77 research outputs found
Luminosities and infrared excess in Type II and anomalous Cepheids in the Large and Small Magellanic Clouds
(abridged) Type II and anomalous Cepheids (ACs) are useful distance
indicators when there are too few classical Cepheids or when RR Lyrae stars are
too faint. We study the sample of 335 Type II and ACs in the Small and Large
MCls detected in OGLE-III data.The SEDs are constructed and fitted with a dust
radiative transfer model, thereby leading to a determination of luminosity and
effective temperature.In addition, a subsample of targets is investigated for
possible binarity by looking for the light-time travel effect (LITE).
Hertzsprung-Russell diagrams (HRD) are constructed and compared to evolutionary
tracks and theoretical instability strips (ISs). In agreement with previous
suggestions, the BL Her subclass can be explained by the evolution of
0.5-0.6~\msol\ stars evolving off the ZAHB and the ACs can be explained
by the evolution of 1.1-2.3~\msol\ stars. The evolution of the W Vir
subclass is not clear. A relation to binarity might be at the origin of the W
Vir stars, which has already been explicitly suggested for the peculiar W Vir
stars. For of the RV Tau and of the W Vir objects an
infrared excess is detected from the SED fitting. A recent result is confirmed
that stars exist with luminosities below that predicted from single-star
evolution, which show a clear infrared excess, and the shape of the excess
suggests a connection to binary evolution. The investigation of the LITE effect
revealed 20 systems that appear to show periodic variations and may be new
binaries, although this study requires follow-up. About 40 stars show
significant period changes.Comment: A&A accepte
The period-luminosity and period-radius relations of Type II and anomalous Cepheids
Method: In an accompanying paper (arXiv: 1705.00886) we determined luminosity
and effective temperature for the 335 T2Cs and ACs in the LMC and SMC
discovered in the OGLE-III survey, by constructing the spectral energy
distribution (SED) and fitting this with model atmospheres and a dust radiative
transfer model (in the case of dust excess). Building on these results we study
the PL and PR relations.
Using existing pulsation models for RR Lyrae and classical Cepheids we derive
the period-luminosity-mass-temperature-metallicity relations, and then estimate
the pulsation mass.
Results: The PL relation for the T2Cs does not appear to depend on
metallicity, and, excluding the dusty RV Tau stars, is (for days). Relations for fundamental and first overtone
LMC ACs are also presented. The PR relation for T2C also shows little or no
dependence on metallicity or period. Our preferred relation combines SMC and
LMC stars and all T2C subclasses, and is .
Relations for fundamental and first overtone LMC ACs are also presented. The
pulsation masses from the RR Lyrae and classical Cepheid pulsation models agree
well for the short period T2Cs, the BL Her subtype, and ACs, and are consistent
with estimates in the literature, i.e. \msol\ and
\msol, respectively. The masses of the W Vir appear
similar to the BL Her. The situation for the pWVir and RV Tau stars is less
clear. For many RV Tau the masses are in conflict with the standard picture of
(single-star) post-AGB evolution, the masses being either too large (
1 \msol) or too small ( 0.4 \msol).Comment: A&A accepte
Premiumerwerb internationaler Investoren für Immobilien in deutschen Städten
Umfangreiche internationale Transaktionen am Investmentmarkt für Immobilien des letzten Jahrzehnts werfen die grundlegende Frage auf, ob sich diese von nationalen unterscheiden. Als methodische Entwicklung soll mittels Propensity Score-Matching der Einfluss von verschiedenen Transaktions-charakteristika in den Stichproben begrenzt werden, die nicht mit den von ausländischen Investoren gekauften und verkauften Transaktionen vergleichbar sind, sodass das Problem der Selektionsverzerrung gelöst wird.
Für eine deutsche Stichprobe mit Daten zu knapp 2.400 gewerblichen Immobilientransaktionen von Büroimmobilien in den sieben A-Lagen werden in der ersten Studie sowohl Auswirkungen auf Kauf- als auch auf Verkaufspreise analysiert. Dabei wird aufgezeigt, dass internationale Investoren im Vergleich zu ähnlichen Immobilien, die von nationalen Investoren gekauft und verkauft werden, mit einem signifikanten Abschlag von ca. 14,7% verkaufen, während ein signifikanter Preisaufschlag internationaler Käufer dann realisiert wird, wenn auf der Verkäuferseite ein nationaler Investor vertreten ist. Dabei beträgt das gezahlte Premium ca. 13,1%. Nationale Verkäufer erzielen damit bessere Preise, wenn auf der Käuferseite ein internationaler Investor vertreten ist.
Die zweite Studie zeigt, dass ein Premium von ausländischen Investoren in Höhe von ca. 22,4% beim Ankauf gezahlt wird. Darüber hinaus kann durch Tests auf Asymmetrie aufgezeigt werden, dass ausländische Investoren ein höheres Premium von ca. 30,3% zahlen, wenn auf der Verkäuferseite inländische Investoren vertreten sind. Weiterführende Analysen auf nicht gemessene Qualitätsmerkmale zeigen, dass es unbeobachtete und positive, preisliche Eigenschaften bei ausländischen Transaktionen gibt.
In der dritten Studie wird aufgezeigt, dass internationale Investoren im Vergleich zu ähnlichen Immobilien, die von nationalen Investoren gekauft und verkauft werden, mit einem signifikanten Premium von ca. 31% kaufen. Das Premium ist nahezu identisch mit ca. 30%, wenn auf der Verkaufsseite ein nationaler Investor vertreten ist. Weiterführende Tests auf nicht gemessene Qualitätsmerkmale deuten darauf hin, dass es unbeobachtete preisliche Eigenschaften im Zusammenhang mit ausländischen Transaktionen gibt, wo sowohl Käufer als auch Verkäufer ausländischer Herkunft sind
Type II and anomalous Cepheids in the Kepler K2 mission
We present the results of the analysis of Type II and anomalous Cepheids
using the data from the Kepler K2 mission. The precise light curves of these
pulsating variable stars are the key to study the details of their pulsation,
such as the period-doubling effect or the presence of additional modes. We
applied the Automated Extended Aperture Photometry (autoEAP) to obtain the
light curves of the targeted variable stars which were observed. The light
curves were Fourier analyzed. We investigated twelve stars observed by the K2
mission, seven Type II and five anomalous Cepheids. Among the Type II Cepheids
EPIC 210622262 shows period-doubling, and four stars have modulation present in
their light curves which are different from the period-doubling effect. We
calculated the high-order Fourier parameters for the short-period Cepheids. We
also determined physical parameters by fitting model atmospheres to the
spectral energy distributions. The determined distances using the parallaxes
measured by the Gaia space telescope have limited precision below 16 mag for
these types of pulsating stars, regardless if the inverse method is used or the
statistical method to calculate the distances. The BaSTI evolutionary models
were compared to the luminosities and effective temperatures. Most of the Type
II Cepheids are modeled with low metallicity models, but for a few of them
solar-like metallicity ([Fe/H]=0.06) model is required. The anomalous Cepheids
are compared to low-metallicity single stellar models. We do not see signs of
binarity among our sample stars.Comment: 21 pages, 13 figures, accepted for publication in MNRA
Performance of the WID-qEC test versus sonography to detect uterine cancers in women with abnormal uterine bleeding (EPI-SURE): a prospective, consecutive observational cohort study in the UK
BACKGROUND: To detect uterine cancer, simpler and more specific index tests are needed to triage women with abnormal uterine bleeding to a reference histology test. We aimed to compare the performance of conventional index imaging tests with the novel WID-qEC DNA methylation test in terms of detecting the presence or absence of uterine cancers in women with abnormal uterine bleeding. METHODS: EPI-SURE was a prospective, observational study that invited all women aged 45 years and older with abnormal uterine bleeding attending a tertiary gynaecological diagnostic referral centre at University College London Hospital (London, UK) to participate. Women meeting these inclusion criteria who consented to participate were included. Pregnant women and those with previous hysterectomy were excluded. A cervicovaginal sample for the WID-qEC test was obtained before standard assessment using index imaging tests (ie, ultrasound) and, where applicable, reference histology (ie, biopsy, hysteroscopy, or both) was performed. Technicians performing the WID-qEC test were masked to the final clinical outcome. The result of the WID-qEC test is defined as the sum of the percentage of fully methylated reference (ΣPMR) of the ZSCAN12 and GYPC regions. Patients were followed until diagnostic resolution or until June 12, 2023. The primary outcome was to assess the real-world performance of the WID-qEC test in comparison with ultrasound with regard to the area under the receiver-operating-characteristic curve (AUC), sensitivity, specificity, and positive and negative predictive values. EPI-SURE is registered with ISRCTN (16815568). FINDINGS: From June 1, 2022, to Nov 24, 2022, 474 women were deemed eligible to participate. 74 did not accept the invitation to participate, and one woman withdrew after providing consent. 399 women were included in the primary analysis cohort. Based on 603 index imaging tests, 186 (47%) women were recommended for a reference histology test (ie, biopsy, hysteroscopy, or both). 12 women were diagnosed with cancer, 375 were not diagnosed with cancer, and 12 had inconclusive clinical outcomes and were considered study dropouts. 198 reference histology test procedures detected nine cases of cancer and missed two; one further cancer was directly diagnosed at hysterectomy without a previous reference test. The AUC for detection of uterine cancer based on endometrial thickness in mm was 87·2% (95% CI 71·1-100·0) versus 94·3% (84·7-100·0) based on WID-qEC (p=0·48). Endometrial thickness assessment on ultrasound scan was possible in 379 (95%) of the 399 women and a prespecified cut-off of 4·5 mm or more showed a sensitivity of 90·9% (95% CI 62·3-98·4), a specificity of 79·1% (74·5-82·9), a positive predictive value of 11·8% (6·5-20·3), and a negative predictive value of 99·6% (98·0-99·9). The WID-qEC test was possible in 390 (98%) of the 399 patients with a sensitivity of 90·9% (95% CI 62·3-98·4), a specificity of 92·1% (88·9-94·4), a positive predictive value of 25·6% (14·6-41·1), and a negative predictive value of 99·7% (98·3-99·9), when the prespecified threshold of 0·03 ΣPMR or more was applied. When a higher threshold (≥0·3 ΣPMR) was applied the specificity increased to 97·3% (95% CI 95·1-98·5) without a change in sensitivity. INTERPRETATION: The WID-qEC test delivers fast results and shows improved performance compared with a combination of imaging index tests. Triage of women with abnormal uterine bleeding using the WID-qEC test could reduce the number of women requiring histological assessments for identification of potential malignancy and specifically reduce the false positive rate. FUNDING: The Eve Appeal, Land Tirol, and the European Research Council under the European Union's Horizon 2020 Research and Innovation Programme
Study of exclusive one-pion and one-eta production using hadron and dielectron channels in pp reactions at kinetic beam energies of 1.25 GeV and 2.2 GeV with HADES
We present measurements of exclusive ensuremathπ+,0 and η production in pp reactions at 1.25GeV and 2.2GeV beam kinetic energy in hadron and dielectron channels. In the case of π+ and π0 , high-statistics invariant-mass and angular distributions are obtained within the HADES acceptance as well as acceptance-corrected distributions, which are compared to a resonance model. The sensitivity of the data to the yield and production angular distribution of Δ (1232) and higher-lying baryon resonances is shown, and an improved parameterization is proposed. The extracted cross-sections are of special interest in the case of pp → pp η , since controversial data exist at 2.0GeV; we find \ensuremathσ=0.142±0.022 mb. Using the dielectron channels, the π0 and η Dalitz decay signals are reconstructed with yields fully consistent with the hadronic channels. The electron invariant masses and acceptance-corrected helicity angle distributions are found in good agreement with model predictions
A Simple Cervicovaginal Epigenetic Test for Screening and Rapid Triage of Women With Suspected Endometrial Cancer: Validation in Several Cohort and Case/Control Sets
PURPOSEEndometrial cancer (EC) incidence has been rising over the past 10 years. Delays in diagnosis reduce survival and necessitate more aggressive treatment. We aimed to develop and validate a simple, noninvasive, and reliable triage test for EC to reduce the number of invasive diagnostic procedures and improve patient survival.METHODSWe developed a test to screen and triage women with suspected EC using 726 cervical smear samples from women with and without EC, and validated the test in 562 cervicovaginal samples using three different collection methods (cervical smear: n = 248; vaginal swab: n = 63; and self-collection: n = 251) and four different settings (case/control: n = 388; cohort of women presenting with postmenopausal bleeding: n = 63; a cohort of high-risk women with Lynch syndrome: n = 25; and a nested case/control setting from a screening cohort and samples taken up to 3 years before EC diagnosis: n = 86).RESULTSWe describe the Women's cancer risk IDentification - quantitative polymerase chain reaction test for Endometrial Cancer (WID-qEC), a three-marker test that evaluates DNA methylation in gene regions of GYPC and ZSCAN12. In cervical, self-collected, and vaginal swab samples derived from symptomatic patients, it detected EC with sensitivities of 97.2% (95% CI, 90.2 to 99.7), 90.1% (83.6 to 94.6), and 100% (63.1 to 100), respectively, and specificities of 75.8% (63.6 to 85.5), 86.7% (79.3 to 92.2), and 89.1% (77.8 to 95.9), respectively. The WID-qEC identified 90.9% (95% CI, 70.8 to 98.9) of EC cases in samples predating diagnosis up to 1 year. Test performance was similar across menopausal status, age, stage, grade, ethnicity, and histology.CONCLUSIONThe WID-qEC is a noninvasive reliable test for triage of women with symptoms suggestive of ECs. Because of the potential for self-collection, it could improve early diagnosis and reduce the reliance for in-person visits
Correlação do volume da vesícula vitelínica obtida por meio da ultrassonografia tridimensional com a idade gestacional entre a 7ª e a 10ª semanas usando o método multiplanar
Repercussões da cicatriz uterina resultante de cesariana prévia na dopplervelocimetria das artérias uterinas entre 26 e 32 semanas
Multimessenger Search for Sources of Gravitational Waves and High-Energy Neutrinos: Results for Initial LIGO-Virgo and IceCube
We report the results of a multimessenger search for coincident signals from
the LIGO and Virgo gravitational-wave observatories and the partially completed
IceCube high-energy neutrino detector, including periods of joint operation
between 2007-2010. These include parts of the 2005-2007 run and the 2009-2010
run for LIGO-Virgo, and IceCube's observation periods with 22, 59 and 79
strings. We find no significant coincident events, and use the search results
to derive upper limits on the rate of joint sources for a range of source
emission parameters. For the optimistic assumption of gravitational-wave
emission energy of \,Mc at \,Hz with \,ms duration, and high-energy neutrino emission of \,erg
comparable to the isotropic gamma-ray energy of gamma-ray bursts, we limit the
source rate below \,Mpcyr. We also examine
how combining information from gravitational waves and neutrinos will aid
discovery in the advanced gravitational-wave detector era
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