454 research outputs found
Radio Planetary Nebulae in the Magellanic Clouds
We present preliminary results of our deep Australia Telescope Compact Array
(ATCA) radio-continuum survey of the Magellanic Clouds Planetary Nebulae.Comment: 2 pages 1 figure, to appear in Planetary Nebulae an Eye to the Future
Proceedings IAU Symposium No. 28
Radio Continuum Study of Supernova Remnants in the Large Magellanic Cloud - SNR J0519-6926
We present the results of new high resolution ATCA observations of SNR
J0519-6926. We found that this SNR exhibits a typical "horseshoe" appearance
with alpha = -0.55 +- 0.08 and D=28+-1 pc. No polarization (or magnetic fields)
are detected to a level of 1%. This is probably due to a relatively poor
sampling of the uv plane caused be observing in "snap-shot" mode.Comment: 6 pages 4 figures, to be published in Serbian Astronomical Journa
Dermatoglyphics as a possible morphological biomarker in myopia: analysis of finger ridge counts and fluctuating asymmetry
Background: The aim of this study is to provide the first analysis of finger ridge counts and fluctuating asymmetry in myopia, in order to evaluate dermatoglyphic role as a morphological biomarker.
Materials and methods: Study sample consisted of 102 participants recruited from freshman students’ population of the University of Priština-Kosovska Mitro- vica. Prints were taken by standard ink and paper method. Differences in mean ridge counts between examined groups were analysed by ANOVA analysis of variance. Fluctuating asymmetry assessment was performed by using correlation method (p < 0.05).
Results: Analysis has identified myopic males as the group with the most pro- minent differences of examined dermatoglyphic parameters. Myopic males, compared to controls, have significantly higher ridge counts for left and right ring and little finger, as well as total ridge count. Also, this group has recorded significant difference in fluctuating asymmetry correlation score for middle finger, and borderline significance for thumb and ring finger.
Conclusions: Overall findings of this study have indicated that dermatoglyphics might serve as a morphological biomarker, especially in myopic males, selecting them as the group with dermatoglyphic differences that might be suggestive of higher developmental instability. Although promising, the present results should be considered as preliminary until future investigations replicate them in a larger sample.
Radio-Continuum Observations Of Small, Radially Polarised Supernova Remnant J0519-6902 In The Large Magellanic Cloud
We report on new Australian Telescope Compact Array (ATCA) observations of
SNR J0519-6902. The Supernova Remnant (SNR) is small in size (~8 pc) and
exhibits a typical SNR spectrum of alpha = -0.53 +- 0.07, with steeper spectral
indices found towards the northern limb of the remnant. SNR J0519-6902 contains
a low level of radially orientated polarisation at wavelengths of 3 & 6 cm,
which is characteristic of younger SNRs. A fairly strong magnetic field was
estimated of ~171 microG. The remnant appears to be the result of a typical
Type Ia supernovae, sharing many properties as another small and young Type Ia
LMC SNR, J0509-6731.Comment: 10 pages 7 figures, submitted to Serbian Astronomical Journa
Stability Constants Determination of Mandelate Complexes of Cobalt(II), Nickel(II) and Zinc(II)
Stability constants of mandelate (2-phenyl-2-hydroxyacetate)
complexes of cobalt(II), nickel(II) and zinc(II) were determined.
potentiometrically using glass and quinhydrone electrodes at
25.0 ± 0.1 aC and ionic strength 2 mole dm" (sodium perchlorate).
The numerical values of stability constants were evaluated from
experimental data by a computer program based on a weighted
least squares method
Determination of Methoxyl and Ethoxyl Groups in Organic Compounds
Determination of methoxyl and ethoxyl groups in organic compounds according to Zeisel \u27s method frequently yielded somewhat higher analytical values. This usually occured when the methyl or ethyl iodide was insufficiently purified from matters which hindered their determination. Liquid-filled washers are used for the elimination of these matters. When the liquids in the washer were replaced by solid ascarite, and the determination carried under a stream of nitrogen or air, no errors occurred . Besides, if a layer of anhydrone was added to the washer containing ascarite, the carbon and hydrogen content of the obtained methyl or ethyl iodide could be determined, and it could thus be ascertained whether the organic compound contained methoxyl groups, ethoxyl groups, or a mixture of both
Chelating Properties of 2,5-Dibenzoyl-3,4-dihydroxy Selenophene*
In this Laboratory several 2,5-diacyl-3,4-dihydroxy selenophenes (I) have earlier been prepared by reacting, a, y, d, <; -tetraketones with selenium-dioxide1
Multifrequency radio observations of SNR J0536-6735 (N 59B) with associated pulsar
We present a study of new Australian Telescope Compact Array (ATCA)
observations of supernova remnant, SNR J0536-6735. This remnant appears to
follow a shell morphology with a diameter of D=36x29 pc (with 1 pc uncertainty
in each direction). There is an embedded Hii region on the northern limb of the
remnant which made various analysis and measurements (such as flux density,
spectral index and polarisation) difficult. The radio-continuum emission
followed the same structure as the optical emission, allowing for extent and
flux density estimates at 20 cm. We estimate a surface brightness for the SNR
at 1 GHz of 2.55x10^-21 W m^-2 Hz^-1 sr^-1. Also, we detect a distinctive
radio-continuum point source which confirms the previous suggestion of this
remnant being associated with a pulsar wind nebulae (PWN). The tail of this
remnant isn't seen in the radio-continuum images and is only seen in the
optical and X-ray images.Comment: 10 pages 4 figures, accepted for publication in SA
Derivative pricing for a multi-curve extension of the Gaussian, exponentially quadratic short rate model
The recent financial crisis has led to so-called multi-curve models for the
term structure. Here we study a multi-curve extension of short rate models
where, in addition to the short rate itself, we introduce short rate spreads.
In particular, we consider a Gaussian factor model where the short rate and the
spreads are second order polynomials of Gaussian factor processes. This leads
to an exponentially quadratic model class that is less well known than the
exponentially affine class. In the latter class the factors enter linearly and
for positivity one considers square root factor processes. While the square
root factors in the affine class have more involved distributions, in the
quadratic class the factors remain Gaussian and this leads to various
advantages, in particular for derivative pricing. After some preliminaries on
martingale modeling in the multi-curve setup, we concentrate on pricing of
linear and optional derivatives. For linear derivatives, we exhibit an
adjustment factor that allows one to pass from pre-crisis single curve values
to the corresponding post-crisis multi-curve values
HFPK 334: An unusual Supernova Remnant in the Small Magellanic Cloud
We present new Australia Telescope Compact Array (ATCA) radio-continuum and
XMM-Newton/Chandra X-ray Observatory (CXO) observations of the unusual
supernova remnant HFPK 334 in the Small Magellanic Cloud (SMC). The remnant
follows a shell type morphology in the radio-continuum and has a size of
20~pc at the SMC distance. The X-ray morphology is similar, however, we
detect a prominent point source close to the center of the SNR exhibiting a
spectrum with a best fit powerlaw with a photon index of . This central point source is most likely a background object and cannot
be directly associated with the remnant. The high temperature, nonequilibrium
conditions in the diffuse region suggest that this gas has been recently
shocked and point toward a younger SNR with an age of years.
With an average radio spectral index of we find that an
equipartition magnetic field for the remnant is 90~G, a value
typical of younger SNRs in low-density environments. Also, we report detection
of scattered radio polarisation across the remnant at 20~cm, with a peak
fractional polarisation level of 255\%.Comment: 19 pages, 6-figures, submitted to A
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