Residual Action of Slow Release Systemic Insecticides on \u3ci\u3eRhopalosiphum Padi\u3c/i\u3e (Homoptera: Aphididae) on Wheat

Slow release formulations of acephate and carbofuran encapsulated in pearl corn­ starch or corn flour granules were applied to the soil at seeding time of potted \u27Caldwell\u27 wheat in the laboratory. Dosages of these insecticides were adjusted to a standard of IO kg/ha of a 10 10 granular formulation of carbofuran. The residual action of these insecticide treatments against Rhopalosiphum padi were compared with those obtained with that of carbofuran 150 at corresponding dosages and foliar sprays of solutions of acephate (25 10 EC) at 0.2 10 and carbofuran (4F) at 1.25 10, applied 12 d after seedling emergence. The residual action of carbofuran 150, which controlled R. padi since seedling emergence, lasted 28.5 d. The slow release granular formulations of carbofuran began to provide control (\u3e 50 10 aphid mortality) on days 13.3 and 17.9 after seeding. They controlled the insect until days 31.6 and 35.5 after seeding. The two corresponding granular formulations of acephate began to provide control on days 15.0 and 17.0 after seeding and con­ trolled the aphids until days 31.5 and 32.8 after seeding. The foliar sprays of acephate and carbofuran provided control for 18.3 and 36.2 d from application, respectively. The slow release granular formulations provided control of R. padi, an important vector of barley yellow dwarf virus, during early. stages of wheat development

Physics case of the very high energy electron--proton collider, VHEeP

The possibility of a very high energy electron-proton (VHEeP) collider with a centre-of-mass energy of 9 TeV has been presented at previous workshops. These proceedings briefly summarise the VHEeP concept, which was recently published, and developments since then, as well as future directions. At the VHEeP collider, with a centre-of-mass energy 30 times greater than HERA, parton momentum fractions, $x$, down to about $10^{-8}$ are accessible for photon virtualities, $Q^2$, of 1 GeV$^2$. This extension in the kinematic range to low $x$ complements proposals for other electron-proton or electron-ion colliders.Comment: 6 pages, 2 figures, for proceedings of DIS 2017 worksho

Elasticity of risk aversion and international trade

This note analyzes export production in the presence of exchange rate uncertainty under mean-variance preferences. We present the elasticity of risk aversion, since this elasticity concept permits a distinct investigation of risk and expectation effects on exports. Counterintutitive results are possible, e.g. though the home currency is revaluating (devaluating) exports of the firm increase (decrease). This fact may contribute to the explanation of disturbing empirical results.Exchange rate risk, trade, elasticity of risk aversion, meanvariance model, devaluation

Elasticity of risk aversion and international trade

This note analyzes export production in the presence of exchange rate uncertainty under mean-variance preferences. We present the elasticity of risk aversion, since this elasticity concept permits a distinct investigation of risk and expectation effects on exports. Counterintutitive results are possible, e.g. though the home currency is revaluating (devaluating) exports of the firm increase (decrease). This fact may contribute to the explanation of disturbing empirical results.Exchange rate risk, trade, elasticity of risk aversion, meanvariance model, devaluation

Physical activity in older adulthood

The present study investigated the function of physical activity in the lives of physically active older adults. The impact of aging stereotypes on physical activity was explored. Using a grounded theory analysis of interview data, positive outlook emerged as an integral link to leading a physically active lifestyle in older adulthood. Positive outlook was comprised of five major components: being open to possibilities, exercising control of aspects of one\u27s life, feeling youthful, satisfaction and feeling fortunate, and having a purpose in life. This constellation of components interacts with one another and good health to influence the importance of physical activity in one\u27s life and, in turn, one\u27s resistance to aging stereotypes. The perspective of participants is reflected in a theoretical model that accounts for their behaviour

Synthesis of a Molecular Charm Bracelet via Click Cyclization and Olefin Metathesis Clipping

We describe the synthesis of a polycatenated cyclic polymer, a structure that resembles a molecular charm bracelet. Ruthenium-catalyzed ring-opening metathesis polymerization of an aminocontaining cyclic olefin monomer in the presence of a chain transfer agent generated an α,ω-diazide functionalized polyamine. Cyclization of the resulting linear polyamine using pseudo-high-dilution coppercatalyzed click cyclization produced a cyclic polymer in 19% yield. The click reaction was then further employed to remove linear contaminants from the cyclic polymer using azide- and alkyne-functionalized scavenging resins, and the purified cyclic polymer product was characterized by gel permeation chromatography, ^1H NMR spectroscopy, and IR spectroscopy. Polymer hydrogenation and conversion to the corresponding polyammonium species enabled coordination and interlocking of diolefin polyether fragments around the cyclic polymer backbone using ruthenium-catalyzed ring-closing olefin metathesis to afford a molecular charm bracelet structure. This charm bracelet complex was characterized by ^1H NMR spectroscopy, and the catenated nature of the small rings was confirmed using two-dimensional diffusion-ordered NMR spectroscopy