869 research outputs found
'Trust is good, control is better': the 1974 Herstatt-Bank crisis and its implications for international regulatory reform
With its international supervisory and regulatory implications, the failure of Bankhaus Herstatt is one of the landmarks of post-war financial history. This article offers the first comprehensive historical account of the Herstatt crisis, and contributes to the wider discussions on international supervisory and regulatory reform since the mid-1970s, including regulatory capture, markets' self-regulation and resolution of failed banks. In doing so, it first argues that contrary to a widely held view, the German authorities received early and repeated warnings about Herstatt's dealings but this involved only limited and ineffective regulatory/supervisory responses, then it turns to the actual collapse of the bank in June 1974, and finally explores the wider regulatory issues raised by the Herstatt case
Thermal UAS survey of reactivated hot spring activity in Waiwera, New Zealand
The utilization of geothermal reservoirs as alternative energy source is becoming increasingly important worldwide. Through close-range aerial photogrammetry realized by unmanned aircraft systems (UAS), this study investigates the surface expression of a leaking warm water reservoir in Waiwera, New Zealand, that has been known for many centuries but remained little explored. Due to overproduction during the 1960s and 1970s the reservoir has suffered significant pressure reduction, which resulted in the loss of artesian conditions and led to the desiccation of the hot springs in close succession. However, shortly after the recent shutdown of the primary user (Waiwera Thermal Resort & Spa) renewed artesian activity was reported by locals but no hot spring activity has been observed so far. Therefore, this study was carried out in October 2019 to assess the actual conditions of thermal activity in the area of the former hot springs. UAS with coupled thermal infrared cameras were used for thermal mapping and the obtained data show renewed activity of the hot springs on the beachfront of Waiwera. Faults and fractures were identified as important fluid pathways, as well as individual fluid conducting lithologies
Relativistic and Radiative Corrections to the Mollow Spectrum
The incoherent, inelastic part of the resonance fluorescence spectrum of a
laser-driven atom is known as the Mollow spectrum [B. R. Mollow, Phys. Rev.
188, 1969 (1969)]. Starting from this level of description, we discuss
theoretical foundations of high-precision spectroscopy using the resonance
fluorescence light of strongly laser-driven atoms. Specifically, we evaluate
the leading relativistic and radiative corrections to the Mollow spectrum, up
to the relative orders of (Z alpha)^2 and alpha(Z alpha)^2, respectively, and
Bloch-Siegert shifts as well as stimulated radiative corrections involving
off-resonant virtual states. Complete results are provided for the hydrogen
1S-2P_{1/2} and 1S-2P_{3/2} transitions; these include all relevant correction
terms up to the specified order of approximation and could directly be compared
to experimental data. As an application, the outcome of such experiments would
allow for a sensitive test of the validity of the dressed-state basis as the
natural description of the combined atom-laser system.Comment: 20 pages, 1 figure; RevTe
Direct costs and cost-effectiveness of dual-source computed tomography and invasive coronary angiography in patients with an intermediate pretest likelihood for coronary artery disease
The study aims to determine the direct costs and comparative cost-effectiveness of latest-generation dual-source computed tomography (DSCT) and invasive coronary angiography for diagnosing coronary artery disease (CAD) in patients suspected of having this disease
Pair production in laser fields oscillating in space and time
The production of electron-positron pairs from vacuum by counterpropagating
laser beams of linear polarization is calculated. In contrast to the usual
approximate approach, the spatial dependence and magnetic component of the
laser field are taken into account. We show that the latter strongly affects
the creation process at high laser frequency: the production probability is
reduced, the kinematics is fundamentally modified, the resonant
Rabi-oscillation pattern is distorted and the resonance positions are shifted,
multiplied and split.Comment: 5 pages, 5 figure
Determination of Pericardial Adipose Tissue Increases the Prognostic Accuracy of Coronary Artery Calcification for Future Cardiovascular Events
Objectives: Pericardial adipose tissue (PAT) is associated with coronary artery plaque accumulation and the incidence of coronary heart disease. We evaluated the possible incremental prognostic value of PAT for future cardiovascular events. Methods: 145 patients (94 males, age 60 10 years) with stable coronary artery disease underwent coronary artery calcification (CAC) scanning in a multislice CT scanner, and the volume of pericardial fat was measured. Mean observation time was 5.4 years. Results: 34 patients experienced a severe cardiac event. They had a significantly higher CAC score (1,708 +/- 2,269 vs. 538 +/- 1,150, p 400, 3.5 (1.9-5.4; p = 0.007) for scores > 800 and 5.9 (3.7-7.8; p = 0.005) for scores > 1,600. When additionally a PAT volume > 200 cm(3) was determined, there was a significant increase in the event rate and relative risk. We calculated a relative risk of 2.9 (1.9-4.2; p = 0.01) for scores > 400, 4.0 (2.1-5.0; p = 0.006) for scores > 800 and 7.1 (4.1-10.2; p = 0.005) for scores > 1,600. Conclusions:The additional determination of PAT increases the predictive power of CAC for future cardiovascular events. PAT might therefore be used as a further parameter for risk stratification. Copyright (C) 2012 S. Karger AG, Base
Characterizing the Cool KOIs. VI. H- and K-band Spectra of Kepler M Dwarf Planet-Candidate Hosts
We present H- and K-band spectra for late-type Kepler Objects of Interest
(the "Cool KOIs"): low-mass stars with transiting-planet candidates discovered
by NASA's Kepler Mission that are listed on the NASA Exoplanet Archive. We
acquired spectra of 103 Cool KOIs and used the indices and calibrations of
Rojas-Ayala et al. to determine their spectral types, stellar effective
temperatures and metallicities, significantly augmenting previously published
values. We interpolate our measured effective temperatures and metallicities
onto evolutionary isochrones to determine stellar masses, radii, luminosities
and distances, assuming the stars have settled onto the main-sequence. As a
choice of isochrones, we use a new suite of Dartmouth predictions that reliably
include mid-to-late M dwarf stars. We identify five M4V stars: KOI-961
(confirmed as Kepler 42), KOI-2704, KOI-2842, KOI-4290, and the secondary
component to visual binary KOI-1725, which we call KOI-1725 B. We also identify
a peculiar star, KOI-3497, which has a Na and Ca lines consistent with a dwarf
star but CO lines consistent with a giant. Visible-wavelength adaptive optics
imaging reveals two objects within a 1 arc second diameter; however, the
objects' colors are peculiar. The spectra and properties presented in this
paper serve as a resource for prioritizing follow-up observations and planet
validation efforts for the Cool KOIs, and are all available for download online
using the "data behind the figure" feature.Comment: Accepted for publication in the Astrophysical Journal Supplement
Series (ApJS). Data and table are available in the sourc
Investigation of Single Boron Acceptors at the Cleaved Si:B (111) Surface
The cleaved and (2 x 1) reconstructed (111) surface of p-type Si is
investigated by scanning tunneling microscopy (STM). Single B acceptors are
identified due to their characteristic voltage-dependent contrast which is
explained by a local energetic shift of the electronic density of states caused
by the Coulomb potential of the negatively charged acceptor. In addition,
detailed analysis of the STM images shows that apparently one orbital is
missing at the B site at sample voltages of 0.4 - 0.6 V, corresponding to the
absence of a localized dangling-bond state. Scanning tunneling spectroscopy
confirms a strongly altered density of states at the B atom due to the
different electronic structure of B compared to Si.Comment: 6 pages, 7 figure
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