974 research outputs found
Revising the vision screening forms
School screenings are used to identify children with possible optometric concerns as well as serve as an educational tool for parents. In an effort to effectively screen schoolchildren, an intake form was composed to be taken home for the parent/guardian of the child to complete and return to the individual(s) conducting the screening. A form was also composed for the children to take home to their parents explaining the specific areas of screenings and in which area the child may have failed. The forms were designed to be simple and easy to understand
Groundwater characterization at Yucca Mountain task 2: Surface complexation and solid phase sorption
The purpose and scope of this report is to present an overview of the experiments, methods, results, and conclusions from research performed for the project “Groundwater Characterization at Yucca Mountain Task 2: Surface Complexation and Solid Phase Dissolution”. The impact of surface complexation, alteration phase formation, and solution competition with metal ions on the solubility and speciation of actinide elements (U, Pu, Np) will be examined. In particular the role of iron (as Fe2+ and Fe3+) and silicate (as SO3 2-) concentrations on speciation, solubility, sorption, and secondary phase formation of actinides will be investigated. While a large body of literature exists on the interaction of actinides with iron and iron oxide phases, relatively little has been explored regarding the impact of silicates on actinide speciation. Therefore the role of silicates will be the main focus of the report, as it is the primary factor which meaningfully contributes to the enhanced understanding of actinide environmental speciation. The described topics are examined through two main studies areas: formation of precipitates from solution phase species and sorption of dissolved species to solids. The main actinide ion species of interests are UO2 2+, NpO2 +, and Pu4+. These species were selected based on their importance as components of spent nuclear fuel and their potential to form soluble species. The main component of spent nuclear fuel is uranium; neptunium is expected to have a high solubility due to its pentavalent oxidation state, and plutonium may form colloidal species [1]. The aqueous phase pH, Fe concentration, and SiO3 2- concentration are varied. The role of Fe is of importance since canister corrosion may elevate aqueous levels of iron. Since the groundwater near the Yucca Mountain site is approaching saturation in silicate concentration, evaluation of this anion is deemed crucial. Furthermore, geochemical research at the Nevada Test Site has identified goethite and silicates as important geominerals, offering further motive for the investigation of iron oxides and silicates [2]. The role of pH is fundamental in dictating actinide and iron hydrolysis [3] and is evaluated to ascertain its importance in speciation in the presence of the other solution constituents. The project results will elucidate the relative importance of Fe and silicates in actinide speciation, in particular the formation of precipitates and subsequently sorbed species. The main focus will be on the role of silicate
Understanding Perceptions of Problematic Facebook Use: When People Experience Negative Life Impact and a Lack of Control
While many people use social network sites to connect with friends and
family, some feel that their use is problematic, seriously affecting their
sleep, work, or life. Pairing a survey of 20,000 Facebook users measuring
perceptions of problematic use with behavioral and demographic data, we
examined Facebook activities associated with problematic use as well as the
kinds of people most likely to experience it. People who feel their use is
problematic are more likely to be younger, male, and going through a major life
event such as a breakup. They spend more time on the platform, particularly at
night, and spend proportionally more time looking at profiles and less time
browsing their News Feeds. They also message their friends more frequently.
While they are more likely to respond to notifications, they are also more
likely to deactivate their accounts, perhaps in an effort to better manage
their time. Further, they are more likely to have seen content about social
media or phone addiction. Notably, people reporting problematic use rate the
site as more valuable to them, highlighting the complex relationship between
technology use and well-being. A better understanding of problematic Facebook
use can inform the design of context-appropriate and supportive tools to help
people become more in control.Comment: CHI 201
Continuous twin screw rheo-extrusion of an AZ91D magnesium alloy
© The Minerals, Metals & Materials Society and ASM International 2012The twin screw rheo-extrusion (TSRE) is designed to take advantage of the nondendritc microstructure and thixotropic characterization of semisolid-metal slurries and produce simple metal profiles directly from melts. The extrusion equipment consists of a rotor-stator high shear slurry maker, a twin screw extruder, and a die assembly. The process is continuous and has a potential for significantly saving energy, manufacturing cost, and enhancing efficiency. The present investigation was carried out to study the process performance for processing rods of an AZ91D magnesium alloy and the microstructure evolution during processing. The semisolid slurry prepared by the process was characterized by uniformly distributed nondendritic granular primary phase particles. AZ91D rods with uniform and fine microstructures and moderate mechanical properties were produced. For the given slurry making parameters, decreasing extrusion temperature was found to improve microstructures and properties. The mechanisms of particle granulation and refinement and the effect of processing parameters on process performance and thermal management are discussed. © 2012 The Minerals, Metals & Materials Society and ASM International.EPSRC (UK) and Rautomead Lt
Structural and environmental controls on Antarctic ice shelf rift propagation inferred from satellite monitoring
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102662/1/jgrf20163.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/102662/2/SupplementaryFigures_052513.pd
Wait-Learning: Leveraging Wait Time for Second Language Education
Competing priorities in daily life make it difficult for those with a casual interest in learning to set aside time for regular practice. In this paper, we explore wait-learning: leveraging brief moments of waiting during a person's existing conversations for second language vocabulary practice, even if the conversation happens in the native language. We present an augmented version of instant messaging, WaitChatter, that supports the notion of wait-learning by displaying contextually relevant foreign language vocabulary and micro-quizzes just-in-time while the user awaits a response from her conversant. Through a two week field study of WaitChatter with 20 people, we found that users were able to learn 57 new words on average during casual instant messaging. Furthermore, we found that users were most receptive to learning opportunities immediately after sending a chat message, and that this timing may be critical given user tendency to multi-task during waiting periods.Quanta Computer (Firm)Lincoln Laborator
Determination of the eta'-proton scattering length in free space
Taking advantage of both the high mass resolution of the COSY-11 detector and
the high energy resolution of the low-emittance proton-beam of the Cooler
Synchrotron COSY we determine the excitation function for the pp --> pp eta'
reaction close-to-threshold. Combining these data with previous results we
extract the scattering length for the eta'-proton potential in free space to be
Re(a_{p eta'}) = 0+-0.43 fm and Im(a_{p eta'}) = 0.37(+0.40)(-0.16) fm.Comment: 5 pages, 3 figures, accepted for publication in Phys. Rev. Let
Poly(3-alkylthiophenes): new sorption materials for solid phase microextraction of drugs isolated from human plasma
A novel sorbent in solid phase microextraction (SPME) method based on poly(3-alkylthiophenes) was used in the isolation of linezolid from human plasma samples following liquid chromatography determination. The effect of extraction time on the sorption capacity of the SPME process was studied and pointed at 10Â min both for adsorption and desorption. Poly(3-methylthiophene) and poly(3-nonylthiophene) were applied for the extraction of linezolid from water solutions. In plasma samples, four coatings including polythiophene and poly(3-penthylthiophene) were investigated. With these measurements, correlation coefficients were calculated in the range from 0.9820 to 0.9995, and the relative standard deviations were below 15%. That allowed claiming that the synthesized and described materials can be successfully applied in the analysis of linezolid also from other matrices such as urine or blood
Search for the 3He-eta bound state at COSY-11
We have measured excitation function for dp -> ppp_pi- reaction near the eta
production threshold. We observe an enhancement of the counting rate above the
threshold which can originate from the production of the eta meson in the
reaction dp -> 3He eta and its subsequent absorption on neutron in the 3He
nucleus leading to creation of the p_pi- pair.Comment: Presented at 10th International Workshop on Meson Production,
Properties and Interaction (MESON 2008), Cracow, Poland, 6 - 10 June 2008, 4
pages, 4 figures,references adde
Development of septic polysynovitis and uveitis in foals experimentally infected with \u3ci\u3eRhodococcus equi\u3c/i\u3e
Rhodococcus equi is one of the most important causes of disease in foals. Infection is typically characterized by pyogranulomatous pneumonia although extrapulmonary infections occur occasionally. Uveitis and polysynovitis have been reported in foals naturally infected with R. equi and are thought to be the result of an immune-mediated process. However, the pathogenesis of these conditions is poorly understood. The objectives of this study were to document the occurrence of uveitis and polysynovitis after experimental infection with R. equi and to determine if these disorders are the direct result of infection at these sites. Foals between 3 and 4 weeks of age were infected intratracheally with virulent R. equi using inocula of 1×108 CFU (high inoculum; n = 16) or 1×107 CFU (low inoculum; n = 12). Foals were monitored twice daily and necropsy was performed 14 days post-infection. Aqueous humor and synovial fluid were collected aseptically and the percentage of affected lung was calculated. The mean (± SD) percentage of affected lung was significantly higher with the high inoculum (31.8 ± 14.6%) than with the low inoculum (14.4 ± 11.4%). Fourteen of 25 foals developed uveitis and 20 of 28 foals developed polysynovitis. R. equi was cultured from the aqueous humor of 11 foals and from the synovial fluid of 14 foals. The risk of development of polysynovitis and protein concentration in the aqueous humor were significantly higher in foals that received the high inoculum. These results indicate that polysynovitis and uveitis are septic complications associated with the severity of lung disease
- …