Innovative accumulative risk assessment strategy of co-exposure of As and Pb in medical earthworms based on in vivo-in vitro correlation.

Recent studies on risks assessment of heavy metal(loid) are usually based on their total concentrations. Nevertheless, such an analysis does not assess their real amounts absorbed by human body. To scientifically assess the health risks, in this study medical earthworms were analyzed for relative bioavailability (RBA) of arsenic (As) and lead (Pb) using a multiple gavage mouse model with liver, kidneys, brain, and leg bones as biomarkers for the first time.

Analysis of longitudinal coupling dynamic characteristics of deep sea mining vessel and stepped lifting pipe.

In deep-sea mining, the coupling dynamic response between the mining vessel and the lifting pipe is a significant problem, which directly affects the structural design of the lifting system and the safety of field operation. The characteristics of coupled motion model have not been fully considered in the existing research. Therefore, this paper uses time-domain coupled numerical model as the research object, considering ocean current, surface wave, pipe dynamics and vessel-pipe contact mechanics, to study the dynamic behavior of the lifting pipe and mining vessel during the process of deep-sea mining using AQWA and OrcaFlex softwares.

Longitudinal vibration compensation model of stepped-pipe strings in deep-sea mining.

In this paper, the dynamic model of the rigid space stepped-pipe strings system is derived with Lagrangian method to represent the system dynamic behaviors which enriches the analysis method of longitudinal vibration of stepped-pipe strings. The stepped-pipe strings is constructed of pipes with different diameters and lengths, the physical properties of which mainly depends on the axial force and the depth of deep-sea mining. Based on lumped element method, the heave compensation system with dynamic vibration absorber is designed for longitudinal vibration suppression of the stepped-pipe strings.

[Preliminary study of intervention in effect of Bushen Huoxue recipe on calcification of lumbar vertebra cartilage endplate of the aging gerbils].

Objective: To study the effect of Bushen Huoxue decoction on calcification of cartilage endplate in lumbar vertebrae.

Methods: Six healthy male gerbils with 2-month-old were selected as normal control group, and 24 7-month-old healthy male gerbils were fed to 12-month-old to establish the aged gerbil model. Thirty gerbils were randomly divided into five groups as follow: the normal control group (=6), model group (=6, normal saline 4 ml/kg, intragastric 30 d), Bushen Huoxue low dose group(=6, 1.

[FTIR microspectroscopic investigation of the age-related changes of subchondral bone of the knee in guinea pig].

Fourier transform infrared (FTIR) microspectroscopy was applied to in-situ analyse the chemical change of tibial articular subchondral bone of female Hartley guinea pigs with age increase. Three infrared absorption regions (a, b, c) of trabecular bone and central marrow region of the subchondral bone were measured for guinea pigs of different ages (1 months, 2 months and 3 months) using the infrared spectrum. Results show that (1) with months increasing, the total area of trabecular bone is increasing, meanwhile, the region a which is similar to normal trabecular bone spectra is decreasing, and region d waveform has the same trend as region a.

[Investigation of articular cartilage using FTIR microspectroscopy for guinea pig with spontaneous osteoarthritis].

In-situ analysis the chemical composition of tibial articular cartilage of female Hartley guinea pigs with Fourier transform infrared (FTIR) microspectroscopy was conducted. The infrared spectrum survey consists of three ages (1 months, 2 months and 3 months) and three cartilage layers (surface, middle and deep). The results demonstrated that with ages increasing, the peak positions of main absorbance bands in surface and middle shifted to a lower wavenumber, and in deep they shifted to a lower wavenumber first, then shifted to a higher wavenumber.

[Preliminary investigation of animal model of tibial defection fracture made by drilling hole method ].

Objective: To compare the differences in damage degree, healing time and healing process between two animal models of defection fracture and provide the research data for the establishment of a new animal model.

Methods: Sixty male SPF Spragur-Dawley rats were divided randomly into control group, sawing group and drilling hole group, with 20 rats in each group. Animals of drilling hole group were treated with hone drill and made an 1 mm hole on tibial plateau animals of sawing group were treated with saw and made an 3 mm defection on tibial plateau; nothing to do in animals of control group.