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Ga2O3 has been regarded as a promising material for solar-blind detection due to its ultrawide bandgap and low growth cost. Although semiconductor microwires (MWs) possess unique optical and electronic characteristics, the performances of photodetectors developed from Ga2O3 MWs are still less than satisfactory. Herein, we demonstrate high-performance solar-blind photodetectors based on Sn-doped Ga2O3 MWs, possessing a light/dark current ratio of 107 and a responsivity of 2,409 A/W at 40 V. Moreover, a 1 × 10 solar-blind photodetector linear array is developed based on the Sn-doped Ga2O3 MWs via a patterned-electrodes method. And clear solar-blind images are obtained by using the photodetector array as the imaging unit of a solar-blind imaging system. The results provide a convenient way to construct high-performance solar-blind photodetector arrays based on Ga2O3 MWs, and thus may push forward their future applications. [ABSTRACT FROM AUTHOR]

Large-diameter buried steel pipes (BSPs) play critical roles in water transport for major water diversion and hydropower projects. Due to poor pipe-soil composite system properties and installation conditions, they are prone to excessive deformation, resulting in safety hazards. This paper takes a BSP project subjected to excessive deformation as an example. A simplified numerical model is first established to analyze the structural performance, including the stress and plasticity, and the relationship between the stress and deformation of the pipe. Furthermore, a jacking method to rehabilitate the pipe-soil composite system is conducted to explore its influences on pipe deformation, stress, and plasticity. The results show that considerable bending stresses occur in the pipe and that sections of the midspan and stiffening ring are in the pure bending state and eccentric bending state, respectively. Areas of high stress and plasticity center at the crown, springline, and invert of the pipe, and steel pipes with ring deformation of 8.9% can be continued to be used, as the full yielding of the pipe walls occurs at the ring deformation of 15.8%. The jacking method is an effective solution for the rehabilitation of BSPs subjected to large deformation and can reduce pipe deformation significantly while increasing the stress at the pipe crown and the pipe plasticity only slightly. [ABSTRACT FROM AUTHOR]

Large-diameter buried steel pipes (BSPs) have been widely utilized in water diversion and hydropower fields. This paper presents a comprehensive numerical investigation on the interaction between the large-diameter pipe and soil under three typical working conditions, to capture the structural mechanical behaviors of pipe deformation, soil displacement, and soil pressure. Furthermore, a parametric analysis of pipe diameter is conducted, along with the sensitivity study of soil parameters based on the orthogonal test method. The results show that the water weight increases the pipe deformation significantly by 14%, while the high internal water pressure decreases the deformation greatly with the maximum effect of 39%. The pattern of soil pressure at the top of the pipe changes from parabola to double-hump as the pipe diameter varies from 0.5 m to 5.0 m. The pipe deformation and soil pressure keep increasing with the pipe diameter, but the safety margin for prism load decreases gradually. Pipe deformation and soil pressure are very sensitive to the elastic modulus and Poisson's ratio of backfill. Friction coefficients of soil-soil (trench sidewall) and pipe-soil have great influences on the soil pressure, while the bedding material and backfill cohesion have small effects on it. [ABSTRACT FROM AUTHOR]

The ground support system has a significant impact on tunnel safety while the installation time of initial support is commonly designed by empirical method. The three dimensional numerical model, based on the engineering practice, is analyzed by FLAC3D. In this paper, an improved LDP (longitudinal displacement profile) equation is proposed, which is more accurate in describing the convergence of tunnel before excavation face reaching. Then, a methodology is presented to determine the installation location of initial support in a more efficient and effective way. By simulating the process of excavation load releasing, the appropriate time for installing initial support is when the evolution of surrounding rock displacement has a tendency to increase rapidly, namely that the stability of rock mass arrives at the critical state. The mathematical relationship between the convergence of tunnel and the relative location to tunnel face can be established by fitting monitoring data with the improved LDP equation. Substituting the critical tunnel convergence into the LDP relationship, the corresponding installation location of initial support will be calculated. Meanwhile, several schemes with diverse geological conditions are carried out to validate the improved LDP and the methodology. [ABSTRACT FROM AUTHOR]

The stability of anion exchange membranes (AEMs) is an important feature of alkaline exchange membrane fuel cells (AEMFCs), which has been extensively studied. However it remains a real challenge due to the harsh working condition. Herein, we developed a novel type of polysulfone-based AEMs with three modified 1,2-dimethylbenzimidazoliums containing different substitutes at C4- and C7-position. The results showed that the introduction of the substitutes could obviously improve the dimensional and alkaline stabilities of the corresponding membranes. The swelling ratios of resultant AEMs were all lower than 10% after water immersion. The membrane with 4,7-dimethoxy-1,2-dimethylbenzimidazolium group exhibited the highest alkaline stability. Only 9.2% loss of hydroxide conductivity was observed after treating the membrane in 1 mol·L KOH solution at 80 °C for 336 h. Furthermore, the density functional theory (DFT) study on the three functional group models showed that the substitutes at C4- and C7-position affected the lowest unoccupied molecular orbital (LUMO) energies of the different 1,2-dimethylbenzimidazolium groups. [ABSTRACT FROM AUTHOR]

Pneumatic muscles with similar characteristics to biological muscles have been widely used in robots, and thus are promising drivers for frog inspired robots. However, the application and nonlinearity of the pneumatic system limit the advance. On the basis of the swimming mechanism of the frog, a frog-inspired robot based on pneumatic muscles is developed. To realize the independent tasks by the robot, a pneumatic system with internal chambers, micro air pump, and valves is implemented. The micro pump is used to maintain the pressure difference between the source and exhaust chambers. The pneumatic muscles are controlled by high-speed switch valves which can reduce the robot cost, volume, and mass. A dynamic model of the pneumatic system is established for the simulation to estimate the system, including the chamber, muscle, and pneumatic circuit models. The robot design is verified by the robot swimming experiments and the dynamic model is verified through the experiments and simulations of the pneumatic system. The simulation results are compared to analyze the functions of the source pressure, internal volume of the muscle, and circuit flow rate which is proved the main factor that limits the response of muscle pressure. The proposed research provides the application of the pneumatic muscles in the frog inspired robot and the pneumatic model to study muscle controller. [ABSTRACT FROM AUTHOR]

This paper describes a novel model known as the shadow obstacle model to generate a realistic corner-turning behavior in crowd simulation. The motivation for this model comes from the observation that people tend to choose a safer route rather than a shorter one when turning a corner. To calculate a safer route, an optimization method is proposed to generate the corner-turning rule that maximizes the viewing range for the agents. By combining psychological and physical forces together, a full crowd simulation framework is established to provide a more realistic crowd simulation. We demonstrate that our model produces a more realistic corner-turning behavior by comparison with real data obtained from the experiments. Finally, we perform parameter analysis to show the believability of our model through a series of experiments. [ABSTRACT FROM AUTHOR]

TfoX (Sxy) and CRP are two important competence activators. The link between tfoX and CRP has been shown in H. influenza but lacking evidence of direct interaction. Recently a Sxy-dependent CRP (CRP-S) site autoregulating Sxy was reported in E. coli. Here, we show that the cAMP-CRP complex transcriptionally regulates tfoX expression through multiple canonical CRP (CRP-N) sites in Vibrios. This conclusion is supported by an analysis of the tfoX mRNA levels and tfoX transcriptional reporter fusions. The reduced expression of tfoXVC was restored by trans-complementation of crp in Δcrp and by exogenous cAMP in Δcya. A promoter deletion analysis and the site-directed mutagenesis of the putative CRP-N sites revealed the presence of two functional CRP-N sites. The direct binding of cAMP-CRP to the tfoXVC promoter was demonstrated by EMSA assays. Additionally, the transcriptional start site (TSS) of tfoXVF in V. fluvialis was determined, and -10/-35 regions were predicted. Further comparison of the tfoX promoter in Vibrios revealed the existence of similar -10 motifs and putative CRP-N sites, indicating the conserved mechanism of CRP regulation on tfoX. Our study demonstrates the direct binding of the cAMP-CRP complex to tfoX promoter, and broadens the understanding of the molecular mechanism regulating tfoX in Vibrios. [ABSTRACT FROM AUTHOR]

The aim of this paper was to propose a method of flow rate modulation for simulation of in vivo pharmacokinetic (PK) model with intravenous injection based on a basic in vitro PK model. According to the rule of same relative change rate of concentration per unit time in vivo and in vitro, the equations for flow rate modulation were derived using equation method. Four examples from literature were given to show the application of flow rate modulation in the simulation of PK model of antimicrobial agents in vitro. Then an experiment was performed to confirm the feasibility of flow rate modulation method using levo-ornidazole as an example. The accuracy and precision of PK simulations were evaluated using average relative deviation (ARD), mean error and root mean squared error. In vitro model with constant flow rate could mimic one-compartment model, while the in vitro model with decreasing flow rate could simulate the linear mammillary model with multiple compartments. Zero-order model could be simulated using the in vitro model with elevating flow rate. In vitro PK model with gradually decreasing flow rate reproduced the two-compartment kinetics of levo-ornidazole quite well. The ARD was 0.925 % between in vitro PK parameters and in vivo values. Results suggest that various types of PK model could be simulated using flow rate modulation method without modifying the structure. The method provides uniform settings for the simulation of linear mammillary model and zero-order model based on in vitro one-compartment model, and brings convenience to the pharmacodynamic study. [ABSTRACT FROM AUTHOR]

The essential requirements of the end-effector of large space manipulator are capabilities of misalignment tolerance and soft capture. According to these requirements, an end-effector prototype combining the tendon-sheath transmission system with steel cable snaring mechanism was manufactured. An analysis method based on the coordinate transformation and the projection of key points of the mechanical interface was proposed, and it was a guideline of the end-effector design. Furthermore, the tendon-sheath transmission system was employed in the capture subassembly to reduce the inertia of the capture mechanism and enlarge the capture space. The capabilities of misalignment tolerance and soft capture were validated through the dynamic simulation in ADAMS software. The results of the capture simulation and experiment show that the end-effector has outstanding capabilities of misalignment tolerance and soft capture. The translation misalignments in radial directions are ±100 mm, and angular misalignments about pitch and yaw are ±15°. [ABSTRACT FROM AUTHOR]

In this study, a method of chemical cooling is put forward, that is, C-CO endothermic reaction is applied to instantaneous heat removal under high heat flux. A method in which theoretical research is in combination with numerical simulation is used to study C-CO endothermic reaction. In comparison with the theoretically computational results, numerical code is validated. A high heat flux of 500 W/cm is applied to the research of the heat dissipation characteristics of C-CO endothermic reaction. The theoretical calculation results show that, under a certain temperature and pressure condition, the C-CO chemical endothermic reaction could remove heat from the system promptly; the product CO could be used as a supplementary medium of power source for cycling. Compared with water phase change, the C-CO endothermic reaction appears to have stronger heat removal ability. 'Species Transport' module in FLUENT was adopted to simulate the reaction. Under the same temperature and pressure condition, the numerical simulation results are found to be well congruous with theoretical results. The C-CO endothermic reaction could make a high temperature in the reaction system due to a high heat flux reduce to a low temperature (below zero) promptly. The heat removal and reaction time are in consistence with theoretical calculation. [ABSTRACT FROM AUTHOR]

Emergency exercises are an efficient approach for preventing serious damage and harm, including loss of life and property and a wide range of adverse social effects, during various public emergencies. Among various factors affecting the value of emergency exercises, including their design, development, conduct, evaluation, and improvement planning, this paper emphasizes the focal role of evacuees and their behavior. We address two concerns: What are the intrinsic reasons behind human behavior? How do we model and exhibit human behavior? We review studies investigating the mechanisms of psychological behavior and crowd evacuation animation. A comprehensive analysis of logical patterns of behavior and crowd evacuation is presented first. The interactive effects of information (objective and subjective), psychology (panic, small groups, and conflicting roles), and six kinds of behavior contribute to a more effective understanding of an emergency scene and assist in making scientific decisions. Based on these studies, a wide range of perspectives on crowd formation and evacuation animation models is summarized. Collision avoidance is underlined as a special topic. Finally, this paper highlights some of the technical challenges and key questions to be addressed by future developments in this rapidly developing field. [ABSTRACT FROM AUTHOR]

In order to achieve large tolerance capture and high stiffness connection for space payload operations, a Chinese large-scale space end-effector (EER) was developed. Three flexible steel cables were adopted to capture the payload with large capture allowance. Ball screw transmission mechanism and plane shape-constraint four bar linkage mechanism were utilized to connect the payload with high stiffness. The experiments show that capture tolerances in X, Y, Z, Pitch, Yaw, Roll directions are 100 mm, 100 mm, 120 mm, 10.5°, 10.5°, 12°, respectively. The maximum connection stiffness is 4 800 N·m. The end-effector could meet the requirements for space large tolerance capture and high stiffness connection in the future. [ABSTRACT FROM AUTHOR]

The ability to extract mitochondrial and nuclear DNA from ancient remains has enabled the study of ancient DNA, a legitimate field for over 20 years now. Recently, Y chromosome genotyping has begun to be applied to ancient DNA. The Y chromosome haplogroup in East Asia has since caught the attention of molecular anthropologists, as it is one of the most ethnic-related genetic markers of the region. In this paper, the Y chromosome haplogroup of DNA from ancient East Asians was examined, in order to genetically link them to modern populations. Fifty-six human remains were sampled from five archaeological sites, primarily along the Yangtze River. Strict criteria were followed to eliminate potential contamination. Five SNPs from the Y chromosome were successfully amplified from most of the samples, with at least 62.5% of the samples belonging to the O haplogroup, similar to the frequency for modern East Asian populations. A high frequency of O1 was found in Liangzhu Culture sites around the mouth of the Yangtze River, linking this culture to modern Austronesian and Daic populations. A rare haplogroup, O3d, was found at the Daxi site in the middle reaches of the Yangtze River, indicating that the Daxi people might be the ancestors of modern Hmong-Mien populations, which show only small traces of O3d today. Noticeable genetic segregation was observed among the prehistoric cultures, demonstrating the genetic foundation of the multiple origins of the Chinese Civilization. [ABSTRACT FROM AUTHOR]

Paper, as one of the most important information carriers, has contributed to the development and transmission of human civilization greatly. Meanwhile, a serious problem of environmental sustainable development caused by the production and utilization of paper has been resulted to modern society. Therefore, a simple and green route is urgently demanded to realize rewritable painting on paper. Herein, a simple route to rewritable painting on copy paper has been demonstrated by using eco-friendly ZnO nanoparticles (NPs) as fluorescent ink, and vinegar and soda that are frequently used in kitchen as erasing and neutralizing agents. Words or patterns written using the ZnO NPs as ink can be erased by vinegar vapour within five seconds, and after a neutralizing process in the ambient of soda vapour, the paper can be used for writing again. It is worth noting that the resolution and precision of the patterns produced via the above route degrade little after ten rewriting cycles, and the quality of the patterns produced using the ZnO NPs as ink fades little after being storage for several months, which promises the versatile potential applications of the rewriting route proposed in this paper. [ABSTRACT FROM AUTHOR]

A correction to the article "Numerical Study of a Chemical Method Applied to Instantaneous Heat Removal Under High Heat Flux" in the July 5, 2014 issue is presented.