9,665 research outputs found
Current status and expected developments in the area of satellite communications in the Latin American and Caribbean region
The present capabilities of various Latin American countries in the area of satellite communications are discussed. Their current needs in this area are covered and how these needs are now being met, as well as prospects for future advancements
A new species of Ptiloglossa from Mexico, with new records of Ptiloglossa cyaniventris from Panama and Costa Rica (Hymenoptera: Colletidae)
A new bee species of the genus Ptiloglossa Smith (Colletidae: Diphaglossinae: Caupolicanini) is described and figured from Jalisco, Mexico, while new records are provided for Ptiloglossa cyaniventris Friese from Panama and a single locality in Costa Rica.  Ptiloglossa chamelensis Ayala & Engel, new species, is endemic to Mexico and is close to P. rugata Moure, both sharing a similar shape in the fused metatibial spur, but in the new species the metatibia is widest at the level of the spur, and the female has black integument with dense yellow pubescence on metasomal terga I–IV.  Ptiloglossa cyaniventris is newly recorded from males collected in Panama and Costa Rica and is characteristic for its dark integument, with intense metallic blue highlights on the metasomal terga, the narrow and long metatibia, and elongate metabasitarsus with an anterior, longitudinal ridge and slightly depressed outer surface
Boundary and expansion effects on two-pion correlation functions in relativistic heavy-ion collisions
We examine the effects that a confining boundary together with hydrodynamical
expansion play on two-pion distributions in relativistic heavy-ion collisions.
We show that the effects arise from the introduction of further correlations
due both to collective motion and the system's finite size. As is well known,
the former leads to a reduction in the apparent source radius with increasing
average pair momentum K. However, for small K, the presence of the boundary
leads to a decrease of the apparent source radius with decreasing K. These two
competing effects produce a maximum for the effective source radius as a
function of K.Comment: 6 pages, 5 Eps figures, uses RevTeX and epsfi
Locating the critical end point using the linear sigma model coupled to quarks
We use the linear sigma model coupled to quarks to compute the effective
potential beyond the mean field approximation, including the contribution of
the ring diagrams at finite temperature and baryon density. We determine the
model couplings and use them to study the phase diagram in the baryon chemical
potential-temperature plane and to locate the Critical End Point.Comment: 8 pages, 2 figures, conference paper from ISMD 201
Pion Mass Modification in presence of external magnetic field
In this work, the self energies of and up to one loop
order have been calculated in the limit of weak external magnetic field. The
effective masses are explicitly dependent on the magnetic field which are
modified significantly for the pseudoscalar coupling due to weak field
approximation of the external field. On the other hand, for the pseudovector
coupling, there is a modest increment in the effective masses of the pions.
These theoretical developments are relevant for the study of the
phenomenological aspect of mesons in the context of neutron stars as well as
heavy ion collisions.Comment: Published in conference proceedings of DAE-HEP-2016 (XXII DAE High
Energy Physics Symposium, New Delhi, India
A new species of Eufriesea from Jalisco, MĂ©xico, with a key to Mexican species of the genus (Hymenoptera: Apidae).
Es wird eine neue Art der Prachtbienengattung Eufriesea Cockerell (Apidae: Apinae: Euglossini) beschrieben. Eufriesea micheneri sp. n. ähnelt allgemein E. caerulescens (Lepeletier de Saint Fargeau) mit ihrem dunklen blauen, purpurn irisierendem Integument, unterscheidet sich aber durch die schwarze Behaarung, dunkle Flügel und beim Männchen durch das grüne Gesicht und die Terminalia. Die neue Art ist bisher von der Sierra del Tuito im Staat Jalisco, Mexiko, bekannt, einem westlichen Teil des Transverse Volcanic Belt. Ein Bestimmungsschlüssel der mexikanischen Eufriesea-Arten ist in Englisch und Spanisch angefügt.ResumenSe describe una nueva especie de abeja del género Eufriesea Cockerell (Apidae: Apinae: Euglossini) con integumento azul oscuro e iridiscencia morada, similar en apariencia a Eufriesea caerulescens (Lepeletier de Saint Fargeau), de la cual puede ser fácilmente diferenciada por presentar pubescencia negra, alas más oscuras y en el caso de los machos el área facial con integumento verde metálico. Esta especie se conoce únicamente para la Sierra del Tuito, en el extremo más Oeste del Eje Volcánico Transversal, en el estado de Jalisco, México. Se incluye una clave para el reconocimiento de las especies mexicanas en ingles y español.StichwörterHymenoptera, Apoidea, Anthophila, Euglossini, taxonomy, México.Nomenklatorische Handlungenmicheneri Ayala & Engel, 2008 (Eufriesea), spec. n.A new species of the orchid bee genus Eufriesea Cockerell (Apidae: Apinae: Euglossini) is described and figured. Eufriesea micheneri sp. n. is generally similar to E. caerulescens (Lepeletier de Saint Fargeau) with is dark blue integument and purple iridescence but differs by its black pubescence, dark wings, and in the male by its green facial integument and terminalia. The new species is known from the Sierra del Tuito in Jalisco State, México, a western part of the Transverse Volcanic Belt. A key for the Mexican species of Eufriesea is provided in English and Spanish.ResumenSe describe una nueva especie de abeja del género Eufriesea Cockerell (Apidae: Apinae: Euglossini) con integumento azul oscuro e iridiscencia morada, similar en apariencia a Eufriesea caerulescens (Lepeletier de Saint Fargeau), de la cual puede ser fácilmente diferenciada por presentar pubescencia negra, alas más oscuras y en el caso de los machos el área facial con integumento verde metálico. Esta especie se conoce únicamente para la Sierra del Tuito, en el extremo más Oeste del Eje Volcánico Transversal, en el estado de Jalisco, México. Se incluye una clave para el reconocimiento de las especies mexicanas en ingles y español.KeywordsHymenoptera, Apoidea, Anthophila, Euglossini, taxonomy, México.Nomenclatural Actsmicheneri Ayala & Engel, 2008 (Eufriesea), spec. n
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