Measuring upper limb movement to analyze intra-body communication channel attenuation characteristics.

BACKGROUND: This experiment was designed to study the respective effects of the closed-state human palm and dynamic arm bending on intra-body communication channel attenuation. METHODS: We selected the right upper arm of a healthy adult male as the experimental object to measure channel attenuation variation in a closed or open palm, and when the arm was bent, so as to analyze channel characteristics. CONCLUSIONS: The experiment showed that, in a quasi-static stable system, the effects of a closed palm on channel attenuation were negligibly minimal. In contrast, the physiological signal of the living body significantly interfered with the channel in the low-frequency mode. In the dynamic arm-bending experiment, we found that the attenuation variation range corresponds to the intersection angle (90∘⩽θ⩽ 180∘) of the upper arm and forearm; these results provide the basis for the establishment of a theoretical model.

Proteomic investigation of resistance to chemotherapy drugs in osteosarcoma.

BACKGROUND: Osteosarcoma, which is also termed osteogenic sarcoma or osteoma sarcomatosum, is the most common form of bone cancer. Typical osteosarcoma can occur at any age, including in infants, children, and the elderly, but more than half of cases occur in individuals who are 10-20 years old. OBJECTIVE: Here, the objective was to search for protein markers to indicate resistance to cisplatin in osteosarcoma and provide a theoretical basis for the early and accurate use of cisplatin to treat osteosarcoma. METHODS: Thirty patients with osteosarcoma were selected for the study. Experimental studies on the chemosensitivity of osteosarcoma using an in vitro kit method were performed, and cisplatin-resistant and cisplatin-sensitive osteosarcoma tissues were obtained. A representative sample was chosen to analyze and identify differentially expressed proteins in cisplatin-resistant tissues. RESULTS: The osteosarcoma-sensitive tissue was analyzed using 2-D electrophoresis and time-of-flight mass spectrometry. Differently expressed proteins were analyzed by western blotting to identify markers. Cisplatin-resistant and cisplatin-sensitive osteosarcoma tissues were obtained. Five significantly differentially expressed proteins were identified, including ALDOA and PGK1. CONCLUSIONS: The results indicate that ALDOA and PGK1 might be appropriate markers that can be used when treating osteosarcoma with cisplatin.

Modeling of sectionally continuous communication channel with inhomogeneously distributed tissues.

BACKGROUND: This study aimed to investigate effects on the transmission channel caused by heterogeneous distribution in tissues and joint characteristics. METHOD: Human arm section scans were taken using CT technology, and zoned, following which, a circumference measurement experiment was performed to analyze the effect of inhomogeneous distribution of tissues. In order to analyze the arm joint's effect on channel transmission, we proposed a piecewise modeling method in combination with connection conditions. CONCLUSIONS: It can be seen from the experiment that, in the quasi-static mode, the communication channel error caused by the inhomogeneous distribution of tissues is small enough to be negligible. The error between calculated and experimental results is reduced by 3.93 dB in this experiment relative to models that did not include joint characteristics, and the average error is lowered by 0.73 dB. The variation curve fit to experimental data is also improved in this method. As such, it can be quantitatively determined that a channel model with joint characteristics is superior to models excluding joint characteristics.

A numerical model for blast injury of human thorax based on digitized visible human.

Knowledge of the pressure distribution around human thorax in blast help to understand the injury mechanisms and their assessment. To investigate the transmission mechanism of the pressure on human thorax in blast, a three dimension surface model of human thorax was constructed in this work. To increase the precious of this model, tetrahedron element division method was applied to transfer the rough 3D surface model to hexahedral elements model. Using this model, the high pressure duration was computationally solved using numerical simulation of the hexahedral elements. Simulation results showed that the apex of lungs was subjected to the largest stress in a blast. In order to verify this result, an animal experiment was performed on a dog. The animal experimental results was shown to have a same variation tendency with the calculation results based on our numerical model of human thorax, which made this model reliable for the blast injury research.