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Aquatic studies at the 100-HR-3 and 100-NR-1 operable units
Pacific Northwest Laboratory initiated a program to characterize selected aquatic biological populations to determine (1) existing levels of inorganic chemical and radionuclide contamination, and (2) the populations' suitability as indicators of chemical releases during cleanup activities at the US Department of Energy's Hanford Site. Following work plans for the ground-water operable units, lower trophic levels in the aquatic habitat (periphyton and caddisfly larvae) were evaluated for contaminants at the 100-HR-3 Operable Unit and 100-NR-1 Operable Unit. The results were evaluated to determine the need for further sampling. If the results showed no significant contamination compared to upriver levels, sampling would be discontinued. The periphyton community appears to be suitable for determining contamination levels. Baseline concentrations for stable chromium were established and will be useful for comparing samples collected when contaminant release is expected. Concentrations of [sup 60]Co, [sup 90]Sr, and [sup 137]Cs in periphyton were essentially below detectable limits, which will also make this community useful in detecting potential releases of radionuclides during cleanup activities. Levels for both stable chromium and radionuclides were essentially below detection limits for caddisfly larvae. Thus, these organisms may be used to monitor suspected contaminant releases from cleanup activities; if concentrations exceed detection limits, they may be related to these activities. Two candidate threatened and endangered species of molluscs occur in the Hanford Reach of the Columbia River. These are the shortface lanx (Fisherola nuttalli), which is a Washington State candidate species, and the Columbia pebblesnail (Fluminicola columbiana), which is both a state and federal candidate species. Specimens of the shortface lanx were observed in the vicinity of N Springs (100-NR-1 Operable Unit); they likely occur throughout this area
On the stability and spectral radius of a finite set of matrices
This paper studies some problems related to the stability and the spectral radius of a finite set of matrices. A seasonal epidemic model is given to illustrate the use of the obtained results. In this example, the relationship between the obtained results and the stability of a discrete time periodic linear system is obtained.This work has been partially supported by Spanish [grant number MTM2013-43678-P].Cantó Colomina, B.; Coll, C.; Sánchez, E. (2016). On the stability and spectral radius of a finite set of matrices. Linear and Multilinear Algebra. 64(3):353-361. https://doi.org/10.1080/03081087.2015.1040404S35336164
2MASS J06164006-6407194: The First Outer Halo L Subdwarf
We present the serendipitous discovery of an L subdwarf, 2MASS
J06164006-6407194, in a search of the Two Micron All Sky Survey for T dwarfs.
Its spectrum exhibits features indicative of both a cool and metal poor
atmosphere including a heavily pressured-broadened K I resonant doublet, Cs I
and Rb I lines, molecular bands of CaH, TiO, CrH, FeH, and H2O, and enhanced
collision induced absorption of H2. We assign 2MASS 0616-6407 a spectral type
of sdL5 based on a comparison of its red optical spectrum to that of near
solar-metallicity L dwarfs. Its high proper motion (mu =1.405+-0.008 arcsec
yr-1), large radial velocity (Vrad = 454+-15 km s-1), estimated uvw velocities
(94, -573, 125) km s-1 and Galactic orbit with an apogalacticon at ~29 kpc are
indicative of membership in the outer halo making 2MASS 0616-6407 the first
ultracool member of this population.Comment: Accepted for publication in Ap
Spin-dependent Bohm trajectories associated with an electronic transition in hydrogen
The Bohm causal theory of quantum mechanics with spin-dependence is used to
determine electron trajectories when a hydrogen atom is subjected to
(semi-classical) radiation. The transition between the 1s ground state and the
2p0 state is examined. It is found that transitions can be identified along
Bohm trajectories. The trajectories lie on invariant hyperboloid surfaces of
revolution in R^3. The energy along the trajectories is also discussed in
relation to the hydrogen energy eigenvalues.Comment: 18 pages, 8 figure
Parents’ Perspectives on the Theoretical Domains Framework Elements Needed in a Pediatric Health Behavior App: A Crowdsourced Social Validity Study
A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Background: Most pediatric studies do not include parent stakeholders in the design of the intervention itself and many pediatric
mobile health (mHealth) interventions are not meaningfully disseminated after the trial period ends. Consequently, the consumer
desire for mobile apps targeting pediatric health behavior is likely to be met by commercial products that are not based in theory
or evidence and may not take stakeholder preferences into account.
Objective: The aim was to assess parent preference for mobile app features that map onto specific Theoretical Domains
Framework (TDF) elements.
Methods: This study was a crowdsourced social validity study of 183 parents who were asked to rate their preferences for
mobile app features that correspond to elements of the TDF. The TDF organizes a large number of theoretical models and
constructs into three components: (1) capability, (2) motivation, and (3) opportunity. Parents of children were recruited through
Amazon Mechanical Turk.
Results: The majority of participants were Caucasian and mean age was 36.9 (SD 8.0) years. Results revealed broad acceptability
of communication, motivation, and opportunity domains. However, the degree to which each domain was valued varied within
behavioral category. Parents demonstrated a preference for increasing procedural knowledge for physical activity and diet behaviors
over sleep (F2,545=5.18, P=.006). Similarly, parents valued self-monitoring as more important for physical activity than sleep
(F2,546=4.04, P=.02). When asked about the value of features to help children develop skills, parents preferred those features for
dietary behavior over sleep (F2,546=3.57, P=.03). Parents perceived that goal-setting features would be most useful for physical
activity over sleep and diet (F2,545=5.30, P=.005). Incentive features within the app were seen as most useful for physical activity
over sleep (F2,546=4.34, P=.01).
Conclusions: This study presents a low-cost strategy for involving a large number of stakeholders in the discussion of how
health behavior theory should be applied in a mHealth intervention. Our approach is innovative in that it took a scientific framework
(ie, TDF) and made it digestible to parents so that they could then provide their opinions about features that might appear in a
future app. Our survey items discriminated between various health behaviors allowing stakeholders to communicate the different
health behaviors that they would like a TDF feature to change. Moreover, we were able to develop a set of consumer opinions
about features that were directly linked to elements of the TDF
Near-Infrared Spectroscopy of McNeil's Nebula Object
We present 0.8-5.2 micron spectroscopy of the compact source at the base of a
variable nebula (McNeil's Nebula Object) in the Lynds 1630 dark cloud that went
into outburst in late 2003. The spectrum of this object reveals an extremely
red continuum, CO bands at 2.3-2.5 microns in emission, a deep 3.0 micron ice
absorption feature, and a solid state CO absorption feature at 4.7 microns. In
addition, emission lines of H, Ca II, Mg I, and Na I are present. The Paschen
lines exhibit P Cygni profiles, as do two lines of He I, although the emission
features are very weak in the latter. The Brackett lines, however, are seen to
be purely in emission. The P Cygni profiles clearly indicate that mass outflow
is occurring in a wind with a velocity of ~400 km/s. The H line ratios do not
yield consistent estimates of the reddening, nor do they agree with the
extinction estimated from the ice feature (A_V ~ 11). We propose that these
lines are optically thick and are produced in a dense, ionized wind. The
near-infrared spectrum does not appear similar to any known FUor or EXor
object. However, all evidence suggests that McNeil's Nebula Object is a
heavily-embedded low-mass Class I protostar, surrounded by a disk, whose
brightening is due to a recent accretion event.Comment: 11 pages, 2 ps figures, accepted for publication in ApJ Letter
An Updated Checklist of the Spiders (Arachnida: Araneae) of Arkansas
A total of 510 species of spiders representing 43 families and 215 genera are herein reported from Arkansas. The most diverse families of state spiders were Salticidae (64 species), Lycosidae (59 species), Araneidae (55 species), and Gnaphosidae (54 species). Twelve families had only a single representative species in the state. Additional taxa will surely be added to the checklist with future taxonomic studies incorporating molecular analyses and additional collecting. This updated checklist is intended to be of use to arachnologists, researchers, naturalists, professional biologists, and managers in determining the biodiversity for Arkansas. We have worked to insure that the taxonomy of the spiders documented in Arkansas is current and authoritative
CYCLING OF Zn IN A SIMPLE FOOD-WEB.
The present exoeriment was designed to investigate the cycling of Zn in a simple water-periphyton-fish food-web under constant flow light, and ambient radionuclide concentration
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