2,194 research outputs found
Library
This history for the Library was collected to commemorate DMACC\u27s 50th anniversary celebration during the 2015-16 academic year
Advanced Scanning Probe Microscopy for Materials Research
Scanning probe microscopy (SPM) encompasses a set of advanced techniques for mapping the structure and properties of the surfaces of materials from the atomic to micro scales. The most widely used SPM technique is atomic force microscopy (AFM), in which forces exerted between the tip of a needle probe and the sample surface can be measured with extremely high precision. By recording these forces as the tip rasters across the surface, an image of the sample surface topography is obtained. Beyond the surface topography, several SPM techniques can provide quantitative information about the properties of a material’s surface. These include scanning Kelvin probe force microscopy (KPFM) for surface potential measurements, scanning capacitance microscopy (SCM) for surface capacitance mapping, conductive and tunneling AFM (C-AFM and TUNA) for imaging the electrical conductance of a surface, as well as several techniques for imaging the mechanical properties of a surface. These advanced SPM techniques provide tools for direct structure-property correlations in materials at the nanoscale and are powerful capabilities for materials research, especially when co-located with other surface analytical techniques. Each of these advanced SPM techniques is available for materials research in the Boise State University Surface Science Laboratory
TiO2 Coatings Formed by Atomic Layer Deposition for Enhanced Corrosion Performance of Mg-biomaterials
Magnesium (Mg) alloys have experienced increased attention in the area of biomaterials due to Mg being considered a resorbable biomaterial. Mg alloy implants can potentially be designed to degrade in the body, thus an implant would not remain in the body for longer than is needed to perform its task. Mg and many of its alloys are considered to be biocompatible and non-toxic in the body; however, due to the high rate at which Mg degrades a negative host response is expected. A novel approach to inhibit corrosion rate using thin film coatings on a Mg alloy (AZ31B) via atomic layer deposition (ALD) is proposed. ALD is based on saturated surface reactions on the substrate unlike other thin film deposition techniques such as chemical vapor deposition (CVD) and physical vapor deposition (PVD). Sequentially-performed surface reactions between the substrate and precursor molecules water and titanium tetrachloride (H2O , TiCl4) result in thin film growth of amorphous titanium dioxide (TiO2). TiO2 is grown in an atomic layer-by-layer fashion during ALD allowing sub-nanometer thickness control of growth, with excellent coating uniformity and step coverage. TiO2 coatings and their impact on the corrosion resistance of AZ31B were characterized using atomic force microscopy, scanning electron microscopy, electrochemical impedance spectroscopy, and linear polarization measurements
White-light flares on cool stars in the Kepler Quarter 1 Data
We present the results of a search for white light flares on the ~23,000 cool
dwarfs in the Kepler Quarter 1 long cadence data. We have identified 373
flaring stars, some of which flare multiple times during the observation
period. We calculate relative flare energies, flare rates and durations, and
compare these with the quiescent photometric variability of our sample. We find
that M dwarfs tend to flare more frequently but for shorter durations than K
dwarfs, and that they emit more energy relative to their quiescent luminosity
in a given flare than K dwarfs. Stars that are more photometrically variable in
quiescence tend to emit relatively more energy during flares, but variability
is only weakly correlated with flare frequency. We estimate distances for our
sample of flare stars and find that the flaring fraction agrees well with other
observations of flare statistics for stars within 300 pc above the Galactic
Plane. These observations provide a more rounded view of stellar flares by
sampling stars that have not been pre-selected by their activity, and are
informative for understanding the influence of these flares on planetary
habitability.Comment: 42 pages, 10 figures, 2 tables; Accepted for publication in the
Astronomical Journa
Progress on the Structural and Mechanical Design of the Giant Magellan Telescope
ABSTRACT The Giant Magellan Telescope (GMT), one of several next generation Extremely Large Telescopes (ELTs), is a 25.4 meter diameter altitude over azimuth design set to be built at the summit of Cerro Campanas at the Las Campanas Observatory in Chile. The primary mirror consists of 7 individual 8.4 meter diameter segments resulting in an equivalent collecting area of a 21.5 meter diameter single mirror. The telescope structure, optics and instrumentation has a rotating mass of approximately 1250 metric tons and stands approximately 40 meters tall. This paper reports the results of our ongoing preliminary design and development of the GMT structure and its major mechanical and opto-mechanical components. A major recent redesign of the Gregorian Instrument Rotator (GIR) resulted in significant changes to the telescope structure and several mechanisms. Design trade studies of various aspects of the main structure, hydrostatic bearing system, main axes drives, M2 positioner, M3 subsystem and the corrector-ADC subsystem have refined the preliminary design in these areas
The End of Zero-Hit Queries: Query Previews for NASA's Global Change Master Directory
The Human-Computer Interaction Laboratory (HCIL) of the University of
Maryland and NASA have collaborated over the last three years to refine
and apply user interface research concepts developed at HCIL in order to
improve the usability of NASA data services. The research focused on
dynamic query user interfaces, visualization, and overview +preview
designs. An operational prototype, using query previews, was implemented
with NASA's Global Change Master Directory (GCMD), a directory service for
earth science data sets. Users can see the histogram of the data
distribution over several attributes and choose among attribute values. A
result bar shows the cardinality of the result set, thereby preventing
users from submitting queries that would have zero hits. Our experience
confirmed the importance of metadata accuracy and completeness. The query
preview interfaces make visible problems or holes in the metadata that are
unnoticeable with classic form fill-in interfaces. This could be seen as a
problem, but we think that it will have a long-term beneficial effect on
the quality of the metadata as data providers will be compelled to produce
more complete and accurate metadata. The adaptation of the research
prototype to the NASA data required revised data structures and
algorithms.
(Also cross-referenced as UMIACS-TR-97-84
Successful treatment of HIV-associated multicentric Castleman's disease and multiple organ failure with rituximab and supportive care: a case report
<p>Abstract</p> <p>Introduction</p> <p>Multicentric Castleman's Disease (MCD), a lymphoproliferative disorder associated with Human Herpes Virus-8 (HHV-8) infection, is increasing in incidence amongst HIV patients. This condition is associated with lymphadenopathy, polyclonal gammopathy, hepato-splenomegaly and systemic symptoms. A number of small studies have demonstrated the efficacy of the anti-CD20 monoclonal antibody, rituximab, in treating this condition.</p> <p>Case presentation</p> <p>We report the case of a 46 year old Zambian woman who presented with pyrexia, diarrhoea and vomiting, confusion, lymphadenopathy, and renal failure. She rapidly developed multiple organ failure following the initiation of treatment of MCD with rituximab. Following admission to intensive care (ICU), she received prompt multi-organ support. After 21 days on the ICU she returned to the haematology medical ward, and was discharged in remission from her disease after 149 days in hospital.</p> <p>Conclusion</p> <p>Rituximab, the efficacy of which has thus far been examined predominantly in patients <it>outside </it>the ICU, in conjunction with extensive organ support was effective treatment for MCD with associated multiple organ failure. There is, to our knowledge, only one other published report of its successful use in an ICU setting, where it was combined with cyclophosphamide, adriamycin and prednisolone. Reports such as ours support the notion that critically unwell patients with HIV and haematological disease <it>can </it>benefit from intensive care.</p
Nonlinear landscape and cultural response to sea-level rise
Dataset S1 (separate file). Relative sea-level database for Scilly comprising directly dated radiocarbon and optically stimulated luminescence samples with corresponding metainformation (lithostratigraphy, elevation, depositional environment and indicative meaning interpretations, paleotidal range change and sea-level calculations) following the ‘HOLSEA’ (‘Geographic Variability of Holocene Relative Sea Level’) protocol (Khan et al., 2019*). Dataset S2 (separate file). Table containing pollen results as relative abundance (genus level), modelled ages and age uncertainty for pollen samples, landcover index results (community cluster numbers and nMDS ordination axes 1 and 2), foraminifera results as species counts and transfer function results as paleomarsh elevations with uncertainty (1σ). Foraminifera samples with low test concentrations have indicative ranges (from mean high water neap tides to highest astronomical tides) in place of paleomarsh elevation estimations. Foraminifera abbreviations: H.wil – Haplophragmoides wilbertii ; J.mac – Jadammina macrescens ; M.fus – Miliammina fusca ; P.ipo – Polysaccammina ipohalina ; T.inf – Trochammina infalta ; T.och – Trochammina ochracea ; A.bat - Ammonia batavus ; A.mam – Asterigerinata mamilla ; B.var – Bolivina variablis; E.cri – Elphidium crispum ; E.wil – Elphidium Williamsoni ; F.spp. – Fissurina spp. ; Elphidium spp. ; H.ger – Haynesina germanica ; L.lob – Lobatula lobatula ; O.spp. – Oolha spp. ; Q.sem – Quinqueloculina seminula; R.spp. – Rosalina spp.. Dataset S3 (separate file). Database containing three worksheets for developing archaeological indices for Scilly. ‘SWBritain’ – Radiocarbon dates from Devon and Cornwall used to develop a summed probability distribution curve as an estimate of population demographic variation in Southwest Britain. ‘NWFrance’ - Radiocarbon dates from Brittany and Normandy used to develop a summed probability distribution curve as an estimate of population demography in Northwest France. ‘Scilly’ – Archaeological monuments from Scilly used to develop a probabilistic index of population variability.The article associated with these datasets is located in ORE at: http://hdl.handle.net/10871/123489Rising sea levels have been associated with human migration and behavioral shifts throughout prehistory, often with an emphasis on landscape submergence and consequent societal collapse. However, the assumption that future sea-level rise will drive similar adaptive responses is overly simplistic. Whilst the change from land to sea represents a dramatic and permanent shift for pre-existing human populations, the process of change is driven by a complex set of physical and cultural processes with long transitional phases of landscape and socio-economic change. Here we use reconstructions of prehistoric sea-level rise, paleogeographies, terrestrial landscape change and human population dynamics to show how the gradual inundation of an island archipelago resulted in decidedly non-linear landscape and cultural responses to rising sea-levels. Interpretation of past and future responses to sea-level change requires a better understanding of local physical and societal contexts to assess plausible human response patterns in the future.Historic EnglandWelsh GovernmentHigher Education Funding Council for Wale
Catching Element Formation In The Act
Gamma-ray astronomy explores the most energetic photons in nature to address
some of the most pressing puzzles in contemporary astrophysics. It encompasses
a wide range of objects and phenomena: stars, supernovae, novae, neutron stars,
stellar-mass black holes, nucleosynthesis, the interstellar medium, cosmic rays
and relativistic-particle acceleration, and the evolution of galaxies. MeV
gamma-rays provide a unique probe of nuclear processes in astronomy, directly
measuring radioactive decay, nuclear de-excitation, and positron annihilation.
The substantial information carried by gamma-ray photons allows us to see
deeper into these objects, the bulk of the power is often emitted at gamma-ray
energies, and radioactivity provides a natural physical clock that adds unique
information. New science will be driven by time-domain population studies at
gamma-ray energies. This science is enabled by next-generation gamma-ray
instruments with one to two orders of magnitude better sensitivity, larger sky
coverage, and faster cadence than all previous gamma-ray instruments. This
transformative capability permits: (a) the accurate identification of the
gamma-ray emitting objects and correlations with observations taken at other
wavelengths and with other messengers; (b) construction of new gamma-ray maps
of the Milky Way and other nearby galaxies where extended regions are
distinguished from point sources; and (c) considerable serendipitous science of
scarce events -- nearby neutron star mergers, for example. Advances in
technology push the performance of new gamma-ray instruments to address a wide
set of astrophysical questions.Comment: 14 pages including 3 figure
Crop Updates 2006 - Katanning
This session covers sixteen papers from different authors
2006 SEASONAL OUTLOOK, David Stephens and Michael Meuleners, Department of Agriculture
Review of climate model summaries reported in the Department of Agriculture’s growing season outlooks, Meredith Fairbanks, Department of Agriculture
Farmers commodity outlook 2006, Thomas Schulz, Department of Agriculture
Why is salinity such a difficult problem for plant breeders? T J Flowers, TD Colmer, University of Western Australia
Matching nitrogen supply to wheat demand in 2005, Narelle Simpson, Ron McTaggart, Wal Anderson, Lionel Martin and Dave Allen, Department of Agriculture
Wheat varieties in 2006, Brenda Shackley, Department of Agriculture
Performance of dwarf potential milling oat varieties in Western Australian environments, Raj Malik and Kellie Winfield, Department of Agriculture
Field pea lessons for 2006, Rodger Beermir, Department of Agriculture
Better returns from Durum wheat, Shahahan Miyan, Department of Agriculture
Summer weeds can reduce grain yield and protein, Dr. Abul Hashem, Department of Agriculture, Dr Shahab Pathan, Department of Agriculture, Vikki Osten, Queensland Department of Primary Industries and Fisheries
Management of Summer Weeds, Alex Douglas, Department of Agriculture
Frost or Friction, Garren Knell, Steve Curtin, Wade Longmuir, Consult Ag Pty Ltd
PROFITING FROM MARGINAL LAND SEMINAR
Producing Bio-Diesel and rubber from marginal land?? Dr Henry Brockman, Department of Agriculture
SGSL Producer network – on ground implementation of saltbush based pastures, Justin Hardy, Arjen Ryder, John Paul Collins and Jessica Johns, Department of Agriculture
Enhancing the profitability of “Edenia” using saltbush and perenials, SGSL Producer case study, John Pepall, Jinka’s Hill LCDC
Investment in saltland pastures, Allan Herbert, Department of Agricultur
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