The Japanese Red Cross Society is using nucleic acid amplification testing (NAT) to secure the microbiological safety of blood products. The serum has individual difference because the blood is collected from many humans located in various parts of the country. The association reported that the results of NAT were influenced by slight differences in blood components. We designed a viral detection method consisting of a metal-coated hollow fiber (MCHF)-membrane and loop-mediated isothermal amplification (LAMP). This detection method was highly sensitive and much quicker than NAT. In this study, we used two kinds of simulated serum samples that used the bovine serums of different lot numbers and reviewed stability for slight differences in blood components in terms of the designed viral detection. We examined the influence of individual differences on only LAMP for bovine serum of different lot numbers as the first step. LAMP couldn't detect the virus in nay of the simulated serum samples. As the next step, we tested the influence of serum individual differences on viral detection consisting of MCHF-membrane and LAMP. As a result, this viral detection method was able to detect herpes simplex virus type 1 from simulated serum samples containing more than 10 PFU/mL of virus without influence from individual differences. MCHF-membrane possesses an isolation function, in which it captures HSV-1 of more than 100 nm in membrane pore size and passes the bovine serum origin protein, etcetera of less than 100 nm in pore size. Therefore, even if simulated serum samples have individual differences, components in the serum are removed. Gene amplification such as LAMP after viral capture and gene isolation using MCHF-membrane in this viral detection method was uninfluenced by serum individual differences. This viral detection method is stable and not influenced by serum individual differences, and is thus an epoch-making method.

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We are investigating the performance of trajectory control when passive motion is given to a region of the human body. Such passive motion given by trajectory control using a robotics device has been applied to motion analysis of the human body. In this paper, we focus on a parallel wire-driven system that utilizes light flexible wires instead of heavy rigid links, which characteristically has many advantages such as safety, structural transparency, large motion area, ease of maintenance and expandability as compared with other systems. Reeling wires by actuators, this system can control the length of wires or tension. In regards to trajectory control, iterative learning control is one of the most useful methods for this case, because the scheme can easily achieve trajectory control with a high degree of accuracy even if system-dynamics is unknown and fluctuate. We deal with the passive motion of a human arm in a vertical plane using the parallel wire-driven mechanism and iterative learning control. The purpose of this study is to evaluate the performance of the trajectory control quantitatively by measuring EMGs and R—R intervals.

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The purpose of this study was to develop a finger-tapping acceleration measurement system for the quantitative diagnosis of Parkinson's disease. The system was composed of 3-axis piezoelectric element accelerometers, touch sensors made of thin stainless steel sheets, an analog-digital (AD) converter and a personal computer (PC). Fingerstalls, with these sensors, were attached to the index finger and thumb. The acceleration and output of the touch sensor were recorded using the PC during the finger-tapping movements. Intervals between the single finger-tapping movements were calculated from the measured output of the touch sensor. Velocities during the single finger-tapping movements were calculated by integrating the measured acceleration. The amplitudes were calculated by integrating the velocities. Forces generated when the fingers contacted were estimated from the acceleration using a filter, G (jω). The standard deviation of the single finger-tapping intervals, average of maximum single finger-tapping velocities, average of maximum single finger-tapping amplitudes and standard deviation of maximum force were calculated from them. They were used as features for the quantitative diagnosis of Parkinson's disease. Preliminary experiments were executed with a normal subject. The results showed that maximum single finger-tapping velocity, maximum single finger-tapping amplitude and maximum force could be measured fairly accurately when single finger-tapping movement interval times were less than 0.4 s. The system developed was used to conduct finger-tapping tests employing 27 normal subjects and 16 Parkinson's diseases subjects. The subjects executed continuous finger-tapping movement for 60 s. It was shown that the acceleration and output of the touch sensor could be measured and the features could be extracted.

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To assure security and reliability for medical services under the conditions of limited financial and human-resources, it is important to develop a quantitative method for adequate scheduling of each medical task provided by medical staff. In this paper, we developed a task classification system for medical staff from the view-point of job scheduling and applied it to actual clinical nursing time-motion study data. Based on the interview data from the three trained nurses working in a surgical ward, four scheduling points were drawn by ethnomethodological word mining ; [indispensability], [expectation], [laborforce for operation], and [time dependency]. The time-motion study data of one nurse working in a surgical ward during the daytime was analyzed from this point of view ; the nurse was in charge of five patients including one patient scheduled for surgery. The results were : (1) Almost all tasks related to major demand (e.g.,, transfer of patient to the operating room) with high indispensability and expectation, and time dependency ; (2) Required much time to complete the task (e.g., time required to transport the patient to the operating room), or were jobs with low time dependency that were selectively carried out ; (3) Required answering a nurse-call or telephone, which was classified into a task with high time dependency. In the analysis, some jobs were arranged in the order of inefficiency, contrary to the scheduling classification. The classification showed good consistency with the clinical decisions on scheduling nursing services, and the results explained well the way of scheduling nurse's duties.

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This paper presents a real-time three-dimensional imaging system using integral videography (IV) with intra-operative data acquisition that applies three-dimensional (3D) ultrasound to create a minimally invasive cardiac surgery navigation system. We used a trans-vaginal ultrasound probe with a volume data acquisition rate of 5 volumes/s. Coordinate transformation and image enhancing is performed as 3D data preprocessing. An interpolation profile is used to improve the performance of coordinate transformation. We implemented a 3D diffusion stick filter for speckle suppression to enhance image quality. Experiments using a human hand as a phantom showed that the online IV image frame rate is around 2 frames/s. As an attempt to further increase system performance, the use of smart multi-threading for IV rendering completely resolved the problem of performance loss due to non-uniform data distribution. We are considering how to combine the quickness of ultrasound and the image quality of CT for further development.

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We have developed an fMRI-MEG integrative method that is capable of analyzing spatiotemporal multiple cortical activities. Firstly, activated regions were determined by statistically analyzing fMRI data. Secondly, using fMRI analysis results as a spatial constraint, the location and orientation of equivalent current dipoles (ECD) were estimated by a procedure that maximizes the inner product of lead field and measured field vectors. The time-varying dipole moment was obtained by projecting the optimized lead field vector to measured fields. We applied the technique to data obtained during a visual perception task. An apparent motion stimulus that activates both primary and secondary visual areas (V1/2) and V5 was used in the experiment. Event-related neuromagnetic fields were measured by a 306-channel MEG system, whereas the fMRI data were acquired by a 1.5 T MR system. The present fMRI-MEG integrative analysis method successfully detected dynamic cortical activities in V1/2 and V5.

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Many studies have been carried out in order to understand the real effects of space environment on the human body. Our aim is to create a very small, energy-saving vital signs monitoring device capable of facilitating simple and precise blood tests in an orbiting vehicle where harsh technical conditions experienced. The device also has the potential to be used portable and ubiquitous diagnostics systems for medical care at home or bedside. In this study, we developed a micro-fluid device using laser-processing and resin-lamination methods. A number of heat-hardening resin films are layered on a soda glass. A laser is used to fabricate part of the channel on each film for every lamination. The channels are 45 μm in depth and 50-150 μm in width. The components we have currently produced were : 1) a trident channel structure ; 2) a solid-body flow channel with a micro-pipe, both of which were designed to make blood cells flow in a single line in the channel for cell counting ; and 3) a micro-flow channel simulating a capillary vessel for measuring blood coagulation, platelet aggregation, and transformation of red blood cells. We have successfully observed blood cells flowing in these micro-fluid devices.

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The kinematic characteristics of the foot thumb were evaluated in order to develop a new input device; the “Foot Mouse.” Seven healthy subjects pushed a sensor button placed under the right-foot thumb and three components of the pressure were measured by the sensor. The subjects were requested to push the button in five directions applying three kinds of effort each. The maximum value among the lateral, anterior and posterior pressures was about 3.5 kgf and the maximum downward pressure force was about 19.2 kgf. The objective direction of recording pressure was different from the direction of the user's intention. Large downward pressure was observed in every task. Moreover, there were significant variations in kinematic characteristics between individuals. A dedicated transformation process for these objective pressure components should be designed for the interface of the “Foot Mouse.”

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The weight of sliding doors used in residences, especially sliding glass doors, has increased in recent years due to the need to provide thermal insulation, security and design. As a result, it has become important to consider easy of use, especially by elderly people, at the time of product planning. In this context, basic operations characteristics that elderly people show must be figured out first and foremost. As one of example for operability, JIS defines the opening and closing forces, which are equivalent to the maximum static friction force of a door; however, it does not specify the relationship with the weight of a door. A full-size experimental device was developed where the opening and closing forces were controlled independently from the weight of a door. In the experiment, three door weights, 20, 40 and 60 kgf, and two opening and closing forces, 5 and 10 N, were used. The sensory evaluation for opening and closing operations of the sliding door were measured with ten subjects including five elderly males and five elderly females. The force on an operating part applied by subjects when opening and closing the door was also measured in each experiment. The test results clarified basic knowledge for improving the operability of sliding doors : the evaluation score of ease of opening and closing the door decreased and the applied force on the operating part increased as the weight of the door increased, although the opening and closing forces remained the same.

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