Refinements on the pinhole camera measurements of the LDEF attitude

The results from the University of Alabama in Huntsville (UAH) pinhole camera were reanalyzed to include the effects of corotation of the atmosphere with the Earth as well as satellite oscillation. Previous results from the instrument showed that the satellite had stable attitude offsets in yaw of 8.0 deg and 1.0 deg in pitch; these offsets are unchanged by the present analysis. The primary impact zone of oxygen, i.e., the directly exposed spot on a silver detector, had a ratio of major to minor axes equal to 1.05, which was interpreted as being caused by a small oscillation of plus or minus 0.35 degrees (with precision plus or minus 0.15 degrees). The present analysis shows that the observed effect can largely be accounted for by atmospheric corotation, but that an additional oscillation in yaw of the order of a degree cannot be excluded. The sensitivity of the pinhole camera to satellite oscillations is shown to decrease nonlinearly with decreasing magnitude of the oscillation and to vary inversely with the gas temperature

James Webb Space Telescope (JWST) Integrated Science Instruments Module (ISIM) Cryo-Vacuum (CV) Test Campaign Summary

JWST Integrated Science Instruments Module (ISIM) completed its system-level space simulation testing program at the NASA Goddard Space Flight Center (GSFC). In March 2016, ISIM was successfully delivered to the next level of integration with the Optical Telescope Element (OTE), to form OTIS (OTE + ISIM), after concluding a series of three cryo-vacuum (CV) tests. During these tests, the complexity of the mission has generated challenging requirements that demand highly reliable system performance and capabilities from the Space Environment Simulator (SES) vacuum chamber. The first test served as a risk reduction test; the second test provided the initial verification of the fully-integrated flight instruments; and the third test verified the system in its final flight configuration following mechanical environmental tests (vibration and acoustics). From one test to the next, shortcomings of the facility were uncovered and associated improvements in operational capabilities and reliability of the facility were required to enable the project to verify system-level requirements. This paper: (1) provides an overview of the integrated mechanical and thermal facility systems required to achieve the objectives of JWST ISIM testing, (2) compares the overall facility performance and instrumentation results from the three ISIM CV tests, and (3) summarizes lessons learned from the ISIM testing campaign

Pensions policy in the UK: An economic analysis

An attempt to unravel the complexities of pension policy in the UK, including financial, fiscal, labour-market and income-distribution analyses of the retirement-income system. This book, drawing on five years’ IFS research, was widely praised. A Financial Times editorial observed that ‘The IFS’s pioneering attempt to quantify the different returns to pensioners is welcome’. The Independent reported that ‘This book challenges the common assumption that personal pension plans are inherently more risky than occupational or state provision’.

Violence and frontier in twentieth century Native American literature

The central argument of my work is that authors Leslie Marmon Silko, Louis Owens, and Gerald Vizenor, working in the latter half of the twentieth century, use violence as a literary device (literary violence) for exposing and critiquing modes of systemic violence inherent in the formative originary myths of dominant US culture, specifically the mythic frontier and West. I argue that they engage with questions arising out of the systemic and normative violence required to sustain exceptionalist and supremacist Euramerican myth, which in turn sanitise the unspeakable violence of settler colonialism. This sanitising effect produces a form of transcendent violence, so called because the violence it describes is deemed to be justified in accordance with dominant ideology. In addressing this, Silko rewrites the mythic legacies of frontier and the West, rearticulating the unspeakable violence of conquest and domination, resulting in an anti-Western, pre-apocalyptic vision that turns away from European modernity and late twentieth century capitalism, looking instead to an Indigenous worldview. Owens similarly proposes an alternative reading of frontier where binaries of racial and cultural difference become malleable and diffuse, producing unexpected breaks with established ideology and narratives of dominance. The unseen systemic violence of the provincial town, in many ways the American societal idyll in microcosm, emerges during key confrontations between Native and non-Native characters in the liminal spaces and boundaries of the provincial town. Bringing these different threads together, Vizenor critiques systemic and institutionalised violence in his fiction and non-fiction work. His breakthrough novel Darkness in Saint Louis Bearheart shares key characteristics with the work of Silko and Owens in this regard. Transgressing borders of taste, binaries of simulated Indianness, and notions of Euramerican cultural dominance, Vizenor’s mocking laugh destabilises the notion of completed conquest and closed frontiers as the final word on Euramerican supremacy

Pensions policy in the UK: An economic analysis

An attempt to unravel the complexities of pension policy in the UK, including financial, fiscal, labour-market and income-distribution analyses of the retirement-income system. This book, drawing on five years’ IFS research, was widely praised. A Financial Times editorial observed that ‘The IFS’s pioneering attempt to quantify the different returns to pensioners is welcome’. The Independent reported that ‘This book challenges the common assumption that personal pension plans are inherently more risky than occupational or state provision’

A crystal/melt partitioning study for sulfur and halogens: pyroxenes as probes for assessing gas loads in LIP magmas

A link between magmatism from Large Igneous Provinces (LIPs) and mass extinctions has been observed at leastin five occasions in the Phanerozoic. Volatile species such as S, C and halogen compounds severely impactedthe global environment, released both from melts and thermal metamorphism of volatile-rich sediments. It is stillchallenging to obtain quantitative estimates of the degassed volatiles for ancient magmatic systems, particularly inthe absence of melt inclusions. We propose to fill the gap of knowledge on sulfur partitioning between mineralsand melts, at the aim of using phenocrysts as probes of volatile contents in the melts from which they crystallized.Measuring a volatile concentration in natural minerals (chiefly clinopyroxene) and combining it with an experi-mentally determined partition coefficient (KD), the volatile load in basaltic equilibrium melts can be calculated.We measured a clinopyroxene/melt sulfur KD of 0.0009\ub10.0001 for basaltic experiments performed at conditionstypical of LIP basalts (FMQ-2; 800-1000 MPa; 1000 \u30a-1350 \u30aC), through ion microprobe (Nordsim). Basaltic ex-periments were also simultaneously analyzed for Cl and F. For these elements the measured clinopyroxene/meltKDs were more variable, 0.0071\ub10.0052 and 0.1985\ub10.087, respectively. Compatibility of sulfur, chlorine andfluorine in clinopyroxene from basaltic systems is markedly different (F>Cl>S), in agreement with what observedby previous studies, and the partition coefficient is well constrained around 0.001 for S. Application of the newlymeasured sulfur KD to samples from thoroughly-dated lava piles from the Deccan Traps and from the SiberianTraps sills reveal that most of the basalts were at or near sulfide saturation (up to ca. 2000 ppm for low fO2melts)

Pensions policy in the UK: An economic analysis

An attempt to unravel the complexities of pension policy in the UK, including financial, fiscal, labour-market and income-distribution analyses of the retirement-income system. This book, drawing on five years’ IFS research, was widely praised. A Financial Times editorial observed that ‘The IFS’s pioneering attempt to quantify the different returns to pensioners is welcome’. The Independent reported that ‘This book challenges the common assumption that personal pension plans are inherently more risky than occupational or state provision’

Multiple subduction imprints in the mantle below Italy detected in a single lava flow

Post-collisional magmatism reflects the regional subduction history prior to collision but the link between the two is complex and often poorly understood. The collision of continents along a convergent plate boundary commonly marks the onset of a variety of transitional geodynamic processes. Typical responses include delamination of subducting lithosphere, crustal thickening in the overriding plate, slab detachment and asthenospheric upwelling, or the complete termination of convergence. A prominent example is the Western-Central Mediterranean, where the ongoing slow convergence of Africa and Europe (Eurasia) has been accommodated by a variety of spreading and subduction systems that dispersed remnants of subducted lithosphere into the mantle, creating a compositionally wide spectrum of magmatism. Using lead isotope compositions of a set of melt inclusions in magmatic olivine crystals we detect exceptional heterogeneity in the mantle domain below Central Italy, which we attribute to the presence of continental material, introduced initially by Alpine and subsequently by Apennine subduction. We show that superimposed subduction imprints of a mantle source can be tapped during a melting episode millions of years later, and are recorded in a single lava flow

Resveratrol Inhibits KSHV Reactivation by Lowering the Levels of Cellular EGR-1

In the field of herpesvirus research, the exact molecular mechanism by which such viruses reactivate from latency remains elusive. Kaposi's sarcoma-associated herpesvirus (KSHV) primarily exists in a latent state, while only 1–3% of cells support lytic infection at any specific time. KSHV reactivation from latency is an exceedingly intricate process mediated by the integration of viral and cellular factors. Previously, our lab has described early growth response-1 (Egr-1) as an essential component for the KSHV reactivation process via its ability to mediate transcription of KSHV ORF50, the gene encoding for replication and transcription activator (RTA), a viral component known to control the switch from latent to lytic infection. In here, electrophoretic mobility shift assays (EMSA) and chromatin immunoprecipitation (ChIP) experiments revealed that Egr-1 binds KSHV ORF50 promoter (ORF50P) in at least two different GC-rich binding domains. Expression profiles of cellular egr-1 and KSHV-encoded ORF50 follow a similar pattern during de novo KSHV infection. Over-expressing Egr-1, a signaling component downstream of Raf>MEK>ERK1/2, in KSHV-infected cells activates KSHV lytic replication. Through performing more physiologically relevant experiments, we analyzed the effect of a dietary supplement containing resveratrol on KSHV-infected cells. Our results, for the first time, demonstrate resveratrol to act in lowering ERK1/2 activity and expression of Egr-1 in KSHV-infected cells, resulting in the suppression of virus reactivation from latency. Taken together, these findings will undoubtedly contribute to future studies on not only combating KSHV related disease conditions, but also on other herpesviruses-induced pathogenesis