The low cellular activity of poly-l-lactic acid (PLLA) limits its application in bone scaffold, although PLLA has advantages in terms of good biocompatibility and easy processing. In this study, superparamagnetic Fe₃O₄ nanoparticles were incorporated into the PLLA bone scaffold prepared by selective laser sintering (SLS) for continuously and steadily enhancing cellular activity. In the scaffold, each Fe₃O₄ nanoparticle was a single magnetic domain without a domain wall, providing a micro-magnetic source to generate a tiny magnetic field, thereby continuously and steadily generating magnetic stimulation to cells. The results showed that the magnetic scaffold exhibited superparamagnetism and its saturation magnetization reached a maximum value of 6.1 emu/g. It promoted the attachment, diffusion, and interaction of MG63 cells, and increased the activity of alkaline phosphatase, thus promoting the cell proliferation and differentiation. Meanwhile, the scaffold with 7% Fe₃O₄ presented increased compressive strength, modulus, and Vickers hardness by 63.4%, 78.9%, and 19.1% compared with the PLLA scaffold, respectively, due to the addition of Fe₃O₄ nanoparticles, which act as a nanoscale reinforcement in the polymer matrix. All these positive results suggested that the PLLA/Fe₃O₄ scaffold with good magnetic properties is of great potential for bone tissue engineering applications.

The too fast degradation of magnesium (Mg) alloys is a major impediment hindering their orthopedic application, despite their superior mechanical properties and favorable biocompatibility. In this study, the degradation resistance of AZ61 (Al 6 wt. %, Zn 1 wt. %, remaining Mg) was enhanced by rapid solidification via selective laser melting (SLM). The results indicated that an increase of the laser power was beneficial for enhancing degradation resistance and microhardness due to the increase of relative density and formation of uniformed equiaxed grains. However, too high a laser power led to the increase of mass loss and decrease of microhardness due to coarsened equiaxed grains and a reduced solid solution of Al in the Mg matrix. In addition, immersion tests showed that the apatite increased with the increase of immersion time, which indicated that SLMed AZ61 possessed good bioactivity.

Tetracalcium phosphate (TTCP), a potential biological scaffold material, has attracted increasing interest for bone regeneration applications due to its good biodegradability and biocompatibility. In this research, three-dimensional porous TTCP scaffolds were manufactured via selective laser sintering (SLS), and an in-depth and meticulous study on the influence of laser power on the microstructure and mechanical properties of TTCP scaffolds was performed. The results showed that the TTCP particles fused together and formed a solid object due to the decrease in the number of micro-pores in the scaffold as the laser power increased from 6 W to 9 W. The maximum compressive strength that the scaffold could withstand and the strength of the fracture toughness were 11.87 ± 0.64 MPa and 1.12 ± 0.1 MPa·m^1/2, respectively. When the laser power increased from 9 W to 10 W, the TTCP grains grew abnormally, resulting in diminished mechanical properties. The bioactivity tests showed that the surfaces of the scaffolds were entirely covered by bone-like apatite layers after soaking in simulated body fluid (SBF) for three days, indicating that the scaffolds exhibit excellent bioactivity. Moreover, cell experiments showed that the TTCP scaffolds had good biocompatibility. This study indicated that SLS-fabricated TTCP scaffolds may be a promising candidate for bone regeneration applications.

Large-sized lateral ZrS ₂ nanosheets up to 22 μm were synthesized using a gas-phase alkali halide precursor, showing high crystallinity and a uniform surface and exhibiting field effect transistors behaviour.

Background: Cone beam CT (CBCT) has been reported for intensity‐modulated radiation therapy (IMRT) of various cancers due to its real‐time imaging capabilities, but studies on its application in orbital diseases, particularly moderate to severe thyroid‐associated ophthalmopathy (TAO), remain limited. Purpose: To investigate the clinical applications of CBCT in IMRT for TAO, with a focus on setup accuracy, dosimetric impact, and short‐term changes in eye prominence. Methods: A total of 115 CBCT scans from 17 TAO patients were analyzed. Pretreatment CBCT scans were registered to the planning CT using bony anatomy. The resulting setup errors were quantified in three translational directions. Residual shifts after online correction were tracked to assess interfractional variation and trends throughout the treatment course. Dose‐volume histogram from plans recalculated with simulated setup errors (mean and maximum values) were compared to the original plan. Eye prominence was measured on serial CBCT scans, and its correlation with cumulative dose was analyzed. Results: Mean setup errors were (–0.16 ± 1.09) mm, (–0.19 ± 1.18) mm, and (–0.55 ± 1.05) mm in X, Y, and Z directions. Errors significantly decreased planning target volume (PTV) conformity ( p < 0.05) and increased D _mean , D _max , D _2%, and D _50% ( p < 0.05). For organs at risk (OARs), maximum and mean doses increased, with left lens D _max increasing by 21.3%, 32.7%, 33.8%, and 13.2% for mean setup errors and X, Y, and Z maximum errors. Right lens showed similar increases. A correlation between CBCT‐measured eye prominence and total radiotherapy dose was observed, with the binomial fit: y = 22.43 + 0.12x − (9.94 × 10 ⁻³ ) x ² ( R ² = 0.96). Mean eye prominence decreased significantly from (21.74 ± 1.74) mm pre‐treatment to (20.94 ± 1.73) mm after 18 Gy of IMRT ( p < 0.05). Conclusion: CBCT image guidance for IMRT in moderate to severe TAO improves target conformity and coverage while reducing OAR doses, particularly for lenses. CBCT also shows promise for short‐term efficacy assessment of eye prominence in radiotherapy patients which may alleviate patient anxiety with preliminary observation thereby improving patient compliance with radiotherapy.