936 research outputs found

    Loki, Io: New groundbased observations and a model describing the change from periodic overturn

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    Loki Patera is the most powerful volcano in the solar system. We have obtained measurements of Loki's 3.5 micron brightness from NASA's Infrared Telescope Facility (IRTF) and have witnessed a change from the periodic behavior previously noted. While Loki brightened by a factor of several every 540 days prior to 2001, from 2001 through 2004 Loki remained at a constant, medium brightness. We have constructed a quantitative model of Loki as a basaltic lava lake whose solidified crust overturns when it becomes buoyantly unstable. By altering the speed at which the overturn propagates across the patera, we can match our groundbased brightness data. In addition, we can match other data taken at other times and wavelengths. By slowing the propagation speed dramatically, we can match the observations from 2001-2004. This slowing may be due to a small change in volatile content in the magma

    Modular Porous Plate Sublimator /MPPS/ requires only water supply for coolant

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    Modular porous plate sublimators, provided for each location where heat must be dissipated, conserve the battery power of a space vehicle by eliminating the coolant pump. The sublimator requires only a water supply for coolant

    Diffusion bonding makes strong seal at flanged connector

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    Copper strip seals a high pressure fluid system connector so that it is insensitive to relaxation of the bolt loads. The copper strip is diffusion bonded to the surfaces of the connector flange by application of high pressure and temperature

    The Sandwich algorithm for spatial equilibrium analysis

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    Recent advances in mathematical programming techniques have made it possible to provide more realistic solutions to applied economic problems. Although mathematical programming techniques are widely used, the economic content of the solutions is often limited by the assumptions imposed by the algorithms available. This report is designed to demonstrate the increased flexibility which is currently available for the solution of a wide range of spatial economic problems. Transportation and transhipment models have been widely used in the analysis of the impact of policy changes on spatial activity, Borrell & Zwart [l]; Beck, Rathbun and Abbott [2]. One of the major shortcomings of such models has been an inability to model the impact of more flexible pricing policies on regional supply and demand, while maintaining the realistic non linearities which are associated with processing and transportation costs. In this paper a simplified version of the transhipment model developed by Borrell & Zwart [l] is modified to incorporate regional supply response while at the same time retaining complex processing and handling cost relationships. This report outlines the general form of the spatial equilibrium problem and some of the solution techniques available, in a format easily understood by readers not conversant with operational research techniques. Initially the problem is defined and solution methods used in the past are then briefly described. The advantages and disadvantages of these methods are outlined before showing how a relatively new solution technique may be able to improve both the scope and flexibility of the problems being solved

    Design Criteria for Zero Leakage Connectors for Launch Vehicles. Mathematical Model of Interface Sealing Phenomenon, Volume 2 Final Report

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    Mathematical model of interface sealing phenomenon in determining design criteria for zero leakage connectors for launch vehicle

    Relationships between pig birth weight and expression of the immediate early gene EGR-1 in umbilical cord Wharton's jelly

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    Citation: Morton, J. M., Rathbun, T., & Davis, D. L. (2016). Relationships between pig birth weight and expression of the immediate early gene EGR-1 in umbilical cord Wharton's jelly. Journal of Animal Science, 94, 149-149. doi:10.2527/msasas2016-317In humans the expression of EGR-1 in umbilical cord Wharton’s jelly has been related to birth weight. In umbilical cords of small for gestational age (SGA) babies the expression of EGR-1 is increased compared to normal weight contemporaries. Expression of EGR-1 appears to indicate prenatal programming resulting from growth restriction. It is known that SGA babies develop slower compared to normal sized babies and in many ways are comparable to small birth weight pigs. Therefore we investigated whether EGR-1 expression in pig umbilical cord Wharton’s jelly is related to birth and weaning weights. Fifty-seven umbilical cords were collected from 5 litters (PIC; 326 × 1050), along with birth and weaning weights. Wharton’s jelly tissue was snap frozen and stored (?80°C) until RNA was extracted (Trizol method), RNA quantity determined using the Nanodrop method and quality was evaluated with an Agilent Bioanalyzer. Quantitative PCR was used to determine expression of EGR-1 compared to 18S and the data converted to relative expression using RNA from newborn pig testis as a calibrator. Birth weight (P < 0.003) and wean weight at d 21 (P < 0.026) were correlated negatively with EGR-1 expression. Larger pigs had decreased expression of EGR-1 compared to smaller pigs. The umbilical cords from the 14 pigs with the lowest expression of EGR-1 (bottom quartile) included only one pig with a birth weight < 1.11 kg while the top quartile included 9 pigs weighing less than 1.11 kg at birth (P < 0.002, chi square). In response to rising global demands for pork, swine producers have increased litter sizes and this has resulted in more small pigs at birth. We have identified that pigs with a birth weight below 1.11 kg have increased mortality rates by weaning age (3–4 wk). These pigs do not grow as well as their heavier contemporaries and result in lower value carcasses. Expression of EGR-1 in umbilical cords of low birth weight pigs appears to reflect prenatal programming comparable to that identified in SGA babies

    Populist referendum : Was 'Brexit' an expression of nativist and anti-elitist sentiment?

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    Was the outcome of the United Kingdom’s ‘Brexit’ referendum to leave the European Union a visible and consequential manifestation of right-wing populism? After all, skepticism in the UK towards the EU predates the recent rise of European right wing populism. Original survey data show, however, that the interaction of nativist sentiment and anti-elitist attitudes, the cocktail of right-wing populism, led to widespread support for Brexit, even while controlling for other factors. Although hostility to immigrants was an important factor, nativists were particularly prone to vote ‘leave’; if they also did not trust political elites, a crucial element of populism. Further underscoring this explanation is the conditional effect of anti-elite sentiment. The relationship between anti-elite sentiment and support for leaving the EU only exists among those with high nativist sentiment; among those low in nativist sentiment, anti-elite feelings did not increase support for Brexit

    Occultation Light Curves of Io's Hot Spots in 2014

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    We present ground-based observations of Io during Spring 2014, contributing to decadal timelines of individual hot spots' volcanic activity
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