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Financial crisis and international supervision: New evidence on the discretionary use of loan loss provisions at Euro Area commercial banks
We examine the discretionary use of loan loss provisions during the recent financial crisis, when Euro Area banks experienced not only a negatuve effect on the quality of their loans and a reduction in their profitability, but were also subject to a new form of stricter supervision, namely the EBA 2010 and 2011 stress test exercises. Overall, we find support for the only income smoothing hypothesis and we do not observe any difference in listed banks'behavior when compared to unlisted banks. Banks subject to EBA stress tests had higher incentives to smooth income only for the 2011 EBA exercise when a larger and more detailed set of information was released. This may suggest an unwilled side effect that accounting setters and banking regulators and supervisors should account for
Noise Induced Phenomena in the Dynamics of Two Competing Species
Noise through its interaction with the nonlinearity of the living systems can
give rise to counter-intuitive phenomena. In this paper we shortly review noise
induced effects in different ecosystems, in which two populations compete for
the same resources. We also present new results on spatial patterns of two
populations, while modeling real distributions of anchovies and sardines. The
transient dynamics of these ecosystems are analyzed through generalized
Lotka-Volterra equations in the presence of multiplicative noise, which models
the interaction between the species and the environment. We find noise induced
phenomena such as quasi-deterministic oscillations, stochastic resonance, noise
delayed extinction, and noise induced pattern formation. In addition, our
theoretical results are validated with experimental findings. Specifically the
results, obtained by a coupled map lattice model, well reproduce the spatial
distributions of anchovies and sardines, observed in a marine ecosystem.
Moreover, the experimental dynamical behavior of two competing bacterial
populations in a meat product and the probability distribution at long times of
one of them are well reproduced by a stochastic microbial predictive model.Comment: 23 pages, 8 figures; to be published in Math. Model. Nat. Phenom.
(2016
Environmental Noise and Nonlinear Relaxation in Biological Systems
We analyse the effects of environmental noise in three different biological
systems: (i) mating behaviour of individuals of \emph{Nezara viridula} (L.)
(Heteroptera Pentatomidae); (ii) polymer translocation in crowded solution;
(iii) an ecosystem described by a Verhulst model with a multiplicative L\'{e}vy
noise.Comment: 32 pages; In "Ecological Modeling" by Ed. Wen-Jun Zhang. ISBN:
978-1-61324-567-5. - Nova Science Publishers, New York, 201
Enhanced relativistic-electron beam collimation using two consecutive laser pulses
The double laser pulse approach to relativistic electron beam (REB)
collimation has been investigated at the LULI-ELFIE facility. In this scheme,
the magnetic field generated by the first laser-driven REB is used to guide a
second delayed REB. We show how electron beam collimation can be controlled by
properly adjusting laser parameters. By changing the ratio of focus size and
the delay time between the two pulses we found a maximum of electron beam
collimation clearly dependent on the focal spot size ratio of the two laser
pulses and related to the magnetic field dynamics. Cu-K alpha and CTR imaging
diagnostics were implemented to evaluate the collimation effects on the
respectively low energy ( MeV) components of the
REB
Recuperação ambiental em áreas de estepe do Primeiro Planalto Paranaense, mediante plantio de espécies arbóreas.
A diversidade e a intensidade das atividades antrópicas implicam em grandes impactos sobre a vegetação, alterando sua florística, estrutura e funções. A Floresta Ombrófila Mista, assim como as estepes, estão fortemente descaracterizadas, tendo essas últimas poucas e incipientes informações sobre recuperação ambiental. Às margens da represa do Iraí (Região Metropolitana de Curitiba, PR), em área de estepe associada à Floresta Ombrófila Mista, foram realizados plantios com espécies arbóreas como forma de dar início à reconstituição da flora arbórea perdida em decorrência do alagamento. Em meio a esses, foi instalado um experimento com o objetivo de avaliar o crescimento e a sobrevivência de oito espécies arbóreas nativas da região, aos 12 meses, estabelecidas em parcelas monoespecíficas e sob mesmas condições ambientais. Os dados de Escallonia montevidensis, Lafoensia pacari, Lithraea molleoides, Luehea divaricata, Mimosa scabrella, Podocarpus lambertii e Vitex megapotamica foram insatisfatórios, com alturas q ue variaram de 10 a 33 cm, diâmetro de colo entre 2,5 a 6,6 mm e sobrevivência entre 9,1 a 66, 7 %. Atribuíram-se esses resultados a hipóteses como déficit hídrico, solos com dessaturação por bases, época de plantio tardia e evapotranspiração intensificada. Em ações de recuperação ambiental, é necessário considerar os limites e possibilidades referentes à cada unidade fitoecológica e às técnicas de recuperação.Nota Científica
Inner Segment Remodeling and Mitochondrial Translocation in Cone Photoreceptors in Age-Related Macular Degeneration With Outer Retinal Tubulation
PURPOSE: To quantify impressions of mitochondrial translocation in degenerating cones and to determine the nature of accumulated material in the subretinal space with apparent inner segment (IS)-like features by examining cone IS ultrastructure. METHODS: Human donor eyes with advanced age-related macular degeneration (AMD) were screened for outer retinal tubulation (ORT) in macula-wide, high-resolution digital sections. Degenerating cones inside ORT (ORT cones) and outside ORT (non-ORT cones) from AMD eyes and unaffected cones in age-matched control eyes were imaged using transmission electron microscopy. The distances of mitochondria to the external limiting membrane (ELM), cone IS length, and cone IS width at the ELM were measured. RESULTS: Outer retinal tubulation and non-ORT cones lose outer segments (OS), followed by shortening of IS and mitochondria. In non-ORT cones, IS broaden. Outer retinal tubulation and non-ORT cone IS myoids become undetectable due to mitochondria redistribution toward the nucleus. Some ORT cones were found lacking IS and containing mitochondria in the outer fiber (between soma and ELM). Unlike long, thin IS mitochondria in control cones, ORT and non-ORT IS mitochondria are ovoid or reniform. Shed IS, some containing mitochondria, were found in the subretinal space. CONCLUSIONS: In AMD, macula cones exhibit loss of detectable myoid due to IS shortening in addition to OS loss, as described. Mitochondria shrink and translocate toward the nucleus. As reflectivity sources, translocating mitochondria may be detectable using in vivo imaging to monitor photoreceptor degeneration in retinal disorders. These results improve the knowledge basis for interpreting high-resolution clinical retinal imaging
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