Optical tracking systems typically trade off between astrometric precision and field of view. In this work, we showcase a networked approach to optical tracking using very wide field-of-view imagers that have relatively low astrometric precision on the scheduled OSIRIS-REx slingshot manoeuvre around Earth on 22 Sep 2017. As part of a trajectory designed to get OSIRIS-REx to NEO 101955 Bennu, this flyby event was viewed from 13 remote sensors spread across Australia and New Zealand to promote triangulatable observations. Each observatory in this portable network was constructed to be as lightweight and portable as possible, with hardware based off the successful design of the Desert Fireball Network. Over a 4-h collection window, we gathered 15 439 images of the night sky in the predicted direction of the OSIRIS-REx spacecraft. Using a specially developed streak detection and orbit determination data pipeline, we detected 2 090 line-of-sight observations. Our fitted orbit was determined to be within about 10 km of orbital telemetry along the observed 109 262 km length of OSIRIS-REx trajectory, and thus demonstrating the impressive capability of a networked approach to Space Surveillance and Tracking.

This paper highlights unique sites in Ladakh, India, investigated during our 2016 multidisciplinary pathfinding expedition to the region. We summarize our scientific findings and the site's potential to support science exploration, testing of new technologies and science protocols within the framework of astrobiology research. Ladakh has several accessible, diverse, pristine and extreme environments at very high altitudes (3000–5700 m above sea level). These sites include glacial passes, sand dunes, hot springs and saline lake shorelines with periglacial features. We report geological observations and environmental characteristics (of astrobiological significance) along with the development of regolith-landform maps for cold high passes. The effects of the diurnal water cycle on salt deliquescence were studied using the ExoMars Mission instrument mockup: HabitAbility: Brines, Irradiance and Temperature (HABIT). It recorded the existence of an interaction between the diurnal water cycle in the atmosphere and salts in the soil (which can serve as habitable liquid water reservoirs). Life detection assays were also tested to establish the best protocols for biomass measurements in brines, periglacial ice-mud and permafrost melt water environments in the Tso-Kar region. This campaign helped confirm the relevance of clays and brines as interest targets of research on Mars for biomarker preservation and life detection.

Radiocarbon dating of marine samples requires a local marine reservoir correction, or ΔR value, for accurate age calibrations. For the Samoan Archipelago in the central Pacific, ΔR values have been proposed previously, but, unlike some Polynesian archipelagoes, ΔR values seem not to vary spatially and temporally. Here, we demonstrate such variability by reporting a ΔR of –101±72 ΔR for the Manu‘a Group—the eastern-most islands in the archipelago—for the colonization period. This value is based on accelerator mass spectrometry (AMS) 14C and uranium-thorium (U-Th) series dating of individual coral branches from pre-2300 cal BP archaeological contexts. This figure differs from the previously proposed modern ΔR of 28±26 yr derived from dated historic, pre-1950, shell samples from the western islands of Samoa. Consequently, we recommend using the ΔR of –101±72 yr for the 1st millennium BC in Manu‘a, and 28±26 yr for calibrating dates within the 2nd millennium AD in the western islands (Savai‘i to Tutuila). Until more data from across the archipelago and from throughout the entire culture-historical sequence document ΔR variability, we recommend that researchers use both of these ΔR values to evaluate how the dates of marine-derived samples compare with AMS dates on identified, short-lived wood charcoal.

The objective of the study was to test the hypothesis that changes in arm anthropometry can be used to determine the risk of faltering growth in twin gestations. Serial data on midupper arm circumference (MUAC) and maternal weight gain were collected from a sample of 156 mothers. Changes in MUAC were monitored from 20 to 34 weeks. Women with a large loss of MUAC (greater than 1.5 cm), particularly when it occurred within two to four weeks of delivery, were significantly heavier, had higher pregravid Body Mass Indexes (BMIs), but gained less weight than mothers with no change in MUAC. In analysis of covariance models adjusting for length of gestation, black ethnicity, males per twin pair, monochorionicity, and baseline MUAC at 20 weeks, a large loss of MUAC was associated with significantly lower birthweight (2263 g vs. 2499 g) and birthweight z-score (–0.92 SDU vs. –0.39 SDU). Changes in MUAC from 20 to 34 weeks, and especially near delivery, are significantly associated with fetal growth in twin pregnancies. A positive change may indicate that the mother has adequate dietary intake or nutrient stores to continue to accrue lean body mass and support fetal growth, while a loss of MUAC indicates that dietary intake or nutrient stores may be inadequate. This simple, relatively precise, measure of change in maternal body composition during pregnancy may be useful in identifying twin pregnancies at risk for faltering intrauterine growth, particularly among overweight or obese women.

The objective of this study was to compare length of gestation, fetal growth, and birthweight by race/ethnicity and pregravid weight groups in twin pregnancies. Three thousand and thirty-six twin pregnancies of 28 weeks or more gestation were divided by race/ethnicity (White, Black and Hispanic), and pregravid body mass index (BMI) groups (less than 25.0 vs. 25.0 or more). Outcomes were modeled using multiple regression, controlling for confounders, with White non-Hispanic women as the reference group. Hispanic women had the highest average birthweight and the longest gestation, as well as the lowest proportions of low birthweight, very low birthweight, preterm and early preterm births of the 3 race/ethnicity groups. In the multivariate analyses, Hispanic women had significantly longer gestations (by 7.8 days) and faster rates of fetal growth midgestation (20 to 28 weeks, by 17.4 g/week) and late gestation (after 28 weeks, by 5.3 g/week), whereas Black women had significantly slower rates of fetal growth (by 5.7 g/week and by 4.5 g/week, respectively). These findings in twins reflect the racial and ethnic disparities previously shown in singletons, including the Hispanic paradox of longer gestations and higher rates of fetal growth.

A proposed merging of pathological gambling with the drug addictions in the forthcoming DSM-5 prompts an overview of the neurobiological data showing similarities between these conditions, as well as an update on national trends in gambling behaviour and current treatment provision.

Erbium dihydride Er(H,D,T)2 is a fluorite structure rare-earth dihydride useful for the storage of hydrogen isotopes in the solid state. However, thermodynamic predictions indicate that erbium oxide formation will proceed readily during processing, which may detrimentally contaminate Er(H,D,T)2 films. In this work, transmission electron microscopy (TEM) techniques including energy-dispersive x-ray spectroscopy, energy-filtered TEM, selected area electron diffraction, and high-resolution TEM are used to examine the manifestation of oxygen contamination in ErD2 thin films. An oxide layer ∼30–130 nm thick was found on top of the underlying ErD2 film, and showed a cube-on-cube epitaxial orientation to the underlying ErD2. Electron diffraction confirmed the oxide layer to be Er2O3. While the majority of the film was observed to have the expected fluorite structure for ErD2, secondary diffraction spots suggested the possibility of either nanoscale oxide inclusions or hydrogen ordering. In situ heating experiments combined with electron diffraction ruled out the possibility of hydrogen ordering, so epitaxial oxide nanoinclusions within the ErD2 matrix are hypothesized. TEM techniques were applied to examine this oxide nanoinclusion hypothesis.

Subarachnoid hemorrhage (SAH) survivors often report psychosocial and emotional changes, including a diminished capacity for decision making. However, systematic investigations into the nature of the changes have been limited to those patients surviving SAH secondary to aneurysms of the anterior communicating artery. This study aimed to explore the nature of decision making in survivors of SAH secondary to aneurysms of the middle cerebral or posterior communicating artery using a series of computerized tasks. Twenty SAH survivors and 20 matched controls completed a battery of computerized decision-making tasks. These included tasks examining an individual's ability to make probabilistic choices and risk-taking behavior, as well as tasks examining aspects of impulsivity. The results revealed two key patterns of abnormal decision-making behavior in the SAH survivors: altered sensitivity to both reward and punishment, and impulsive responding. These complex deficits may contribute to difficulties in daily living resulting from apathy, poor judgment, or inhibition in SAH survivors. (JINS, 2006, 12, 697–706.)