First record of Megischus brunneus Cresson, 1865 (Hymenoptera: Stephanidae) from Hispaniola, the Antilles

The occurrence of Megischus brunneus Cresson (Hymenoptera: Stephanidae) is recorded for the first time from Hispaniola, the Antilles. The species was previously known from southern Florida and Cuba. This finding further demonstrates the similarities between the Cuban and Hispaniolan biota.Se registra por primera vez la presencia de Megischus brunneus Cresson (Hymenoptera: Stephanidae) para la Hispaniola. Esta especie se conocía anteriormente del sur de la Florida y Cuba. Este hallazgo constituye otro ejemplo de las similaridades de la biota cubana e hispaniolana

Comment on Identification with Taylor Rules: is it indeed impossible? Extended version

Cochrane (2007) points out that the Taylor rule parameters in New-Keynesian models are not identified, and thus trying to estimate them through single-equation regressions is pointless. This paper shows in contrast that this observation holds only for economies that do not display inflation inertia or habit formation. These inherent features of aggregate data allow to correctly identify the parameters of the monetary policy rule by single-equation analysis.monetary economics ;

Exact quasinormal modes for a special class of black holes

Analytic exact expressions for the quasinormal modes of scalar and electromagnetic perturbations around a special class of black holes are found in d\ge3 dimensions. It is shown that, the size of the black hole provides a bound for the angular momentum of the perturbation. Quasinormal modes appear when this bound is fulfilled, otherwise the excitations become purely damped.Comment: 8 pages, no figures. Slightly updated version of the plenary talk given at the General Relativity Conference: "50 Years of FaMAF and Workshop on Global Problems in Relativity", hosted during November 2006 at FaMAF, Universidad Nacional de Cordoba, Cordoba, Argentina

Impossibility of large phase shifts via the "giant Kerr effect" with single-photon wavepackets

An approximate analytical solution is presented, along with numerical calculations, for a system of two single-photon wavepackets interacting via an ideal, localized Kerr medium. It is shown that, because of spontaneous emission into the initially unoccupied temporal modes, the cross-phase modulation in the Schrodinger picture is very small as long as the spectral width of the single-photon pulses is well within the medium's bandwidth. In this limit, the Hamiltonian used can be derived from the "giant Kerr effect" for a four-level atom, under conditions of electromagnetically-induced transparency; it is shown explicitly that the linear absorption in this system increases as the pulse's spectral width approaches the medium's transparency bandwidth, and hence, as long as the absorption probability remains small, the maximum cross-phase modulation is limited to essentially useless values. These results are in agreement with the general, causality- and unitarity-based arguments of Shapiro and co-workers.Comment: 8 pages, 2 figures, to be submitted to Physical Review

Vespidae (Insecta: Hymenoptera) of Puerto Rico, West Indies

The vespid fauna of Greater Puerto Rico is reviewed (Hymenoptera: Vespidae). Three new species are described, Ancistrocerus isla Carpenter, Euodynerus jeitita Carpenter and Genaro, and Omicron aridum Carpenter and Genaro. Polistes crinitus americanus (Fabricius, 1775) and P. crinitus multicolor (Olivier, 1792) are both reduced to synonyms of nominotypical P. crinitus (Felton, 1765), revised status; Zeta abdominale hispaniolae (Bequaert and Salt, 1931) and Zeta abdominale ornatum (de Saussure, 1855) are both reduced to synonyms of nominotypical Zeta abdominale (Drury, 1770), revised status; and Zethus rufinodus monensis Bohart and Stange, 1965, and Zethus rufinodus virginicus Bohart and Stange, 1965, are both reduced to synonyms of nominotypical Zethus rufinodus (Latreille, 1806), revised status. Parancistrocerus obliquus (Cresson, 1865) is newly recorded from Puerto Rico. The presence of Pachodynerus guadulpensis (de Saussure, 1853) in Puerto Rico is confirmed. An analysis of the composition of the Puerto Rican vespid fauna is presented.Se revisa la fauna de avispas de Puerto Rico e islas adyacentes (Hymenoptera: Vespidae). Se describen tres ESPECIES NUEVAS: Ancistrocerus isla Carpenter, Euodynerus jeitita Carpenter y Genaro, y Omicron aridum Carpenter y Genaro. Polistes crinitus americanus (Fabricius, 1775) y P. crinitus multicolor (Olivier, 1792) son reducidas a nombres sinónimos de la especie nominotipica P. crinitus (Felton, 1765), ESTADO REVISADO; Zeta abdominale hispaniolae (Bequaert and Salt, 1931) y Zeta abdominale ornatum (de Saussure, 1855) son reducidas a sinonimia de la especie nominotipica Zeta abdominale (Drury, 1770), ESTADO REVISADO; Zethus rufinodus monensis Bohart y Stange, 1965, y Zethus rufinodus virginicus Bohart y Stange, 1965, son reducidas a nombres sinónimos de la especie nominotipica Zethus rufinodus (Latreille, 1806), ESTADO REVISADO. Parancistrocerus obliquus (Cresson, 1865) se registra nuevamente para Puerto Rico. Se confirma la presencia de Pachodynerus guadulpensis (de Saussure, 1853) en Puerto Rico. Se analiza la composición de la fauna de véspidos de Puerto Rico