217 research outputs found

    Significant Factors Influencing the Quality and Success of Supervised Farming Programs of Vocational Agriculture Students in Seven Schools of East Tennessee

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    (From the Introduction) This is a study of significant factors influencing the quality and success of supervised farming programs of vocational agricultural students in seven schools of East Tennessee. This study embodies the elements of the home, farm and school planning

    Control of biodegradation of a Mg alloy in simulated body fluid

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    Mg alloy AZ31 is an attractive candidate for coronary artery stents, as it possesses excellent biocompatibility in human body and good mechanical properties. However, AZ31 magnesium alloys generally have poor corrosion resistance in the body environment. This paper reports on the early stages of an investigation into the corrosion mechanism and the morphology of corrosion of AZ31 in simulated body fluid (SBF). The investigation will also consider ways of improving corrosion resistance of this alloy in SBF through the use of ionic liquids. The results to date have shown that AZ31 suffers severe localized pitting corrosion in SBF. The pits mainly develop adjacent to the Al-Mn intermetallic second phase in the α matrix. Energy Dispersive X-Ray Spectroscopy results revealed the presence of Mg, O, Ca, and P in the layer of corrosion product. Treatment of the AZ31 alloy prior to corrosion testing in SBF with the ionic liquid trimethyl (butyl) phosphonium diphenyl phosphate (P1444DPP) produced some increase in the corrosion resistance of the alloy

    Prospectus, November 23, 1976

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    TRUSTEES MEET: 25% TUITION INCREASE VOTED BY BOARD, NEW HOUR TOTAL $17; PC news in brief: Redford stars in \u27Jeremiah Johnson\u27, Spring Schedule changed, Sociological film today, See Chicago Bulls Nov. 30; Till Nov. 30th: Preregister now; \u27Disaster bus\u27 being fixed, should be ready by Jan.; Persecutor\u27s life changed; Illinois low in educ. support; Onarga application approved; 28% late on stud. loans; Before finals: Withdraw by December 15th; GI Bill: New vet allowances announced; Sign up now to save courses for later; Campus competition: Gunki heads stud. recognition; Library stairs sculpture just hanging around for 2 years; Theta Epsilon meets Dec. 1; Senior university: Sangamon State rep visits today; Care and cooking: There\u27s more to wild game than just hunting it; Flipping the bird...a collection of turkey recipes: First, the real one; Then, some recipes by for turkeys...: ...figure five pounds per person, ...I forgot to say to take the turkey out of the bag, ...watch the expressions of delight as they eat it; Timeless marital problems looked at in Coward play; Artist-in-residence: Wayne Forbes: showing need for people to care; Santa Claus arrives Friday; Theta Epsilon Frat. officers announced; Community Cultural Series: Twain Amer. Humor superb; Fifth Column: False Promises of entertainment; Classifieds; Cobra\u27s Corner: 3 candidates for center: Betka is \u27all-business\u27 vying for starting position; Bears still 1st, \u27Excess\u27 within 3 points; Schedule changed: Cagers open tonite at DuPage; Parkland Basketball Roster; Cobra captains ready; Decker wins final Freddy; Lockers must be renewed; Parkland College 1976-1977 Basketball Schedule; Women\u27s Basketball Schedulehttps://spark.parkland.edu/prospectus_1976/1002/thumbnail.jp

    Dual function of rare earth carboxylate compounds on the barrier properties and active corrosion inhibition of epoxy coatings on mild steel

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    In this work, two rare earth carboxylate compounds, lanthanum 4-hydroxycinnamate (La(4-OHcin)3) and yttrium 3-(4-methylbenzoyl)propanoate (Y(mbp)3), were incorporated into bisphenol-based epoxy resin to investigate their effectiveness in coating barrier properties and active corrosion inhibition. EIS results showed that the incorporation of rare earth carboxylate inhibitors significantly improved corrosion resistance compared to the inhibitor free coating, with the global impedance modulus remaining at a level higher than 1 GΩ cm2 after 219 days immersion. Following EIS experiments, cross-sectional views of the coatings exhibited a pore-plugging behavior by rare earth containing precipitates, which reinforced the coating barrier properties and delayed the electrolyte diffusion process. These effects were also reflected from the electrochemical parameters extracted from breakpoint frequency analysis and equivalent circuit modelling. Filiform corrosion experiments for artificially scratched coatings suggest that the addition of rare earth carboxylates effectively suppressed the initiation and growth of filaments as well as the development of the coating delamination front. The active corrosion inhibition is possibly related to the formation of a surface protective film consisting of bimetallic complexes and rare earth metal rich precipitates. The electrochemical measurements and surface analyses evidence the dual function of rare earth carboxylate species for enhancing coating barrier properties against electrolyte penetration and providing active corrosion inhibition for the underlying AS1020 mild steel

    Plant volatile-mediated signalling and its application in agriculture: successes and challenges

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    The mediation of volatile secondary metabolites in signalling between plants and other organisms has long been seen as presenting opportunities for sustainable crop protection. Initially, exploitation of interactions between plants and other organisms, particularly insect pests, foundered because of difficulties in delivering, sustainably, the signal systems for crop protection. We now have mounting and, in some cases, clear practical evidence for successful delivery by companion cropping or next-generation genetic modification (GM). At the same time, the type of plant signalling being exploited has expanded to signalling from plants to organisms antagonistic to pests, and to plant stress-induced, or primed, plant-to-plant signalling for defence and growth stimulation

    Juvenile Hormone (JH) Esterase of the Mosquito Culex quinquefasciatus Is Not a Target of the JH Analog Insecticide Methoprene

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    Juvenile hormones (JHs) are essential sesquiterpenes that control insect development and reproduction. JH analog (JHA) insecticides such as methoprene are compounds that mimic the structure and/or biological activity of JH. In this study we obtained a full-length cDNA, cqjhe, from the southern house mosquito Culex quinquefasciatus that encodes CqJHE, an esterase that selectively metabolizes JH. Unlike other recombinant esterases that have been identified from dipteran insects, CqJHE hydrolyzed JH with specificity constant (kcat/KM ratio) and Vmax values that are common among JH esterases (JHEs). CqJHE showed picomolar sensitivity to OTFP, a JHE-selective inhibitor, but more than 1000-fold lower sensitivity to DFP, a general esterase inhibitor. To our surprise, CqJHE did not metabolize the isopropyl ester of methoprene even when 25 pmol of methoprene was incubated with an amount of CqJHE that was sufficient to hydrolyze 7,200 pmol of JH to JH acid under the same assay conditions. In competition assays in which both JH and methoprene were available to CqJHE, methoprene did not show any inhibitory effects on the JH hydrolysis rate even when methoprene was present in the assay at a 10-fold higher concentration relative to JH. Our findings indicated that JHE is not a molecular target of methoprene. Our findings also do not support the hypothesis that methoprene functions in part by inhibiting the action of JHE

    The Astropy Problem

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    The Astropy Project (http://astropy.org) is, in its own words, "a community effort to develop a single core package for Astronomy in Python and foster interoperability between Python astronomy packages." For five years this project has been managed, written, and operated as a grassroots, self-organized, almost entirely volunteer effort while the software is used by the majority of the astronomical community. Despite this, the project has always been and remains to this day effectively unfunded. Further, contributors receive little or no formal recognition for creating and supporting what is now critical software. This paper explores the problem in detail, outlines possible solutions to correct this, and presents a few suggestions on how to address the sustainability of general purpose astronomical software
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