578 research outputs found
Essays on incentives, economic conditions, and educational choices
In this dissertation, I offer two independent studies that each contribute to the literature on the college choices. The first paper examines the impact of Arizona’s merit based scholarship on college enrollment decisions. I find that both enrollment and tuition and fees increased at Arizona’s three large public institutions after the implementation of the AIMS scholarship. Enrollment effects are strongest among black and hispanic students. The second paper examines the impact of the recent 2009 housing crisis on college enrollment decisions. I find that large reductions in housing wealth lead to increases in public school enrollment and decreases in private school enrollment. Similarly, I find that increases in foreclosures in a metro area are associated with decreases in private school enrollment and increases in public school enrollment
Alien Registration- Upton, George V.,Jr. (Bangor, Penobscot County)
https://digitalmaine.com/alien_docs/10264/thumbnail.jp
Decomposing Crude Price Differentials: Domestic Shipping Constraints or the Crude Oil Export Ban?
Over the past five years the U.S. domestic crude benchmark, WTI, diverged considerably from its foreign counterpart, Brent. Some studies pointed to the crude oil export ban as the main culprit for this divergence, but pipeline capacity was also scarce during this time. To understand the drivers of domestic crude oil discounts, we decompose domestic price differentials for multiple crudes into the contributions of shipping and export constraints. We find that scarce pipeline capacity explains the majority of the deviation of mid-continent crude oil prices from their long-run relationship with Brent crude, while refining changes explain very little. This implies that the deleterious effects of the export ban may have been exaggerated
OPTIMAL IRRIGATION PIVOT LOCATION ON IRREGULARLY SHAPED FIELDS
Although annual rainfall in the Southeast is adequate, its distribution is a potential constraint to agricultural production. Farmers require production information concerning efficient use of irrigation technology adapted to regional growing conditions. Selection of optimal position, size, and number of pivots in center pivot irrigation systems poses special problems on small, irregularly shaped fields. In the southeastern United States, field size and shape are often varied and irregular. A mixed integer programming model was constructed to assist in irrigation investment decisions. The model is illustrated using irrigated peanut production in southeast Alabama. Results indicate the importance of economic engineering considerations.Farm Management,
Vol. 19, No. 4
Contents:
Bargaining Implications of the No Child Left Behind Act, by Michael A. Loizzi, Jr., Penny Upton and John L. Di John, Jr.
Recent Developments,
Further References, compiled by Margaret A. Chaplanhttps://scholarship.kentlaw.iit.edu/iperr/1072/thumbnail.jp
Vol. 19, No. 4
Contents:
Bargaining Implications of the No Child Left Behind Act, by Michael A. Loizzi, Jr., Penny Upton and John L. Di John, Jr.
Recent Developments,
Further References, compiled by Margaret A. Chaplanhttps://scholarship.kentlaw.iit.edu/iperr/1072/thumbnail.jp
Viral RNA at two stages of reovirus infection is required for the induction of necroptosis
Necroptosis, a regulated form of necrotic cell death, requires the activation of the RIP3 kinase. Here, we identify that infection of host cells with reovirus can result in necroptosis. We find that necroptosis requires sensing of the genomic RNA within incoming virus particles via cytoplasmic RNA sensors to produce type I interferon (IFN). While these events that occur prior to the de novo synthesis of viral RNA are required for the induction of necroptosis, they are not sufficient. The induction of necroptosis also requires late stages of reovirus infection. Specifically, efficient synthesis of double-stranded RNA (dsRNA) within infected cells is required for necroptosis. These data indicate that viral RNA interfaces with host components at two different stages of infection to induce necroptosis. This work provides new molecular details about events in the viral replication cycle that contribute to the induction of necroptosis following infection with an RNA virus. IMPORTANCE An appreciation of how cell death pathways are regulated following viral infection may reveal strategies to limit tissue destruction and prevent the onset of disease. Cell death following virus infection can occur by apoptosis or a regulated form of necrosis known as necroptosis. Apoptotic cells are typically disposed of without activating the immune system. In contrast, necroptotic cells alert the immune system, resulting in inflammation and tissue damage. While apoptosis following virus infection has been extensively investigated, how necroptosis is unleashed following virus infection is understood for only a small group of viruses. Here, using mammalian reovirus, we highlight the molecular mechanism by which infection with a dsRNA virus results in necroptosis
Three-dimensional Photoelastic Analysis of the Load Distribution in a Sucker-rod Joint
Mechanical Engineerin
Hard Superconductivity of a Soft Metal in the Quantum Regime
Superconductivity is inevitably suppressed in reduced dimensionality.
Questions of how thin superconducting wires or films can be before they lose
their superconducting properties have important technological ramifications and
go to the heart of understanding coherence and robustness of the
superconducting state in quantum-confined geometries. Here, we exploit quantum
confinement of itinerant electrons in a soft metal to stabilize superconductors
with lateral dimensions of the order of a few millimeters and vertical
dimensions of only a few atomic layers. These extremely thin superconductors
show no indication of defect- or fluctuation-driven suppression of
superconductivity and sustain supercurrents of up to 10% of the depairing
current density. The extreme hardness of the critical state is attributed to
quantum trapping of vortices. This study paints a conceptually appealing,
elegant picture of a model nanoscale superconductor with calculable critical
state properties. It indicates the intriguing possibility of exploiting robust
superconductivity at the nanoscale.Comment: 15 pages, 4 figures, submitted to Nature Physic
Conditions for Reionizing the Universe with A Low Galaxy Ionizing Photon Escape Fraction
We explore scenarios for reionizing the intergalactic medium with low galaxy
ionizing photon escape fractions. We combine simulation-based halo-mass
dependent escape fractions with an extrapolation of the observed galaxy
rest-ultraviolet luminosity functions to solve for the reionization history
from z=20 to z=4. We explore the posterior distributions for key unknown
quantities, including the limiting halo mass for star-formation, the ionizing
photon production efficiency, and a potential contribution from active galactic
nuclei (AGN). We marginalize over the allowable parameter space using a Markov
Chain Monte Carlo method, finding a solution which satisfies the most
model-independent constraints on reionization. Our fiducial model can match
observational constraints with an average escape fraction of <5% throughout the
bulk of the epoch of reionization if: i) galaxies form stars down to the atomic
cooling limit before reionization and a photosuppression mass of
log(M_h/Msol)~9 during/after reionization (-13<M_UV,lim<-11); ii) galaxies
become more efficient producers of ionizing photons at higher redshifts and
fainter magnitudes, and iii) there is a significant, but sub-dominant,
contribution by AGN at z -15)
dominate the ionizing emissivity, leading to an earlier start to reionization
and a smoother evolution of the ionized volume filling fraction than models
which assume a single escape fraction at all redshifts and luminosities. The
ionizing emissivity from this model is consistent with observations at z=4-5
(and below, when extrapolated), in contrast to some models which assume a
single escape fraction. Our predicted ionized volume filling fraction at z=7 of
Q_HII=78% (+\- 8%) is in ~1-2 sigma tension with observations of Lya emitters
at z~7 and the damping wing analyses of the two known z>7 quasars, which prefer
Q_HII,z=7~40-50%.Comment: 45 pages, 21 figures, accepted for publication in the Astrophysical
Journa
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