230 research outputs found
Evangelical Christians in Canadian National Television News, 1994–2004: A Frame Analysis
Recent surveys have shown that most evangelical Christians in Canada believe that the news media treat them unfairly. This study empirically tested the validity of the evangelicals’ charge against the media by examining the frames used in the nightly, national news reports of Global, CBC and CTV television networks. An analysis of all reports featuring evangelicals showed that neutral and positive frames, together, were almost equal in strength and number to negative frames used; this resulted in an overall rating of “balanced” for the coverage.
While overall the coverage was balanced, the frequency and exclusivity of certain negative frames elevated their saliency considerably. For example, the “evangelicals as intolerant” frame alone appeared in one quarter of all reports. Regarding topic of the news reports, evangelicals most often received coverage for involvement in politics followed closely by involvement in criminal or immoral actions. Implications of these results are discussed
Nuclear Equation of State from Observations of Short Gamma-Ray Burst Remnants
The favoured progenitor model for short -ray bursts (SGRBs) is the
merger of two neutron stars that triggers an explosion with a burst of
collimated -rays. Following the initial prompt emission, some SGRBs
exhibit a plateau phase in their -ray light curves that indicates additional
energy injection from a central engine, believed to be a rapidly rotating,
highly magnetised neutron star. The collapse of this `protomagnetar' to a black
hole is likely to be responsible for a steep decay in -ray flux observed at
the end of the plateau. In this letter, we show that these observations can be
used to effectively constrain the equation of state of dense matter. In
particular, we show that the known distribution of masses in binary neutron
star systems, together with fits to the -ray light curves, provide
constraints that exclude the softest and stiffest plausible equations of state.
We further illustrate how a future gravitational wave observation with Advanced
LIGO/Virgo can place tight constraints on the equation of state, by adding into
the picture a measurement of the chirp mass of the SGRB progenitor.Comment: accepted for publication in Phys. Rev.
Limits to Performance Improvement Provided by Balanced Interferometers and Balanced Detection in OCT/OCM Instruments
We compare the dynamic range of OCT/OCM instruments configured with unbalanced interferometers, e.g., Michelson interferometers, with that of instruments utilizing balanced interferometers and balanced photodetection. We define the dynamic range (DR) as the ratio of the maximum fringe amplitude achieved with a highly reflecting surface to the root-mean-square (rms) noise. Balanced systems achieve a dynamic range 2.5 times higher than that of a Michelson interferometer, enabling an image acquisition speed roughly 6 times faster. This maximum improvement occurs at light source powers of a few milliwatts. At light source powers higher than 30 mW, the advantage in acquisition speed of balanced systems is reduced to a factor of 4. For video-rate imaging, the increased cost and complexity of a balanced system may be outweighed by the factor of 4 to 6 enhancement in image acquisition speed. We include in our analysis the beat-noise resulting from incoherent fight backscattered from the sample, which reduces the advantage of balanced systems. We attempt to resolve confusion surrounding the origin and magnitude of beat-noise , first described by L. Mandel in 1962. Beat-noise is present in both balanced and unbalanced OCT/OCM instruments
Role of Beat Noise in Limiting the Sensitivity of Optical Coherence Tomography
The sensitivity and dynamic range of optical coherence tomography (OCT) are calculated for instruments utilizing two common interferometer configurations and detection schemes. Previous researchers recognized that the performance of dual-balanced OCT instruments is severely limited by beat noise, which is generated by incoherent light backscattered from the sample. However, beat noise has been ignored in previous calculations of Michelson OCT performance. Our measurements of instrument noise confirm the presence of beat noise even in a simple Michelson interferometer configuration with a single photodetector. Including this noise, we calculate the dynamic range as a function of OCT light source power, and find that instruments employing balanced interferometers and balanced detectors can achieve a sensitivity up to six times greater than those based on a simple Michelson interferometer, thereby boosting image acquisition speed by the same factor for equal image quality. However, this advantage of balanced systems is degraded for source powers greater than a few milliwatts. We trace the concept of beat noise back to an earlier paper [J. Opt. Soc. Am. 52, 1335 (1962)]
The effects of exurbanization on the food and habitat of pileated woodpeckers
*Background/Question/Methods* 
_Dryocopus pileatus_ (pileated woodpeckers) are the largest woodpeckers in the United States. They require large trees for roosting, nesting, and feeding and these trees must be dead or dying for ease of excavation and presence of the woodpeckers' main prey of ants and grubs. Because of these habitat requirements, pileated woodpeckers are used as an indicator species for mature forests. However, their status in exurban areas, or places of low-density development beyond the suburban fringe, is poorly known. Because exurbanization covers a large and growing portion of the eastern U.S.A., we examined how pileated woodpeckers and their habitat vary across a gradient of exurbanization. We tested the hypothesis that presence of pileated woodpeckers is positively correlated with forest structure and food availability, in exurban and forested areas. We conducted the study in Sewanee, Tennessee, U.S.A., establishing 30 randomly located sample points evenly divided between exurban and forested areas. At each point we assessed pileated woodpecker presence through visual and vocal surveys; forest structure through measures of downed wood, standing trees, and understory density; and food availability through presence of ants and grubs in soil cores and pitfall traps.

*Results/Conclusions* 
We found no difference between the presence of pileated woodpeckers, amount and rot class of dead wood, and ant and grub abundance between exurban and forested areas. Mean tree diameter was larger in exurban areas most likely because many small trees had been removed by human landscaping. These data suggest that some exurban areas may provide habitat for pileated woodpeckers. However, more studies are needed to examine the breeding success and survival rates of pileated woodpeckers in exurban and forested areas. Because the mature forest characteristics that pileated woodpeckers prefer can be found in exurban areas, it is possible that other species requiring these characteristics could also find usable habitat in exurban areas. This could apply most specifically to those secondary cavity-nesting species that use old pileated woodpecker nesting cavities. More studies should be conducted to further explore the effects of exurbanization on other species that are thought of as indicating mature forests
Intrinsic calf factors associated with the behavior of healthy pre-weaned group-housed dairy-bred calves
Technology-derived behaviors are researched for disease detection in artificially-reared calves. Whilst existing studies demonstrate differences in behaviors between healthy and diseased calves, intrinsic calf factors (e.g., sex and birthweight) that may affect these behaviors have received little systematic study. This study aimed to understand the impact of a range of calf factors on milk feeding and activity variables of dairy-bred calves. Calves were group-housed from ~7 days to 39 days of age. Seven liters of milk replacer was available daily from an automatic milk feeder, which recorded feeding behaviors and live-weight. Calves were health scored daily and a tri-axial accelerometer used to record activity variables. Healthy calves were selected by excluding data collected 3 days either side of a poor health score or a treatment event. Thirty-one calves with 10 days each were analyzed. Mixed models were used to identify which of live-weight, age, sex, season of birth, age of inclusion into the group, dam parity, birthweight, and sire breed type (beef or dairy), had a significant influence on milk feeding and activity variables. Heavier calves visited the milk machine more frequently for shorter visits, drank faster and were more likely to drink their daily milk allowance than lighter calves. Older calves had a shorter mean standing bout length and were less active than younger calves. Calves born in summer had a longer daily lying time, performed more lying and standing bouts/day and had shorter mean standing bouts than those born in autumn or winter. Male calves had a longer mean lying bout length, drank more slowly and were less likely to consume their daily milk allowance than their female counterparts. Calves that were born heavier had fewer lying and standing bouts each day, a longer mean standing bout length and drank less milk per visit. Beef-sired calves had a longer mean lying bout length and drank more slowly than their dairy sired counterparts. Intrinsic calf factors influence different healthy calf behaviors in different ways. These factors must be considered in the design of research studies and the field application of behavior-based disease detection tools in artificially reared calves
Thermal Links for the Implementation of an Optical Refrigerator
Optical refrigeration has been demonstrated by several groups of researchers, but the cooling elements have not been thermally linked to realistic heat loads in ways that achieve the desired temperatures. The ideal thermal link will have minimal surface area, provide complete optical isolation for the load, and possess high thermal conductivity. We have designed thermal links that minimize the absorption of fluoresced photons by the heat load using multiple mirrors and geometric shapes including a hemisphere, a kinked waveguide, and a tapered waveguide. While total link performance is dependent on additional factors, we have observed net transmission of photons with the tapered link as low as 0.04%. Our optical tests have been performed with a surrogate source that operates at 625 nm and mimics the angular distribution of light emitted from the cooling element of the Los Alamos solid state optical refrigerator. We have confirmed the optical performance of our various link geometries with computer simulations using CODE V optical modeling software. In addition we have used the thermal modeling tool in COMSOL MULTIPHYSICS to investigate other heating factors that affect the thermal performance of the optical refrigerator. Assuming an ideal cooling element and a nonabsorptive dielectric trapping mirror, the three dominant heating factors are (1) absorption of fluoresced photons transmitted through the thermal link, (2) blackbody radiation from the surrounding environment, and (3) conductive heat transfer through mechanical supports. Modeling results show that a 1 cm3 load can be chilled to 107 K with a 100Wpump laser. We have used the simulated steady-state cooling temperatures of the heat load to compare link designs and system configurations
Ecological implications of a flower size/number trade-off in tropical forest trees
Peer reviewedPublisher PD
Evaluating the Suitability of Using Rat Models for Preclinical Efficacy and Side Effects with Inhaled Corticosteroids Nanosuspension Formulations
Inhaled corticosteroids (ICS) are often prescribed as first-line therapy for patients with asthma Despite their efficacy and improved safety profile compared with oral corticosteroids, the potential for systemic side effects continues to cause concern. In order to reduce the potential for systemic side effects, the pharmaceutical industry has begun efforts to generate new drugs with pulmonary-targeted topical efficacy. One of the major challenges of this approach is to differentiate both efficacy and side effects (pulmonary vs. systemic) in a preclinical animal model. In this study, fluticasone and ciclesonide were used as tool compounds to explore the possibility of demonstrating both efficacy and side effects in a rat model using pulmonary delivery via intratracheal (IT) instillation with nanosuspension formulations. The inhibition of neutrophil infiltration into bronchoalveolar lavage fluid (BALF) and cytokine (TNFα) production were utilized to assess pulmonary efficacy, while adrenal and thymus involution as well as plasma corticosterone suppression was measured to assess systemic side effects. Based on neutrophil infiltration and cytokine production data, the ED50s for ciclesonide and fluticasone were calculated to be 0.1 and 0.03 mg, respectively. At the ED50, the average adrenal involution was 7.6 ± 5.3% for ciclesonide versus 16.6 ± 5.1% for fluticasone, while the average thymus involution was 41.0 ± 4.3% for ciclesonide versus 59.5 ± 5.8% for fluticasone. However, the differentiation became less significant when the dose was pushed to the EDmax (0.3 mg for ciclesonide, 0.1 mg for fluticasone). Overall, the efficacy and side effect profiles of the two compounds exhibited differentiation at low to mid doses (0.03–0.1 mg ciclesonide, 0.01–0.03 mg fluticasone), while this differentiation diminished at the maximum efficacious dose (0.3 mg ciclesonide, 0.1 mg fluticasone), likely due to overdosing in this model. We conclude that the rat LPS model using IT administration of nanosuspensions of ICS is a useful tool to demonstrate pulmonary-targeted efficacy and to differentiate the side effects. However, it is only suitable at sub-maximum efficacious levels
Primary Prevention of Gestational Diabetes Mellitus and Large-for-Gestational-Age Newborns by Lifestyle Counseling: A Cluster-Randomized Controlled Trial
In a cluster-randomized trial, Riitta Luoto and colleagues find that counseling on diet and activity can reduce the birthweight of babies born to women at risk of developing gestational diabetes mellitus (GDM), but fail to find an effect on GDM
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