5,606 research outputs found
Children’s Health and Environmental Exposure Risks: Information Gaps, Scientific Uncertainty, and Regulatory Reform
An Evaluation of an Avian Diversity Model
Diversity exists at all temporal and spatial scales but has been studied largely at the community level because of the limited availability of regional or nation-wide data. In the U.S. both the Breeding Bird Survey (BBS) and the Breeding Bird Census (BBC) provide large-scale observations of avian populations over periods of decades and offer a potential source of information. A large-scale model of avian diversity based on the BBS has been developed by O\u27Connor et. al.(1996). The BBC serves as a source for independently obtained species richness estimates used to evaluate the ability of the model to generate corresponding predictions. Overall, the species richness estimates obtained from the BBC data were consistently less than the model predictions. Differences between the BBC and BBS sampling methods offer an explanation for this bias. The BBC data set suffered many limitations; however, when species richness estimates were obtained from the sites representative of the surrounding habitat, the model offered the strongest correlation
A multiswitchable poly(terthiophene) bearing a spiropyran functionality: understanding photo and electrochemical control
An electroactive nitrospiropyran-substituted polyterthiophene, 2-(3,3′′-dimethylindoline-6′-nitrobenzospiropyranyl)ethyl 4,4′′-didecyloxy-2,2′:5′,2′′-terthiophene-3′-acetate, has been synthesized for the first time. The spiropyran, incorporated into the polymer backbone by covalent attachment to the alkoxyterthiophene monomer units, leads to multiple coloured states as a result of both electrochemical isomerization of the spiropyran moiety to merocyanine forms as well as electrochemical oxidation of the polyterthiophene backbone and the merocyanine substituents. While electrochemical polymerization of the terthiophene monomer could occurs without the apparent oxidation of the spiropyran, the subsequent electrochemistry is complex and clearly involves this substituent. In order to understand this complex behaviour, the first detailed electrochemical study of the oxidation of the precursor spiropyran, 1-(2-hydroxyethyl)-3,3-dimethylindoline-6’-nitrobenzospiropyran, was undertaken, showing that, in solution, an irreversible electrochemical oxidation of the spiropyran occurs leading to reversible redox behaviour of at least two merocyanine isomers. With these insights, an extensive electrochemical and spectroelectrochemical study of the nitrospiropyran-substituted polyterthiophene films reveals an initial irreversible electrochemical oxidative ring opening of the spiropyran to oxidized merocyanine. Subsequent reduction and cyclic voltammetry of the resulting nitromerocyanine-substituted polyterthiophene film gives rise to the formation of both merocyanine π-dimers or oligomers and π-radical cation dimers, between polymer chains. Although merocyanine formation is not electrochemically reversible, the spiropyran can be photochemically regenerated, at least in part, through irradiation with visible light. SEM and AFM images support the conclusion that the bulky spiropyran substituent is electrochemically isomerizes to the planar merocyanine moiety affording a smoother polymer film. The conductivity of the freestanding polymer film was found to be 0.4 S cm-1
The Feasibility of Dynamically Granted Permissions: Aligning Mobile Privacy with User Preferences
Current smartphone operating systems regulate application permissions by
prompting users on an ask-on-first-use basis. Prior research has shown that
this method is ineffective because it fails to account for context: the
circumstances under which an application first requests access to data may be
vastly different than the circumstances under which it subsequently requests
access. We performed a longitudinal 131-person field study to analyze the
contextuality behind user privacy decisions to regulate access to sensitive
resources. We built a classifier to make privacy decisions on the user's behalf
by detecting when context has changed and, when necessary, inferring privacy
preferences based on the user's past decisions and behavior. Our goal is to
automatically grant appropriate resource requests without further user
intervention, deny inappropriate requests, and only prompt the user when the
system is uncertain of the user's preferences. We show that our approach can
accurately predict users' privacy decisions 96.8% of the time, which is a
four-fold reduction in error rate compared to current systems.Comment: 17 pages, 4 figure
Common Lunar Lander (CLL) trajectory analysis
Common Lunar Lander trajectory analysis is presented in viewgraph format. Trajectory requirements, trajectory characteristics, trajectory timeline, and alternate trajectory advantages and disadvantages are given
Copper and zinc balance in exercising horses fed two forms of mineral supplements
This study was undertaken to compare the absorption and retention of copper and zinc when supplemented to exercising horses in the form of sulfate or organic-chelate mineral supplements. Nine mature horses were used in a modified-switchback designed experiment consisting of seven 28-d periods. Horses were fed a diet consisting of 50% coastal Bermudagrass and 50% concentrate. All diets were balanced to meet the energy, protein, calcium and phosphorus requirements for horses performing moderate to intense exercise. Copper and zinc supplementation varied by period. During mineral depletion and repletion periods, horses respectively consumed diets with no supplemental mineral or Cu and Zn supplemented in the sulfate form to provide 100% of NRC (1989) values. In periods 4 and 7, horses were fed diets designed to provide 90% of NRC (1989) values for Cu and Zn supplied in the sulfate or organic-chelate forms. Horses were subjected to a standard exercise test on d 23 of periods 4 and 7 followed by a 4-d total fecal and urine collection. Blood samples were drawn every 28-d for determination of plasma Cu, Zn and ceruloplasmin concentration, and white blood cell counts and Cu,Zn-superoxide dismutase activity were evaluated in periods 4 and 7. Copper and zinc balance was determined from feed, fecal, urine and water samples obtained during the total collections in periods 4 and 7. Copper and Zn intake and fecal excretion were greater (P<0.05) for horses consuming the organic-chelate supplemented diet. Apparent Cu absorption as a percent of intake and retention as a percent of intake were also greater for this group. Plasma Cu, Zn and ceruloplasmin concentration was not different for horses consuming the two mineral supplement forms. White blood cell counts and superoxide dismutase activity were not affected by diet treatment. Formulation error and suspected sample contamination made it difficult to compare absorption and retention of Cu and Zn, but the use of a controlled repletion-depletion diet sequence appeared to be an effective experimental design component
Summit Trio and Friends
The Summit Trio presents a very special recital featuring Brahms\u27 epic Piano Quintet in F minor (Op. 34). Perhaps one of the most beloved pieces of chamber music, this is the first time the work will be performed at Kennesaw State. Summit Trio is violinist Helen Kim (Professor of Violin), cellist Charae Krueger (Artist-in-Residence and Lecturer of Cello), and pianist Robert Henry (Director of Piano Studies and Assistant Professor of Music) with KSU faculty guests Kenn Wagner, violin, and Cathy Lynn, viola.https://digitalcommons.kennesaw.edu/musicprograms/2115/thumbnail.jp
Faculty Chamber Players
KSU faculty violinists Helen Kim and Kenn Wagner, violists Cathy Lynn and Paul Murphy, and cellist Charae Krueger perform Mozart\u27s String Quintet in C Minor, K. 406, and Dvořák\u27s String Quintet in E-flat Major, Op. 97 ( American ).https://digitalcommons.kennesaw.edu/musicprograms/1002/thumbnail.jp
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