12 research outputs found
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
Photoacoustic and optical properties of zinc-stannate thin films
Thin films of single-phase zinc-stannate (Zn2SnO4) were grown by rf magnetron sputtering onto glass substrates. Transmission in the visible range was measured allowing determination of the energy gap and thickness of analyzed thin film samples using interference fringes. The photoacoustic phase and amplitude spectra of all samples were measured as a function of the laser beam modulating frequency using a transmission detection configuration. Fitting of experimental data enabled calculation of thermal diffusivity, the coefficient of minority carrier diffusion, their mobility and lifetime
CD34-subsets as predictors of marrow repopulating or regenerative potential of stem cells: Paradigm of hierarchical vs. coexisting cellular compartments
Far infrared properties of PbTe doped with cerium
Single crystal samples of lead telluride doped with cerium were made using the Bridgman method. Far infrared reflectivity spectra in the temperature range from 10 to 300K are presented. The experimental data were numerically analyzed using a fitting procedure based on the plasmon-phonon interaction model and optical parameters were determined. Two additional local modes were observed at about 138 and 337 cm(-1). The origin of these local vibrational impurity modes was discussed
Homogeneity of the Hb Lepore gene in FR Yugoslavia
Screening analysis of Yugoslav patients with suspected thalassemia syndromes in last 4 years revealed six patients who were Hb Lepore carriers. Three were compound heterozygotes for Hb Lepore and Ī²-thalassemia, and they were affected with a thalassemia major syndrome. Family studies revealed 12 heterozygous relatives. All heterozygous carriers of Hb Lepore had a clinical phenotype of thalassemia trait. The detection of Hb Lepore was carried out by electrophoresis on cellulose acetate and confirmed by gap-polymerase chain reaction analysis of patients' DNA. Sequence analysis of all the Hb Lepore genes showed the same DNA sequence, indicating that the mutation was of the Hb Lepore-Boston-Washington type. Moreover, a single base substitution within the second intervening sequence [IVS-II-74 (GāT)] was detected in all analyzed hybrid genes. The molecular characteristics of this homogeneity represent additional data for the probable Balkan origin of this mutation
Molecular basis of Thalassemia syndromes in Serbia and Montenegro
This study reports the molecular characterization of thalassemia syndromes in Serbian and Montenegrin populations. We identified eight beta-thalassemia mutations [codon 39 (C - gt T), IVS-I-110 (G - gt A), IVS-II-745 (C - gt G), codon 44 (-C), -87 (C - gt G), IVS-II-1 (G - gt A), IVS-I-6 (T - gt C), IVS I-1 (G - gt A)] in 70 members of 29 families using polymerase chain reaction, reverse dot blot, amplification refractory mutation system and direct sequencing analysis. Hemoglobin (Hb) Lepore was found to be the most common cause of the thalassemia phenotype. Hb Sabine and alpha-thalassemia were detected as well. We also studied beta-globin gene cluster haplotypes and their association with the most common mutations. A novel haplotype associated with the Hb Lepore gene was identified. The results presented herein allowed the implementation of a prenatal diagnosis program in Serbia and Montenegro