12,015 research outputs found
New records of ichneumon wasps (Hymenoptera, Ichneumonidae) from Malta
Recently some Maltese Hymenoptera were donated to the Hungarian Natural History Museum
(HNHM) and some other material was sent to the Natural History Museum in London (BMNH)
for identification by the second author. Amongst these specimens were six ichneumon wasp species
new to the fauna of Malta.
Ichneumonidae taxonomy and nomenclature follow Yu et al. (2012), and host records were
traced through this resource. Identifications were based on keys provided by Szépligeti (1905),
Schmiedeknecht (1909), BajĂĄri (1960), Townes et al. (1965), BajĂĄri & MĂłczĂĄr (1969), Townes
(1969; 1970a; 1970b; 1971), Horstmann (1976), Gauld & Mitchell (1977), Fitton et al. (1988),
Wahl (1993), and Tolkanitz (2007). The voucher specimens are deposited in the Hymenoptera
Collection of HNHM, Budapest, Hungary (those indicated by a HNHM id. number below), and
some duplicate specimens in D. Mifsudâs private insect collection (CDM) in Malta.peer-reviewe
Charmonium Suppression by Comover Scattering in Pb+Pb Collisions
The first reports of and production from experiment NA50 at
the CERN SPS are compared to predictions based on a hadronic model of
charmonium suppression. Data on centrality dependence and total cross sections
are in good accord with these predictions.Comment: 9 pages, latex, 6 figures, epsf, figure added and text modified to
clarify result
Atomic hydrogen cleaning of GaSb(001) surfaces
We show that the (001) surface of GaSb can be cleaned efficiently by exposure to atomic hydrogen at substrate temperatures in the range 400â470 °C. This treatment removes carbon and oxygen contamination, leaving a clean, ordered surface with a symmetric (1 Ă 3) reconstruction after a total H2 dose of approximately 150 kL. An ordered but partially oxidized surface is generated during cleaning, and the removal of this residual oxide is the most difficult part of the process. Auger electron spectroscopy and low energy electron diffraction were used to monitor the chemical cleanliness and the ordering of the surface during the cleaning process, whereas high resolution electron energy loss spectroscopy was used to probe the electronic structure in the near-surface region. The results obtained indicates that this cleaning procedure leaves no residual electronic damage in the near-surface region of the Te-doped (n ~ 5 Ă 1017 cm â 3) samples of GaSb(001) studied
Discovering baryon-number violating neutralino decays at the LHC.
Recently there has been much interest in the use of single-jet mass and jet substructure to identify boosted particles decaying hadronically at the LHC. We develop these ideas to address the challenging case of a neutralino decaying to three quarks in models with baryonic violation of R parity. These decays have previously been found to be swamped by QCD backgrounds. We demonstrate for the first time that such a decay might be observed directly at the LHC with high significance, by exploiting characteristics of the scales at which its composite jet breaks up into subjets
Epitaxial growth and surface reconstruction of CrSb(0001)
Smooth CrSb(0001) films have been grown by molecular beam epitaxy on MnSb(0001) â GaAs(111) substrates. CrSb(0001) shows (2âŻĂâŻ2), triple domain (1âŻĂâŻ4) and (â3Ăâ3)R30° reconstructed surfaces as well as a (1âŻĂâŻ1) phase. The dependence of reconstruction on substrate temperature and incident fluxes is very similar to MnSb(0001)
Organopalladium catalyst on S-terminated GaAs(001)-(2Ă6) surface
Organopalladium molecules, such as Pd(CH3COO)2 ({Pd}), immobilized on the S-terminated GaAs(001), termed GaAsâSâ{Pd} have high catalytic activity and cycle durability in the MizorokiâHeck reaction. It is thought that the presence of GaâS bonds in the single atomic layer S-termination is essential for these catalytic properties despite the much higher thickness (~100 nm) of the {Pd} films. In this study, the authors demonstrate the retention of GaâS bonds in ultrathin GaAsâSâ{Pd} by using reflection high-energy electron diffraction and scanning tunneling microscopy (STM). The ultrathin GaAsâSâ{Pd} was prepared by using a vapor-deposition technique. Deposited {Pd} was observed as ~1 nm dotlike structures with STM. The adsorption rate of {Pd} was also investigated
Habitual accountability routines in the boardroom: How boards balance control and collaboration
open3siCorporate accountability is a complex chain of reporting that reaches from external stakeholders into the organizationâs management structure. The transition from external to internal accountability mechanisms primarily occurs at the board of directors. Yet outside of incentive mechanisms, we know surprisingly little about how internal actors (management) are held to account by the representatives of external shareholders (the board). This paper explores the process of accountability at this transition point by documenting the routines used by boards to hold the firmâs management to account. In so doing we develop our understanding of the important transition between internal and external firm accountability.embargoed_20190401Nicholson, Gavin; Pugliese, Amedeo; Bezemer, Pieter JanNicholson, Gavin; Pugliese, Amedeo; Bezemer, Pieter Ja
A perceived gap between invasive species research and stakeholder priorities
Information from research has an important role to play in shaping policy and management responses to biological invasions but concern has been raised that research focuses more on furthering knowledge than on delivering practical solutions. We collated 449 priority areas for science and management from 160 stakeholders including practitioners, researchers and policy makers or advisors working with invasive species, and then compared them to the topics of 789 papers published in eight journals over the same time period (2009â2010). Whilst research papers addressed most of the priority areas identified by stakeholders, there was a difference in geographic and biological scales between the two, with individual studies addressing multiple priority areas but focusing on specific species and locations. We hypothesise that this difference in focal scales, combined with a lack of literature relating directly to management, contributes to the perception that invasive species research is not sufficiently geared towards delivering practical solutions. By emphasising the practical applications of applied research, and ensuring that pure research is translated or synthesised so that the implications are better understood, both the management of invasive species and the theoretical science of invasion biology can be enhanced
Taylor-type rules and total factor productivity
This paper examines the impact of a persistent shock to the growth rate of total factor productivity in a New Keynesian model in which the central bank does not observe the shock. The authors then investigate the performance of alternative policy rules in such an incomplete information environment. While some rules perform better than others, the authors demonstrate that inflation is more stable after a persistent productivity shock when monetary policy targets the output growth rate (not the output gap) or the price-level path (not the inflation rate). Both the output growth and price-level path rules generate less volatility in output and inflation following a persistent productivity shock compared with the Taylor rule.Taylor's rule ; Productivity ; Industrial productivity
The monetary instrument matters
This paper revisits the debate over the money supply versus the interest rate as the instrument of monetary policy. Using a dynamic stochastic general equilibrium framework, the authors examine the effects of alternative monetary policy rules on inflation persistence, the information content of monetary data, and real variables. They show that inflation persistence and the variability of inflation relative to money growth depend on whether the central bank follows a money growth rule or an interest rate rule. With a money growth rule, inflation is not persistent and the price level is much more volatile than the money supply. Those counterfactual implications are eliminated by the use of interest rate rules whether prices are sticky or not. A central bank's use of interest rate rules, however, obscures the information content of monetary aggregates and also leads to subtle problems for econometricians trying to estimate money demand functions or to identify shocks to the trend and cycle components of the money stock.Monetary policy ; Money supply ; Interest rates
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