532 research outputs found
Recursive Detection and Analysis of Nanoparticles in Scanning Electron Microscopy Images
In this study, we present a computational framework tailored for the precise
detection and comprehensive analysis of nanoparticles within scanning electron
microscopy (SEM) images. The primary objective of this framework revolves
around the accurate localization of nanoparticle coordinates, accompanied by
secondary objectives encompassing the extraction of pertinent morphological
attributes including area, orientation, brightness, and length.
Constructed leveraging the robust image processing capabilities of Python,
particularly harnessing libraries such as OpenCV, SciPy, and Scikit-Image, the
framework employs an amalgamation of techniques, including thresholding,
dilating, and eroding, to enhance the fidelity of image processing outcomes.
The ensuing nanoparticle data is seamlessly integrated into the RStudio
environment to facilitate meticulous post-processing analysis. This encompasses
a comprehensive evaluation of model accuracy, discernment of feature
distribution patterns, and the identification of intricate particle
arrangements. The finalized framework exhibits high nanoparticle identification
within the primary sample image and boasts 97\% accuracy in detecting particles
across five distinct test images drawn from a SEM nanoparticle dataset.
Furthermore, the framework demonstrates the capability to discern nanoparticles
of faint intensity, eluding manual labeling within the control group.Comment: 9 pages, 10 figure
VLBI observations of the Crab nebula pulsar
Observations were made at meter wave-lengths using very long base-line interferometry techniques. At 196.5 MHz no resolution of the pulsar are observed; all the pulse shapes observed with the interferometers are similar to single dish profiles, and all the power pulsates. At 111.5 MHz besides the pulsing power there is always a steady component, presumably due to interstellar scattering. The pulsar is slightly resolved at 111.5 MHz with an apparent angular diameter of 0.07 sec ? 0.01 sec. A 50 percent linear polarization of the time-averaged power is noted at 196.5 MHz; at 111.5 MHz, 20 percent of the total time-averaged power is polarized, 35 percent of the pulsing power is polarized, and the steady component is unpolarized
Laser Applications
Contains research objectives and reports on three research projects.Joint Services Electronics Programs (U. S. Army, U. S. Navy, and U. S. Air Force) under Contract DAAB07-71-C-0300U. S. Air Force Office of Scientific Research (Contract F44620-71-C-0051)Naval Air Systems Comman
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Soft power, hard news:How journalists at state-funded transnational media legitimize their work
How do journalists working for different state-funded international news organizations legitimize their relationship to the governments which support them? In what circumstances might such journalists resist the diplomatic strategies of their funding states? We address these questions through a comparative study of journalists working for international news organizations funded by the Chinese, US, UK and Qatari governments. Using 52 interviews with journalists covering humanitarian issues, we explain how they minimized tensions between their diplomatic role and dominant norms of journalistic autonomy by drawing on three – broadly shared – legitimizing narratives, involving different kinds of boundary-work. In, the first ‘exclusionary’ narrative, journalists differentiated their ‘truthful’ news reporting from the ‘false’ state ‘propaganda’ of a common Other, the Russian-funded network, RT. In the second ‘fuzzifying’ narrative, journalists deployed the ambiguous notion of ‘soft power’ as an ambivalent ‘boundary concept’, to defuse conflicts between journalistic and diplomatic agendas. In the final ‘inversion’ narrative, journalists argued that, paradoxically, their dependence on funding states gave them greater ‘operational autonomy’. Even when journalists did resist their funding states, this was hidden or partial, and prompted less by journalists’ concerns about the political effects of their work, than by serious threats to their personal cultural capital
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NEW METHOD FOR REMOVAL OF SPECTRAL INTERFERENCES FOR BERYLLIUM ASSAY USING INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROMETRY
Beryllium has been used widely in specific areas of nuclear technology. Frequent monitoring of air and possible contaminated surfaces in U.S Department of Energy (DOE) facilities is required to identify potential health risks and to protect DOE workers from beryllium-contaminated dust. A new method has been developed to rapidly remove spectral interferences prior to beryllium (Be) measurement by inductively-coupled plasma atomic emission spectrometry (ICP-AES). The ion exchange separation removes uranium (U), thorium (Th), niobium (Nb), vanadium (V), molybdenum (Mo), zirconium (Zr), tungsten (W), iron (Fe), chromium (Cr), cerium (Ce), erbium (Er) and titanium (Ti). A stacked column consisting of Diphonix Resin{reg_sign} and TEVA Resin{reg_sign} reduces the levels of the spectral interferences so that low level Be measurements can be performed accurately. If necessary, an additional anion exchange separation can be used for further removal of interferences, particularly chromium. The method has been tested using spiked filters, spiked wipe samples and certified reference material standards with high levels of interferences added. The method provides very efficient removal of spectral interferences with very good accuracy and precision for beryllium on filters or wipes. A vacuum box system is employed to reduce analytical time and reduce labor costs
Rate of tarsal and metatarsal bone mineral density change in adults with diabetes mellitus and peripheral neuropathy: A longitudinal study
BACKGROUND: In people with diabetes (DM) and peripheral neuropathy (PN), loss of bone mineral density (BMD) in the tarsals and metatarsals contribute to foot complications; however, changes in BMD of the calcaneal bone is most commonly reported. This study reports rate of change in BMD of all the individual bones in the foot, in participants with DM and PN. Our aim was to investigate whether the rate of BMD change is similar across all the bones of the foot.
METHODS: Participants with DM and PN (n = 60) were included in this longitudinal cohort study. Rate of BMD change of individual bones was monitored using computed tomography at baseline and 6 months, 18 months, and 3-4 years from baseline. Personal factors (age, sex, medication use, step count, sedentary time, and PN severity) were assessed. A random coefficient model estimated rate of change of BMD in all bones and Pearson correlation tested relationships between personal factor variables and rate of BMD change.
RESULTS: Mean and calcaneal BMD decreased over the study period (p \u3c 0.05). Individual tarsal and metatarsal bones present a range of rate of BMD change (-0.3 to -0.9%/year) but were not significantly different than calcaneal BMD change. Only age showed significant correlation with BMD and rate of BMD change.
CONCLUSION: The rate of BMD change did not significantly differ across different foot bones at the group level in people with DM and PN without foot deformity. Asymmetric BMD loss between individual bones of the foot and aging may be indicators of pathologic changes and require further investigation.
TRIAL REGISTRATION: Metatarsal Phalangeal Joint Deformity Progression-R01. Registered 25 November 2015, https://clinicaltrials.gov/ct2/show/NCT02616263
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Providing rural public services : leadership and organizational considerations
Objectives
The research project from which this publicaÂtion stems, "Institutional Structures for Improving Rural Community Services," proposed to identify those leadership and organizational variables which might be altered to improve the institutional strucÂtures for providing public services to rural areas. Implicitly, the project proposal recognized that many declining rural communities will continue to decline. The objective was not to identify means of proÂmoting economic or industrial development in rural communities of the nation; rather, researchers atÂtempted to identify means by which the quality and range of rural public services might be improved by manipulating or altering the institutions through which services are provided. Accordingly, the obÂjective of this document is to discuss some of the leadership and organizational considerations which influence the provision of rural public services.Published December 1975. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo
High resolution observations of Cassiopeia A at meter wavelengths
Very long baseline interferometric (VLBI) observations of the supernova remnant Cassiopeia A, at 74 MHz with a 12,000-wavelength baseline and at 111 MHz with a 18,500-wavelength baseline, are reported. The fringe amplitudes are strongly varying on a time scale of about 15 to 30 minutes. The location of the extra source must lie outside the supernova remnant shell possibly associated with a concentration of emission north of the shell, or lying outside the gap in the northeastern side of the shell. The flux and spectral index deduced for the compact source depend on the assumed size, with a range of 100 Jy to 500 Jy at 74 MHz. If the source is associated with the supernova explosion, it must have been traveling at least 5000 km s/2
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