591 research outputs found

    Two Trapping Systems to Determine Incidence and Duration of Migration of Adult Alfalfa Weevils, \u3ci\u3eHypera Postica\u3c/i\u3e (Coleoptera: Curculionidae)

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    Emergence and flight traps were used to study the pre- and post-diapause movements of the alfalfa weevil, Hypera postica. The emergence traps proved to be an excellent tool in determining the time of diapause termination and in providing an accurate accounting of the number of weevils per unit area in aestivation sites. The flight traps showed when diapause flights to and from alfalfa fields took place. Both trapping systems can be utilized in a pest control program to locate more closely where the alfalfa weevil aestivates and when diapause related movements occur

    Fall Termination of Aestivation and Field Dispersal of the Alfalfa Weevil (Coleoptera: Curculionidae) in Illinois

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    Emergence traps, flight traps, sweeping, and egg sampling were employed to determine fall termination of aestivation of the alfalfa weevil, Hypera postica, and patterns and timing of field reentry, and subsequent fall oviposition. Adult alfalfa weevils were found to terminate aestivation in wood edge field borders in mid-late October. Field reentry began in late October as a gradual process, starting at wooded field borders, with the field population equally dispersed by mid-November

    Effect on Constant Versus Fluctuating Temperature Regimes on \u3ci\u3eBathyplectes Curculionis\u3c/i\u3e (Hymenoptera: Ichneumonidae) Activity

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    Individual female Bathyplectes curculionis parasites were exposed to either a series of constant or fluctuating temperature regimes and supplied with a new group of host Hypera postica larvae every day. The fluctuating temperatures were calculated from an average of weekly air temperatures during a period of actual field oviposition by the parasite. The rearing of adult parasites under a constant versus fluctuating temperature regime resulted in no significant difference in parasitism, longevity, or fecundity. The threshold for B. curculionis activity was estimated to be 6-8°C

    First-order wedge wetting revisited

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    We consider a fluid adsorbed in a wedge made from was that exhibit a first-order wetting transition and revisit the argument as to why and how the pre-filling and pre-wetting coexistence lines merge when the opening angle is increased approaching the planar geometry. We clarify the nature of the possible surface phase diagrams, pointing out the connection with complete pre-wetting, and show that the merging of the coexistence lines lead to new interfacial transitions. These occur along the side was and are associated with the unbinding of the thin-thick interface, rather than the liquid-gas interface (meniscus), from the wedge apex. When fluctuation effects, together with the influence of dispersion forces are included, these transitions display strong non-universal critical singularities that depend on the opening angle itself. Similar phenomena are also shown to occur for adsorption near an apex tip.This work was partly funded by the EPSRC UK grant EP/L020564/1, "Multiscale Analysis of Complex Interfacial Phenomena". C.R. also acknowledges the support of the grant FIS2015-66523-P (MINECO/FEDER, UE)

    Current density functional framework for spin–orbit coupling

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    Relativistic two-component density functional calculations are carried out in a non-collinear formalism to describe spin–orbit interactions, where the exchange–correlation functional is constructed as a generalization of the non-relativistic density functional approximation. Contrary to non-relativistic density functional theory (DFT), spin–orbit coupling, however, leads to a non-vanishing paramagnetic current density. Density functionals depending on the kinetic energy density, such as meta-generalized gradient approximations, should therefore be constructed in the framework of current DFT (CDFT). The latter has previously exclusively been used in the regime of strong magnetic fields. Herein, we present a consistent CDFT approach for relativistic DFT, including spin–orbit coupling. Furthermore, we assess the importance of the current density terms for ground-state energies, excitation energies, nuclear magnetic resonance shielding, and spin–spin coupling constants, as well as hyperfine coupling constants, Δ\Deltag-shifts, and the nuclear quadrupole interaction tensor in electron paramagnetic resonance (EPR) spectroscopy. The most notable changes are found for EPR properties. The impact of the current-dependent terms rises with the number of unpaired electrons, and consequently, the EPR properties are more sensitive toward CDFT. Considerable changes are observed for the strongly constrained and appropriately normed functionals, as well as the B97M family and TASK. The current density terms are less important when exact exchange is incorporated. At the same time, the current-dependent kernel ensures the stability of response calculations in all cases. We, therefore, strongly recommend to use the framework of CDFT for self-consistent spin–orbit calculations

    Reinigung und funktionelle Charakterisierung eines rekombinanten Maus-TNF-Inhibitors

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    TNF und seine Rezeptoren p75TNFR und p55TNFR spielen im Rahmen von EntzĂĽndungen und Autoimmunerkrankungen eine zentrale Rolle. Eine gezielte Hemmung von TNF wird bei Autoimmunerkrankungen, wie z.B. rheumatoider Arthritis eingesetzt. In der Arbeit wurde ein rekombinanter TNF-Inhibitor hergestellt, sowie dessen Struktur und biologische Wirksamkeit untersucht

    Restoring betatron phase coherence in a beam-loaded laser-wakefield accelerator

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    Matched beam loading in laser wakefield acceleration (LWFA), characterizing the state of flattening of the acceleration electric field along the bunch, leads to the minimization of energy spread at high bunch charges. Here, we demonstrate by independently controlling injected charge and acceleration gradients, using the self-truncated ionization injection scheme, that minimal energy spread coincides with a reduction of the normalized beam divergence. With the simultaneous confirmation of a constant beam radius at the plasma exit, deduced from betatron radiation spectroscopy, we attribute this effect to the reduction of chromatic betatron decoherence. Thus, beam loaded LWFA enables highest longitudinal and transverse phase space densities
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