Abundance variations and first ionization potential trends during large stellar flares

The Solar First Ionization Potential (FIP) effect, where low-FIP elements are enriched in the corona relative to the photosphere, while high-FIP abundances remain unchanged, has been known for a long while. High resolution X-ray spectroscopy has revealed that active stellar coronae show an opposite effect, which was labeled the Inverse-FIP (IFIP) effect. The correlation found between coronal activity and the FIP/IFIP bias suggested perhaps that flaring activity is involved in switching from FIP to IFIP. This work aims at a more systematic understanding of the FIP trends during stellar flares and complements an earlier study based on Chandra alone. The eight brightest X-ray flares observed with XMM-Newton are analyzed and compared with their respective quiescence states. Together with six previous flares observed with Chandra, this establishes the best currently available sample of flares. We look for abundance variations during the flare and their correlation with FIP. For that purpose, we define a new FIP bias measure. A trend is found where coronae that are IFIP biased in quiescence, during flares show a FIP bias with respect to their quiescence composition. This effect is reversed for coronae that are FIP biased in quiescence. The observed trend is thus consistent with chromospheric evaporation rather than with a FIP mechanism operating during flares. It also suggests that the quiescent IFIP bias is real and that the large flares are not the direct cause of the IFIP effect in stellar coronae.Comment: 12 pages, 6 figures, submitted to A&

Grantmaker's Guide: Strengthening International Indigenous Philanthropy

As members of International Funders for Indigenous Peoples (IFIP), we are anxious to grow the field and bring an infusion of new faces, sources of investment and expertise, along with the professional camaraderie that grows from shared commitment and passion. IFIP is an affinity group of the Council on Foundations dedicated to assembling international grantmakers in support of Indigenous philanthropies and fostering funding partnerships to improve the lives of Indigenous People globally. Over the past decade, IFIP has convened conferences and workshops that catalyze thoughtful, engaged collaboration among participants.Experienced donors recognize the resilience of Indigenous Peoples, often in the face of overwhelming odds and continual attacks on many fronts. Their diversity and creativity is an essential resource for the future of our planet. There is important work of global significance underway. Nevertheless, there are technical challenges that this guide can help identify and overcome. Many standard practices simply won't work. We need to be on the ground listening to people and stretching our imaginations. We cannot wait for the 'experts' to send us polished proposals that meet our criteria and timetables. Truly effective philanthropy has always relied on ingenuity and creative paths of understanding to effect deep change in the world.We can embrace and drive this change. This guide describes the practical experiences of those pioneers who have forged ahead

Securing Information-Centric Networking without negating Middleboxes

Information-Centric Networking is a promising networking paradigm that overcomes many of the limitations of current networking architectures. Various research efforts investigate solutions for securing ICN. Nevertheless, most of these solutions relax security requirements in favor of network performance. In particular, they weaken end-user privacy and the architecture's tolerance to security breaches in order to support middleboxes that offer services such as caching and content replication. In this paper, we adapt TLS, a widely used security standard, to an ICN context. We design solutions that allow session reuse and migration among multiple stakeholders and we propose an extension that allows authorized middleboxes to lawfully and transparently intercept secured communications.Comment: 8th IFIP International Conference on New Technologies, Mobility & Security, IFIP, 201

IFIP TC8 information systems : Conception, birth and early years

The paper begins by discussing the conception and birth of IFIP TC8 in Amsterdam in 1975 and 1976, describing the roles of the main players (such as IFIP and IFIP ADP). The background in terms of the IFIP organization and its already extant technical committees is reviewed. The birth pains associated with IFIP TC8’s early existence are also explained. The early meetings of TC8 and its Working Groups are discussed. From 1976 to 1986 formally planned events are discussed, with emphasis on the driving forces influencing the TC8 decision process throughout thiese years. The second half of this paper then reviews the background in the IT world (outside IFIP) as it prevailed in the period leading up to 1976. This backgound is examined in terms the of software and hardware technology of the timeThe past and the future of information systems: 1976-2006 and beyondRed de Universidades con Carreras en Informática (RedUNCI

Convergence of optimal control problems governed by second kind parabolic variational inequalities

We consider a family of optimal control problems where the control variable is given by a boundary condition of Neumann type. This family is governed by parabolic variational inequalities of the second kind. We prove the strong convergence of the optimal controls and state systems associated to this family to a similar optimal control problem. This work solves the open problem left by the authors in IFIP TC7 CSMO2011