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It is very well known that the fraction of energy in a hadron collision going into electromagnetic particles (electrons and photons, including those from decays) has a large impact on the number of muons produced in air shower cascades. Recent measurements at the LHC confirm features that can be linked to a mixture of different underlying particle production mechanisms such as a collective statistical hadronization (core) in addition to the expected string fragmentation (corona). Since the two mechanisms have a different electromagnetic energy fraction, we present a possible connection between statistical hadronization in hadron collisions and muon production in air showers. Using a novel approach, we demonstrate that the core-corona effect as observed at the LHC could be part of the solution for the lack of muon production in simulations of high energy cosmic rays. To probe this hypothesis, we study hadronization in high energy hadron collisions using calorimetric information over a large range of pseudorapidity in combination with the multiplicity of central tracks. As an experimental observable, we propose the production of energy in electromagnetic particles versus hadrons, as a function of pseudorapidity and central charged particle multiplicity.

We carried out a new attempt to check for the presence promethium lines in the spectrum of HD101065 (Przybylski's star). The neutron capture element promethium does not have stable isotopes and the maximum half-life time is about 18 years. Thus its presence in this peculiar star would indicate an ongoing process of irradiation of its surface layers with free neutrons. Unfortunately, almost all promethium lines are heavily blended with lines of other neutron capture elements and other species. We selected and analysed three lines of promethium (Pm I and Pm II) and came to the conclusion that at present it is impossible to definitely claim the presence of this element in Przybylski's star atmosphere., Accepted for publication in Astronomische Nachrichten

We report initial results from an ongoing spectroscopic survey of central stars of faint planetary nebulae (PNe), obtained with the Low-Resolution Spectrograph on the Hobby-Eberly Telescope. The six PN nuclei (PNNi) discussed here all have strong emission at the O VI 3811-3834 A doublet, indicative of very high temperatures. Five of them--the nuclei of Ou 2, Kn 61, Kn 15, Abell 72, and Kn 130--belong to the hydrogen-deficient PG 1159 class, showing a strong absorption feature of He II and C IV at 4650-4690 A. Based on exploratory comparisons with synthetic model-atmosphere spectra, and the presence of Ne VIII emission lines, we estimate them to have effective temperatures of order 170,000 K. The central star of Kn 15 has a Wolf-Rayet-like spectrum, with strong and broad emission lines of He II, C IV, N V, and O V-VI. We classify it [WO2], but we note that the N V 4604-4620 A emission doublet is extremely strong, indicating a relatively high nitrogen abundance. Several of the emission lines in Kn 15 vary in equivalent width by factors as large as 1.5 among our four observations from 2019 to 2022, implying significant variations in the stellar mass-loss rate. We encourage spectroscopic monitoring. Follow-up high-time-resolution photometry of these stars would be of interest, given the large fraction of pulsating variables seen among PG 1159 and [WO] PNNi., Comment: Accepted by MNRAS

Geometry and dynamical structure of emission regions in accreting pulsars are shaped by the interplay between gravity, radiation, and strong magnetic field, which significantly affects the opacities of a plasma and radiative pressure under such extreme conditions. Quantitative consideration of magnetic plasma opacities is, therefore, an essential ingredient of any self-consistent modeling of emission region structure of X-ray pulsars. We present results of computations of the Rosseland and Planck mean opacities of a strongly magnetized plasma with a simple chemical composition,namely the solar hydrogen/helium mix. We consider all relevant specific opacities of the magnetized plasma including vacuum polarization effect and contribution of electron-positron pairs where the pair number density is computed in the thermodynamic equilibrium approximation. The magnetic Planck mean opacity determines the radiative cooling of an optically thin strongly magnetized plasma. It is by factor of three smaller than non-magnetic Planck opacity at $k_{\rm B}T < 0.1\,E_{\rm cyc}$ and increases by a factor of $10^2 - 10^4$ at $k_{\rm B}T > 0.3\,E_{\rm cyc}$ due to cyclotron thermal processes. We propose a simple approximate expression which has sufficient accuracy for the magnetic Planck opacity description. We provide the Rosseland opacity in a tabular form computed in the temperature range 1 - 300 keV, magnetic field range $3 \times 10^{10} - 10^{15}$ G, and a broad range of plasma densities. We demonstrate that the scattering on the electron-positron pairs increases the Rosseland opacity drastically at temperatures >50 keV in the case of mass densities typical for accretion channel in X-ray pulsars., 14 pages, 12 figures, accepted for publication in MNRAS, added with data files and an interpolation code together with their description

Diuretics are drugs that increase the volume of urinary excretion. Generally, they inhibit renal transport of ions and reduce sodium reabsorption in different portions of the nephron, consequently the eliminated ions are concentrated in greater amounts together with water. Therefore, these substances increase urine output, often alter its pH, as well as the ionic arrangement of urine and blood. The following objective was to describe, through a narrative review of the literature, the main aspects of each class of diuretics and the specific clinical conditions for their administration. The applicability of the different classes is according to the increase in sodium secretion. Loop diuretics are considered the most potent, followed by thiazides. The other classes are used either in combination to promote additional diuresis, to preserve a given condition, or to be better suited to a specific comorbidity. Diuretics are indicated in conditions that require normalization of abnormal fluid retention, edema, or management of hypertension. Los diuréticos son fármacos que aumentan el volumen de excreción urinaria. Generalmente inhiben el transporte renal de iones y reducen la reabsorción de sodio en diferentes porciones de la nefrona, por lo que los iones eliminados se concentran en mayor cantidad junto con el agua. Por lo tanto, estas sustancias aumentan la producción de orina, a menudo alteran su pH, así como la disposición iónica de la orina y la sangre. El siguiente objetivo fue describir, a través de una revisión narrativa de la literatura, los principales aspectos de cada clase de diuréticos y las condiciones clínicas específicas para su administración. La aplicabilidad de las diferentes clases es de acuerdo al incremento en la secreción de sodio. Los diuréticos de asa se consideran los más potentes, seguidos de las tiazidas. Las otras clases se usan en combinación para promover diuresis adicional, para preservar una condición dada o para adaptarse mejor a una comorbilidad específica. Los diuréticos están indicados en condiciones que requieren la normalización de la retención anormal de líquidos, edema o manejo de la hipertensión. Diuréticos são fármacos que elevam o volume de excreção urinária. Geralmente, inibem o transporte renal de íons e reduzem a reabsorção de sódio em distintas porções do néfron, consequentemente os íons eliminados se concentram em maiores quantidades junto de água. Logo, estas substâncias aumentam débito urinário, frequentemente alteram seu pH, bem como o arranjo iônico da urina e do sangue. O seguinte objetivou descrever através da revisão narrativa de literatura, os principais aspectos de cada classe de diuréticos e as condições clínicas específicas para administração destes. A aplicabilidade das diversas classes é de acordo com o aumento da secreção de sódio. O diurético de alça é considerado o mais potente, seguido dos tiazídicos. As demais classes são usados ou em combinação para promover diurese adicional, preservar determinada condição ou por serem mais adequadas a uma comorbidade específica. Os diuréticos são indicados em ocorrências que exijam normalizar a retenção anômala de líquido, o edema ou o manejo da hipertensão.

Die Transplantation mesenchymaler pluripotenter Zellen zur Regeneration von Knorpelschaden wurde aufgrund gesetzlicher Reglementierungen bisher hauptsachlich in ausereuropaischen Landern durchgefuhrt. Adipogene Stammzellen konnen in der stromal-vaskularen Fraktion (SVF) gefunden werden und haben vergleichbare immunmodulatorische und antiinflammatorische Eigenschaften zu Stammzellen, welche im Knochenmark vorkommen. Der unkomplizierte Zugang und die geringe Entnahmemorbiditat machen die Therapie mit SVF zur einer besonders interessanten Therapieoption fur die Behandlung der Arthrose. Die Studie untersucht, ob die Infiltration des Hoffa-Fettkorpers mit SVF bei Patienten mit Gonarthrose eine effektive und sichere Therapieoption darstellt. Des Weiteren werden die Anzahl und Vitalitat der injizierten Zellen sowie die klinische Wirksamkeit evaluiert. Es handelt sich um eine prospektive Fallserie, in der13 Patienten im Alter von 55–88 Jahren mit einem Kellgren-Lawrence-Score bis 3 eine Infiltration mit SVF in den Hoffa’schen Fettkorper erhalten. Die Anzahl und Vitalitat der Zellen werden mit einem Zellzahler gemessen. Das klinische Ergebnis wird mit der visuellen Analogskala (VAS) fur Schmerzempfindung und dem Knee Injury and Osteoarthritis Outcome Score (KOOS) mit einer geplanten Follow-up-Periode von 2 Jahren uberpruft. Auswertbare, vollstandige Verlaufe uber 6 Monate liegen bei 13 Patienten vor. Es wurden 3,21 E + 07 ± 2,45 E + 07 Zellen injiziert. Der durchschnittliche Anteil an vitalen Zellen betrug 78 ± 9 %. Nach 6 Monaten konnte eine signifikante Verbesserung der VAS und der jeweiligen Subskalen des KOOS im Vergleich zum Basiswert beobachtet werden. Es traten keine Komplikationen oder Nebenwirkungen auf. Diese ersten Ergebnisse zeigen, dass die Behandlung mit SVF eine sichere Therapieoption darstellt, welche das Potenzial hat, die durch Kniegelenksarthrose entstehenden/entstandenen Schmerzen zu lindern und die Funktion signifikant zur verbessern. Die Zellzahl und Vitalitat der Zellen liegen im erwarteten und bisher publizierten Bereich.

Central compact objects (CCOs) are neutron stars found close to the center of some supernova remnants. A certain number of them are presumably covered by carbon envelopes. Their unpulsed thermal X-ray emission can originate either from the entire surface covered by a carbon atmosphere or alternatively from a nonuniformly emitting hydrogen atmosphere. However, the latter scenario appears unlikely given the available upper limits on the amplitude of pulsations. Here we explore a possibility to further discriminate between the two scenarios using X-ray polarimetric observations. We compute the polarization degree (PD) for nonmagnetized pure-carbon and pure-hydrogen atmospheres with effective temperatures of between 1 and 6 MK and find that it can reach up to 25% and 40% for hydrogen and carbon atmospheres, respectively, in the photon energy band 1-10 keV. However, given the available constraints on possible inhomogeneities of the temperature distribution deduced from models of the X-ray spectrum of the CCO in HESS J1731-347, the integrated PD appears to be very low for both carbon (, 10 pages, 16 figures. accepted to be published by A&A, corrected after the language Editor remarks, misprints in some numbers were corrected, a new version of Fig.15

Novae are caused by runaway thermonuclear burning in the hydrogen-rich envelopes of accreting white dwarfs, which results in the envelope to expand rapidly and to eject most of its mass. For more than 30 years, nova theory has predicted the existence of a "fireball" phase following directly the runaway fusion, which should be observable as a short, bright, and soft X-ray flash before the nova becomes visible in the optical. Here we present the unequivocal detection of an extremely bright and very soft X-ray flash of the classical Galactic nova YZ Reticuli 11 hours prior to its 9 mag optical brightening. No X-ray source was detected 4 hours before and after the event, constraining the duration of the flash to shorter than 8 hours. In agreement with theoretical predictions, the source's spectral shape is consistent with a black body of $3.27^{+0.11}_{-0.33}\times 10^5$ K ($28.2^{+0.9}_{-2.8}$ eV), or a white dwarf atmosphere, radiating at the Eddington luminosity, with a photosphere that is only slightly larger than a typical white dwarf. This detection of the expanding white dwarf photosphere before the ejection of the envelope provides the last link of the predicted photospheric lightcurve evolution and opens a new window to measure the total nova energetics., Comment: Published in Nature on 11 May 2022

We present two new GW Vir-type pulsating white dwarf stars, TIC\,0403800675 (WD\,J115727.68-280349.64) and TIC\,1989122424 (WD J211738.38-552801.18) discovered in the Transiting Exoplanet Survey Satellite (TESS) photometric data. For both stars, the TESS light curves reveal the presence of oscillations with periods in a narrow range between 400 and 410\,s, which are associated with typical gravity ($g$)-modes. Follow-up ground-based spectroscopy shows that both stars have similar effective temperature ($T_\mathrm{eff} = 110,000 \pm 10,000$\,K) and surface gravity ($\log g = 7.5 \pm 0.5$), but different He/C composition (mass fractions): He\,=\,0.75 and C\,=\,0.25 for TIC\,0403800675, and He\,=\,0.50 and C\,=\,0.50 for TIC\,1989122424. By performing a fit to their spectral energy distributions, we found for both stars radii and luminosities of $R=0.019\pm0.002\,R_\odot$ and $\log(L/L_\odot)=1.68^{+0.15}_{-0.24}$, respectively. By employing evolutionary tracks of PG~1159 stars, we find the masses of both stars to be $0.56\pm0.18 M_{\odot}$ from the $\log g$-$T_\mathrm{eff}$ diagram and $0.60^{+0.11}_{-0.09} M_{\odot}$ from the Hertzsprung Russell diagram., 8 Pages. arXiv admin note: text overlap with arXiv:2108.11093