Photospheric plasma and magnetic field dynamics during the formation of solar AR 11190

The Sun features on its surface typical flow patterns called the granulation, mesogranulation, and supergranulation. These patterns arise due to convective flows transporting energy from the interior of the Sun to its surface. In this paper we will shed light on the interaction between the convective flows in large-scale cells as well as the large-scale magnetic fields in active regions, and investigate in detail the statistical distribution of flow velocities during the evolution and formation of National Oceanic and Atmospheric Administration (NOAA) active region 11190. To do so, we employed local correlation tracking methods on data obtained by the Solar Dynamics Observatory (SDO) spacecraft in the continuum as well as on processed line-of-sight (LOS) magnetograms. We find that the flow fields in an active region can be modelled by a two-component distribution. One component is very stable, follows a Rayleigh distribution, and can be assigned to the background flows, whilst the other component is variable in strength and velocity range and can be attributed to the flux emergence visible both in the continuum maps as well as magnetograms. Generally, the plasma flows, as seen by the distribution of the magnitude of the velocity, follow a Rayleigh distribution even through the time of formation of active regions. However, at certain moments of large-scale fast flux emergence, a second component featuring higher velocities is formed in the velocity magnitudes distribution. The plasma flows are generally highly correlated to the motion of magnetic elements and vice versa except during the times of fast magnetic flux emergence as observed by rising magnetic elements. At these times, the magnetic fields are found to move faster than the corresponding plasma.Comment: 15 pages, 11 figures, 5 equations. Accepted for publication in Astronomy and Astrophysics (A&A

Exploring magnetic field properties at the boundary of solar pores: A comparative study based on SDO-HMI observations

The Sun's magnetic fields play an important role in various solar phenomena. Solar pores are regions of intensified magnetic field strength compared to the surrounding photospheric environment, and their study can help us better understand the properties and behaviour of magnetic fields in the Sun. Up to now, there exists only a single study on magnetic field properties at the boundary region of a pore. Therefore, the main goal of this work is to increase the statistics of magnetic properties determining the pore boundary region. We analyse six solar pores using data from the Helioseismic and Magnetic Imager instrument on board the Solar Dynamics Observatory. We apply image processing techniques to extract the relevant features of the solar pores and determine the boundary conditions of the magnetic fields. We find the maximal vertical magnetic field values on the boundaries of the studied solar pores to range from 1400~G to 1600~G, with a standard deviation between 7.8\% and 14.8\%. These values are lower than those reported in the mentioned preceding study. However, this can be explained by differences in spatial resolution as well as the type of data we used. The vertical magnetic field is an important factor in determining the boundary of solar pores, and it plays a more relevant role than the intensity gradient. The obtained information will be useful for future studies on the formation and evolution of magnetic structures of the Sun. Additionally, this study highlights the importance of high spatial resolution data for the purpose of accurately characterising the magnetic properties of solar pores.Comment: 9 pages, 7 figures. Accepted for publication in Astronomy and Astrophysics (A&A

Detection of small convective patterns in observations and simulations

Recent results from high resolution solar granulation observations indicate the existence of a population of small granular cells on scales below 600 km in diameter, located in the intergranular lanes. We studied a set of Hinode SOT images and high resolution radiation hydrodynamics simulations in order to analyze small granular cells and to study their physical properties. An automated image segmentation algorithm specifically adapted to high resolution simulations for the identification of granules was developed. The algorithm was also used to analyze and compare physical quantities provided by the simulation and the observations. We found that small granules make a distinct contribution to the total area of granules. Both in observations and simulations, small granular cells exhibit on average lower intensities and vertical velocities

Parallelization of the SIR code

A high-resolution 3-dimensional model of the photospheric magnetic field is essential for the investigation of small-scale solar magnetic phenomena. The SIR code is an advanced Stokes-inversion code that deduces physical quantities, e.g. magnetic field vector, temperature, and LOS velocity, from spectropolarimetric data. We extended this code by the capability of directly using large data sets and inverting the pixels in parallel. Due to this parallelization it is now feasible to apply the code directly on extensive data sets. Besides, we included the possibility to use different initial model atmospheres for the inversion, which enhances the quality of the results

Concomitant Carcinoma in situ in Cystectomy Specimens Is Not Associated with Clinical Outcomes after Surgery

Objective: The aim of this study was to externally validate the prognostic value of concomitant urothelial carcinoma in situ (CIS) in radical cystectomy (RC) specimens using a large international cohort of bladder cancer patients. Methods: The records of 3,973 patients treated with RC and bilateral lymphadenectomy for urothelial carcinoma of the bladder (UCB) at nine centers worldwide were reviewed. Surgical specimens were evaluated by a genitourinary pathologist at each center. Uni- and multivariable Cox regression models addressed time to recurrence and cancer-specific mortality after RC. Results: 1,741 (43.8%) patients had concomitant CIS in their RC specimens. Concomitant CIS was more common in organ-confined UCB and was associated with lymphovascular invasion (p < 0.001). Concomitant CIS was not associated with either disease recurrence or cancer-specific death regardless of pathologic stage. The presence of concomitant CIS did not improve the predictive accuracy of standard predictors for either disease recurrence or cancer-specific death in any of the subgroups. Conclusions: We could not confirm the prognostic value of concomitant CIS in RC specimens. This, together with the discrepancy between pathologists in determining the presence of concomitant CIS at the morphologic level, limits the clinical utility of concomitant CIS in RC specimens for clinical decision-making. Copyright (C) 2011 S. Karger AG, Base

Optical identification using imperfections in 2D materials

The ability to uniquely identify an object or device is important for authentication [1]. Imperfections, locked into structures during fabrication, can be used to provide a fingerprint that is challenging to reproduce. In this paper, we propose a simple optical technique to read unique information from nanometer-scale defects in 2D materials. Imperfections created during crystal growth or fabrication lead to spatial variations in the bandgap of 2D materials that can be characterized through photoluminescence measurements. We show a simple setup involving an angle- adjustable transmission filter, simple optics and a CCD camera can capture spatially- dependent photoluminescence to produce complex maps of unique information from 2D monolayers. Atomic force microscopy is used to verify the origin of the optical signature measured, demonstrating that it results from nanometer-scale imperfections. This solution to optical identification with 2D materials could be employed as a robust security measure to prevent counterfeiting

Express determination of ceftriaxone in biological and medicinal media

Currently, a pressing problem is the implementation of drug monitoring, which provides the choice of an adequate individual dose and pattern for the use of antibiotics to improving the efficiency and safety of treatment Planar unmodified and modified polyaniline (PANi), NiZnFeO nanoparticles and their binary mixtures potentiometric sensors based on tetradecylammonium (TDA) associations with complex compounds silver (I) - ceftriaxone (Ag(I)-Ceftr) are proposed for the express quantitative determination of ceftriaxone in the biological fluids of organism and medicines. The use of planar sensors for determination of ceftriaxone in oral fluid and drugs of various manufacturers and shelf life is shown.В настоящее время актуальной проблемой является осуществление лекарственного мониторинга, который обеспечивает выбор адекватной индивидуальной дозы и схемы применения антибиотиков для повышения эффективности и безопасности лечения. Для экспрессного количественного определения цефтриаксона в биологических жидкостях организма и лекарственных препаратах предложены планарные немодифицированные и модифицированные полианилином(ПАНи), наночастицами NiZnFeO и их бинарными смесями потенциометрические сенсоры на основе ассоциатов тетрадециламмония (ТДА) с комплексными соединениями серебро (I) – цефтриаксон(Ag(I)-Ceftr). Показано применение планарных сенсоров для определения цефтриаксона в ротовой жидкости и препаратах различных производителей и сроков годности