14,410 research outputs found
Capital requirements and business cycles with credit market imperfections
The business cycle effects of bank capital regulatory regimes are examined in a New Keynesian model with credit market imperfections and a cost channel of monetary policy. Key features of the model are that bank capital increases incentives for banks to monitor borrowers, thereby reducing the probability of default, and excess capital generates benefits in terms of reduced regulatory scrutiny. Basel I and Basel II-type regulatory regimes are defined, and the model is calibrated for a middle-income country. Simulations of supply and demand shocks show that, depending on the elasticity that relates the repayment probability to the capital-loan ratio, a Basel II-type regime may be less procyclical than a Basel I-type regime.Banks&Banking Reform,Debt Markets,Access to Finance,Economic Theory&Research,Emerging Markets
Cancellation of atmospheric turbulence effects in entangled two-photon beams
Turbulent airflow in the atmosphere and the resulting random fluctuations in
its refractive index have long been known as a major cause of image
deterioration in astronomical imaging and figures among the obstacles for
reliable optical communication when information is encoded in the spatial
profile of a laser beam. Here we show that using correlation imaging and a
suitably prepared source of photon pairs, the most severe of the disturbances
inflicted on the beam by turbulence can be cancelled out. Other than a
two-photon light source, only linear passive optical elements are needed and,
as opposed to adaptive optics techniques, our scheme does not rely on active
wavefront correction.Comment: 5 pages, 3 figure
Elective and primary angioplasty at hospitals without on-site surgery versus with on-site surgery: results from a national registry
INTRODUCTION: Current European clinical guidelines do not restrict interventional cardiology at centers without on-site surgical backup, but disagreement still exists whether hospitals with cardiac catheterization laboratories, but without on-site cardiac surgery, should develop percutaneous coronary intervention (PCI) programs. Technical improvements in equipment and pharmacologic adjunctive therapy have increased the safety margins of diagnostic and therapeutic cardiac catheterization and more than half of the patients treated by PCI in Portugal are treated at hospitals without on-site cardiac surgery.
OBJECTIVES: We set out to compare clinical outcomes of elective and primary PCI for ST-segment elevation myocardial infarction at centers without on-site cardiac surgery with those at centers with on-site cardiac surgery.
METHODS: Based on the Portuguese Registry of Interventional Cardiology, we retrospectively reviewed a total of 13,235 PCI procedures performed from January 2002 to June 2006 and compared the results for 7,112 patients treated at hospitals without on-site cardiac surgery with 6,123 patients treated at hospitals with on-site cardiac surgery.
RESULTS: Demographic data were similar, with a mean age of 64 (55-72) vs. 63 (54-71) years, 75% vs. 76% male and 25.0% vs. 24.2% with diabetes respectively at centers without and with on-site surgical backup. Hospital mortality at centers without and with on-site surgical backup respectively was: chronic angina: 0.3% vs. 0.3% (NS); acute coronary syndromes: 1.5% vs. 1.0% (NS); acute myocardial infarction with ST elevation and without cardiogenic shock: 4.0% vs. 5.0% (NS); cardiogenic shock: 50.9% vs. 53.4% (NS).
CONCLUSIONS: Similar clinical outcomes for interventional cardiology were achieved at hospitals without on-site cardiac surgery and those with on-site cardiac surgery. In the era of coronary stents, adjunctive therapy and experienced operators, elective and primary PCI can safely be performed without on-site surgical backup
Flutuação populacional de insetos-praga na cultura do feijão-caupi no Estado de Roraima.
Avalia a flutuação populacional das principais pragas da cultura do feijão-caupi no Estado de Roraima. O estudo foi realizado com a cultivar de feijão-caupi BRS Mazagão, durante os meses de agosto a outubro no ano de 2006, nos campos experimentais da Embrapa Roraima: Água Boa e Monte Cristo, numa área de 600 m², em cada campo. Durante o estudo, as áreas não receberam nenhuma aplicação de inseticida e os insetos foram coletados semanalmente, utilizando-se o pano de batida, sendo realizadas 10 batidas de pano por semana. A partir dos dados coletados foram avaliadas as flutuações populacionais das principais pragas coletadas ao longo do ciclo da cultura do feijão-caupi. As lagartas desfolhadoras Anticarsia gemmatalis e Pseudoplusia includens ocorreram em frequências muito baixas nas áreas avaliadas e não ocasionaram prejuízos à cultura do feijão-caupi. O percevejo fitófago Nezara viridula e o coleóptero desfolhador Cerotoma arcuata apresentaram seus picos populacionais na fase reprodutiva da cultura
The quadratic spinor Lagrangian, axial torsion current, and generalizations
We show that the Einstein-Hilbert, the Einstein-Palatini, and the Holst
actions can be derived from the Quadratic Spinor Lagrangian (QSL), when the
three classes of Dirac spinor fields, under Lounesto spinor field
classification, are considered. To each one of these classes, there corresponds
a unique kind of action for a covariant gravity theory. In other words, it is
shown to exist a one-to-one correspondence between the three classes of
non-equivalent solutions of the Dirac equation, and Einstein-Hilbert,
Einstein-Palatini, and Holst actions. Furthermore, it arises naturally, from
Lounesto spinor field classification, that any other class of spinor field
(Weyl, Majorana, flagpole, or flag-dipole spinor fields) yields a trivial
(zero) QSL, up to a boundary term. To investigate this boundary term we do not
impose any constraint on the Dirac spinor field, and consequently we obtain new
terms in the boundary component of the QSL. In the particular case of a
teleparallel connection, an axial torsion 1-form current density is obtained.
New terms are also obtained in the corresponding Hamiltonian formalism. We then
discuss how these new terms could shed new light on more general
investigations.Comment: 9 pages, RevTeX, to be published in Int.J.Mod.Phys.D (2007
Produção de semente genética de soja na Embrapa Trigo em 2013/2014.
bitstream/item/114973/1/2014-Documentos-online-151-p25.pd
Efeito do crestamento bacteriano comum na reação de resistência e produção de genótipos de feijoeiro-comum.
O crestamento bacteriano comum (CBC) se destaca entre as doenças bacterianas do feijoeiro-comum (Phaseolus Vulgaris L.) devido a sua ampla incidência no âmbito nacional. A doença é incitada por Xanthomonas axonopodis pv. phaseoli (Xap) e os danos maiores ocorrem em regiões com climas quentes e úmidos. O objetivo deste trabalho foi avaliar a reação de 36 cultivares a diferentes isolados de Xap em condições de campo e estimar a produção de cada genótipo comparando-a com a severidade da doença. Os genótipos que obtiveram notas mais baixas e por conseqüência mostraram-se mais resistentes foram: CNFP 10120, CNFP 10132, BRS Esplendor, CNFC 10438, BRS Timbó e BRS Pitanga. Os genótipos mais suscetíveis foram BRS 9435 Cometa, BRS Expedito, BRSMG Talismã, BRSMG Realce, WAF 75 e Ouro Branco
Caracterização das fases de desenvolvimento e aspectos da biologia do percevejo barriga-verde Dichelops melacanthus (Dallas, 1851).
bitstream/CNPT-2010/40579/1/p-co214.pd
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