442 research outputs found
New Distributional Record for \u3ci\u3eBalcha Indica\u3c/i\u3e (Hymenoptera: Eupelmidae) in Eastern West Virginia Discovered During Emerald Ash Borer Parasitoid Recovery Surveys
Between 2010 and 2012, approximately 6,300 Spathius agrili Yang (Hymenoptera: Braconidae) and 9,500 Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae) parasitoids were released for biological control of the invasive emerald ash borer, Agrilus planipennis Fairmaire, at Cacapon State Park and the Cool Front Development in Morgan County, West Virginia. The invasive beetle was first detected there in 2009, and extensive ash mortality is currently occurring. We conducted parasitoid recovery surveys in 2013 but did not recover either of the released parasitoid species. However, we did rear Balcha indica Mani and Kaul (Hymenoptera: Eupelmidae), which is native to Asia and is a documented parasitoid of A. planipennis, from bolts infested with A. planipennis. This is the first documented record of B. indica for West Virginia
Temporal and Spatial Distribution of Imidacloprid and the Arthropod Fauna Associated with Eastern Hemlock, Tsuga canadensis (L.) Carr
Eastern hemlock, Tsuga canadensis (L.) Carr (Pinales: Pinaceae), is an important component of both the urban and forest landscape of the eastern United States. Eastern hemlock has been heavily impacted by the introduction of the hemlock woolly adelgid, Adelges tsugae (Annand) (Hemiptera: Adelgidae). Two goals of this research were (1) to determine the effect of treatment timing (spring versus fall) and application method (tree injection versus soil injection) on the spatial and temporal distribution of imidacloprid the primary insecticide used to treat A. tsugae and (2) to assess the impact of application method and timing of imidacloprid treatments on the arthropods associated with eastern hemlock. The results of this study showed that xylem fluid concentrations of imidacloprid were significantly (P \u3c 0.05) higher for spring applications than for fall applications, and for trunk injections than soil injections in the first year post treatment. A diverse group of arthropods, making up 393 species, were collected by branch beating the lower crowns of eastern hemlock. No significant (P \u3e 0.05) differences in arthropod abundance were found between imidacloprid treated and control trees and application methods. An extensive literature review revealed 484 native and exotic arthropods from three different taxonomic classes and 21 different orders associated with eastern hemlock in North America. A total of five arthropod species were eastern hemlock dependent, and are likely to experience local extirpation as a result of declining and dying eastern hemlock. In addition, an assessment of the impact of application method and timing of imidacloprid treatments on the spider communities were carried out because spiders are the primary arthropod predator present in the crown of eastern hemlock. No significant (P \u3e 0.05) differences in spider abundance were found between imidacloprid treated and control trees and application methods. This study provides fundamental information to aid the conservation and management of eastern hemlock and biodivisity at risk due to extensive applications of imidacloprid
Diffusion and pulsations in slowly rotating B stars
Diffusion in cool B stars of the main sequence has been shown to strongly
affect opacities and convection in cool B stars of the main sequence. We show
here that diffusion in B stars maintains or enhances the excitation of
pulsations in these stars. This result conflicts with observations as cool B
stars that show evidence of diffusion, the HgMn stars, are stable to the
current detection level. We discuss possible implications of this discrepancy
for the models.Comment: 4 pages, 1 figure, in Element stratification in stars: 40 years of
atomic diffusio
Toxicity issues pertaining to burning pyrotechnics
International audienceWe all know that normal operations with pyrotechnic compositions or other energetic materials, apart from the desired effect (e.g.: controlled blast from high explosives, propulsive power resulting from propellant gas pressure, various visible or sound effects from fireworks...) lead to the release of various products (gases, vapours, aerosols) in the environment, in relation with the chemicals, the reactions involved and some physical parameters. Although discussed from time to time by experts, and contrary to the case of 'conventional' fires, toxicity and environmentally related questions associated with burning pyrotechnics, have received far less attention than they actually deserve. Therefore, this paper supports an analysis of our current understanding of the sole toxicity problems (acute toxicity, sub-acute toxicity concerns...) emerging with all types of burning pyrotechnics, at the light of what has been established to address 'normal' fires in built environments. The paper provides an analysis of the regulatory context, lessons from past accidents, typology of chemistry and reactions of pyrotechnics, and some contribution to the analysis is supported by experiments on smoke powders, one significant family of products belonging to pyrotechnics. Eventually, a discussion is proposed to envisage pathways to go further in learning on those important issues
Bonus est vir scribendi peritus : Les scholia comme outils d'enseignement du latin Ă Rome
C’est au IVe siècle que le grammairien romain Maurus Servius Honoratus compose son commentaire sur l’Énéide de Virgile. Ce recueil de commentaires, ou scholia, a notamment comme objectif l’enseignement d’une langue normative guidé par les principes de la latinitas : le latin conforme aux principes grammaticaux. Malgré la place centrale qu’occupe depuis longtemps l’Énéide dans l’éducation et la culture latine, Servius voue une grande partie de son commentaire à l’explication des tournures de langue irrégulières que présente le texte de Virgile. S’il excuse ces irrégularités en raison du langage poétique ou de l’antiquité du texte, le grammairien en proscrit toutefois l’usage à ses étudiants. La reconnaissance de l’autorité du texte entretient alors une tension constante avec les règles synthétiques qu’a établies la discipline grammaticale.
Cette recherche se propose d’explorer d’abord cette tension sous deux aspects précis : le traitement de la syntaxe des prépositions et le déploiement du langage technique définissant les différentes expressions jugées irrégulières. Pour comprendre de quelle manière langage constitue aux yeux du grammairien le socle du savoir objectif sur le monde antique, un troisième chapitre est consacré à l’apport notionnel et pédagogique des étymologies savantes pour le commentaire. Servius est héritier d’une longue tradition intellectuelle, ce qu’il ne rend pas toujours apparent dans ses notices. Cette recherche s’est fait un souci de déterminer l’origine de principes sur lesquels s’appuie la composition des scholies serviennes.In the 4th century, Roman grammarian Maurus Servius Honoratus composed his
commentary on Virgil's Aeneid. One of the aims of this collection of commentaries, or
scholia, was to teach a normative language guided by the principles of latinitas: Latin in
accordance with grammatical principles. Despite the Aeneid's long-standing centrality in
Latin education and culture, Servius devotes much of his commentary to explaining the
irregular turns of language in Virgil's text. Although he excuses these irregularities on the
grounds of poetic language or the antiquity of the text, the grammarian nonetheless forbids
their use by his students. Recognition of the text's authority thus maintains a constant
tension with the synthetic rules established by the discipline of grammar.
This research will explore this tension from two specific angles: the syntactic
treatment of prepositions and the deployment of technical language to define various
expressions deemed irregular. To understand how the grammarian sees language as the
foundation of objective knowledge about the ancient world, a third chapter is devoted to
the notional and pedagogical contribution of learned etymologies to commentary. Servius
is heir to a long intellectual tradition, which he does not always make apparent in his notes.
The aim of this research is to determine the origin of some principles underlying the
composition of Servian scholia
A fractal approach to the clustering of earthquakes : applications to the seismicity of the New Hebrides
Low abundances of heavy elements in the solar outer layers: comparisons of solar models with helioseismic inversions
Recent solar photospheric abundance analyses have led to a significant
reduction of the metal abundances compared to the previous determinations. The
solar models computed with standard opacities and diffusion processes using
these new abundances give poor agreement with helioseismic inversions for the
sound-speed profile, the surface helium abundance, and the convective zone
depth.
We attempt to obtain a good agreement between helioseismic inversions and
solar models which present the "old" mixture in the interior and new chemical
composition in the convective zone. To reach this result, we assume an
undermetallic accretion at the beginning of the main sequence.
We compute solar models with the Toulouse-Geneva Evolution Code, in which we
simulate an undermetallic accretion in the early stages of the main sequence,
in order to obtain new mixture in the outer convective zone. We compare the
sound-speed profile, the convective zone depth, and the surface helium
abundance with those deduced from helioseismology.
The model with accretion but without any mixing process inside is in better
agreement with helioseismology than the solar model with the new abundances
throughout. There is, however, a spike under the convective zone which reaches
3.4%. Furthermore, the convective zone depth and the surface helium abundance
are too low. Introducing undershooting below the convective zone allows us to
recover the good convective zone radius and the addition of rotation-induced
mixing and tachocline allows us to reconcile the surface helium abundance. But
in any case the agreement of the sound-speed profile with helioseismic
inference is worse than obtained with the old abundances.Comment: 5 pages, 2 figure
Abundance anomalies in pre-main-sequence stars: Stellar evolution models with mass loss
The effects of atomic diffusion on internal and surface abundances of A and F
pre-main-sequence stars with mass loss are studied in order to determine at
what age the effects materialize, as well as to further understand the
processes at play in HAeBe and young ApBp stars. Self-consistent stellar
evolution models of 1.5 to 2.8Msun with atomic diffusion (including radiative
accelerations) for all species within the OPAL opacity database were computed
and compared to observations of HAeBe stars. Atomic diffusion in the presence
of weak mass loss can explain the observed abundance anomalies of
pre-main-sequence stars, as well as the presence of binary systems with metal
rich primaries and chemically normal secondaries such as V380 Ori and HD72106.
This is in contrast to turbulence models which do not allow for abundance
anomalies to develop on the pre-main-sequence. The age at which anomalies can
appear depends on stellar mass. For A and F stars, the effects of atomic
diffusion can modify both the internal and surface abundances before the onset
of the MS. The appearance of important surface abundance anomalies on the
pre-main-sequence does not require mass loss, though the mass loss rate affects
their amplitude. Observational tests are suggested to decipher the effects of
mass loss from those of turbulent mixing. If abundance anomalies are confirmed
in pre-main-sequence stars they would severely limit the role of turbulence in
these stars.Comment: 9 pages, 6 figures, accepeted for publicatio
Ketamine Infusions For Post-Cesarean Pain In Patients with Opioid Use Disorder
Discussion:
• Opioid consumption may be reduced during ketamine infusion without significant side effects
• Further investigation planned with a prospective, randomized, double-blind, placebo-controlled trial.https://knowledgeconnection.mainehealth.org/lambrew-retreat-2021/1026/thumbnail.jp
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