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To enhance the joint’s properties for AISI 321 steel, due to the limitations of conventional joining methods, transient liquid phase bonding was investigated for this steel in order to achieve the optimum process parameters. In this way, the effects of bonding temperature (1050 to 1200 °C) and time (30 to 120 min) on microstructure and shear strength of the AISI 321/MBF-20/AISI 321 and AISI 321/MBF-30/AISI 321 joints were studied. Results showed that while incomplete isothermal solidification of the samples results in the formation of Fe–B, Cr–B, Ni–Si, and Ni–B phases at the centerline of the joints and diffusion-affected zone, more homogenous joints with higher shear strength values were obtained with the increase in bonding temperature and time. In addition, it was found that the presence of Fe and Cr in chemical composition of MBF-20 interlayer increased the amount of eutectic compounds at the centerline of joints and the amount of precipitates at heat-affected zone. Furthermore, it was found that regardless of the type of interlayer, the increase in bonding temperature from 1050 to 1150 °C increased the shear strength of the joints. The highest shear strength occurred in AISI 321/MBF-30/AISI 321 system bonded at 1150 °C for 60 min that was 99% of that of the base metal. Also, it was found that further increase in the bonding temperature beyond 1150 °C reduced drastically the shear strength of the bonds due to the occurrence of partial melting, especially at the grain boundaries of base metal. In addition, the study of the fracture surface of the joints showed that samples with high shear strength values were fractured by ductile mode. However, features of brittle fracture were observed in the fracture surface of the samples with lower shear strength values.

MBF20 interlayer, as a commercial foil, was used for TLP bonding of IN738/MBF20/IN718 system at different temperatures and times. Microhardness and shear strength tests were conducted for all the samples. Hardness profile across the joints made at 1050 and 1100 °C revealed the microstructure regions as isothermal solidification zone (ISZ), athermal solidification zone (ASZ), and diffusion affected zone (DAZ). With increasing bonding time at each temperature, hardness peak at the joint centerline was removed but the hardness peak at DAZ remained. Increase of joint’s shear strength, increase of ISZ hardness, and decrease of DAZ hardness with increasing bonding temperature and/or time were discussed according to the effect of Larson-Miller parameter. Partial liquation of the base metals at 1150 °C/60 min condition caused reverse trend for variation of hardness and joint’s strength with bonding temperature. Fracture path of the joints with incomplete isothermal solidification was seen through the centerline eutectics. This path for the joints with complete isothermal solidification was observed through the bonding zone and the DAZ phases.

Subchondral bone marrow lesions (BMLs) are a risk factor for knee OA outcomes and deep-learning (DL) methods can help in automated segmentation and risk prediction.

Bone marrow lesions (BMLs) are a risk factor for incident knee OA and deep-learning (DL) methods can help in automated segmentation and risk prediction.

The present work describes the reactions of wet process synthesis, of some calcium phosphates, such as tricalcium phosphate (Ca3(PO$_{4})_{2})$and hydroxyapatite (Ca10(PO$_{4})_{6}$(OH)$_{2})$. These reactions of synthesis are acido-basic reactions between the phosphoric acid (H3PO$_{4})$and calcium carbonates (CaCO$_{3})$.The evolution of these reactions (and the concerned chemical mechanisms) were followed by mid infrared spectroscopy absorption. Indeed, in the first stage of these three reactions in which the medium is strongly acidic, favours the formation of a stable intermediate compound, which is the brushite.During the reaction, the concentration of phosphoric acid decreases, the pH increases and the brushite becomes unstable, thus it evolves to a more stable calcium phosphate under these new pH conditions. This later product was either the tricalcium phosphate or hydroxyapatite, according to the pH solution.

Abstract: Hydrogen peroxide/MoO3, as an efficient and clean oxidizing system was used to afford diasteroselective oxidative cyclization of bisnaphthols to spirans in ethanol at 60 °C with high yields. Bisnaphthols were prepared by the reaction of a series of aldehydes and 2-naphthol in the presence of a catalytic amount of H3[P(Mo3O10)4].nH2O (HPa) in refluxing dichloromethane.

Levothyroxine, the primary treatment for hypothyroidism, is prescribed for more than 7% of Americans. Levothyroxine use, or the underlying hypothyroidism can be associated with musculoskeletal symptoms; however, no prior work has investigated this association using sensitive biomarkers.

Diabetes mellitus (DM) and specifically hyperglycemia, can affect skeletal muscle mass and strength and Studies have shown knee OA, and DM frequently coexist in patients. The exact mechanisms by which DM may contribute to KOA worsening remain poorly understood.

Thigh muscles play an important role in knee joint biomechanical stability, and changes in their size and quality are associated with knee OA incidence. There are currently no known disease-modifying medications for mitigating knee OA-related symptom worsening and delaying TKA. Therefore, non-surgical, non-pharmacological approaches targeting thigh muscle strengthening and composition have important clinical implications. The structural therapeutic effects of such interventions can be quantified using muscle MRI. However, no conclusive longitudinal data is available on the association of quantitative thigh muscle MRI markers with knee OA-related clinical outcomes.

Subjective statin-associated musculoskeletal symptoms such as myalgia are commonly reported and contribute to statins' non-adherence. Several trials have recently suggested that in the absence of rare myositis, such symptoms are probably a placebo effect. However, no longitudinal study has been conducted to investigate whether statin use can be associated with deterioration in muscle quality. Such an association can be of particular clinical concern in older patients with or at-risk of knee OA, in whom muscle changes can affect the knee OA clinical outcomes.