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.

Path Loss Measurement and Channel Modeling with Muscular Tissue Characteristics.

BACKGROUND: The galvanic coupling intra-body communication has low radiation and strong anti-interference ability, so it has many advantages in the wireless communication. METHOD: In order to analyze the effect of muscle tissue's characteristics upon the communication channel, we selected the muscle of pig buttock as the experimental sample, and used it to study the attenuation property with the galvanic coupling intra-body communication channel along the parallel direction and the transverse direction relative to the muscular fibre line as well as on the surface of destroyed muscular fibre; the study frequency ranges from 1kHz to 10MHz.In the isotropic experiment, in order to destroy muscle's fibre characteristics, we grinded the muscle four times, at least five minutes for each time. 0dbm sine-wave signal was input to measure the channel attenuation parameter S21 when the transmitter and the receiver were placed at different positions and different distances d1 and d2 (20mm, 40mm, 60mm), so as to analyze channel loss. CONCLUSION: Within the same frequency range and at the same communication distance, the maximum error of channel attenuation was 10dB; within the same frequency, as the communication distance was increased, the channel attenuation rose gradually, with 4dB increased every 20mm. The conclusion provides the basis for building the theoretical model in the future.

Measurement and analysis of channel attenuation characteristics for an implantable galvanic coupling human-body communication.

In this study, an experiment was designed to verify the low power consumption of galvanic coupling human-body communication. A silver electrode (silver content: 99%) is placed in a pig leg and a sine wave signal with the power of 0 dBm is input. Compared with radio frequency communication and antenna transmission communication, attenuation is reduced by approximately 10 to 15 dB, so channel characteristics are highly improved.

Communication channel modeling of human forearm with muscle fiber tissue characteristics.

Human-Body Communication (HBC) is a wireless communication method using the human body tissue as a transmission medium for signals. This paper on the basis of human muscle fiber tissues' characteristics, it is first proposed to establish the analytical model of galvanic coupling human-body communication channel. In this model, the parallel and the transverse electrical characteristics of muscular tissue are fully considered, and the model accurately presents the transmission mechanism of galvanic coupling human-body communication signals in the channel. At last, through compare with the experimental results and calculation results, the maximum error of the model is 22.4% and the average error is 14.2% within the frequency range.