Polarization Functions Research Articles

Generalizing the Cross Product to N Dimensions: A Novel Approach for Multidimensional Analysis and Applications

This paper presents a generalization of the cross product to N dimensions, extending the classical operation beyond its traditional confines in three-dimensional space. By redefining the cross product to accommodate N−1 arguments in N dimensions, a framework has been established that retains the core properties of orthogonality, magnitude, and anticommutativity. The proposed method leverages the determinant approach and introduces the polar sine function to calculate the magnitude of the cross product, linking it directly to the volume of an N-dimensional parallelotope. This generalization not only enriches the theoretical foundation of vector calculus but also opens up new applications in high-dimensional data analysis, machine learning, and multivariate time series. The results suggest that this extension of the cross product could serve as a powerful tool for modeling complex interactions in multi-dimensional spaces, with potential implications across various scientific and engineering disciplines.

Interferon regulatory factor 2 of red-spotted grouper (Epinephelus akaara): Insights into its transcriptional profiling, antiviral potential, and function in macrophage polarization.

Interferon regulatory factor 2 (IRF2) is a member of the IRF family that is specifically involved in diverse immune responses via interferon (IFN)/IRF-dependent signaling pathways. In this study, IRF2 of Epinephelus akaara (EAIRF2) was identified and characterized by evaluating its structural and functional properties. EAIRF2 showed the highest homology with IRF2 of Epinephelus coioides and clustered with teleosts in the phylogenetic tree. The highest level of EAIRF2 mRNA was found in the blood under normal physiological conditions. In the immune challenge experiment, significant transcriptional modulation of EAIRF2 upon lipopolysaccharide (LPS), polyinosinic: polycytidylic acid (poly I:C), and nervous necrosis virus (NNV) challenge were observed. The subcellular localization assay confirmed the role of EAIRF2 as a transcription factor by revealing its specific nuclear localization. To elucidate its functional implications in antiviral defense, EAIRF2 was overexpressed in fathead minnow cells, which were subsequently infected with viral hemorrhagic septicemia virus (VHSV). Notably, cells overexpressing EAIRF2 exhibited a significant reduction in the transcription of VHSV genes. Concurrently, the genes associated with the IFN/IRF signaling pathway were upregulated. Furthermore, the Hoechst and propidium iodide dual staining assay, water-soluble tetrazolium-1 (WST-1) assay, and transcriptional analysis of B-cell lymphoma 2-associated X protein (Bax)/B-cell lymphoma 2 (Bcl-2) indicated that EAIRF2 possesses anti-apoptotic properties during viral infection and poly I:C treatment. Additionally, EAIRF2 overexpression in murine macrophages induced M1 polarization and augmented relative marker gene expression. Collectively, these findings suggest that EAIRF2 is a pivotal immune-related gene, specifically implicated in the IFN/IRF-mediated antiviral defense mechanism, apoptotic signaling pathway, and activation of macrophage-mediated immune responses in Epinephelus akaara. The finding of this study enhances our understanding of IRF2's function in teleost immunity and presents potential avenues for developing therapeutic strategies against viral infections and other immune-related conditions in aquaculture species.

Effects of Porphyromonas gingivalis Outer Membrane Vesicles (OMVs) on Macrophages in Periodontitis.

To review the effect of outer membrane vesicles (OMVs) of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis) on macrophages during periodontitis development. Literature pertaining to P. gingivalis OMVs and macrophages was reviewed and discussed, with a focus on the immunomodulatory effects of P. gingivalis OMVs on macrophages. P. gingivalis OMVs affect the recognition, phagocytosis, polarization, and apoptosis functions of macrophages. However, information on their antigen-presenting effect remains lacking, and further research is required for clinical applications. P. gingivalis OMVs can influence the development of periodontitis through immune modulation of macrophages; however, further research is required to provide novel ideas for the prevention and treatment of periodontitis.

P0183 GSDMD regulates interactions between macrophages and intestinal epithelial cells in inflammatory bowel disease

Abstract Background Our previous studies have demonstrated the significant role of the GSDMD-mediated pyroptotic pathway in inflammatory bowel disease (IBD). However, there remains some controversy surrounding the research findings concerning GSDMD in IBD. Methods Employing lentiviral transduction techniques, we manipulated GSDMD expression levels in THP-1 and HT-29 cells, assessing the impact of GSDMD on macrophage M1 polarization and epithelial barrier function. Further, co-culturing transduced THP-1 and HT-29 cells enabled the examination of changes in the intestinal barrier. Moreover, we generated conditional knockout mice with Gsdmdflox/floxLyz2-Cre and Gsdmdflox/floxVillin1-Cre, inducing experimental colitis with dextran sodium sulfate (DSS) to evaluate mucosal macrophage phenotypes and intestinal barrier integrity. Additionally, primary macrophages and intestinal epithelial cells were co-cultured, and downstream inflammatory factors were screened through transcriptome sequencing. Results Knockdown of GSDMD in THP-1 cells significantly reduces CD86 expression, indicating a decrease in M1 polarization efficiency, whereas overexpression of GSDMD yields opposite results. In HT-29 cells, overexpression of GSDMD followed by LPS treatment leads to a significant decrease expression of Claudin-1, Occludin, and Zo-1, whereas knockdown of GSDMD shows the opposite outcome. ELISA results demonstrate a correlation between GSDMD expression levels and levels of LDH, IL-1β, IL-18, TNF-α, and IL-6. In the inflammatory co-culture model of THP-1 and HT-29 cells with double knockdown of GSDMD, the severity of intestinal barrier damage and release of inflammatory factors is minimal. Conversely, in the inflammatory co-culture model of THP-1 and HT-29 cells with double overexpression of GSDMD, the intestinal barrier damage and release of inflammatory factors are maximal. Following DSS-induced colitis, compared to the Gsdmdflox/flox group, two conditional knockout mice exhibit reduced inflammatory evaluation. Furthermore, the protein expression of Zo-1, Occludin, and Claudin-1 in two conditional knockout mice is significantly higher than that in the Gsdmdflox/flox group. Flow cytometry results show that the proportion of M1 macrophages in the mucosal lamina propria is significantly lower in two conditional knockout mice compared to the Gsdmdflox/flox group. Additionally, primary macrophage and intestinal epithelial cell co-culture experiments, coupled with transcriptomic sequencing, revealed IL-1β as a downstream mediator of GSDMD-mediated macrophage-epithelial cell interplay. Conclusion It was confirmed that GSDMD serves as a key target in the pathological interplay between macrophages and epithelial cells.

Dynamical polarization function, anisotropic plasmon modes, and dephasing rates for interacting electrons in semi-Dirac bands

Dynamical polarization function, anisotropic plasmon modes, and dephasing rates for interacting electrons in semi-Dirac bands

Strain Control of Third Harmonic Generation in Nb2SiTe4 Driven by Tuneable Anisotropic Characteristics

AbstractStrain engineering constitutes one of the main control knobs for material properties. The material's crystal and band structure can be strongly modified by mechanical strain, thus tailoring the electronic and photonic properties toward specific applications. However, the strain control of the higher‐order nonlinear optical (NLO) processes in crystals characterized by in‐plane anisotropy remains mostly unexplored. It is demonstrated that 2D ternary Nb2SiTe4 crystals provide an excellent platform for tuning NLO properties with uniaxial strain due to the inherently anisotropic band structure around the fundamental bandgap in the near‐infrared region. Resonant conditions between the interband excitations and third harmonic signals are realized, a record‐high third‐order susceptibility of 2.43 × 10−18m2/V2 is observed, exceeding by over an order of magnitude the values reported for commonly used NLO crystals. The measurements of the third harmonic intensity as a function of the linear polarization revealed that the anisotropic characteristics of Nb2SiTe4 can be tuned into qualitatively different regimes by the application of a uniaxial strain along the principal crystallographic axes. Notably, with increasing strain, the characteristic anisotropic direction can be reoriented. The findings provide unique perspectives for applying the modulation of the broadband NLO properties enabled by anisotropic materials in optoelectronics and all‐optical devices.

Effect of chiral imbalance on the electrical conductivity of hot and dense quark matter using Green–Kubo method within the 2-flavour gauged NJL model

The electrical conductivity of hot and dense quark matter is calculated using the 2-flavour gauged Nambu–Jona–Lasinio (NJL) model in the presence of a chiral imbalance quantified in terms of a chiral chemical potential (CCP). To this end, the in-medium spectral function corresponding to the vector current correlator is evaluated employing the real time formulation of finite temperature field theory. Taking the long wavelength limit of the spectral function we extract the electrical conductivity using the Green–Kubo relation. The thermal widths of the quarks/antiquarks that appear in the expression of electrical conductivity are calculated by considering the 2→2 scattering in the NJL model. The scattering amplitudes containing the polarization functions of the mesonic modes in the scalar and pseudoscalar channels are also evaluated by considering finite value of CCP. We find that the ratio of electrical conductivity to temperature has significant dependence on CCP especially in the low temperature region.

Structural mechanism of CB1R binding to peripheral and biased inverse agonists

The cannabinoid receptor 1 (CB1R) regulates synaptic transmission in the central nervous system, but also has important roles in the peripheral organs controlling cellular metabolism. While earlier generations of brain penetrant CB1R antagonists advanced to the clinic for their effective treatment of obesity, such molecules were ultimately shown to exhibit negative effects on central reward pathways that thwarted their further therapeutic development. The peripherally restricted CB1R inverse agonists MRI-1867 and MRI-1891 represent a new generation of compounds that retain the metabolic benefits of CB1R inhibitors while sparing the negative psychiatric effects. To understand the mechanism of binding and inhibition of CB1R by peripherally restricted antagonists, we developed a nanobody/fusion protein strategy for high-resolution cryo-EM structure determination of the GPCR inactive state, and used this method to determine structures of CB1R bound to either MRI-1867 or MRI-1891. These structures reveal how these compounds retain high affinity and specificity for CB1R’s hydrophobic orthosteric site despite incorporating polar functionalities that lead to peripheral restriction. Further, the structure of the MRI-1891 complex along with accompanying molecular dynamics simulations shows how differential engagement with transmembrane helices and the proximal N-terminus can propagate through the receptor to contribute to biased inhibition of β-arrestin signaling.

Molecular Design and Alignment for Ambipolar SCLC Mobility in Self-Assembled Columnar Discogens.

The future of next-generation electronics relies on low-cost organic semiconductors that are tailored to simultaneously provide all requisite optoelectronic properties, focusing greatly on ambipolar charge-transport and solution processability. In this regard, room-temperature discotic liquid crystals (DLCs) are potential candidates, where quasi-1D self-assembly affords a charge-transport channel along their columnar axis. This work shows a molecular design strategy by utilizing anthraquinone as the primary motif, surrounded by ester functionalized tri-alkoxy phenyl units to develop room-temperature DLCs (1.1-1.3). Here, the polar ester functionality stabilizes the columnar mesophase over a wide range through the involvement of dipole-dipole interaction along with the π-π stacking. Throughout the entire mesophase transition, reported compounds 1.1-1.3 exhibit a highly ordered 2D columnar oblique (Colob) self-assembly. Space charge limited current (SCLC) experiments reveal balanced ambipolar charge transport, with the maximum hole and electron mobilities of 5.04 and 4.93 cm2 V-1 s-1, respectively. From the conoscopic results, their propensity to align in a highly homeotropic fashion is demonstrated. It is further justified by the azimuthal plot corresponding to the (11) peak of grazing incidence small angle X-ray scattering (GISAXS), denoting the crucial role of the design and alignment for efficient movement of charge carriers in the material.

Phonon-Induced Wake Potential in a Graphene-Insulator -Graphene Structure.

The aim of this study is to explore the potential which arises in a graphene-insulator-graphene structure when an external charged particle is moving parallel to it with a speed smaller than the Fermi speed in graphene. This is achieved by employing the dynamic polarization function of graphene within the random phase approximation, where its π electrons are modeled as Dirac fermions, and utilizing a local dielectric function for bulk insulators. Three different insulators are considered: SiO2, HfO2, and Al2O3. It is observed that the wake potential is induced by the surface optical phonons originating from the insulator layer, and that total potential could be effectively decomposed into two components, each corresponding to different phonon branches, as long as those branches do not interact amongst themselves.

Theoretical studies on the scattering of e± off the C2H2 molecule

Abstract By employing previous models [15,18], we report the differential, integrated elastic, inelastic, total (elastic+inelastic), viscosity and momentum transfer cross sections of e±- C2H2 collision dynamics, for the energy range of 1 eV-1 MeV. This report also incorporates Sherman spin polarization function and total ionization cross section. This work provides the first comprehensive study of electron/positron scattering from C2H2 over such a wide energy range. A complex optical model potential (OMP) has been used to represent the projectile-atom interaction. Relativistic Dirac equation has been solved, to get phase-shifts, needed for the calculations of scattering observables, using OMP. Our results are compared with the existing experimental data and theoretical calculations.

Formation of dimer and higher aggregates of methylene blue in alcohol

This study investigates MB aggregation in propanol, ethanol, butanol, and methanol using UV–Visible, steady-state, and time-resolved fluorescence spectroscopy at room temperature. This work reveals the presence of monomers, dimers, and higher aggregates across various concentrations, affecting both the absorption spectra and fluorescence intensity. Characteristic peaks for monomeric, dimeric, and higher aggregates of MB are identified, with shifts in emission peak intensity and lifetime as a function of concentration, solvent polarity, and viscosity. A strong correlation between fluorescence lifetime and solvent properties, such as dielectric constant and viscosity, suggests that solvent polarity and viscosity significantly influence the stabilization of excited states and the deactivation dynamics of methylene blue. The critical concentration for MB aggregation is identified for each solvent and is found to be higher in solvents with a greater dielectric constant, likely due to Van der Waals forces dominating over Coulombic interactions in the aggregation process. The findings indicate that MB aggregation in alcohols differs from that in aqueous solutions, underscoring the importance of the solvent environment in MB’s aggregation and fluorescence behavior, with implications for optimizing its use in laser and photomedicine applications.

Effects of urea-functionalized MoS2 on hydrophilic lubrication

The challenge of achieving effective lubrication in polar lubricants like Water, Ethylene Glycol (EG), and Glycerol has driven the search for advanced lubricant additives. Traditional MoS2, while widely used in nonpolar lubricants, suffers from poor dispersion stability and inconsistent performance in polar solvents due to its hydrophobic nature. This study addresses those issues by functionalizing MoS2 with urea (U-MoS2) to improve its compatibility with polar lubricants. U-MoS2 was synthesized through a two-step process involving oxidation followed by urea functionalization. The results show that U-MoS2 significantly enhances dispersion stability, maintaining a uniform suspension for over 30 days. Rheological analysis revealed that U-MoS2 reduced the viscosity of Water, while in EG and Glycerol, it caused a slight increase in viscosity across the temperature range of 25 to 80 °C. Tribological experiments revealed a substantial reduction in the coefficient of friction (COF) for U-MoS2-enhanced lubricants. In Water-based systems, the COF was reduced by 84 %, dropping to 0.057 with U-MoS2. In EG and Glycerol-based systems, the COF reductions were 41 % and 38 %, respectively. Additionally, wear rate analysis demonstrated an 81 % reduction in wear for Water after introducing U-MoS2, a 51 % reduction for EG, and a 69 % reduction for Glycerol. Wear surface analysis first revealed the presence of a consistent MoS2 film on the contact surfaces, contributing to the observed reduction in wear and friction. These outcomes suggest that the urea molecule plays a key role in enhancing the adhesion of MoS2 to the substrate and facilitates the formation of a stable lubricating layer. By addressing the limitations of traditional MoS2 in polar solvents, this research aims to understand how polar functionalization can improve the performance of MoS2 in hydrophilic lubrication, potentially expanding its applications across various industrial sectors.

Emerging role of macrophage polarization in disease

Abstract. Macrophages, present in many human cells and play an essential duty in human body, Triggered macrophages are usually separated into 2 phenotypes, depending on a range of aspects. M1 produces a pro-inflammatory feedback, while M2 is anti-inflammatory and fixings cells. In infection, macrophages polarize to M1 to eliminate virus and then to M2 to fix tissues. Excitement of macrophage polarization regulates immune function. Macrophage polarity plays a significant role in infections, inflammatory conditions, and hatreds; its monitoring is crucial for the prevention and therapy of condition. Consequently, this evaluation summarizes the governing mechanisms of macrophage polarization, suggesting that macrophages are a heterogeneous course of cells that can rapidly change their phenotype in feedback to exterior signals. Among them, TLR4 receptor sets off pro-inflammatory actions with MyD88 and TRIF signaling pathways.Notch signaling pathway controls mobile features and may contribute in macrophage apoptosis and M1/M2 polarization.JAK/STAT signaling path manages macrophage inflammatory feedbacks and advertises M1-type pro-inflammatory feedbacks and M2-type anti-inflammatory differentiation. Exhibits the function of macrophage polarization in inflammatory conditions such as sensitive bronchial asthma, atherosclerosis, and excessive weight. The crucial duty of macrophages in illness pathogenesis and inflammatory guideline is explored.

Phosphorylation-dependent activation of the bHLH transcription factor ICE1/SCRM promotes polarization of the Arabidopsis zygote.

In Arabidopsis thaliana, the asymmetric cell division (ACD) of the zygote gives rise to the embryo proper and an extraembryonic suspensor, respectively. This process is controlled by the ERECTA-YODA-MPK3/6 receptor kinase-MAP kinase-signaling pathway, which also orchestrates ACDs in the epidermis. In this context, the bHLH transcription factor ICE1/SCRM is negatively controlled by MPK3/6-directed phosphorylation. However, it is unknown whether this regulatory module is similarly involved in the zygotic ACD. We investigated the function of SCRM in zygote polarization by analyzing the effect of loss-of-function alleles and variants that cannot be phosphorylated by MPK3/6, protein accumulation, and target gene expression. Our results show that SCRM has a critical function in zygote polarization and acts in parallel with the known MPK3/6 target WRKY2 in activating WOX8. Our work further demonstrates that SCRM activity in the early embryo is positively controlled by MPK3/6-mediated phosphorylation. Therefore, the effect of MAP kinase-directed phosphorylation of the same target protein fundamentally differs between the embryo and the epidermis, shedding light on cell type-specific, differential gene regulation by common signaling pathways.

Acoustic Wake in a Singular Isothermal Profile: Dynamical Friction and Gravitational-wave Emission

We consider the motion of a circularly moving perturber in a self-gravitating, collisional system with a spherically symmetric density profile. We concentrate on the singular isothermal sphere, which, despite its pathological features, admits a simple polarization function in linear response theory. This allows us to solve for the acoustic wake trailing the perturber and the resulting dynamical friction, in the limit where the self-gravity of the response can be ignored. In a steady state and for subsonic velocities v p < c s , the dynamical friction torque Fφ∝vp3 is suppressed for perturbers orbiting in an isothermal sphere relative to the infinite, homogeneous medium expectation F φ ∝ v p . For highly supersonic motions, both expectations agree and are consistent with a local approximation to the gravitational torque. At fixed resolution (a given Coulomb logarithm), the response of the system is maximal for Mach numbers near the constant circular velocity of the singular isothermal profile. This resonance maximizes the gravitational-wave (GW) emission produced by the trailing acoustic wake. For an inspiral around a massive black hole of mass 106 M ⊙ located at the center of a (truncated) isothermal sphere, this GW signal could be comparable to the vacuum GW emission of a black hole binary at subnanohertz frequencies when the small black hole enters the Bondi sphere of the massive one. The exact magnitude of this effect depends on departures from hydrostatic equilibrium and on the viscosity present in any realistic astrophysical fluid, which are not included in our simplified description.

Study of halogen interactions in dichlorovinyldiazenes: Structural analysis, DFT simulation and molecular modeling

In recent years, our research group has synthesized about two hundred different dihalogenated vinyldiazenes. The analysis revealed that the type (conformation) of the compounds is the same-"bike stop", but the properties and nature of intermolecular interactions are different. The concepts of the nature of halogen-halogen relationships recommended by IUPAC (2013) do not explain the nature of the observed intermolecular interactions in the synthesized systems. In this paper, for the first time, using the examples of the compounds presented below, an algorithm is built for the relationship between the structure of synthesized compounds and their properties, and the nature of non-covalent interactions involving the chlorine atom.The molecules presented in this paper were studied by the DFT method using the hybrid potential of B3LYP with the Gaussian 09 software package. The extended basis 6-311++G(d,p) with polarization and diffusion functions was used for calculations. Conducted NBO analysis of atomic charge populations. Calculations of the structural parameters of the synthesized systems were carried out in order to study the reactivity, molecular properties and identify the nature of non-covalent interactions involving the halogen atom. It has been established that the Cl–C–Cl triad has a flat geometry and is capable of forming atypical non-covalent interactions both with each other and with various coplanar systems.

Adrenergic Regulation of Cardiac Macrophages: Heterogeneity, Plasticity, and Therapeutic Potential

Review Adrenergic Regulation of Cardiac Macrophages: Heterogeneity, Plasticity, and Therapeutic Potential Wenjing Xiang†, Mianli Wang†, Hualong Yu†, Haocheng Lu*, and Ying Wang* Department of Pharmacy, School of Medicine, South University of Science and Technology, Shenzhen 518055, China † These authors contributed equally to this work. * Correspondence: lhc@sustech.edu.cn (H.L.); wangy6@sustech.edu.cn (Y.W.) Received: 8 June 2024; Revised: 10 July 2024; Accepted: 15 July 2024; Published: 25 October 2024 Abstract: Cardiac macrophages play a crucial role in the development and progression of cardiovascular diseases, including myocardial infarction, cardiac hypertrophy, and myocarditis. Macrophages are plastic cells that change their polarization states and functions in response to alterations in the surrounding environment. This process is deeply involved in various biological processes such as inflammation, tissue remodeling and repairing, exacerbating or mitigating the diseases progression. Thus, macrophages have emerged as potential therapeutic targets for multiple cardiac diseases. Upon sympathetic activation, adrenergic/ cyclic adenosine monophosphate (cAMP) signaling axis markedly modulates macrophages polarization and functions. It has been well-established that the intracellular cAMP is highly compartmentalized in cardiomyocytes. However, the spatiotemporal regulation of cAMP in cardiac macrophages and its implications in macrophage-driven cardiac diseases remain to be elucidated. In this review, we focus on the adrenergic/cAMP regulation of macrophage plasticity and function in the heart and discuss potentials and challenges of targeting the adrenergic/cAMP axis for cardiac diseases.

Cluster Assembly Dynamics Drive Fidelity of Planar Cell Polarity Polarization.

The planar cell polarity (PCP) signaling pathway polarizes epithelial cells in the tissue plane by segregating distinct molecular subcomplexes to opposite sides of each cell, where they interact across intercellular junctions to form asymmetric clusters. The role of clustering in this process is unknown. We hypothesized that protein cluster size distributions could be used to infer the underlying molecular dynamics and function of cluster assembly and polarization. We developed a method to count the number of monomers of core PCP proteins within individual clusters in live animals, and made measurements over time and space in wild type and in strategically chosen mutants. The data demonstrate that clustering is required for polarization, and together with mathematical modeling provide evidence that cluster assembly dynamics dictate that larger clusters are more likely to be strongly asymmetric and correctly oriented. We propose that cluster assembly dynamics thereby drive fidelity of cell- and tissue-level polarization.

Syn vs. Anti? What Controls Addition Stereochemistry in Chlorolactonization.

The stereochemistry of the uncatalyzed chlorolactonization of 4-phenylpent-4-enoic acid at room temperature was examined to probe the reaction's intrinsic diastereoselectivities as a function of chlorenium ion donor, solvent polarity, and reactant concentration ranges. Kinetic studies using Variable Time Normalization Analysis (VTNA) revealed differing reaction orders for the syn and anti alkene addition processes. Aided and illustrated by quantum chemical modeling, this detailed mechanistic analysis of the substrate's intrinsic chlorolactonization reactions points to concerted AdE3-type paths for both syn and anti additions. By illuminating the factors selecting for syn- vs anti-addition paths, the results provide key reference points for future studies of stereocontrol in halofunctionalization reactions.