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Notes: The anterior cingulate cortex (ACC) is thought to be important for the establishment, consolidation and retrieval of permanent memory. In many brain regions, including the hippocampus, it is suggested that long-term potentiation (LTP) and long-term depression (LTD), the cellular mechanisms for learning and memory, require the activation of glutamate N-methyl-d-aspartate receptors (NMDARs). In the hippocampus, the NR2A subunit is believed to be involved in the induction of LTP, whereas the NR2B subunit contributes to the formation of LTD. However, LTD has been less well studied in the ACC as compared with the hippocampus and little is known about the role of NMDA subtype receptors in cingulate LTD. Here we show that LTD can be induced by the combination of presynaptic stimulation with postsynaptic depolarization (‘pairing training’) in adult mouse ACC neurons. This form of LTD is an NMDAR- and voltage-dependent mechanism and a postsynaptic Ca2+ increase is required for the induction of LTD. Furthermore, our studies provide direct physiological evidence that both NR2A and NR2B subunits are involved in the induction of LTD in the ACC.

Notes: Objective:  Antineutrophil cytoplasmic autoantibodies (ANCA) were found in patients with systemic lupus erythematosus (SLE). Cathepsin G and lactoferrin were the major target antigens. However, some ANCA-positive sera did not recognize either of them. The present study was to investigate the unknown target antigens of ANCA in patients with SLE and their clinical significance.Methods:  Sera were collected from 72 patients with SLE. ANCA were detected in both indirect immunofluorescence and antigen-specific enzyme-linked immunosorbent assay (ELISA). Mixed neutrophil granules were separated from normal human peripheral neutrophils; soluble acid extracts in non-reducing conditions were used as antigens in western blot analysis to detect ANCA.Results:  SLE sera could blot a few bands. Interestingly, 14/72 (19.4%) sera recognized a novel 69 kDa protein band and 10/72 (13.9%) sera recognized the 55 kDa protein band, which might be bactericidal/permeability-increasing protein (BPI). The 69 kDa target antigen was different from the known target ANCA antigens such as cathepsin G and lactoferrin. Further study revealed that the percentages of patients with photosensitivity and oral ulcer in the anti-69 kDa autoantibodies-positive group were significantly higher than those in the anti-69 kDa autoantibodies-negative group (57.1%vs 10.3%, P 〈 0.005 and 50.0%vs 12.1%, P 〈 0.05, respectively).Conclusions:  A 69 kDa protein in human neutrophil granules was identified as a novel target antigen of ANCA in patients with SLE. The anti-69 kDa autoantibodies might be associated with photosensitivity and oral ulcer in patients with SLE.

Notes: Bending and impact tests were conducted on magnesium alloys AZ31 and AZ80 indifferent microstructure conditions. It is found that the strength parameters are increased quite a lot,and the ductility parameters (bending flection) decreased with increase in strain rate. The damagedsurface analysis in SEM revealed that, the micro crack nucleation modes, micro crack coalescenceand final crack path are varied with the stress state on the specimen, and the crack nucleation modesare varied with the initial strain rate. The effect of strain rate on fracture modes is discussed

Notes: The influence of ultrasonic vibration on the surface roughness and micro-topography ofceramics plate is discussed in this paper. Grinding assisted by two-dimensional ultrasonic vibration isdeveloped to deal with the processing difficulty of ceramic materials due to its hard-brittle property.The experimental results show that the surface roughness value obtained in two-dimensionalultrasonic grinding nano-ZrO2 ceramic plate specimen is obviously smaller than that in commongrinding, and the scratched grooves on the machined surface in ultrasonic grinding is wider andrelatively smoother than that in common grinding. Consequently, it proves that the two-dimensionalultrasonic machining is a feasible, high-efficient machining method for hard-brittle materials

Notes: In this paper, homogeneous and well-crystallized LiFePO4 was synthesized by a novelmodified solid-state reaction method following by heat treatment at relatively low temperature of 500°Cin Ar. No impurities are detected in the XRD patterns. The initial charge specific capacity and dischargespecific capacity reach 157.2mAhg-1 and 152.6mAhg-1 respectively at 20°C. Voltage plateaus at around3.45V were observed in all the curves, indicating that the charge and discharge reaction proceeds as atwo-phase reaction. The initial charge specific capacity is 157.2mAhg-1 at 0.1C rate, i.e. 92% of thetheoretical capacity, and specific capacity decreases slightly after 100 circles at room temperature

Notes: A chromium-free conversion coating for AZ91D magnesium alloys has been obtained by using a phosphate-permanganate solution. Examinations have been carried out on the conversion coating for morphology, composition, adhesion force and corrosion resistance. Results show that the conversion coatings are relatively uniform and continuous, with thickness from 7µm to 10µm. They exhibit good adhesion to matrix and have some non-penetrate tiny holes on the surface. Themain elements of the conversion coating of AZ91D alloy are Mg、O、P、K、Al、Mn. Results of corrosion resistance test indicate that the corrosion resistance of the conversion coating by phosphate-permanganate solution is in match to that of the conversion coating formed in a chromate solution, but for the corrosion resistance after painting, the former is better than the later

Notes: The dielectric ceramics comprised of (Zn1-xMgx)TiO3 (x=0.1~0.5, abbreviated to ZMT)were developed by conventional mixed-oxide method combined with a semi-chemical processing.V2O5 was used as sintering aids to lower the sintering temperature of ceramics. The results showedthat the hexagonal phase stability region extended from 900 to 1150°C as the amount of magnesiumincreased. The densification temperature of ZMT ceramics could be reduced from 1200 to 875°C byV2O5 additions and using semi-chemical processing, the relative density of ZMT ceramics with1.00wt% V2O5 addition reach 95% at 875°C. The dielectric properties of ZMT were measured atdifferent frequencies and the results showed that there existed a decreasing tendency of the losstangents (tg δ) with increasing measuring frequency. It is concluded that εr=22 and tg δ= 5.7×10-4 canbe obtained for ZMT ceramics at sintering temperature 875°C

Notes: The nitrogen-doped TiO2 thin films were prepared by mid-frequency alternative reactive magnetron sputtering technique. The N concentration of the nitrogen-doped TiO2 thin films was analyzed by XPS. And the absorption spectra of the films in ultraviolet and visible region were also investigated. The results show that the mid-frequency alternative reactive magnetron sputtering technique is a convenient method for growing TiO2-xNx. Annealing the nitrogen-doped TiO2 thin film in nitrogen atmosphere under 380°C is helpful for increase the concentration of nitrogen in the film, but the ratio of N2 in reactive gas is mainly influence the concentration of nitrogen in the Ti-N bond in the TiO2 film. The increase of the thickness of nitrogen-doped TiO2 films will enhance the absorbability of the film in the ultraviolet and visible region. The wavelength of the absorption edge of TiO2-xNx film with 1.5% nitrogen shift to 441nm from 387nm, which is the absorption edge for undoped TiO2 films

Notes: Natural bone is a typical example of an “organic matrix-mediated” biomineralizationprocess which constituted of hydroxyapatite(HA) nanocrystals orderly grown in intimate contactwith collagen fibers. Bone morphogenetic protein 2 (BMP2) is the most powerful osteogenic factor.But it is extremely difficult to be manufactured in large scale. In previous study, we have designed anovel oligopeptide (P24) derived from BMP2 knuckle epitope and it contained abundantAsp(aspartic acid) and phosphorylated Ser(serine) which may be helpful for self-assamblybiomineralization and osteogenesis. Previous In vivo experiments have shown that this noveloligopeptide had excellent osteoinductive and ectopic bone formation property which was similar tothat of BMP2. In this study, PLGA-(PEG-ASP)n scaffolds were modified with P24 and a newbiomimetic bone tissue engineering scaffold material with enhanced bioactivity was synthesized bya biologically inspired mineralization approach. Peptide P24 was introduced intoPLGA-(PEG-ASP)n scaffolds using cross-linkers. Then the P24 modified scaffolds and the simplePLGA-(PEG-ASP)n scaffolds were incubated in modified simulated body fluid (mSBF) for 10 days.Growth of HA nanocrystals on the materials was confirmed by observation SEM and measurementsEDS and XRD. SEM analysis demonstrated the well growth of bonelike HA nanocrystals on P24modified PLGA-(PEG-ASP)n scaffolds than that of the control scaffolds. The main component ofmineral of the P24 modified scaffolds was hydroxyapatite containing low crystalline nanocrystals,and the Ca/P ratio was nearly 1.60, similar to that of natural bone, while that of the control scaffoldswas 1.52. The introduction of peptide P24 into PLGA- (PEG- ASP)n copolymer provides abundantactive sites to mediate the nucleation and self- ssembling of HA nanocrystals in mSBF. the resultedpeptide P24 modified- HA/PLGA- (PEG- ASP)n composite shows some features of natural boneboth in main composition and and hierarchical microstructure. This biomimetic treatment providesa simple method for surface functionalization and subsequent biomineralization on biodegradablepolymer scaffolds for tissue engineering

Notes: The effects of pre-synthesized V2O5/Sb2O3 compound, SbVO4 and Sb2O3 on the microstructureand electrical properties of ZnO-V2O5 based varistor ceramics have been studied. The general homogeneousmicrostructure and phase composition of the ceramics have not been influenced by the antimonydoping form changes, except for the gradual decrease in average grain size and the increase in spinelformation within the ceramics. The ultimate cause of micro-structural variations with the antimonydoping form changes seems to have been the gradual increase in Sb3+ concentration within the ceramics.This change in micro-composition, together with the changes in microstructure, caused the electricalcharacteristics of the ceramics to vary. The pre-synthesized V2O5/Sb2O3 compound is the most effectiveantimony dopant in term of its effect on the ceramics