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Stratigraphic records extending to Marine Oxygen Isotope Stage (MIS) 3 (57,000–29,000 cal yr BP) or older in Beringia are extremely rare. Three stratigraphic sections in interior western Alaska show near continuous sedimentological and environmental progressions extending from at least MIS 3, if not older, through MIS 1 (14,000 cal yr BP–present). The Kolmakof, Sue Creek, and VABM (vertical angle bench mark) Kuskokwim sections along the central Kuskokwim River, once a highland landscape at the fringe of central and eastern Beringia, contain aeolian deposition and soil sequences dating beyond 50,000 14C yr BP. Thick peaty soil, shallow lacustrine, and tephra deposits represent the MIS 3 interstade (or older). Sand sheet and loess deposits, wedge cast development, and very thin soil development mark the later MIS 3 period and the transition into the MIS 2 stade (29,000–14,000 cal yr BP). Loess accumulation with thicker soil development occurred between ~16,000–13,500 cal yr BP at the MIS 2 and MIS 1 transition. After ~13,500 cal yr BP, loess accumulation waned and peat development increased throughout MIS 1. These stratigraphic sequences represent transitions between a warm and moist period during MIS 3, to a cooler and more arid period during MIS 2, then a return to warmer and moister climates in MIS 1.
North American studies show bipolar disorder is associated with elevated
rates of problem gambling; however, little is known about rates in the
different presentations of bipolar illness.
To determine the prevalence and distribution of problem gambling in
people with bipolar disorder in the UK.
The Problem Gambling Severity Index was used to measure gambling problems
in 635 participants with bipolar disorder.
Moderate to severe gambling problems were four times higher in people
with bipolar disorder than in the general population, and were associated
with type 2 disorder (OR = 1.74, P = 0.036), history of
suicidal ideation or attempt (OR = 3.44, P = 0.02) and
rapid cycling (OR = 2.63, P = 0.008).
Approximately 1 in 10 patients with bipolar disorder may be at moderate
to severe risk of problem gambling, possibly associated with suicidal
behaviour and a rapid cycling course. Elevated rates of gambling problems
in type 2 disorder highlight the probable significance of modest but
unstable mood disturbance in the development and maintenance of such
Recent studies suggest that sand can serve as a vehicle for exposure of humans to pathogens at beach sites, resulting in increased health risks. Sampling for microorganisms in sand should therefore be considered for inclusion in regulatory programmes aimed at protecting recreational beach users from infectious disease. Here, we review the literature on pathogen levels in beach sand, and their potential for affecting human health. In an effort to provide specific recommendations for sand sampling programmes, we outline published guidelines for beach monitoring programmes, which are currently focused exclusively on measuring microbial levels in water. We also provide background on spatial distribution and temporal characteristics of microbes in sand, as these factors influence sampling programmes. First steps toward establishing a sand sampling programme include identifying appropriate beach sites and use of initial sanitary assessments to refine site selection. A tiered approach is recommended for monitoring. This approach would include the analysis of samples from many sites for faecal indicator organisms and other conventional analytes, while testing for specific pathogens and unconventional indicators is reserved for high-risk sites. Given the diversity of microbes found in sand, studies are urgently needed to identify the most significant aetiological agent of disease and to relate microbial measurements in sand to human health risk.
Two broad aims drive weed science research: improved management and improved
understanding of weed biology and ecology. In recent years, agricultural
weed research addressing these two aims has effectively split into separate
subdisciplines despite repeated calls for greater integration. Although some
excellent work is being done, agricultural weed research has developed a
very high level of repetitiveness, a preponderance of purely descriptive
studies, and has failed to clearly articulate novel hypotheses linked to
established bodies of ecological and evolutionary theory. In contrast,
invasive plant research attracts a diverse cadre of nonweed scientists using
invasions to explore broader and more integrated biological questions
grounded in theory. We propose that although studies focused on weed
management remain vitally important, agricultural weed research would
benefit from deeper theoretical justification, a broader vision, and
increased collaboration across diverse disciplines. To initiate change in
this direction, we call for more emphasis on interdisciplinary training for
weed scientists, and for focused workshops and working groups to develop
specific areas of research and promote interactions among weed scientists
and with the wider scientific community.
We present the results of an approximately 6 100 deg2 104–196 MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December: the MWACS. The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The survey covers approximately 20.5 h < RA < 8.5 h, − 58° < Dec < −14°over three frequency bands centred on 119, 150 and 180 MHz, with image resolutions of 6–3 arcmin. The catalogue has 3 arcmin angular resolution and a typical noise level of 40 mJy beam− 1, with reduced sensitivity near the field boundaries and bright sources. We describe the data reduction strategy, based upon mosaicked snapshots, flux density calibration, and source-finding method. We present a catalogue of flux density and spectral index measurements for 14 110 sources, extracted from the mosaic, 1 247 of which are sub-components of complexes of sources.
Background: Ependymomas are rare tumors of the central nervous system whose management is controversial. This population-based study of adults and children with ependymoma aims to (1) identify clinical and treatment-related factors that impact survival and (2) determine if postoperative radiotherapy (RT) can improve survival of patients with subtotal resection (STR) to levels similar to patients who had gross total resection (GTR). Methods: This retrospective population-based study evaluated 158 patients with ependymoma diagnosed between 1975-2007 in Alberta, Canada. Results: Younger patients (<7 years of age) were more likely to be diagnosed with grade III tumors compared with adults in whom grade I tumors were more common (p=0.003). Adults were more likely to have spinally located tumors compared to young children whose tumors were typically found in the brain. Overall, young children with ependymoma were more likely to die than older children or adults (p=0.001). An equivalent number of patients underwent GTR as compared with STR (48% vs 45%, respectively). Overall, older age, spinal tumor location, lower grade, and GTR were associated with improved progression free survival but only GTR was associated with significant improvement in overall survival. Median survival after STR and RT was 82 months compared with 122 months in patients who had GTR (p=0.0022). Conclusions: This is the first Canadian population-based analysis of patients with ependymoma including adults and children. Extent of resection appears to be the most important factor determining overall survival. Importantly, the addition of RT to patients initially treated with STR does not improve survival to levels similar to patients receiving GTR.
Significant new opportunities for astrophysics and cosmology have been identified at low radio frequencies. The Murchison Widefield Array is the first telescope in the southern hemisphere designed specifically to explore the low-frequency astronomical sky between 80 and 300 MHz with arcminute angular resolution and high survey efficiency. The telescope will enable new advances along four key science themes, including searching for redshifted 21-cm emission from the EoR in the early Universe; Galactic and extragalactic all-sky southern hemisphere surveys; time-domain astrophysics; and solar, heliospheric, and ionospheric science and space weather. The Murchison Widefield Array is located in Western Australia at the site of the planned Square Kilometre Array (SKA) low-band telescope and is the only low-frequency SKA precursor facility. In this paper, we review the performance properties of the Murchison Widefield Array and describe its primary scientific objectives.
Intracranial complications are recognised as rare, but serious, sequelae of endoscopic sinus surgery.
A 56-year-old woman was referred after developing meningitis following elective functional endoscopic sinus surgery. Computed tomography demonstrated a significant defect of the skull base in the right posterior ethmoid, clearly visible on both coronal and sagittal sections. Operative exploration demonstrated the skull base to be intact in the posterior ethmoid area identified on the scan, and the overlying mucosa appeared undisturbed. Scans were reviewed in the light of operative findings; coronal and sagittal images were found to be reconstructions. Directly acquired coronal computed tomography, undertaken three weeks after surgery, demonstrated a complete bony plate in the right posterior ethmoid at the site previously identified as dehiscent.
Discussion and conclusion:
We speculate that the posterior ethmoid defect was actually an artefact of reconstruction. We cannot exclude the alternative possibility of remineralisation, but given the time frame this seems unlikely. This case highlights the need for caution when interpreting reconstructed images of the thin bony plates of the skull base and lamina papyracea, as regards both clinical significance and medicolegal reporting. While virtual defects have been reported in the superior semicircular canals as a result of reconstructed images, we believe this to be the first reported case demonstrating a similar problem in the anterior skull base.
Sensor networks have recently generated a great deal of research interest within the computer and physical sciences, and their use for the scientific monitoring of remote and hostile environments is increasingly commonplace. While early sensor networks were a simple evolution of existing automated data loggers, that collected data for later offline scientific analysis, more recent sensor networks typically make current data available through the Internet, and thus, are increasingly being used for the real-time monitoring of environmental events such as floods or storm events (see  for a review of such environmental sensor networks).
Using real-time sensor data in this manner presents many novel challenges. However, more significantly for us, many of the information processing tasks that would previously have been performed offline by the owner or single user of an environmental sensor network (such as detecting faulty sensors, fusing noisy measurements from several sensors, and deciding how frequently readings should be taken), must now be performed in real-time on the mobile computers and PDAs carried by the multiple different users of the system (who may have different goals and may be using sensor readings for very different tasks). Importantly, it may also be necessary to use the trends and correlations observed in previous data to predict the value of environmental parameters into the future, or to predict the reading of a sensor that is temporarily unavailable (e.g. due to network outages).