4,108 research outputs found
Copper emissions from a high volume air sampler
High volume air samplers (hi vols) are described which utilize a brush-type electric motor to power the fans used for pulling air through the filter. Anomalously high copper values were attributed to removal of copper from the commutator into the air stream due to arcing of the brushes and recirculation through the filter. Duplicate hi vols were set up under three operating conditions: (1) unmodified; (2) gasketed to prevent internal recirculation; and (3) gasketed and provided with a pipe to transport the motor exhaust some 20 feet away. The results of 5 days' operation demonstrate that hi vols can suddenly start emitting increased amounts of copper with no discernible operational indication, and that recirculation and capture on the filter can take place. Copper levels found with hi vols whose exhaust was discharged at a distance downwind were among the lowest found, and apparently provides a satisfactory solution to copper contamination
Characterization and analysis of azimuthally sensitive correlations
A unified framework for describing the azimuthal dependence of two-particle
correlations in heavy-ion collisions is introduced, together with the methods
for measuring the corresponding observables. The generalization to azimuthal
correlations between more than two particles is presented.Comment: 7 pages; talk given at Hot Quarks 2004, Taos (NM), July 18-24,200
Intercollegiate Athletics, Institutional Aspirations, and Why Legitimacy Is More Compelling than Sustainability
A PARTIAL EQUILIBRIUM MODEL OF THE LINKAGES BETWEEN ANIMAL WELFARE, TRADE AND THE ENVIRONMENT IN SCOTLAND
This research analyses the impacts of a scientific advance that improves animal welfare, upon the environment and trade in Scotland using partial equilibrium (PE) modelling. The science improves pig neonatal survival through improved (high fibre) sow diets used before mating. Our model simulates the effects of animal welfare changes on the pig production systems (pig meat) and further on trade flows (trade in pig meat) and environment (water and air pollution). We consider two animal welfare simulation scenarios, namely the status quo â no animal welfare change as regards pig neonatal mortality (baseline scenario) and the case of improving pig neonatal survival (alternative scenario) and compare the impacts on trade and environment between the two scenarios during the simulation horizon 2008-2015. The results show that the increase in animal welfare has a lower impact on the environment in the alternative scenario compared to the baseline scenario (by about 6% at the end of the simulation horizon) and a positive impact on net trade in the alternative scenario compared to the baseline scenario (by about 13% at the end of the simulation horizon).Pig Welfare, Trade, Environment, Scotland, Partial Equilibrium Model., Agricultural and Food Policy, Environmental Economics and Policy, Research Methods/ Statistical Methods, Q18, Q50,
Short-duration gamma-ray bursts from off-axis collapsars
We present 2D high-resolution hydrodynamic simulations of the relativistic
outflows of long-duration gamma-ray burst progenitors. We analyze the
properties of the outflows at wide off-axis angles, produced by the expansion
of the hot cocoon that surrounds the jet inside the progenitor star. We find
that the cocoon emission at wide angles may have properties similar to those of
the subclass of short-duration gamma-ray bursts with persistent X-ray emission.
We compute the predicted duration distribution, redshift distribution, and
afterglow brightness and we find that they are all in agreement with the
observed properties of short GRBs with persistent emission. We suggest that a
SN component, the properties of the host galaxies, and late afterglow
observations can be used as a crucial test to verify this model.Comment: 5 pages, 6 color figures, accepted for publication in ApJ, main
journa
Filter cassette for high volume air sampler
Filter cassette eliminates or substantially reduces contamination of filter media by extraneous material and facilitates handling
When "It" becomes "Mine": attentional biases triggered by object ownership.
Abstract
Previous research has demonstrated that higher-order cognitive processes associated with the allocation of selective attention are engaged when highly familiar self-relevant items are encountered, such as one's name, face, personal possessions and the like. The goal of our study was to determine whether these effects on attentional processing are triggered on-line at the moment self-relevance is established. In a pair of experiments, we recorded ERPs as participants viewed common objects (e.g., apple, socks, and ketchup) in the context of an âownershipâ paradigm, where the presentation of each object was followed by a cue indicating whether the object nominally belonged either to the participant (a âselfâ cue) or the experimenter (an âotherâ cue). In Experiment 1, we found that âselfâ ownership cues were associated with increased attentional processing, as measured via the P300 component. In Experiment 2, we replicated this effect while demonstrating that at a visualâperceptual level, spatial attention became more narrowly focused on objects owned by self, as measured via the lateral occipital P1 ERP component. Taken together, our findings indicate that self-relevant attention effects are triggered by the act of taking ownership of objects associated with both perceptual and postperceptual processing in cortex.</jats:p
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