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This paper reports validity evidence for the use of sensor-based skill measures in evaluating performance differences in rifle marksmanship. Nagashima, Chung, Espinosa, Berka, and Baker (2009) describe four measures used to predict skill classification of expert and novice shooters for known distance rifle marksmanship, three related to breath control and one for trigger control. In this study, skill measures from seven experts and nine novices were collected and classifications were generated resulting in an overall percent correct of 75.6%, with a sensitivity of 54.3%, and 92.0% specificity.

We propose that future rifle marksmanship research be framed within a phases-of-skill-development model (Ackerman, 1987, 1992; Anderson, 1982; Fitts & Posner, 1967). Prior research on predicting shooting performance suggests a deceptively complex task sensitive to variations in the individual, equipment, and environment. We argue that rifle marksmanship research should be framed around perceptual-motor, cognitive, affective, equipment, and environmental variables. Although it is unlikely that equipment and environment can be controlled, much can be learned—with training implications—about how perceptual-motor, cognitive, and affective variables relate to shooting performance. The phases-of-skill-development model is silent on affective variables but suggests that cognitive factors will be most sensitive to individuals learning how to shoot, and perceptual-motor variables most sensitive to individuals who already know how to shoot. Identification of where trainees are in their skill development could lead to more efficient and targeted training and decreased training costs.

Laser tissue welding is a sutureless method of wound closure that has been used successfully in nerve, skin and arterial anastomoses. An elastin-based biomaterial patch was welded to the intimai surface of porcine aorta in the present study. The aorta was stained with indocyanine green dye to efficiently absorb the 808 nm diode laser light. Laser welding with a pulsed diode laser thermally confines heating to the stained portion of tissue, minimizing adjacent tissue damage. Laser welds of stained aorta to biomaterial were attempted by sandwiching the samples between glass slides and applying pressures ranging from 4 to 20 N cm-2for 5 ms pulse durations and 83 mJ mm-2radiant exposure. Bleaching of the indocyanine green by as much as 85% was observed after exposure laser irradiation. Finally, successful welds required 5 N cm-2of pressure between the elastin biomaterial and aorta.

Intravascular ultrasound imaging catheters and forward firing laser atherectomy systems are both being used in the coronary vascular tree of man. When used in conjunction, ultrasound imaging may reduce the probability of perforation and dissection related to laser atherectomy. A novel system is presented which combines ultrasound imaging and laser atherectomy capabilities on the same catheter. The system incorporates a holmium YAG laser directed perpendicular to the long axis of the catheter along with a co-directional ultrasound sensor. Ultrasound images are assembled by computer using the angle of the catheter tip and its linear advance associated with each ultrasound echo signal.In vivo experimental results are presented.

An agar plate test is described to determine the growth inhibition of dermatophytes by fungicides applied to fabrics. Trichophyton rubrum and Epidermophyton floccosum, two major causative agents of tinea pedis (athlete's foot), were used as test organisms. The assay was capable of distinguishing between direct contact effects and diffusion of fungicide into the agar medium, and could be used semi-quantitatively. The method included an essential sterilization stage to prevent interference by micro-organisms contaminating the test materials. Loss of fungicide efficacy due to the sterilization procedure required careful control.