1,296 research outputs found
SIPS - Screening-Instrument für prämenstruelle Symptome*: Die deutsche Version des Premenstrual Symptoms Screening Tool zur Erfassung klinisch relevanter Beschwerden
Zusammenfassung: Hintergrund: Prämenstruelle dysphorische Störungen (PMDS) und schwere prämenstruelle Syndrome (PMS) treten häufig auf, bleiben jedoch oft unerkannt und unbehandelt. Begünstigt wird dies durch das Fehlen eines entsprechenden deutschsprachigen Screening-Instruments. Ziel dieser Studie war es, das englischsprachige Premenstrual Symptoms Screening Tool (PSST) ins Deutsche zu übertragen und seine Anwendung zu prüfen. Material und Methoden: Die deutschsprachige Version des PSST wurde als "Screening-Instrument für prämenstruelle Symptome" (SIPS) erstellt und ihre Güte an 47 Frauen mit und ohne PMDS/schwerem PMS internetbasiert mittels täglichen Symptomeinschätzungen bestimmt. Ergebnisse: Die Retest-Reliabilität des SIPS betrug r=0,69, das Cronbachsα 0,924. Als Validitätsmaß des SIPS zeigten sich signifikante Unterschiede zwischen Frauen mit und ohne PMDS/schwerem PMS, bestimmt durch das SIPS, bezüglich prospektiv erfasster prämenstrueller Symptomatik (F[2,44]=4,52, p<0,001) und Symptomveränderung (F[2,44]=25,23, p<0,001). Schlussfolgerung: Das SIPS ist reliabel und valide und kann helfen, Frauen mit behandlungsbedürftigen prämenstruellen Beschwerden zu identifiziere
SIPS - Screening-Instrument für prämenstruelle Symptome : Die deutsche Version des Premenstrual Symptoms Screening Tool zur Erfassung klinisch relevanter Beschwerden
Premenstrual Dysphoric Disorder (PMDD) and severe Premenstrual Syndrome (PMS) are common, yet often remain unrecognized and not adequately treated. One reason for this is the lack of a valid German screening instrument. The aim of the present study was to create a German version of the English "premenstrual symptoms screening tool (PSST)" and to verify its applicability. The German version of the PSST was created as "Screening- Instrument für Prämenstruelle Symptome (SIPS)" and its reliability and validity estimated based on data from 47 women with and without PMDD/severe PMS, using internet-based daily symptom-ratings. The retest-reliability of the SIPS was r=0.69, Cronbach`s Alpha was 0.924. As indicator of the convergent validity of the SIPS, there were significant differences between women with and without PMDD/severe PMS as identified by the SIPS, with regard to prospectively assessed premenstrual symptomatology (F(2,44)=4.52, p>0.001) and symptom change (F(2,44)=25.23, p>0.001). The SIPS is reliable and valid and may help improving the identification of women who require treatment for their premenstrual symptoms
Nucleate pool boiling in the long duration low gravity environment of the Space Shuttle
The results are presented of an experimental study of nucleate pool boiling performed in the low gravity environment of the space shuttle. Photographic observations of pool boiling in Freon 113 were obtained during the 'Tank Pressure Control Experiment,' flown on the Space Transportation System, STS-43 in August 1991. Nucleate boiling data from large (relative to bubble size) flat heating surfaces (0.1046 by 0.0742 m) was obtained at very low heat fluxes (0.22 to 1.19 kW/sq m). The system pressure and the bulk liquid subcooling varied in the range of 40 to 60 kPa and 3 to 5 C respectively. Thirty-eight boiling tests, each of 10-min duration for a given heat flux, were conducted. Measurements included the heater power, heater surface temperature, the liquid temperature and the system pressure as functions of heating time. Video data of the first 2 min of heating was recorded for each test. In some tests the video clearly shows the inception of boiling and the growth and departure of bubbles from the surface during the first 2 min of heating. In the absence of video data, the heater temperature variation during heating shows the inception of boiling and stable nucleate boiling. During the stable nucleate boiling, the wall superheat varied between 2.8 to 3.8 C for heat fluxes in the range of 0.95 to 1.19 kW/sq m. The wall superheat at the inception of boiling varied between 2 to 13 C
Systematic Uncertainties in Black Hole Masses Determined from Single Epoch Spectra
We explore the nature of systematic errors that can arise in measurement of
black hole masses from single-epoch spectra of active galactic nuclei (AGNs) by
utilizing the many epochs available for NGC 5548 and PG1229+204 from
reverberation mapping databases. In particular, we examine systematics due to
AGN variability, contamination due to constant spectral components (i.e.,
narrow lines and host galaxy flux), data quality (i.e., signal-to-noise ratio,
S/N), and blending of spectral features by comparing the precision and accuracy
of single-epoch mass measurements to those of recent reverberation mapping
studies. We calculate masses by characterizing the broad Hbeta emission line by
both the full width at half maximum and the line dispersion and demonstrate the
importance of removing narrow emission-line components and host starlight. We
find that the reliability of line width measurements rapidly decreases for S/N
lower than ~10 to 20 (per pixel) and that fitting the line profiles instead of
direct measurement of the data does not mitigate this problem but can, in fact,
introduce systematic errors. We also conclude that a full spectral
decomposition to deblend the AGN and galaxy spectral features is unnecessary
except to judge the contribution of the host galaxy to the luminosity and to
deblend any emission lines that may inhibit accurate line width measurements.
Finally, we present an error budget which summarizes the minimum observable
uncertainties as well as the amount of additional scatter and/or systematic
offset that can be expected from the individual sources of error investigated.
In particular, we find that the minimum observable uncertainty in single-epoch
mass estimates due to variability is ~ 20 per pixel)
spectra.Comment: 60 pages, 20 figures, accepted for publication in Ap
Reverberation Mapping Results from MDM Observatory
We present results from a multi-month reverberation mapping campaign
undertaken primarily at MDM Observatory with supporting observations from
around the world. We measure broad line region (BLR) radii and black hole
masses for six objects. A velocity-resolved analysis of the H_beta response
shows the presence of diverse kinematic signatures in the BLR.Comment: To appear in the Proceedings of the IAU Symposium No. 267:
Co-Evolution of Central Black Holes and Galaxies, Rio de Janeiro, 200
The Lick AGN Monitoring Project: Broad-Line Region Radii and Black Hole Masses from Reverberation Mapping of Hbeta
We have recently completed a 64-night spectroscopic monitoring campaign at
the Lick Observatory 3-m Shane telescope with the aim of measuring the masses
of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected
masses in the range ~10^6-10^7 M_sun and also the well-studied nearby active
galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including
NGC 5548) showed optical variability of sufficient strength during the
monitoring campaign to allow for a time lag to be measured between the
continuum fluctuations and the response to these fluctuations in the broad
Hbeta emission. We present here the light curves for the objects in this sample
and the subsequent Hbeta time lags for the nine objects where these
measurements were possible. The Hbeta lag time is directly related to the size
of the broad-line region, and by combining the lag time with the measured width
of the Hbeta emission line in the variable part of the spectrum, we determine
the virial mass of the central supermassive black hole in these nine AGNs. The
absolute calibration of the black hole masses is based on the normalization
derived by Onken et al. We also examine the time lag response as a function of
velocity across the Hbeta line profile for six of the AGNs. The analysis of
four leads to ambiguous results with relatively flat time lags as a function of
velocity. However, SBS 1116+583A exhibits a symmetric time lag response around
the line center reminiscent of simple models for circularly orbiting broad-line
region (BLR) clouds, and Arp 151 shows an asymmetric profile that is most
easily explained by a simple gravitational infall model. Further investigation
will be necessary to fully understand the constraints placed on physical models
of the BLR by the velocity-resolved response in these objects.Comment: 24 pages, 16 figures and 13 tables, submitted to Ap
A Revised Broad-Line Region Radius and Black Hole Mass for the Narrow-Line Seyfert 1 NGC 4051
We present the first results from a high sampling rate, multi-month
reverberation mapping campaign undertaken primarily at MDM Observatory with
supporting observations from telescopes around the world. The primary goal of
this campaign was to obtain either new or improved Hbeta reverberation lag
measurements for several relatively low luminosity AGNs. We feature results for
NGC 4051 here because, until now, this object has been a significant outlier
from AGN scaling relationships, e.g., it was previously a ~2-3sigma outlier on
the relationship between the broad-line region (BLR) radius and the optical
continuum luminosity - the R_BLR-L relationship. Our new measurements of the
lag time between variations in the continuum and Hbeta emission line made from
spectroscopic monitoring of NGC 4051 lead to a measured BLR radius of R_BLR =
1.87 (+0.54 -0.50) light days and black hole mass of M_BH = 1.73 (+0.55 -0.52)
x 10^6 M_sun. This radius is consistent with that expected from the R_BLR-L
relationship, based on the present luminosity of NGC 4051 and the most current
calibration of the relation by Bentz et al. (2009a). We also present a
preliminary look at velocity-resolved Hbeta light curves and time delay
measurements, although we are unable to reconstruct an unambiguous
velocity-resolved reverberation signal.Comment: 38 pages, 7 figures, accepted for publication in ApJ, changes from v1
reflect suggestions from anonymous refere
The Lick AGN Monitoring Project: Reverberation Mapping of Optical Hydrogen and Helium Recombination Lines
We have recently completed a 64-night spectroscopic monitoring campaign at
the Lick Observatory 3-m Shane telescope with the aim of measuring the masses
of the black holes in 12 nearby (z < 0.05) Seyfert 1 galaxies with expected
masses in the range ~10^6-10^7M_sun and also the well-studied nearby active
galactic nucleus (AGN) NGC 5548. Nine of the objects in the sample (including
NGC 5548) showed optical variability of sufficient strength during the
monitoring campaign to allow for a time lag to be measured between the
continuum fluctuations and the response to these fluctuations in the broad
Hbeta emission, which we have previously reported. We present here the light
curves for the Halpha, Hgamma, HeII 4686, and HeI 5876 emission lines and the
time lags for the emission-line responses relative to changes in the continuum
flux. Combining each emission-line time lag with the measured width of the line
in the variable part of the spectrum, we determine a virial mass of the central
supermassive black hole from several independent emission lines. We find that
the masses are generally consistent within the uncertainties. The time-lag
response as a function of velocity across the Balmer line profiles is examined
for six of the AGNs. Finally we compare several trends seen in the dataset
against the predictions from photoionization calculations as presented by
Korista & Goad. We confirm several of their predictions, including an increase
in responsivity and a decrease in the mean time lag as the excitation and
ionization level for the species increases. Further confirmation of
photoionization predictions for broad-line gas behavior will require additional
monitoring programs for these AGNs while they are in different luminosity
states. [abridged]Comment: 37 pages, 18 figures and 15 tables, accepted for publication in the
Astrophysical Journa
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