1,306 research outputs found
Magneto-acoustic waves in sunspots from observations and numerical simulations
We study the propagation of waves from the photosphere to the chromosphere of
sunspots. From time series of cospatial Ca II H (including its line blends)
intensity spectra and polarimetric spectra of Si I 1082.7 nm and He I 1083.0 nm
we retrieve the line-of-sight velocity at several heights. The analysis of the
phase difference and amplification spectra shows standing waves for frequencies
below 4 mHz and propagating waves for higher frequencies, and allows us to
infer the temperature and height where the lines are formed. Using these
observational data, we have constructed a model of sunspot, and we have
introduced the velocity measured with the photospheric Si I 1082.7 nm line as a
driver. The numerically propagated wave pattern fits reasonably well with the
observed using the lines formed at higher layers, and the simulations reproduce
many of the observed features. The observed waves are slow MHD waves
propagating longitudinally along field lines.Comment: proceedings of GONG 2010/SOHO 24 meeting, June 27 - July 2, 2010,
Aix-en-Provence, Franc
Magneto-acoustic waves in sunspots: first results from a new 3D nonlinear magnetohydrodynamic code
Waves observed in the photosphere and chromosphere of sunspots show complex
dynamics and spatial patterns. The interpretation of high-resolution sunspot
wave observations requires modeling of three-dimensional non-linear wave
propagation and mode transformation in the sunspot upper layers in realistic
spot model atmospheres. Here we present the first results of such modeling. We
have developed a 3D non-linear numerical code specially designed to calculate
the response of magnetic structures in equilibrium to an arbitrary
perturbation. The code solves the 3D nonlinear MHD equations for perturbations;
it is stabilized by hyper-diffusivity terms and is fully parallelized. The
robustness of the code is demonstrated by a number of standard tests. We
analyze several simulations of a sunspot perturbed by pulses of different
periods at subphotospheric level, from short periods, introduced for academic
purposes, to longer and realistic periods of three and five minutes. We present
a detailed description of the three-dimensional mode transformation in a
non-trivial sunspot-like magnetic field configuration, including the conversion
between fast and slow magneto-acoustic waves and the Alfv\'en wave, by
calculation of the wave energy fluxes. Our main findings are the following: (1)
the conversion from acoustic to the Alfv\'en mode is only observed if the the
driving pulse is located out of the sunspot axis, but this conversion is
energetically inefficient; (2) as a consequence of the cut-off effects and
refraction of the fast magneto-acoustic mode, the energy of the evanescent
waves with periods around 5 minutes remains almost completely below the level
beta=1; (3) waves with frequencies above the cut-off propagate field-aligned to
the chromosphere and their power becomes dominating over that of evanescent
5-minute oscillations, in agreement with observations
Multi-layer study of wave propagation in sunspots
We analyze the propagation of waves in sunspots from the photosphere to the
chromosphere using time series of co-spatial Ca II H intensity spectra
(including its line blends) and polarimetric spectra of Si I 10827 and the He I
10830 multiplet. From the Doppler shifts of these lines we retrieve the
variation of the velocity along the line-of-sight at several heights. Phase
spectra are used to obtain the relation between the oscillatory signals. Our
analysis reveals standing waves at frequencies lower than 4 mHz and a
continuous propagation of waves at higher frequencies, which steepen into
shocks in the chromosphere when approaching the formation height of the Ca II H
core. The observed non-linearities are weaker in Ca II H than in He I lines.
Our analysis suggests that the Ca II H core forms at a lower height than the He
I 10830 line: a time delay of about 20 s is measured between the Doppler signal
detected at both wavelengths. We fit a model of linear slow magnetoacoustic
wave propagation in a stratified atmosphere with radiative losses according to
Newton's cooling law to the phase spectra and derive the difference in the
formation height of the spectral lines. We show that the linear model describes
well the wave propagation up to the formation height of Ca II H, where
non-linearities start to become very important.Comment: Accepted by The Astrophysical Journa
Magneto-acoustic wave energy from numerical simulations of an observed sunspot umbra
We aim at reproducing the height dependence of sunspot wave signatures
obtained from spectropolarimetric observations through 3D MHD numerical
simulations. A magneto-static sunspot model based on the properties of the
observed sunspot is constructed and perturbed at the photosphere introducing
the fluctuations measured with the \SiI\ 10827 \AA\ line. The results
of the simulations are compared with the oscillations observed simultaneously
at different heights from the \HeI\ 10830 \AA\ line, the \CaIIH\ core
and the \FeI\ blends in the wings of the \CaIIH\ line. The simulations show a
remarkable agreement with the observations. They reproduce the velocity maps
and power spectra at the formation heights of the observed lines, as well as
the phase and amplification spectra between several pair of lines. We find that
the stronger shocks at the chromosphere are accompanied with a delay between
the observed signal and the simulated one at the corresponding height,
indicating that shocks shift the formation height of the chromospheric lines to
higher layers. Since the simulated wave propagation matches very well the
properties of the observed one, we are able to use the numerical calculations
to quantify the energy contribution of the magneto-acoustic waves to the
chromospheric heating in sunspots. Our findings indicate that the energy
supplied by these waves is too low to balance the chromospheric radiative
losses. The energy contained at the formation height of the lowermost \SiI\
10827 \AA\ line in the form of slow magneto-acoustic waves is already
insufficient to heat the higher layers, and the acoustic energy which reaches
the chromosphere is around 3-9 times lower than the required amount of energy.
The contribution of the magnetic energy is even lower.Comment: Accepted for publication in The Astrophysical Journa
Signatures of the impact of flare ejected plasma on the photosphere of a sunspot light-bridge
We investigate the properties of a sunspot light-bridge, focusing on the
changes produced by the impact of a plasma blob ejected from a C-class flare.
We observed a sunspot in active region NOAA 12544 using spectropolarimetric
raster maps of the four Fe I lines around 15655 \AA\ with the GREGOR Infrared
Spectrograph (GRIS), narrow-band intensity images sampling the Fe I 6173 \AA\
line with the GREGOR Fabry-P\'erot Interferometer (GFPI), and intensity broad
band images in G-band and Ca II H band with the High-resolution Fast Imager
(HiFI). All these instruments are located at the GREGOR telescope at the
Observatorio del Teide, Tenerife, Spain. The data cover the time before,
during, and after the flare event. The analysis is complemented with
Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI)
data from the Solar Dynamics Observatory (SDO). The physical parameters of the
atmosphere at differents heights were inferred using spectral-line inversion
techniques. We identify photospheric and chromospheric brightenings, heating
events, and changes in the Stokes profiles associated to the flare eruption and
the subsequent arrival of the plasma blob to the light bridge, after traveling
along an active region loop. The measurements suggest that these phenomena are
the result of reconnection events driven by the interaction of the plasma blob
with the magnetic field topology of the light bridge.Comment: Accepted for publication in A&
Newly identified properties of surface acoustic power
The cause of enhanced acoustic power surrounding active regions, the acoustic
halo, is not as yet understood. We explore the properties of the enhanced
acoustic power observed near disk center from 21 to 27 January 2002, including
AR 9787. We find that (i) there exists a strong correlation of the enhanced
high frequency power with magnetic-field inclination, with greater power in
more horizontal fields, (ii) the frequency of the maximum enhancement increases
along with magnetic field strength, and (iii) the oscillations contributing to
the halos show modal ridges which are shifted to higher wavenumber at constant
frequency in comparison to the ridges of modes in the quiet-Sun.Comment: 16 pages, 10 figures, submitted to solar physic
OBSERVATION OF MEDICINES FOR THE TREATMENT OF DIAPER DERMATITIS ON THE PHARMACEUTICAL MARKET OF UKRAINE
Introduction
The neonatal period is the most critical age. There is a high incidence of children in the first year of life on diseases of the skin and subcutaneous tissue. Recently, we can see an increasing proportion of morbidity with atopic dermatitis (10-20%) [1], contact and diaper dermatitis (25%-50%) [5]. Most cases are associated with genetic penchant, an excessive eating of exotic vegetables and fruits, a high frequency of feeding with artificial mixtures etc. [6].
Diaper dermatitis (DD) is an inflammatory reaction of the child`s skin as a result of the mechanical, physical, chemical and microbial factors. It consists of erythema with maceration and may include papules, erosions, and even ulcerations, when severe. The convex surfaces of the newborns buttocks, genitalia, lower abdomen and upper thighs are the places of the greatest affection [3,8]. Disease can occur under conditions of: late diapers changing, mechanical friction, usage of some care products, transition from breastfeeding to artificial feeding, individual sensitivity of the child`s skin, usage of antibiotics [7,8].
Despite the wide variety of drugs that have been successfully used in dermatology, the amount of drugs for the diaper dermatitis treatment is not enough.
So, the aim of our work was to analyze the range of medicines for the treatment of DD, that are presented at the pharmaceutical market ofUkraine.
The object of the study was the information of the State register of drugs ofUkraine, formed by “State expert center of the Ministry of health ofUkraine”.
Methods of research: search, analysis, generalization and systematization of data.
Results and discussion
According to the ATC classification, the range of medicines for the treatment of diaper dermatitis belongs to the group D – dermatological products and consists of several groups: D01 (antifungals for dermatological use), D02 (emollients and protective), D03 (preparations for treatment of wounds and ulcers), D06 (antibiotics and chemotherapeutics for dermatological use) and D07 (corticosteroids, dermatological preparations) [4].
There are 18 drugs, which are used for DD treatment according to the State register of medicines (at 1 December 2016). They are divided into 5 subgroups according to the ATC-classification. Most of them are D03 group drugs (33,3%) – preparations for treatment of wounds and ulcers (“Panthecrem”,” Happyderm-Zdorovie”, “Panthenol”, “Panteхol Jadran”, “Bepanten”, “Panthenol-Ratiopharm”) and D07 (27,8%) – corticosteroids, dermatological preparations (“Betlieben”, “Hydrocortisone”, “Locoid Crelo”, “Locoid Lipokrem”, “Cutivate”).
Among the components of formulation of the studied drugs the greatest proportion belongs to such active pharmaceutical ingredients as dexpanthenol – 46,7%, zinc oxide – 20,0%, hydrocortisone – 20,0%, clotrimazole – 6,6% and fusidic acid – 6,7%.
Analysis of drugs for the DD treatment, depending on the type of dosage form (DF) showed that drugs are represented by the four DF. The greatest number have the soft dosage forms (ointments – 47,4% and creams – 42,1%).
The assortment of this group of drugs is being shaped by three national and twelve foreign manufacturers. Among Ukrainian manufacturers the lider is Public Joint-Stock Corporation (PJSC) “Fitofarm” (50%), among foreign manufacturers – “Jadran” Galenski Laboratorij d.d., Croatia (14,3%) and Temmler Italia S.r.l., Italy (14,3%).
By legal status 42% of drugs used for the treatment of diaper dermatitis are released from drugstores and their structural units with prescription [2,4].
Conclusions
There were 18 drugs, which are used for treatment of diaper dermatitis according to the State register of medicines (1 December 2016). 95% of them are intended for the treatment of both children and adults and more than 20% of drugs can be used only for children in age 3-6 months. It should also be noted that the nature of the disease is influenced by the individual characteristics of the child, this requires a differentiated approach to the choice of therapy in each case. The creation of an effective pediatric medicines both industrial production and extempore formulation according to the requirements of good manufacturing practice and good pharmacy practice is an actual problem
Does organic farming increase raspberry quality, aroma and beneficial bacterial biodiversity?
Plant-associated microbes can shape plant phenotype, performance, and productivity. Cultivation methods can influence the plant microbiome structure and differences observed in the nutritional quality of differently grown fruits might be due to variations in the microbiome taxonomic and functional composition. Here, the influence of organic and integrated pest management (IPM) cultivation on quality, aroma and microbiome of raspberry (Rubus idaeus L.) fruits was evaluated. Differences in the fruit microbiome of organic and IPM raspberry were examined by next-generation sequencing and bacterial isolates characterization to highlight the potential contribution of the resident-microflora to fruit characteristics and aroma. The cultivation method strongly influenced fruit nutraceutical traits, aroma and epiphytic bacterial biocoenosis. Organic cultivation resulted in smaller fruits with a higher anthocyanidins content and lower titratable acidity content in comparison to IPM berries. Management practices also influenced the amounts of acids, ketones, aldehydes and monoterpenes, emitted by fruits. Our results suggest that the effects on fruit quality could be related to differences in the population of Gluconobacter, Sphingomonas, Rosenbergiella, Brevibacillus and Methylobacterium on fruit. Finally, changes in fruit aroma can be partly explained by volatile organic compounds (VOCs) emitted by key bacterial genera characterizing organic and IPM raspberry fruit
Local helioseismology of sunspot regions: comparison of ring-diagram and time-distance results
Local helioseismology provides unique information about the subsurface
structure and dynamics of sunspots and active regions. However, because of
complexity of sunspot regions local helioseismology diagnostics require careful
analysis of systematic uncertainties and physical interpretation of the
inversion results. We present new results of comparison of the ring-diagram
analysis and time-distance helioseismology for active region NOAA 9787, for
which a previous comparison showed significant differences in the subsurface
sound-speed structure, and discuss systematic uncertainties of the measurements
and inversions. Our results show that both the ring-diagram and time-distance
techniques give qualitatively similar results, revealing a characteristic
two-layer seismic sound-speed structure consistent with the results for other
active regions. However, a quantitative comparison of the inversion results is
not straightforward. It must take into account differences in the sensitivity,
spatial resolution and the averaging kernels. In particular, because of the
acoustic power suppression, the contribution of the sunspot seismic structure
to the ring-diagram signal can be substantially reduced. We show that taking
into account this effect reduces the difference in the depth of transition
between the negative and positive sound-speed variations inferred by these
methods. Further detailed analysis of the sensitivity, resolution and averaging
properties of the local helioseismology methods is necessary for consolidation
of the inversion results. It seems to be important that both methods indicate
that the seismic structure of sunspots is rather deep and extends to at least
20 Mm below the surface, putting constraints on theoretical models of sunspots.Comment: 10 pages, 10 figures, submitted to Journal of Physics: Conference
Series (JPCS) GONG 2010 - SoHO 24 "A new era of seismology of the Sun and
solar-like stars", June 27 - July 2, 2010 Aix-en-Provence, Franc
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