786 research outputs found
High incidence of Angina pectoris in patients treated with 5-fluorouracil - A planned surveillance study with 102 patients
Objective: Angina pectoris, arrhythmic sudden death and myocardial infarction, all these cardiac events have occasionally been reported during 5-fluorouracil (5-FU) chemotherapy. Underlying mechanisms leading to these events are unknown; damage to the myocytes or vasospasms have been discussed. Methods: 102 consecutive and unselected patients were monitored with 12-lead ECG, echocardiography and radionuclide ventriculography prior to the first cycle of 5-FU chemotherapy and 3 months from baseline. Results: 19% of the patients developed reversible symptoms of angina pectoris during treatment which lasted up to 12 h after cessation of the infusion. Most of the 19 patients showed corresponding ECG changes. 6 out of the 19 patients with severe angina pectoris had subsequent coronary angiography. In none of these patients the coronary angiography showed coronary artery disease, but it showed low ventricular function (ejection fraction <50%) in 2 patients. The ejection fraction did not increase overtime. Arrhythmias were screened for with Holter monitoring during 5-FU chemotherapy. The frequency of bradycardia and ventricular extrasystoles increased significantly (p < 0.05) during treatment compared to arrhythmias in Holter monitoring 3 months later. Furthermore the Qtc time in the ECG 3 months later was significantly prolonged (p < 0.05) compared to baseline values. Conclusions:The incidence of angina pectoris in patients during 5-FU treatment seems higher than previously suspected. As myocardial ischemia can be fatal, attentiveness to these symptoms and immediate treatment are crucial. Copyright (C) 2003 S. Karger AG, Basel
Phonon-Assisted Two-Photon Interference from Remote Quantum Emitters
Photonic quantum technologies are on the verge offinding applications in everyday life with quantum cryptography andquantum simulators on the horizon. Extensive research has beencarried out to identify suitable quantum emitters and single epitaxialquantum dots have emerged as near-optimal sources of bright, on-demand, highly indistinguishable single photons and entangledphoton-pairs. In order to build up quantum networks, it is essentialto interface remote quantum emitters. However, this is still anoutstanding challenge, as the quantum states of dissimilarâartificialatomsâhave to be prepared on-demand with highfidelity and thegenerated photons have to be made indistinguishable in all possibledegrees of freedom. Here, we overcome this major obstacle and show an unprecedented two-photon interference (visibility of 51±5%) from remote strain-tunable GaAs quantum dots emitting on-demand photon-pairs. We achieve this result by exploiting forthefirst time the full potential of a novel phonon-assisted two-photon excitation scheme, which allows for the generation ofhighly indistinguishable (visibility of 71±9%) entangled photon-pairs (fidelity of 90±2%), enables push-button biexciton statepreparation (fidelity of 80±2%) and outperforms conventional resonant two-photon excitation schemes in terms of robustnessagainst environmental decoherence. Our results mark an important milestone for the practical realization of quantum repeatersand complex multiphoton entanglement experiments involving dissimilar artificial atom
Twinning in muskox and the cytogenetic investigation of a freemartin
The occurrence of twinning has been documented for muskox in both wild and captive populations. Of two known captive twin births only one set survived beyond 120 days. In both cases the twins were male-female pairs and both females showed abnormal sexual development. Two sets of stillborn twins have also been recorded. All four stillborn fetuses were female and none showed anomalies of the reproductive tract upon post-mortem examination. Blood cultures from the surviving male and female twins revealed that both were chimeric, indicating the admixture of fetal blood. Fibroblast cultures were normal for the respective sex of each individual. The freemartin heifer had anatomical abnormalities of the clitoris as well as the secondary sex characteristics of a male
A far-UV survey of three hot, metal-polluted white dwarf stars: WD0455-282, WD0621-376, and WD2211-495
Using newly obtained high-resolution data () from the
\textit{Hubble Space Telescope}, and archival UV data from the \textit{Far
Ultraviolet Spectroscopic Explorer} we have conducted a detailed UV survey of
the three hot, metal-polluted white dwarfs WD0455-282, WD0621-376, and
WD2211-495. Using bespoke model atmospheres we measured , log
, and photospheric abundances for these stars. In conjunction with data from
Gaia we measured masses, radii, and gravitational redshift velocities for our
sample of objects. We compared the measured photospheric abundances with those
predicted by radiative levitation theory, and found that the observed Si
abundances in all three white dwarfs, and the observed Fe abundances in
WD0621-376 and WD2211-495, were larger than those predicted by an order of
magnitude. These findings imply not only an external origin for the metals, but
also ongoing accretion, as the metals not supported by radiative levitation
would sink on extremely short timescales. We measured the radial velocities of
several absorption features along the line of sight to the three objects in our
sample, allowing us to determine the velocities of the photospheric and
interstellar components along the line of sight for each star. Interestingly,
we made detections of circumstellar absorption along the line of sight to
WD0455-282 with three velocity components. To our knowledge, this is the first
such detection of multi-component circumstellar absorption along the line of
sight to a white dwarf.Comment: 19 pages, 23 figures, 8 tables. Accepted for publication in the
Monthly Notices of the Royal Astronomical Societ
Multimodal hyperscanning reveals that synchrony of body and mind are distinct in mother-child dyads
Hyperscanning studies have begun to unravel the brain mechanisms underlying social interaction, indicating a functional role for interpersonal neural synchronization (INS), yet the mechanisms that drive INS are poorly understood. The current study, thus, addresses whether INS is functionally-distinct from synchrony in other systems â specifically the autonomic nervous system and motor behavior. To test this, we used concurrent functional near-infrared spectroscopy - electrocardiography recordings, while NâŻ=âŻ34 mother-child and stranger-child dyads engaged in cooperative and competitive tasks. Only in the neural domain was a higher synchrony for mother-child compared to stranger-child dyads observed. Further, autonomic nervous system and neural synchrony were positively related during competition but not during cooperation. These results suggest that synchrony in different behavioral and biological systems may reflect distinct processes. Furthermore, they show that increased mother-child INS is unlikely to be explained solely by shared arousal and behavioral similarities, supporting recent theories that postulate that INS is higher in close relationships
Reddening, Absorption, and Decline Rate Corrections for a Complete Sample of Type Ia Supernovae leading to a Fully Corrected Hubble Diagram to v<30,000kms-1
Photometric BVI and redshift data corrected for streaming motions are
compiled for 111 "Branch normal", 4 1991T-like, 7 1991bg-like, and 2 unusual
SNe Ia. Color excesses E(B-V)host of normal SNe Ia, due to the absorption of
the host galaxy, are derived by three independent methods leading to the
intrinsic colors at maximum of (B-V)00=-0.024, and (V-I)00=-0.265 if normalized
to a common decline rate of Dm_15=1.1. The strong correlation between redshift
absolute magnitudes (based on Ho=60), corrected only for the extrinsic Galactic
absorption, and the derived E(B-V)host leads to well determined, yet abnormal
absorption-to-reddening ratios of R_BVI=3.65, 2.65, and 1.35. Comparison with
the canonical Galactic values of 4.1, 3.1, 1.8 forces the conclusion that the
law of interstellar absorption in the path length to the SN in the host galaxy
is different from the local Galactic law. Improved correlations of the fully
corrected absolute magnitudes with host galaxy type, decline rate, and
intrinsic color are derived. The four peculiar 1991T-type SNe are significantly
overluminous as compared to Branch-normal SNe Ia. The overluminosity of the
seven 1999aa-like SNe is less pronounced. The seven 1991bg-types in the sample
constitute a separate class of SNeIa, averaging in B two magnitudes fainter
than the normal Ia. New Hubble diagrams in BVI are derived out to ~30,000kms-1
using the fully corrected magnitudes and velocities, corrected for streaming
motions. Nine solutions for the intercept magnitudes in these diagrams show
extreme stability at the 0.04 level using various subsamples of the data. The
same precepts for fully correcting SN magnitudes we shall use for the
luminosity recalibration of SNe Ia in the forthcoming final review of our HST
Cepheid-SN experiment for the Hubble constant.Comment: 49 pages, 15 figures, 8 tables, accepted for publication in the
Astrophysical Journa
Wireless wake-up sensor network for structural health monitoring of large-scale highway bridges
To realize in-situ structural health monitoring of critical infrastructure such as bridges, we present a powerful, but also low power and flexible, wireless sensor node utilizing a wake-up transceiver. The sensor node is equipped with several kinds of sensors, such as temperature, pressure and acceleration for in-situ monitoring of critical infrastructure. In addition to these commonly used sensors in wireless sensor networks, some nodes are equipped with global navigation satellite system receivers (GNSS) and others with tilt and acceleration sensors of very high accuracy that were developed by Nothrop Grumman LITEF GmbH. We present a low power wakeup multi-hop routing protocol that is able to transmit data with little overhead by supporting the use of wake-up receivers in combination with long-range communication radios. The wireless sensor nodes and the routing protocol are tested at a large-scale highway bridge in south-west Germany, where a prototype network was installed in June 2015 following a first test installation earlier in June at the same bridge. A gateway node equipped with a Global System for Mobile Communications (GSM) modem transfers the network data to a remote server located at the University of Freiburg
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