Laplacian-level density functionals for the kinetic energy density and exchange-correlation energy

We construct a Laplacian-level meta-generalized gradient approximation (meta-GGA) for the non-interacting (Kohn-Sham orbital) positive kinetic energy density $\tau$ of an electronic ground state of density $n$. This meta-GGA is designed to recover the fourth-order gradient expansion $\tau^{GE4}$ in the appropiate slowly-varying limit and the von Weizs\"{a}cker expression $\tau^{W}=|\nabla n|^2/(8n)$ in the rapidly-varying limit. It is constrained to satisfy the rigorous lower bound $\tau^{W}(\mathbf{r})\leq\tau(\mathbf{r})$. Our meta-GGA is typically a strong improvement over the gradient expansion of $\tau$ for atoms, spherical jellium clusters, jellium surfaces, the Airy gas, Hooke's atom, one-electron Gaussian density, quasi-two dimensional electron gas, and nonuniformly-scaled hydrogen atom. We also construct a Laplacian-level meta-GGA for exchange and correlation by employing our approximate $\tau$ in the Tao, Perdew, Staroverov and Scuseria (TPSS) meta-GGA density functional. The Laplacian-level TPSS gives almost the same exchange-correlation enhancement factors and energies as the full TPSS, suggesting that $\tau$ and $\nabla^2 n$ carry about the same information beyond that carried by $n$ and $\nabla n$. Our kinetic energy density integrates to an orbital-free kinetic energy functional that is about as accurate as the fourth-order gradient expansion for many real densities (with noticeable improvement in molecular atomization energies), but considerably more accurate for rapidly-varying ones.Comment: 9 pages, 16 figure

Coded Aperture and Compton Imaging for the Development of 225^{225}Ac-based Radiopharmaceuticals

Targeted alpha-particle therapy (TAT) has great promise as a cancer treatment. Arguably the most promising TAT radionuclide that has been proposed is $^{225}$Ac. The development of $^{225}$Ac-based radiopharmaceuticals has been hampered due to the lack of effective means to study the daughter redistribution of these agents in small animals at the preclinical stage. The ability to directly image the daughters, namely $^{221}$Fr and $^{213}$Bi, via their gamma-ray emissions would be a boon for preclinical studies. That said, conventional medical imaging modalities, including single photon emission computed tomography (SPECT) based on pinhole collimation, cannot be employed due to sensitivity limitations. As an alternative, we propose the use of both coded aperture and Compton imaging with the former modality suited to the 218-keV gamma-ray emission of $^{221}$Fr and the latter suited to the 440-keV gamma-ray emission of $^{213}$Bi. This work includes coded aperture images of $^{221}$Fr and Compton images of $^{213}$Bi in tumor-bearing mice injected with $^{225}$Ac-based radiopharmaceuticals. These results are the first demonstration of visualizing and quantifying the $^{225}$Ac daughters in small animals via coded aperture and Compton imaging and serve as a stepping stone for future radiopharmaceutical studies

Brief of Corporate Law Professors as Amici Curie in Support of Respondents

The Supreme Court has looked to the rights of corporate shareholders in determining the rights of union members and non-members to control political spending, and vice versa. The Court sometimes assumes that if shareholders disapprove of corporate political expression, they can easily sell their shares or exercise control over corporate spending. This assumption is mistaken. Because of how capital is saved and invested, most individual shareholders cannot obtain full information about corporate political activities, even after the fact, nor can they prevent their savings from being used to speak in ways with which they disagree. Individual shareholders have no “opt out” rights or practical ability to avoid subsidizing corporate political expression with which they disagree. Nor do individuals have the practical option to refrain from putting their savings into equity investments, as doing so would impose damaging economic penalties and ignore conventional financial guidance for individual investors

Religions and Social Progress:Critical Assessments and Creative Partnerships

This chapter engages with three important themes of the larger report: the meaning of progress, its uneven nature, and obstacles to future progress. It also considers a number of political and economic alternatives aimed to overcome these obstacles, emphasizing the need for diverse strategies, open-minded experimentation, and scientific assessment. While it may be impossible to ever reach agreement, the effort to calibrate different interpretations of progress remains an important exercise for political deliberation about how to make the world a better place. The very hope of moving forward implies some agreement on a destination. All of us must take responsibility for the future. Our discussion emphasizes the complexity and multidimensionality of the interpretive debate, but also calls attention to its ideological character. Social actors-individuals, groups, and even academic disciplines-tend to define progress in ways that serve their own interests. In a way, distributional conflict undermines our very efforts to better understand and mediate such conflict. The uneven character of progress is manifest in many different domains. Increases in the global reach of formally democratic institutions have been accompanied by growing concerns about their stability, efficacy, and consistency with democratic ideals

A Closer Look at Self-Esteem, Perceived Social Support, and Coping Strategy: A Prospective Study of Depressive Symptomatology Across the Transition to College

The first year of college is a significant life transition, which is often characterized by stress and may contribute to the development or exacerbation of depressive symptoms. Due to the considerable negative outcomes that are associated with depressive symptoms across the lifespan, it is important to understand the mechanisms and pathways through which depressive symptoms arise. This prospective study examines the mediating and moderating roles of perceived social support and disengagement coping on the association between self-esteem and depressive symptomatology in a sample of 1,118 first-year college students. Results of longitudinal cross-lagged path analyses indicate that self-esteem predicts depressive symptomatology via perceived social support and disengagement coping. The association between self-esteem and perceived social support appear to be bidirectional, in that level of self-esteem predicts perceived social support, and vice versa. Furthermore, disengagement coping was found to moderate the effect of self-esteem on depressive symptomatology, in that increased levels of disengagement coping led to greater depressive symptoms within the context of both high and low self-esteem. However, this pattern was not observed at lower levels of disengagement coping, which indicates high levels of disengagement coping as a particular risk factor for depressive symptomatology, diminishing the advantage of high self-esteem

A hazard analysis method for systematic identification of safety requirements for user interface software in medical devices

© Springer International Publishing AG (outside the US) 2017. Formal methods technologies have the potential to verify the usability and safety of user interface (UI) software design in medical devices, enabling significant reductions in use errors and consequential safety incidents with such devices. This however depends on comprehensive and verifiable safety requirements to leverage these techniques for detecting and preventing flaws in UI software that can induce use errors. This paper presents a hazard analysis method that extends Leveson’s System Theoretic Process Analysis (STPA) with a comprehensive set of causal factor categories, so as to provide developers with clear guidelines for systematic identification of use-related hazards associated with medical devices, their causes embedded in UI software design, and safety requirements for mitigating such hazards. The method is evaluated with a case study on the Gantry-2 radiation therapy system, which demonstrates that (1) as compared to standard STPA, our method allowed us to identify more UI software design issues likely to cause use-related hazards; and (2) the identified UI software design issues facilitated the definition of precise, verifiable safety requirements for UI software, which could be readily formalized in verification tools such as Prototype Verification System (PVS).- U.S. Food and Drug Administration(NORTE-01-0145-FEDER-000016)Sandy Weininger (FDA), Scott Thiel (Navigant Consulting, Inc.), Michelle Jump (Stryker), Stefania Gnesi (ISTI/CNR) and the CHI+MED team (www.chi-med.ac.uk) provided useful feedback and inputs. Paolo Masci’s work is supported by the North Portugal Regional Operational Programme (NORTE 2020) under the PORTUGAL 2020 Partnership Agreement, and by the European Regional Development Fund (ERDF) within Project “NORTE-01-0145-FEDER-000016”.info:eu-repo/semantics/publishedVersio

The prognostic value of p53 mutation in pediatric marrow hypoplasia

<p>Abstract</p> <p>Background</p> <p>The tumor suppressor gene p53 is involved in the control of cell proliferation, particularly in stressed cells. p 53 gene mutations are the most frequent genetic event found in human cancers. Fanconi Anemia (FA) is the most common representative of inherited bone marrow failure syndromes (IBMFS) with a leukemic propensity. P 53 DNA alteration has not been studied before in Egyptian children with FA.</p> <p>Patients and methods</p> <p>we investigated p53 mutation in the bone marrow and peripheral blood of forty children, FA (n = 10), acquired aplastic anemia (AAA) (n = 10), and immune thrombocytopenia (ITP) as a control (n = 20), using real-time PCR by TaqMan probe assay</p> <p>Results</p> <p>Mutation of p53 gene was demonstrated in the BM of 90% (9/10) of children with FA, compared to 10% (1/10) in AAA (p < 0.001), while, no p53 DNA mutation was seen in the control group. A positive correlation between DNA breakage and presence of p53 mutation was seen in FA (p < 0.02, r0.81).</p> <p>Conclusion</p> <p>mutation of p53 gene in hypoplastic marrow especially FA may represent an early indicator of significant DNA genetic alteration with cancer propensity.</p

Supreme Court Amicus Brief of 19 Corporate Law Professors, Friedrichs v. California Teachers Association, No. 14-915

The Supreme Court has looked to the rights of corporate shareholders in determining the rights of union members and non-members to control political spending, and vice versa. The Court sometimes assumes that if shareholders disapprove of corporate political expression, they can easily sell their shares or exercise control over corporate spending. This assumption is mistaken. Because of how capital is saved and invested, most individual shareholders cannot obtain full information about corporate political activities, even after the fact, nor can they prevent their savings from being used to speak in ways with which they disagree. Individual shareholders have no “opt out” rights or practical ability to avoid subsidizing corporate political expression with which they disagree. Nor do individuals have the practical option to refrain from putting their savings into equity investments, as doing so would impose damaging economic penalties and ignore conventional financial guidance for individual investors

Not So Lucky Any More: CEO Compensation in Financially Distressed Firms

There is a debate on whether executive pay reflects rent extraction due to managerial power or is the result of arms-length bargaining in a principal-agent framework. In this paper we offer a test of the managerial power hypothesis by empirically examining the CEO compensation of U.S. public companies that were ever in financial distress between 1992 and 2005. Using a bias-corrected matching estimator that estimates the causal effects of financial distress, we find that, for the distressed firms, CEO turnover rates increase markedly and their CEOs, both incumbents and successors, experience significant reductions in total compensation. The bulk of the reduction in total compensation derives from the decline in value of stock option grants, which we argue is due to a change in the opportunistic timing of option grants. We define lucky grants as those with grant prices below or at the lowest stock price of the grant month, and we find that the proportion of lucky grants for financially distressed firms is higher before insolvency and lower upon and after insolvency, while the proportion for similar but solvent firms remains stable throughout the period. We interpret this evidence as consistent with a decrease in managerial power induced by a tightening in the outrage constraint due to the episode of financial distress