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Limitations of access have long restricted exploration and investigation of the cavities beneath ice shelves to a small number of drillholes. Studies of sea-ice underwater morphology are limited largely to scientific utilization of submarines. Remotely operated vehicles, tethered to a mother ship by umbilical cable, have been deployed to investigate tidewater-glacier and ice-shelf margins, but their range is often restricted. The development of free-flying autonomous underwater vehicles (AUVs) with ranges of tens to hundreds of kilometres enables extensive missions to take place beneath sea ice and floating ice shelves. Autosub2 is a 3600 kg, 6.7 m long AUV, with a 1600 m operating depth and range of 400 km, based on the earlier Autosub1 which had a 500 m depth limit. A single direct-drive d.c. motor and five-bladed propeller produce speeds of 1–2 m s−1. Rear-mounted rudder and stern-plane control yaw, pitch and depth. The vehicle has three sections. The front and rear sections are free-flooding, built around aluminium extrusion space-frames covered with glass-fibre reinforced plastic panels. The central section has a set of carbon-fibre reinforced plastic pressure vessels. Four tubes contain batteries powering the vehicle. The other three house vehicle-control systems and sensors. The rear section houses subsystems for navigation, control actuation and propulsion and scientific sensors (e.g. digital camera, upward-looking 300 kHz acoustic Doppler current profiler, 200 kHz multibeam receiver). The front section contains forward-looking collision sensor, emergency abort, the homing systems, Argos satellite data and location transmitters and flashing lights for relocation as well as science sensors (e.g. twin conductivity–temperature–depth instruments, multibeam transmitter, sub-bottom profiler, AquaLab water sampler). Payload restrictions mean that a subset of scientific instruments is actually in place on any given dive. The scientific instruments carried on Autosub are described and examples of observational data collected from each sensor in Arctic or Antarctic waters are given (e.g. of roughness at the underside of floating ice shelves and sea ice).
For the NASA Crustal Dynamics Project VLBI network, signals from quasars are recorded simultaneously at widely separated antennas. It is well known that hydrogen maser frequency standards provide the stable frequency reference used to precisely measure the difference in arrival time of the radio signals at the different antennas, enabling the determination of precise distances between the antennas. This paper reviews the practical requirements for maser support of VLBI for the Crustal Dynamics Project and describes the means used to meet these requirements for a network of eight fixed and three mobile stations which participate in approximately 200 VLBI experiments per year at locations in North America and the Pacific.
Latin America Treatment and Innovation Network in Mental Health (LATIN-MH) is a research hub located in Brazil and Peru that conducts a research project to help reduce the treatment gap in mental health in Latin America (LA). Besides its research core, LATIN-MH has a Capacity Building (CB) component that aims to help young researchers receive the specific training to contribute to the growing scientific production in mental health in LA.
LATIN-MH proposal in CB includes a series of actions to prepare professionals in the research area. The main proposals are described here, which include online study groups, promotion of scientific meetings, hands-on training in different levels and sharing of information.
LATIN-MH CB activities are at its initial stages but the proposed activities were well evaluated by the participants. The first participating fellows who finished their fellowships are contributing elsewhere in the mental treatment and human resources formation area.
The repercussion of LATIN-MH actions in CB and its evaluation, particularly on the formation of human resources and dissemination of information, show that the hub is contributing to the critic formation of young researchers and the circulation of important information.
Lower and middle income countries (LMICs) are home to >80% of the global population, but mental health researchers and LMIC investigator led publications are concentrated in 10% of LMICs. Increasing research and research outputs, such as in the form of peer reviewed publications, require increased capacity building (CB) opportunities in LMICs. The National Institute of Mental Health (NIMH) initiative, Collaborative Hubs for International Research on Mental Health reaches across five regional ‘hubs’ established in LMICs, to provide training and support for emerging researchers through hub-specific CB activities. This paper describes the range of CB activities, the process of monitoring, and the early outcomes of CB activities conducted by the five research hubs.
The indicators used to describe the nature, the monitoring, and the early outcomes of CB activities were developed collectively by the members of an inter-hub CB workgroup representing all five hubs. These indicators included but were not limited to courses, publications, and grants.
Results for all indicators demonstrate a wide range of feasible CB activities. The five hubs were successful in providing at least one and the majority several courses; 13 CB recipient-led articles were accepted for publication; and nine grant applications were successful.
The hubs were successful in providing CB recipients with a wide range of CB activities. The challenge remains to ensure ongoing CB of mental health researchers in LMICs, and in particular, to sustain the CB efforts of the five hubs after the termination of NIMH funding.
This paper briefly describes the principle of operation and science goals of the AMANDA high energy neutrino telescope located at the South Pole, Antarctica. Results from an earlier phase of the telescope, called AMANDA-BIO, demonstrate both reliable operation and the broad astrophysical reach of this device, which includes searches for a variety of sources of ultrahigh energy neutrinos: generic point sources, Gamma-Ray Bursts and diffuse sources. The predicted sensitivity and angular resolution of the telescope were confirmed by studies of atmospheric muon and neutrino backgrounds. We also report on the status of the analysis from AMANDA-II, a larger version with far greater capabilities. At this stage of analysis, details of the ice properties and other systematic uncertainties of the AMANDA-II telescope are under study, but we have made progress toward critical science objectives. In particular, we present the first preliminary flux limits from AMANDA-II on the search for continuous emission from astrophysical point sources, and report on the search for correlated neutrino emission from Gamma Ray Bursts detected by BATSE before decommissioning in May 2000. During the next two years, we expect to exploit the full potential of AMANDA-II with the installation of a new data acquisition system that records full waveforms from the in-ice optical sensors.
Compact groups are intermediate between single and binary galaxy systems, and clusters of galaxies. Because of their small numbers of members, and the small separations between the members of each group, they are good candidates for the study of galaxy interactions and mergers. In particular, high resolution imaging of these systems in neutral hydrogen can yield important data on interactions between galaxies.
The radio telescopes of the Australian National Telescope Facility (ATNF) are especially well suited to the study of neutral hydrogen gas in these systems. The Parkes 64-m telescope has a 15 arcminute FWHM beam at 21 centimeters wavelength which is sufficient to include the sky area of a typical compact group. Parkes was used for detection of HI in nine southern groups and for determination of their approximate velocities, if not previously known. Follow-up observations with the ATNF Compact Array synthesis telescope provided high resolution (20 arcsecond) images with appropriate frequency resolution to determine velocity fields for the gas distribution.
Four southern compact groups, the Hickson Compact Groups HCG 22 and HCG 26 (Hickson 1982), and the groups AM 1238–396 and ESO 410-G(024—026) have been imaged in HI, along with 12cm continuum using the Australia Telescope Compact Array (ATCA). The initial findings for the latter two groups are presented here. While ESO 410-G is not in fact a physical group, due to the discordant redshifts amongst the members, it is however presented here.
Overall for all the groups we find no other sources of HI in the field that might indicate that these are part of a larger loose group structure. This is not always the case, as with HCG 23 (Williams 1995) and HCG 95 (Hutchmeier 1999), both of whom find additional Hɪ sources within the primary beam accordant with the compact group’s velocity.
The HI is also clearly associated with each of the individual member galaxies in all cases, except for HCG 26, which envelopes the whole group as was also shown by Williams and van Gorkom (Williams 1995).
The Darwin region in northern Australia has experienced rapid population growth in recent years, and with it, an increased incidence of melioidosis. Previous studies in Darwin have associated the environmental presence of Burkholderia pseudomallei, the causative agent of melioidosis, with anthropogenic land usage and proximity to animals. In our study, we estimated the occurrence of B. pseudomallei and Burkholderia spp. relatives in faecal matter of wildlife, livestock and domestic animals in the Darwin region. A total of 357 faecal samples were collected and bacteria isolated through culture and direct DNA extraction after enrichment in selective media. Identification of B. pseudomallei, B. ubonensis, and other Burkholderia spp. was carried out using TTS1, Bu550, and recA BUR3–BUR4 quantitative PCR assays, respectively. B. pseudomallei was detected in seven faecal samples from wallabies and a chicken. B. cepacia complex spp. and Pandoraea spp. were cultured from wallaby faecal samples, and B. cenocepacia and B. cepacia were also isolated from livestock animals. Various bacteria isolated in this study represent opportunistic human pathogens, raising the possibility that faecal shedding contributes to the expanding geographical distribution of not just B. pseudomallei but other Burkholderiaceae that can cause human disease.
The region surrounding the galactic centre has been surveyed with the 210-foot telescope of the Australian National Radio Astronomy Observatory at a wavelength of 10·0 cm. At this wavelength the telescope beamwidth is 6.7 between half-intensity points.
Suicide is a devastating public health problem and very few biological treatments have been found to be effective for quickly reducing the intensity of suicidal ideation (SI). We have previously shown that a single dose of ketamine, a glutamate N-methyl-d-aspartate (NMDA) receptor antagonist, is associated with a rapid reduction in depressive symptom severity and SI in patients with treatment-resistant depression.
We conducted a randomized, controlled trial of ketamine in patients with mood and anxiety spectrum disorders who presented with clinically significant SI (n = 24). Patients received a single infusion of ketamine or midazolam (as an active placebo) in addition to standard of care. SI measured using the Beck Scale for Suicidal Ideation (BSI) 24 h post-treatment represented the primary outcome. Secondary outcomes included the Montgomery–Asberg Depression Rating Scale – Suicidal Ideation (MADRS-SI) score at 24 h and additional measures beyond the 24-h time-point.
The intervention was well tolerated and no dropouts occurred during the primary 7-day assessment period. BSI score was not different between the treatment groups at 24 h (p = 0.32); however, a significant difference emerged at 48 h (p = 0.047). MADRS-SI score was lower in the ketamine group compared to midazolam group at 24 h (p = 0.05). The treatment effect was no longer significant at the end of the 7-day assessment period.
The current findings provide initial support for the safety and tolerability of ketamine as an intervention for SI in patients who are at elevated risk for suicidal behavior. Larger, well-powered studies are warranted.
High-redshift quasars are unique probes of the evolution of supermassive black holes and the intergalactic medium at the end of the epoch of reionization. We present the optical spectra of eight new z ~ 6 quasars selected from the Panoramic Survey Telescope & Rapid Response System 1 (Pan-STARRS1). Details of the selection strategy can be found in Bañados et al. (2014). With this work we increase the number of known quasars at z < 5.7 by more than 10%. The quasars discovered here span a large range of luminosities (19.6 ≤ zP1 ≤ 21.2) and are remarkably heterogeneous in their spectral features: half of them show bright emission lines whereas the other half show weak or no Lyα emission line. We find a larger fraction of weak–line emission quasars than in lower redshift studies, although still based on low number statistics, this may imply that the quasar population could be more diverse than previously thought.
Childhood obesity is a growing problem worldwide. In recent years, out-of-home (OH) eating has been highlighted as one of the many factors contributing to the obesogenic environment. This review seeks to identify a range of existing guidelines for the provision of healthy food options for families who eat OH frequently. Nationally available nutrition policies were identified using targeted and untargeted searches of the internet to identify established strategies for providing food for children in the family eating out sector in America (US), Australia, Canada and the WHO's European Region (EUR). These were categorised on the basis of eleven pre-defined criteria including: family eating out sector included as stakeholder; inclusion of children's food OH; cost strategies for healthier food choices; provision of nutrition information for customers; nutrition training of catering staff; and monitoring and evaluation structures. Fifty-five policies were reviewed, of which 71% addressed children's food served OH, but principally only for food available in schools. Two voluntary programmes, from Colorado and Slovenia, were identified as possible best practice models as they met a majority of the evaluation criteria. The most frequently used strategy by policies to promote healthier eating OH was the provision of nutrition information on menus, while monitoring and evaluation plans were poorly incorporated into any OH strategies, thus raising issues about their effectiveness. This review has identified a range of initiatives that could be employed to make healthier eating OH more accessible for families. However, to establish best practice guidelines for healthier OH food choices further investigations are required.