34 research outputs found
A SAURON view of galaxies
We have measured the two-dimensional kinematics and line-strength
distributions of 72 representative nearby early-type galaxies, out to
approximately one effective radius, with our panoramic integral-field
spectrograph SAURON. The resulting maps reveal a rich variety in kinematical
structures and linestrength distributions, indicating that early-type galaxies
are more complex systems than often assumed. We are building detailed dynamical
models for these galaxies, to derive their intrinsic shape and dynamical
structure, and to determine the mass of the supermassive central black hole.
Here we focus on two examples, the compact elliptical M32 and the E3 galaxy
NGC4365. These objects represent two extreme cases: M32 has very regular
kinematics which can be represented accurately by an axisymmetric model in
which all stars rotate around the short axis, while NGC4365 is a triaxial
galaxy with a prominent kinematically decoupled core, with an inner core that
rotates about an axis that is nearly perpendicular to the rotation axis of the
main body of the galaxy. Our dynamical models for these objects demonstrate
that two-dimensional observations are essential for deriving the intrinsic
orbital structure and dark matter content of galaxies.Comment: 7 pages (3 figures, full resolution Fig. 1 available at
http://www.strw.leidenuniv.nl/~verolme/M32.ps). Contributed talk to the
Athens Workshop on Galaxies and Chaos, Theory and Observations; Proceedings
to appear in "Galaxies and Chaos", eds. G. Contopoulos and N. Vogli
Dynamical Modeling of SAURON Galaxies
We describe our program for the dynamical modeling of early-type galaxies
observed with the panoramic integral-field spectrograph SAURON. We are using
Schwarzschild's numerical orbit superposition method to reproduce in detail all
kinematical and photometric observables, and recover the intrinsic orbital
structure of the galaxies. Since catastrophes are the most prominent features
in the orbital observables, two-dimensional kinematical coverage is essential
to constrain the dynamical models.Comment: 5 pages, 4 figures, LaTeX. Published in 2003, Carnegie Observatories
Astrophysics Series, Vol. 1: Coevolution of Black Holes and Galaxies, ed. L.
C. Ho (Pasadena: Carnegie Observatories,
http://www.ociw.edu/ociw/symposia/series/symposium1/proceedings.html
A Log-Quadratic Relation Between the Nuclear Black-Hole Masses and Velocity Dispersions of Galaxies
We demonstrate that a log-linear relation does not provide an adequate
description of the correlation between the masses of Super-Massive Black-Holes
(SMBH, M_bh) and the velocity dispersions of their host spheroid (sigma). An
unknown relation between log(M_bh) and log(sigma) may be expanded to second
order to obtain a log-quadratic relation of the form log(M_bh)=alpha+beta
log(sigma/200) + beta_2[log(sigma/200)]^2. We perform a Bayesian analysis using
the Nuker sample, and solve for beta, beta_2 and alpha, in addition to the
intrinsic scatter (delta). We find unbiased parameter estimates of
beta=4.2+/-0.37, beta_2=1.6+/-1.3 and delta=0.275+/-0.05. At the 80% level the
M_bh-sigma relation does not follow a uniform power-law. Indeed, over the
velocity range 70km/s<sigma<380km/s the logarithmic slope of the best fit
relation varies between 2.7 and 5.1, which should be compared with a power-law
estimate of 4.02+/-0.33. Assuming no systematic offset, single epoch virial
SMBH masses estimated for AGN follow the same log-quadratic M_bh-sigma relation
as the Nuker sample, but extend it downward in mass by an order of magnitude.
The log-quadratic term in the M_bh-sigma relation has a significant effect on
estimates of the local SMBH mass function at M_bh>10^9 solar masses, leading to
densities of SMBHs with M_bh>10^10 solar masses that are several orders of
magnitude larger than inferred from a log-linear relation. We also estimate
unbiased parameters for the SMBH-bulge mass relation. With a parameterisation
log(M_bh)=alpha_b + beta_b log(M_b/10^{11}) + beta_2b[log(M_b/10^{11})]^2, we
find beta_b=1.15+/-0.18 and beta_2b=0.12+/-0.14. We determined an intrinsic
scatter delta_b=0.41+/-0.07 which is ~50% larger than the scatter in the
M_bh-sigma relation.Comment: 21 pages, 14 figures. Replaced to correct errors in published versio
Внутриартериальная химиотерапия в комбинированном лечении резектабельного рака желудка с метастазами в печень
В Донецком областном противоопухолевом центре разработан и внедрен способ катетеризации печеночной артерии при паллиативных операциях у больных раком желудка с метастазами в печень. По данному способу пролечено 56 больных резектабельным раком желудка с метастатическим поражением печени, что позволило увеличить продолжительность и улучшить качество жизни больных.У Донецькому обласному протипухлинному центрі розроблено та впроваджено спосіб катетеризації печінкової артерії при паліативних операціях у хворих на рак шлунку з метастазами в печінку. За цим способом проліковано 56 хворих на резектабельний рак шлунку з метастатичним ураженням печінки, що дало змогу збільшити тривалість і поліпшити якість життя хворих.A method of catheterization of hepatic artery at palliative surgery in patients with gastric cancer and metastases to the liver was worked out and introduced at Donetsk Regional Antitumor Center. This method was used in 56 patients with operable cancer of the stomach with metastases to the liver, which allowed increasing the duration and improving the quality of life of the patients
Repeated nipple fluid aspiration
Background: Despite intensive surveillance, a high rate of interval malignancies is still seen in women at increased breast cancer risk. Therefore, novel screening modalities aiming at early detection remain needed. The intraductal approach offers the possibility to directly sample fluid containing cells, DNA and proteins from the mammary ductal system where, in the majority of cases, breast cancer originates. Fluid from the breast can non-invasively be obtained by oxytocin-assisted vacuum aspiration, called nipple fluid aspiration (NFA). The goal of this feasibility study was to evaluate the potential of repeated NFA, which is a critical and essential step to evaluate its possible value as a breast cancer screening method. Methods: In this multicenter, prospective study, we annually collected nipple fluid for up to 5 consecutive years from women at increased breast cancer risk, and performed a questionnaire-based survey regarding discomfort of the aspiration. Endpoints of the current interim analyses were the feasibility and results of 994 NFA procedures in 451 women with total follow-up of 560 person years of observation. Results: In this large group of women at increased risk of breast cancer, repetitive NFA appeared to be feasible and safe. In 66.4% of aspirated breasts, nipple fluid was successfully obtained. Independent predictive factors for successful NFA were premenopausal status, spontaneous nipple discharge, smaller breast size, bilateral oophorectomy and previous use of hormone replacement therapy or anti-hormonal treatment. The procedure was well tolerated with low discomfort. Drop-out rate was 20%, which was mainly due to repeated unsuccessful aspiration attempts. Only 1.6% of women prematurely declined further participation because of side effects. Conclusions: Repeated NFA in women at increased breast cancer risk is feasible and safe. Therefore, NFA is a promising method to non-invasively obtain a valuable source of potential breast cancer specific biomarkers
Supermassive Black Holes in Galactic Nuclei: Past, Present and Future Research
This review discusses the current status of supermassive black hole research,
as seen from a purely observational standpoint. Since the early '90s, rapid
technological advances, most notably the launch of the Hubble Space Telescope,
the commissioning of the VLBA and improvements in near-infrared speckle imaging
techniques, have not only given us incontrovertible proof of the existence of
supermassive black holes, but have unveiled fundamental connections between the
mass of the central singularity and the global properties of the host galaxy.
It is thanks to these observations that we are now, for the first time, in a
position to understand the origin, evolution and cosmic relevance of these
fascinating objects.Comment: Invited Review, 114 pages. Because of space requirements, this
version contains low resolution figures. The full resolution version can be
downloaded from http://www.physics.rutgers.edu/~lff/publications.htm
SAURON: Observations of E/S0/Sa galaxies
We present results from a new and unique integral-field spectrograph, SAURON.
It has a large field of view and high throughput and is primarily built for the
study of stellar & gaseous kinematics and stellar populations in galaxies. Its
aim is to carry out a systematic survey of the velocity fields, velocity
dispersions, and line-strength distributions of nearby ellipticals, lenticular
galaxies and spiral bulges. Its wide field is especially useful for the study
of complicated velocity structures. Together with other spectroscopic data,
images, and dynamical modelling, SAURON will help to constrain the intrinsic
shapes, mass-to-light ratios, and stellar populations of early-type galaxies
and spiral bulges.Comment: 1 page, 1 figure, to appear in Revista Mexicana de Astrofisica y
Astronomia Conf. Serie
Consistency of the black hole mass determination in AGN from the reverberation and the X-ray excess variance method
Values of black hole masses are frequently determined with the help of the
reverberation method. This method requires a specific geometrical factor
related to the distribution of the orbits of the Broad Line Region clouds.
Onken et al. determined the value f^2= 1.37+/-0.45 from the black hole mass -
dispersion relation. In this paper we determine this factor using an
independent mass determination from the X-ray variance method for a number of
Seyfert 1 galaxies and comparing them with the reverberation results by
Peterson et al. We obtain mean value f^2 = 1.12 +/- 0.54, consistent with Onken
et al. Both values are larger than the value 0.75 corresponding to a spherical
geometry. It indicates that most probably all values of the black hole masses
obtained with the use of the Kaspi et al. formulae should be multiplied by a
factor of \sim 1.7. This also shows that the Broad Line Region is rather flat,
and hints for a dependence of the factor f^2 on a source inclination seem to be
present in the data.Comment: 7 pages, 4 figures, 1 table; accepted for publication in MNRA
