Observations of speciated atmospheric mercury at three sites in Nevada: Evidence for a free tropospheric source of reactive gaseous mercury

Air mercury (Hg) speciation was measured for 11 weeks (June–August 2007) at three sites simultaneously in Nevada, USA. Mean reactive gaseous Hg (RGM) concentrations were elevated at all sites relative to those reported for locations not directly influenced by known point sources. RGM concentrations at all sites displayed a regular diel pattern and were positively correlated with ozone (O3) and negatively correlated with elemental Hg (Hg0) and dew point temperature (Tdp). Superimposed on the diel changes were 2- to 7-day periods when RGM concentrations increased across all three sites, producing significant intersite correlations of RGM daily means (r = 0.53–0.76, p \u3c 0.0001). During these periods, enhanced O3 concentrations and lower Tdp were also observed. Back trajectories were applied to develop gridded frequency distribution (GFD) plots and determine trajectory residence times (TRT) in specific source boxes. The GFD for the upper-quartile RGM daily means at one site showed a contributing airflow regime from the high-altitude subtropics with little precipitation, while that developed for the lower-quartile RGM concentrations indicated predominantly lower-altitude westerly flow and precipitation. Daily mean TRT in a subtropical high-altitude source box (\u3e2 km and \u3c35°N) explained a component of the daily mean RGM at two sites (r2 = 0.37 and 0.27, p\u3c0.05). These observations indicate that long-range transport of RGM from the free troposphere is a potentially important component of Hg input to rural areas of the western United States

An Updated Review of Atmospheric Mercury

The atmosphere is a key component of the biogeochemical cycle of mercury, acting as a reservoir, transport mechanism, and facilitator of chemical reactions. The chemical and physical behavior of atmospheric mercury determines how, when, and where emitted mercury pollution impacts ecosystems. In this review, we provide current information about what is known and what remains uncertain regarding mercury in the atmosphere. We discuss new ambient, laboratory, and theoretical information about the chemistry of mercury in various atmospheric media. We review what is known about mercury in and on solid- and liquid-phase aerosols. We present recent findings related to wet and dry deposition and spatial and temporal trends in atmospheric mercury concentrations. We also review atmospheric measurement methods that are in wide use and those that are currently under development

2020 Media Futures

What will our media and entertainment be like in 2020

PI in the sky: The astronaut science advisor on SLS-2

The Astronaut Science Advisor (ASA, also known as Principal-Investigator-in-a-Box) is an advanced engineering effort to apply expert systems technology to experiment monitoring and control. Its goal is to increase the scientific value of information returned from experiments on manned space missions. The first in-space test of the system will be in conjunction with Professor Larry Young's (MIT) vestibulo-ocular 'Rotating Dome' experiment on the Spacelab Life Sciences 2 mission (STS-58) in the Fall of 1993. In a cost-saving effort, off-the-shelf equipment was employed wherever possible. Several modifications were necessary in order to make the system flight-worthy. The software consists of three interlocking modules. A real-time data acquisition system digitizes and stores all experiment data and then characterizes the signals in symbolic form; a rule-based expert system uses the symbolic signal characteristics to make decisions concerning the experiment; and a highly graphic user interface requiring a minimum of user intervention presents information to the astronaut operator. Much has been learned about the design of software and user interfaces for interactive computing in space. In addition, we gained a great deal of knowledge about building relatively inexpensive hardware and software for use in space. New technologies are being assessed to make the system a much more powerful ally in future scientific research in space and on the ground

LSQ13ddu: a rapidly evolving stripped-envelope supernova with early circumstellar interaction signatures

This paper describes the rapidly evolving and unusual supernova LSQ13ddu, discovered by the La Silla-QUEST survey. LSQ13ddu displayed a rapid rise of just 4.8 ± 0.9 d to reach a peak brightness of −19.70 ± 0.02 mag in the LSQgr band. Early spectra of LSQ13ddu showed the presence of weak and narrow HeI features arising from interaction with circumstellar material (CSM). These interaction signatures weakened quickly, with broad features consistent with those seen in stripped-envelope SNe becoming dominant around two weeks after maximum. The narrow HeI velocities are consistent with the wind velocities of luminous blue variables but its spectra lack the typically seen hydrogen features. The fast and bright early light curve is inconsistent with radioactive ⁵⁶Ni powering but can be explained through a combination of CSM interaction and an underlying ⁵⁶Ni decay component that dominates the later time behaviour of LSQ13ddu. Based on the strength of the underlying broad features, LSQ13ddu appears deficient in He compared to standard SNe Ib

Fatal child maltreatment in England, 2005-9

Objective: This paper presents comprehensive and up-to-date data covering four years of Serious Case Reviews into fatal child maltreatment in England. Methods: Information on all notified cases of fatal maltreatment between April 2005 and March 2009 was examined to obtain case characteristics related to a systemic classification of five broad groups of maltreatment deaths (severe physical assaults; covert homicide/infanticide; overt homicide; extreme neglect/deprivational abuse; deaths related to but not directly caused by maltreatment). Results: A total of 276 cases was recorded giving an incidence of 0.63 cases per 100,000 children (0-17) per year. 246 cases could be classified based on the data available. Of these the commonest specific group was those children who died as a result of severe physical assaults. Apparently deliberate overt and covert homicide was less common, whilst deaths as a direct consequence of neglect were rare. In contrast, some evidence of neglect was found in at least 40% of all cases, though not the direct cause of death. Conclusions: Class characteristics differ between the different categories of death and may suggest the need for different strategies for prevention

2020 media futures trends package

2020 Media Futures is a mul6-­‐industry strategic foresight project designed to understand and envision what media may look like in the year 2020; what kind of cross-­‐plaAorm Internet environment may shape our media and entertainment in the coming decade; and how Ontario firms take ac6on today toward capturing and maintaining posi6ons of na6onal and interna6onal leadership. The project asks: In the face of sweeping and disrupDve changes driven by the Internet, how can we help companies in the book, film, interacDve, magazine, music and television industries – Ontario’s CreaDve and Entertainment Cluster – to beNer idenDfy emerging opportuniDes, create more resilient strategic plans and partnerships, boost innovaDon, and compete in increasingly demanding global markets? This document is a product of our ‘horizon scanning’ process. Trends and Countertrends represent direcDonal paNerns in data, a rising Dde of signals, in which, for example, a criDcal mass of headlines about people using Facebook to call for help in emergency situaDons points to a larger trend regarding the increasing mission-­‐criDcal importance of social networks. To date we have idenDfied more than sixty trends at the project website: hNp://2020mediafutures.ca/Trend

Shallow-water scleractinian corals of Ascension Island, Central South Atlantic

The presence of five shallow-water scleractinian species at Ascension Island is confirmed, i.e. Favia gravida, Madracis sp., Siderastrea radians, Polycyathus atlanticus and Rhizosmilia gerdae. The three former are zooxanthellate, the two latter azooxanthellate. A sixth species, Cladocora debilis (azooxanthellate), dredged from moderately deep water is also expected to occur in shallow water. Madracis sp. and P. atlanticus are new records for the island. A previous record of Astrangia solitaria at Ascension is now referred to as P. atlanticus. Favia gravida, S. radians and C. debilis are amphi-Atlantic. Rhizosmilia gerdae is currently known only from Ascension Island and the Western Atlantic. None of the species are endemic to Ascension Island. No member of the family Dendrophylliidae has as yet been found at Ascension, whereas that family is represented at its nearest neighbour, St Helena Island.Darwin Initiative [EIDCF012]; Regional Council of Brittany; European Funds (ERDF); 'Laboratoire d'Excellence' LabexMER [ANR-10-LABX-19]; French government under the programme 'Investissements d'Avenir'info:eu-repo/semantics/publishedVersio