5,939 research outputs found
Seasonal Patterns of Nitrogen Fixation in Termites
Summary
1. Termite nitrogenase activity was highest in autumn and spring (≈ 3 µg N2 fixed termite fresh mass (g)–1 day–1) and lowest in winter and summer (≈ 0·8 µg N2 fixed termite fresh mass (g)–1 day–1).
2. The nitrogenase activity of worker termites was significantly higher than all other castes (1·58 ± 0·27 µg N2 fixed termite fresh mass (g)–1 day–1).
3. Worker termites constituted the largest proportion of all the castes throughout the study period (≈ 90%).
4. The localized input of fixed nitrogen by termites may reach 15·3 mg N log–1 day–1 and 5·6 g N log–1 year–1
Problems With the Interpretation of Mark-Release-Recapture Data in Subterranean Termites (Isoptera: Rhinotermitidae)
The Lincoln index (Peterson method) is frequently used to estimate animal population size in mark-release-recapture studies. We tested the accuracy of this method to estimate termite colony size using logs infested with termites that were maintained in the laboratory. Termites were fed paper towels dyed either with 0.05% or 0.1% (w/w) of the dye marker Nile blue and released into their host logs in the laboratory. Following recapture a week later, estimates of termite population size for termites dyed with 0.05% Nile blue, and were approximately 3 times greater for termites dyed with 0.1% Nile blue. Concentrations of 0.1% Nile blue are not used in field studies because they result in higher mortality than 0.05% in laboratory trials. However, our data suggest that greater accuracy may be obtained using the higher dye concentration. The triple-catch method is frequently used in place of the Lincoln index in order to reduce standard errors of the estimate. However, our standard errors were lower than those of many published studies using the triple-catch method. The assumptions governing the efficacy of mark-release-recapture may be violated because of the potential model biases that result from developing marking techniques in the laboratory that are intended for field use
Alignment and Aperture Scan at the Fermilab Booster
The Fermilab booster has an intensity upgrade plan called the Proton
Improvement plan (PIP). The flux throughput goal is 2E17 protons/hour, which is
almost double the current operation at 1.1E17 protons/hour. The beam loss in
the machine is going to be the source of issues. The booster accelerates beam
from 400 MeV to 8 GeV and extracts to the Main Injector. Several percent of the
beam is lost within 3 msec after the injection. The aperture at injection
energy was measured and compared with the survey data. The magnets are going to
be realigned in March 2012 in order to increase the aperture. The beam studies,
analysis of the scan and alignment data, and the result of the magnet moves
will be discussed in this paper.Comment: 3 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012, New Orleans, Louisian
Physical, psychosocial, relationship, and economic burden of caring for people with cancer: A review
The aim of this article is to provide an overview of the issues faced by caregivers of people diagnosed with cancer, with a particular emphasis on the physical, psychosocial, and economic impact of caring. A review of the literature identified cancer as one of the most common health conditions in receipt of informal caregiving, with the majority of caregivers reporting taking on the role of caring because of family responsibility and there being little choice or no one else to provide the care. For some, caregiving can extend for several years and become equivalent to a full-time job, with significant consequent health, psychosocial, and financial burdens. Having a better understanding of the critical and broad roles that caregivers play in the oncology setting and the impact of these on their health and well-being may assist health care professionals in supporting caregivers with these tasks and targeting services and interventions toward those most in need. Copyright © 2012 by American Society of Clinical Oncology
Training AAC users in user-centred design
User-centred design (UCD) with a focus on usability provides product developers with a design approach in which users are involved in every stage of the process: when gathering requirements; when evaluating alternative designs; and when evaluating interactive prototypes.The characteristics of people who use augmentative and alternative communication (AAC) make it difficult to follow a truly UCD approach, which in part may contribute to the high rejection of AAC devices. Training workshops have been delivered to introduce users and AAC professionals to the UCD process.Initial feedback indicates that they feel more empowered to evaluate systems and to engage in the design of new systems after attending the workshop
Performance of AAOmega: the AAT multi-purpose fibre-fed spectrograph
AAOmega is the new spectrograph for the 2dF fibre-positioning system on the
Anglo-Australian Telescope. It is a bench-mounted, double-beamed design, using
volume phase holographic (VPH) gratings and articulating cameras. It is fed by
392 fibres from either of the two 2dF field plates, or by the 512 fibre SPIRAL
integral field unit (IFU) at Cassegrain focus. Wavelength coverage is 370 to
950nm and spectral resolution 1,000-8,000 in multi-Object mode, or 1,500-10,000
in IFU mode. Multi-object mode was commissioned in January 2006 and the IFU
system will be commissioned in June 2006.
The spectrograph is located off the telescope in a thermally isolated room
and the 2dF fibres have been replaced by new 38m broadband fibres. Despite the
increased fibre length, we have achieved a large increase in throughput by use
of VPH gratings, more efficient coatings and new detectors - amounting to a
factor of at least 2 in the red. The number of spectral resolution elements and
the maximum resolution are both more than doubled, and the stability is an
order of magnitude better.
The spectrograph comprises: an f/3.15 Schmidt collimator, incorporating a
dichroic beam-splitter; interchangeable VPH gratings; and articulating red and
blue f/1.3 Schmidt cameras. Pupil size is 190mm, determined by the competing
demands of cost, obstruction losses, and maximum resolution. A full suite of
VPH gratings has been provided to cover resolutions 1,000 to 7,500, and up to
10,000 at particular wavelengths.Comment: 13 pages, 4 figures; presented at SPIE, Astronomical Telescopes and
Instrumentation, 24 - 31 May 2006, Orlando, Florida US
The Role of Cognitive Factors in Predicting Balance and Fall Risk in a Neuro-Rehabilitation Setting
INTRODUCTION: There is a consistent body of evidence supporting the role of cognitive functions, particularly executive function, in the elderly and in neurological conditions which become more frequent with ageing. The aim of our study was to assess the role of different domains of cognitive functions to predict balance and fall risk in a sample of adults with various neurological conditions in a rehabilitation setting. METHODS: This was a prospective, cohort study conducted in a single centre in the UK. 114 participants consecutively admitted to a Neuro-Rehabilitation Unit were prospectively assessed for fall accidents. Baseline assessment included a measure of balance (Berg Balance Scale) and a battery of standard cognitive tests measuring executive function, speed of information processing, verbal and visual memory, visual perception and intellectual function. The outcomes of interest were the risk of becoming a faller, balance and fall rate. RESULTS: Two tests of executive function were significantly associated with fall risk, the Stroop Colour Word Test (IRR 1.01, 95% CI 1.00-1.03) and the number of errors on part B of the Trail Making Test (IRR 1.23, 95% CI 1.03-1.49). Composite scores of executive function, speed of information processing and visual memory domains resulted in 2 to 3 times increased likelihood of having better balance (OR 2.74 95% CI 1.08 to 6.94, OR 2.72 95% CI 1.16 to 6.36 and OR 2.44 95% CI 1.11 to 5.35 respectively). CONCLUSIONS: Our results show that specific subcomponents of executive functions are able to predict fall risk, while a more global cognitive dysfunction is associated with poorer balance
The Effects of Increased Provision of Thoracic Surgical Specialists on the Variation in Lung Cancer Resection Rate in England
Introduction:There is a wide variation in the lung cancer resection rate in England. We assessed the effect of the regional provision of thoracic surgery service on the variation in lung cancer resection rate.Methods:A retrospective observational study correlating National Lung Cancer Audit data with thoracic surgery workforce data was performed to review the lung cancer resection rate in England in 2008 and 2009.Results:In 2008, there was a sixfold variation in resection rate, with a higher resection rate in hospitals where surgeons were based (base hospitals) than in peripheral hospitals (20.0% versus 11.6%, p < 0.001). The resection rate was also higher in cancer networks, which were served by two or more specialist thoracic surgeons (14.6% versus 12.7%, p = 0.028), and where surgeons were present in more than two-thirds of the lung cancer multidisciplinary team meetings (14.4% versus 12.0%, p = 0.046). In 2009, the overall resection rate increased from 14.5% to 18.4%. Four units increased their number of specialist thoracic surgeons and had a significantly higher increase in resection rate than units without expansion (relative rise 66.3% versus 19.2%; p = 0.022).Conclusions:The large variation in the resection rate seems, in part, to be related to the local availability of specialist thoracic surgeons. The greatest improvement in the resection rate was in units with expansion of specialist thoracic surgeons. We suggest the expansion of specialist thoracic surgeons will improve the resection rate and thereby the overall survival of lung cancer in England. This has significant implications for the future of training in cardiothoracic surgery and organization of cancer services
Oxo-aglaiastatin-mediated inhibition of translation initiation
We thank Dr. Elias George (McGill University) for the kind gift of Pgp-1-expressing HeLa cells. RIM was supported by a doctoral fellowship from the Cole Foundation. This research was supported by a grant from the Canadian Institutes of Health Research (FDN-148366) to JP. J.A.P., Jr. is supported by NIH Grant R35 GM118173. Work at the Boston University Center for Molecular Discovery is supported by Grant R24 GM111625. (Cole Foundation; FDN-148366 - Canadian Institutes of Health Research; R35 GM118173 - NIH; R24 GM111625)Published versionSupporting documentatio
Recommended from our members
Late Wisconsin glaciation of Hadwen and Summer islands, Tuktoyaktuk Coastlands, NWT, Canada
The exact timing of the last major advance of the Laurentide Ice Sheet onto the Beaufort Sea coastlands of western Arctic Canada is unclear but significant to our understanding of landscape change and palaeo-ice stream chronology. Optical stimulated luminescence dating of preglacial and postglacial aeolian sand from Hadwen and Summer islands, in the Tuktoyaktuk Coastlands, indicates that glaciation took place between about 17.5 and 15 ka, and most likely between 16.6 and 15.9 ka, coinciding with Heinrich event 1. At this time the Mackenzie Trough palaeo-ice stream advanced into a cold-climate sandy desert, interrupting aeolian activity
- …