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Geologic and Hydrogeologic Framework of Regional Aquifers in the Twin Mountains, Paluxy, and Woodbine Formations Near the SSC Site, North-Central Texas
Water-utility districts and many municipalities in North-Central Texas
recently obtained as much as 100 percent of their water supply from deep
regional aquifers in Cretaceous formations. Use of groundwater from the
aquifers during the past century has resulted in water-level declines of as
much as 850 ft (259 m), especially in Dallas and Tarrant Counties. Future
water-level changes will depend on the amount of groundwater produced to
help meet growing water-supply needs for municipalities, industries, and
agriculture throughout North-Central Texas. It is probable that a significant
part of the increased water demand will be met by groundwater although at
less than historic rates.
The objective of this study was to develop a predictive tool for studying
the effect of future groundwater production from regional aquifers in North-Central
Texas. To do this, we reviewed the history of groundwater
development, hydrogeology of the regional aquifers, and constructed
numerical models of groundwater flow. A cross-sectional model of both
aquifers and confining layers was used to evaluate model boundary
conditions and the vertical hydrologic properties of the confining layers.
Results and insights from the cross-sectional model were used in a three-dimensional
simulation of groundwater flow in the deep aquifers. The layers
of the regional confining system were not explicitly included in the three-dimensional
model. Hydrogeologic properties were assigned on the basis of
aquifer test results and stratigraphic mapping of sandstone distribution in the
aquifer units.Bureau of Economic Geolog
Solar-Terrestrial Coupling Evidenced by Periodic Behavior in Geomagnetic Indexes and the Infrared Energy Budget of the Thermosphere
We examine time series of the daily global power (W) radiated by carbon dioxide (at 15 microns) and by nitric oxide (at 5.3 microns) from the Earth s thermosphere between 100 km and 200 km altitude. Also examined is a time series of the daily absorbed solar ultraviolet power in the same altitude region in the wavelength span 0 to 175 nm. The infrared data are derived from the SABER instrument and the solar data are derived from the SEE instrument, both on the NASA TIMED satellite. The time series cover nearly 5 years from 2002 through 2006. The infrared and solar time series exhibit a decrease in radiated and absorbed power consistent with the declining phase of the current 11-year solar cycle. The infrared time series also exhibits high frequency variations that are not evident in the solar power time series. Spectral analysis shows a statistically significant 9-day periodicity in the infrared data but not in the solar data. A very strong 9-day periodicity is also found to exist in the time series of daily A(sub p) and K(sub p) geomagnetic indexes. These 9-day periodicities are linked to the recurrence of coronal holes on the Sun. These results demonstrate a direct coupling between the upper atmosphere of the Sun and the infrared energy budget of the thermosphere
Real-time motion monitoring improves functional MRI data quality in infants
Imaging the infant brain with MRI has improved our understanding of early neurodevelopment. However, head motion during MRI acquisition is detrimental to both functional and structural MRI scan quality. Though infants are typically scanned while asleep, they commonly exhibit motion during scanning causing data loss. Our group has shown that providing MRI technicians with real-time motion estimates via Framewise Integrated Real-Time MRI Monitoring (FIRMM) software helps obtain high-quality, low motion fMRI data. By estimating head motion in real time and displaying motion metrics to the MR technician during an fMRI scan, FIRMM can improve scanning efficiency. Here, we compared average framewise displacement (FD), a proxy for head motion, and the amount of usable fMRI data (FD †0.2 mm) in infants scanned with (n = 407) and without FIRMM (n = 295). Using a mixed-effects model, we found that the addition of FIRMM to current state-of-the-art infant scanning protocols significantly increased the amount of usable fMRI data acquired per infant, demonstrating its value for research and clinical infant neuroimaging
The 4D SU(3) gauge theory with an imaginary theta term
We study the scaling behavior of the 4D SU(3) lattice gauge theory in the
presence of a theta term, by Monte Carlo simulations computing the topological
properties at imaginary theta. The numerical results provide a good evidence of
scaling in the continuum limit. The imaginary theta dependence of the
ground-state energy turns out to be well described by the first few terms of
related expansions around theta=0, providing accurate estimates of the first
few coefficients, up to O(theta^6).Comment: 12 page
Tau Neutrinos Favored over Sterile Neutrinos in Atmospheric Muon Neutrino Oscillations
The previously published atmospheric neutrino data did not distinguish
whether muon neutrinos were oscillating into tau neutrinos or sterile
neutrinos, as both hypotheses fit the data. Using data recorded in 1100
live-days of the Super-Kamiokande detector, we use three complementary data
samples to study the difference in zenith angle distribution due to neutral
currents and matter effects. We find no evidence favoring sterile neutrinos,
and reject the hypothesis at the 99% confidence level. On the other hand, we
find that oscillation between muon and tau neutrinos suffices to explain all
the results in hand.Comment: 9 pages with 2 figures, submitted to PR
Memorials to the victims of Nazism: the impact on tourists in Berlin
This qualitative study explores tourist responses to memorials to the victims of Nazism in Berlin and the impact they have on the tourist experience. The findings are located in the field of study known as dark tourism, of which visiting memorials is a part. The analysis shows that tourists increased their knowledge of the crimes committed by the Nazis, thus fulfilling the educational function of memorials. Tourists were also overwhelmed by their experience; they attested to feelings of sadness, shock, anger, despair and incomprehension. These feelings made it hard for them to resume the role of tourist after their exposure to a memorial. There was acknowledgement of the extent of commemoration practised in Germany
Constraints on Neutrino Oscillations Using 1258 Days of Super-Kamiokande Solar Neutrino Data
We report the result of a search for neutrino oscillations using precise
measurements of the recoil electron energy spectrum and zenith angle variations
of the solar neutrino flux from 1258 days of neutrino-electron scattering data
in Super-Kamiokande. The absence of significant zenith angle variation and
spectrum distortion places strong constraints on neutrino mixing and mass
difference in a flux-independent way. Using the Super-Kamiokande flux
measurement in addition, two allowed regions at large mixing are found.Comment: 6 pages, 4 figures, submitted to PR
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