1,576 research outputs found
The banking sector and recovery in the EU economy
Banks within Europe have become larger and more international as Europe has moved towards a unified financial services market, but this trend has been reversed since the crisis. In order to establish the effect of these structural changes on output in Europe, we use a micro data set to investigate the impact of size (as measured by asset size) on banks’ net interest margins. We show that larger banks offer lower borrowing costs for firms, which raises sustainable output. We then use NiGEM to look at the impact of banks becoming smaller and moving back into their home territory. We investigate the impacts on output according to country size, showing that the effects are generally larger in small countries, and also larger in economies that are more dependent on bank finance for their business investment decisions.
Keywords: Net interest margins; bank size; European financial integration; growth; bank regulation
JEL Classifications: E44; G10; G2
Submicrosecond comparisons of time standards via the Navigation Technology Satellites (NTS)
An interim demonstration was performed of the time transfer capability of the NAVSTAR GPS system using a single NTS satellite. Measurements of time difference (pseudo-range) are made from the NTS tracking network and at the participating observatories. The NTS network measurements are used to compute the NTS orbit trajectory. The central NTS tracking station has a time link to the Naval Observatory UTC (USNO,MC1) master clock. Measurements are used with the NTS receiver at the remote observatory, the time transfer value UTC (USNO,MC1)-UTC (REMOTE, VIA NTS) is calculated. Intercomparisons were computed using predicted values of satellite clock offset and ephemeus
Submicrosecond comparison of international clock synchronization by VLBI and the NTS satellite
The intercontinental clock synchronization capabilities of Very Long Baseline Interferometry (VLBI) and the Navigation Technology Satellite (NTS) were compared using both methods to synchronize the Cesium clocks at the NASA Deep Space Net complexes at Madrid, Spain and Goldstone, California. Verification of the accuracy of both systems was examined. The VLBI experiments used the Wideband VLBI Data Acquisition System developed at the NASA Jet Propulsion Laboratory. The NTS Satellites were designed and built by the Naval Research Laboratory used with NTS Timing Receivers developed by the Goddard Space Flight Center. The two methods agreed at about the one-half microsecond level
Tidal Disruption of Protoclusters in Giant Molecular Clouds
We study the collapse of protoclusters within a giant molecular cloud (GMC)
to determine the conditions under which collapse is significantly disrupted.
Motivated by observations of star forming regions which exhibit flattened cloud
structures, this study considers collapsing protoclusters with disk geometries.
The collapse of a 10^3 Msun protocluster initially a distance of 2-10 pc from a
10^3 - 10^6 Msun point mass is numerically calculated. Simulations with zero
initial relative velocity between the two are completed as well as simulations
with relative velocities consistent with those observed in GMCs. The results
allow us to define the conditions under which it is safe to assume protocluster
collapse proceeds as if in isolation. For instance, we find the collapse of a
10^3 Msun protocluster will be significantly disrupted if it is within 2-4 pc
of a 10^4 Msun point mass. Thus, the collapse of a 10^3 Msun protocluster can
be considered to proceed as if in isolation if it is more than ~ 4 pc away from
a 10^4 Msun compact object. In addition, in no portion of the sampled parameter
space does the gravitational interaction between the protocluster disk and the
massive particle significantly disperse the disk into the background GMC. We
discuss the distribution of clusters of young stellar objects within the
Perseus and Mon R2 star forming regions, which are consistent with the results
of our simulations and the limitations of our results in gas dominated regions
such as the Orion cloud.Comment: 12 pages, 6 figures, Accepted for publication in Ap
Radiative transfer and the energy equation in SPH simulations of star formation
We introduce and test a new and highly efficient method for treating the
thermal and radiative effects influencing the energy equation in SPH
simulations of star formation. The method uses the density, temperature and
gravitational potential of each particle to estimate a mean optical depth,
which then regulates the particle's heating and cooling. The method captures --
at minimal computational cost -- the effects of (i) the rotational and
vibrational degrees of freedom of H2, H2 dissociation, H0 ionisation, (ii)
opacity changes due to ice mantle melting, sublimation of dust, molecular
lines, H-, bound-free and free-free processes and electron scattering; (iv)
external irradiation; and (v) thermal inertia. The new algorithm reproduces the
results of previous authors and/or known analytic solutions. The computational
cost is comparable to a standard SPH simulation with a simple barotropic
equation of state. The method is easy to implement, can be applied to both
particle- and grid-based codes, and handles optical depths 0<tau<10^{11}.Comment: Submitted to A&A, recommended for publicatio
A radiation driven implosion model for the enhanced luminosity of protostars near HII regions
Context. Molecular clouds near the H II regions tend to harbor more luminous
protostars. Aims. Our aim in this paper is to investigate whether or not
radiation-driven implosion mechanism enhances luminosity of protostars near
regions of high-ionizing fluxes. Methods. We performed numerical simulations to
model collapse of cores exposed to UV radiation from O stars. We investigated
dependence of mass loss rates on the initial density profiles of cores and
variation of UV fluxes. We derived simple analytic estimates of accretion rates
and final masses of protostars. Results. Radiation-driven implosion mechanism
can increase accretion rates of protostars by 1-2 orders of magnitude. On the
other hand, mass loss due to photo-evaporation is not large enough to have a
significant impact on the luminosity. The increase of accretion rate makes
luminosity 1-2 orders higher than those of protostars that form without
external triggering. Conclusions. Radiation-driven implosion can help explain
the observed higher luminosity of protostars in molecular clouds near H II
regions.Comment: 9 pages, 6 figures, accepted for publication in Astronomy and
Astrophysic
Amplified fragment length polymorphism analysis supports the valid separate species status of Lucilia caesar and L. illustris (Diptera: Calliphoridae)
Common DNA-based species determination methods fail to distinguish some blow flies in the forensically and medically important genus Lucilia Robineau-Desvoidy. This is a practical problem, and it has also been interpreted as casting doubt on the validity of some morphologically defined species. An example is Lucilia illustris and L. caesar, which co-occur in Europe whilst only L. illustris has been collected in North America. Reports that these species shared both mitochondrial and nuclear gene sequences, along with claims that diagnostic morphological characters are difficult to interpret, were used to question their separate species status. We report here that amplified fragment length polymorphism profiles strongly support the validity of both species based on both assignment and phylogenetic analysis, and that traditional identification criteria based on male and female genital morphology are more reliable than has been claimed.publishedVersio
Transcriptional changes when Myxococcus xanthus preys on Escherichia coli suggest myxobacterial predators are constitutively toxic but regulate their feeding
Predation is a fundamental ecological process, but within most microbial ecosystems the molecular mechanisms of predation remain poorly understood. We investigated transcriptome changes associated with the predation of Escherichia coli by the myxobacterium Myxococcus xanthus using mRNA sequencing. Exposure to pre-killed prey significantly altered expression of 1319 predator genes. However, the transcriptional response to living prey was minimal, with only 12 genes being significantly up-regulated. The genes most induced by prey presence (kdpA and kdpB, members of the kdp regulon) were confirmed by reverse transcriptase quantitative PCR to be regulated by osmotic shock in M. xanthus, suggesting indirect sensing of prey. However, the prey showed extensive transcriptome changes when co-cultured with predator, with 40?% of its genes (1534) showing significant changes in expression. Bacteriolytic M. xanthus culture supernatant and secreted outer membrane vesicles (OMVs) also induced changes in expression of large numbers of prey genes (598 and 461, respectively). Five metabolic pathways were significantly enriched in prey genes up-regulated on exposure to OMVs, supernatant and/or predatory cells, including those for ribosome and lipopolysaccharide production, suggesting that the prey cell wall and protein production are primary targets of the predator?s attack. Our data suggest a model of the myxobacterial predatome (genes and proteins associated with predation) in which the predator constitutively produces secretions which disable its prey whilst simultaneously generating a signal that prey is present. That signal then triggers a regulated feeding response in the predatorpublishersversionPeer reviewe
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