10,785 research outputs found
The origin and evolution of terrestrial and Martian rock labyrinths
The morphological characteristics and evolutionary development of rock labyrinths on Earth (in sandstone, volcanics, and carbonates) are compared with those on Mars. On Earth rock labyrinths originate as parallel, an echelon, or intersecting narrow grabens, or develop where fault and joint networks are selectively eroded. Labyrinths frequently contain both downfaulted and erosional elements. Closed labyrinths contain depressions; open labyrinths do not, they are simple part of a fluvial network generally of low order. As closed labyrinths made up of intersecting grabens or made up of connected erosional depressions are extremely common on Mars, the research focussed on an understanding of these labyrinth types. Field investigations were carried out in Canyonlands National Park, Utah, and in the Chirachahua Mountains of Arizona. Martian labyrinths were investigated using Viking orbiter images. In addition, research was undertaken on apparent thermokarst features in Lunae Planum and Chryse Planitia where closed depressions are numerous and resemble atlas topography
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Technological needs of advanced Earth-observation spacecraft
An outline of the type of Earth observations needed is presented. The characteristics of a 120 meter by 60 meter microwave radiometer are discussed along with those of supplementary instruments
Federalism and Foreign Affairs: How to Remedy Violations of the Vienna Convention and Obey the U.S. Constitution, Too
This Note discusses various ways to bring the United States into better compliance with the 1963 Vienna Convention on Consular Relations The introduction to this Note discusses how violations of the Vienna Convention are currently treated in the United States. In particular, the introduction discusses the unsuccessful attempts to prevent the execution of Karl and Walter LaGrand, two German nationals sentenced to death in Arizona. The LaGrands were convicted after a violation of their rights under the Vienna Convention because they were not informed without delay of their right to consular notification and assistance. In later appeals, United States courts refused to review or reconsider the sentence on the basis of the Vienna Convention violation, because the LaGrands had procedurally defaulted the claim. The introduction notes that after the death of Karl and Walter LaGrand, the World Court declared the United States had violated the Vienna Convention, and that it must allow reconsideration and review of death sentences in future cases where consular rights have not been given.
Section one of this Note argues that the federal government has the power to force the States into compliance with the Vienna convention. Subsequent sections of the Note discuss how various branches of the federal government might attempt to force the States to comply.
Section two discusses how the judicial branch might seek to enforce the Vienna Convention upon the states. Section two argues that the United States Courts can and should employ the World Court\u27s view of the scope of consular rights contained within the Vienna Convention. This section also addresses the thornier problem of sovereign immunity and argues that the Eleventh Amendment should not prevent the federal government from enforcing the Vienna Convention, because the States may not raise the Eleventh Amendment to avoid the effects of a international treaty. Section two argues that even if the Eleventh Amendment does apply to binding international treaties, it does not apply to cases like LaGrand, because these cases clearly fall into the exception to the Eleventh Amendment established by Ex Parte Young.
Section three discusses whether the executive branch could stay or commute a State death sentence for a foreign national, on the ground that the sentence was rendered in violation of the Vienna Convention. This section concludes that an attempt by the executive to delay an execution on these grounds would probably fail because it would fall outside of the President\u27s authority to see the laws are faithfully executed.
Section four of this Note discusses the power of Congress to enforce the Vienna convention against the States. The primary obstacle to such an attempt would be the anti-commandeering doctrine of Printz v. United States. This section argues that the anti-commandeering doctrine does not extend to the treaty power. It goes on to propose several routes congress could use to ensure compliance with the Vienna Convention. Congress could enforce the Vienna convention by: using the conditional spending power; expanding federal habeas corpus jurisdiction; creating an independent federal cause of action for violations of the Vienna convention; expressly granting the President limited clemency power; or directly pre-empting State death penalty law with a federal law tracking the Vienna Convention
Identifying Gait Abnormalities in Patients with Femoroacetabular Impingement Syndrome
OBJECTIVE: To determine the biomechanical gait characteristics and quality of life of adults with femoroacetabular impingement (FAI) and how their gait compares to the gait of healthy controls. METHODS: Gait analyses were performed on 18 participants (9 FAI, 9 control) while walking barefoot in the Wolf Orthopeadic Biomechanics Lab. In addition, FAI participants completed general and region specific quality of life questionnaires. RESULTS: Hip moment (5.2%BW*ht vs. 4.96%BW*ht), toe out angle (12.36 ° vs. 8.15°), and lateral (3.55° vs. 2.18°) and forward (4.34° vs. 3.93°) pelvic tilt were not statistically different between groups. Trunk lean (1.33° vs. 0.36°), hip flexion angle (25.74° vs. 24.23°), & hip power (1.22W vs. 0.61W; p-value=0.32) were greater in the control group.CONCLUSION: The small sample size of this study does not allow the authors to make conclusions on the abnormalities in gait biomechanics in FAI patients. Further research with larger sample sizes is warranted
The Role of Cold Flows in the Assembly of Galaxy Disks
We use high resolution cosmological hydrodynamical simulations to demonstrate
that cold flow gas accretion, particularly along filaments, modifies the
standard picture of gas accretion and cooling onto galaxy disks. In the
standard picture, all gas is initially heated to the virial temperature of the
galaxy as it enters the virial radius. Low mass galaxies are instead dominated
by accretion of gas that stays well below the virial temperature, and even when
a hot halo is able to develop in more massive galaxies there exist dense
filaments that penetrate inside of the virial radius and deliver cold gas to
the central galaxy. For galaxies up to ~L*, this cold accretion gas is
responsible for the star formation in the disk at all times to the present.
Even for galaxies at higher masses, cold flows dominate the growth of the disk
at early times. Within this modified picture, galaxies are able to accrete a
large mass of cold gas, with lower initial gas temperatures leading to shorter
cooling times to reach the disk. Although star formation in the disk is
mitigated by supernovae feedback, the short cooling times allow for the growth
of stellar disks at higher redshifts than predicted by the standard model.Comment: accepted to Ap
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