2,587 research outputs found
CO2 laser induced decomposition of freon 113
Irradiations were made on CCl2FCClF2, Freon 113, to see if the resulting decomposition was photochemical in nature. The irradiation source was Molectron 250, continuous wave, infrared laser operating in the single line mode. The wavelength of irradiation was varied over the range 9.473 µ to 9.734 µ. The pressure except one (in which the cell window broke). Relative rates of reaction were calculated for a constant power absorbed by the sample of 7.8 ± 4W. These relative rates were plotted against the irradiation wavelength. This was superimposed on a plot of the IR band for Freon 113 which was irradiated in this project. A difference in wavelength of 0.11 µ in the maximum of absorption of the IR band for Freon 113 and the maximum relative rate of reaction was found. This indicated that the fastest reaction occurs when the laser is tuned to a vibrational level transition other than the v = 0 to v = 1 transition. Thermal and photochemical models are discussed, but are rejected as possible mechanisms for the reaction observed in this project. A model combining thermal excitation and photochemical reaction is discussed. Despite some assumptions made, it is shown that this model explains the data well
Automated analysis of quantitative image data using isomorphic functional mixed models, with application to proteomics data
Image data are increasingly encountered and are of growing importance in many
areas of science. Much of these data are quantitative image data, which are
characterized by intensities that represent some measurement of interest in the
scanned images. The data typically consist of multiple images on the same
domain and the goal of the research is to combine the quantitative information
across images to make inference about populations or interventions. In this
paper we present a unified analysis framework for the analysis of quantitative
image data using a Bayesian functional mixed model approach. This framework is
flexible enough to handle complex, irregular images with many local features,
and can model the simultaneous effects of multiple factors on the image
intensities and account for the correlation between images induced by the
design. We introduce a general isomorphic modeling approach to fitting the
functional mixed model, of which the wavelet-based functional mixed model is
one special case. With suitable modeling choices, this approach leads to
efficient calculations and can result in flexible modeling and adaptive
smoothing of the salient features in the data. The proposed method has the
following advantages: it can be run automatically, it produces inferential
plots indicating which regions of the image are associated with each factor, it
simultaneously considers the practical and statistical significance of
findings, and it controls the false discovery rate.Comment: Published in at http://dx.doi.org/10.1214/10-AOAS407 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
The SERENDIP 2 SETI project: Current status
Over the past 30 years, interest in extraterrestrial intelligence has progressed from philosophical discussion to rigorous scientific endeavors attempting to make contact. Since it is impossible to assess the probability of success and the amount of telescope time needed for detection, Search for Extraterrestrial Intelligence (SETI) Projects are plagued with the problem of attaining the large amounts of time needed on the world's precious few large radio telescopes. To circumvent this problem, the Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations (SERENDIP) instrument operates autonomously in a piggyback mode utilizing whatever observing plan is chosen by the primary observer. In this way, large quantities of high-quality data can be collected in a cost-effective and unobtrusive manner. During normal operations, SERENDIP logs statistically significant events for further offline analysis. Due to the large number of terrestrial and near-space transmitters on earth, a major element of the SERENDIP project involves identifying and rejecting spurious signals from these sources. Another major element of the SERENDIP Project (as well as most other SETI efforts) is detecting extraterrestrial intelligence (ETI) signals. Events selected as candidate ETI signals are studied further in a targeted search program which utilizes between 24 to 48 hours of dedicated telescope time each year
Systemic Insecticides Control Cattle Grubs
Systemic grub killers now available are effective in controlling cattle grubs when used as recommended. In tests, better gain on less feed and higher market returns more than offset the cost of treatment
Growth rates of interface-feeding spionid polychaetes in simulated tidal currents
Most spionid polychaetes switch from surface deposit feeding to suspension feeding as current speed and the flux of suspended food increase. Previous experiments testing the effects of flow on the growth of facultative, interface feeders have been limited to very simplified flow regimes such as constant, unidirectional currents. To measure the growth of interface-feeding spionids in more realistic currents, we programmed two identical counter-rotating annular flumes to simulate two different semidiurnal tidal currents. Each regime included four speeds that varied in hourly steps. At 5 mm above bottom, speeds in the slower flow regime were 0, 2.5, 5, and 7.5 cm s−1. Speeds in the faster regime were 0, 4, 8, and 12 cm s−11. Every 6 h, after each hour at 0 cm s−11, the flume rotation was reversed to simulate the directional shift between ebb and flood currents. The 12-h periods were repeated over 96 h. The experiment included eight 4-d runs of paired slow- and fast-flow flumes. Field-collected sediment and a nonliving algal slurry were added to control deposited and suspended food. Individuals of four species were measured for body volumes before and after each 4-d run: Polydora cornuta, Streblospio benedicti, Pygospio elegans, and Spio setosa. Each species except S. setosa was divided a priori into two size classes. Both small and large P. cornuta grew significantly faster in the fast-flow regime. Large P. elegans grew significantly faster in the fast-flow regime, but the growth rates of small P. elegans did not differ between regimes. Neither size class of S. benedicti grew at significantly different rates between flow regimes, and the broad size class of S. setosa did not show significant flow-dependent growth. The significant growth responses of two of the four species to moderate differences in tidal flow over a short time period underscore the impact flow can have on the population dynamics of some interface-feeding spionids. The differences among species suggest that variability in tidal currents can influence the structure and dynamics of communities in which spionids are often important and abundant
Cancer as a Chronic Disease
Cancers which were once fatal are increasingly able to be managed as chronic diseases. While most metastatic cancers in adults may not be curable, they often can be controlled for long periods of time with a succession of treatments. In this chapter in Cancer Concepts: A Guidebook for the Non-Oncologist, we will examine those cancers with longer natural histories and those with extended survivals due to therapeutic advances. Finally, several cases will be presented that exemplify this new paradigm of cancer as a chronic disease.https://escholarship.umassmed.edu/cancer_concepts/1028/thumbnail.jp
Heat storage capability of a rolling cylinder using Glauber's salt
The rolling cylinder phase change heat storage concept was developed to the point where a prototype design is completed and a cost analysis is prepared. A series of experimental and analytical tasks are defined to establish the thermal, mechanical, and materials behavior of rolling cylinder devices. These tasks include: analyses of internal and external heat transfer; performance and lifetime testing of the phase change materials; corrosion evaluation; development of a mathematical model; and design of a prototype and associated test equipment
Endothelin-1 mediates Aspergillus fumigatus induced airway inflammation and remodelling
BACKGROUND: Asthma is a chronic inflammatory condition of the airways and patients sensitised to airborne fungi such as Aspergillus fumigatus have more severe asthma. Thickening of the bronchial subepithelial layer is a contributing factor to asthma severity for which no current treatment exists. Airway epithelium acts as an initial defence barrier to inhaled spores, orchestrating an inflammatory response and contributing to subepithelial fibrosis.
OBJECTIVE: We aimed to analyse the production of profibrogenic factors by airway epithelium in response to A. fumigatus, in order to propose novel anti-fibrotic strategies for fungal-induced asthma.
METHODS: We assessed the induction of key profibrogenic factors, TGFβ1, TGFβ2, periostin and endothelin-1, by human airway epithelial cells and in mice exposed to A. fumigatus spores or secreted fungal factors.
RESULTS: A. fumigatus specifically caused production of endothelin-1 by epithelial cells in vitro but not any of the other profibrogenic factors assessed. A. fumigatus also induced endothelin-1 in murine lungs, associated with extensive inflammation and airway wall remodelling. Using a selective endothelin-1 receptor antagonist, we demonstrated for the first time, that endothelin-1 drives many features of airway wall remodelling and inflammation elicited by A. fumigatus.
CONCLUSION: Our findings are consistent with the hypothesis that elevated endothelin-1 levels contribute to subepithelial thickening and highlight this factor as a possible therapeutic target for difficult-to-treat fungal-induced asthma
The Effects of an Acute Bout of Self-Myofascial Release on the Physiological Parameters of Running
Please refer to the pdf version of the abstract located adjacent to the title
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