3,342 research outputs found
Tinea Cruris Resurgence in Male Genitalia: A Case Report
Tinea infection is a very common disease, but that of the male genitalia is said to be rare. We present a 45 year old male patient suffering from tinea cruris, with lesions extremely chronic and progressive. The patients gave history of empirical treatment and under dosage of antifungal agents with resurgence of the infection. Culture of scrapings from the lesion yielded Epidermophyton floccosum. The case resolved completely with topical tioconazole and oral administration of 50mg fluconazole 3 times a week for six weeks. Patient’s treatment should therefore be guided by laboratory diagnosis and patients should comply with prescribed dosage for better results.Keywords: Tinea cruris, Resurgence, Epidermophyton floccosum, Treatment
Evolution, nucleosynthesis and yields of low mass AGB stars at different metallicities (II): the FRUITY database
By using updated stellar low mass stars models, we can systematically
investigate the nucleosynthesis processes occurring in AGB stars, when these
objects experience recurrent thermal pulses and third dredge-up episodes. In
this paper we present the database dedicated to the nucleosynthesis of AGB
stars: the FRUITY (FRANEC Repository of Updated Isotopic Tables & Yields)
database. An interactive web-based interface allows users to freely download
the full (from H to Bi) isotopic composition, as it changes after each third
dredge-up episode and the stellar yields the models produce. A first set of AGB
models, having masses in the range 1.5 < M/Msun < 3.0 and metallicities 1e-3 <
Z < 2e-2, is discussed here. For each model, a detailed description of the
physical and the chemical evolution is provided. In particular, we illustrate
the details of the s-process and we evaluate the theoretical uncertainties due
to the parametrization adopted to model convection and mass loss. The resulting
nucleosynthesis scenario is checked by comparing the theoretical [hs/ls] and
[Pb/hs] ratios to those obtained from the available abundance analysis of
s-enhanced stars. On the average, the variation with the metallicity of these
spectroscopic indexes is well reproduced by theoretical models, although the
predicted spread at a given metallicity is substantially smaller than the
observed one. Possible explanations for such a difference are briefly
discussed. An independent check of the third dredge-up efficiency is provided
by the C-stars luminosity function. Consequently, theoretical C-stars
luminosity functions for the Galactic disk and the Magellanic Clouds have been
derived. We generally find a good agreement with observations.Comment: Accepted for Publication on The Astrophysical Journal Supplement
Magnetic molecules created by hydrogenation of Polycyclic Aromatic Hydrocarbons
Present routes to produce magnetic organic-based materials adopt a common
strategy: the use of magnetic species (atoms, polyradicals, etc.) as building
blocks. We explore an alternative approach which consists of selective
hydrogenation of Polycyclic Aromatic Hydrocarbons. Self-Consistent-Field (SCF)
(Hartree-Fock and DFT) and multi-configurational (CISD and MCSCF) calculations
on coronene and corannulene, both hexa-hydrogenated, show that the formation of
stable high spin species is possible. The spin of the ground states is
discussed in terms of the Hund rule and Lieb's theorem for bipartite lattices
(alternant hydrocarbons in this case). This proposal opens a new door to
magnetism in the organic world.Comment: 6 pages, 4 figures and 2 table
Deep Mixing in Evolved Stars. II. Interpreting Li Abundances in RGB and AGB Stars
We reanalyze the problem of Li abundances in red giants of nearly solar
metallicity. After an outline of the problems affecting our knowledge of the Li
content in low-mass stars (M<3Mo), we discuss deep-mixing models for the RGB
stages suitable to account for the observed trends and for the correlated
variations of the carbon isotope ratio; we find that Li destruction in these
phases is limited to masses below about 2.3 Mo. Subsequently, we concentrate on
the final stages of evolution for both O-rich and C-rich AGB stars. Here, the
constraints on extra-mixing phenomena previously derived from heavier nuclei
(from C to Al), coupled to recent updates in stellar structure models
(including both the input physics and the set of reaction rates used), are
suitable to account for the observations of Li abundances below A(Li)= log
e(Li) = 1.5 (and sometimes more). Also their relations with other
nucleosynthesis signatures of AGB phases (like the abundance of F, the C/O and
12C/13C ratios) can be explained. This requires generally moderate efficiencies
(\dot M <= 0.3 - 0.5 x 10^-6 Mo/yr) for non-convective mass transport. At such
rates, slow extra-mixing does not modify remarkably Li abundances in early-AGB
phases; on the other hand, faster mixing encounters a physical limit in
destroying Li, set by the mixing velocity. Beyond this limit, Li starts to be
produced; therefore its destruction on the AGB is modest. Li is then
significantly produced by the third dredge up. We also show that effective
circulation episodes, while not destroying Li, would easily bring the 12C/13C
ratios to equilibrium, contrary to the evidence in most AGB stars, and would
burn F beyond the limits shown by C(N) giants. Hence, we do not confirm the
common idea that efficient extra-mixing drastically reduces the Li content of
C-stars with respect to K-M giants.Comment: 56 pages, 21 13 figures, ApJ submitte
Galactic Cosmic Rays from Superbubbles and the Abundances of Lithium, Beryllium, and Boron
In this article we study the galactic evolution of the LiBeB elements within
the framework of a detailed model of the chemical evolution of the Galaxy that
includes galactic cosmic ray nucleosynthesis by particles accelerated in
superbubbles. The chemical composition of the superbubble consists of varying
proportions of ISM and freshly supernova synthesized material. The
observational trends of 6 LiBeB evolution are nicely reproduced by models in
which GCR come from a mixture of 25% of supernova material with 75% of ISM,
except for 6 Li, for which maybe an extra source is required at low
metallicities. To account for 7 Li evolution several additional sources have
been considered (neutrino-induced nucleosynthesis, nova outbursts, C-stars).
The model fulfills the energetic requirements for GCR acceleration.Comment: 25 pages, 9 figures. Accepted for publication in the Astrophysical
Journa
Fluorine Abundances in the Globular Cluster M 4
We present chemical abundances for the elements carbon, sodium, and fluorine
in 15 red giants of the globular cluster M 4, as well as six red giants of the
globular cluster Centauri. The chemical abundances were calculated in
LTE via spectral synthesis. The spectra analyzed are high-resolution spectra
obtained in the near-infrared region around 2.3m with the Phoenix
spectrograph on the 8.1m Gemini South Telescope, the IGRINS spectrograph on the
McDonald Observatory 2.7m Telescope, and the CRIRES spectrograph on the ESO
8.2m Very Large Telescope. The results indicate a significant reduction in the
fluorine abundances when compared to previous values from the literature for M
4 and Centauri, due to a downward revision in the excitation
potentials of the HF(1-0) R9 line used in the analysis. The fluorine abundances
obtained for the M 4 red giants are found to be anti-correlated with those of
Na, following the typical pattern of abundance variations seen in globular
clusters between distinct stellar populations. In M 4, as the Na abundance
increases by +0.4 dex, the F abundance decreases by -0.2 dex. A
comparison with abundance predictions from two sets of stellar evolution models
finds that the models predict somewhat less F depletion (-0.1 dex) for
the same increase of +0.4 dex in Na
Dynamics of a structured slug population model in the absence of seasonal variation
We develop a novel, nonlinear structured population model for the slug Deroceras reticulatum, a highly significant agricultural pest of great economic impact, in both organic and non-organic settings. In the absence of seasonal variations, we numerically explore the effect of life history traits that are dependent on an individual's size and measures of population biomass. We conduct a systematic exploration of parameter space and highlight the main mechanisms and implications of model design. A major conclusion of this work is that strong size dependent predation significantly adjusts the competitive balance, leading to non-monotonic steady state solutions and slowly decaying transients consisting of distinct generational cycles. Furthermore, we demonstrate how a simple ratio of adult to juvenile biomass can act as a useful diagnostic to distinguish between predated and non-predated environments, and may be useful in agricultural settings
名寄市立総合病院耳鼻咽喉科の3年間を振り返って
We present Mg abundances derived from high-resolution spectra using several MgI and two high-excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic differences in the derived abundances between the two ionization state lines. Our analysis shows that the one-dimensional local thermodynamic equilibrium (LTE) and non-LTE (N-LTE) study finds a very good agreement between these features. The [Mg/Fe] versus [Fe/H] relationship derived, despite the small sample of stars, is also in agreement with the classical figure of increasing [Mg/Fe] with decreasing metallicity. We find a significant scatter however, in the [Mg/Fe] ratio at [Fe/H] ∼ -0.6 which is currently explained as a consequence of the overlap at this metallicity of thick- and thin-disc stars, which were probably formed from material with different nucleosynthesis histories. We speculate on the possible consequences of the agreement found between Mg I and Mg II lines on the very well-known O problem in metal-poor stars. We also study the [O/Mg] ratio in the sample stars using O abundances from the literature and find that the current observations and nucleosynthetic predictions from Type II supernovae disagree. We briefly discuss some alternatives to solve this discrepancy
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