Small total dose measurement system for SDS-1

The Japanese Aerospace Exploration Agency (JAXA) uses monitors on board satellites to measure and record in-flight data on ionization effects in space. A compact, total dose measurement system for the small satellite (SDS-1) was developed based on the previous system for measuring total ionizing dose effects. Especially, the sensor for SDS-1 is quite smaller than the sensor for SOHLA-1, which is presented in the last year. The sensor is 8 mm wide×3 mm high×19 mm long and weighs approximately 4 g with 500 mm its wire harness. Eight pin LCC RADFET and temperature sensor are arranged on it. Seven sensors are arranged on some components inside the SDS-1. One of the sensors is arranged on a printed board in advanced microprocessing in-ORBIT experiment equipment (AMI). The AMI demonstrate 320 MIPS microprocessor and DC–DC converter for space. The absorbed dose at the points where the sensors are arranged was evaluated before flight and will be compared with resulting flight data.     

Gravity stress elevates the nociceptive threshold level with immunohistochemical changes in the rat brain.

Young Wistar male rats were exposed to 2G hypergravity by continuous centrifugation for 15 minutes. The nociceptive threshold was measured by using the von Frey type filament on the rat skin surfaces after hypergravity exposure. Following the hypergravity exposure, rats were sacrificed with anesthesia, then perfused and fixed for immunohistochemical examination. The 2G hypergravity elevated the nociceptive threshold up to 2-fold and induced analgesic effects on rats that remained for 2 hours after termination of centrifugation. Expression of Fos-immunoreactive proteins was prominently induced by 2G hypergravity in the arcuate nucleus and the paraventricular nucleus of the hypothalamus. The 15-minute flash exposure to 2G hypergravity induced pain suppression in rats, which might be attributed to change of neuronal activity in rat hypothalamus.