[Progress in isokinetic technology in testing and training for assessment of muscle function].

Isokinetic technology in testing and training is the most advanced practical technique in the evaluation of muscle function. This method is a continuous dynamic test in the full range of the joint motion which has strong pertinence at the aspect of assessing muscle strength, and is an objective and quantitative method for reflecting each point's muscle strength in the range of the joint motion. This article reviews the key concepts, brief history of development and influencing factors of isokinetic technology in testing and training, introduces the progress in the field of rehabilitation medicine and sport science, etc., and discusses the future exploration in forensic science.

[Application of Demirjian's method for chronological age estimation in teenagers of Shanghai Han population].

OBJECTIVE: To study the applicability of Demirjian's method for age estimation in teenagers of Shanghai Han population in China. METHODS: Paired t-test was performed between the chronological age and the age determined by Demirjian's method of 501 teenagers whose orthopantomograms were collected from the ninth hospital of Shanghai. There were 168 boys and 333 girls involved in this study with chronological age from 11 to 20 years. Uni-factor model was used to explore the relationships of the two kinds of age. RESULTS: For the marked difference between the chronological age and determined age, Demirjian's method was not suitable to the Chinese Han adolescents. The results of paired t-test between chronological age and predicted age from quadratic equation showed that there was no significant difference in boys aged 12-16 years, in girls aged 12-14 years and 15-17 years repectively. The uni-factor model could make the error of determined age less than 1 year to 81.04% of the samples. CONCLUSION: The age between 11 and 17 years can be well estimated by our method, except for the 17 years of age and above.

[Age estimation by dental radiological imaging].

Dental age plays an important role in age estimation. It has often been used together with skeletal age to improve the accuracy of age estimation abroad, but seldom performed in China. As a noninvasive technology, dental radiological imaging has been widely used in age estimation. By observing the age-related changes such as the pulp cavity and development of crown and root on radiographs. Gleiser and Hunt, as well as Demirjian have developed different methods to determine the age of human. Demirjian's method has been proved to be more accurate but with limitation when used in persons of eighteen and above. The accuracy and reliability of the measurements on pulp cavity could be improved as the development of computed tomography with its high resolution and intelligent software. As a convenient and accurate method, age estimation from dental computed tomographs would be more promising in the future for forensic scientists and anthropologists.

Preparation and theophylline delivery applications of novel PMAA/MWCNT-COOH nanohybrid hydrogels.

A series of nanohybrid hydrogels was designed and developed based on a hydrogen bond self-assembly of poly(methacrylic acid) (PMAA) networks and carboxyl-functionalized multi-walled carbon nanotubes (MWCNT-COOH). The nanohybrid hydrogels show low micropore densities and large mesh sizes with an increase in MWCNT-COOH content. Particularly, the hydrogels containing 10 wt% MWCNT-COOH was observed to collapse at pore walls because of large holes, which is believed to be responsible for high swelling. The ability of the MWCNT-COOH to self-associate with PMAA or water molecules via hydrogen-bonding interactions and an additional electrostatic repulsion govern both pH response of the network and drug release. Increasing pH values causes equilibrium swelling ratios and accumulative release to be elevated. On the other hand, modified mechanical behavior can be obtained under a low content of the MWCNT-COOH in that the high MWCNT-COOH filling effects the formation of PMAA gel networks. Swelling and controlled release profiles of theophylline could be modulated by changing pH values, introducing the MWCNT-COOH and adjusting the proportions of the MWCNT-COOH component.