Objective To analyze and compare the changes in local functional activity of the brain under different recovery times after a 90-day,-6° head down bed rest(HDBR)experiment,clarify the mechanism of brain function remodeling during gravity adaptation,and provide imaging basis and guidance for the model construction and health assessment.Methods 36 healthy male volunteers underwent resting-state functional magnetic resonance imaging(rs-fMRI)scans before HDBR(PRE),3 days after 90-day HDBR(R+3),and 26-28 days after 90-day HDBR(R+26-28),and calculated regional homogeneity(ReHo)and low-frequency amplitude(ALFF)and perform statistical analysis between different time points.Results Compared with PRE-status,ReHo value in the left inferior parietal gyrus and ALFF value in the right posterior cingulate gyrus decreased significantly in R+3 status,while ReHo value in the left calcarine,right lingual gyrus and ALFF value in the precuneus,left paracentral lobule,and right postcentral gyrus increased significantly.At R+26-28 status,more brain areas showed significant changes.Conclusion 90 days of long-term HDBR and subsequent recovery will lead to changes in the neural functional activities of the brain's default network,sensorimotor network and visual network,and obvious adaptive remodeling will occur after a longer period of gravity re-adaptation and recovery.

Aging is a major risk factor for diseases such as osteoarthritis (OA) and osteoporosis. However, they are not necessarily the results of aging, and the relationship between changes in bone and cartilage associated with aging and disease progression is still unclear. Studies have shown that the development and progression of OA is not a simple cartilage wear process, while its occurrence involves complex biological, chemical and mechanical changes in the tissues of the entire joint, especially the interaction of mechanics and biochemistry between cartilage and subchondral bone. Aging contributes to the occurrence and development of OA, but it is not the cause of OA. Changes associated with aging provide a foundation for OA to start, making joints more susceptible to other factors such as abnormal biomechanics and biochemistry, thereby promoting the development of OA. Therefore, understanding the basic mechanisms by which aging affects joint tissue may provide new targets for slowing or preventing the development of OA. In this paper, the related research progresses are reviewed from three aspects, i.e. age-related changes in cartilage and subchondral bone, mechanical conduction and angiogenesis.

This paper proposed a mobile vital-signs monitoring system based on ZigBee localization and wireless transmission technology for the elderly in nursing home. The system can monitor the vital-signs (pulse, ECG and blood oxygen), localize human body and warn in emergency. The validity and accuracy of this system were testified by the experiments of mobile acquisition and storage of pulse. In these experiments, the measurement of pulse ranged from 50 to 170 time a minute, the mean error of which was less than 3%. The mean error of localizing was less than 4 m. And the data transmission rate was 250 kbps. The system, which effectively conducts the real-time monitoring of the health and safety situation for the elderly, has a great significance for protecting the elderly's life safety.
Aged ; Equipment Design ; Homes for the Aged ; Humans ; Monitoring, Physiologic ; instrumentation ; Nursing Homes

This paper proposed a mobile vital-signs monitoring system based on ZigBee localization and wireless transmission technology for the elderly in nursing home. The system can monitor the vital-signs (pulse, ECG and blood oxygen), localize human body and warn in emergency. The validity and accuracy of this system were testified by the experiments of mobile acquisition and storage of pulse. In these experiments, the measurement of pulse ranged from 50 to 170 time a minute, the mean error of which was less than 3%. The mean error of localizing was less than 4 m. And the data transmission rate was 250 kbps. The system, which effectively conducts the real-time monitoring of the health and safety situation for the elderly, has a great significance for protecting the elderly's life safety.