8,033 research outputs found
Cyclical Effects of Bank Capital Buffers with Imperfect Credit Markets: international evidence
This paper analyzes the cyclical effects of bank capital buffers using an international sample of 2,361 banks from 92 countries over the 1990-2007 period. We find that capital buffers reduce the bank credit supply but â through what could be âmonitoring or signaling effectsâ â have also an expansionary effect on economic activity by reducing lending and deposit rate spreads. This influence on lending and deposit rate spreads is more pronunced in developing countries and during downturns. The results suggest that capital buffers have a counter-cyclical effect in these countries. Our data do not suggest differences in the cyclical effects of capital buffers between Basel I and Basel II.
TD-DFT Monitoring of the Absorption Spectra of Polycyclic Aromatic Hydrocarbons over the Basque Country, Spain
Brown carbon is a type of carbonaceous aerosol with strong light absorption in the ultraviolet and visible wavelengths that leads to radiative forcing. However, it is difficult to correlate the chemical composition of brown carbon with its atmospheric light absorption properties, which translates into significant uncertainty. Thus, a time-dependent density functional theory (TD-DFT) approach was used to model the real-world absorption properties of 14 polycyclic aromatic hydrocarbons (PAHs) over three regions of the Basque Country (Spain): Bilbao, Urretxu, and Azpeitia. The data were corrected for atmospheric concentration. The results show that the absorption spectra over each region are qualitatively identical, with the absorption intensities being significantly higher over Bilbao than over Azpeitia and Urretxu. Furthermore, it was found that the light absorption by PAHs should be more relevant for radiative forcing when it occurs at UVA and (sub)visible wavelengths. Finally, among the 14 studied PAHs, benzo[b]fluoranthene, pyrene, fluoranthene, benzo[a]pyrene, and benzo[k]fluoranthene and benzoperylene were identified as the molecules with larger contributions to radiative forcing.</jats:p
Some Lessons for the Future from the Global Malaria Eradication Programme (1955â1969)
Jose Najera and colleagues identify lessons from the Global Malaria Eradication Programme (1955â1969) relevant to current elimination and eradication efforts
A new population of Darwin's fox (Lycalopex fulvipes) in the Valdivian Coastal Range
IndexaciĂłn: Web of Science; Scielo.Darwin's fox (Lycalopex fulvipes Martin, 1837) is an endemic of the temperate forests of the Coastal Range of southern Chile, that was reported by Charles Darwin in 1834 in southern ChiloĂ© Island (42° S, 74° W; Martin 1837). Initially known exclusively from that island, it was considered both an insular subspecies of the chilla fox (Lycalopex griseus Gray, 1837) (Housse 1953; Clutton-Brock et al. 1976) and a valid species (Martin 1837; Gay 1947; Osgood 1943). In 1990, a mainland population was reported at Nahuelbuta National Park (ca. 450 km north of ChiloĂ© Island, 37° 47âČ S, 72° 59âČ W; Figure 1a) in sympatry with the chilla and culpeo foxes (Lycalopex culpaeus Molina, 1782) (Jaksic et al. 1990; Medel et al. 1990; JimĂ©nez et al. 1991). This supported its status as a valid species, later confirmed through genetic studies (Yahnke et al. 1996).http://ref.scielo.org/z7mmt
Non-Invasive measurer for methane and carbone dioxide emissions in bovine cattle through TRIZ
Greenhouse gases (GHG), mainly methane (CH4) and carbon dioxide (CO2), can be
generated in agricultural activities, not only in waste but also in the process of breathing of
livestock. The Theory of Inventive Problem Solving (TRIZ) is an innovative Russian
methodology that allows finding the solution to a problem raised. This paper presents the use of
two TRIZ tools to design a non-invasive prototype that detects CH4 and CO2 emitted by cattle in
real time. The tools were the matrix of technical contradictions and the nine-screen analysis with
which the parameter to be improved (A) was found and the best possible solution to design a
prototype that allows quantifying gases for animal welfare, Final Ideal Result (IFR) a wireless
module with a sensor system for each of the gases placed on the bovine head, which convert the
detected gas into an electrical signal to be sent wirelessly to a range of 1.5 km in free space at a
receiver for its visualization representing the parts per million (ppm) of CH4 and CO2 that the
bovine is generating during the measurement
Paleo and historical seismicity in Mallorca (Baleares, Spain): a preliminary approach
The island of Mallorca is subject to low seismic activity. The instrumental record shows that current seismicity is surficial (<10 km depth) and low in magnitude (mb<4). Both historical and geological records display the occurrence of strong events, e.g. the 1851 Palma earthquake (VIII, MSK intensity). Data on this destruct ive event indicate that this was a seven month long seismic sequence, with two strong events, causing severe damage and collapse of buildings along Palma bay in addition to moderate ground collapses in the macroseismal zone. The earthquake epicenter was situated between Sa Cabaneta and Sta. EugĂšnia. This earthquake can be correlated with the trace of the Sencelles fault, the main extensional structure of the island on the surface. The geological and geophysical analyses of recent surface faulting features at the Portol doline (reverse surface faulting) and on the Sta. EugĂšnia segment of the Sencelles fault (bedrock fault scarp ) suggest recurrent large prehistoric events. Preliminary data show minimum vertical offsets of 2.56 m at the Portol doline and offsets of 3.50m at the Sta. EugĂšnia bedrock fault scarp. These offsets were accumulated in recent times (Holocene?). Displacements per event can be initially estimated as mean values of 0.88 to 0.40 m in both places, but larger offsets of a maximum of 1.68 m can also be inferred. Specific dendrochronologic, lichenometric, and weathering analyses to assess true single-event slip values, and their time-bracketing will be necessary. The interpretation of these displacement events in terms of earthquake magnitude is not straightforward because of the apparent subordinate nature of the ground rupture at the Po rtol doline and the possible influence of salt tectonics in both places. To address these issues, a fault-trench was planned along the Sencelles fault within the framework of a new research project. The Spanish seismic code (NCS94) assigns an expected maximum ground acceleration of 0.04 g for a 500 year return period to the area. In the light of our data these values are underestimated. The historical and geological records indicate the occurrence of historical VII to VIII MSK, and stronger prehistoric events. Peak ground horizontal accelerations of up to 0.10 g could be expected during modern earthquakes
Extragalactic source contributions to arcminute-scale Cosmic Microwave Background anisotropies
The possible contributions of the various classes of extragalactic sources
(including, in addition to the canonical radio sources, GHz Peaked Spectrum
sources, advection-dominated sources, starburst galaxies, high-redshift
proto-spheroidal galaxies) to the arcminute scale fluctuations measured by the
CBI, BIMA, and ACBAR experiments are discussed. At 30 GHz, fluctuations due to
radio sources undetected by ancillary low-frequency surveys may be higher than
estimated by the CBI and BIMA groups. High-redshift dusty galaxies, whose
fluctuations may be strongly enhanced by the effect of clustering, could
contribute to the BIMA excess signal, and dominate at 150 GHz (the ACBAR
frequency). Moreover, in the present data situation, the dust emission of these
high-redshift sources set an unavoidable limit to the detection of primordial
CMB anisotropies at high multipoles, even at frequencies as low as
GHz. It is concluded that the possibility that the excess power at high
multipoles is dominated by unsubtracted extragalactic sources cannot be ruled
out. On the other hand, there is room for a contribution from the
Sunyaev-Zeldovich effect within clusters of galaxies, with a density
fluctuation amplitude parameter consistent with the values preferred
by current data.Comment: 7 pages, 3 figures, A&A in pres
The colored Hanbury Brown--Twiss effect
The Hanbury Brown--Twiss effect is one of the celebrated phenomenologies of
modern physics that accommodates equally well classical (interferences of
waves) and quantum (correlations between indistinguishable particles)
interpretations. The effect was discovered in the late thirties with a basic
observation of Hanbury Brown that radio-pulses from two distinct antennas
generate signals on the oscilloscope that wiggle similarly to the naked eye.
When Hanbury Brown and his mathematician colleague Twiss took the obvious step
to propose bringing the effect in the optical range, they met with considerable
opposition as single-photon interferences were deemed impossible. The Hanbury
Brown--Twiss effect is nowadays universally accepted and, being so fundamental,
embodies many subtleties of our understanding of the wave/particle dual nature
of light. Thanks to a novel experimental technique, we report here a
generalized version of the Hanbury Brown--Twiss effect to include the frequency
of the detected light, or, from the particle point of view, the energy of the
detected photons. In addition to the known tendencies of indistinguishable
photons to arrive together on the detector, we find that photons of different
colors present the opposite characteristic of avoiding each others. We
postulate that fermions can be similarly brought to exhibit positive
(boson-like) correlations by frequency filtering.Comment: 18 pages, includes supplementary material of the derivation
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