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

Analisis Pemanfaatan E-commerce sebagai Strategi Bisnis Jual Beli Emas terhadap Kepuasan Pelanggan

Pemanfaatan e-commerce sebagai strategi bisnis dimasa depan sangat ditentukan oleh kepuasan dan penerimaan website sebagai sarana Perusahaan memberikan informasi harga emas. Perusahaan mempunyai inovasi produk unggulan yang mampu bersaing dengan kompetitor dibidang transaksi jual beli emas. Penelitian ini dilakukan pada pelanggan toko emas yang telah menggunakan layanan transaksi yang dilakukan Perusahaan sebanyak 150 responden. Metode analisis data yang digunakan adalah Structural Equation Model (SEM) .Berdasarkan teori Technology Acceptance Model (TAM) terdapat ketiga variabel prediktor yang telah dikembangkan peneliti yaitu desain/fitur website, sumber daya Perusahaan dan kemampuan/ketrampilan berhubungan dengan kebermanfaatan dan kemudahan akses ditentukan dengan sikap dan niat terhadap kepuasan dan penerimaan website. Sedangkan yang mempunyai pengaruh positif adalah sumber daya Perusahaan terhadap manfaat, kemudahan akses terhadap manfaat, kemudahan akses terhadap sikap, kebermanfaatan terhadap niat dan niat terhadap kepuasan serta kebermanfaatan terhadap kepuasan dan penerimaan website. Dengan demikian sumber daya Perusahaan dan kemudahan akses sangat mempengaruhi manfaat yang dapat menguatkan niat pengguna untuk mencapai tingkat kepuasan pelanggan

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

Characterisation of Cryogenic Material Properties of 3D-Printed Superconducting Niobium using a 3D Lumped Element Microwave Cavity

We present an experimental characterisation of the electrical properties of 3D-printed Niobium. The study was performed by inserting a 3D-printed Nb post inside an Aluminium cylindrical cavity, forming a 3D lumped element re-entrant microwave cavity resonator. The resonator was cooled to temperatures below the critical temperature of Niobium (9.25K) and then Aluminium (1.2K), while measuring the quality factors of the electromagnetic resonances. This was then compared with finite element analysis of the cavity and a measurement of the same cavity with an Aluminium post of similar dimensions and frequency, to extract the surface resistance of the Niobium post. The 3D-printed Niobium exhibited a transition to the superconducting state at a similar temperature to the regular Niobium, as well as a surface resistance of $3.1\times10^{-4}$ $\Omega$. This value was comparable to many samples of traditionally machined Niobium previously studied without specialised surface treatment. Furthermore, this study demonstrates a simple new method for characterizing the material properties of a relatively small and geometrically simple sample of superconductor, which could be easily applied to other materials, particularly 3D-printed materials. Further research and development in additive manufacturing may see the application of 3D-printed Niobium in not only superconducting cavity designs, but in the innovative technology of the future.Comment: 5 pages, 4 figure

Identifying Cross-Sided Liquidity Externalities

__Abstract__ We study the relevance of the cross-sided externality between liquidity makers and takers from the two-sided market perspective. We use exogenous changes in the make/take fee structure, minimum tick-size and technological shocks for liquidity takers and makers, as experiments to identify cross-sided complementarities between liquidity makers and takers in the U.S. equity market. We find that the externality is on average positive, but it decreases with adverse selection. We quantify the economic significance of the externality by evaluating an exchange's revenue after a make/take fee change