25 research outputs found
Spectroscopy of high proper motion stars in the ground--based UV
Based on high quality spectral data (spectral resolution R>60000) within the
wavelength range of 3550-5000 AA we determined main parameters (effective
temperature, surface gravity, microturbulent velocity, and chemical element
abundances including heavy metals from Sr to Dy) for 14 metal-deficient G-K
stars with large proper motions. The stars we studied have a wide range of
metallicity: [Fe/H]=-0.3 \div -2.9. Abundances of Mg, Al, Sr and Ba were
calculated with non-LTE line-formation effects accounted for. Abundances both
of the radioactive element Th and r-process element Eu were determined using
synthetic spectrum calculations. We selected stars that belong to different
galactic populations according to the kinematical criterion and parameters
determined by us. We found that the studied stars with large proper motions
refer to different components of the Galaxy: thin, thick disks and halo. The
chemical composition of the star BD+80 245 located far from the galactic plane
agrees with its belonging to the accreted halo. For the giant HD115444 we
obtained [Fe/H]=-2.91, underabundance of Mn, overabundance of heavy metals from
Ba to Dy, and, especially high excess of the r-process element Europium:
[Eu/Fe]=+1.26. Contrary to its chemical composition typical for halo stars,
HD115444 belongs to the disc population according to its kinematic parameters.Comment: 16 pages, 4 figures, 5 tables, "UV Universe-2010 (2nd NUVA Symposium)
conference
Binary and Millisecond Pulsars
We review the main properties, demographics and applications of binary and
millisecond radio pulsars. Our knowledge of these exciting objects has greatly
increased in recent years, mainly due to successful surveys which have brought
the known pulsar population to over 1700. There are now 80 binary and
millisecond pulsars associated with the disk of our Galaxy, and a further 103
pulsars in 24 of the Galactic globular clusters. Recent highlights have been
the discovery of the first ever double pulsar system and a recent flurry of
discoveries in globular clusters, in particular Terzan 5.Comment: 77 pages, 30 figures, available on-line at
http://www.livingreviews.org/lrr-2005-
Case Reports Acute renal failure following multiple wasp bites
(Key words: wasp bites, acute renal failure
Multicentric Castleman disease of hyaline vascular variant presenting with unusual systemic manifestations: a case report
Abstract Background Castleman disease is a rare lymphoproliferative disorder presenting with localized or disseminated lymphadenopathy and systemic manifestations. It can be categorized in numerous ways, such as unicentric versus multicentric, histopathological variants (hyaline-vascular, plasma cell, and mixed), or subtypes based on causative viral infections (human immunodeficiency virus, human herpesvirus-8, or Kaposi sarcoma herpesvirus). Presentation ranges from asymptomatic to symptoms involving multiple organs. Even though the exact mechanism of pathogenesis is unknown, treatment is directed toward possible etiologies such as interleukin-6, cluster of differentiation 20, and viral agents. Case presentation A 36-year-old Sri Lankan woman presented with generalized body swelling and foamy urine of 2 weeks’ duration. Examination revealed pallor; generalized edema; axillary, cervical, and inguinal lymphadenopathy; hypertension; and hepatomegaly. Investigations showed bicytopenia, nephrotic range proteinuria with hypoalbuminemia, hypogammaglobulinemia, and features of hyaline-vascular type Castleman disease in a lymph node biopsy. She was managed with rituximab and had good clinical improvement. Conclusions Castleman disease has a broad spectrum of clinical manifestations, disease pathogeneses, and associations and/or complications. Medical professionals need to be familiar with this spectrum because timely diagnosis and aggressive targeted therapy are the cornerstones of managing these patients