RESUMEN
For reducing a risk of pressure sore caused by long period sitting on a wheelchair, a patient is required to depressurize buttocks by changing the posture suitably. Thus, we have been developed an automatic depressurization motion assistance system for a seated patient on a wheelchair. In our previous work, we developed a sitting surface coordination system which can lift or incline and assists a depressurization motion of a patient. However, in some cases, it is difficult to change his posture suitably for patients who do not have enough physical strength in their upper body using our proposed device. Therefore, in this paper, we propose a novel posture coordination assistance system for a wheelchair user. Our system consists of the adjustable sitting surface and novel proposed adjustable backrest. These two devices coordinate the sitting posture of the patient automatically. Our key ideas are two topics. One topic is mechanical design of the adjustable backrest for practical use. We realize small mechanism which enables easy implementation to a general wheelchair without special reconstruction. The other topic is a natural posture coordination scheme using the sitting surface and the backrest. We analyze buttocks depressurization operation by a nursing specialist and drive our proposed devices for realizing it. The performance of our system is verified by experiments using our prototype.
Asunto(s)
Postura , Úlcera por Presión/prevención & control , Silla de Ruedas , Anciano de 80 o más Años , Fenómenos Biomecánicos , Diseño de Equipo , Humanos , Proyectos Piloto , Presión , Adulto JovenRESUMEN
Plant-specific Rac/Rop small GTPases function as molecular switches for numerous signal transduction events, including defense responses. To understand the function of each of the seven Rac/Rop family members in rice, we studied the tissue-specific expression patterns of Rac/Rop genes by semi-quantitative reverse transcription-PCR (RT-PCR), and also Rac/Rop subcellular localization using green fluorescent protein (GFP) fusion proteins in transient expression systems. We also investigated the roles of these genes in disease resistance by testing single Rac/Rop-RNAi (RNA interference) plants against the rice blast pathogen Magnaporthe grisea. Our studies show that expression of OsRac2, 6 and 7 is very low in leaf blades, and reveal a strong correlation between the number of lysine and/or arginine (KR) residues in the polybasic region of Rac/Rop GTPases and their subcellular distribution in vivo. Infection assays showed that OsRac1 is a positive regulator of blast resistance, confirming previous observations, whereas OsRac4 and OsRac5 are negative regulators of blast resistance. OsRac6 may make minor contributions to disease resistance, while OsRac3 and OsRac7 are probably not involved in defense. Therefore, our study suggests that the rice Rac/Rop family plays multiple roles in diverse cellular activities and has both positive and negative functions in disease resistance.