THE CONTRIBUTION OF RESEARCH TO U.S. SOYBEAN YIELDS

This study addresses several questions: (1) is a soybean yield limit being reached?, (2) what is the rate of return to soybean research, and is the research effect stable over time?, (3) are technology spill-overs between states important?, (4) do input and output price fluctuations affect soybean yields?, (5) what types of weather affect soybean yields?Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Elevated temperature tension, compression and creep-rupture behavior of (001)-oriented single crystal superalloy PWA 1480

Tensile and compressive flow behavior at various temperatures and strain rates, and tensile creep rupture behavior at 850 and 1050 C and various stresses were studied for (001)-oriented single crystals of the Ni-base superalloy PWA 1480. At temperatures up to 760 C, the flow stress is insensitive to strain rate and of greater magnitude in tension than in compression. At temperatures of 800 C and above, the flow stress decreases continuously with decreasing strain rate and the tension/compression anisotropy diminishes. The second stage creep rate and rupture time exhibited power law relationships with the applied stress for both 850 and 1050 C, however with different stress dependencies. The stress exponent for the steady state creep rate was about 7 at 1050 C, but much higher at 850 C, about 12. Directional coarsening of the gamma' phase occurred during creep at 1050 C, but not at 850 C

Creep-fatigue behavior of NiCoCrAlY coated PWA 1480 superalloy single crystals

Single crystal specimens of a Ni base superalloy, PWA 1480, with a low pressure plasma sprayed NiCoCrAlY coating were tested in various 0.1 Hz fatigue and creep fatigue cycles both at 1015 and 1050 C. Creep fatigue tests of the cp, pc, and cc types were conducted with various constant total strain ranges employing creep dwells at various constant stresses. Considerable cyclic softening occurred as was evidenced particularly by rapidly increasing creep rates in the creep fatigue tests. The cycle time in the creep fatigue tests typically decreased by more than 80 percent at 0.5 N sub f. Though cyclic life did correlate with delta epsilon sub in a better correlation existed with sub f for both the fatigue and creep fatigue tests, and poor correlations were observed with either sigma sub max or the average cycle time. A model containing both delta sigma and delta sigma (sub in), N sub f = alpha delta sigma (sub in) beta delta sigma gamma, with best fit values of sigma for each cycle type, but the same values of beta and gamam, was found to provide good correlations. Life lines were not greatly different among the cycle types, differing only by a factor of about three. The cp cycle life line was lowest for both test temperatures, however among the other three cycle types there was no consistent ranking. For all test types failure occurred predominately by multiple internal cracking originating at pores. The strong correlation of life with delta sigma may reflect a significant crack growth period in the life of the specimens

Thermomechanical deformation behavior of a dynamic strain aging alloy, Hastelloy X

An experimental study was performed to identify the effects of dynamic strain aging (solute drag) and metallurgical instabilities under thermomechanical loading conditions. The study involved a series of closely controlled thermomechanical deformation tests on the solid-solution-strenghened nickel-base superalloy, Hastelloy X. This alloy exhibits a strong isothermal strain aging peak at approximately 600 C, promoted by the effects of solute drag and precipitation hardening. Macroscopic thermomechanical hardening trends are correlated with microstructural characteristics through the use of transmission electron microscopy. These observations are compared and contrasted with isothermal conditions. Thermomechanical behavior unique to the isothermal database is identified and discussed. The microstructural characteristics were shown to be dominated by effects associated with the highest temperature of the thermomechanical cycle. Results indicate that the deformation behavior of Hastelloy X is thermomechanically path dependent. In addition, guidance is given pertaining to deformation modeling in the context of macroscopic unified theory. An internal state variable is formulated to qualitatively reflect the isotropic hardening trends identified in the TMD experiments

Aircraft aerodynamic prediction method for V/STOL transition including flow separation

A numerical procedure was developed for the aerodynamic force and moment analysis of V/STOL aircraft operating in the transition regime between hover and conventional forward flight. The trajectories, cross sectional area variations, and mass entrainment rates of the jets are calculated by the Adler-Baron Jet-in-Crossflow Program. The inviscid effects of the interaction between the jets and airframe on the aerodynamic properties are determined by use of the MCAIR 3-D Subsonic properties are determined by use of the MCAIR 3-D Subsonic Potential Flow Program, a surface panel method. In addition, the MCAIR 3-D Geometry influence Coefficient Program is used to calculate a matrix of partial derivatives that represent the rate of change of the inviscid aerodynamic properties with respect to arbitrary changes in the effective wing shape

Emerging radiopharmaceuticals for PET-imaging gliomas. A multi-: radiopharmaceutical, camera, modality, model, and modelling assessment

Gliomas, which are a type of brain tumour derived from the non-neuronal and nutrient-supplying glial cells of the brain, are particularly devastating disease due to the importance and delicate nature of cerebral matter. Surgical removal, chemotherapy, and radiation therapy often have unwanted consequences depending on a variety of physiological and probability factors. With the human life expectancy averaging 12-15 months after clinical diagnosis (with treatment) for aggressive brain tumours, accurately detecting and characterizing these tumours non-invasively is important for treatment planning. Currently, the highest anatomical resolution imaging modality available for brain imaging is magnetic resonance imaging (MRI), but this lacks biochemical information. Positron emission tomography paired with computed tomography for anatomical reference (PET-CT) divulges quantifiable biochemical information. By selecting imaging radiopharmaceuticals for PET imaging that have relevance to tumour surface proteins or other cellular metabolic processes it is possible to not only aid in detecting or delineating gliomas, but also gain specific biochemical-property insight into these lesions. The aim of these studies was to evaluate the two emerging radiopharmaceuticals (2S, 4R)-4-[18F]fluoroglutamine ([18F]FGln) and Al[18F]F-NOTA-Folate ([18F]FOL) and to directly compare them with routinely clinically-used radiopharmaceuticals 2-deoxy-2-[18F]fluoro-ᴅ-glucose ([18F]FDG) and ʟ-[11C]methionine ([11C]Met) for the PET imaging of gliomas in animal models. Other parameters, such as the in vivo stability, ex vivo biodistribution, in vitro binding and blocking, and the presence of relevant receptors on human tissue samples were investigated in to divulge additional information. The results demonstrated that both [18F]FGln and [18F]FOL provided an enhanced level of contrast between tumour and adjacent non-tumour brain tissue versus that of the clinically used radiopharmaceuticals [18F]FDG and [11C]Met in animal models.Uudet radiolääkeaineet glioomien PET-kuvantamiseen. Tutkimuksia radiolääkeaineista, modaliteeteista, kameroista, kokeellisista malleista ja mallintamisesta Glioomat ovat aivokasvaimia, jotka syntyvät ravinteiden kuljetusta hoitavista glia- eli hermotukisoluista. Ne ovat erityisen tuhoisia sairauksia aivokudoksen tärkeyden ja herkkyyden vuoksi. Kirurgisella leikkauksella, kemoterapialla, ja sädehoidolla on usein ei-toivottuja seurauksia riippuen fysiologisista ja todennäköisyystekijöistä. Koska elinajanodote aggressiivisen aivokasvaimen diagnoosin jälkeen on keskimäärin 12–15 kuukautta (hoidon kanssa), ei-invasiivinen tarkka havaitseminen ja karakterisointi on tärkeää hoidon suunnittelussa. Tällä hetkellä parhaat työkalut aivojen kuvantamiseen ovat magneettikuvaus (MRI), joka mahdollistaa parhaimman anatomisen tarkkuuden, ja positroniemissiotomografia (PET), joka paljastaa biokemiallisen informaation. Valitsemalle PET-kuvantamiseen radiolääkeaine, joka kiinnittyy syöpäsolun pintaproteiineihin tai liittyy solun aineenvaihduntaprosessiin on mahdollista paitsi havaita tai rajata glioomia, myös saada erityistä biokemiallista tietoa näistä leesioista. Tämän tutkimuksen tavoitteena oli arvioida kahta uutta radiolääkeainetta; (2S, 4R)-4-[18F]fluoriglutamiinia ([18F]FGln) ja Al[18F]F-NOTA-folaattia ([18F]FOL) ja verrata niitä kliinisessä käytössä oleviin 2-deoxy-2-[18F]fluori-ᴅ-glukoosiin ([18F]FDG) ja ʟ-[11C]metioniiniin ([11C]Met) glioomien PET-kuvantamisessa. Stabiilisuutta, biologista jakautumista, sitoutumista ja sitoutumisen salpautumista, sekä farmakokineettista mallintamista tutkittiin in vivo, ex vivo ja in vitro olosuhteissa eläinmalleissa ja kudosnäytteillä. Tulokset osoittivat, että eläinmalleissa sekä [18F]FGln että [18F]FOL mahdollistavat paremman kontrastin tuumorin ja viereisen tuumorittoman aivokudoksen välillä verrattuna kliinisessä käytössä oleviin [18F]FDG ja [11C]Met radiolääkeaineisiin

THE CONTRIBUTION OF TECHNOLOGY TO SOYBEAN YIELDS IN MINNESOTA

Crop Production/Industries,

Interactive Influence of Turbidity and Light on Larval Bluegill (Lepomis macrochirus) Foraging

Abstract in English and French.In a series of in situ enclosure experiments with larval bluegill (lepomis macrochirus), we demonstrate that turbidity from suspended sediments reduces bluegill consumption of crustacean zooplankton, primarily cyclopoid copepods and cogepod nauplii. However, this reduction occurred only when light intensity in parts of enclosures fell below a threshold, estimated at <450 lx. Following recent studies demonstrating copepod die1 vertical migration in response to predators, it appears that copepods in our experiments used low-light strata as a refuge. Without this apparent refuge present, larval bluegill consumption increased with increasing turbidity, but prey were smaller on average. Thus, prey biomass consumed by larval bluegill did not differ with turbidity in high-light conditions. We postulate that the shift to smaller prey across taxa at higher turbidity, when light intensity exceeded 450 lx, derives from increased prey-background contrast. In low-light conditions, larval bluegill consumed larger, but fewer, zooplankton with increasing turbidity, resulting in lower prey biomass consumed. Thus, we demonstrate the field conditions causing negative turbidity effects on larval fish foraging success, and thus growth and recruitment.This research was supported in part by National Science Foundation grants BSR-8715730 and BSR-9107173 to R. A. Stein and Sigma Xi Grants-in-Aid-of-Research to J. G. Miner

New nickel-base wrought superalloy with applications up to 1253 K (1800 F)

Alloy possesses combination of high tensile strength at low and intermediate temperatures to 1033 K with good rupture strength at high temperatures to 1255 K. Alloy has promise for turbine disk application in future gas turbine engines and for wrought integrally bladed turbine wheel; thickness and weight of disk portion of wheel could be reduced

Infrared radiometry experiment for Mariner Mars 1971

The infrared radiometer is designed to provide brightness temperatures of the surface of Mars by measuring the energy radiated in the 8 to 12 and 18 to 25 μ wavelength bands. The instrument is essentially the same as that flown on the Mariner Mars 1969 missions, modified only to define more sharply the field of view. Because Mariner Mars 1971 will orbit Mars, a given area of the planet will be observed at a variety of local times, and the characterization of the various areas by their thermophysical properties will be more complete than that obtained by Mariner Mars 1969