Loop Axis Research Articles

Analysis of the far-field radiation pattern by a current loop in hyperbolic material

In this article, we investigate the radiations from a current loop in hyperbolic materials. To encounter the arbitrary orientation of the loop, the results are presented when the loop axis is aligned parallel and perpendicular to the optic axis. Closed-form expressions as well as numerical results are presented for both ordinary and extraordinary waves. The results indicate a strong dependence on the size of the loop, in contrast to the case of uniaxial dielectric materials. When the loop axis is parallel to the optic axis, the pattern is quite similar to that of uniaxial dielectric materials; however, a significant change in the pattern is observed when the optic axis turns perpendicular to the loop axis. The results show a significant role of the size of the loop in the hyperbolic material as compared to the uniaxial dielectric material.

Non-thermal broadening of coronal lines in a 3D MHD loop model

ABSTRACT Observed spectral profiles of emission lines from the corona are found to have widths exceeding the thermal line width. To investigate the physical mechanism, we run a 3D magnetohydrodynamics model of a single, straightened loop in which we partially resolve turbulent motions that form in response to the driving by self-consistently evolving magneto-convection in the photosphere. The convective motions shear and twist the magnetic field lines, leading to heating. From the model, we synthesize spectral profiles of emission lines forming at temperatures around and above 1 MK. The coronal heating process generates a range of velocity amplitudes and directions structured on a scale much smaller than the resolving power of current instruments, leading to a broadening of the spectral lines. Our model includes the mass exchange between corona and chromosphere, thus we also capture flows parallel to the loop axis. We find that the spectral lines show a non-thermal line broadening roughly consistent with observations for a viewing angle perpendicular to the axis. The broadening through field-parallel flows is comparable, although slightly smaller. The line broadening is independent of the instrument resolution for a perpendicular line of sight (LOS). We can connect the non-thermal line broadening to heating events and flows. While small-scale velocities along the LOS are mainly responsible for the broadening observed perpendicular to the loop, chromospheric evaporation is important for the line broadening observed along the loop. The model reproduces observed values for non-thermal line widths. In the model, these result from continuous driving by magnetoconvection, without imposing driving motions or starting from an already braided field.

LncRNA LINK-A Remodels Tissue Inflammatory Microenvironments to Promote Obesity.

High-fat diet (HFD)-induced obesity is a crucial risk factor for metabolic syndrome, mainly due to adipose tissue dysfunctions associated with it. However, the underlying mechanism remains unclear. This study has used genetic screening to identify an obesity-associated human lncRNA LINK-A as a critical molecule bridging the metabolic microenvironment and energy expenditure in vivo by establishing the HFD-induced obesity knock-in (KI) mouse model. Mechanistically, HFD LINK-A KI mice induce the infiltration of inflammatory factors, including IL-1β and CXCL16, through the LINK-A/HB-EGF/HIF1α feedback loop axis in a self-amplified manner, thereby promoting the adipose tissue microenvironment remodeling and adaptive thermogenesis disorder, ultimately leading to obesity and insulin resistance. Notably, LINK-A expression is positively correlated with inflammatory factor expression in individuals who are overweight. Of note, targeting LINK-A via nucleic acid drug antisense oligonucleotides (ASO) attenuate HFD-induced obesity and metabolic syndrome, pointing out LINK-A as a valuable and effective therapeutic target for treating HFD-induced obesity. Briefly, the results reveale the roles of lncRNAs (such as LINK-A) in remodeling tissue inflammatory microenvironments to promote HFD-induced obesity.

Modulation depth of the gyrosynchrotron emission as an identifier of fundamental sausage modes

Aims. We aim to study the intensity, the modulation depth, and the mean modulation depth of the gyrosynchrotron (GS) radiation as a function of the frequency and the line of sight (LOS) in fast sausage modes. Methods. By solving the 2.5D magnetohydrodynamics (MHD) ideal equations of a straight coronal loop considering the chromosphere and with typical flaring plasma parameters we analyse the wavelet transform of the density and the GS emission for different radio frequencies and different spatial resolutions, given impulsive and general perturbations with energies in the microflare range. Results. A wavelet analysis performed over the GS radiation emission showed that a fast fundamental sausage mode of ∼7 s with a first harmonic mode of 3 s developed, for all the initial energy perturbations used. For both the high spatial resolution (central pixel integration) and the low spatial resolution (entire loop integration), the larger the radio frequency, the larger the modulation depth. However, high- and low-resolution integrations differ in that the larger the LOS angle with respect to the loop axis, the larger and smaller the modulation depth, respectively. Conclusions. Fast MHD modes triggered by instantaneous energy depositions of the order of a microflare energy are able to reproduce deep intensity modulation depths in radio emission as observed in solar events. As the trends of the GS emission previously obtained for a linear and forced oscillation remain present when analysing a more general context, considering the chromosphere and where the sausage mode is triggered by an impulsive, non-linear perturbation, it seems that the behaviour found can be used as observational identifiers of the presence of sausage modes with respect to other quasi-periodic pulsation features. It can be inferred from this that finite-amplitude sausage modes have the potential to generate the observed deep modulation depths.

Three-Dimensional Reconstruction of Coronal Features: A Python Tool for Geometric Triangulation

The determination of the three-dimensional (3D) geometry of coronal features is important for understanding the magnetic structuring of the solar atmosphere. In this context, the length of a coronal loop, which is subject to standing transverse oscillations, is a crucial parameter in coronal seismology for the correct estimation of the phase speed of the wave and, consequently, of the Alfvén speed and coronal magnetic-field strength. Simultaneous space-based observations of the solar corona from different vantage points, e.g. one from the Solar Dynamics Observatory (SDO) and the second from the Solar TErrestrial RElations Observatory (STEREO), have permitted the reconstruction of the geometry of coronal loops. Nisticò, Verwichte, and Nakariakov (Entropy15, 4520, 2013) proposed a method based on principal component analysis for fitting an ensemble of 3D points that sample a coronal loop. This method was shown to retrieve easily the main geometric parameters that define a loop, such as the loop axes and the loop plane. In this article, an extension of that work is presented that includes a Python tool for performing geometric triangulation of coronal features seen by two different observers.

Coronal loop kink oscillation periods derived from the information of density, magnetic field, and loop geometry

Context. Coronal loop oscillations can be triggered by solar eruptions, for example, and are observed frequently by the Atmospheric Imaging Assembly (AIA) on board Solar Dynamics Observatory (SDO). The Helioseismic and Magnetic Imager (HMI) on board SDO offers us the opportunity to measure the photospheric vector magnetic field and carry out solar magneto-seismology (SMS). Aims. By applying SMS, we aim to verify the consistency between the observed period and the one derived from the information of coronal density, magnetic field, and loop geometry, that is, the shape of the loop axis. Methods. We analysed the data of three coronal loop oscillation events detected by SDO/AIA and SDO/HMI. First, we obtained oscillation parameters by fitting the observational data. Second, we used a differential emission measure (DEM) analysis to diagnose the temperature and density distribution along the coronal loop. Subsequently, we applied magnetic field extrapolation to reconstruct the three-dimensional magnetic field and then, finally, used the shooting method to compute the oscillation periods from the governing equation. Results. The average magnetic field determined by magnetic field extrapolation is consistent with that derived by SMS. A new analytical solution is found under the assumption of exponential density profile and uniform magnetic field. The periods estimated by combining the coronal density and magnetic field distribution and the associated loop geometry are closest to the observed ones, and are more realistic than when the loop geometry is regarded as being semi-circular or having a linear shape. Conclusions. The period of a coronal loop is sensitive to not only the density and magnetic field distribution but also the loop geometry.

Observations of Instability-driven Nanojets in Coronal Loops

The recent discovery of nanojets by Antolin et al. represents magnetic reconnection in a braided field, thus clearly identifying reconnection-driven nanoflares. Due to their small scale (500 km in width, 1500 km in length) and short timescales (<15 s), it is unclear how pervasive nanojets are in the solar corona. In this paper, we present Interface Region Imaging Spectrograph and Solar Dynamics Observatory observations of nanojets found in multiple coronal structures, namely, in a coronal loop powered by a blowout jet, and in two other coronal loops with coronal rain. In agreement with previous findings, we observe that nanojets are accompanied by small nanoflare-like intensity bursts in the (E)UV, have velocities of 150–250 km s−1 and occur transversely to the field line of origin, which is sometimes observed to split. However, we find a variety of nanojet directions in the plane transverse to the loop axis. These nanojets are found to have kinetic and thermal energies within the nanoflare range, and often occur in clusters. In the blowout jet case study, the Kelvin–Helmholtz instability (KHI) is directly identified as the reconnection driver. For the other two loops, we find that both, KHI and Rayleigh–Taylor instability (RTI) are likely to be the drivers. However, we find that KHI and RTI are each more likely in one of the other two cases. These observations of nanojets in a variety of structures and environments support nanojets being a general result of reconnection that are driven here by dynamic instabilities.

A New Technique to Diagnose the Geomagnetic Field Based on a Single Circular Current Loop Model

AbstractThe geomagnetic field originates from interior dynamo currents and can be approximated well by a simple dipolar field in the vicinity of Earth's surface. Given that the dipolar field is induced by a current loop, it is possible to invert the loop parameters by tracing the sampled magnetic field geometry. Drawing on the analysis of field geometric structure with sampled field dataset, we develop, in this study, a new technique to invert the interior current source, which is based on a single circular current loop model. Unlike previous studies, this technique has the ability to separate and solve the optimal loop parameters successively, including the location of the loop center, the loop axis, the radius, and the carried electric current. Applications to the International Geomagnetic Reference Field and the sampled magnetic field dataset by the spacecraft of the Swarm mission demonstrate that our technique‐derived loop center, loop axis, and magnetic moment are consistent with previous estimations by the eccentric dipole model, which shows the reasonability and effectiveness of this technique. Moreover, our technique can be reduced to fit an eccentric dipole model and is particularly useful for inversions of the geometry of interior current sources. Thus, it could be applied widely in the fields of planetary magnetism and palaeomagnetism. Further applications and constraints are discussed, with some cautions given.

Chromosome Organization in Early Meiotic Prophase.

One of the most fascinating aspects of meiosis is the extensive reorganization of the genome at the prophase of the first meiotic division (prophase I). The first steps of this reorganization are observed with the establishment of an axis structure, that connects sister chromatids, from which emanate arrays of chromatin loops. This axis structure, called the axial element, consists of various proteins, such as cohesins, HORMA-domain proteins, and axial element proteins. In many organisms, axial elements are required to set the stage for efficient sister chromatid cohesion and meiotic recombination, necessary for the recognition of the homologous chromosomes. Here, we review the different actors involved in axial element formation in Saccharomyces cerevisiae and in mouse. We describe the current knowledge of their localization pattern during prophase I, their functional interdependence, their role in sister chromatid cohesion, loop axis formation, homolog pairing before meiotic recombination, and recombination. We also address further challenges that need to be resolved, to fully understand the interplay between the chromosome structure and the different molecular steps that take place in early prophase I, which lead to the successful outcome of meiosis I.

Kink Oscillations in Solar Coronal Loops with Elliptical Cross Sections. I. The Linear Regime

Abstract The cross sections of solar coronal loops are suggested to be rarely circular. We examine linear kink oscillations in straight, density-enhanced, magnetic cylinders with elliptical cross sections by solving the three-dimensional magnetohydrodynamic equations from an initial-value-problem perspective. Motivated by relevant eigenmode analyses, we distinguish between two independent polarizations, one along the major axis (the M-modes) and the other along the minor one (the m-modes). We find that, as happens for coronal loops with circular cross sections, the apparent damping of the transverse displacement of the loop axis is accompanied by the accumulation of transverse Alfvénic motions and the consequent development of small scales therein, suggesting the robustness of the concepts of resonant absorption and phase mixing. In addition, two stages can in general be told apart in the temporal evolution of the loop displacement: a Gaussian time dependence precedes an exponential one. For the two examined density ratios between loops and their surroundings, the periods of the M-modes (m-modes) tend to increase (decrease) with the major-to-minor-half-axis ratio, and the damping times in the exponential stage for the M-modes tend to exceed their m-mode counterparts. This is true for the two transverse profiles we examine. However, the relative magnitudes of the damping times in the exponential stage for different polarizations depend on the specification of the transverse profile or the density contrast. The applications of our numerical findings are discussed in the context of coronal seismology.

4-Aminobiphenyl suppresses homologous recombination repair by a reactive oxygen species-dependent p53/miR-513a-5p/p53 loop

4-Aminobiphenyl (4-ABP), a well-known human carcinogen, can cause oxidative DNA damage and induce miR-513a-5p. However, the interplay between miR-513a-5p and DNA damage remains unclear. In our result of ChIP assay, we speculated that p53 as transcription factor could regulate miR-513a-5p expression. In addition, we found that miR-513a-5p-induced by 4-ABP could suppress p53 expression and HR repair activity. On the other hand, the levels of p53, miR-513a-5p, and γH2AX were attenuated by 5 mM N-acetyl-l-cysteine (NAC) pretreatment, indicating that the reactive oxygen species (ROS)-dependent p53-miR-513a-5p was involved in DSB repair in 4-ABP-treated cells. These findings indicated that the ROS/p53/miR-513a-5p/p53 loop axis plays a relevant role in regulating HR repair which may facilitate our understanding of molecular mechanisms regarding how miR-513a-5p impacts DSB repair in 4-ABP-treated cells.

Cross Sections of Coronal Loop Flux Tubes

Abstract Coronal loops reveal crucial information about the nature of both coronal magnetic fields and coronal heating. The shape of the corresponding flux tube cross section and how it varies with position are especially important properties. They are a direct indication of the expansion of the field and of the cross-field spatial distribution of the heating. We have studied 20 loops using high spatial resolution observations from the first flight of the Hi-C rocket experiment, measuring the intensity and width as a function of position along the loop axis. We find that intensity and width tend to either be uncorrelated or to have a direct dependence, such that they increase or decrease together. This implies that the flux tube cross sections are approximately circular under the assumptions that the tubes have nonnegligible twist and that the plasma emissivity is approximately uniform along the magnetic field. The shape need not be a perfect circle and the emissivity need not be uniform within the cross section, but subresolution patches of emission must be distributed quasi-uniformly within an envelope that has an aspect ratio of order unity. This raises questions about the suggestion that flux tubes expand with height, but primarily in the line-of-sight direction so that the corresponding (relatively noticeable) loops appear to have roughly uniform width, a long-standing puzzle. It also casts doubt on the idea that most loops correspond to simple warped sheets, although we leave open the possibility of more complex manifold structures.

Non-equilibrium Ionization Effects on Extreme-ultraviolet Emissions Modulated by Standing Sausage Modes in Coronal Loops

Abstract Forward-modeling the emission properties in various passbands is important for confidently identifying magnetohydrodynamic waves in the structured solar corona. We examine how non-equilibrium ionization (NEI) affects the extreme-ultraviolet (EUV) emissions modulated by standing fast sausage modes (FSMs) in coronal loops, taking the Fe ix 171 Å and Fe xii 193 Å emission lines as examples. Starting with the expressions for linear FSMs in straight cylinders, we synthesize the specific intensities and spectral profiles for the two spectral lines by incorporating the self-consistently derived ionic fractions in the relevant contribution functions. We find that relative to the case where equilibrium ionization (EI) is assumed, NEI considerably impacts the intensity modulations, but shows essentially no effect on the Doppler velocities or widths. Furthermore, NEI may affect the phase difference between intensity variations and those in Doppler widths for Fe xii 193 Å when the line of sight is oblique to the loop axis. While this difference is 180° when EI is assumed, it is ∼90° when NEI is incorporated for the parameters we choose. We conclude that in addition to viewing angles and instrumental resolutions, NEI further complicates the detection of FSMs in spectroscopic measurements of coronal loops in the EUV passband.

Particle Acceleration by Induced Electric Fields in Course of Electric Current Oscillations in Coronal Magnetic Loops

A mechanism for acceleration of electrons driven by the oscillations of the electric current in solar magnetic loops is considered. The magnetic loop is presented as an equivalent RLC-circuit with the electric current generated by convective motions in the photosphere. Eigen oscillations of the current in a loop induce the electric field directed along to the loop axis. It is shown that pulsating type III bursts and the sudden reductions that occur in the course of type IV continuum in solar flares provide evidence for acceleration and storage of energetic electrons in the coronal magnetic loops. Energization rate of electrons accelerated by sub-Dreicer electric field are determined. The energy spectra of fast electrons under both intermediate and strong regimes of pitch-angle diffusion are discussed. Two examples of the electron acceleration in the pulsating type III solar bursts are considered. We also discuss the efficiency of suggested mechanism as compared with the electron acceleration during 5-min photospheric oscillations and with the acceleration driven by the magnetic Rayleigh-Taylor instability.

Double plasma-resonance surfaces in flare loops and radio zebra emission

Aims. The zebra structures observed in radio waves during solar flares are some of the most important structures used as diagnostics of solar flare plasmas. We here not only analyze the so-called double plasma-resonance (DPR) surfaces, but also estimate the effects of their form on the size of the zebra sources and brightness temperature.Methods. To compute the DPR surfaces, we used numerical and analytical methods.Results. We found that except for the case of a constant magnetic field across the loop, the DPR surfaces deviate from the constant plasma density surfaces. We found that the regime with a finite height scale has three forms of resonance surfaces depending on the magnetic field variation across the loop. This magnetic field variation also determines if in the generated zebra structure, an increase in gyro-harmonic number leads to an increase or decrease of the zebra stripe frequency. In the case with an infinite height scale, the resonance surfaces are parallel to the loop axis. Furthermore, we found that for highly polarized zebra structures that are generated at DPR surfaces close to the plasma frequency, the zebra emission is limited to the narrow escaping cone and the emitting source area increases with increasing viewing angle compared to the loop axis. Moreover, with increasing deviation of the DPR surfaces from those of constant density surfaces, the frequency bandwidth of the DPR emission increases and can cause the zebra stripes to overlap, which limits the zebra generation. For the zebra structures observed on 14 February 1999, 6 June 2000, and 1 August 2010 and the observed view perpendicular to the loop axis, we estimated that the brightness temperature is 3.67 × 1014K, 6.58 × 1013K, and 7.35 × 1015K, respectively. These brightness temperatures are much lower than those derived for the view along the loop axis (up to 1017K), and thus are more realistic. The area of the emitting source for coronal loops in the view perpendicular to the loop axis can be larger by several orders of magnitude than that in the view along the loop axis.

Whistler modes in highly nonuniform magnetic fields. II. Propagation in three dimensions

In a large laboratory plasma, the properties of whistler modes are investigated in highly nonuniform magnetic fields. In an extension to previous measurements in two dimensions (2D), the present work shows new phenomena such as wave splitting in the third dimension and shedding of cross-field helicon-like modes. Three-dimensional (3D) data also permit the correct calculations of the field derivatives (∇⋅, ∇×), helicity density (J ⋅ B), Hall electric fields, phase and energy flow, and out-of-plane field structures, which are not visible from 2D data. Novel findings are the loss of the angular momentum of an m = 1 helicon mode, the splitting of a single wave packet into two wave packets in the direction of the loop axis, and the shedding of perpendicular whistler modes with angular momentum. The 3D effects cannot be explained by nonuniformities in the density and the 2D ambient magnetic field B0. They may arise from the conservation of orbital angular momentum whose direction changes along a curved magnetic field. It results in a precessional motion which creates asymmetries in the third dimension. Further effects are the interference of oppositely propagating helicon modes on circular field lines which creates linear polarization near the conjugate point of the antenna. Detached whistler modes are excited in the oscillating near-zone field. The waves propagate nearly perpendicular to the ambient field. The field polarization is right-hand circular around the oblique wave vector k but not around B0. Since the wave field is force-free the wave magnetic field lines form twisted field lines or writhed flux tubes. From streamlines of hodogram normals, it is shown that the wave exhibits a helical phase flow similar to helicon modes. These observations show the complexity of whistler modes in nonuniform magnetic fields, even under the simplest conditions of a uniform, unbounded plasma and linear waves. The results may be of interest to other laboratory plasmas and space plasmas in nonuniform magnetic fields. Meaningful comparisons require 3D field data which are rarely available.

Detection of the Second Harmonic of Decay-less Kink Oscillations in the Solar Corona

Abstract EUV observations of a multi-thermal coronal loop, taken by the Atmospheric Imaging Assembly of the Solar Dynamics Observatory, which exhibits decay-less kink oscillations are presented. The data cube of the quiet-Sun coronal loop was passed through a motion magnification algorithm to accentuate transverse oscillations. Time–distance maps are made from multiple slits evenly spaced along the loop axis and oriented orthogonal to the loop axis. Displacements of the intensity peak are tracked to generate time series of the loop displacement. Fourier analysis on the time series shows the presence of two periods within the loop: minutes and minutes. The longer period component is greatest in amplitude at the apex and remains in phase throughout the loop length. The shorter period component is strongest further down from the apex on both legs and displays an anti-phase behavior between the two loop legs. We interpret these results as the coexistence of the fundamental and second harmonics of the standing kink mode within the loop in the decay-less oscillation regime. An illustration of seismological application using the ratio P 1/2P 2 ∼ 0.7 to estimate the density scale height is presented. The existence of multiple harmonics has implications for understanding the driving and damping mechanisms for decay-less oscillations and adds credence to their interpretation as standing kink mode oscillations.

Apex Dips of Experimental Flux Ropes: Helix or Cusp?

Abstract We present a new theory for the presence of apex dips in certain experimental flux ropes. Previously such dips were thought to be projections of a helical loop axis generated by the kink instability. However, new evidence from experiments and simulations suggest that the feature is a 2D cusp rather than a 3D helix. The proposed mechanism for cusp formation is a density pileup region generated by nonlinear interaction of neutral gas cones emitted from fast-gas nozzles. The results indicate that density perturbations can result in large distortions of an erupting flux rope, even in the absence of significant pressure or gravitational forces. The density pileup at the apex also suppresses the m = 1 kink mode by acting as a stationary node. Consequently, more accurate density profiles should be considered when attempting to model the stability and shape of solar and astrophysical flux ropes.

Acceleration and Storage of Energetic Electrons in Magnetic Loops in the Course of Electric Current Oscillations

A mechanism of electron acceleration and storage of energetic particles in solar and stellar coronal magnetic loops, based on oscillations of the electric current, is considered. The magnetic loop is presented as an electric circuit with the electric current generated by convective motions in the photosphere. Eigenoscillations of the electric current in a loop induce an electric field directed along the loop axis. It is shown that the sudden reductions that occur in the course of type IV continuum and pulsating type III observed in various frequency bands (25 – 180 MHz, 110 – 600 MHz, 0.7 – 3.0 GHz) in solar flares provide evidence for acceleration and storage of the energetic electrons in coronal magnetic loops. We estimate the energization rate and the energy of accelerated electrons and present examples of the storage of energetic electrons in loops in the course of flares on the Sun or on ultracool stars. We also discuss the efficiency of the suggested mechanism as compared with the electron acceleration during the five-minute photospheric oscillations and with the acceleration driven by the magnetic Rayleigh–Taylor instability.

PP.14.34] ELECTROCARDIOLOGIC P AND QRS PARAMETERS AS THE RISK SIGNS FOR FUTURE ATRIAL FIBRILLATION IN HYPERTENSIVE PATIENTS

Objective: The simple mode of identifying HT patients at risk for atrial fibrillation (AF) is important in practical clinical health care. Some non-invasive ECG and VCG parameters (in P and QRS waves and loops) are routinely available for ECG measurements. Especially, P wave/P loop values reflect the abnormal electrophysiologic status in atrial myocardium. Design and method: We studied 224 HT patients in sinus rhythm (SR): group I (n = 106, without documented AF), group II (n = 107, with well-documented paroxysmal AF), group III (n = 11, HT patients after successfull radiofrequence ablation of AF). ECG parameters were evaluated: (1) heart rate in SR (HR), ECG P wave and QRS, duration, non-filtered and after Hi-Res filtering: nPd, nQRSd, fPd, fQRSd, (2) VCG parameters of P, QRS axes, (3) angle between VCG loop axes P-QRS and QRS-T; (4) EchoCG parameters: LA dimension, LVEF, IVSd, PWd. Results: [1] In group II and III the non-filtered parameters (nPd, fPd) and filtered parameters (fPd, fQRSd) were significantly longer than in group I (for nPd: 135.0 ms, 145.0 ms vs.129.0 ms,p < 0.05; for nQRSd: 105.0 ms, 113.0 ms vs. 99.0 ms, p < 0.01; for fPd: 143.0 ms, 157.0 ms vs. 134.0 ms, p < 0.005; for fQRSd: 119.0 ms, 125.0 ms vs. 115.0 ms, p < 0.05). [2] P loop axis is significantly higher in group II and III vs. group I (+50.0 gr., +55.0 gr. vs.+47.0 gr.; p < 0.01). [3] Angle P-QRS is significantly higher in group II and III vs. group I (46.5 gr., 42.0 gr. vs. 24.3 gr; p < 0.005). [4] EchoCG parameters were not significantly different. (LA dimensions FOR groups. I, II, III: 40.0 mm, 42.7 mm, 42.0 mm, ns.). Conclusions: HT patients with verified pFA in documentation have more abnormal P and QRS wave/loop parameters than HT patients without history of pFA. The most informative ECG factors for possible future pFA are: fPd, fQRSd, angle between loop axes P-QRS. ECG and VCG parameters (non-filtered and especially after High-Res analysis) have the potential to improve the risk stratification for possible pFA or pFLA. These cross-sectional results is necessary to confirm with futher follow-up (after 12 months and later).