A posteriori error estimates for the Electric Field Integral Equation on polyhedra

We present a residual-based a posteriori error estimate for the Electric Field Integral Equation (EFIE) on a bounded polyhedron. The EFIE is a variational equation formulated in a negative order Sobolev space on the surface of the polyhedron. We express the estimate in terms of square-integrable and thus computable quantities and derive global lower and upper bounds (up to oscillation terms).Comment: Submitted to Mathematics of Computatio

Kinetic equations for Stark line shapes

The BBGKY formalism is revisited in the framework of plasma spectroscopy. We address the issue of Stark line shape modeling by using kinetic transport equations. In the most simplified treatment of these equations, triple correlations between an emitter and the perturbing charged particles are neglected and a collisional description of Stark effect is obtained. Here we relax this assumption and retain triple correlations using a generalization of the Kirkwood truncature hypothesis to quantum operator. An application to hydrogen lines is done in the context of plasma diagnostic, and indicates that the neglect of triple correlations can lead to a significant overestimate of the line width.Comment: 13 pages, 1 figur

A Program Evaluation: Fidelity of Implementation of the Wilson Reading System in A Mid-Atlantic School District

Reading is at the heart of education and it is the basic skill upon which all others are built. Reading difficulties underlie much of the differences in academic achievement between students with specific learning disabilities in reading and non-disabled students; addressing these challenges when children are young is the key for long-term success (Borman, 2005; Cortiella & Horowitz, 2014; Juel, 1988; National Reading Panel, 2000; Torgesen et al., 2001). The purpose of this mixed methods program evaluation was to provide information to stakeholders about the implementation of the Wilson Reading System in the Mid Atlantic School Division (MASD). By examining the fidelity of implementation of the current program used in MASD’s eight of the nine elementary schools and the three middle schools, the evaluator sought to determine the fidelity of implementation as compared to the Wilson Reading System recommended implementation methods by collecting data using a teacher interview protocol and data document reviews. Data showed inconsistencies in both Phase 1 and Phase 2 implementations. Additionally, the evaluator examined assessment data to identify students that successfully completed the program according to WADE post-assessment scores and examined that student’s grade level VSOL reading score to determine if the student is able to master the grade level content after successfully exiting the program. Findings showed fidelity of implementation is vital to determine the impact linked to student outcomes in this study. Recommendations for future research and continuous program improvement included implementing fidelity checks using district personnel, implementing on-going training and a robust data collection system, and implementing reliability and validity measures of the WADE

Femtosecond x-ray absorption spectroscopy of spin and orbital angular momentum in photoexcited Ni films during ultrafast demagnetization

We follow for the first time the evolution of the spin and orbital angular momentum of a thin Ni film during ultrafast demagnetization, by means of x-ray magnetic circular dichroism. Both components decrease with a 130 +/- 40 fs time constant upon excitation with a femtosecond laser pulse. Additional x-ray absorption measurements reveal an increase in the spin-orbit interaction by 6 +/- 2 % during this process. This is the experimental demonstration quantifying the importance of spin-orbit mediated processes during the demagnetization

Commissioning of the cryogenic safety test facility PICARD

The sizing of cryogenic safety relief devices requires detailed knowledge on the evolution of the pressure increase in cryostats following hazardous incidents such as the venting of the insulating vacuum with atmospheric air. Based on typical design and operating conditions in liquid helium cryostats, the new test facility PICARD, which stands for Pressure Increase in Cryostats and Analysis of Relief Devices, has been constructed. The vacuum-insulated test stand has a cryogenic liquid volume of 100 liters and a nominal design pressure of 16 bar(g). This allows a broad range of experimental conditions with cryogenic fluids. In case of helium, mass flow rates through safety valves and rupture disks up to about 4 kg/s can be measured. Beside flow rate measurements under various conditions (venting diameter, insulation, working fluid, liquid level, set pressure), the test stand will be used for studies on the impact of two-phase flow and for the measurement of flow coeffcients of safety devices at low temperature. This paper describes the operating range, layout and instrumentation of the test stand and presents the status of the commissioning phase

Mesenchymal Stem Cells and Inflammatory Cardiomyopathy: Cardiac Homing and Beyond

Under conventional heart failure therapy, inflammatory cardiomyopathy usually has a progressive course, merging for alternative interventional strategies. There is accumulating support for the application of cellular transplantation as a strategy to improve myocardial function. Mesenchymal stem cells (MSCs) have the advantage over other stem cells that they possess immunomodulatory features, making them attractive candidates for the treatment of inflammatory cardiomyopathy. Studies in experimental models of inflammatory cardiomyopathy have consistently demonstrated the potential of MSCs to reduce cardiac injury and to improve cardiac function. This paper gives an overview about how inflammation triggers the functionality of MSCs and how it induces cardiac homing. Finally, the potential of intravenous application of MSCs by inflammatory cardiomyopathy is discussed