28 research outputs found
The superimposed photospheric and stellar wind variability of the O-type supergiant alpha Cam
(Abridged) We provide empirical constraints on the different physical
components that can act to yield temporal variability in predominantly or
partially wind-formed optical lines of luminous OB stars, and thus potentially
affect the reliable determination of fundamental parameters, including
mass-loss rates via clumped winds. Using time-series spectroscopy from epochs
spread over 4 years, a case study of the O9.5 supergiant Cam is
presented. We demonstrate that the He I 5876 (2P--3D) line is an
important diagnostic for photospheric and wind variability in this star. The
optical line profiles of Cam are affected by (i) deep-seated
fluctuations close to, or at, the photosphere, (ii) atmospheric velocity
gradients, and (iii) large-scale stellar wind structure. This study provides
new empirical perspectives on accurate line-synthesis modelling of stellar wind
signatures in massive luminous stars. Using a pure Halpha line-synthesis code
we interpret maximum changes in the red-ward and peak emission of Cam
in terms of mass-loss rate differences in the range 5.1
10 to 6.5 10 M yr. However, the models
generally fail to reproduce the morphology of blueward (possibly absorptive)
regions of the profiles.Comment: Accepted for pulication in A&A; 9 pages and 8 figure
Large-scale wind structures in OB supergiants: a search for rotationally modulated H\alpha variability
We present the results of a long-term monitoring campaign of the H\alpha line
in a sample of bright OB-supergiants (O7.5-B9) that aims at detecting
rotationally modulated changes potentially related to the existence of
large-scale wind structures. A total of 22 objects were monitor ed during 36
nights spread over 6 months in 2001-2002. Coordinated broad-band photometric
observations were also obtained for some targets. Conspicuous evidence for
variability in H\alpha is found for the stars displaying a feature contaminated
by wind emission. Most changes take place on a daily time-scale, although
hourly variations are also occasionally detected. Convincing evidence for a
cyclical pattern of variability in H\alpha has been found in 2 stars: HD 14134
and HD 42087 (periodic signals are also detected in other stars, but
independent confirmation is required). Rotational modulation is suggested from
the similarity between the observed recurrence time-scales (in the range 13-25
days) and estimated periods of stellar rotation. We call attention to the
atypical case of HD 14134 which exhibits a clear 12.8-d periodicity both in the
photometric and in the spectroscopic data sets. This places this object among a
handful of early-type stars where one may observe a clear link between extended
wind structures and photospheric disturbances. Further modelling may test the
hypothesis that azimuthally-extended wind streams are responsible for the
patterns of spectral variability in our target stars.Comment: 18 pages, accepted for publication in MNRA
ЭФФЕКТИВНОСТЬ ЗОЛЕДРОНОВОЙ КИСЛОТЫ В ПРОФИЛАКТИКЕ КОСТНЫХ МЕТАСТАЗОВ У ПАЦИЕНТОВ С МЕСТНО-РАСПРОСТРАНЕННЫМ РАКОМ ПРЕДСТАТЕЛЬНОЙ ЖЕЛЕЗЫ
The analysis of the performed study has established that zoledronic acid is an effective agent in multimodality therapy for locally advanced prostate cancer (PC) and allows long-term stabilization of bone tissue. In addition, there is evidence for the efficacy of zoledronic acid in preventing bone metastases (BM) and increasing the time to the first BM. The currently accumulated experience with zoledronic acid used in PC permits one to consider its use as standard concomitant therapy.На основании анализа проведенного исследования установлено, что золедроновая кислота является эффективным препаратом в комплексной терапии местно-распространенного рака предстательной железы (РПЖ) и позволяет стабилизировать в течение длительного времени состояние костной ткани. Кроме того, подтверждена эффективность золедроновой кислоты в профилактике костных метастазов (КМ), а также в увеличении времени до появления первого КМ. Накопленный к настоящему времени опыт использования золедроновой кислоты при РПЖ позволяет рассматривать ее назначение как стандартную сопроводительную терапию
Determination of the neutron fluence, the beam characteristics and the backgrounds at the CERN-PS TOF facility
EFFICACY OF ZOLEDRONIC ACID IN THE PREVENTION OF BONE METASTASES IN PATIENTS WITH LOCALLY ADVANCED PROSTATE CANCER
The analysis of the performed study has established that zoledronic acid is an effective agent in multimodality therapy for locally advanced prostate cancer (PC) and allows long-term stabilization of bone tissue. In addition, there is evidence for the efficacy of zoledronic acid in preventing bone metastases (BM) and increasing the time to the first BM. The currently accumulated experience with zoledronic acid used in PC permits one to consider its use as standard concomitant therapy
EFFICACY OF ZOLEDRONIC ACID IN THE PREVENTION OF BONE METASTASES IN PATIENTS WITH LOCALLY ADVANCED PROSTATE CANCER
<p>The analysis of the performed study has established that zoledronic acid is an effective agent in multimodality therapy for locally advanced prostate cancer (PC) and allows long-term stabilization of bone tissue. In addition, there is evidence for the efficacy of zoledronic acid in preventing bone metastases (BM) and increasing the time to the first BM. The currently accumulated experience with zoledronic acid used in PC permits one to consider its use as standard concomitant therapy.</p