Mass and density of B-type asteroid (702) Alauda

Observations with the adaptive optics system on the Very Large Telescope reveal that outer main belt asteroid (702) Alauda has a small satellite with primary to secondary diameter ratio of $\sim$56. The secondary revolves around the primary in 4.9143 $\pm$ 0.007 days at a distance of 1227 $\pm$ 24 km, yielding a total system mass of (6.057 $\pm$ 0.36) $\times$ 10$^{18}$ kg. Combined with an IRAS size measurement, our data yield a bulk density for this B-type asteroid of 1570 $\pm$ 500 kg~m$^{-3}$.Comment: In press, ApJ 2011. 6 pages, 4 figure

Transforming Possible Risk Into Certain Harm: A Critical Interpretive Synthesis of the Literature on Perinatal Cannabis Use

Substance use in pregnancy has been a prominent public health concern for the last several decades. Since the legalization of cannabis in Canada and across several American states, cannabis use during pregnancy has gained considerable public health, scientific, and media attention. This critical interpretive synthesis explores how the problem of cannabis use in pregnancy is constructed in the scientific literature and illuminates clinical, social, and political responses this construction engenders. The state of empirical evidence regarding the impact of perinatal cannabis use is fraught; a number of studies, of variable quality, have found no associations between cannabis use and adverse neonatal outcomes, while others have found cannabis to be associated with low birthweight and prematurity among other risks. Despite the inconsistent nature of the evidence base, the literature is underpinned by two important assumptions: prenatal cannabis exposure is an asocial phenomenon that can be disentangled from the social determinants of health, and cannabis exposure has detrimental effects on fetal and neonatal health. These assumptions shape indicators of signal and noise in the data by influencing the significance ascribed to particular findings, producing patterns of data interpretation that ultimately transform evidence of potential harms into certain risks and creates the mirage of a cohesive, unambiguous evidence base. We argue that the way that cannabis use in pregnancy is framed as a scientific and public health problem in the literature contributes to the stigmatization of pregnant people who use substances. We caution that failure to consider the interplay between environment, resources and other social determinants of health may ultimately cause undue harm to families and foreclose opportunities for investments that may promote health and well-being

Softening of the insulating phase near Tc for the photo-induced insulator-to-metal phase transition in vanadium dioxide

We use optical-pump terahertz-probe spectroscopy to investigate the near-threshold behavior of the photoinduced insulator-to-metal (IM) transition in vanadium dioxide thin films. Upon approaching Tc a reduction in the fluence required to drive the IM transition is observed, consistent with a softening of the insulating state due to an increasing metallic volume fraction (below the percolation limit). This phase coexistence facilitates the growth of a homogeneous metallic conducting phase following superheating via photoexcitation. A simple dynamic model using Bruggeman effective medium theory describes the observed initial condition sensitivity.Comment: accepted for publication in Physical Review Letter

S13RS SGR No. 13 (Sustainability Orientation)

A RESOLUTION To urge and request the Office of Orientation to implement a sustainability program in all new student orientation session

The Impact of Conservation on the Status of the World\u27s Vertebrates

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world\u27s vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the main drivers of biodiversity loss in these groups: agricultural expansion, logging, overexploitation, and invasive alien species

TEMPO2, a new pulsar timing package. I: Overview

Contemporary pulsar timing experiments have reached a sensitivity level where systematic errors introduced by existing analysis procedures are limiting the achievable science. We have developed tempo2, a new pulsar timing package that contains propagation and other relevant effects implemented at the 1ns level of precision (a factor of ~100 more precise than previously obtainable). In contrast with earlier timing packages, tempo2 is compliant with the general relativistic framework of the IAU 1991 and 2000 resolutions and hence uses the International Celestial Reference System, Barycentric Coordinate Time and up-to-date precession, nutation and polar motion models. Tempo2 provides a generic and extensible set of tools to aid in the analysis and visualisation of pulsar timing data. We provide an overview of the timing model, its accuracy and differences relative to earlier work. We also present a new scheme for predictive use of the timing model that removes existing processing artifacts by properly modelling the frequency dependence of pulse phase.Comment: Accepted by MNRA

Accelerating the monitoring of global biodiversity : Revisiting the sampled approach to generating Red List Indices

Abstract Given the current biodiversity crisis, pragmatic approaches to detect global conservation trends across a broad range of taxa are critical. A sampled approach to the Red List Index (RLI) was proposed, as many groups are highly speciose. However, a decade after its conception, the recommended 900 species sample has only been implemented in six groups and trend data are available for none, potentially because this sample is unfeasibly high. Using a broader set of all available data we show that when re-assessments are conducted every 10 years, 200 species (400 in some cases) should be sufficient to detect a RLI trend. Correctly detecting changes in slope still requires samples of 900 species (11,000 in some cases). Sampled assessments can accelerate biodiversity monitoring and complement current metrics, but the time-period between assessments and the approaches? purpose should be carefully considered, as there is a trade-off between sample size and the resulting indices.Peer reviewe

Imaging Features of Gray-Scale and Contrast-Enhanced Color Doppler US for the Differentiation of Transient Renal Arterial Ischemia and Arterial Infarction

No publisher copyright information found in the SHERPA/RoMEO list.OBJECTIVE: To characterize the imaging features on gray-scale and contrast-enhanced color Doppler US images which differentiate renal ischemia from renal infarction. MATERIALS AND METHODS: The segmental renal arteries of eight healthy rabbits were surgically ligated. In four of these rabbits, the ligated renal artery was released 60 minutes after arterial occlusion to cause transient ischemia. In the remaining four rabbits, the arterial ligation was retained to cause a permanent infarction. The gray-scale and contrast-enhanced color Doppler US imaging features of the involved renal parenchyma of both ischemia and infarction groups were compared with respect to the presence or absence of parenchymal swelling, echogenicity changes, tissue loss and perfusion defects. RESULTS: Parenchyma swelling, echogenic changes, tissue loss and perfusion defects were found to be more extensive in the infarction than the ischemia group. The hyperechoic areas reperfused with blood flow recovered normal echogenicity and perfusion, whereas the hyperechoic areas without reperfusion became renal infarcts. CONCLUSION: Gray-scale and contrast-enhanced color Doppler US showed that the hyperechoic areas with reperfusion may reverse to normal parenchyma and allow the differentiation of renal ischemia from renal infarction