Observing the sky at extremely high energies with the Cherenkov Telescope Array: Status of the GCT project

The Cherenkov Telescope Array is the main global project of ground-based gamma-ray astronomy for the coming decades. Performance will be significantly improved relative to present instruments, allowing a new insight into the high-energy Universe [1]. The nominal CTA southern array will include a sub-array of seventy 4 m telescopes spread over a few square kilometers to study the sky at extremely high energies, with the opening of a new window in the multi-TeV energy range. The Gamma-ray Cherenkov Telescope (GCT) is one of the proposed telescope designs for that sub-array. The GCT prototype recorded its first Cherenkov light on sky in 2015. After an assessment phase in 2016, new observations have been performed successfully in 2017. The GCT collaboration plans to install its first telescopes and cameras on the CTA site in Chile in 2018-2019 and to contribute a number of telescopes to the subsequent CTA production phase.Comment: 8 pages, 7 figures, ICRC201

Resistive Switching Assisted by Noise

We extend results by Stotland and Di Ventra on the phenomenon of resistive switching aided by noise. We further the analysis of the mechanism underlying the beneficial role of noise and study the EPIR (Electrical Pulse Induced Resistance) ratio dependence with noise power. In the case of internal noise we find an optimal range where the EPIR ratio is both maximized and independent of the preceding resistive state. However, when external noise is considered no beneficial effect is observed.Comment: To be published in "Theory and Applications of Nonlinear Dynamics: Model and Design of Complex Systems", Proceedings of ICAND 2012 (Springer, 2013

Nonlinear instability of density-independent orbital-free kinetic energy functionals

We study in this article the mathematical properties of a class of orbital-free kinetic energy functionals. We prove that these models are linearly stable but nonlinearly unstable, in the sense that the corresponding kinetic energy functionals are not bounded from below. As a matter of illustration, we provide an example of an electronic density of simple shape the kinetic energy of which is negative.Comment: 14 pages, 1 figur

French space activities

The four main points of research and development of space programs by France are explained. The National Center of Space Studies is discussed, listing the missions of the Center and describing the activities of the staff

Human resources for control of tuberculosis and HIV-associated tuberculosis.

The global targets for tuberculosis (TB) control were postponed from 2000 to 2005, but on current evidence a further postponement may be necessary. Of the constraints preventing these targets being met, the primary one appears to be the lack of adequately trained and qualified staff. This paper outlines: 1) the human resources and skills for global TB and human immunodeficiency virus (HIV) TB control, including the human resources for implementing the DOTS strategy, the additional human resources for implementing joint HIV-TB control strategies and what is known about human resource gaps at global level; 2) the attempts to quantify human resource gaps by focusing on a small country in sub-Saharan Africa, Malawi; and 3) the main constraints to human resources and their possible solutions, under six main headings: human resource planning; production of human resources; distribution of the work-force; motivation and staff retention; quality of existing staff; and the effect of HIV/AIDS. We recommend an urgent shift in thinking about the human resource paradigm, and exhort international policy makers and the donor community to make a concerted effort to bridge the current gaps by investing for real change

An Examination of High School Intra-District Funding in Two Virginia School Divisions

Most states allocate education funds by grant or category at the district level, and most districts distribute funds at the school level. 1 Differences between allocations from the states to the districts and distribution methods from the districts to the schools can lead to unintended consequences in funding equity. This may undermine the purpose of the funding policies developed by state legislatures. Most states use a formula that provides a foundation funding amount to the district for each student. In addition, most states typically provide supplementary categorical funding to the district based on demographic characteristics of students (such as free and reduced lunch eligibility, English language learner, etc.), which, theoretically, increases the level of services needed and, therefore, the cost of educating those students.2 The distribution of these categorical funds and tracking of money occur only at the district level, so no evidence exists to show that money is reaching the schools or students who need it most. This analysis explores intra-district spending and resource distribution within two school divisions in Virginia to determine what, if any, inequities exist. The researcher adapted Berne and Stiefel\u27s (1984) inter-district framework in which three equity concepts were examined: horizontal equity, vertical equity, and equal opportunity. Once the researcher obtained the financial and descriptive information about the two divisions and the high schools within those divisions, the researcher further examined the schools with the highest and the lowest percentage of students living in poverty (indexed by participation in the federal free and reduced-price lunch program). The study found that while average class size varies to some extent among the schools, there are important differences in teacher quality, curriculum, equipment, and supplies. Even though this study was limited in its sample size, the implications, and the opportunities are far reaching. If low-SES children have the proper support and understanding, financial status does not have to be the ultimate determinant of academic achievement

Evolution of damage during the fatigue of 3D woven glass-fibre reinforced composites subjected to tension-tension loading observed by time-lapse X-ray tomography

The development of fatigue damage in a glass fibre modified layer-to-layer three dimensional (3D) woven composite has been followed by time-lapse X-ray computed tomography (CT). The damage was found to be distributed regularly throughout the composite according to the repeating unit, even at large fractions of the total life. This suggests that the through-thickness constraint provides a high level of stress redistribution and damage tolerance. The different types of damage have been segmented, allowing a quantitative analysis of damage evolution as a function of the number of fatigue cycles. Transverse cracks were found to initiate within the weft after just 0.1% of life, followed soon after (by 1% of life) by longitudinal debonding cracks. The number and extent of these multiplied steadily over the fatigue life, whereas the spacing of transverse cracks along with weft/binder debonding saturated at 60% of life and damage in the resin pockets occurred only just before final failure