Hydroxyapatite particles as a controlled release carrier of protein.

This study examines the possibility of using hydroxyapatite (HAp) particles as a controlled release carrier of protein. In order to achieve effective protein release from HAp particles, it is necessary to regulate the conjugated amount of protein on HAp and the resorption of HAp. HAp particles were synthesized at different temperatures (40 degrees C, 60 degrees C, 80 degrees C) in wet condition and the physico-chemical properties of synthesized HAp particles were examined. HAp particles synthesized at low temperatures showed low crystallinity, high solubility and large specific surface area. The useful growth factors for bone regeneration, such as BMP, bFGF and TGF-beta, are basic proteins, so cytochrome c (pI=10.2) was used as a model protein and the adsorptive property of protein on HAp particles was investigated. The protein adsorption on HAp particles changed depending on its specific surface area and the chart of protein adsorption on HAp particles showed a typical Langmuir curve. These findings suggest that the adsorbed amount of protein on HAp particles could be regulated by HAp synthesizing temperature and the concentrations of protein solution. The release kinetics of protein from the HAp particles that adsorbed the protein (HAp-pro) was also evaluated in different pH solutions (pH 4.0 and 7.0). The released protein gradually increased time dependently when HAp-pro were immersed in pH 4.0 solution, but the released protein was significantly smaller when HAp-pro were immersed in pH 7.0 solution. Moreover, the release rate of protein from HAp-pro differed in each HAp that was synthesized at different temperatures, suggesting that the release of protein from HAp-pro depended on HAp resorption. These results suggest that HAp particles synthesized at different temperature are useful as a controlled release carrier of protein.

Mechanical and magnetic properties of nickel-dispersed tetragonal zirconia nanocomposites.

Effects of Ni dispersions on microstructure and mechanical properties have been studied for Y2O3-stabilized tetragonal zirconia (Y-TZP)/Ni nanocomposites with Ni dispersion up to 10 vol%. Composites were successfully fabricated by reducing and hot-pressing Y-TZP/NiO powder mixtures. Fracture strength was significantly improved from 1.5 GPa for monolithic Y-TZP to 1.9 GPa for nanocomposites with a small addition of Ni (1-2 vol%). Magnetic properties of Y-TZP/Ni nanocomposites were also investigated. Magnetization curves of Y-TZP/Ni nanocomposites showed typical hysteresis loops of soft magnetic materials, whereas coercivity was much larger than that of pure Ni metal. A new function arising from magnetomechanical effects of metallic Ni is also discussed for the present nanocomposites.

Full implementation of a computerized nursing records system at Kochi Medical School Hospital in Japan.

A project to fully implement a novel computerized nursing records system resulted in the standardization of nursing records, reduced the administrative workload for staff, enabled medical staff to know a patient's status at any given time, and improved the quality of nursing care provided to patients. The development process of the computerized nursing records system involved three main steps: 1) the establishment of a new nursing assessment form and introduction of nursing diagnosis into routine work, 2) computerized system design and construction, and 3) the usability check of the computerized nursing records system in a clinical setting for 1 year. The successful development of the computerized nursing records system was based on the following points: 1) the assessment form for nursing diagnosis was improved and the nursing diagnosis was introduced before the computerized system was designed and constructed; 2) full, rather than partial, implementation of the computerized system occurred; 3) existing knowledge of nursing assessments and standard care planning were fully used; 4) registered data were optimally reused upon summarization and readmission to reduce the nurses' workload; and 5) portable computers were introduced to enable simple and quick recording of bedside findings. The routine use of the computerized nursing records system was started in April 2000. More comprehensive investigations during the next 2 to 3 years are necessary to determine how the contents of nursing records can be improved and how much the computerized nursing records system affects the quality of nursing.

Telescience testbed examination aboard Japanese Experiment Module (JEM): life and material science experiments.

A telescience ground testbed experiment was conducted by the National Space Development Agency of Japan (NASDA) at the Tsukuba Space Center in March 1991. The objectives of the ground testbed experiment were to extract scientists' requirements for a communication method, to evaluate the influence of transmission delay and capacity on experiment operations, and to evaluate performance and functions of the system for the testbed experiment. The microscopic operations experiment, the image furnace experiment and the onboard training experiment were selected as typical ground testbed experiments. In these experiments, motion video transmission at 320 kbps was acceptable for observing the experiments and communicating between the principal investigator and the payload specialist. In the microscopic operations experiment, motion video transmission at 1.5 Mbps or more was required for detailed observation. A 4-second transmission delay (roundtrip) was allowable for mutual communication.