stress environments. This approach could hold significant implications for stem cell therapy in diseases associated with oxidative stress.

Probing the effect of time conformal factor on the particle dynamics around AdS Reissner–Nordström black hole

This study entails the effect of time on particle dynamics (both charged and uncharged) in the surrounding of the Reissner–Nordström AdS black hole in light of a general time conformal factor by acquiring Noether symmetry relation using the Lagrangian of the considered black hole spacetime. Upon acquiring the required time conformal spacetime as well as the Noether and approximated Noether symmetries along with their respective laws of conservation, the study further aims at investigating different parameters, like effective potential, effective force, and trajectories of escape velocity for the particle dynamics of the specified black hole. Additionally, in order to investigate orbit stability, the study employs the Lyapunov exponent.

Dual effect of string cloud and dark matter halos on particle motions, shadows and epicyclic oscillations around Schwarzschild black holes

In this work, we study the particle dynamics, shadows and quasi-periodic oscillations around the Schwarzschild black hole with three different dark matter halos and string cloud parameters. The motion of particles is considered with the string cloud parameter α and investigated for massive and massless particles. The photon orbits and inner stable circular orbits of these black holes are obtained from the effective potential. The black hole shadows are calculated using three different dark matter halos. The shadow radius of these black holes increases compared to a pure Schwarzschild black hole for different values of the string cloud parameter. Further, quasi-periodic oscillations are also discussed in the current analysis. Our study examines how the radial profiles of orbital and radial harmonic oscillation frequencies change with the string cloud parameter. This study examines the major properties of test particle's quasi-periodic oscillations near stable circular orbits in the black hole equatorial plane. Our findings indicate that observational tests for black holes influenced by dark matter halos and cloud strings are also feasible and viable.

Second resonance of the Higgs field: motivations, experimental signals, unitarity constraints

Perturbative calculations predict that the effective potential of the Standard Model should have a new minimum, well beyond the Planck scale, which is much deeper than the electroweak vacuum. So far, most authors have accepted the metastability scenario in a cosmological perspective which is needed to explain why the theory remains trapped in our electroweak vacuum but requires to control the properties of matter in the extreme conditions of the early universe. As an alternative, one can consider the completely different idea of a non-perturbative effective potential that, as at the beginning of the Standard Model, is restricted to the pure Φ4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\Phi ^4$$\\end{document} sector but is consistent with the indications of the now existing analytical and numerical studies, namely “triviality” and a description of SSB as weak first-order phase transition. In this approach, the electroweak vacuum is now the lowest energy state because, besides the state with mass mh=125\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$m_h=125$$\\end{document} GeV, defined by the quadratic shape of the potential at its minimum, there is a second much larger mass scale (MH)Theor∼690(30)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(M_H)^\ extrm{Theor} \\sim 690(30)$$\\end{document} GeV associated with the zero-point energy determining the potential depth. Despite its large mass, the heavier state would couple to longitudinal Ws with the same typical strength as the low-mass state at 125 GeV and thus represent a relatively narrow resonance mainly produced at LHC by gluon-gluon fusion. Therefore, it is interesting that, in the LHC data, one can find combined indications of a new resonance of mass (MH)comb∼685(10)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(M_H)^\ extrm{comb} \\sim 685 (10)$$\\end{document} GeV, with a statistical significance which is far from negligible. Since this non-negligible evidence could become an important new discovery with forthcoming data, we outline further refinements of the theoretical predictions, that could be obtained by implementing unitarity constraints, in the presence of fermion and gauge fields, with the type of coupled-channel calculations nowadays used in meson spectroscopy.

Circular motion and QPOs near black holes in Kalb–Ramond gravity

General relativity (GR) theory modifications include different scalar, vector, and tensor fields with non-minimal gravitational coupling. Kalb–Ramond (KR) gravity is a modified theory formulated based on the presence of the bosonic field. One astrophysical way to test gravity is by studying the motion of test particles in the spacetime of black holes (BHs) using observational data. In the present work, we aimed to test KR gravity through theoretical studies of epicyclic frequencies of particle oscillations using quasi-periodic oscillation (QPO) frequency data from microquasars. First, we derive equations of motion and analyze the effective potential for circular orbits. Also, we studied the energy and angular momentum of particles corresponding to circular orbits. In addition, we analyze the stability of circular orbits. It is shown that the radius of the innermost stable circular orbits is inversely proportional to the KR parameter. We are also interested in how the energy and angular momentum of test particles at ISCO behave around the KR BHs. We found that the Keplerian frequency for the test particles in KR gravity is the same as that in GR. Finally, we study the QPOs by applying epicyclic oscillations in the relativistic precession (RP), warped disc (WD), and epicyclic resonance (ER) models. We also analyze QPO orbits in the resonance cases of upper and lower frequencies 3:2, 4:3, and 5:4 in the QPO as mentioned above models. We obtain constraints on the KR gravity parameter and BH mass using a Monte Carlo Markov Chain simulation in the multidimensional parameter space for the microquasars GRO J1655-40 & XTE J1550-564, M82 X-1, and Sgr A*.

Bifurcation and spectral instability of asymptotic quasinormal modes in the modified Pöschl-Teller effective potential

Bifurcation and spectral instability of asymptotic quasinormal modes in the modified Pöschl-Teller effective potential

Relativistic two-fluid hydrodynamics with quantized vorticity from the nonlinear Klein-Gordon equation

Abstract We consider a relativistic two-fluid model of superfluidity, in which the superfluid is described by an order parameter that is a complex scalar field satisfying the nonlinear Klein-Gordon equation (NLKG). The coupling to the normal fluid is introduced via a covariant current-current interaction, which results in the addition of an effective potential, whose imaginary part describes particle transfer between superfluid and normal fluid. Quantized vorticity arises in a class of singular solutions and the related vortex dynamics is incorporated in the modified NLKG, facilitating numerical analysis which is usually very complicated in the phenomenology of vortex filaments. The dual transformation to a string theory description (Kalb-Ramond) of quantum vorticity, the Magnus force and the mutual friction between quantized vortices and normal fluid are also studied.

Predicting possible molecular states of nucleons with Ξc,Ξc* , and Ξc′

In the framework of a one-boson-exchange model, we carry out a comprehensive investigation of the ΞcN/ΛcΣ/Ξc′N/ΣcΛ/Ξc*N/Σc*Λ/ΣcΣ/Σc*Σ interactions. We consider the S−D-wave mixing effects and the coupled-channel effects to derive the relevant effective potentials. Our results can predict several possible charm-strange deuteronlike Ξc(′,*)N hexaquarks, the Ξc′N molecules with I(IP)=0(0+), 0(1+), 1(1+), the Ξc*N molecules with 0(1+), 0(2+), 1(2+), and the coupled ΞcN/Ξc′N/Ξc*N/ΣcΣ/Σc*Σ molecule with 0(1+). We expect the experiments to search for our predictions of the Ξc(′,*)N bound states. Published by the American Physical Society 2024

Circular motion of a charged particle on the inner surface of a frictionless cone under the influence of an electric field due to an electric dipole

A common problem provided in elementary physics textbooks is the analysis of the circular motion of a point-like particle affected by a gravitational field on the frictionless inner surface of an inverted cone. In this research, we study the motion of a charged particle on the same surface subject to an electric field generated by an electric dipole placed at the bottom of the cone. We study negatively and positively charged particles and analyse the dynamics of both. We calculate the physical quantities such as speed, angular velocity, angular momentum, and mechanical energy. Furthermore, we determine all possible distances travelled by the particles measured from the dipole. We also discuss the stability of the circular orbit using the effective potential. Finally, we consider the particle’s motion on a generic surface formed by the revolution of the curve ρz around the vertical axis. We determine the differential equation of ρz , in which the kinematic variables including speed v, angular velocity ω, and angular momentum L are constant.

How Cells Stay Together: A Mechanism for Maintenance of a Robust Cluster Explored by Local and Non-local Continuum Models.

Formation of organs and specialized tissues in embryonic development requires migration of cells to specific targets. In some instances, such cells migrate as a robust cluster. We here explore a recent local approximation of non-local continuum models by Falcó et al. (SIAM J Appl Math 84:17-42, 2023). We apply their theoretical results by specifying biologically-based cell-cell interactions, showing how such cell communication results in an effective attraction-repulsion Morse potential. We then explore the clustering instability, the existence and size of the cluster, and its stability. For attractant-repellent chemotaxis, we derive an explicit condition on cell and chemical properties that guarantee the existence of robust clusters. We also extend their work by investigating the accuracy of the local approximation relative to the full non-local model.

Improved Topical Delivery of Sorafenib-Meglumine Antimoniate: Elastic Nano-Liposomal Formulation for the Treatment of Cutaneous Leishmaniasis

Background: Cutaneous leishmaniasis (CL) is a widespread parasitic disease with significant health and social impacts. Current systemic treatments have severe side effects, highlighting the need for effective topical alternatives.Objective: This study aimed to develop and evaluate the effectiveness of sorafenib (SF) and meglumine antimoniate (MM) dual-loaded transferosomes (TRs) for topical treatment of CL.Methods: TRs were prepared using a thin film hydration method and incorporated into a carbopol gel. The formulations were characterized for vesicle size, zeta potential, entrapment efficiency, and deformability index. In vivo and ex vivo skin permeation studies were conducted, along with anti-leishmanial efficacy testing on an intramacrophage amastigote model using BALB/c mice.Results: The TRs exhibited a vesicle size of 186.1 ± 65.89 nm, zeta potential of -27.9 mV, and entrapment efficiency of 71.7 ± 3.9% for MM and 78.6 ± 4.2% for SF. Ex vivo studies showed enhanced skin permeation with cumulative permeation of 327.6 ± 29.4 µg/cm² for MM and 291.6 ± 28.3 µg/cm² for SF. In vivo results indicated a significant reduction in lesion size (0.1 ± 0.12 mm) and parasite load (2.7 ± 0.3 log scale).Conclusion: The MM-SF dual-loaded TRs demonstrated effective topical delivery and therapeutic potential for CL, providing a promising alternative to systemic treatments.

Improved thermal resummation for multi-field potentials

The resummation of large thermal corrections to the effective potential is mandatory for the accurate prediction of phase transitions. We discuss the accuracy of different prescriptions to perform this resummation at the one- and two-loop level and point out conceptual issues that appear when using a high-temperature expansion at the two-loop level. Moreover, we show how a particular prescription called partial dressing, which does not rely on a high-temperature expansion, consistently avoids these issues. We introduce a novel technique to apply this resummation method to the case of multiple mixing fields. Our approach significantly extends the range of applicability of the partial dressing prescription, making it suitable for phenomenological studies of beyond the Standard Model extensions of the Higgs sector.

Greybody factor of uncharged black hole in symmetric teleparallel gravity

In this study, we investigate the greybody factor of a (3+1)-dimensional black hole solution in the context of alternative f(Q) gravity with minimum scalar field coupling. We obtain the radial equation by applying the Klein–Gordon equation and transforming it into a Schrodinger wave equation using the tortoise coordinate. This transformation enables us to determine the effective potential and its graphical behavior for different values of the coupling constant and relevant physical parameters. We obtain two solutions for the radial equation corresponding to the event and cosmological horizons. To determine the greybody factor and its behavior, we combine these two solutions in the intermediate regime. The greybody factor increases with an increase in radius and coupling constant. This indicates that in alternative gravity, the larger black hole will die sooner as compared to cosmic gravity.

Remittance Inflow, Investment, and Economic Growth in Africa amidst COVID-19 Pandemic

Africa has fared well in the aspect of remittance receipts in recent years; however, the region recorded a decline in remittances amid the COVID-19 pandemic which constrained the circular flow of income significantly and ultimately economic growth. In view of this, this study investigates the economic effects of remittance inflows and investment on economic growth in Africa amid COVID-19 pandemic using a panel of 48 economies and estimated with pooled OLS and two-step system GMM. The study employed two distinct approaches for estimation; pre-COVID-19 (2010–2019) and amid COVID-19 (2010–2023). The results indicate that the behavior of remittances, investment and economic growth in Africa is not significantly different between pre-COVID-19 and amid COVID-19. That is, remittances remain a significant economic growth catalyst in Africa whereas investment is not (though with growth effect potential). Overall, the study concludes that African economic policy stakeholders and other relevant policy authorities should sustain the current remittance and labor policy frameworks with possible fine-tuning where applicable while doubling their investment efforts especially in productive sectors of the economy.

The cosmological constant problem and the effective potential of a gravity-coupled scalar

We consider a quantum scalar field in a classical (Euclidean) De Sitter background, whose radius is fixed dynamically by Einstein’s equations. In the case of a free scalar, it has been shown by Becker and Reuter that if one regulates the quantum effective action by putting a cutoff N on the modes of the quantum field, the radius is driven dynamically to infinity when N tends to infinity. We show that this result holds also in the case of a self-interacting scalar, both in the symmetric and broken-symmetry phase. Furthermore, when the gravitational background is put on shell, the quantum corrections to the mass and quartic self-coupling are found to be finite.

Comparison of optimized effective potential with inverse Kohn-Sham method for Hartree-Fock exchange energy.

The inverse Kohn-Sham (inv-KS) density-functional theory for the electron density of the Hartree-Fock (HF) wave function was revisited within the context of the optimized effective potential (HF-OEP). First, we clarify the relationship between the inv-KS and the HF-OEP within the framework of the potential-functional theory. The similarities and the differences of the approaches are then discussed on the basis of their methodological details, which motivates comparisons of the wave function provided by each method. Next, the real-space grid implementations of the inv-KS and the HF-OEP are addressed for the comparisons. The total HF energies EHF[{φiinv-KS}] for the wave functions φiinv-KS on the effective potentials optimized by the inv-KS are computed for a set of small molecules. It is found that the mean absolute deviation (MAD) of EHF[{φiinv-KS}] from the HF energy is clearly smaller than the MAD of EHF[{φiOEP}], demonstrating that the inv-KS is advantageous in constructing the detailed structure of the exchange potential υx as compared with the HF-OEP. The inv-KS method is also applied to an ortho-benzyne radical known as a strongly correlated polyatomic molecule. It is revealed that the spin populations on the atomic sites computed by the UHF calculation can be faithfully reproduced by the wave functions on the inv-KS potential.

A novel radial air-breathing proton exchange membrane fuel cell for miniaturized applications with effective stacking potentials

Increasing volumetric power density in fuel cells can be accomplished by increasing its compactness or output power. This is very crucial for miniaturized applications due to constraints in available spaces. In this study, a three-dimensional, multiphase, and non-isothermal computational fluid dynamics (CFD) tool is used to develop a novel radial air-breathing (AB) PEM fuel cell for miniaturized applications, which has unique stack-ability feature. The noted cell can accommodate multiply higher active area in cathode electrode with respect to planar and tubular AB designs. Increasing the cathode side active area, the electrode with the highest sources of losses for the kinetics of reactions in proton exchange membrane (PEM) fuel cells, has shown to play a significant role in performance enhancement of radial AB cells. For instance, at 0.4 Acm−2 the radial AB PEM fuel cell, can deliver 27.9 % and 10 % more power than the earlier planar and tubular AB ones, respectively. The stack-ability of AB fuel cells usually face severe challenges due to non-uniform air supply to the cells, resulting in imbalance of the cells output power. As opposed to tubular and planar AB cells, one unique feature for the present radial AB stack design is its attack-ability that ensures adequate and uniform supply of air/oxygen to all cells.