Chemical synthesis of monomeric self-sealant type esters Status report

Synthesis of alkyl esters of alpha-cyanosorbic acid for self-sealing polymerizatio

Results of the pretest analysis of the Apollo SM-LM RCS engine when operated at severe off-limits test conditions

Pretest analyses of Apollo SM-LM RCS engine to predict component failure effects on engine performanc

Shifting the paradigm on cultural property and heritage in international law and armed conflict: time to talk about reparations?

The demolition of the mausoleums in Timbuktu, the destruction of the Temple of Bel in Palmyra, and the aerial bombardment of the Old City of Sana’a in Yemen - each mark a continuing trend of intentionally targeting cultural property, and disregard for its protection under international humanitarian law. From as far back as records of war exist, through to contemporary conflicts, cultural sites have been a target for states and non-state armed groups. The destruction is used as a means to delegitimise opponents and displace their populations, reject the symbols of a regime, disrupt a sense of continuity for communities and corrode collective identities. (Brosché et al. 2017 & Ascherson 2005) While international law has focused on a three-P approach (hereafter ‘PPP’), imposing obligations on states to preserve, protect and prosecute the destruction of cultural property, treaties in this area remain silent on the aftermaths of such violence with little attention to reconstruction or reparative measures, thus further endangering sites. Moreover, such treaties emphasise the physical and properterial manifestations of heritage, neglecting its more intangible manifestations that are equally destroyed – such as language and traditions, oral history, songs and dance. As a result there is a vast lacuna in addressing the real impact of war on communities whose cultural heritage, and through it the cultural bonds between individuals and across generations, is destroyed.AHR

Electron temperatures during rapid subauroral ion drift events

International audienceExamples of data from DE-2 satellite instruments are presented. These illustrate the behaviour of plasma parameters in the F-region and adjacent topside ionosphere during rapid sub-auroral ion drift (SAID) events. In particular, a variety of behaviours of the electron temperature (Te) is demonstrated, both within and equatorward of the SAID region. The Sheffield University plasmasphere-ionosphere model (SUPIM) is used to perform calculations in which a model SAID is applied to a plasma flux tube. The model results indicate that strongly elevated ion temperature (a recognised signature of SAID events) is on occasion sufficient to raise Te to observed values by ion-electron heat transfer. On other occasions, an additional heat source is required. It is suggested that such a source for the electron gas may be due to interaction between the ring current and the plasmasphere at high altitudes. The magnitude of the downward heat flux is consistent with that necessary to produce sub-auroral red arcs. The resulting strongly heated electron gas causes vibrational excitation of molecular nitrogen in the thermosphere

The Shape and Scale of Galactic Rotation from Cepheid Kinematics

A catalog of Cepheid variables is used to probe the kinematics of the Galactic disk. Radial velocities are measured for eight distant Cepheids toward l = 300; these new Cepheids provide a particularly good constraint on the distance to the Galactic center, R_0. We model the disk with both an axisymmetric rotation curve and one with a weak elliptical component, and find evidence for an ellipticity of 0.043 +/- 0.016 near the Sun. Using these models, we derive R_0 = 7.66 +/- 0.32 kpc and v_circ = 237 +/- 12 km/s. The distance to the Galactic center agrees well with recent determinations from the distribution of RR Lyrae variables, and disfavors most models with large ellipticities at the solar orbit.Comment: 36 pages, LaTeX, 10 figure

Cepheid variables in the LMC cluster NGC 1866. I. New BVRI CCD photometry

We report BV(RI)c CCD photometric data for a group of seven Cepheid variables in the young, rich cluster NGC 1866 in the Large Magellanic Cloud. The photometry was obtained as part of a program to determine accurate distances to these Cepheids by means of the infrared surface brightness technique, and to improve the LMC Cepheid database for constructing Cepheid PL and PLC relations. Using the new data together with data from the literature, we have determined improved periods for all variables. For five fundamental mode pulsators, the light curves are now of excellent quality and will lead to accurate distance and radius determinations once complete infrared light curves and radial velocity curves for these variables become available.Comment: To appear in ApJ Supp., AASTeX, 24 pages, 8 tables, 8 figure