Non-equilibrium effects in steady relativistic e+e−γe^+e^-\gamma winds

We consider an ultra-relativistic wind consisting of electron-positron pairs and photons with the principal goal of finding the asymptotic Lorentz factor $\gamma_{\infty}$ for zero baryon number. The wind is assumed to originate at radius $r_i$ where it has a Lorentz factor $\gamma_i$ and a temperature $T_i$ sufficiently high to maintain pair equilibrium. As $r$ increases, $T$ decreases and becomes less than the temperature corresponding to the electron mass $m_e$, after which non-equilibrium effects become important. Further out in the flow the optical depth $\tau$ drops below one, but the pairs may still be accelerated by the photons until $\tau$ falls below $\sim 2\times10^{-5} \gamma_{i}^{3/4}$. Radiative transfer calculations show that only at this point do the radiation flux and pressure start to deviate significantly from their blackbody values. The acceleration of the pairs increases $\gamma$ by a factor $\sim 45$ as compared to its value at the photosphere; it is shown to approach \gamma_{\infty} \sim 1.4\times 10^3 (r_i/10^6\mbox{cm})^{1/4} \gamma_{i}^{3/4} T_i/m_e.Comment: 41 pages, 9 figures. Submitted to MNRA

How to allocate scarce health resources without discriminating against people with disabilities

One widely used method for allocating health care resources involves the use of cost-effectiveness analysis (CEA) to rank treatments in terms of quality-adjusted life-years (QALYs) gained. CEA has been criticized for discriminating against people with disabilities by valuing their lives less than those of non-disabled people. Avoiding discrimination seems to lead to the ’QALY trap’: we cannot value saving lives equally and still value raising quality of life. This paper reviews existing responses to the QALY trap and argues that all are problematic. Instead, we argue that adopting a moderate form of prioritarianism avoids the QALY trap and disability discrimination

Strong absorption and selective thermal emission from a mid-infrared metamaterial

We demonstrate thin-film metamaterials with resonances in the mid-infrared wavelength range. Our structures are numerically modeled and experimentally characterized by reflection and angularly-resolved thermal emission spectroscopy. We demonstrate strong and controllable absorption resonances across the mid-infrared wavelength range. In addition, the polarized thermal emission from these samples is shown to be highly selective and largely independent of emission angles from normal to 45 degrees. Experimental results are compared to numerical models with excellent agreement. Such structures hold promise for large-area, low-cost metamaterial coatings for control of gray- or black-body thermal signatures, as well as for possible mid-IR sensing applications.Comment: The following article has been submitted to Appl. Phys. Lett. After it is published, it will be found at http://apl.aip.org/. 14 pages including 4 figure page

Hohenberg-Kohn theorem for the lowest-energy resonance of unbound systems

We show that under well-defined conditions the Hohenberg-Kohn theorem (HKT) can be extended to the lowest-energy resonance of unbound systems. Using the Gel'fand Levitan theorem, the extended version of the HKT can also be applied to systems that support a finite number of bound states. The extended version of the HKT provides an adequate framework to carry out DFT calculations of negative electron affinities.Comment: 4 pages, 3 figure

Merits Stripping

As the debate rages about the power and wisdom of Congress to “strip” federal courts of jurisdiction to adjudicate particular controversial federal issues, the discussion either ignores another means of constricting the power and influence of the courts. That is the distinct act of “merits stripping.” Merits stripping eliminates, limits, or diminishes enforceable substantive rights and the merits of claims brought to enforce those rights. Merits strips diminish the amount of real-world actors and conduct subject to legal duties and protected by legal rights. Merits striping limits who can sue whom over what conduct. Merits strips can target statutory or constitutional rights and can be affected by the legislative, executive, or judicial departments, acting individually or in concert. A “strip” occurs whenever the scope of legal rights (and the legal duties those rights impose on others) falls below some baseline of preexisting law or normative preference. Unfortunately, courts and commentators often conflate merits stripping with true jurisdiction stripping. But they are necessarily distinct concepts and such conflation confounds our ability to understand both. Three differences loom. First, while jurisdiction strips shift litigation out of federal court and into another forum (presumably state courts), merits strips eliminate enforceable rights altogether, in any forum. Second, the manner of litigating and resolving legal and factual issues will be different, depending on whether the “stripping enactment” being applied in court targets merits or jurisdiction; this distinction between merits stripping and jurisdiction stripping is a sub-category of the broader differences between judicial jurisdiction and substantive merits. Third, and most importantly, the structural and constitutional controversy surrounding the power to jurisdiction strip does not apply to merits stripping. Congress clearly has the power to redefine statutory rights, including narrowing those rights; courts clearly have the power to define constitutional rights, including narrowing those rights. One might disagree with the resulting scope of federal rights. But one cannot question the basic power to define those rights. This article defines and examines multiple examples of merits stripping of federal statutory and constitutional rights. It then considers the differences between merits stripping and jurisdiction stripping and how those differences play out in court. Ultimately, distinguishing these concepts is essential to understanding the operation of federal law in the federal courts

After-School Programs and Academic Impact: A Study of Chicago's After School Matters

What impact can after-school programs have on the educational achievement of high school students? A new study of Chicago's After School Matters (ASM) program -- which offers paid internships in the arts, technology, sports, and communications to teenagers in some of the city's most underserved schools -- finds a relationship between participating in after-school activities and higher class attendance, lower course failures and higher graduation rates.Even after taking into account student demographic characteristics and prior attendance records, students who participate in ASM miss fewer days of school than their classmates. Similarly, students who participated at the highest levels in the after-school program tended to fail fewer core academic courses (English, Math, Science, and Social Studies). Furthermore, over the course of their time in high school, students who were enrolled in ASM for three or more semesters and those who participated at the highest levels had higher rates of graduation and lower dropout rates than similar students who did not participate in the program.The findings in this report highlight the importance of further research into what leads students to participate in after-school programs and the factors that lead to higher engagement and retention once they are enrolled. A better understanding is crucial for improving enrollment in after-school programs such as ASM. Moreover, accounting for student factors that lead to a greater engagement in the program will lead to a clearer understanding of ASM's contribution to the positive outcomes -- independent of hard-to-observe student characteristics such as enthusiasm or dedication