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Based on the construction practice of the Beijing Metro Line 10 shield tunneling project, this paper describes research on soil improvement technology for Beijing stratum characteristics (sandy gravel stratum) and covers similar engineering conditions. It also describes the development of a new type of mud improver. Based on the laboratory tests with bentonite as the base mud and different additives, the effects of guar gum, CMC, xanthan gum, and clay medium particles on mud performance are analyzed. Then, two kinds of mud were used to conduct indoor simulated muck improvement tests (mixing test, slump test, sliding plate test, and adhesion resistance test), and the improvement effects of new mud and ordinary mud applied in pebble/round gravel and sandy soil layers were compared. The results show that xanthan gum is the best material to improve the performance of slurry, using the contrast test of bentonite-based slurry and different additives. The optimum slurry preparation scheme is 4% bentonite, 0.2% xanthan gum, 0.04% soda ash, and 1% clay particles. Using indoor simulated muck improvement tests (mixing test, slump test, slide plate test, and adhesion resistance test), the improvement effects of applying new mud and ordinary mud in pebble/round gravel and sandy soil layers are compared, and the advantages of the new mud in the application of the above two formations are verified. Among them, the new slurry has great advantages for improving the two parameters of the soil adhesion resistance coefficient and slump during shield tunneling. When the improved soil mass reaches the flowing plastic state, the proportion of new mud added to different soil mass is different. The proportion of new mud added to improved pebble/pebble soil is 28%, and that of sand and clay is 32%. It can be seen that new mud is more suitable for improving pebble/pebble soil.

Background: The Hyphantria cunea is a worldwide quarantine pest. It has the characteristics of a wide variety of recipes, strong adaptability, wide transmission channels and serious harm, which seriously endanger the sustainable development of the ecological environment. At present, the control methods of the Hyphantria cunea are costly and inefficient. Objective: An intelligent target spraying robot based on machine vision is designed for cleansing Hyphantria cunea larva nets according to the characteristics of the net curtain and the background color. Methodology: The mobile mechanism of the spraying robot is based on a crawler type trolley and the three-dimensional movements are achieved by stepping motor and synchronous belt driving linear guide slider in the horizontal plane, and by the lead screw in the vertical direction. The on-board software controls the hand-eye actuator to scan the target trees with a specific trajectory, and performs image processing to identify the target so as to intelligently spray on the target. Results: The spraying robot can cope with the irregular distribution of Hyphantria cunea larva nets, and can realize the three-dimensional movement of the nozzle, and perform the progressive scanning to identify the larva nets, and the robot controls the nozzle to spray the medicine, thereby realizing the intelligent spraying of the target. Conclusion: Experiments show that accurate target spraying of the robot can be achieved, and the target coverage rate can reach up to 85% of the total larva nets, which greatly improves the spraying efficiency.

A low-cost differential mobility spectrometer (DMS) was constructed using polytetrafluoroethylene printed circuit boards with two pairs of gold electrodes. The printed circuit boards were used to c...

Chemical control is the major approach to handle the American Hyphantria cunea issue; however, it often causes chemical pollution and resource waste. How to precisely apply pesticide to reduce pollution and waste has been a difficult problem. The premise of accurate spraying of chemicals is to accurately determine the location of the spray target. In this paper, an algorithm based on a convolutional neural network (CNN) is proposed to locate the screen of American Hyphantria cunea. Specifically, comparing the effect of multicolor space-grouping convolution with that of the same color space-grouping convolution, the better effect of different color space-grouping convolution is first proved. Then, RGB and YIQ are employed to identify American Hyphantria cunea screen. Moreover, a noncoincident sliding window method is proposed to divide the image into multiple candidate boxes to reduce the number of convolutions. That is, the probability of American Hyphantria cunea is determined by grouping convolution in each candidate box, and two thresholds (E and Q) are set. When the probability is higher than E, the candidate box is regarded as excellent; when the probability is lower than Q, the candidate box is regarded as unqualified; when the probability is in between, the candidate box is regarded as qualified. The unqualified candidate box is eliminated, and the qualified candidate box cannot exit the above steps until the number of extractions of the candidate box reaches the set value or there is no qualified candidate box. Finally, all the excellent candidate boxes are fused to obtain the final recognition result. Experiments show that the recognition rate of this method is higher than 96%, and the processing time of a single picture is less than 150 ms.

The authors wish to retract the article. In this article, they found that astrocytes that were pretreated with paeonol significantly rescued MPP+-induced cell viability reduction, and inhibited up-regulation of cell apoptosis, caspase-1 activity, COX2, iNOS, and Bax/Bcl-2 ratio, as well as p-JNK and p-ERK. These findings suggest that paeonol is a neuroprotective agent suitable for use in treatment of PD. However, in subsequent research, they examined the protein levels of p-JNK/p-ERK/p-P38 in different groups. Results showed that in the MPP+ groups, not all these protein levels were higher than those in the control group, because of the flawed data presentations. They also used western blot analysis to assess protein levels of Bax and Bcl-2 in astrocytes. Compared with the control group, Bax protein level was increased, while Bcl-2 protein level was decreased after treatment with MPP+, and these changes were not reversed by paeonol. Based on the above, they ascertained that there must have been some serious mistake in their experiment. As a result, all authors agreed to retract this article. Reference: Maosheng Ye, Yuxin Yi, Shixing Wu, Yong Zhou, Dongji. Role of Paeonol in an Astrocyte Model of Parkinson Disease. Med Sci Monit, 2017; 23: 4740-4748. DOI: 10.12659/MSM.906716.

BACKGROUND To explore the TEM8 expression in patients with lung cancer and its relationship with clinical pathology and prognosis, and to analyze the diagnostic value of TEM8. METHODS A total of 204 patients with lung cancer diagnosed and treated in Zhongmeng Hospital Zhalantun and the First Affiliated Hospital of Jinzhou Medical University from March 2013 to February 2016 were enrolled in the study group, and 203 healthy subjects in the control group. qRT-PCR technique was applied to detect the TEM8 expression. Combined with clinical information, the diagnostic value of TEM8 for lung cancer and the correlation of clinical characteristics of TEM8 were analyzed. The 3-year survival curves of patients with low and high TEM8 expressions were compared. RESULTS The expression in the study group was significantly higher than that in the control group (P

The geochemistry of rare earth elements (REEs) was studied in rock samples from host formations, ore samples from two mineral deposits (the Hetaoping Cu-Pb-Zn mine: HTP and the Heiyanao Fe-Cu-Pb-Zn mine: HYA) and the overlying or nearby soils to better understand REE concentrations, distributions and behaviour during weathering from different parent materials at the regional scale, Baoshan area, Yunnan Province, SW China. The mudstone and sandstone formations have the highest total REE (ΣREE) contents. Chondrite-normalized diagrams for rocks and ores show significant light REEs (LREEs) enrichments and Eu depletion (except for ores in HYA). Cerium displays an obvious negative anomaly in carbonate rocks (Є-3-R, C-R, D-R, T-1-R and T-2-R). Soils overlying carbonate rock formations (T-1-S, C-S and Є-3-S) have the highest ΣREE contents, while soils overlying basalts have the lowest ΣREE contents. Soils show enrichments in LREEs with negative Eu anomalies and slight Ce anomalies in the studied soils. Soils with high ∑LREE/∑heavy REE (HREE) values may result from the preferential absorption of LREEs by organic matter. Negative Eu anomalies in soils occur for parent materials in the study area lacking feldspar, especially soils developed from carbonates. Compared to the parent materials, most soils show REE enrichment because alkali metals are removed and REEs are concentrated by low mobility in surficial processes and positive Ce anomalies because of weathering dissolution of other trivalent REEs with ionic radii similar to that of Ca2+. Supplementary material: Additional data (Tables S1 and S2) and sample locations (Fig. S1) are available at https://doi.org/10.6084/m9.figshare.c.5303140

Figure S1 and Tables S1 and S2

The Yunnan-Guizhou-Guangxi region is well known for its abundant mineral resources, and low-temperature hydrothermal mineralization represented by the elemental association of gold, arsenic, antimony and mercury is widely developed there. Many studies on the geological-geochemical characteristics of gold have been conducted, but a comprehensive understanding of the antimony geochemical pattern is still lacking. This paper studied the Sb distribution characteristics and the cause of geochemical anomalies based on the geochemical data of stream sediments and rocks in the study area. In addition, the geochemical data of Au, As, Sb and Hg were centered and log-ratio transformed to eliminate the closure effect, and then random forest regression (RFR) with Au, As and Hg as the characteristic variables was used to investigate the ore-related geochemical anomalies of Sb. Seven geochemical provinces were delineated from the original geochemical data, and they are not entirely consistent with the known deposits. Sb moves from the rocks to the stream sediments during weathering. The variation trend in the Sb background values in stream sediments in each tectonic unit is consistent with that in the rocks themselves, implying that Sb in the stream sediments is inherited from the background rocks. The distributions of Sb predicted by RFR are similar to the distribution pattern of Sb in stream sediments. Of the three elements considered, the influence of As on the variations in the Sb geochemical background is the greatest, followed by Au and then Hg. The geochemical anomalies extracted by the residuals produced in this algorithm are consistent with where the known Sb metallogenic district is located, indicating that this method of recognizing geochemical anomalies is feasible and effective and has theoretical and practical significance.

One hundred and twenty-eight stream sediment samples were collected in the Misiones province of Argentina by the low-density geochemical mapping project of the China Geological Survey. The analyzed data were used to study the concentration, spatial distribution, local pollution level and potential ecological risk of eight heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb and Zn) by factor analysis, geoaccumulation index (Igeo), enrichment factor (EF) and the Hakanson’s potential ecological risk index (Eir and RI) methods. Results showed that the background values (median) of those elements were 2.97 ppm, 0.13 ppm, 212.60 ppm, 322.53 ppm, 0.013 ppm, 64.42 ppm, 12.58 ppm, and 198.85 ppm, respectively. Except for Hg, the contents of other elements were higher than the abundance of continental crust. The spatial distribution of Cu and Zn in stream sediments were consistent, while that of other elements were different. The factor analysis results implied that Cd, Cr, Cu, Ni and Zn were mainly affected by geological background and inherited the characteristics of regional parent rocks. Furthermore, Pb was not only controlled by natural conditions but also related to human activities, while As and Hg represented the anthropogenic sources, and their concentrations were affected by human activities. The results of Igeo and EF told us that Cu was heavily polluted in stream sediments, Pb and Zn were largely mildly polluted, As, Cr, Cd, Ni and Hg were mostly nonpolluted. The ecological risks were ordered as As &gt, Cu &gt, Cd &gt, Pb &gt, Hg &gt, Cr &gt, Ni &gt, Zn. In general, the potential ecological risk of heavy metals in the Misiones province was low, but As and Cu also have a high ecological risk at some sampling points, which should be considered.

BACKGROUND Parkinson's disease (PD) is characterized by a progressive degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc). Inflammation and neural degeneration are implicated in the pathogenesis of PD. Paeonol has been verified to attenuate inflammation. MATERIAL AND METHODS 1-methyl-4-phenylpyridnium ion (MPP+, 100 μM) was used to induce the cell model of PD in primary cultured astrocytes. Astrocyte cell viability and apoptosis were determined by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay and flow cytometry (FCM), respectively. Protein levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthases (iNOS) in culture medium were tested by enzyme-linked immunosorbent (ELISA) assay. Protein levels of casapse-1, COX2, iNOS, B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), Bcl-2, and phosphorylated Jun N-terminal kinase (p-JNK)/phosphorylated extracellular signal-regulated kinase (p-ERK)/p-P38 were examined by Western blot. RESULTS Pretreatment with paeonol remarkably rescued MPP+-induced cell viability reduction, up-regulation of cell apoptosis, caspase-1 activity, COX-2, iNOS, and Bax/Bcl-2 ratio in primary astrocytes. Furthermore, paeonol repressed MPP+ -induced elevation of p-JNK/p-ERK in primary cultured astrocytes. CONCLUSIONS The present study found that paeonol protected cells from apoptosis by repressing the activation of the JNK/ERK related signalling pathway induced by MPP+ in astrocytes. We propose that paeonol is a neuroprotective agent for the treatment of PD patients, with great promise in the future.

As a famous heuristic algorithm, bat algorithm (BA) simulates the behavior of bat echolocation, which has simple model, fast convergence and distributed characteristics. But it also has some defects like slow convergence and low optimizing accuracy. Facing the shortages above, an optimization bat algorithm based on adaptive speed strategy is proposed. This improved algorithm can simulate the bat in the process of search based on adaptive value size and adaptive speed adjustment. His approach can improve the optimization efficiency and accuracy. Experimental results on CEC2013 test benchmarks show that our proposal has better global searchability and a faster convergence speed, and can effectively overcome the problem convergence.

A grafting robot based on cleft grafting method has been developed to improve efficiency of grafting solanaceae vegetables. This robot consists of four parts including a clamping manipulator and carrying, cutting, feeding mechanisms. These not only enable the robot to conveniently perform clamping, carrying, positioning, cutting, joining, and binding rootstock and scion, but also improve the grafting efficiency. The average success rates for cutting rootstock, cutting scion and conjugation are 98.7%, 99.0% and 59.6% respectively. The developed robot was able to perform steady operations, suggesting potential value for practical applications.

In this paper, a multi-layered terahertz metamaterial has been proposed, which consisted of dual-layered substrate and three 6-shaped meta-layered. Numerical results reveal that the structure realizes broadband asymmetric transmission of linearly polarized wave. In particular, this structure realizes a maximum of 0.95 for asymmetric transmission at 6.7THz. Based on the electric fields, we have analyzed the wave conversion of linearly polarized wave and the mechanism of asymmetric transmission effect.

The target spraying effect of spray robots mainly depends on the control performance of the spraying arm during the processes of aiming and tracking. To further improve the robustness of the endpoint control and positioning accuracy of the spray arm, an improved potential field algorithm for the motion planning and control of the spray arm is proposed based on prophase research. The algorithm introduces a velocity potential field, visual field constraints and joint position limit constraints into the traditional artificial potential field method. The velocity potential field is used to ensure that the target state of the spraying arm is at the same velocity as the target crop (relative velocity) to achieve stable target tracking. The visual field constraints and joint position limit constraints are utilized to ensure the efficiency of the visual servo control and the movement of the spray arm. The algorithm can plan a feasible trajectory for the spraying arm in Cartesian space and image space, and use the speed controller to control the spraying arm movement along the trajectory for aiming and tracking. Simulation analysis shows that the algorithm can plan better motion trajectories than the servo controller based on image moments in previous studies. In addition, the experimental results show that the algorithm can effectively improve the robustness of targeting and tracking control for the spray robot.

At present, detection of football bounce rate on football fields is mainly based on manual method in China, which is labor intensive and has low detection accuracy. To solve this problem, based on the photoelectric sensor arrays, an optical detection method is proposed for measuring football field bounce rate. A football clamping mechanism has been theoretically analyzed and then a simple and reliable football holding device was developed to perform clamping and release. A control system of the football field bounce rate detector has been constructed based on modular design principles. The detector was completed on this basis, which can achieve gripping, lifting, releasing football and bounce rate calculation. Experiments showed that the errors of detection accuracy of this equipment are not more than 1%, fully satisfying the relevant national standards.

In this paper, a novel 5UPS-RPS 5-dof parallel mechanism with five UPS-type active legs and one RPS-type constraint leg is proposed, and its kinematics and statics are studied systematically. First, a prototype of this PM is constructed and the dof of this PM is analyzed. Second, analytic formulas for solving the inverse displacement kinematics are derived. Third, the velocity Jacobian matrix and Hessian matrix are derived and analytic formulas for solving the velocities and accelerations of this PM are derived systematically. Finally, an analytic example is given for solving the length, velocity and acceleration of the active legs.

In this paper, we propose to integrate structural information with appearance features for human action recognition. In local representations based on detected spatio-temporal interest points (STIPs), the layout of STIPs carries important cues of motion structures in video sequences, and is assumed to contain complementary information to appearance features. We aim to incorporate structures into the description of STIPs by combing with appearance features for action representation. Based on the previous work of the 3D shape context, we present an optimised version of 3D shape context to encode the layout information of STIPs. By combining the proposed optimised 3D shape context with appearance descriptors, e.g., HOG3D and 3D gradients, we provide a more informative and discriminative description of STIPs for action classification. To validate the proposed descriptor, we have conducted extensive experiments on the KTH and the UCF YouTube datasets. The results prove that the optimised 3D shape context offers complementary information to appearance features, showing its effectiveness for action representation; moreover, the proposed descriptor yields comparable results with the state-of-the-art methods.

A corona discharge (CD) ionization source was prepared for a planar high-field asymmetric waveform ion mobility spectrometer (FAIMS). The effects of discharge current and discharge distance on ionization efficiency were investigated; and the electric field dependence of the ion injection in the reaction region was studied. The results showed that the discharge current of CD source had good linearity with the intensity of reactant ion peak (RIP), and the RIP intensity increased to a stable level at the discharge distance of >5 mm. An injection electrode was introduced to improve the ionization efficiency. A square-wave voltage applied to the electrode was found to provide optimal performance of ion injection and utilization. The operating parameters of the CD-FAIMS were optimized to achieve trace level detection of dimethyl methylphosphonate (DMMP) sample. The detection limit for DMMP was 0.5 µg/m3.

The aim of the present study was to explore the effect of silencing wild‑type p53‑induced phosphatase 1 (Wip1) on apoptosis of human ovarian cancer SKOV3 cells. SKOV3 cells cultured in vitro were divided into three groups: untreated cells, cells transfected with control small interfering RNA (siRNA) and cells transfected with siRNA targeting Wip1. Flow cytometry analysis was used to detect cell apoptosis. Western blot analysis was performed to determine expression of tumor protein 53 (p53), cleaved caspase‑3, caspase‑3, BCL2 associated X (Bax), BCL2 apoptosis regulator (Bcl‑2), p38 mitogen‑activated protein kinase (p38 MAPK) and phosphorylated (p)‑p38 MAPK. Reverse transcription‑quantitative polymerase chain reaction was used to detect expression of p53, Bax, Bcl‑2 and caspase‑3 mRNAs. Compared with control, apoptosis of SKOV3 cell was significantly increased following Wip1 siRNA silencing. Wip1 silencing also resulted in a significant increase of p53 and p‑p38 MAPK expression, as well as increased cleaved caspase‑3/caspase‑3 and Bax/Bcl‑2 protein ratios. No significant differences were observed in apoptosis and apoptosis‑related protein expression in the control siRNA transfected cells. The present study demonstrated that Wip1 silencing promotes apoptosis of human ovarian cancer SKOV3 cells by activation of the p38 MAPK signaling pathways and through subsequent upregulation of p53, and cleaved caspase‑3/caspase‑3 and Bax/Bcl‑2 protein ratios. Overall, the findings of the present study suggest that targeting Wip1 may be a potential therapeutic avenue for the treatment of human ovarian cancer in the future.