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Features And Flaws Of A Fair Hospital Policy For Allocating Expensive Charity Care To Noncitizen Patients

Commentators have asserted that the existence of a genuine medical need constitutes a moral claim on those equipped to help. However, this professional duty is sharply limited by the fact that resources are not available to help all the world\u27s patients with each of their problems. At some point, boundaries are drawn implicitly and by force; these boundaries can exacerbate inequalities and injustices, or they can contribute to making the medical system more fair for everyone it serves. To achieve a more just result, distributive justice must be employed, but any systematic way of allocating resources depends on being able to define who belongs to a public and thus deserves treatment, as well as what any minimum basic right to treatment should entail. By examining closely a case of an adolescent undocumented immigrant who traveled from her home country explicitly for treatment of a fast-growing tumor, we will explore a variety of ethical concerns related to this dilemma in its historical and political context. Finally, a pragmatic hospital-based policy to guide microallocation of expensive charity care will be proposed in hopes of seeking a reasonably fair process to adjudicate this increasingly common dilemma of politics, economics, and professional ethics

Tunable Semiconductors: Control over Carrier States and Excitations in Layered Hybrid Organic-Inorganic Perovskites

For a class of 2D hybrid organic-inorganic perovskite semiconductors based on $\pi$-conjugated organic cations, we predict quantitatively how varying the organic and inorganic component allows control over the nature, energy and localization of carrier states in a quantum-well-like fashion. Our first-principles predictions, based on large-scale hybrid density-functional theory with spin-orbit coupling, show that the interface between the organic and inorganic parts within a single hybrid can be modulated systematically, enabling us to select between different type-I and type-II energy level alignments. Energy levels, recombination properties and transport behavior of electrons and holes thus become tunable by choosing specific organic functionalizations and juxtaposing them with suitable inorganic components

Application of fluvial scaling relationships to reconstruct drainage-basin evolution and sediment routing for the Cretaceous and Paleocene of the Gulf of Mexico

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.Fluvial systems represent a key component in source-to-sink analysis of ancient sediment-dispersal systems. Modern river channels and channel-related deposits possess a range of scaling relationships that reflect drainage-basin controls on water and sediment flux. For example, channel-belt sand-body thicknesses scale to bankfull discharge, and represent a reliable first-order proxy for contributing drainage-basin area, a proxy that is more robust if climatic regimes can be independently constrained. A database of morphometrics from Quaternary channel belts provides key modern fluvial system scaling relationships, which are applied to Cretaceous- to Paleocene-age fluvial deposits. This study documents the scales of channel-belt sand bodies within fluvial successions from the northern Gulf of Mexico passive-margin basin fill from well logs, and uses scaling relationships developed from modern systems to reconstruct the scale of associated sediment-routing systems and changes in scale through time. We measured thicknesses of 986 channel-belt sand bodies from 248 well logs so as to estimate the scales of the Cretaceous (Cenomanian) Tuscaloosa-Woodbine, Paleocene–early Eocene Wilcox, and Oligocene Vicksburg-Frio fluvial systems. These data indicate that Cenozoic fluvial systems were significantly larger than their Cenomanian counterparts, which is consistent with Cretaceous to Paleocene continental-scale drainage reorganization that routed water discharge and sediment from much of the continental United States to the Gulf of Mexico. At a more detailed level, Paleocene–early Eocene Wilcox fluvial systems were larger than their Oligocene counterparts, which could reflect decreases in drainage-basin size and/or climatic change within the continental interior toward drier climates with less runoff. Additionally, these data suggest that the paleo–Tennessee River, which now joins the Ohio River in the northernmost Mississippi embayment of the central United States, was an independent fluvial system, flowing southwest to the southern Mississippi embayment, or directly to the Gulf of Mexico, through the early Eocene. Changes in scaling relationships through time, and interpreted changes in the scales of contributing drainage basins, are generally consistent with previously published regional paleogeographic maps, as well as with newly published maps of paleodrainage from detrital-zircon provenance and geochronological studies. As part of a suite of metrics derived from modern systems, scaling relationships make it possible to more fully understand and constrain the scale of ancient source-to-sink systems and their changes through time, or cross-check interpretations made by other means