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The scaling of galaxy properties with halo mass suggests that feedback loops regulate star formation, but there is no consensus yet about how those feedback loops work. To help clarify discussions of galaxy-scale feedback, Paper I presented a very simple model for supernova feedback that it called the minimalist regulator model. This follow-up paper interprets that model and discusses its implications. The model itself is an accounting system that tracks all of the mass and energy associated with a halo's circumgalactic baryons—the central galaxy's atmosphere. Algebraic solutions for the equilibrium states of that model reveal that star formation in low-mass halos self-regulates primarily by expanding the atmospheres of those halos, ultimately resulting in stellar masses that are insensitive to the mass-loading properties of galactic winds. What matters most is the proportion of supernova energy that couples with circumgalactic gas. However, supernova feedback alone fails to expand galactic atmospheres in higher-mass halos. According to the minimalist regulator model, an atmospheric contraction crisis ensues, which may be what triggers strong black hole feedback. The model also predicts that circumgalactic medium properties emerging from cosmological simulations should depend largely on the specific energy of the outflows they produce, and we interpret the qualitative properties of several numerical simulations in light of that prediction. [ABSTRACT FROM AUTHOR]

The primary objective of this paper is to identify periodic orbits for solar sails within the oblate Earth-Moon Circular Restricted Three-Body Problem (CR3BP). Incorporating solar acceleration into the Earth-Moon system modifies the governing orbital equations, transforming the traditional CR3BP from an autonomous to a non-autonomous system. As a result, the procedure for identifying periodic orbits diverges from the conventional autonomous CR3BP method. Thus, this paper introduces a novel methodology to identify new periodic Halo and Lyapunov orbits within the non-autonomous CR3BP. Our proposed approach comprises four hierarchical steps: first, a surface of section simulation (Poincaré map) is conducted to obtain an initial approximation of the orbital state vector within the autonomous CR3BP. Second, a periodic orbit correction algorithm is developed using the autonomous CR3BP equations to acquire precise initial conditions. In the third step, initial conditions for solar sail periodic orbits are derived by applying the initial conditions of autonomous CR3BP periodic orbits as inputs to the periodic orbit correction algorithm, which is now executed using non-autonomous CR3BP equations. In the final step, a family of orbits is generated by gradually increasing the sail's characteristic acceleration. Our work addresses limitations in previous studies that relied on initial guesses derived solely from the unperturbed autonomous CR3BP reported in earlier research, which often resulted in the missing of numerous solar sail periodic orbits in the non-autonomous system. This approach enables the discovery of new periodic orbits within the Earth-Moon system, accounting for perturbations from the oblate primaries, including zonal harmonic terms from j 2 to j 6 . The methodology is validated through simulations of solar sail Lyapunov and Halo orbits, offering a comprehensive understanding of the Earth-Moon CR3BP under non-autonomous conditions. [ABSTRACT FROM AUTHOR]

Many seabirds congregate in large colonies for breeding, a time when they are central place foragers. An influential idea in seabird ecology posits that competition during breeding results in an area of reduced prey availability around colonies, a phenomenon known as Ashmole's halo, and that this limits colony size. This idea has gained empirical support, including the finding that species coexisting within a colony might be able to do so by foraging on a single prey species but at different distances. Here, we provide a comprehensive mathematical model for central place foragers exploiting a single prey in a two-dimensional environment, where the prey distribution is the result of intrinsic birth and death, movement in space, and mortality due to foraging birds (we also consider a variant tailored toward colonial social insects). Bird predation at different distances occurs according to an ideal free foraging distribution that maximizes prey delivery under flight and search costs. We fully characterize the birds' ideal free distribution and the prey distribution it generates. Our results show that prey depletion halos around breeding colonies are a robust phenomenon and that the birds' ideal free distribution is sensitive to prey movement. Furthermore, coexistence of several seabird species on a single prey easily emerges through behavioral niche partitioning whenever trait differences between species entail trade-offs between efficiently exploiting a scarce prey close to the colony and a more abundant prey far away. Such behavioral-based coexistence-inducing mechanism should generalize to other habitat and diet choice scenarios. [ABSTRACT FROM AUTHOR]

Sprite halos are transient luminous phenomena in the lower ionosphere triggered by tropospheric lightning. The effect of removed charge distributions on sprite halos has not been sufficiently discussed. A three-dimensional (3D) quasi-electrostatic (QES) field model was developed in this paper, including the ionospheric nonlinear effect and optical emissions. Simulation results show that, for a total charge of 150 C removed within 1 ms with different spatial distributions, higher altitudes of charge removal lead to stronger electric fields and increase sprite halos' emission intensities. The non-axisymmetric horizontal distribution of charge affects mesospheric electric fields, and the corresponding scales and intensities of emissions vary with observation orientations. Considering the tilted dipole charge structure due to wind shear, the generated electric field and the corresponding position of sprite halos shift accordingly with the tropospheric removed charge, providing an explanation for the horizontal displacement between sprite halos and the parent lightning. [ABSTRACT FROM AUTHOR]

The microstructure of the halo ring has been studied in quenched and partitioned (Q&P) steel resistance spot welds. The TEM and EBSD characterizations revealed the presence of an upper bainitic microstructure in the halo ring of the three-sheet stack-up welds. Stalking faults accompanied by nano-twins were identified surrounding the cementite. Diffusion of carbon towards the molten weld pool during solidification led to the formation of bainite at the fusion boundary, triggered the localized softening. [ABSTRACT FROM AUTHOR]

Solar type V radio bursts are associated with type III bursts. Several processes have been proposed to interpret the association, electron distribution, and emission. We present the observation of a unique type V event observed by e-CALLISTO on 7 May 2021. The type V radio emission follows a group of U bursts. Unlike the unpolarized U bursts, the type V burst is circularly polarized, leaving room for a different emission process. Its starting edge drifts to higher frequency four times slower than the descending branch of the associated U burst. The type V processes seem to be ruled by electrons of lower energy. The observations conform to a coherent scenario where a dense electron beam drives the two-stream instability (causing type III emission) and, in the nonlinear stage, becomes unstable to another instability, previously known as the electron firehose instability (EFI). The secondary instability scatters some beam electrons into velocities perpendicular to the magnetic field and produces, after particle loss, a trapped distribution prone to electron cyclotron masering (ECM). A reduction in beaming and the formation of an isotropic halo are predicted for electron beams continuing to interplanetary space, possibly observable by Parker Solar Probe and Solar Orbiter. [ABSTRACT FROM AUTHOR]

In this research paper we investigated the halo coronal mass ejections and sunspot number during the period December 2019 to December 2023 for the rising phase of solar cycle 25. The SOHO/LASCO instrument observed 145 HCMEs during this period. We selected 145 halo CMEs and the associated flares, SSN and Dst. The HCME is found to be significantly faster and more energetic than the other CME. During solar maximum, HCME occur more frequently. Here we have considered all the frontside disk halos, frontside limb halos and the backside halos of the sun. These halos are classified according to their source location. Mostly the frontside disk halos are more geoeffective. For 70% (7/10) of the halo CMEs associated with X class flares have a speed greater than 1000 km/s. The daily sunspot number (SSN) and the yearly mean total sunspot number are taken into consideration for our study. The study of sunspot numbers is essential for planning space-related activities, particularly for low Earth orbiting spacecraft. Geoeffectiveness is the capacity of HCMEs to induce geomagnetic storms. The "Dst (Disturbance storm time) index" is one geomagnetic metric that is used to measure this. We categorized geoeffective halos into three groups: strongly geoeffective (Strong-GE, Dst < −100 nT), moderately geoeffective (Moderate-GE, −100 < Dst ≤ −50 nT), and weakly geoeffective (Weak-GE, Dst > −50 nT). Only 3.44% of halo CMEs were strongly geoeffective, and all of these were disk halos. The NW quadrant has the highest number of events throughout the research period of December 2019–December 2023. In this paper, we illustrate how the parameters of halo coronal mass ejections, sunspots and Dst can be used for space weather effects, evaluating geoeffectiveness, and auroras. [ABSTRACT FROM AUTHOR]

Sprite halos are diffuse glow discharges in the D-region ionosphere triggered by the quasi-electrostatic (QES) fields of lightning discharges. A three-dimensional (3D) QES model is adopted to investigate the effect of ionospheric electron density on sprite halos. The electron density is described by an exponential formula, parameterized by reference height (h') and sharpness (β), and the local inhomogeneity has a Gaussian density distribution. Simulation results indicate that the reference height and steepness of the nighttime electron density affect the penetration altitudes and amplitudes of normalized electric fields, as well as the altitudes and intensities of the corresponding sprite halos optical emissions. A comparison of the daytime and nighttime conditions demonstrates that the daytime electron density profile is not favorable for generating sprite halos emissions. Furthermore, the pre-existing electron density inhomogeneities lead to enhanced local electric fields and optical emissions, potentially offering a plausible explanation for the horizontal displacement between sprites and their parent lightning, as well as their clustering. [ABSTRACT FROM AUTHOR]

Figs (Ficus carica L.) are widely cultivated throughout the world owing to their excellent medical and edible value. In October 2021, we discovered a new leaf target-spot disease associated with the common fig in China. It is necessary to identify the causal agent, as it seriously affects the normal growth of figs and reduces their economic value. The initially infected leaves displayed light yellow lesions between the leaf veins. Under conditions of suitable temperature and humidity, the lesions expanded rapidly with light brown in the middle and dark brown at the margin accompanied by a yellow halo, and typical target holes appeared in the centre of the lesions. Three filamentous fungi were isolated from infected leaves, among which the isolate WHG-3 exerted the strongest virulence in vitro. Its newly grown mycelia were white and then gradually turned to dark grey. The conidia were hyaline, spindle-shaped or oval, with thin cell walls. Phylogenetic analyses based on the ITS, tef-1 and tub2 gene sequences verified that the isolates WHG-3, WHG-4 and WHG-5 were Neofusicoccum parvum. To the best of our knowledge, this is the first report that N. parvum causes leaf target-spot on Ficus carica L. in China. [ABSTRACT FROM AUTHOR]

There is limited information available on pressure‐related neonatal nasal injuries. We present three neonates born with erythema and purpura of the nasal tip that subsequently ulcerated, then evolved into a thick eschar. Each healed well with conservative management but left behind significant scarring. The sharp demarcation and location of the lesions were suggestive of hypoxic tissue damage akin to halo scalp ring alopecia. Further investigation is necessary to elucidate the etiology and optimal management of this condition. [ABSTRACT FROM AUTHOR]

This study focuses on the performance of the elastic–viscous–plastic (EVP) dynamical solver within the sea ice model, CICE v6.5.1. The study has been conducted in two steps. First, the standard EVP solver was extracted from CICE for experiments with refactored versions, which are used for performance testing. Second, one refactored version was integrated and tested in the full CICE model to demonstrate that the new algorithms do not significantly impact the physical results. The study reveals two dominant bottlenecks, namely (1) the number of Message Parsing Interface (MPI) and Open Multi-Processing (OpenMP) synchronization points required for halo exchanges during each time step combined with the irregular domain of active sea ice points and (2) the lack of single-instruction, multiple-data (SIMD) code generation. The standard EVP solver has been refactored based on two generic patterns. The first pattern exposes how general finite differences on masked multi-dimensional arrays can be expressed in order to produce significantly better code generation by changing the memory access pattern from random access to direct access. The second pattern takes an alternative approach to handle static grid properties. The measured single-core performance improvement is more than a factor of 5 compared to the standard implementation. The refactored implementation of strong scales on the Intel® Xeon® Scalable Processors series node until the available bandwidth of the node is used. For the Intel® Xeon® CPU Max series, there is sufficient bandwidth to allow the strong scaling to continue for all the cores on the node, resulting in a single-node improvement factor of 35 over the standard implementation. This study also demonstrates improved performance on GPU processors. [ABSTRACT FROM AUTHOR]

This study aims to evaluate and compare the predictive accuracy of Sonazoid-contrast-enhanced ultrasound (CEUS) and Gd-EOB-DTPA-enhanced MRI for detecting microvascular invasion (MVI) in hepatocellular carcinoma (HCC). In this single-center prospective study, we included 64 patients with histopathologically confirmed single HCC lesions. Based on post-operative pathologic data, patients were categorized into two groups: those with MVI (n = 21) and those without MVI (n = 43). The diagnostic efficacy of CEUS was compared with that of MRI in predicting MVI. Multifactorial analysis revealed that US features (tumor size > 4.35 cm, peritumoral enhancement, post-vascular ring enhancement, peak energy in the arterial phase of the difference between the margin area of HCC and distal liver parenchyma <−1.0 × 106 a.u), MRI features (rim enhancement, irregular tumor margin, and the halo sign) were all independent predictors of MVI (p < 0.05). The sensitivity and specificity of CEUS features in predicting MVI ranged from 61.9% to 86.4% and from 42.9% to 71.4%, respectively. For MRI features, the sensitivity and specificity ranged from 33.3% to 76.3% and from 54.7% to 90.5%, respectively. No statistically significant differences were observed in the area under the curve between CEUS and MRI (p > 0.05). Notably, peak energy of the difference showed the highest sensitivity at 86.4%, while the halo sign in MRI exhibited the highest specificity at 90.5%. Sonazoid-CEUS and Gd-EOB-DTPA-enhanced MRI demonstrate potential in predicting MVI in HCC lesions. Notably, CEUS showed higher sensitivity, whereas MRI displayed greater specificity in predicting MVI. [ABSTRACT FROM AUTHOR]

Anti-icing technologies are vital across various sectors, from transportation to energy systems. In this study, we investigate the formation of condensation halos during the process of condensation–freezing on superhydrophobic surfaces. Experimental tests were conducted on metallic nanostructured superhydrophobic surfaces, where droplet icing was induced and observed under controlled conditions. The formation of condensation halos, characterized by the sudden appearance and subsequent vanishing of microdroplets around the freezing droplets, was captured and analyzed. A vapor diffusive model coupled with heterogeneous nucleation theory was developed to understand and quantify the growth of condensation halos. The model considers vapor diffusion around the icing droplet and the critical vapor pressure required for nucleation. Experimental observations and theoretical predictions demonstrated a strong dependence of condensation halo size on the icing droplet radius. The study sheds light on the mechanisms underlying condensation halo formation and provides insights into the intricate interplay between droplet size, surface properties, and environmental conditions in condensation–freezing phenomena, offering valuable perspectives for the development of effective anti-icing strategies. [ABSTRACT FROM AUTHOR]

The HALO–(AC)3 aircraft campaign was carried out in March and April 2022 over the Norwegian and Greenland Seas, the Fram Strait, and the central Arctic Ocean. Three research aircraft, the High Altitude and Long Range Research Aircraft (HALO), Polar 5, and Polar 6, performed 54 partly coordinated research flights on 23 flight days over areas of open ocean, the marginal sea ice zone (MIZ), and the central Arctic sea ice. The general objective of the research flights was to quantify the evolution of air mass properties during moist and warm air intrusions (WAIs) and cold air outbreaks (CAOs). To gain a comprehensive data set, the three aircraft followed different strategies. HALO was equipped with active and passive remote sensing instruments and dropsondes to cover the regional evolution of cloud and thermodynamic processes. Polar 5 carried a similar remote sensing payload as HALO, and Polar 6 was instrumented with in-situ cloud, aerosol, and trace gas instruments focusing on the initial air mass transformation close to the MIZ. The processed, calibrated, and validated data are published in the World Data Center PANGAEA as instrument-separated data subsets and listed in aircraft-separated collections for HALO (Ehrlich et al., 2024a), Polar 5 (Mech et al., 2024a), and Polar 6 (Herber et al., 2024). A detailed overview of the available data sets is provided here. Furthermore, the campaign-specific instrument setup, the data processing, and data quality are summarized. Based on measurements conducted during a specific CAO, it is shown that the scientific analysis of the HALO– (AC)3 data benefits from the coordinated operation of the three aircraft. [ABSTRACT FROM AUTHOR]

Context. White dwarfs are considered to be efficient cosmochronometers. Thanks to the recent space-borne mission Gaia, a nearly complete sample up to about 100 parsecs from the Sun has been compiled. However, the Galaxy, as a dynamic system, implies that these objects may have very diverse origins. It is therefore of paramount importance to characterize the origins of white dwarfs from the different Galactic structure components found in our solar neighborhood. Aims. We aim to compute the Galactic orbits for white dwarfs of the thin and thick disk, as well as the halo components observed in our solar neighborhood. On the basis of these determinations, we analyze the most probable regions of the Galaxy where they could have formed, along with the distribution of their orbital parameters and the observational biases introduced when constructing the local sample. Methods. We used a detailed Galactic orbit integration package, in conjunction with a detailed population synthesis code specifically designed to replicate the different Galactic components of the white dwarf population. Synthetic stars were generated based on the current observational sample and their orbital integration allowed for the reconstruction of the population's history. Results. Our kinematic analysis of the white dwarf population reveals the ephemeral nature of the concept of the solar neighborhood, as the majority of thin-disk, thick-disk, and halo white dwarfs will have left our 100 pc neighborhood in approximately 3.30 Myr, 1.05 Myr, and 0.6 Myr, respectively. Moreover, the spatial distribution of the integrated thin-disk orbits suggests that 68% of these stars were formed at less than 1 kpc from the Sun, while most of the thick-disk members have undergone radial disk migration. Halo members are those stars that typically belong to the "inner halo", given that their orbits mostly planar and do not extend beyond R = 20 − 25 kpc. Despite the observational bias, which mostly affects the oldest stars in the thick disk and halo, we show that the wider distribution of orbital parameters is well represented by the sample. Conclusions. The solar neighborhood is a transitory concept, whereby its current population of white dwarfs originates from larger regions of the Galaxy. This fact must be taken into account when analyzing the overall properties of such a population, such as its age distribution, metallicities, and formation history. Even so, the kinematic properties observed by recent missions such as Gaia are representative of the total population up to a distance of approximately 500 pc. [ABSTRACT FROM AUTHOR]

Me 2-1 is a high-excitation planetary nebula whose morphology and physical structure have not yet been investigated. We present narrow-band images in several emission lines, and high- and intermediate-resolution long-slit spectra aimed at investigating its morphology and 3D structure, and its physical parameters and chemical abundances. By applying deconvolution techniques to the images, we identified in Me 2-1: an elliptical ring; two elongated, curved structures (caps) that contain three pairs of bright point-symmetric (PS) knots; a shell interior of the ring; and a faint halo or attached shell. The caps are observed in all images, while the PS knots are only observed in the low-excitation emission line ones. These structures are also identified in the high-resolution long-slit spectra, allowing us to study their morphokinematics. The 3D reconstruction shows that Me 2-1 consists of a ring seen almost pole-on, and a virtually spherical shell, to which the caps and PS knots are attached. Caps and PS knots most probably trace the sites where high-velocity collimated bipolar outflows, ejected along a wobbling axis, collide with the spherical shell, are slowed down, and remain attached to it. Although the main excitation mechanism in Me 2-1 is found to be photoionization, a contribution of shocks in the PS knots is suggested by their emission line ratios. The combination of collimated outflows and a ring with a spherical shell is unusual among planetary nebulae. We speculate that two planets, each with less than one Jupiter mass, could be involved in the formation of Me 2-1 if both enter a common envelope evolution during the asymptotic giant branch phase of the progenitor. One planet is tidally disrupted, forming an accretion disk around the central star, from which collimated bipolar outflows are ejected; the other planet survives, causing wobbling of the accretion disk. The physical parameters and chemical abundances obtained from our intermediate-resolution spectrum are similar to those obtained in previous analyses, with the abundances also pointing to a low-mass progenitor of Me 2-1. [ABSTRACT FROM AUTHOR]

The rotation of the Milky Way halo in the solar vicinity is studied using kinematic data of the GAIA DR3 catalog for RR Lyrae variable stars with parallax errors of less than 20%. Two criteria were used for selecting halo stars: kinematic and spatial. In both approaches, we confirm the existence of weak rotation of the halo in the direction opposite to the rotation of the Galactic disk with velocities of km/s for the kinematic criterion and km/s for the spatial criterion. [ABSTRACT FROM AUTHOR]

ADITYA-L1 is India's first dedicated mission to observe the Sun and its atmosphere from a halo orbit around L1 point. Visible emission line coronagraph (VELC) is the primary payload on board Aditya-L1 to observe the Sun's corona. VELC is designed as an internally occulted reflective coronagraph to meet the observational requirements of wide wavelength band and the field of view close to the solar limb (1.05 R Sun ). Images of the solar corona in continuum and spectra in three emission lines 5303 Å [Fe xiv], 7892 Å [Fe xi] and 10747 Å [Fe xiii] obtained with high cadence are to be analyzed using software algorithms automatically. A reasonable part of these observations will be made in a synoptic mode in which the data are processed through a standard pipeline and the resulting products will be made available for public use. The procedure involves the calibration of instrument and detectors, converting the images into the FITS format, correcting the images and spectra for the instrumental effects, and aligning the images (in terms of position angles and image scales) etc. Then, develop image processing algorithms to detect the occurrence of energetic events using continuum images. Also derive physical parameters, such as temperature and velocity structure of solar corona using emission line observations. Here, we describe the calibration of detectors and the development of software algorithms to detect the occurrence of CMEs and analyze the spectroscopic data. [ABSTRACT FROM AUTHOR]

Microrheology, the study of material flow at micron scales, has advanced significantly since Robert Brown's discovery of Brownian motion in 1827. Mason and Weitz's seminal work in 1995 established the foundation for microrheology techniques, enabling the measurement of viscoelastic properties of complex fluids using light-scattering particles. However, existing techniques face limitations in exploring very slow dynamics, crucial for understanding biological systems. Here, we present a proof of concept for a novel microrheology technique called "Optical Halo", which utilises a ring-shaped Bessel beam created by optical tweezers to overcome existing limitations. Through numerical simulations and theoretical analysis, we demonstrate the efficacy of the Optical Halo in probing viscoelastic properties across a wide frequency range, including low-frequency regimes inaccessible to conventional methods. This innovative approach holds promise for elucidating the mechanical behaviour of complex biological fluids. [ABSTRACT FROM AUTHOR]

If z > 6 quasars reside in rare, massive haloes, ΛCDM cosmology predicts they should be surrounded by an anomalously high number of bright companion galaxies. Here, I show that these companion galaxies should also move unusually fast. Using a new suite of cosmological, 'zoom-in' hydrodynamic simulations, I present predictions for the velocity distribution of quasar companion galaxies and its variation with quasar host halo mass at |$z \, = \, 6$|⁠. Satellites accelerate as they approach the quasar host galaxy, producing a line-of-sight velocity profile that broadens with decreasing distance to the quasar host galaxy. This increase in velocity dispersion is particularly pronounced if the host halo mass is |$\gtrsim 5 \times 10^{12} \, \rm M_\odot$|⁠. Typical line-of-sight speeds rise to |$\approx 500 \, \rm km \, s^{-1}$| at projected radii |$\sim 10 \, \rm kpc$|⁠. For about 10 per cent of satellites, they should exceed |$800 \, \rm km \, s^{-1}$|⁠ , with |$\approx 5~{{\ \rm per\ cent}}$| of companions reaching line-of-sight speeds |$\sim 1000 \, \rm km \, s^{-1}$|⁠. For lower host halo masses |$\approx 5 \times 10^{11}{-}10^{12} \, \rm M_\odot$|⁠ , the velocity profile of companion galaxies is significantly flatter. In this case, typical line-of-sight velocities are |$\approx 250 \, \rm km \, s^{-1}$| and do not exceed |$\approx 500 \, \rm km \, s^{-1}$|⁠. A comparison with existing Atacama Large Millimeter/submillimeter Array (ALMA), JWST and Multi-Unit Spectroscopic Explorer (MUSE) line-of-sight velocity measurements reveals that observed z > 6 quasar companions closely follow the velocity distribution expected for a host halo with mass |$\gtrsim 5 \times 10^{12} \, \rm M_\odot$|⁠ , ruling out a light host halo. Finally, through an estimate of ultraviolet and [ |$\rm O \, {\small III}$| ] luminosity functions, I show that the velocity distribution more reliably discriminates between halo mass than companion number counts, which are strongly affected by cosmic variance. [ABSTRACT FROM AUTHOR]

Many types of halos (including arcs) appear in the sky. Each type of halo corresponds to the shape and orientation of ice crystals in clouds, and reflects the state of the atmosphere; therefore observing them from the ground greatly helps in understanding the state of the atmosphere. However, halos are easily obscured by the contrast of the cloud itself, making it difficult to observe them. This difficulty can be overcome by enhancing halos in images, for which various techniques have been developed. This study describes the construction of a sky-color model for halos and a new effective algorithm to reveal halos in images. [ABSTRACT FROM AUTHOR]

We research measurement conditions that allow omitting stray light blocking masks in camera‐based halo measurements of FALD LCDs. The stray light induced error is reduced by using high magnifications and stray light optimized hardware and test patterns. Our findings simplify halo measurements and enable simultaneous peak luminance and uniformity measurements. [ABSTRACT FROM AUTHOR]

Image dehazing is one of the pivotal topics in computer vision arena due to its significant effects on improving the foggy images that taken under poor weather conditions. Problems such as halo outliers and over-saturation are presented in the ridges i.e. high-frequency components of the hazy images which lead to false guesstimate of atmospheric light and transmission depth that negatively results on the task of visibility restoration image. In this paper, the proposed method has the ability to deal with hazy images with several haze density while most of state-of-the-art dehazing techniques suffer from lack of contrast of the observed object in the dehazed images due to unequal distribution of transmission depth. In order to achieve high visual quality from the contaminated hazy images, the proposed method is designed according to semi soft thresholding and Gamma transformation where the second-generation wavelet transformation is used to improve the transmission map. Qualitative and quantitative results showed that, the proposed method outperforms sophisticated state-of-the-art image haze removal techniques both in visual image quality and time efficiency. [ABSTRACT FROM AUTHOR]

According to the characteristics of the halo phenomenon of Mini‐LED partition backlit LCD display, we measure the luminance and distribution of the halo by using the measurement method established before, and further analyze the influencing factors. Based on the hardware characteristics of this type of display, we extract three factors that affect the intensity of the halo, which are the luminance of the display area, the native contrast of the display panel and the number or size of the backlight partition. We designed and carried out the halo visual perception evaluation experiment according to the influencing factors of the halo, and further established the halo sensitivity model, which took the width and luminance of the halo as independent variables, and the predicted value of the halo was highly correlated with the evaluation value (R 2 >0.90). Finally, we analyzed the influence trend of various factors on the intensity of the halo through the established model, and proposed a hardware‐based halo improvement scheme. At the same time, the model also helped to establish the evaluation standard of the halo. [ABSTRACT FROM AUTHOR]

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This article discusses the presence of a halo phenomenon surrounding café au lait macules (CALMs) within Mongolian spots in children with neurofibromatosis type 1 (NF1). The authors share their experience of seeing four cases in which NF1 was subsequently confirmed by genetic testing, and CALMs were surrounded by a hypopigmented halo. They suggest that this phenomenon could be considered an additional cutaneous criterion to suspect the diagnosis of NF1 in uncertain cases. The article also mentions previous case reports on this topic and the uncertain pathogenesis of the halo phenomenon. [Extracted from the article]

The neutron-rich nucleus 11Be is one of the most enigmatic exotic nuclei in the periodic table. It exhibits a multitude of unique and intriguing phenomena within a single nucleus, including the halo phenomenon, clustering structure, and parity inversion. A unified description of these exotic properties represents a significant challenge for the nuclear physics field. By employing the axially deformed relativistic Hartree-Fock-Bogoliubov (D-RHFB) model, we have successfully reproduced the parity inversion and the one-neutron halo in 11Be, and revealed the underlying cluster structure. It is found that the intrusion of the sd -shell, which results in the parity inversion, is coherently connected with the halo and cluster structures. In particular, the s -wave is responsible for the halo formation, and the mixing of 2 s 1 / 2 - and 1 d 5 / 2 -waves enhances the cluster structure. This work elucidates the coherence between the parity inversion and the halo/cluster structures of 11Be, and addresses the long-standing challenge of providing a unified explanation for the multiple exotic phenomena observed in 11Be. [ABSTRACT FROM AUTHOR]

The Bytíz deposit is a part of the Příbram uranium and base-metal ore district. It is an example of a vein-type deposit with polyphase hydrothermal mineralization. Samples of uraniferous solid bitumen from Bytíz with U content up to 38 wt% are characterized petrologically, geochemically, and mineralogically using EPMA, Raman and infrared microspectroscopy. The bitumen-bearing samples consist of base-metal sulfides: galena, sphalerite, pyrite, chalcopyrite, and also minor amounts of tetrahedrite, stibnite, and acanthite, associated with Mn-bearing calcite, quartz and silicates (chlorite, muscovite). Solid bitumens were found in the form of small veins and droplets, and roundish to irregular accumulations, in association with uraninite and carbonate veins. U-bearing minerals in the studied samples are represented by uraninite and more rarely by coffinite. Three generations of uraninite in association with solid bitumen were distinguished: 1. spherulites and large grains, filled with organic phase in the cracks; 2. as a part of complex textures inside areas with organic matter; in this case, the uraninite was assumed to have been remobilized; and 3. small inclusions in the latest calcite veins. More than 80 vol% of the solid bitumen from the vein fillings appeared to be radiolytically altered. Radiolytic alteration results in changes in optical properties and in composition, and in the formation of various textures around uraninite grains: halos, and irregular textures from simple massive to flow, dendritic, and fractured to a very complex morphology. The random reflectance values of unaltered mineral-free bitumen range from 0.45% to 0.99%, while in the radiolytically altered bitumen the average reflectance values are higher, from approximately 1.72% to 3.44%. The degree of graphitization of the organic matter was assessed by infrared micro-spectroscopy. Spectral maps show significant destruction changes of the aliphatic C H bonds and an increase in the content of oxygen functional groups in the vicinity of U minerals. On the element distribution maps, obtained by EPMA, the distribution of S, U, Pb and other elements across solid bitumen in the vicinity of uraninite and coffinite has a very heterogeneous character. An elevated content of sulfur in bitumen was also found, as well as a clear interdependence between S and C. It is suggested that the presence of sulfur in solid bitumen may result in 'clouding' of the solid bitumen with tiny stibnite grains. The dark rims of the halos observed under the optical microscope may be due to an elevated U content at the rims around the uraninite. Based on analysis of complex textural relationships of the solid bitumens with coexisting minerals, the formation of solid bitumen in association with uraninite is therefore assumed to relate to several stages of the influx of hydrothermal fluid. The temperature of the fluid, associated with bitumen formation was estimated to be up to 270 °C, according to chlorite thermometry. [ABSTRACT FROM AUTHOR]

• Based on temperature field simulation and validation, as well as taper contour simulation and validation, this study proposed a method that effectively simulated the light transmission trajectories of a single fiber in tapered optical fibers. • The findings in this article provided insight into how the behavior of individual tapered fibers in a tapered optical fiber array affected imaging quality, and consequently provided theoretical design for eliminating halo defects and improving the uniformity of light transmission. • The transmittance and uniformity of TOFA were tested using self-developed transmittance detection equipment, providing a method for verifying simulation results. Tens of millions or billions of single tapered fibers are independent optical transmission elements of tapered optical fiber array (TOFA) for imaging. The optical transmission trajectories of these single tapered fibers, which directly affect imaging qualities of TOFA, are rarely analyzed. This paper provides a method to numerically simulate it for fibers located at different positions along the radial direction of TOFA. The tapered curves of TOFA were firstly simulated by Finite Element Analysis (FEA) software and experimentally verified by the same preparation parameters. It is shown that the slope of tapered curve increases with stretching length. Meanwhile, the taper angle gets greater, and the profile of tapered deformation zone expands outward, while the radius of straight zone remains stable. Based on these, the optical transmission trajectory of single tapered fibers located from center to edge in TOFA was simulated, and then further verified by a self-developed instrument. Both simulation and experiment illustrate that the relative transmittance of single tapered optical fiber is decreased along the radial direction within the same TOFA. In comparison with the transmittance of the central axial fiber, the simulated and experimental unevenness on relative transmittance of peripheral fibers is within 7.11% and 9.74%, respectively. With the relative transmittance at the central position of the optical fiber being identical, the difference of relative transmittance (Δ T) between the simulation and experiment is gradually increased from center to peripheral regions along the radial direction of TOFA, reaching the maximum Δ T of 4.23%. The simulated results are well in agreement with the experimental ones. [ABSTRACT FROM AUTHOR]

This article, titled "GIS Tips Tricks: When Labels and Text Matter," provides tips and tricks for improving the lettering and labeling on maps using ArcGIS Pro. The author emphasizes the importance of not accepting default settings and suggests using different fonts, colors, and halos to enhance the legibility and aesthetics of map labels. The article also mentions the option to adjust letter spacing and provides resources for further learning. The author advises against using the Comic Sans font, unless the map is intended for children. [Extracted from the article]

The article focuses on the outcomes of several meteorological competitions and events. The Meteovídeo'2024 contest concluded with "IberianX" by Benjamín Porée securing the top spot, while the Meteoinvierno'2024 photography competition crowned "Reino lenticular" by Imanol Zuaznabar as the winning entry. It highlights the completion of a decade-long cycle of seasonal competitions, marked by the commemorative poster displaying all past winners.

• A front side fast and wide Coronal Mass Ejection (CME) event propagated on February 17, 2023, is analysed. • The solar X-ray flare emission associated with this event is very intensive (X2.3). • The Type II radio emission generated in the wavelength range of 25 MHz – 180 kHz represents a Mkm Type II radio burst. • The kind of IP shock observed in the current study is a fast and forward type event. • ICME is a pure magnetic cloud type event. In the present work, propagation of an earth directed fast and wide Coronal Mass Ejection event on 17 February 2023 is studied in detail. The complex magnetic configuration in the Active Region (AR) 13229 at N25E64 caused an intensive X2.3 flare with a peak at 19:38 UT. It is followed by a massive halo CME event observed in the LASCO C3 coronagraph with a linear speed of 930 km/s and shock speed of 1300 km/s. A low frequency Type II emission was detected in the frequency range 10 MHz – 180 kHz during 20:30 UT-04:45 UT on 18 Feb 2023 by space borne Wind/WAVES instrument. From the OMNI data, the IP shock and the ICME reached earth's magnetosphere on 20 Feb 2023. A fast forward type shock was observed using OMNI high resolution data. The IP shock and ICME affected the Galactic Cosmic ray (GCR) detection. This event caused large magnetic turbulences in sheath region caused a major geomagnetic storm (∼-100 nT). [ABSTRACT FROM AUTHOR]

Based on the point-coupling density functional, the time-odd deformed relativistic Hartree-Bogoliubov theory in continuum (TODRHBc) is developed. The effects of nuclear magnetism on halo phenomenon are explored by taking the experimentally suggested deformed halo nucleus 31Ne as an example. For 31Ne, nuclear magnetism contributes 0.09 MeV to total binding energy, and the breaking of Kramers degeneracy results in a 0 – 0.2 MeV splitting in the canonical single particle spectra. The blocked neutron level has a dominant component of the p wave and is marginally bound. However, if we ignore nuclear magnetism, the level becomes unbound. This shows a subtle mechanism that nuclear magnetism changes the single particle energies, causing a nucleus to become bound. Based on the TODRHBc results, a prolate one-neutron halo is formed around the near-spherical core in 31Ne. The nucleon current is mostly contributed by the halo rather than the core, except near the center of the nucleus. A layered feature in the neutron current distribution is observed and studied in detail. [ABSTRACT FROM AUTHOR]

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The document titled "Solar halos" features several images of solar halos observed in different locations and dates. The images showcase various types of solar halos, including 22° solar halos, parhelia, parhelic circles, upper tangent arcs, and lower tangent arcs. The solar halos are formed by the interaction of sunlight with ice crystals in the atmosphere. The document provides a visual representation of these atmospheric phenomena and can be useful for researchers studying weather patterns and atmospheric optics. [Extracted from the article]

The volcanic eruption of La Palma in September 2021 was explosive and effusive, emitting ash, pyroclasts, and gases. Cumulus and stratocumulus clouds were formed due to the emissions of particles and water vapor, as well as pyrocumulus clouds at an altitude of approximately 6 km. The eruption officially concluded on December 25, 2021. During the eruption, meteorological phenomena such as clouds with more smaller droplets, gravity waves in the atmosphere due to the interaction between the eruptive column and Saharan air, volcanic lightning, green flashes, and halos around the sun were observed. [Extracted from the article]