XMM-Newton view of Swift J1834.9-0846 and its Magnetar Wind Nebula

We report on the analysis of two XMM-Newton observations of the recently discovered soft gamma repeater Swift J1834.9-0846, taken in September 2005 and one month after the source went into outburst on 2011 August 7. We performed timing and spectral analyses on the point source as well as on the extended emission. We find that the source period is consistent with an extrapolation of the Chandra ephemeris reported earlier and the spectral properties remained constant. The source luminosity decreased to a level of 1.6x10^34 erg s^-1 following a decay trend of $\propto t^{-0.5}$. Our spatial analysis of the source environment revealed the presence of two extended emission regions around the source. The first (Region A) is a symmetric ring around the point source, starting at 25arcsec and extending to ~50arcsec. We argue that Region A is a dust scattering halo. The second (Region B) has an asymmetrical shape extending between 50arcsec and 150arcsec, and is detected both in the pre- and post-outburst data. We argue that this region is a possible magnetar wind nebula (MWN). The X-ray efficiency of the MWN with respect to the rotation energy loss is substantially higher than those of rotation powered pulsars: $\eta_{\rm X}\equiv L_{\rm MWN,0.5-8 keV}/\dot{E}_{\rm rot}\approx0.7$. The higher efficiency points to a different energy source for the MWN of Swift J1834.9-0846, most likely bursting activity of the magnetar, powered by its high magnetic field, B=1.4x10^14 G.Comment: 10 pages, 10 figures, accepted for publication in Ap

On the Complexity of Temporal-Logic Path Checking

Given a formula in a temporal logic such as LTL or MTL, a fundamental problem is the complexity of evaluating the formula on a given finite word. For LTL, the complexity of this task was recently shown to be in NC. In this paper, we present an NC algorithm for MTL, a quantitative (or metric) extension of LTL, and give an NCC algorithm for UTL, the unary fragment of LTL. At the time of writing, MTL is the most expressive logic with an NC path-checking algorithm, and UTL is the most expressive fragment of LTL with a more efficient path-checking algorithm than for full LTL (subject to standard complexity-theoretic assumptions). We then establish a connection between LTL path checking and planar circuits, which we exploit to show that any further progress in determining the precise complexity of LTL path checking would immediately entail more efficient evaluation algorithms than are known for a certain class of planar circuits. The connection further implies that the complexity of LTL path checking depends on the Boolean connectives allowed: adding Boolean exclusive or yields a temporal logic with P-complete path-checking problem

Optical transition probabilites and compositional dependence of Judd-Ofelt parameters of Er3+ ions in fluoroindate glass

Fluoroindate glasses containing 1, 2, 3, and 4 mol% ErF3 were prepared in a dry box under an argon atmosphere. Absorption spectra of these glasses at room temperature were obtained. The Judd-Ofelt parameters Omegalambda (lambda = 2, 4, 6) for f-f transitions of Er3+ ions as well as transition probabilities, branching ratios, radiative lifetimes, and peak cross-sections for stimulated emission of each band were determined. The concentration effect on the intensities is analyzed. The optical properties of the fluoroindate glasses doped with Er3+ ions are compared with those of other glasses described in the literature

Optimizing DC Microgrid Systems for Efficient Electric Vehicle Battery Charging in Ain El Ibel, Algeria

In addressing the critical challenge of developing sustainable energy solutions for electric vehicle (EV) battery charging, this study introduces an innovative direct current (DC) microgrid system optimized for areas with high solar irradiance, such as Ain El Ibel, Djelfa. The research confronts two primary difficulties: maximizing solar energy utilization in the microgrid system and ensuring system stability and response accuracy for reliable EV charging. To tackle these challenges, the study presents two original achievements. Firstly, it develops a neural network-enhanced Maximum Power Point Tracking (MPPT) controller, which is further optimized with Particle Swarm Optimization (PSO) to increase the efficiency of solar energy capture. Secondly, it refines the system's reliability through the advanced calibration of a Fractional Order Proportional-Integral (FOPI) controller using the Grey Wolf Optimization (GWO) technique, marking a notable improvement in microgrid system stability and response accuracy. The integration of a solar panel array, battery storage, and a supercapacitor, coupled with these advanced optimization techniques, exemplifies a significant leap forward in enhancing efficiency and reliability of EV battery charging through renewable energy sources. Comprehensive simulation and evaluation of the system underscore its superiority over conventional methods, demonstrating the effectiveness of combining neural network-based optimization with PSO and GWO. This breakthrough not only advances the field of renewable energy, particularly for solar-powered EV charging stations, but also aligns with global efforts towards sustainable transportation solutions

Présentation atypique d’une granulomatose avec polyangeite: à propos d’une observation pédiatrique

La granulomatose avec polyangéite (GPA) est une vascularite nécrosante systémique, caractérisée par une inflammation granulomateuse, une nécrose tissulaire et une vascularite touchant les vaisseaux de moyen et, surtout, de petit calibre, elle touche rarement l'enfant

International consensus (ICON) on treatment of sudden sensorineural hearing loss

© 2018 Elsevier Masson SAS Sudden sensorineural hearing loss (SSNHL) is a common and alarming symptom that often prompts an urgent visit to an ENT specialist. Treatment of SSNHL remains one of the most problematic issues for contemporary otorhinolaryngology: although many meta-analyses and national guidelines have been issued, management is not standardized in terms of medical treatment, and duration and route of administration. We present several methodological suggestions for the study of treatments for SSNHL. These were developed from the existing level of evidence of the main treatments used in SSNHL by experts who convened at the IFOS 2017 ENT World Congress in Paris, France. All panelists agreed that one of the main limitations present in studies on SSNHL is related to the wide heterogeneity, which characterizes both the initial hearing deficit and the amount of hearing recovery. Although evidence of the efficacy of systemic steroids cannot be considered as strong enough to recommend their use, it is still the most widespread primary therapy and can be considered as the current standard of care. Therefore, systemic steroids stand as an adequate control for any innovative treatment. To reduce the number of subjects we suggest that the inclusion criteria should be restricted to moderate to profound levels of hearing loss. The efficacy of trans-tympanic steroids as a salvage therapy was suggested in several reports on small populations and needs to be confirmed with larger randomized controlled trials

Proposed treatment strategy for reactive hypoglycaemia

Background/aim: Managing reactive hypoglycaemia (RH) poses challenges due to limited and often ineffective treatment options. We report a case series and draw on this to propose a stepwise treatment approach consisting of lifestyle modifications, metformin, GLP-1 analogues, and the use of flash glucose monitoring technology. Method: A retrospective review was conducted to analyse the management of 11 cases presenting with recurrent RH symptoms. Result: Two patients experienced successful resolution of symptoms through lifestyle modifications. Metformin alone was effective in treating seven out of nine patients who received pharmacological treatment. Two patients with previous upper gastrointestinal surgery showed a partial response to metformin and benefited further from additional long-acting GLP-1 analogue. Pharmacological intervention led to significant reductions in insulin and C-peptide levels in repeat mixed meal tolerance tests (P-values 0.043 for insulin and 0.006 for C-peptide). Finally, flash glucose monitoring technology was useful in early detection and preventing episodes of hypoglycaemia in one of these patients with persistent symptoms. Conclusion: These findings highlight the potential efficacy of escalated treatment strategies for RH, including the use of metformin, GLP-1 analogues, and flash glucose monitoring technology

Structure and Microstructure Properties of Ball Milled Fe-Zn

Nanocrystalline Fe10 %Zn and Fe30 %Zn alloys have been prepared from pure elemental powders by mechanical alloying processing in a high energy planetary ball-mill. Microstructural, structural, and magnetic characterizations of the powders were investigated by X-ray diffraction, and vibrating sample magnometer. The crystallite size reduction to the nanometer scale is accompanied by an increase in the atomic level strain. The reaction between Fe and Zn leads to the formation of a bcc Fe(Zn) solid solution with a lattice parameter close to (0.2912 nm for Fe30 %Zn and 0,2885 nm for Fe10 %Zn) after 5 h of milling. The complete dissolution of the elemental Zn powders in the a-Fe lattice gives rise to the formation of a highly disordered Fe(Zn) solid solution, where a-Fe(Zn) nanograins have a crystallite size of (229,29 Å for Fe10 %Zn (24 h) 30,09 Å for Fe30 %Zn (24 h), on prolonged milling time. The coercivity and magnetization values are 18,90 (Fe10 %Zn)Oe and 26,59 (Fe30 %Zn) emu/g, respectively, after 24 h of milling. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3514

Blue and green upconversion in Er(3+)-doped fluoroindate glasses

The upconversion properties of Er3+ in fluoroindate bulk glasses (composition: 40InF3-20ZnF2-16BaF2-(20-x)SrF2-2GaF3-2NaF-xErF3 with x=1,2,3 and 4 mole %) are investigated, following F-4(9/2) excitation with a red krypton laser. A strong green and a weaker blue luminescence is observed at room temperature corresponding to emissions from the thermally coupled S-4(3/2) and H-2(11/2) bands and the H-2(9/2) level respectively. Resonant energy transfer processes involving two excited erbium ions and a two-step absorption process are proposed to explain the upconversion phenomena. The emission intensities depend on the excitation power as P(exc)n with 1.5 less-than-or-equal-to n less-than-or-equal-to 1.7 for the green and 1.6 less-than-or-equal-to n less-than-or-equal-to 1.9 for the blue emission. The decay times and the relative intensities of the luminescences are also studied as a function of Er3+ concentration