7,995 research outputs found

    THE LOCATIONAL DETERMINANTS OF WESTERN NONMETRO HIGH TECH MANUFACTURERS: AN ECONOMETRIC ANALYSIS

    Get PDF
    The Tobit estimation procedure was used to determine the factors which influence the location and size of high technology manufacturers in nonmetro areas in the West. The results indicate that high tech branch plants tend to locate in populous counties adjacent to Metropolitan Statistical Areas (MSAs). Percent of local employment in manufacturing and agriculture was inversely related to branch plant employment, and the stock of human capital was not significantly related to employment. High tech unit plants also exhibited a propensity to locate in the more populous counties. Unlike branch plants, the unit concerns were more likely to develop or locate in communities with a highly educated work force and at greater distances from metro areas. The unit plants better fit the perception of high tech plants selecting high amenity locations with abundant skilled labor.Industrial Organization, Labor and Human Capital,

    Estimating the Knowledge-Capital Model of the Multinational Enterprise

    Get PDF
    What we term the firm includes three principal assumptions. First, services of knowledge-based and knowledge-generating activities, such as R&D, can be geographically separated from production and supplied to production facilities at low cost. Second, these knowledge-intensive activities are skilled-labor intensive relative to production. These characteristics give rise to vertical multinationals, which fragment production and locate activities according to factor prices and market size. Third, knowledge-based services have a (partial) joint-input characteristic that they can be supplied to additional production facilities at low cost. This characteristic gives rise to horizontal multinationals, which produce the same goods or services in multiple locations. In this paper, we note how this model predicts relationships between affiliate sales and country characteristics. We then subject these predictions to empirical tests.

    Evolutionary Divergence in Developmental Strategies and Neuromodulatory Control Systems of Two Amphibian Locomotor Networks

    Get PDF
    Attempts to understand the neural mechanisms which produce behaviour must consider both prevailing sensory cues and the central cellular and synaptic changes they direct. At each level, neuromodulation can additionally shape the final output. We have investigated neuromodulation in the developing spinal motor networks in hatchling tadpoles of two closely related amphibians, Xenopus laevis and Rana temporaria to examine the subtle differences in their behaviours that could be attributed to their evolutionary divergence. At the point of hatching, both species can swim in response to a mechanosensory stimulus, however Rana embryos often display a more forceful, non-locomotory coiling behaviour. Whilst the synaptic drive that underlies these behaviours appears similar, subtle inter-specific differences in neuronal properties shape motor outputs in different ways. For example, Rana neurons express N-methyl-D-aspartate (NMDA)/serotonin (5-HT)-dependent oscillations, not present in hatchling Xenopus and many also exhibit a prominent slow spike after-hyperpolarisation. Such properties may endow the spinal circuitry of Rana with the ability to produce a more flexible range of outputs. Finally, we compare the roles of the neuromodulators 5-HT, noradrenaline (NA) and nitric oxide (NO) in shaping motor outputs. 5-HT increases burst durations during swimming in both Xenopus and Rana, but 5-HT dramatically slows the cycle period in Rana with little effect in Xenopus. Three distinct, but presumably homologous NO-containing brainstem clusters of neurons have been described, yet the effects of NO differ between species. In Xenopus, NO slows and shortens swimming in a manner similar to NA, yet in Rana NO and NA elicit the non-rhythmic coiling pattern

    Sociotechnical systems as applied to knowledge work

    Get PDF
    This study examines the logic behind choosing variances and the design of forums during the planning of deliberations in non-routine work environments using a Sociotechnical System design approach. This study was accomplished through review and comparison of literature on sociotechnical applications of non-routine, knowledge work environments. The traditional sociotechnical application applied to factory settings with linear and routine work tasks analyzes unit operations within an open system, identifying technical variances that contribute to problems and social roles that control the variances. A new sociotechnical approach has been developed for systems involved in non-routine, knowledge work environments. This approach focuses on deliberations formed around topics, establishes variances that lead to poor deliberations, designs forums that minimize variances and gives control of variances to discretionary coalitions. These results generally support that variances contributing to poor deliberations are well established and that organizations need only identify the key variances that contribute to problems in their system. Organizations need to understand how the key variances affect the development of knowledge and how forums can be designed to enhance deliberations. This study places specific focus on the design of information technology forums that enhance knowledge developmenthttp://www.archive.org/details/sociotechnicalsy00oswaLieutenant, United States NavyApproved for public release; distribution is unlimited

    Effects of Hydrogen on GRCop-84

    Get PDF
    This report is a section of the final report on the GRCop-84 task of the Constellation Program and incorporates the results obtained between October 2000 and September 2005 when the program ended. GRCop-84 contains approximately 5.5 wt% Nb. Nb can react with H and embrittle easily. Previous work had indicated the thermodynamic possibility that Cr 2 Nb could react with H and form niobium hydrides in the presence of high pressure H such as seen in the Space Shuttle Main Engine. In this study, samples were charged with H and then tested in both high pressure H and He environments to determine if measurable differences existed which indicate that hydrogen embrittlement occurs in GRCop-84. Tensile, notched tensile, stress rupture and low cycle fatigue properties were surveyed. High pressure H environment stress rupture testing resulted in a lower reduction in area than a high pressure He environment, and the LCF lives at high strain ranges fall below the lower 95 percent confidence interval for the baseline data, but in general no significant differences were noted either between H and He environment tests or between hydrogen charged materials and the baseline, uncharged extruded GRCop-84 data sets. There was also no discernable evidence of the formation of hydrides or changes in fracture morphology indicating hydrogen embrittlement occurred

    EC72-1529 Controlling Sorghum Greenbugs

    Get PDF
    Extension Circular 72-1539 discusses controlling sorghum greenbug

    Production of 21 Ne in depth-profiled olivine from a 54 Ma basalt sequence, Eastern Highlands (37° S), Australia

    Get PDF
    In this study we investigate the cosmogenic neon component in olivine samples from a vertical profile in order to quantify muogenic 21Ne production in this mineral. Samples were collected from an 11 m thick Eocene basalt profile in the Eastern Highlands of southeastern Australia. An eruption age of 54.15 ± 0.36 Ma (2σ) was determined from 40Ar/39Ar step-heating experiments (n = 6) on three whole-rock samples. A 36Cl profile on the section indicated an apparent steady state erosion rate of 4.7 ± 0.5 m Ma−1. The eruption age was used to calculate in situ produced radiogenic 4He and nucleogenic 3He and 21Ne concentrations in olivine. Olivine mineral separates (n = 4), extracted from the upper two metres of the studied profile, reveal cosmogenic 21Ne concentrations that attenuate exponentially with depth. However, olivine (Fo68) extracted from below 2 m does not contain discernible 21Ne aside from magmatic and nucleogenic components, with the exception of one sample that apparently contained equal proportions of nucleogenic and muogenic neon. Modelling results suggest a muogenic neon sea-level high-latitude production rate of 0.02 ± 0.04 to 0.9 ± 1.3 atoms g−1 a−1 (1σ), or <2.5% of spallogenic cosmogenic 21Ne production at Earth’s surface. These data support a key implicit assumption in the literature that accumulation of muogenic 21Ne in olivine in surface samples is likely to be negligible/minimal compared to spallogenic 21Ne

    The Preexisting Relationship Doctrine Under Regulation D: A Rule Without Reason?

    Full text link

    Cyclopropanation Catalyzed by Osmium Porphyrin Complexes

    Get PDF
    Cyclopropanation of alkenes can be accomplished catalytically2 or stoichiometrically.3 Catalytic systems typically use a diazo reagent as the carbene source and a metal-containing mediator which forms a postulated metal carbene intermediate. Transfer of the carbene fragment from the metal to an alkene produces the cyclopropane product. Despite the wide variety of catalytic cyclopropanation systems, the putative carbene complex has never been isolated or observed in a catalytic system. This is somewhat surprising since the second category of cyclopropanation reactions involves the stoichiometric reaction of isolated car bene complexes with an alkene to form a cyclopropane. None of the isolated carbene complexes show catalytic cyclopropanation activity. Several years ago Callot demonstrated that rhodium porphyrins catalytically cyclopropanated a variety of alkenes in the presence of ethyl diazoacetate.4 Kodadek and co-workers have expanded this work and have attempted to prepare synthetically useful enantioselective catalysts for the formation of cyclopropanes.5 Their approach has been to use rhodium complexes with optically active porphyrins to induce chirality into the product. A similar approach was used for a variety of non-porphyrin copper catalysts.6 Kodadek has shown that the carbon-bound diazonium complex [(TTP)RhC(H)(C02Et)(N2W is an intermediate in the catalytic cyclopropanation of styrene with ethyl diazoacetate.7•8 In addition, kinetic studies suggest that the formation of a rhodium carbene complex is at least partially rate limiting.8 However, this carbene complex has not been isolated or directly observed. We report herein the use of osmium porphyrins as stereoselective cyclopropanation catalysts using ethyl diazoacetate with a variety of alkenes. In addition, our studies show that an isolable carbene complex ((TTP)Os=CHC02Et) is capable of catalytically and stoichiometrically cyclopropanating styrene
    corecore