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Parkinson's disease (PD) is typically a sporadic late-onset disorder, which has made it difficult to model in mice. Several transgenic mouse models bearing mutations in SNCA, which encodes alpha-Synuclein (a-Syn), have been made, but these lines do not express SNCA in a physiologically accurate spatiotemporal pattern, which limits the ability of the mice to recapitulate the features of human PD. Here, we generated knock-in mice bearing the G51D SNCA mutation. After establishing that their motor symptoms begin at 9 mo of age, we then sought earlier pathologies. We assessed the phosphorylation at Serine 129 of a-Syn in different tissues and detected phospho-a-Syn in the olfactory bulb and enteric nervous system at 3 mo of age. Olfactory deficit and impaired gut transit followed at 6 mo, preceding motor symptoms. The SncaG51D mice thus parallel the progression of human PD and will enable us to study PD pathogenesis and test future therapies. [ABSTRACT FROM AUTHOR]

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In this paper, the effects of material removal strategies and initial stress states on the machining deformation of aluminum alloy plates were investigated through a combination of finite element simulation and experiments. We developed different machining strategies described by Tm+Bn, which removal m mm materials form top and n mm materials from the bottom of the plate. The results demonstrate that the maximum deformation of structural components with the T10+B0 machining strategy could reach 1.94 mm, whereas with the T3+B7 machining strategy was only 0.065 mm, decreasing by more than 95%. The asymmetric initial stress state had a significant impact on the machining deformation of the thick plate. The machined deformation of thick plates increased with the increase in the initial stress state. The concavity of the thick plates changed with the T3+B7 machining strategy due to the asymmetry of the stress level. The deformation of frame parts was smaller when the frame opening was facing the high-stress level surface during machining than when it was facing the low-stress level. Moreover, the modeling results for the stress state and machining deformation were accurate and in good accordance with the experimental findings. [ABSTRACT FROM AUTHOR]

The effects of solution temperature and holding time on the microstructure, mechanical properties and surface morphology of 2A12 aluminum alloy sheets were discussed in this paper. The universal tensile tester was used to test the tensile strength and yield strength of aluminum alloy sheets with different treatment systems. The surface morphology of the alloy sheets was characterized by a white light interference profile scanner, and the microstructure of the sheets was characterized by optical microscope (OM), scanning electron microscope (SEM) and electron backscattered diffraction (EBSD). The results showed that the mechanical properties of the sheets could not satisfy GBT228.1-2010 national standard when the holding time was 10 min and the holding temperature was 475 °C. However, under the other heat treatment systems, the alloy could reach the GBT228.1-2010 national standard. Moreover, with the extension of the holding time, the part of the matrix gradually diffused into the aluminum-clad layer. When the holding time was shorter than 25 min, the boundary between the matrix and the aluminum-clad layer was relatively obvious. And the diffusion gradually became obvious when the holding time was over 25 min. Thereby, the boundary became blurry. The further investigation suggested that the solution temperature of 495 °C and the holding time of 35 min showed better mechanical properties and better surface morphology. [ABSTRACT FROM AUTHOR]

The increase in zinc content in Al–Zn–Mg–Cu alloys provides an effective method to enhance the strength. Transmission electron microscopy (TEM) and tensile test were employed to analyze the microstructure and tensile properties, respectively, of Al–9.3Zn–2.0Mg–1.8Cu alloy (9.3Zn alloy) and Al–9.8Zn–2.0Mg–1.8Cu alloy (9.8Zn alloy) with single- and double-stage aging states. The results showed that the two alloys possessed a closed strength under single-stage peak-aging treatment. As for double-stage aging treatment, 9.8Zn alloy had a higher strength values than 9.3Zn alloy under the same aging regimes. With the second step aging time prolonging, the strength gap was extended. The main precipitates for the two alloys with single-stage peak-aging state were GP zones and η′ phase, while there were a majority of η′ phases and η phases for the two alloys under typical double-stage over-aging state. Under double-stage over-aging state, the proportion of precipitate with large size for 9.3Zn alloy was larger than that for 9.8Zn alloy. Besides, a more obvious trend was revealed for the double-stage over-aging state. The gap of strength between the two alloys was explained by the difference of precipitation characteristics via interaction mechanism between precipitates and dislocations. [ABSTRACT FROM AUTHOR]

The transformation behavior of precipitates in Al–Mg–Si–Cu alloys with and without Zn addition during artificial aging at 170 °C was investigated in this study. For Al–Mg–Si–Cu alloys with and without Zn addition, two types of precipitates, needle-like β″ and lath-like L, are formed with the aging time increasing from 8 to 34 h. The needle-like β″ precipitate exhibits a Mg-to-Si atomic ratio of 1.31 which is in agreement with the theoretical ratio of 1.25 for β″ (Mg5Al2Si4). In addition, the β″ precipitate is supposed to contain Al and Cu. With further partitioning of Mg, Si and Cu and release of Al, the needle-like β″ precipitate can transform to lath-like L phase. The L phase has significantly higher concentrations of Mg, Si and Cu and lower concentration of Al, with a higher Mg-to-Si atomic ratio (1.41) deviated from theoretical ratio of β″. However, the major of Zn has a random distribution in Al matrix and exhibits no significant partitioning into precipitates. Zn remained in matrix can enhance the transformation of β″ precipitates to L precipitates. [ABSTRACT FROM AUTHOR]

The effect of solution treatment on the microstructure and mechanical properties of a novel 7A56 aluminum alloy plate was investigated by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), conductivity, hardness and tensile tests. The results indicate that the coarse second phases in the hot-rolled plate mainly consist of AlZnMgCu quaternary phase and Al7Cu2Fe phase, and no Al2CuMg phase is found. The amount of the second phases gradually reduces with the increase in temperature (450–480 °C) and time (1–8 h) during the solution treatment, and the soluble particles are completely dissolved into the matrix after solution treatment at 470 °C for 4 h, while the residual phases are mainly Fe-rich phase along the grain boundaries. The recrystallization fraction of the alloy gradually increases with the degree of solution treatment deepened. When the temperature exceeds 480 °C, over-burning takes place. The mechanical properties of samples treated at 470 °C for various times were tested. After the solution treated at 470 °C for 4 h, the quenching conductivity and peak-aged hardness of the alloy are 30.8%IACS and HV 204, respectively. The ultimate tensile strength and yield strength of the samples aged at 120 °C for 24 h are 661 and 588 MPa, respectively. [ABSTRACT FROM AUTHOR]

The effect of copper content on quench sensitivity in novel Al–Zn–Mg–Cu alloys containing high zinc content was investigated by Jominy end quench test. Electrical conductivity and hardness test, temperature collecting, and transmission electron microscopy (TEM) technique were adopted for the properties and microstructure characterization of three alloys with different copper contents. The results indicate that the electrical conductivity of all three alloys increases with the increase of distance from the quenched end, while the hardness shows an opposite trend. If the dropping of 10% hardness is defined as the critical evaluation standard of quenching, the depth of quenched layer of Alloys I, II, and III are 70, 55, and 40 mm, respectively. The precipitation behavior on grain boundaries of three alloys is similar except for a little difference in size, while the size of precipitates in grains of Alloy III with higher copper content is larger than those of the other two alloys at the same location. Considering all results, the stability of the supersaturated solid solution of Alloy III is lower than those of the other two alloys, meaning that Alloy III shows the highest quench sensitivity. Higher copper content leads to higher quench sensitivity in novel Al–Zn–Mg–Cu alloys with the same content of magnesium, zinc, and other trace elements. [ABSTRACT FROM AUTHOR]

Background: Protein Kinase C-α (PKC-α) and epidermal growth factor receptor (EGFR) are both involved in diabetic kidney disease; however, the connection between these two proteins during high glucose-induced podocyte injury remains uncertain. Methods: Diabetes was induced in SD rats by streptozotocin (STZ). Fourteen days later, the kidney cortex was removed and subjected to plasma membrane isolation and lipid raft fractionation. In vitro study human podocyte cell line was differentiated and subjected to various treatments. The levels of membranous protein and endocytosis were assessed by biotinylation and sodium 2-mercaptoethane sulfonate (MesNa) treatment. Go6976 and PYR-41 were used as inhibitors of PKC-α and ubiquitin activating E1 enzyme, respectively. Results: In diabetic rats, the abundance of PKC-a in the membranous fraction and the lipid raft domain is elevated, whereas the EGFR level is reduced. Consistently, in vitro high glucose treated podocytes, membranous EGFR is downregulated with increased PKC-α. Furthermore, the ubiquitination and endocytosis of EGFR are enhanced accompanied by extracellular signal-regulated kinase (ERK) signaling activation and podocyte damage during hyperglycemia. However, these processes can be ameliorated by inhibition of either PKC-α or ubiquitin activating E1 enzyme. Conclusion: During hyperglycemia, PKC-α mediates podocytic EGFR ubiquitination, endocytosis from cell surface and the subsequent ERK activation, which contributes to podocyte injury. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to assess the feasibility and accuracy of 3-D ultrasound indices to evaluate fetal lung maturity, and to establish a normal reference for fetal lung volume (FLV) and fetal lung-to-liver intensity ratio (FLLIR) in a Chinese population. Methods A total of 1022 pregnant women with singleton pregnancy were prospectively studied between June 2008 to June 2011. Ultrasound examination was performed. The breathing-related nasal fluid flow (BRNFF) spectrum, FLV, pulmonary artery blood flow parameters, and echo intensity of the lung were calculated. Phosphoglycerides in the amniotic fluid were measured on thin layer chromatography. Results FLLIR and FLV were positively and linearly correlated with gestational age (F = 0.915, 0.846). Indicators of fetal lung maturity included FLLIR >1.1, FLV >50 mL, and regular BRNFF spectrum, with positive likelihood ratios of 12.28, 11.78, and 11.63, independently. Conclusion Ultrasound indices, including FLLIR, FLV and BRNFF may serve as useful alternatives to amniotic fluid phospholipids in analyzing fetal lung maturity in Chinese patients. [ABSTRACT FROM AUTHOR]

Polarization singularities, which emerge from the incoherent superposition of two vector electric fields with the same frequency, and their evolution in free space are studied analytically and illustrated by numerical examples. It is shown that there exist C-points, L-lines, in particular, C-lines in incoherently superimposed two-dimensional wavefields. Usually, the C-lines are unstable and disappear during the free-space propagation. The motion, pair creation{annihilation process of the emergent C-points, as well as the distortion of the L-lines may take place, and the degree of polarization of the emergent C-points varies upon propagation and may be less than 1. [ABSTRACT FROM AUTHOR]

The article describes dinuclear double-helical complex called bis[μ-N,N'-bis(quinolin-8-yl)pyridine-2,6-dicarboxamido]dizinc(II) dichloromethane disolvate. The research was part of the study on the design of double and triple helicates due to their structural and superstructural diversity. These helical compounds have potential applications also in medicinal chemistry, nonlinear optics, asymmetric catalysis and luminescence.

Spinal cord injury without radiographic abnormality (SCIWORA) is a rare condition seen in adults. Many interbody fusion cages have been developed for its treatment, but clinical studies of Fidji cervical cage are still scarce. A total number of five patients (four male and one female) were reviewed. The ages of the patients ranged from 40 to 60 years. All the patients underwent neurological and radiological examinations. Neurological and functional outcomes were assessed on the basis of Frankel's grade. Three of the patients were Frankel B, and the rest two were Frankel C. Magnetic resonance imaging was also performed for the evaluation of spinal cord and intervertebral disc injury. Anterior cervical discectomy and Fidji cervical cage fusion were performed for all. The fusion status was evaluated on the basis of X-rays. After surgical intervention, the clinical symptoms improved for all the patients. The disc interspaces in all the patients achieved solid union at final follow-up. Fidji cervical cage is very efficient in achieving cervical fusion in patients with SCIWORA. There are few complications associated with the use of this cage, and the functional and neurological outcomes are satisfactory. [ABSTRACT FROM AUTHOR]