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Clinical trials have demonstrated the potential neuroprotective effects of uric acid (UA) in Alzheimer's disease (AD). However, the specific mechanism underlying the neuroprotective effect of UA remains unclear. In the present study, we investigated the neuroprotective effect and underlying mechanism of UA in AD mouse models. Various behavioral tests including an elevated plus maze, Barnes maze, and Morris water maze were conducted to evaluate the impact of UA on cognitive function in β-amyloid (Aβ) microinjection and APP23/PS45 double transgenic mice models of AD. Immunohistochemical staining was employed to visualize pathological changes in the brains of AD model mice. Western blotting and immunofluorescence techniques were used to assess levels of autophagy-related proteins and transcription factor EB (TFEB)-related signaling pathways. BV2 cells were used to investigate the association between UA and microglial autophagy. We reported that UA treatment significantly alleviated memory decline in Aβ-induced AD model mice and APP23/PS45 double transgenic AD model mice. Furthermore, UA activated microglia and upregulated the autophagy-related proteins such as LC3II/I ratio, Beclin-1, and LAMP1 in the hippocampus of AD model mice. Similarly, UA protected BV2 cells from Aβ toxicity by upregulating the expressions of Beclin-1, LAMP1, and the LC3II/I ratio, whereas genetic inhibition of TFEB completely abolished these protective effects. Our results indicate that UA may serve as a novel activator of TFEB to induce microglia autophagy and facilitate Aβ degradation, thereby improving cognitive function in AD model mice. Therefore, these findings suggest that UA may be a novel therapeutic agent for AD treatment. [ABSTRACT FROM AUTHOR]

People with mental illness are challenged by self-stigma, leading to a sense of behavioral futility and reduced goal seeking. Honest, Open, Proud (HOP) program is a peer service program that utilizes strategic disclosure to combat self-stigma. HOP was developed and predominantly examined in western culture, leaving unknown its effectiveness in East Asian countries. The current study reports adaptation and evaluation of HOP for Chinese people living with serious mental illness. Adaption underwent a community-based participatory research approach to assure cultural responsiveness. A pilot randomized controlled trial with 135 participants revealed that HOP diminished self-stigma in participants. Satisfaction and feasibility assessments indicated HOP was well received within the focal community. Results suggested HOP had benefits on disclosure self-efficacy and self-stigma for those participating in the program. Future research should further examine cultural mediators of peer support and disclosure on stigma and empowerment. [ABSTRACT FROM AUTHOR]

This paper proposes a new algorithm for detecting and generating simple circuits within a directed graph. Before generating all simple circuits in a directed graph, the algorithm first detects whether there is a simple circuit in directed graph, and the detection can divide the directed graph into trivial graphs or strongly connected components. In the process of detecting the existence of simple circuit, the algorithm repeatedly reduces the number of vertices in vertex set along with edge pruning. Based on depth-first traversal, we can get all simple circuits of the directed graph. Especially, instead of proceeding depth-first traversals based on all vertices, the algorithm starts with a random vertex in a strongly connected component to reduce the number of depth-first traversals, and obtain all simple circuits of this strongly connected component. The difficulty of the algorithm is to detect and delete the repeated circuits in the process of generating all simple circuits, which can reduce both the storage space and time complexity. As a result, the output of the algorithm does not contain any repeated circuits. The algorithm simplifies the edge set of directed graphs and greatly reduces the number of depth-first traversals, thereby reducing the computational complexity and improving the computational efficiency. [ABSTRACT FROM AUTHOR]

The stability of a mobile robot is important because it may tip over. This work proposes a hybrid spray-painting robot with high stiffness for touch-up painting in vehicle repair plant and investigates its stability. The distribution of the center of mass is studied based on the kinematics model, and the static stability of the mobile spray-painting robot is analyzed. A micro element method is proposed to accurately calculate the inertia force and the action point of each link in the robot. Zero-moment point (ZMP) is calculated, and the dynamic stability of the mobile robot is assessed using the ZMP criterion. The smallest reasonable width of AGV is obtained for the lightweight design of the robot. The static and dynamic stabilities of the mobile robot are compared with a traditional series mobile robot with the same workspace. Several case studies are conduct by ADAMS to verify the theoretical analysis. [ABSTRACT FROM AUTHOR]

Among the currently studied nitrogen-doped Pt-C catalysts, the environmental friendliness of the nitrogen source and the stability of Pt-C catalysts for fuel cells are urgent issues to be solved. In this study, nitrogen-doped platinum-based catalyst (CSC/BP-Pt) with excellent stability for the ORR is prepared by a self-doping method based on chitosan (CS), a green biomass material with both nitrogen and carbon sources, in combination with conductive carbon black (BP2000). Finally, the N content of the catalyst is as high as 5.8 wt%, which is higher than most comparable catalysts (3–5 wt%). And electrochemical tests show that the CSC/BP-Pt electrochemical active surface area (ECSA) = 154.1 m2/gPt, half-wave potential (E1/2 = 0.85 VRHE) has a better electrochemical performance than the commercial Pt/C (20 wt%), while the half-wave potential is reduced at 10,000 cycles of cyclic voltammetry with almost no attenuation (only 7 mVcompared to 31 mV of Pt/C). Besides, possible mechanisms to improve the activity and stability of CSC/BP-Pt are preliminarily proposed. [ABSTRACT FROM AUTHOR]

To resist external pressure, stiffened spherical domes have been widely used in underwater vehicles. In traditional design of these thin-walled structures, uniform stiffeners are usually utilized and overly conservative safety factor method is employed to envelop the multi-source uncertainties mainly caused by manufacturing. In this study, a concept of non-uniformly stiffened spherical dome (NUSPD) is developed to improve the structural buckling capacity. Furthermore, an efficient reliability-based design optimization (RBDO) framework is established for NUSPD, which includes a deterministic optimization loop to fix the stiffener layout, and subsequently followed by a RBDO loop to determine the detailed stiffener dimensions and decrease the structural weight under geometric and material property uncertainties. Since the RBDO of stiffened spherical domes is very complex, an improved enhanced chaos control method together with surrogate model is proposed to improve the convergence rate. Finally, the efficiency of the proposed RBDO framework is demonstrated by the NUSPD example. [ABSTRACT FROM AUTHOR]

Batch normalization (BN) enables us to train various deep neural networks faster. However, the training accuracy will be significantly influenced with the decrease of input mini-batch size. To increase the model accuracy, a global mean and variance among all the input batch can be used, nevertheless communication across all devices is required in each BN layer, which reduces the training speed greatly. To address this problem, we propose progressive batch normalization, which can achieve a good balance between model accuracy and efficiency in multiple-GPU training. Experimental results show that our algorithm can obtain significant performance improvement over traditional BN without data synchronization across GPUs, achieving up to 18.4% improvement on training DeepLab for semantic segmentation task across 8 GPUs. [ABSTRACT FROM AUTHOR]

Curved thick beams with smoothly variable cross-section size are very common in practical engineering problems. Designing the variable size based on the traditional finite element methods often leads to non-smooth solutions. To guarantee the smoothness of size distribution, an isogeometric analysis (IGA)-based design approach is proposed in this work to optimize the cross-section size of curved Timoshenko beams for natural frequencies. Due to the geometric exactness and high-order continuity of IGA, there is high accuracy of natural frequency prediction and sensitivity analysis for design optimization. It is found that small numbers of design variables lead to parameterization-dependent solutions, while large numbers of design variables induce design fluctuation. To avoid the undesirable design fluctuation, a stability transformation method-based K-S aggregation constraint scheme is proposed to regularize the size distribution and also achieve the stable convergence of optimal solutions. Multiple design studies including the deterministic and reliability-based optimization problems are performed to demonstrate the applicability and effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Purpose: The present study aims to develop five Gram-negative bacteria expressing bacterial luciferase for use to evaluate the influence of different antibiotics on bacterial bioluminescence.Procedures: The pBBR-lux plasmid was introduced into five Gram-negative bacteria; the bioluminescent signals and colony-forming unit (CFU)/ml of all the bioluminescent strains were monitored with six antibiotics at various concentrations.Results: Dose-dependent bioluminescence signals can be used for rapid bacterial antibiotic susceptibility test (AST). All five bioluminescent bacterial strains have similar bioluminescence and CFU enhancement at sub-minimum inhibitory concentration (MIC) of six different antibiotics.Conclusion: The bioluminescent signals and CFU enhancement at sub-MIC antibiotic concentrations should be of value in the research of new antibiotic drugs and bioluminescent imaging. [ABSTRACT FROM AUTHOR]

Purpose: The goal of this study was to develop a plasmid-based lux bio-reporter for use to obtain in vivo images of Brucella suis vaccine strain 2 (B.suis S2) infection with high resolution and good definition.Procedures: The pBBR-lux (pBBR1MCS-2-lxCDABE) plasmid that carries the luxCDABE operon was introduced into B. suis S2 by electroporation yielding B. suis S2-lux. The spatial and temporal transit of B. suis S2 in mice and guinea pigs was monitored by bioluminescence imaging.Results: The plasmid pBBR-lux is stable in vivo and does not appear to impact the virulence or growth of bacteria. This sensitive luciferase reporter could represent B. suis S2 survival in real time. B. suis S2 mainly colonized the lungs, liver, spleen, and uterus in mice and guinea pigs as demonstrated by bioluminescence imaging.Conclusion: The plasmid-based lux bioreporter strategy can be used to obtain high resolution in vivo images of B. suis S2 infection in mice and guinea pigs. [ABSTRACT FROM AUTHOR]

There are few relevant researches on coils by tempering, and the variations of microstructure and properties of steel coil during the tempering process also remain unclear. By using thermo-mechanical control process(TMCP) technology, Mn-Ti typical HSLA steel coils with yield strength of 920 MPa are produced on the 2250 hot rolling production line. Then, the samples are taken from the coils and tempered at the temperatures of 220 °C, 350 °C, and 620 °C respectively. After tempering the strength, ductility and toughness of samples are tested, and meanwhile microstructures are investigated. Precipitates initially emerge inside the ferrite laths and the density of the dislocation drops. Then, the lath-shaped ferrites begin to gather, and the retained austenite films start to decompose. Finally, the retained austenite films are completely decomposed into coarse and short rod-shape precipitates composed of C and Ti compounds. The yield strength increases with increasing tempering temperature due to the pinning effect of the precipitates, and the dislocation density decreases. The yield strength is highest when the steel is tempered at 220 °C because of pinning of the precipitates to dislocations. The total elongation increases in all samples because of the development of ferrites during tempering. The tensile strength and impact absorbed energy decline because the effect of impeding crack propagation weakens as the retained austenite films completely decompose and the precipitates coarsen. This paper clarifies the influence of different tempering temperatures on phase transformation characteristics and process of Mn-Ti typical multiphase steels, as well as its resulting performance variation rules. [ABSTRACT FROM AUTHOR]

The successful development of safe and highly effective nanoprobes for targeted imaging and simultaneous therapy of in vivo gastric cancer is a great challenge. Herein we reported for the first time that anti-α-subunit of ATP synthase antibody, HAI-178 monoclonal antibody-conjugated fluorescent magnetic nanoparticles, was successfully used for targeted imaging and simultaneous therapy of in vivo gastric cancer. A total of 172 specimens of gastric cancer tissues were collected, and the expression of α-subunit of ATP synthase in gastric cancer tissues was investigated by immunohistochemistry method. Fluorescent magnetic nanoparticles were prepared and conjugated with HAI-178 monoclonal antibody, and the resultant HAI-178 antibody-conjugated fluorescent magnetic nanoparticles (HAI-178-FMNPs) were co-incubated with gastric cancer MGC803 cells and gastric mucous GES-1 cells. Gastric cancer-bearing nude mice models were established, were injected with prepared HAI-178-FMNPs via tail vein, and were imaged by magnetic resonance imaging and small animal fluorescent imaging system. The results showed that the α-subunit of ATP synthase exhibited high expression in 94.7% of the gastric cancer tissues. The prepared HAI-178-FMNPs could target actively MGC803 cells, realized fluorescent imaging and magnetic resonance imaging of in vivo gastric cancer, and actively inhibited growth of gastric cancer cells. In conclusion, HAI-178 antibody-conjugated fluorescent magnetic nanoparticles have a great potential in applications such as targeted imaging and simultaneous therapy of in vivo early gastric cancer cells in the near future. [ABSTRACT FROM AUTHOR]

Based on the optical properties of rare earth fluorescence materials, a set of fluorescence optical fiber systems was designed. The system selects the emitting LED, which is economical and practical as a light source. The experiment of the emission and excitation optical spectrum, decay curve of fluorescence and residuals for several sensitive materials confirms the match of YOS:Eu using the light source and the feasibility of the system. The rare earth material YOS:Eu is selected as the material candidate for being the most sensitive. [ABSTRACT FROM AUTHOR]

To establish the method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in nasopharyngeal carcinoma (NPC) tissues. The total RNA was extracted from NPC cell line CNE-2 and tissues with Trizol and then been transcribed reversely to cDNA, a method of real time fluorescence quantitative RT-PCR for detecting the expression of Survivin mRNA in NPC tissues had been established, in which chronic nasopharyngitis patients’ nasopharynx tissues treated as control group. The expression of Survivin mRNA all could be detected either in CNE-2 cells, NPC tissues or in chronic nasopharyngitis patients’ nasopharynx tissues, and there was higher the expression level of Survivin mRNA in NPC tissues than which in chronic nasopharyngitis patients’ nasopharynx tissues, the difference was significant ( P < 0.01). The expression of Survivin mRNA could be detected both in stage I + II and stage III + IV NPC, and there was no significant difference in relative quantifications of gene expression between these two groups ( P > 0.05). There was no relationship between Survivin mRNA expression and age and sex of NPC patients ( P > 0.05). Real time fluorescence quantitative RT-PCR is a rapid, effective and high sensitive method for detecting the expression of Survivin mRNA in NPC tissues. The overexpression of Survivin mRNA may play some roles in pathogenesis of NPC. [ABSTRACT FROM AUTHOR]

The influence of growth pressure of GaN buffer layer on the properties of MOCVD GaN on α-Al2O3 has been investigated with the aid of a home-made in situ laser reflectometry measurement system. The results obtained with in situ measurements and scanning electron microscope show that with the increase in deposition pressure of buffer layer, the nuclei increase in size, which roughens the surface, and delays the coalescence of GaN nuclei. The optical and crystalline quality of GaN epilayer was improved when buffer layer was deposited at high pressure. [ABSTRACT FROM AUTHOR]

In this paper we propose a new method for measuring the thickness of the GaN epilayer, by using the ratio of the integrated intensity of the GaN epilayer X-ray diffraction peaks to that of the sapphire substrate ones. This ratio shows a linear dependence on the GaN epilayer thickness up to 2 μm. The new method is more accurate and convenient than those of using the relationship between the integrated intensity of GaN epilayer diffraction peaks and the GaN thickness. Besides, it can eliminate the absorption effect of the GaN epilayer. [ABSTRACT FROM AUTHOR]

On the basis of integrated intensity of rocking curves, the multiplicity factor and the diffraction geometry factor for single crystal X-ray diffraction (XRD) analysis were proposed and a general formula for calculating the content of mixed phases was obtained. With a multifunction four-circle X-ray double-crystal diffractometer, pole figures of cubic (002), 1111 and hexagonal 1010 and reciprocal space mapping were measured to investigate the distributive character of mixed phases and to obtain their multiplicity factors and diffraction geometry factors. The contents of cubic twins and hexagonal inclusions were calculated by the integrated intensities of rocking curves of cubic (002), cubic twin 111, hexagonal 1010 and 1011. [ABSTRACT FROM AUTHOR]

The annealing behavior of the hexagonal phase content in cubic GaN (c-GaN) thin Films grown on GaAs (001) by MOCVD is reported. C-GaN thin films are grown on GaAs (001) substrates by metalorganic chemical vapor deposition (MOCVD). High temperature annealing is employed to treat the as-grown c-GaN thin films. The characterization of the c-GaN films is investigated by photoluminescence (PL) and Raman scattering spectroscopy. The change conditions of the hexagonal phase content in the metastable c-GaN are reported. There is a boundary layer existing in the c-GaN/GaAs film. When being annealed at high temperature, the intensity of the T0B and LOB phonon modes from the boundary layer weakens while that of the E2 phonon mode from the hexagonal phase increases. The content change of hexagonal phase has closer relationship with annealing temperature than with annealing time period. [ABSTRACT FROM AUTHOR]

A set of theories and methods has long been needed to enhance geological prospecting. Since 1982, we have been predicting mineral-resource potential based on geological research in China, using a comprehensive information theory and method (CIM), developed to identify mineral-resource domains. The key features of CIM are: (1) to establih comprehensive prospecting models on various scales on the basis of a metallogenic model; the prospecting models are statistical in nature and incorporate a range of 'ore' indicators, (2) to compile detailed metallogenic maps that reflect metallogenic regularities, ore-controlling factors, prospecting indicators, and the positions of favorable target areas, and (3) to establish statistical prediction models of undiscovered mineral resources. This CIM method has been effective and has provided significant economic benefits in the past few years in China. [ABSTRACT FROM AUTHOR]

An asymmetrically coupled (GaAs/AlAs/GaAs/AlAs)/GaAs (001) double-well supperlattice is studied by HRDCD (high resolution double-crystal X-ray diffractometry). The intensity of satellite peaks is modulated by wave packet of different sublayers. In the course of simulation, the satellite peaks in the vicinity of the node points of wave packet are very informative for precise determination of sublayer thickness and for improving accuracy. [ABSTRACT FROM AUTHOR]

Properties of GaAs single crystals grown at low temperatures by molecular beam epitaxy (LTMBE GaAs) have been studied. The results show that excessive arsenic atoms of about 1020 cm−3 exist in LTMBE GaAs in the form of arsenic interstitial couples, and cause the dilation in lattice parameter of LTMBE GaAs. The arsenic interstitial couples will be decomposed, and the excessive arsenic atoms will precipitate during the annealing above 300°C. Arsenic precipitates accumulate in the junctions of epilayers with the increase in the temperature of annealing. The depletion regions caused by arsenic precipitates overlap each other in LTMBE GaAs, taking on the character of high resistivity, and the effects of backgating or sidegating are effectively restrained. [ABSTRACT FROM AUTHOR]

A series of GaAs/InAs/GaAs samples were studied by double crystal X-ray diffraction and the X-ray dynamic theory was used to analyze the X-ray diffraction results. As the thickness of InAs layer exceeds 1.7 monolayer, 3-dimensional InAs islands appear. Pendellosung fringes shifted. A multilayer structure model is proposed to describe the strain status in the InAs islands of the sample and a good agreement is obtained between the experimental and theoretical curves. [ABSTRACT FROM AUTHOR]

Ferromagnetism can occur in wide-band gap semiconductors as well as in carbon-based materials when specific defects are introduced. It is thus desirable to establish a direct relation between the defects and the resulting ferromagnetism. Here, we contribute to revealing the origin of defect-induced ferromagnetism using SiC as a prototypical example. We show that the long-range ferromagnetic coupling can be attributed to the p electrons of the nearest-neighbor carbon atoms around the VSiVC divacancies. Thus, the ferromagnetism is traced down to its microscopic electronic origin. [ABSTRACT FROM AUTHOR]

The clear understanding of exchange interactions between magnetic ions in substituted BiFeO3 is the prerequisite for the comprehensive studies on magnetic properties. BiFe0.5Mn0.5O3 films and BiFeO3/BiMnO3 superlattices have been fabricated by pulsed laser deposition on (001) SrTiO3 substrates. Using piezoresponse force microscopy (PFM), the ferroelectricity at room temperature has been inferred from the observation of PFM hysteresis loops and electrical writing of ferroelectric domains for both samples. Spin glass behavior has been observed in both samples by temperature dependent magnetization curves and decay of thermo-remnant magnetization with time. The magnetic ordering has been studied by X-ray magnetic circular dichroism measurements, and Fe-O-Mn interaction has been confirmed to be antiferromagnetic (AF). The observed spin glass in BiFe0.5Mn0.5O3 films has been attributed to cluster spin glass due to Mn-rich ferromagnetic (FM) clusters in AF matrix, while spin glass in BiFeO3/BiMnO3 superlattices is due to competition between AF Fe-O-Fe, AF Fe-O-Mn and FM Mn-O-Mn interactions in the well ordered square lattice with two Fe ions in BiFeO3 layer and two Mn ions in BiMnO3 layer at interfaces. [ABSTRACT FROM AUTHOR]