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In the reliability analysis of slope stability, the deterministic analysis method is usually used to calculate the safety factor to evaluate the stability of slope. However, the inherent spatial variability of rock mass properties cannot be considered and described adequately in traditional deterministic method, resulting in the inaccurate calculation of slope failure probability. Based on Hoek-Brown criterion and random finite difference method (RFDM), the reliability analysis of slope stability and random response of pile are discussed in this paper considering spatial variability of rock mass. The uniaxial compressive strength σci and material constant for the intact rock mi are regarded as random field variables and geological strength index GSI is assumed to be a random variable. The results show that the spatial variability of rock mass parameters has a significant effect on slope failure probability and pile response. Ignoring the spatial variability of rock mass parameters will overestimate slope failure probability and the mean value of the maximum bending moment of anti-slide pile, and underestimate the mean value of displacement at pile head. The results can provide design guidance for slope reinforcement as well as layout optimization of anti-sliding piles.

By evaluating the results of treating quinoa with different microwave conditions,this paper compares the effects of microwave heating and traditional conduction heating (water bath and baking) on lipase and flavor components of quinoa.Experiments results show that with the increase of microwave power and the extension of treatment time,the activity of lipase decreased significantly.After heating at 600 W power for 4 min,the lipase activity tended to be stable.Through analyzing flavor components in quinoa,we found microwave treatment dramatically reduced the levels of Methyl Ketone,1-octen-3-ol and trans-2-Nonenal.Moreover,with the extension of storage time,the oxidation of oil in quinoa was inhibited by microwave,with the peroxide value and acid value of quinoa decreased.Compared with the traditional heating methods,microwave heating can significantly reduce the activity of lipase in quinoa,and improve the flavor and organoleptic attribute of quinoa milk.

Storage and transportation are one of the primary restrictions on the approach involving hydrogen energy. The traditional hydrogen storage methods, including high-pressure gas cylinder and cryogenic liquid tank show unfavorable economy, thus hindering their further industrial application and development. Metal hydrides can reversibly react with hydrogen and accomplish the hydriding/dehydriding process under mild operation conditions, which feature advantages such as large hydrogen storage amount, low operation pressure and energy consumption. This process is expected to replace the conventional hydrogen storage and transportation. Meanwhile, considering the strong endothermal/exothermic effect during hydrogenation/dehydrogenation, the prompt heat removal/support inside the metal hydride reactor is a key parameter for H2 absorption/desorption rate and H2 storage efficiency. To improve the heat transfer and absorption/desorption rates of metal hydride reactor, comprehensive analysis and evaluation were conducted. Based on the heat and mass transfer intensification, a new elliptical spiral mini-tube bundle reactor (ESMBR) with high efficiency was designed and proposed; the reactor possesses numerous features, such as high heat transfer speed, compact structure, high reaction rate, and convenient operation. All the hydrogen storage reactor models were established, and both the model accuracy and effectiveness were experimentally validated. Numerical simulations of ESMBR, spiral mini-tube bundle reactor, and mini-tube bundle reactor were calculated and compared by COMSOL. ESMBR was proven to exhibit favorable heat and mass transfer performance during the H2 storage. Results of further analysis indicate that the sensitivity order of elliptical spiral structure parameters as follows: Dc > A > B > Pt > α. A multi-element valued model was used to evaluate the reactor schemes systematically, and the calculation results show the integrated superiority of ESMBR could achieve a value of 0.845. The comparison results indicate that the ESMBR presents an outstanding performance compared with other reactors and features a broad application prospect in the field of hydrogen energy.

Torsional vibrations are unavoidable in beam-type structures in various engineering practices, and the advent of metamaterials provides a solution through the generation of bandgaps. However, unlike their flexural counterparts, tunable torsional bandgaps are seldomly studied due to two major difficulties: the existing metamaterial's units are less torsional-sensitive and the reliable torsional sensing techniques for validations are less available. In this work, switchable torsional bandgaps are realized in a metamaterial beam with a bistable resonator design based on Kresling origami with attached eccentric balls. We find that, through compression–torsion interaction of the proposed origami resonators and the corresponding wave-coupling phenomenon, torsional bandgaps can be generated and efficiently tuned, which leads to lower and wider vibration isolation frequency zones. Thanks to bistability, Kresling resonators arranged with eccentric balls can achieve bandgap switching. Specifically, based on the compression–torsion interaction of the bistable Kresling origami, wave coupling will be weakened/enhanced when the Kresling resonators arranged with eccentric balls turn from the 1st/2nd state to the 2nd/1st state, and, thus, the switching of torsional bandgaps can be realized. In order to experimentally validate the tunable torsional bandgaps, a high-sensitive fiber Bragg grating (FBG) displacement sensing system containing two parallel FBG sensors is set up to extract the torsional responses. This research will be helpful for future studies focusing on regulating torsional waves through compression–torsion interaction and mode conversion utilizing wave coupling. [ABSTRACT FROM AUTHOR]

Precise and accurate determination of major components in alkali silicate glasses provides critical information concerning element distribution, petrogenesis and magmatic evolution. However, as one of the most important in situ microanalytical technologies, the application of electron probe microanalysis (EPMA) was limited by the time-dependent loss of X-ray intensity of alkali ions (especially Na) during electron beam bombardment on alkali silicate glasses. In this study, an optimized analytical method was developed using a JEOL JXA 8100 EPMA, aiming to get a long enough incubation duration suitable for accurate analysis of major element mass fractions. The optimal analytical conditions were determined as follows: 15 kV accelerating voltage, 2 nA beam current, 20 μm beam diameter, 40 s peak counting time, Na and K analyzed with top priority, time-saving mode with no additional detector movement and no peak search functioned. The availability of this low beam current density condition (6.37 × 10−3 nA μm−2) to 24 anhydrous reference glasses, with their compositions covering the entire spectrum from the ultramafic to highly siliceous range, was verified by the good agreement of the EPMA measured data with their GeoReM preferred values. Similarly, the methodology presented here is also suitable for analysis of hydrous glasses with H2O contents up to approximately 9 wt%, accompanied by no obvious Na loss found and no complicated mathematical corrections needed, and therefore can be used for the estimation of H2O contents in H2O-rich (>1 wt%) geological glasses by the difference method. Despite its analytical accuracy and precision (>0.5 wt%) not better than those of SIMS and FTIR, EPMA can be used as a substitute technique for H2O determination with its main advantages of excellent spatial resolution (down to 5–10 μm) and analytical convenience, especially for small melt inclusions or tiny experimental quench products, and the case with no appropriate calibration standards or no reported extinction coefficients available for those compositions of interest. In daily application, our optimized method is low cost and easy to implement and can achieve comparable precision and detection limits with acceptable efficiency (∼4–5 min/point for ten major elements) relative to routine analysis conditions. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD), the most common cause of dementia, is a chronic neurodegenerative disease induced by multiple factors. The high incidence and the aging of the global population make it a growing global health concern with huge implications for individuals and society. The clinical manifestations are progressive cognitive dysfunction and lack of behavioral ability, which not only seriously affect the health and quality of life of the elderly, but also bring a heavy burden to the family and society. Unfortunately, almost all the drugs targeting the classical pathogenesis have not achieved satisfactory clinical effects in the past two decades. Therefore, the present review provides more novel ideas on the complex pathophysiological mechanisms of AD, including classical pathogenesis and a variety of possible pathogenesis that have been proposed in recent years. It will be helpful to find out the key target and the effect pathway of potential drugs and mechanisms for the prevention and treatment of AD. In addition, the common animal models in AD research are outlined and we examine their prospect for the future. Finally, Phase I, II, III, and IV randomized clinical trials or on the market of drugs for AD treatment were searched in online databases (Drug Bank Online 5.0, the U.S. National Library of Medicine, and Alzforum). Therefore, this review may also provide useful information in the research and development of new AD-based drugs. [ABSTRACT FROM AUTHOR]

Panax ginseng, an essential component of traditional medicine and often referred to as the king of herbs, has played a pivotal role in medicine globally for several millennia. Previously, traditional phytochemical methods were mainly used for quality evaluation and pharmacological mechanism studies of ginseng, resulting in the lack of systematicness and innovation and hindering the development and utilization of ginseng resources. Since the beginning of the new century, systems biology technology represented by metabolomics has shown unique advantages in the modernization and internationalization of herbal medicine, establishing a bridge for communication between traditional medicine and modern medicine. P. ginseng, a special herb used in medicine and food, is one of the main research objects for qualitative and quantitative analysis of metabolomics and has gradually become the focus of researchers globally. Here, we conducted a comprehensive summary and analysis of numerous studies published in ginseng metabolomics. This review aims to provide more novel ideas for the quality evaluation, development, and clinical application of ginseng in the future and offer more useful technical references for the modernization and internationalization of herbal medicine based on metabolomics. [ABSTRACT FROM AUTHOR]

To enable the space manipulator to complete the original task efficiently after any single joint fails, a fault-tolerant path planning method for the manipulator with single joint failure is proposed based on dexterity space in this paper. On the base of solving the degraded workspace, the dexterity space of the manipulator with single joint failure is established by constructing the dexterity index, and then the traditional A* algorithm is improved to complete fault-tolerant path planning in the dexterity space. The correctness and validity of fault-tolerant path planning based on improved A* algorithm are verified by simulating experiments with 7R manipulator.

This paper proposes a coordinated hybrid force/position control strategy of robonaut performing object transfer operation. Firstly, the constraint relationships between robonaut and object are presented. Base on them, the unified dynamic model of the robonaut and object is established to design the hybrid force/position control method. The movement, the internal force and the external constraint force of the object are considered as the control targets of the control system. Finally, a MATLAB simulation of the robonaut performing object transfer task verifies the correctness and effectiveness of the proposed method. The results show that all the targets can be control accurately by using the method proposed in this paper. The presented control method can control both internal and external forces while maintaining control accuracy, which is a common control strategy.