215 research outputs found
Clinical Skin Microbiology RazaAlyHowardMaibachCharles CThomas1978SpringfieldIllinois133$14.50, 50 illustrations
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Imaging at the National Gallery of Art, Washington D.C.
This report provides the description of a recent fine art spectral imaging session at the National Gallery of Art, Washington D. C. This report also includes subsequent evaluation of the performance of our multi-channel visible-spectral imaging (MVSI) system. The multi-band channels analyzed in this report were obtained using a monochrome CCD and a liquid-crystal tunable filter (LCTF) capturing 31 narrow-band channels. The results showed the effectiveness of our designed spectral imaging when used at a museum environment to capture spectral imaging of fine art paintings. Furthermore, we also verified the dependence of the performance on the selection of the characterization target. Various combinations of imaged targets were used to generate the transformation. Among our characterization target combinations, the one that includes GretagMacbeth ColorChecker DC combined with a target of blue pigments was selected considering its impact on spectral estimation performance in reconstructing painting pigments (Gamblin target). This result points directions to a design of a universal target for painting spectral imaging and estimation
Imposing Symmetry On A Complete Matrix Of Commuter Travel Elasticities
Travel price and time elasticities are increasingly being derived from discrete choice models of the multinomial or nested logit form. These elasticities are then applied to obtain predictions of changes in travel demand consequent on a policy change in prices and travel times. The majority of the choice elasticities are estimated within the behavioural setting of modal choice, holding total travel fixed. A few mode choice models have recently relaxed the strong assumption of constant variance in the random components of the indirect utility function to enable the derivation of behaviourally meaningful cross choice elasticities. Under constant variance, only the direct choice elasticities have behavioural meaning. While this advance in discrete choice modelling is to be applauded, the procedures used derive share elasticities conditional on a fixed total demand, and in addition make no corrections for two important conditions required to ‘convert’ the choice elasticity matrix into a demand elasticity matrix - namely symmetry and share weighted column sums. This paper takes a set of empirical choice elasticities and shows the procedures required to adjust these elasticities to arrive at a matrix of demand elasticities. We draw on a recent data set collected in Sydney which utilises revealed preference and stated choice data to estimate a joint model of ticket choice conditional on mode and choice of mode for commuter travel
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Mechanical behaviour and environmental stability of continuous fibre-reinforced glass-ceramic matrix composites
The mechanical behaviour of three continuous Silicon carbide fibre-reinforced glass-ceramic matrix composites has been investigated at room and high temperatures. Commercially available composites with magnesium aluminosilicate, calcium aluminosilicate and barium magnesium aluminosilicate glass-ceramic matrices were considered. The materials were tested in the as-received and aged (heat-treated in a n oxidizing environment) condition. Four-point bend static tests and fiexural creep, fatigue and creep-fatigue tests were carried out a s well as a small quantity of tensile tests of aged composites. The experimental results have highlighted the importance of the carbon-rich layer at the fibre/matrix interface for obtaining "graceful" failures. At temperatures of 700 to 800 °C oxidative degradation of the interface results in significant strength reduction and a transition to brittle fracture mode. By rapid heat treatment of the materials at 1100°C for 1 h it is possible to seal the fibre ends by forming a silica "plug" which prevents oxygen ingress, retaining the carbon-rich interphase and composite behaviour. The results of the creep and creep-fatigue tests indicate low-cycle loading has a strong influence on the life of components at high temperatures
Hiding in plain sight:evidence of hybridization between Cape mountain zebra (Equus zebra zebra) and plains zebra (Equus quagga burchelli)
Hiding in plain sight:evidence of hybridization between Cape mountain zebra (Equus zebra zebra) and plains zebra (Equus quagga burchelli)
Screening Colonoscopy in the US: Attitudes and Practices of Primary Care Physicians
BACKGROUND: Rising colorectal cancer (CRC) screening rates in the last decade are attributable almost entirely to increased colonoscopy use. Little is known about factors driving the increase, but primary care physicians (PCPs) play a central role in CRC screening delivery.
OBJECTIVE: Explore PCP attitudes toward screening colonoscopy and their associations with CRC screening practice patterns.
DESIGN: Cross-sectional analysis of data from a nationally representative survey conducted in 2006-2007.
PARTICIPANTS: 1,266 family physicians, general practitioners, general internists, and obstetrician-gynecologists.
MAIN MEASURES: Physician-reported changes in the volume of screening tests ordered, performed or supervised in the past 3 years, attitudes toward colonoscopy, the influence of evidence and perceived norms on their recommendations, challenges to screening, and practice characteristics.
RESULTS: The cooperation rate (excludes physicians without valid contact information) was 75%; 28% reported their volume of FOBT ordering had increased substantially or somewhat, and the majority (53%) reported their sigmoidoscopy volume decreased either substantially or somewhat. A majority (73%) reported that colonoscopy volume increased somewhat or substantially. The majority (86%) strongly agreed that colonoscopy was the best of the available CRC screening tests; 69% thought it was readily available for their patients; 59% strongly or somewhat agreed that they might be sued if they did not offer colonoscopy to their patients. All three attitudes were significantly related to substantial increases in colonoscopy ordering.
CONCLUSIONS: PCPs report greatly increased colonoscopy recommendation relative to other screening tests, and highly favorable attitudes about colonoscopy. Greater emphasis is needed on informed decision-making with patients about preferences for test options
Use of PRECIS ratings in the National Institutes of Health (NIH) Health Care Systems Research Collaboratory
The health disparities cancer collaborative: a case study of practice registry measurement in a quality improvement collaborative
<p>Abstract</p> <p>Background</p> <p>Practice registry measurement provides a foundation for quality improvement, but experiences in practice are not widely reported. One setting where practice registry measurement has been implemented is the Health Resources and Services Administration's Health Disparities Cancer Collaborative (HDCC).</p> <p>Methods</p> <p>Using practice registry data from 16 community health centers participating in the HDCC, we determined the completeness of data for screening, follow-up, and treatment measures. We determined the size of the change in cancer care processes that an aggregation of practices has adequate power to detect. We modeled different ways of presenting before/after changes in cancer screening, including count and proportion data at both the individual health center and aggregate collaborative level.</p> <p>Results</p> <p>All participating health centers reported data for cancer screening, but less than a third reported data regarding timely follow-up. For individual cancers, the aggregate HDCC had adequate power to detect a 2 to 3% change in cancer screening, but only had the power to detect a change of 40% or more in the initiation of treatment. Almost every health center (98%) improved cancer screening based upon count data, while fewer (77%) improved cancer screening based upon proportion data. The aggregate collaborative appeared to increase breast, cervical, and colorectal cancer screening rates by 12%, 15%, and 4%, respectively (p < 0.001 for all before/after comparisons). In subgroup analyses, significant changes were detectable among individual health centers less than one-half of the time because of small numbers of events.</p> <p>Conclusions</p> <p>The aggregate HDCC registries had both adequate reporting rates and power to detect significant changes in cancer screening, but not follow-up care. Different measures provided different answers about improvements in cancer screening; more definitive evaluation would require validation of the registries. Limits to the implementation and interpretation of practice registry measurement in the HDCC highlight challenges and opportunities for local and aggregate quality improvement activities.</p
Satellite Tracking Reveals Long Distance Coastal Travel and Homing by Translocated Estuarine Crocodiles, Crocodylus porosus
Crocodilians have a wide distribution, often in remote areas, are cryptic, secretive and are easily disturbed by human presence. Their capacity for large scale movements is poorly known. Here, we report the first study of post-release movement patterns in translocated adult crocodiles, and the first application of satellite telemetry to a crocodilian. Three large male Crocodylus porosus (3.1–4.5 m) were captured in northern Australia and translocated by helicopter for 56, 99 and 411 km of coastline, the last across Cape York Peninsula from the west coast to the east coast. All crocodiles spent time around their release site before returning rapidly and apparently purposefully to their capture locations. The animal that circumnavigated Cape York Peninsula to return to its capture site, travelled more than 400 km in 20 days, which is the longest homeward travel yet reported for a crocodilian. Such impressive homing ability is significant because translocation has sometimes been used to manage potentially dangerous C. porosus close to human settlement. It is clear that large male estuarine crocodiles can exhibit strong site fidelity, have remarkable navigational skills, and may move long distances following a coastline. These long journeys included impressive daily movements of 10–30 km, often consecutively
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