Optimal solutions for complex design problems: Using isoperformance software for human factors trade offs

A major application of isoperformance is as a trade-off methodology of the three major drivers of system design; equipment, training variables, and user characteristics. The flexibility of isoperformance allows each of these three components to be nearly any rational variation. For example, aptitude may be military Armed Forces Qualification Testing (AFQT) categories, cutoff scores within a selection procedure, or simply dichotomizing high and low scorers (pass/fail). Equipment may be new versus old, 'smart' versus dumb, high versus low resolution, etc. Training may be short versus long or varieties of media types (lecture versus CAI/CBI versus self-paced workbooks). In its final computerized form isoperformance lets the user set an operational level of performance (e.g., a jet pilot in a simulated emergency must take prescribed corrective action and clear the plane in several seconds, pilot astronauts will check out all shuttle flight systems within 30 minutes, or Mission Specialists must handle sucdessfully a required number of job elements). At this point the computer program guides the user through any requested trade-offs of the three components while maintaining the specified operational level of performance through isoperformance curves. A demonstration of the computer program is currently available

Regulation of Business - Sales - Below-Cost Statutes - The Elements of Violations and the Defense of Meeting Competition

The purpose of this comment is to discuss two controversial aspects of the sales-below-cost statutes: (1) the intent or effect required for a :finding of violation and (2) the defense of meeting competition

Map Use in Small-Town Planning Documents in Northeast Ohio

Author Institution: Department of Geography and Planning, University of AkronMaps are of fundamental importance to the planning profession. This paper examines the use of maps in planning documents from small towns in northeast Ohio. It considers the frequency of map use, the types of maps utilized, and their quality. Map quality is evaluated by determining the presence or absence of basic map elements and the utilization of a lettering hierarchy for the various map elements. Maps are found in all the plans (median =10) and these represent about one-quarter of non-textual materials. Maps of community facilities and land use are most common, accounting for over half of all maps. Key map elements are included on almost all maps, but few incorporate a lettering hierarchy to reflect the importance of the various elements. The increasing availability of computer mapping programs and the ease with which inadequate maps can be produced make it imperative that planners become more cognizant of the proper techniques for effective cartographic communication. More comprehensive studies are warranted examining the use of maps in planning documents from a wider range of types and sizes of administrative units—i.e., cities, metropolitan areas, and countie

A polymer coated cicaprost-eluting stent increases neointima formation and impairs vessel function in the rabbit iliac artery

Drug-eluting stents have been successful in reducing in-stent restenosis but are not suitable for all lesion types and have been implicated in causing late stent thrombosis due to incomplete regeneration of the endothelial cell layer. In this study we implanted stents coated with cicaprost, a prostacyclin analogue with a long plasma half-life and antiproliferative effects on vascular smooth muscle cells, into the iliac arteries of rabbits. At 28-day follow-up we compared neointima formation within the stented vessels and vascular function in adjacent vessels, to assess if cicaprost could reduce restenosis without impairing vessel function. Arteries implanted with cicaprost eluting stents had significantly more neointima compared to bare metal stents. In adjacent segments of artery, endothelium-dependent relaxation was impaired by the cicaprost-eluting stent but vasodilation to an endothelium-independent vasodilator was maintained. We conclude that the presence of the polymer and sub-optimal release of cicaprost from the stent may be responsible for the increased neointma and impaired functional recovery of the endothelium observed. Further experiments should be aimed at optimising release of cicaprost and exploring different stent polymer coatings

Coccidiomycosis infection of the patella mimicking a neoplasm - two case reports.

BackgroundCoccidioidomycosis is an endemic fungal infection in the southwestern of United States. Most infections are asymptomatic or manifest with mild respiratory complaints. Rare cases may cause extrapulmonary or disseminated disease. We report two cases of knee involvement that presented as isolated lytic lesions of the patella mimicking neoplasms.Case presentationThe first case, a 27 year-old immunocompetent male had progressive left anterior knee pain for four months. The second case was a 78 year-old male had left anterior knee pain for three months. Both of them had visited general physicians without conclusive diagnosis. A low attenuation lytic lesion in the patella was demonstrated on their image studies, and the initial radiologist's interpretation was suggestive of a primary bony neoplasm. The patients were referred for orthopaedic oncology consultation. The first case had a past episode of pulmonary coccioidomycosis 2 years prior, while the second case had no previous coccioidal infection history but lived in an endemic area, the central valley of California. Surgical biopsy was performed in both cases due to diagnostic uncertainty. Final pathologic examination revealed large thick walled spherules filled with endospores establishing the final diagnosis of extrapulmonary coccidioidomycosis.ConclusionsThough history and laboratory findings are supportive, definitive diagnosis still depends on growth in culture or endospores identified on histology. We suggest that orthopaedic surgeons and radiologists keep in mind that chronic fungal infections can mimic osseous neoplasm by imaging

Preparation and Stability of Diphenyl Amine Hydronitrate

In connection with certain proposed studies the question of the preparation of diphenyl amine hydronitrate, or diphenyl ammonium nitrate, arose. A search of the literature revealed no record of this substance. The nearest equivalent reported was the perchlorate salt of diphenyl amine (Ber. 43, 1085-86. 1910). This compound was obtained upon treatment of a carbon tetrachloride solution of the amine with 70% perchloric acid added dropwise

Process for synthesizing enediynes

A process for synthesizing enediynes is provided. Specifically, the formed enediynes contain a hex-3-ene-1,5-diynyl group. Production of the enediynes involves adding a base to a propargylic halide in the presence of a chelating agent, which causes a carbenoid coupling-elimination sequence of the propargylic halides. A carbenoid destabilizing agent can also be added to the reaction mixture in order to enhance yield. Acyclic and cyclic enediynes can be synthesized according to this process. The enediynes are useful compounds that can be used in a variety of applications including use in the production of anti-tumor agents