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Abstract: Mechanical ventilation systems in residences usually serve a single purpose, providing only a relatively small benefit compared to the capital cost. Polluted areas use mechanical ventilation to filter incoming air, cold regions use it to be able to recover the heat from the stale air going out. However, both issues – energy and air-quality – can be beneficially addressed together using one ventilation system in cold climate regions with air pollution problems, such as Fairbanks, Alaska. This paper presents a dynamic model for evaluating indoor PM2.5 levels and energy consumption associated with ventilation. The model was verified by comparing the model-predicted real-time indoor PM2.5 level with the actual level measured in a Fairbanks home and a good agreement (r =0.95) was found. Then, the model was used to study three ventilation scenarios of a typical home in Fairbanks—natural ventilation, using an HRV, and using an HRV with an additional particulate filter. The external cost associated with breathing the indoor PM2.5 was also evaluated. The scenario with an HRV and an additional filter was shown to have about $380 lower annual energy cost than the scenario with natural ventilation and the saving in the PM2.5 associated external cost was about $690 annually. The savings were shown to exceed the operational costs of the ventilation system. [Copyright &y& Elsevier]

To better understand bird response to percentage and pattern of woody cover in agricultural areas, we recorded richness and abundance of breeding birds in 500-m transects along 18 wooded streams in southeastern Nebraska. Transects had differing amounts of woody cover in the surrounding landscape (∼2-39%) out to distances of 500, 1,000, and 2,000 m. We grouped bird species as woodland (22 species) or edge (30 species) and analyzed results from the 1999 and 2000 breeding seasons using information theoretic methods. Richness of the woodland group increased with percentage of woody cover out to 500 m, but abundance did not change. In contrast, richness of the edge group was not affected by landscape variables, but abundance increased as percentage of woody cover decreased out to 1,000 m. Eight species increased in abundance and 5 decreased with increasing percentage of woody cover in the landscape out to distances of 500, 1,000, or 2,000 m. The great crested flycatcher (Myiarchus crinitus) was not present at sites with ≤14.7% woody cover in the surrounding landscape out to 500 m, and the eastern wood-pewee (Contopus virens), except for one site, was not present at sites with ≤24% woody cover out to 500 m. The Baltimore oriole (Icterus galbula) and warbling vireo (Vireo gilvus) apparently responded to the presence of large eastern cottonwood (Populus deltoides) trees. Management for a diverse avifauna in fragmented agricultural landscapes should include both local- and landscape-scale variables, including the amount and pattern of woody cover in the surrounding landscape. [ABSTRACT FROM AUTHOR]

Interior Alaska has indoor air quality issues similar to those of other far northern communities associated with long cold winters and reduced ventilation rates. Moreover, geological features in the hills around Fairbanks, Alaska increase the likelihood of elevated radon levels. To better quantify these features, our team has gathered data at 68 homes. We used CO[sub 2] concentrations as a surrogate for indoor air quality as well as to help determine ventilation rates to be used in subsequent modeling work. We found the CO[sub 2] data correlated well using basic mass conservation considerations for yearly averages. The summer CO values ranged from 1 to 9 ppm and the winter values from 0 to 23 ppm. For homes with woodstoves, we found the indoor PM[sub 10] concentrations rose after the stoves were fired up. Here PM[sub 10] refers to particles smaller than 10 μm. Over 40% of the tested homes in the hills around Fairbanks had radon levels>4 pCi/L compared to a nationwide average of 7%. Active subslab depressurization systems tested were very effective in reducing indoor radon concentrations (average reduction of over 90% for eight homes). [ABSTRACT FROM AUTHOR]

Presents information on a study which evaluated bird use of rural and urban converted railroad rights-of-way in southeast Nebraska. Survey of birds from 1992 to 1994; Methodology of the study; Results and discussion; Conclusions.

Background: Clinical decision support systems (CDSS) are important tools to improve health care outcomes and reduce preventable medical adverse events. However, the effectiveness and success of CDSS depend on their implementation context and usability in complex health care settings. As a result, usability design and validation, especially in real world clinical settings, are crucial aspects of successful CDSS implementations. Objective: Our objective was to develop a novel CDSS to help frontline nurses better manage critical symptom changes in hospitalized patients, hence reducing preventable failure to rescue cases. A robust user interface and implementation strategy that fit into existing workflows was key for the success of the CDSS. Methods: Guided by a formal usability evaluation framework, UFuRT (user, function, representation, and task analysis), we developed a high-level specification of the product that captures key usability requirements and is flexible to implement. We interviewed users of the proposed CDSS to identify requirements, listed functions, and operations the system must perform. We then designed visual and workflow representations of the product to perform the operations. The user interface and workflow design were evaluated via heuristic and end user performance evaluation. The heuristic evaluation was done after the first prototype, and its results were incorporated into the product before the end user evaluation was conducted. First, we recruited 4 evaluators with strong domain expertise to study the initial prototype. Heuristic violations were coded and rated for severity. Second, after development of the system, we assembled a panel of nurses, consisting of 3 licensed vocational nurses and 7 registered nurses, to evaluate the user interface and workflow via simulated use cases. We recorded whether each session was successfully completed and its completion time. Each nurse was asked to use the National Aeronautics and Space Administration (NASA) Task Load Index to self-evaluate the amount of cognitive and physical burden associated with using the device. Results: A total of 83 heuristic violations were identified in the studies. The distribution of the heuristic violations and their average severity are reported. The nurse evaluators successfully completed all 30 sessions of the performance evaluations. All nurses were able to use the device after a single training session. On average, the nurses took 111 seconds (SD 30 seconds) to complete the simulated task. The NASA Task Load Index results indicated that the work overhead on the nurses was low. In fact, most of the burden measures were consistent with zero. The only potentially significant burden was temporal demand, which was consistent with the primary use case of the tool. Conclusions: The evaluation has shown that our design was functional and met the requirements demanded by the nurses' tight schedules and heavy workloads. The user interface embedded in the tool provided compelling utility to the nurse with minimal distraction. [ABSTRACT FROM AUTHOR]