ABSTRACT
Objective To explore the bacteria relevance between index fingers and contactant' surfaces (mobile phone touch screen and desktop of personal office table). Methods Bacteria were collected from the index fingers, mobile phone touch screen and desktop of personal office table of 10 volunteers. Enterobacterial repetitive intergenic consensus(ERIC)-PCR fingerprint was established by PCR amplifi-cation technique of metagenome. Results There were 7 volunteers' ERIC-PCR fingerprints of index fin-gers matched that took from the mobile phone touch screens, and different from each other. There were 3 volunteers' ERIC-PCR fingerprints of index fingers matched that took from desk top of personal office table, and other 7 volunteers' ERIC-PCR fingerprints did not match perfectly with that took from desk top of personal office table,but had at least one similar band for both. Conclusion The bacteria on index finger shows individual specificity, which on mobile phone touching screen and personal desktop may be a new biological sample of forensic identification.
ABSTRACT
BACKGROUND: Bone mineral density is the most important indicator for bone level. Osteoporosis is a worldwide problem, and there is no safe and effective radical treatment. It can only be prevented, so bone mineral density arise more attention. OBJECTIVE: To explore the relationship between skeletal muscle content, physical activity level and bone mineral density in older adults, so as to provide theoretical basis for preventing osteoporosis treatment. METHODS: Totally 111 subjects aged 40 to 84 years were recruited randomly. The bone mineral density was measured by double energy X-Ray bone density meter, and the human skeletal muscle content, fat content and percentage of skeletal muscle were measured by human body component analyzer. The variance analysis was used for multiple group comparisons in different age groups, LSD method for comparisons between groups, and Pearson correlation analysis for correlation analysis. RESULTS AND CONCLUSION: Bone mineral density was significantly related to the physical activity, body mass, and skeletal muscle content (r=0.30, 0.41, and 0.45, P ＜ 0.01). For middle and older adults, skeletal muscle content, physical activity level and body mass were positively related to bone mineral density. Age and bone mineral density had a negative relationship. These results indicate that physical activity is an important factor affecting bone density, and higher level of physical activity is beneficial to maintain and improve bone mineral density. Increasing muscle mass and improving body composition can improve bone mineral density.
ABSTRACT
BACKGROUND: Skeletal muscle system is the driving force to reveal the change of human body movement, and its modeling is the key technology of human body modeling. OBJECTIVE: To establish models of skeletal muscle of human lower limb based on UG and ADAMS. METHODS: Body size parameters of the lower limbs of six men were measured. According to the collected motion parameters of the lower limbs, ground reaction force (ground support) and electromyogram signal of lower limb muscle group, ADAMS with the dynamics and kinematics simulation was conducted to get simulation parameters, such as ground reaction force, joint force, and link point displacement. Simulation value was compared with the measured value. Finally, MATLAB was used for simulation analysis. RESULTS AND CONCLUSION: It is concluded that the measured ground reaction force, joint angles, and link point displacement had very significant linear correlation with ADAMS simulation data. The simulation results show that a model of human lower limb skeletal muscle established by UG and ADAMS can effectively solve the tedious multi-rigid-body dynamics problems through the simulation calculation.