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Intertrochanteric fractures have become a severe public health problem in elderly patients. Proximal femoral nail anti-rotation (PFNA) is a commonly used intramedullary fixation device for unstable intertrochanteric fractures. Pelvic perforation by cephalic screw is a rare complication. We reported an 84-year-old female who fell at home and sustained an intertrochanteric fracture. The patient underwent surgery with PFNA as the intramedullary fixation device. Routine postoperative examination revealed medial migration of the helical blade that eventually caused pelvic perforation. We performed a cemented total hip arthroplasty as the savage procedure. At the latest follow-up of 12 months after total hip arthroplasty, the patient had no pain or loosening of the prosthesis in the left hip. Pelvic perforation should be considered when choosing PFNA as the intramedullary fixation device, especially in patients with severe osteoporosis wherein the helical blade can be easily inserted during the operation. The lack of devices to avoid oversliding of the helical blade in PFNA is an unreported cause of this complication and should be considered in such cases. [ABSTRACT FROM AUTHOR]

The structural and vibrational properties of 5% Sm-substituted BiFeO3 under pressure are investigated using synchrotron X-ray diffraction and Raman scattering measurements. The results yield the pressure-induced structural phase transitions from the polar R3c phase to the orthorhombic Pnma phase commencing at 3.9 and being complete at 7.6 GPa, where there is a region of the coexistence of the R3c and Pnma phases. This structural transition is companied by the ferroelectric-paraelectric transition for the Sm-substituted BiFeO3. We find that the Sm substitution leads to lower transition pressure compared to that of the pure BiFeO3 system due to the substitution-induced chemical pressure. Our results do not suggest the pressure-induced reentrance of ferroelectricity in the model multiferroic BiFeO3 in the pressure range studied. [ABSTRACT FROM AUTHOR]

The structural and magnetic properties of well-prepared Bi1-xNdxFeO3 (0 ≤ x ≤ 0.2) powders are investigated by combining x-ray diffraction, Raman scattering spectra, and magnetic measurements. Structural symmetric breaking from rhombohedral R3c to orthorhombic Pnma at the substituted Nd concentration of x = 0.125-0.15, accompanying a ferroelectric-antiferroelectric phase transition, is identified from x-ray diffraction patterns and Raman scattering spectra. The magnetization enhancement of Bi1-xNdxFeO3 is observed before approaching ferroelectric-antiferroelectric phase boundary conditions (0 ≤ x ≤ 0.15). We consider that such enhancement results from the destruction of the spin cycloid accompanying the structural transition. At x > 0.15, the magnetization decreases, which is probably attributable to further degradation of the space modulated spin structure, allowing a more perfect antiferromagnetic ordering. [ABSTRACT FROM AUTHOR]

Abstract: Structural, vibrational, and magnetic properties of Bi1−x Sm x FeO3 (0≤x≤0.20) are investigated by using x-ray powder diffraction, Raman scattering, and magnetometry techniques. We show that the rare-earth ion Sm substitution at Bi site, serving chemical pressure, causes the structural transformation from rhombohedral R3c phase to orthorhombic Pnma phase at x∼0.15, accompanying with the ferroelectric–paraelectric transition. The magnetization is found to be enhanced initially with Sm substitution increasing before approaching ferroelectric–paraelectric boundary but it slightly decreases after passing a maximum. The enhanced magnetization is suggested to stem from the combined effects of the suppressed spin cycloids and increased degree of canting and magnetic interactions between magnetic ions. [Copyright &y& Elsevier]

Abstract: Bi1−x Y x FeO3 (x=0–0.2) powders were prepared to study the effect of Y substitution on their structural and magnetic properties. A structural symmetric breaking from the rhombohedral R3c to orthorhombic Pnma at around x=0.10 was identified across a ferroelectric–paraelectric phase. A parabolic dependence of the magnetization upon substitution was obtained with a maximum at the phase transition boundary and a switching behavior for x=0.20. The composition-driven magnetic structure evolution was proposed to account for the magnetic properties in Bi1−x Y x FeO3. [Copyright &y& Elsevier]

Abstract: The structural, vibrational, and magnetic properties of well prepared Bi1−x Tb x FeO3 (x=0–0.2) powders are investigated by combining the X-ray diffraction, Raman scattering, and magnetometry measurements. It is found that partial substitution of Tb (10–12.5%) in Bi site results in a structural transformation from the rhombohedral R3c symmetry to the orthorhombic Pnma phase, accompanied by a ferroelectric–paraelectric phase transition. The magnetization of Bi1−x Tb x FeO3 first gradually increases before reaching maximum at the polar–nonpolar phase boundary and then decreases for x≥0.125 until x=0.20. The enhancement of the remnant magnetization is attributed to the suppression of the space-modulated spin structure in the rhombohedral R3c phase. Meanwhile, the reduction of the remnant magnetization in the orthorhombic Pnma phase is suggested to result from the establishment of well parallel antiferromagnetic ordering. [Copyright &y& Elsevier]

A combined process of denitrification-partial nitritation-ANAMMOX based on a zeolite biological aerated filter (ZBAF) was applied to treat mature landfill leachate. We investigate the partial nitritation characteristics of the ZBAF and the nitrogen removal performance as well as the carbon removal performance of the combined process. Results showed that, based on the selective inhibition of nitrite oxidizing bacteria (NOB) by free ammonia (FA), the ZBAF could successfully achieve stable and efficient partial nitrification of mature landfill leachate, with an average nitrite accumulation rate (NAR) of 93.8% and a maximum nitrite production rate (NPR) of 1.659 kg·(m 3 ·d) -1 . After adding 700 mg·L -1 glucose to the influent, due to the synergistic effect of denitrification and anammoxidation, the combined process achieved its best nitrogen removal performance at a reflux ratio of 2.0 and hydraulic retention time (HRT) of 2.2 days. The average ammonia removal efficiency (ARE), total nitrogen removal efficiency (NRE), total nitrogen removal loading rate (NRR), and average chemical oxygen demand (COD) removal efficiency were 97.2%, 90.0%, 0.585 kg·(m 3 ·d) -1 , and 45.3%, respectively. Furthermore, the NRR of the anaerobic ammonium oxidation (ANAMMOX) process (NRR ANA ) reached 1.268 kg·(m 3 ·d) -1 . High-throughput sequencing technology was used to analyze the microbial community structure in each device. Results showed that denitrifiers ( Paracoccus and Comamonas ), ammonia-oxidizing bacteria (AOB) ( Nitrosomonas ), and ANAMMOX bacteria ( Candidatus Kuenenia and Candidatus Anammoxoglobus ) were the dominant bacteria in the UASB, ZBAF, and ANAMMOX reactor, respectively, which corresponded to the stable nitrogen removal performance of the combined process.