Objectives: Although sarcopenia and osteoporosis are inter related conditions that are common with advancing age, few studies have explored relationships between muscle quality and bone mineral density (BMD). We investigated age and sex-specific paraspinal muscle fat infiltration (MFI), muscle cross-sectional area (CSA), and spine volumetric BMD (vBMD) in healthy Chinese adults. Methods: 605 healthy adults aged 20-59y (340 women, mean age 39.2y; 265 men, mean age 38.8y) had axial T2WI MRI imaging of the lumbar spine and CSA (cm2) and MFI (%) were measured in the psoas and multifidus and erector spinae (MF-ES) muscles (L3-L4). MFI measurements were calibrated against a region of interest in an adjacent area of subcutaneous pure fat. L2-L4 vBMD was measured by quantitative computed tomography. Age and sex-specific subgroups were compared using the Mann-Whitney test. Multiple regression was used to test independent associations of MFI and CSA with vBMD. Results: Females had lower CSA and higher MFI than males in both the psoas and MF-ES muscles (p < 0.001). In females and males, MF-ES MFI increased with age (p < 0.001) and in females age-related increases were observed for the psoas muscles (p < 0.05). Greater fat infiltration of the MS-ES muscle unit was associated with lower vBMD in both sexes (p < 0.001) but not with CSA. Following adjustment for demographic variables and CSA, MS-ES MFI remained predictive of vBMD (β = −0.408 to −0.157, p < 0.001). Conclusions: We have demonstrated that, independent of CSA and demographic variables, MFI of the MF-ES muscles is predictive of lower lumbar spine vBMD in both sexes. Advances in knowledge: This is the first study to demonstrate that, independent of muscle size and demographic variables, MFI of the paraspinal MF-ES muscles is predictive of lower lumbar spine vBMD in both sexes.

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In this paper, the latest research development on the heat treatment processes, microstructure and mechanical properties of low-carbon martensite steel was reviewed. And the effects of heat treatment processes on the microstructure and mechanical properties of low-carbon martensite steel were analyzed.

The magnetic shape-memory alloy NiCoMnIn shows, in monocrystalline form, a large reversible magnetic-field-induced strain (MFIS). But it is difficult to achieve the properties in polycrystalline NiCoMnIn alloys. The technique of powder metallurgical preparation of NiCoMnIn foam was studied to improve the properties of polycrystalline NiCoMnIn alloys in the present paper. We introduced a processing route including choosing appropriate space-holding fillers, sintering NiCoMnIn alloy and the filling agent with appropriate grain size. The sintering temperature and time and the optimum volume fraction of the filling agent were determined by analysis of the structure of sintered bulk foams.

The microstructure characters of pure Iron during cold rolling were studied by HEXD (high-energy x-ray diffraction). The experimental result shows that the Debby ring of HEXD before cold rolling is discrete and very strong, the discrete diffraction points become continue and smooth with the increase of cold rolling reduction. The {001}<110> textures transform to the {001}<uvw> texture after cold rolling, in this process the grains divisional are analyzed by the HEXD result.