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Biomedical subjects

J L Saunders

Publications and source records attributed to J L Saunders.

9 recordsLinked to original sources

Estimating economic thresholds for pest control: an alternative procedure.

An alternative methodology to determine profit maximizing economic thresholds is developed and illustrated. An optimization problem based on the main biological and economic relations involved in determining a profit maximizing economic threshold is first advanced. From it, a more manageable model of 2 nonsimultaneous reduced-from equations is derived, which represents a simpler but conceptually and statistically sound alternative. The model recognizes that yields and pest control costs are a function of the economic threshold used. Higher (less strict) economic thresholds can result in lower yields and, therefore, a lower gross income from the sale of the product, but could also be less costly to maintain. The highest possible profits will be obtained by using the economic threshold that results in a maximum difference between gross income and pest control cost functions.

Animals↗

A program evaluation of classroom data collection with bar codes.

A technology incorporating bar code symbols and hand-held optical scanners was evaluated for its utility for routine data collection in a special education classroom. A different bar code symbol was created for each Individualized Educational Plan objective, each type of response occurrence, and each student in the first author's classroom. These symbols were organized by activity and printed as data sheets. The teacher and paraprofessionals scanned relevant codes with scanners when the students emitted targeted behaviors. The codes, dates, and approximate times of the scans were retained in the scanner's electronic memory until they could be transferred by communication software to a computer file. The data from the computer file were organized weekly into a printed report of student performance using a program written with commercially available database software. Advantages, disadvantages, and costs of using the system are discussed.

Child↗

Relevance of the popliteal angle to hamstring length in cerebral palsy crouch gait.

The popliteal angle is a widely used clinical means of assessing hamstring length in cerebral palsy patients. The relevance of the popliteal angle as a measure of hamstring length was assessed in this prospective study. Sixteen patients with cerebral palsy with crouch gait had their conventional and modified popliteal angles measured by nine observers on two separate occasions. With use of the conventional and modified forms of the test, 74 and 70%, respectively, of the observed variability was inter-and intraobserver related. The range of SDs for each observer using the conventional test was 7.1-13.6 degrees (average 10.9 degrees ), and with use of the modified form of the test, the range was 6.3-4.2 degrees (average 10.5 degrees ). The maximum hamstring length of each subject during gait was determined by three-dimensional modelling of their lower limbs. The modified popliteal angle measurements of the most repeatable observer demonstrated an inverse relationship between modified popliteal angle and maximum hamstring length (p < 0.01) and muscle excursion (p < 0.01). Only 10 of 32 limbs had short medial hamstrings.

Adolescent↗