PURPOSE: Although the tipping lever of a wheelchair is used to lift up and down the casters, it is not always easy to use probably because the present shape and position of the tipping lever are not appropriate. In the present study, we investigated the relationship between the power needed to lift up and down casters and positions of the tipping lever to find out an appropriate position for the tipping lever.
METHOD: Twelve participants having a certain care skill with a wheelchair participated. By using adapters on the original tipping levers on both sides, the height of the tipping lever and its distance from propulsion wheel axis could be changed from 75 mm to 175 mm and from 110 mm to 230 mm, respectively. The subjective physical load on their upper and lower limbs and lumbar area was measured when they lifted up and down the casters. The weight on the seat of the wheelchair was set at 70% of maximum weight that the participants could lift up.
RESULTS: The size of the physical load on their upper and lower limbs and lumber area decreased linearly as the distance from the axis of propulsion wheel increased. These three body parts showed a similar tendency. The physical load on these body parts decreased when the height of the tipping lever decreased, though the relationship was not linear and varied depending on the distance from the propulsion wheel axis. These effects were almost the same for both lifting up and lifting down of the casters by the participants. By examining the space behind the wheelchair, it was found that the most efficient position in terms of physical load was at 125 mm in height and 225 mm in distance from the axis of propulsion wheel.
CONCLUSION: By elongating and lowering the tipping levers of a wheelchair by certain amounts, to lift up or down the casters becomes easier for helpers with low physical strength.

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Desk sharing in offices has become recently a trend due to the wide spread use of notebook computers. However, they are not always comfortable to use either for reading or typing. We measured the most suitable seating conditions for working with notebook computers. Within the range of heights from the 5th percentile of young females to the 95th percentile of young males, the following optimal conditions were determined. The angles of the keyboard, lower backrest, upper backrest and seat are 10°, 68°, 79° and 10°, respectively. The depth of the middle part is shortened to 354 mm for short user. The depths of both outside sections are lengthened to 378 mm, with inclined lateral supports (maximum angle 35°) for tall user. To allow the display to be comfortably read, the seat height must be 350～410 mm, which is lower than that for conventional office chairs. Evaluations showed that when using this prototype seat in a working environment for 40 minutes, muscle activities in the shoulder and back, and leg swelling were reduced to those when using a conventional office chair, without any decrease in work efficiency. Also, forward tilting of the head decreased by 9° and the shoulder elevation was improved.

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The purpose of this study was to examine medication errors and confirmation behavior of nurses' administering oral medications. The experiment was conducted on 63 nurses at a nursing lab where 16 beds were arranged, and the behavior of nurses was recorded by video camera. The nurses were instructed to give drugs following the prescriptions to the bedside of 6 simulated patients.
As a result, medication errors were observed with 32 nurses (50.8%), and dosage errors were the most frequent type of error. There are two types of confirmation, finger pointing and calling. Analysis of variance (ANOVA) was conducted to compare the numbers of medication errors among three groups, i.e. both confirmation group, either confirmation group, and neither confirmation group. Main effect of confirmation was significant during the preparation stage. Nurses who did one or both of the two types of confirmations made fewer errors than those who did neither. Main effect of confirmation was significant during the administration stage. Nurses who did both of the two types of confirmations made few errors than those who did one or neither.

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In this paper, development of a gait training robot for effective acquisition of cane walking is presented. The cane-shaped robot has a movable platform and supporting member for cane walking. By installing an omnidirectional mechanism in the robot, it can move in any direction. It consists of two components: training and assistance. In the training component, the robot projects images onto the floor. The image shows a target leg position of a cane walker. The robot evaluates the gait and gives feedback to the user. In the assistance component, the robot keeps the user's posture for safety. The robot outputs sounds that can provide motivation and rhythm for training. The purposes of this system are enjoyable training for users and worksaving for rehabilitation staff.

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