4,202 research outputs found
Two species of Compsus Schoenherr, new citrus pests from Colombia (Coleoptera: Curculionidae: Entiminae)
Two species of the weevil genus Compsus Schoenherr (Coleoptera: Curculionidae: Entiminae) from Colombia are redescribed: C. obliquatus Hustache and C.viridivittatus (Guérin-Méneville). A key by Hustache in 1938, to 33 of the 34 recognized species of Colombian Compsus then known, is modified to include the one additional species. Habitus illustrations of males and females of the two species and illustrations of selected parts of the male and female genitalia are included. Nearly all of the specimens of these two species were collected on various species or varieties of citrus, indicating their potential as citrus pests in the future.Se redescriben dos especies de picudos del genero Compsus Schoenherr (Coleoptera: Curculionidae: Entiminae) colectadas en Colombia: C. obliquatus Hustache y C. viridivittatus (Guérin-Méneville). Se modifica la clave de identificación de Hustache de 1938 la cual incluye 33 a 34 especies conocidas de Compsus en ese entonces en Colombia. Se incluyen ilustraciones con las características físicas de machos y hembras de ambas especies e
ilustraciones de partes seleccionadas de la genitalia de machos y hembras de las dos especies. Casi todos los especímenes de estas dos especies fueron colectadas en varias especies o variedades de cítricos, lo cual indica su futuro potencial como plagas de cítricos
Global three-neutrino oscillation analysis of neutrino data
A global analysis of the solar, atmospheric and reactor neutrino data is
presented in terms of three-neutrino oscillations. We include the most recent
solar neutrino rates of Homestake, SAGE, GALLEX and GNO, as well as the recent
1117 day Super-Kamiokande data sample, including the recoil electron energy
spectrum both for day and night periods and we treat in a unified way the full
parameter space for oscillations, correctly accounting for the transition from
the matter enhanced (MSW) to the vacuum oscillations regime. Likewise, we
include in our description conversions with . For the
atmospheric data we perform our analysis of the contained events and the
upward-going -induced muon fluxes, including the previous data samples of
Frejus, IMB, Nusex, and Kamioka experiments as well as the full 71 kton-yr
(1144 days) Super-Kamiokande data set, the recent 5.1 kton-yr contained events
of Soudan2 and the results on upgoing muons from the MACRO detector. We first
present the allowed regions of solar and atmospheric oscillation parameters
, and , ,
respectively, as a function of and determine the constraints from
atmospheric and solar data on the mixing angle , common to solar
and atmospheric analyses. We also obtain the allowed ranges of parameters from
the full five-dimensional combined analysis of the solar, atmospheric and
reactor data.Comment: 56 pages, 21 postscript figures. Some misprints corrected and new
references added. Chooz limit included in Fig.21. Final version to appear in
Phys. Rev.
Seasonal Dependence in the Solar Neutrino Flux
MSW solutions of the solar neutrino problem predict a seasonal dependence of
the zenith angle distribution of the event rates, due to the non-zero latitude
at the Super-Kamiokande site. We calculate this seasonal dependence and compare
it with the expectations in the no-oscillation case as well as just-so
scenario, in the light of the latest Super-Kamiokande 708-day data. The
seasonal dependence can be sizeable in the large mixing angle MSW solution and
would be correlated with the day-night effect. This may be used to discriminate
between MSW and just-so scenarios and should be taken into account in refined
fits of the data.Comment: 4 pages, latex, RevTeX, two postscript figure
V346 Nor: the post-outburst life of a peculiar young eruptive star
FU Orionis-type objects (FUors) are young low-mass stars undergoing powerful accretion outbursts. The increased accretion is often accompanied by collimated jets and energetic, large-scale molecular outflows. The extra heating during the outburst may also induce detectable geometrical, chemical, and mineralogical changes in the circumstellar material, affecting possible planet formation around these objects. V346 Nor is a southern FUor with peculiar spectral characteristics. Decades after the beginning of its outburst, it unexpectedly underwent a fading event around 2010 due to a decrease in the mass accretion rate onto the star by at least two orders of magnitude. Here we present optical and near-infrared photometry and spectroscopy obtained after the minimum. Our light curves show a gradual re-brightening of V346 Nor, with its K s-band brightness only 1.5 mag below the outburst brightness level. Our Very Large Telescope (VLT)/XSHOOTER spectroscopic observations display several strong forbidden emission lines toward the source from various metals and molecular hydrogen, suggesting the launch of a new jet. Our N-band spectrum obtained with VLT/VISIR outlines a deeper silicate absorption feature than before, indicating that the geometry of the circumstellar medium has changed in the post-outburst period compared to peak brightness.Peer reviewedFinal Published versio
Exploring the use of dynamic language assessment with deaf children, who use American Sign Language: Two case studies
We describe a model for assessment of lexical-semantic organization skills in American Sign Language (ASL) within the framework of dynamic vocabulary assessment and discuss the applicability and validity of the use of mediated learning experiences (MLE) with deaf signing children. Two elementary students (ages 7;6 and 8;4) completed a set of four vocabulary tasks and received two 30-minute mediations in ASL. Each session consisted of several scripted activities focusing on the use of categorization. Both had experienced difficulties in providing categorically related responses in one of the vocabulary tasks used previously. Results showed that the two students exhibited notable differences with regards to their learning pace, information uptake, and effort required by the mediator. Furthermore, we observed signs of a shift in strategic behavior by the lower performing student during the second mediation. Results suggest that the use of dynamic assessment procedures in a vocabulary context was helpful in understanding children's strategies as related to learning potential. These results are discussed in terms of deaf children's cognitive modifiability with implications for planning instruction and how MLE can be used with a population that uses ASL
Impact of general reionization scenarios on extraction of inflationary parameters
Determination of whether the Harrison--Zel'dovich spectrum for primordial
scalar perturbations is consistent with observations is sensitive to
assumptions about the reionization scenario. In light of this result, we
revisit constraints on inflationary models using more general reionization
scenarios. While the bounds on the tensor-to-scalar ratio are largely
unmodified, when different reionization schemes are addressed, hybrid models
are back into the inflationary game. In the general reionization picture, we
reconstruct both the shape and amplitude of the inflaton potential. We find a
broader spectrum of potential shapes when relaxing the simple reionization
restriction. An upper limit of GeV to the amplitude of the potential
is found, regardless of the assumptions on the reionization history.Comment: 10 Pages, 9 figure
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