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The low-temperature magnetic order behaviors of perovskite oxide CaCu3Ti4O12 (CCTO) ceramics prepared by different methods are discussed. X-ray diffraction, scanning electron microscope, x-ray photoelectron spectroscopy, and direct current (DC) magnetization are used to characterize the structures, microscopic morphologies, valence states, and magnetic properties of the samples. The results show that the magnetic behaviors of CCTO ceramics are very sensitive to the preparation process. The quenched CCTO ceramic and CCTO powders grown in a molten salt crystal, which contain much more oxygen vacancies and Ti3+, show the coexistence of weak ferromagnetic order and antiferromagnetic order below the Neel temperature. It suggests that the bound magnetopolaron formed by oxygen vacancies and Ti3+ ion composite defects are responsible for the weak ferromagnetic order at low temperature.

Chlorogenic acid, as a secondary metabolite of plants, exhibits a variety of effects including free radical scavenging, antiseptic, anti‑inflammatory and anti‑viral, in addition to its ability to reduce blood glucose, protect the liver and act as an anti‑hyperlipidemic agent and cholagogue. The present study demonstrated that administration of chlorogenic acid alleviated spinal cord injury (SCI) via anti‑inflammatory activity mediated by nuclear factor (NF)‑κB and p38 signaling pathways. Wistar rats were used to structure a SCI model rat to explore the effects of administration of chlorogenic acid on SCI. The Basso, Beattie and Bresnahan test was executed for assessment of neuronal functional recovery and then spinal cord tissue wet/dry weight ratio was recorded. The present study demonstrated that chlorogenic acid increased SCI‑inhibition of BBB scores and decreased SCI‑induction of spinal cord wet/dry weight ratio in rats. In addition, chlorogenic acid suppressed SCI‑induced inflammatory activity, inducible nitric oxide synthase activity and cyclooxygenase‑2 protein expression in the SCI rat. Furthermore, chlorogenic acid suppressed Toll like receptor (TLR)‑4/myeloid differentiation primary response 88 (MyD88)/NF‑κB/IκB signaling pathways and downregulated p38 mitogen activated protein kinase protein expression in SCI rats. The findings suggest that administration of chlorogenic acid alleviates SCI via anti‑inflammatory activity mediated by TLR4/MyD88/NF‑κB and p38 signaling pathways.

To compare the short term curative effect of posterior open door laminoplasty between continuous placement of shaping plate and intermittent placement in treating multilevel cervical spondylotic myelopathy.From January 2012 to March 2015, 43 patients with multi segment cervical spondylotic cervical were treated with posterior open door laminoplasty, 21 patients with continuous placement of shaping plate(continuous group), 22 patients with intermittent placement of shaping plate(intermittent group). Operative time, intraoperative blood loss, JOA score, VAS score, postoperative spinal sagittal diameter and cervical curvature, postoperative cervical activity, complications, hospitalization expenses etc. were observed.The patients of two groups were followed up with an average of (23.2±8.1) months and (23.3±8.0) months in continuous group and intermittent group, respectively. There was no significant difference in operative time, intraoperative blood loss, hospitalization time between two groups(Posterior open door laminoplasty with continuous or intermittent placement of shaping plate have similar clinical effects in ameliorating nerve function for the treatment of multilevel cervical spondylotic myelopahty. However, the hospitalization expenses of intermittent group is obviously reduced, and the medical resources can be saved.

The temperature and frequency dependence of capacitance versus voltage (C–V) curves was investigated for ceramic CaCu3Ti4O12 samples sintered in atmospheres of vacuum, air and oxygen, respectively. A drastic capacitance rise at higher dc voltages and low ac frequencies was observed for all these CaCu3Ti4O12CCTO samples, and it is especially strong for the sample sintered in vacuum, which has not been found previously. The shape as well as the asymmetry of the C–V curves suggest that the dielectric behavior is related to charged trap states. It also indicates that a slow relaxation process, which is strongly correlated with the re-positioning of oxygen vacancies related trap charges, takes place in CCTO. The main trap charge relaxation process is thought to occur between the boundaries perpendicular and parallel to the external electric field, and the anisotropy of the defect dipoles provide the possibilities for trap charge repositioning which maybe the reason of the huge dielectric constant.

To investigate the clinical effects and prevent the complications of posterior and anterior decompression and internal fixation in the revision of cervical anterior internal fixation failure.From 2008 January to 2011 December, 17 patients with cervical anterior internal fixation failure were treated with posterior and anterior decompression and internal fixation. There were 12 males and 5 females, aged from 26 to 68 years old with an average of 44.1 years. The lower screw loosening was found in 6 cases, the upper screw loosening in 5 cases, titanium mesh caving in 3 cases, the upper screw breakage in 2 cases, the lower screw breakage in 1 case. Informations of bone fusion were observed by X-ray, CT, MRI. Clinical effects were evaluated by modified JOA score.All the revision operations were successfully completed. One case with poor blood coagulation function before operation resulted in postoperative hematoma and occurred neurological symptoms; after hematoma removal and fresh frozen plasma infusion later, neurological symptoms of the patient disappeared. All patients were followed up from 6 to 38 months with an average of (22.4±10.0) months. Postoperative at 2 weeks, 3 months, and final follow-up, JOA score had obviously improved and respectively was 13.1±1.6, 13.4±1.6, 14.2±1.5. All internal fixation locations were good after revision,and obtained bone fusion at 10 months after operation, with an average fusion time of 6 months.The combined posterior and anterior decompression and internal fixation in the revision of cervical anterior internal fixation failure is safe, can achieve thoroughly decompression, maintain the cervical curvature, reconstruct the three column stability, and it may be used for the patients of cervical anterior fixation failure.

Brillouin measurements have been made of the spin dynamics of high-density two-dimensional hexagonally ordered 20 nm diameter Fe48Co52 nanowire arrays, with various interwire spacings, as a function of longitudinal magnetic field. The experimental data are analyzed within the Arias-Mills theory based on interwire dipolar couplings in the arrays. The results provide conclusive evidence of collective spin waves arising from the dipolar coupling which is manifested as a reduction in spin wave frequency with decreasing interwire spacing.

Ni(x)Pb(1-x) nanowire arrays were successfully fabricated by AC electrodeposition within the nanopores of ordered porous alumina films prepared by a two-step anodization. Transmission electron microscopy analyses showed that the Ni-Pb nanoarrays are polycrystalline with dimension uniformity around 20 nm in diameter and lengths up to several micrometers. X-ray diffraction results revealed that the face-centered-cubic (fcc) Ni and fcc Pb peaks are detected when the Ni component (x) is below 0.71, indicating that the Ni(x)Pb(1-x) nanoarrays do not form metastable phase alloy. Hysteresis loops determined by vibrating sample magnetometer indicated that the Ni(x)Pb(1-x) nanoarrays obtained possess obvious magnetic anisotropy, and the perpendicular coercivity was lower than that of pure Ni nanowries before and after annealing. Annealing under magnetic field was carried out to examine the effect of a magnetic field on magnetic properties using an electromagnet field up to 0.3 T.

To compare the therapeutic effectiveness of inverted less invasive stabilization system (LISS) and proximal femoral nail anlirotafion (PFNA) in treatment of complex unstable intertrochanteric fracture in aged, and to investigate the selective strategy of the internal fixation.From February 2007 to June 2009, 47 senior patients with complex and unstable intertrochanteric fractures (Evans IV, V, R-type) were treated. Among them 23 patients were treated by inverted LISS, including 7 males and 16 females, aged from 76 to 97 years; 24 patients were treated by PFNA, including 9 males and 15 females, aged from 73 to 90 years old. The mean operating time,blood loss, intraoperative photographs frequency, incision length, length of stay, bone healing,hip function were analyzed and compared.All patients were followed up for 8 to 18 months (averaged 13.1 months). All fractures got bone healing. No complications such as wound infection, varus and internal fixation cut out occurred. The operative time, incision length, in PFNA group had a slight ascendant than that in LISS inversion group, but there were no significant differences. According to postoperative Harris hip score outcome of LISS inversion group compared with the PFNA group, there was no significant difference.Both of PFNA and LISS have ideal effect in treatment of complex unstable intertrochanteric fracture in aged, and are good internal fixations.

The structure and magnetostriction of Dy0.9-xTbxPr0.1Fe1.85 and Dy0.9-xTbxPr0.1(Fe0.95Al0.05)1.8 alloys were investigated. These alloys are substantially single phase with MgCu2-type cubic structure. The lattice parameter and Curie temperature of Dy0.9-xTbxPr0.1(Fe0.95Al0.05)1.8 alloys increase steadily with increasing Tb content. Tb dependence of magnetostriction in various applied fields for polycrystalline Dy0.9-xTbxPr0.1Fe1.85 alloys exhibits a peak at x = 0.25. The magnetostriction of polycrystalline Dy0.9-xTbxPr0.1(Fe0.95Al0.65)1.8 alloys in high applied fields (H > 160 kA/m) and in low applied fields (H ≤ 160 kA/m) exhibits a peak at x = 0.3 and x = 0.25, respectively.

A small unknown signal, which shifts down linearly with temperature, was found by measuring electron paramagnetic resonance spectra in the colossal dielectric constant material CaCu3Ti4O12. This signal can be attributed to hopping electrons in CaCu3Ti4O12. In addition, the main Cu2+ signal split into two for the sample sintered in oxygen atmosphere. This may be due to the oxygen absorption into the crystal. Detailed analysis suggests that a copper–oxygen vacancy complex may be responsible for hopping conduction and oxygen absorption in CaCu3Ti4O12.