114 research outputs found
White House/OSTP perspective
Two aspects of the Office of Science and Technology Policy (OSTP) are discussed: (1) efforts to state the overarching technology policy in which technology transfer plays an important part; and (2) efforts to coordinate federal R&D contracts programs in several technology areas through the Federal Coordinating Council for Science, Engineering, and Technology (FCCSET) process
Modeled nitrogen loading to Narragansett Bay: 1850 to 2015
Nutrient loading to estuaries with heavily populated watersheds can have profound ecological consequences. In evaluating policy options for managing nitrogen (N), it is helpful to understand current and historic spatial loading patterns to the system. We modeled N inputs to Narragansett Bay from 1850 to 2000, using data on population, human waste disposal, livestock, fertilizer, and atmospheric deposition. We found that total N loading to the bay increased 250% from 1850 to 2000, and 80% from 1900 to 2000. Loading to the upper bay increased far more than that to the lower bay, and the most important source shifted from non-point animal waste to human waste concentrated at sewage treatment facilities. We also modeled future N loads in 2015 under four management scenarios. Planned improvements in sewage treatment would reduce N loads 9% below business-as-usual, to the 1990 loading rate. Greater reductions, to circa 1900 rates of loading, may be possible
The Influence of Clay Flocculation and Dispersion on the Covering Power of Clay Coating Colors
Historical Survey
Introduction
A survey of the literature showed that considerable information has been published on the effects of dispersing agents on the viscosity of coating colors and clay slurries. There seemed to be little work done on the effect of the dispersing agent on any other of the properties of the coating
Nitrogen Loading From Wastewater Treatment Plants To Upper Narragansett Bay
Increasing awareness of low-oxygen conditions in Narragansett Bay, as well as other
symptoms of eutrophication such as macroalgae accumulation, eelgrass failure, and fish
kills, has led to management actions to reduce nitrogen loads to the upper Ba
920-52 Are Provider Profiles Affected by Risk-adjustment Methodology? Results from the Cooperative Cardiovascular Project
Health care payors and consumers have a growing interest in risk-adjusted provider profiles. Using chart-abstracted clinical data from the Cooperative Cardiovascular Project, we ranked 28 hospitals performing bypass surgery in Alabama and Iowa by their risk-adjusted surgical mortality rates using three published risk-adjustment methodologies: Parsonnet (PI, O’Connor (a) and Hannan (H). In total. 3653 bypass surgery cases performed from 6/92 to 3/93 were reviewed (mean 130 cases/hospital). The discriminatory abilities of each method for predicting surgical mortality were quite similar (area under ROC curves 0.72–0.75). Below, we display the risk-adjusted hospital rankings (comparing observed with expected mortality) by these three riskadjustment techniques:In terms of hospital rankings, there was generally close correlation between any two of the methods (Spearman's R=0.87,0.88, and 0.93, comparing P-O, P-H, and H-O). Rankings for an individual hospital varied, however, an average of ±3.3 ranks (range 0–12 ranks) depending on which riskadjustment methodology was used.ConclusionIn general. published methods of risk-adjustment for bypass surgery accurately identify institutions with low, moderate and high adjusted mortality outcomes. The precise ranking of an individual hospital. however, may vary depending on the risk adjustment method applied
Chiral Gauge Theories and Fermion-Higgs Systems
Summary talk presented at the Conference on Lattice Field Theory, Amsterdam,
September, 1992. Abstract: The status of several proposals for defining a
theory of chiral fermions on the lattice is reviewed and some new estimates for
the upper bound on the Higgs mass are presented.Comment: 16 pages, LaTeX, Wash.U.HEP-92-8
Interspecific Communicative and Coordinated Hunting between Groupers and Giant Moray Eels in the Red Sea
Intraspecific group hunting has received considerable attention because of the close links between cooperative behaviour and its cognitive demands. Accordingly, comparisons between species have focused on behaviours that can potentially distinguish between the different levels of cognitive complexity involved, such as “intentional” communication between partners in order to initiate a joint hunt, the adoption of different roles during a joint hunt (whether consistently or alternately), and the level of food sharing following a successful hunt. Here we report field observations from the Red Sea on the highly coordinated and communicative interspecific hunting between the grouper, Plectropomus pessuliferus, and the giant moray eel, Gymnothorax javanicus. We provide evidence of the following: (1) associations are nonrandom, (2) groupers signal to moray eels in order to initiate joint searching and recruit moray eels to prey hiding places, (3) signalling is dependent on grouper hunger level, and (4) both partners benefit from the association. The benefits of joint hunting appear to be due to complementary hunting skills, reflecting the evolved strategies of each species, rather than individual role specialisation during joint hunts. In addition, the partner species that catches a prey item swallows it whole immediately, making aggressive monopolisation of a carcass impossible. We propose that the potential for monopolisation of carcasses by one partner species represents the main constraint on the evolution of interspecific cooperative hunting for most potentially suitable predator combinations
Investigation of the Domain Wall Fermion Approach to Chiral Gauge Theories on the Lattice
We investigate a recent proposal to construct chiral gauge theories on the
lattice using domain wall fermions. We restrict ourselves to the finite volume
case, in which two domain walls are present, with modes of opposite chirality
on each of them. We couple the chiral fermions on only one of the domain walls
to a gauge field. In order to preserve gauge invariance, we have to add a
scalar field, which gives rise to additional light mirror fermion and scalar
modes. We argue that in an anomaly free model these extra modes would decouple
if our model possesses a so-called strong coupling symmetric phase. However,
our numerical results indicate that such a phase most probably does not exist.
---- Note: 9 Postscript figures are appended as uuencoded compressed tar file.Comment: 27p. Latex; UCSD/PTH 93-28, Wash. U. HEP/93-6
Auroral beads at Saturn and the driving mechanism:Cassini proximal orbits
During the Grand Finale Phase of Cassini, the Ultraviolet Imaging Spectrograph on board the spacecraft detected repeated detached small-scale auroral structures. We describe these structures as auroral beads, a term introduced in the terrestrial aurora. Those on DOY 232 2017 are observed to extend over a large range of local times, i.e., from 20 LT to 11 LT through midnight. We suggest that the auroral beads are related to plasma instabilities in the magnetosphere, which are often known to generate wavy auroral precipitations. Energetic neutral atom enhancements are observed simultaneously with auroral observations, which are indicative of a heated high pressure plasma region. During the same interval we observe conjugate periodic enhancements of energetic electrons, which are consistent with the hypothesis that a drifting interchange structure passed the spacecraft. Our study indicates that auroral bead structures are common phenomena at Earth and giant planets, which probably demonstrates the existence of similar fundamental magnetospheric processes at these planets
Energetic particle signatures above Saturn’s aurorae
Near the end of its mission, NASA's Cassini spacecraft performed several low‐altitude passes across Saturn's auroral region. We present auroral imagery and various coincident particle and field measurements of two such passes, providing important information about the structure and dynamics of Saturn's auroral acceleration region. In upward field‐aligned current regions, upward proton beams are observed to reach energies of several tens of keV; the associated precipitating electron populations are found to have mean energies of about 10 keV. With no significant wave activity being apparent, these findings indicate strong parallel potentials responsible for auroral acceleration; about 100 times stronger than at Earth. This is further supported by observations of proton conics in downward field‐aligned current regions above the acceleration region, which feature a lower energy cutoff above ~50 keV ‐ indicating energetic proton populations trapped by strong parallel potentials while being transversely energized until they can overcome the trapping potential, likely through wave‐particle interactions. A spacecraft pass through a downward current region at an altitude near the acceleration region reveals plasma wave features which may be driving the transverse proton acceleration generating the conics. Overall, the signatures observed resemble those related to the terrestrial and Jovian aurorae, the particle energies and potentials at Saturn appearing to be significantly higher than at Earth and comparable to those at Jupiter
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