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Systemic risk determinants in the European banking industry during financial crises, 2006-2012
The recent financial turmoil has stimulated a rich debate in banking and financial literature on the identification of systemic risk determinants and devices to forecast and prevent crises. This paper explores the contribution of corporate variables to systemic risk using the CoVaR approach (Adrian and Brunnermeier, 2016). Using balanced panel data on 141 European banks from 24 countries, which were listed from 2006Q1 to 2012Q4, we investigated the impact of corporate variables during the three regimes that characterised the European banking sector-the subprime crisis (2007Q3-2008Q3), the European Great Financial Depression (2008Q4-2010Q2), and the sovereign debt crisis (2010Q3-2012Q4). Our results show that size did not play a significant role in spreading systemic risk, while maturity mismatch did. However, the nature and intensity of these two determinants varied across the three regimes
Non Markovian Quantum Repeated Interactions and Measurements
A non-Markovian model of quantum repeated interactions between a small
quantum system and an infinite chain of quantum systems is presented. By
adapting and applying usual pro jection operator techniques in this context,
discrete versions of the integro-differential and time-convolutioness Master
equations for the reduced system are derived. Next, an intuitive and rigorous
description of the indirect quantum measurement principle is developed and a
discrete non Markovian stochastic Master equation for the open system is
obtained. Finally, the question of unravelling in a particular model of
non-Markovian quantum interactions is discussed.Comment: 22 page
Photoassociative spectroscopy at long range in ultracold strontium
We report photoassociative spectroscopy of Sr in a magneto-optical
trap operating on the intercombination line at 689 nm.
Photoassociative transitions are driven with a laser red-detuned by 600-2400
MHz from the atomic resonance at 461 nm. Photoassociation
takes place at extremely large internuclear separation, and the
photoassociative spectrum is strongly affected by relativistic retardation. A
fit of the transition frequencies determines the atomic lifetime
( ns) and resolves a discrepancy between experiment and
recent theoretical calculations.Comment: 4 pages, 4 figures, submitte
Diffusion Approximation of Stochastic Master Equations with Jumps
In the presence of quantum measurements with direct photon detection the
evolution of open quantum systems is usually described by stochastic master
equations with jumps. Heuristically, from these equations one can obtain
diffusion models as approximation. A necessary condition for a general
diffusion approximation for jump master equations is presented. This
approximation is rigorously proved by using techniques for Markov process which
are based upon the convergence of Markov generators and martingale problems.
This result is illustrated by rigorously obtaining the diffusion approximation
for homodyne and heterodyne detection.Comment: 15 page
Conservation laws for vacuum tetrad gravity
Ten conservation laws in useful polynomial form are derived from a Cartan
form and Exterior Differential System (EDS) for the tetrad equations of vacuum
relativity. The Noether construction of conservation laws for well posed EDS is
introduced first, and an illustration given, deriving 15 conservation laws of
the free field Maxwell Equations from symmetries of its EDS. The Maxwell EDS
and tetrad gravity EDS have parallel structures, with their numbers of
dependent variables, numbers of generating 2-forms and generating 3-forms, and
Cartan character tables all in the ratio of 1 to 4. They have 10 corresponding
symmetries with the same Lorentz algebra, and 10 corresponding conservation
laws.Comment: Final version with additional reference
Association between Resistin Levels and All-Cause and Cardiovascular Mortality: A New Study and a Systematic Review and Meta-Analysis.
CONTEXT: Studies concerning the association between circulating resistin and mortality risk have reported, so far, conflicting results.
OBJECTIVE: To investigate the association between resistin and both all-cause and cardiovascular (CV) mortality risk by 1) analyzing data from the Gargano Heart Study (GHS) prospective design (n=359 patients; 81 and 58 all-cause and CV deaths, respectively); 2) performing meta-analyses of all published studies addressing the above mentioned associations.
DATA SOURCE AND STUDY SELECTION: MEDLINE and Web of Science search of studies reporting hazard ratios (HR) of circulating resistin for all-cause or CV mortality.
DATA EXTRACTION: Performed independently by two investigators, using a standardized data extraction sheet.
DATA SYNTHESIS: In GHS, adjusted HRs per one standard deviation (SD) increment in resistin concentration were 1.28 (95% CI: 1.07-1.54) and 1.32 (95% CI: 1.06-1.64) for all-cause and CV mortality, respectively. The meta-analyses included 7 studies (n=4016; 961 events) for all-cause mortality and 6 studies (n=4,187: 412 events) for CV mortality. Pooled HRs per one SD increment in resistin levels were 1.21 (95% CI: 1.03-1.42, Q-test p for heterogeneity<0.001) and 1.05 (95% CI: 1.01-1.10, Q-test p for heterogeneity=0.199) for all-cause and CV mortality, respectively. At meta-regression analyses, study mean age explained 9.9% of all-cause mortality studies heterogeneity. After adjusting for age, HR for all-cause mortality was 1.24 (95% CI: 1.06-1.45).
CONCLUSIONS: Our results provide evidence for an association between circulating resistin and mortality risk among high-risk patients as are those with diabetes and coronary artery disease
Spectroscopic determination of the s-wave scattering lengths of 86Sr and 88Sr
We report the use of photoassociative spectroscopy to determine the ground
state s-wave scattering lengths for the main bosonic isotopes of strontium,
86Sr and 88Sr. Photoassociative transitions are driven with a laser red-detuned
by up to 1400 GHz from the 1S0-1P1 atomic resonance at 461 nm. A minimum in the
transition amplitude for 86Sr at -494+/-5 GHz allows us to determine the
scattering lengths 610a0 < a86 < 2300a0 for 86Sr and a much smaller value of
-1a0 < a88 < 13a0 for 88Sr.Comment: 4 pages, 3 figures, submitted to Physical Review Letter
Radiative feedback from massive black holes in elliptical galaxies. AGN flaring and central starburst fueled by recycled gas
The importance of the radiative feedback from massive black holes at the
centers of elliptical galaxies is not in doubt, given the well established
relations among electromagnetic output, black hole mass and galaxy optical
luminosity. We show how this AGN radiative output affects the hot ISM of an
isolated elliptical galaxy with the aid of a high-resolution hydrodynamical
code, where the cooling and heating functions include photoionization plus
Compton heating. We find that radiative heating is a key factor in the
self-regulated coevolution of massive black holes and their host galaxies and
that 1) the mass accumulated by the central black hole is limited by feedback
to the range observed today, and 2) relaxation instabilities occur so that duty
cycles are small enough (~0.03) to account for the very small fraction of
massive ellipticals observed to be in the "on" -QSO- phase, when the accretion
luminosity approaches the Eddington luminosity. The duty cycle of the hot
bubbles inflated at the galaxy center during major accretion episodes is of the
order of 0.1-0.4. Major accretion episodes caused by cooling flows in the
recycled gas produced by normal stellar evolution trigger nuclear starbursts
coincident with AGN flaring. During such episodes the central sources are often
obscured; but overall, in the bursting phase (1<z<3), the duty cycle of the
black hole in its "on" phase is of the order of percents and it is unobscured
approximately one-third of the time. Mechanical energy output from
non-relativistic gas winds integrates to 2.3 10^{59} erg, with most of it
caused by broadline AGN outflows. [abridged]Comment: ApJ resubmitted. 48 pages, 14 figures (some of them new, bitmapped,
low resolution). New references added, typos correcte
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