Urine dipstick analysis for identification of runners susceptible to acute kidney injury following an ultramarathon

Abstract

This study examined whether urine dipstick testing might be useful to predict the development of acute kidney injury after an ultramarathon. Participants in the 2011 161-km Western States Endurance Run underwent post-race blood and urine dipstick analyses. Of the 310 race finishers, post-race urine dipstick testing was completed on 152 (49%) and post-race blood also was obtained from 150 of those runners. Based on “injury” and “risk” criteria for acute kidney injury of blood creatinine 2.0 and 1.5 times estimated baseline, respectively, 4% met the criteria for injury and an additional 29–30% met the criteria for risk of injury. Those meeting the injury criteria had higher creatine kinase concentrations (P < 0.001) than those not meeting the criteria. Urine dipstick tests that read positive for at least 1+ protein, 3+ blood, and specific gravity ≥ 1.025 predicted those meeting the injury criteria with sensitivity of 1.00 (95% confidence interval [CI] 0.54–1.00), specificity of 0.76 (95% CI 0.69–0.83), positive predictive value of 0.15 (95% CI 0.06–0.30), negative predictive value of 1.00 (95% CI 0.97–1.00), and likelihood ratio for a positive test of 4.2. We conclude that urine dipstick testing was successfully able to identify those individuals meeting injury criteria for acute kidney injury with excellent sensitivity and specificity.     

Serial properties of behavior and their chemical modification

Certain features of operant behavior that are sensitive to the adverse effects of chemical exposure can be obscured by exclusive experimental reliance on global measures such as response rate. Temporal patterning of behavior is the clearest example. Reinforcement schedules studied in behavioral pharmacology and toxicology reveal novel consequences of chemical treatment when subjected to analyses of their temporal and serial properties. Fixed-ratio performance, for example, undergoes not only changes in response rate, but also displays distinctive shifts in inter-response time patterning, changes in the interresponse time distribution, and deterioration in what might be termed the cohesiveness of the ratio. Variable-interval performance also may change in distinctive ways that produce altered response patterning without marked changes in rate. Sequential dependencies, as measured by techniques of time series analysis, may also reveal effects not reflected by response rates. Spaced responding and autoregressive schedules provide examples. The serial and temporal properties alluded to above can be described and analyzed by a variety of quantitative techniques that also yield information of theoretical interest.     

Privacy threat model for data portability in social network applications

The advent of the participatory Web and social network applications has changed our communication behaviour and the way we express ourselves on the Web. Social network application providers benefit from the increasing amount of personally identifiable information willingly displayed on their sites but, at the same time, risks of data misuse threaten the information privacy of individual users as well as the providers’ business model. From recent research, this paper reports the major requirements for developing privacy-preserving social network applications and proposes a privacy threat model that can be used to enhance the information privacy in data or social network portability initiatives by determining the issues at stake related to the processing of personally identifiable information.     

Human Performance Technology and Knowledge Management: A Case Study

ABSTRACT As organizations respond to competitive environments and strive to enhance performance, knowledge management (KM) has increasingly become a strategic activity. A KM strategy entails consciously helping people share and put knowledge into action. A key challenge is how to develop and implement KM solutions that provide performance support to knowledge workers and seamlessly integrate KM into business processes. We propose that human performance technology (HPT) provides a systematic framework to help guide KM initiatives. Specifically, HPT provides a holistic view of a knowledge worker's performance environment by considering the complex interdependencies between the organizational context, business processes, and individual performers. Via a case study, we describe and illustrate how HPT guided one organization in its journey to identify the content and structure to best support performance and manage knowledge in a core business process. Based on the case study, we offer lessons for other firms on how HPT can be used to guide KM initiatives.     

Preschoolers at risk: Social,emotional and cognitive considerations

This report examines the IQs of 75 preschool children perceived to be “at risk” by parents, nursery school teachers, and diagnostic nursery staff. Full Scale, verbal and Performance IQs of the WPPSI were correlated with: (a) assessment of problem area (b) socioeconomic and familial variables (c) gross assessments of speech and motor development and (d) attendance, participation and improvement in a special preschool program. Significant correlations were obtained between IQ and: (a) socioeconomic and familial variables, and (b) perceived improvement. The findings emphasize that social, emotional and cognitive factors are interrelated components in the child's global development.     

Teachers’ perspectives on “authentic mathematics” and the two-column proof form

We investigate experienced high school geometry teachers’ perspectives on “authentic mathematics” and the much-criticized two-column proof form. A videotaped episode was shown to 26 teachers gathered in five focus groups. In the episode, a teacher allows a student doing a proof to assume a statement is true without immediately justifying it, provided he return to complete the argument later. Prompted by this episode, the teachers in our focus groups revealed two apparently contradictory dispositions regarding the use of the two-column proof form in the classroom. For some, the two-column form is understood to prohibit a move like that shown in the video. But for others, the form is seen as a resource enabling such a move. These contradictory responses are warranted in competing but complementary notions, grounded on the corpus of teacher responses, that teachers hold about the nature of authentic mathematical activity when proving.

Perceptions of School and Aspirations of Rural Students with Learning Disabilities and Their Nondisabled Peers

This study examined the school perceptions and educational aspirations of 6,599 rural high school students, a sample that included 428 students with learning disabilities (LD). Regardless of disability status, rural high school students who had negative perceptions of school had less well‐defined postsecondary educational plans and less often aspired to complete college or pursue an advanced degree. Compared to nondisabled youth, rural students with LD were more likely to have negative perceptions of school and lower postsecondary aspirations. However, students with LD who had positive perceptions of school more often planned to pursue postsecondary education and aspired to complete college or an advanced degree. Implications for research and interventions pertaining to the educational attainment of students with LD are discussed.