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Background This review will assess current evidence related to the effectiveness and safety of acupoint catgut embedding therapy for functional constipation (FC) and provide efficacy assessments for clinical applications. Methods We will search the following databases for relevant trials: PubMed, EMBASE OVID, Cumulative Index of Nursing and Allied Health Literature, OVID MEDLINE, Web of Science, the Cochrane Central Register of Controlled Trials, Cochrane library, and Scopus. We will also search the following Chinese databases for trials published in the Chinese literature: China National Knowledge Infrastructure Database (CNKI), Chinese Scientific Journals Database, Wan Fang Database, Chinese Biomedicine and other resources from inception to December 2020. Only randomized controlled trials comparing acupoint catgut embedding versus acupuncture or sham acupuncture or placebo or other therapies will be included. The outcomes involved mean spontaneous bowel movements, complete spontaneous bowel movements, the Bristol Stool Form Scale, the Cleveland Clinic Score, Patient Assessment of Constipation symptom and so on. The risk of bias assessment and quality of evidence for outcomes will be appraised using the Cochrane Risk of Bias Tool and the Grading of Recommendations, Assessment, Development and Evaluation guidelines. RevMan 5.3 software will be employed for the meta-analysis. Results This work will compare and arrange the comparative efficacy of acupoint catgut embedding with different treatments for FC by summarizing the current evidences. Conclusion The results of this meta-analysis may help doctors determine the best treatments for patients to manage FC. Ethics and dissemination This is a protocol with no patient recruitment and personal information collection, approval by the ethics committee is not required. Osf registration number DOI 10.17605/OSF.IO/XTKE2.

Quantum key distribution (QKD) gradually has become a crucial element of practical secure communication. In different scenarios, the security analysis of genuine QKD systems is complicated. A universal secret key rate calculation method, used for realistic factors such as multiple degrees of freedom encoding, asymmetric protocol structures, equipment flaws, environmental noise, and so on, is still lacking. Based on the correlations of statistical data, we propose a security analysis method without restriction on encoding schemes. This method makes a trade-off between applicability and accuracy, which can effectively analyze various existing QKD systems. We illustrate its ability by analyzing source flaws and a high-dimensional asymmetric protocol. Results imply that our method can give tighter bounds than the Gottesman-Lo-L\"utkenhaus-Preskill (GLLP) analysis and is beneficial to analyze protocols with complex encoding structures. Our work has the potential to become a reference standard for the security analysis of practical QKD.

A destruction test based on the bridge safety appraisal is one way to verify the failure law of an actual bridge. In this paper, a stone arch bridge in a 1:10 scale model and with a span of 60 m (namely, an arch bar of the same length as the object of test) has been tested, methods of its whole test and loading process introduced, and ultimate bearing capacity, deflection and development rules of cracks in the loading process figured out. With the clarification of destruction mechanism, the ultimate forms of disease and remaining height of section have been acquired and, finally, the destruction theory of stone arch bridges has been verified and optimized.

An infrared camera (IR) has been put into operation in the Experimental Advanced Superconducting Tokamak (EAST), which is used to measure the temperature distribution on the surface of lower divertor target plates. With a finite difference method, the heat flux onto the divertor target plates is calculated from the surface temperature profile. The high confinement mode (H-mode) with type-III edge localized modes (ELMs) has been obtained with about 1 MW lower-hybrid wave power on the EAST in the autumn experiment in 2010. The analyzed H-mode discharges were lower single null X-point diverted discharges with a density range of (1 ~ 4) × 1019 m−3. The surface temperature of the inner target plate increases with heating power. The peak temperature on the surface of target plates is lower than 200°C with about 2.4 MW heating power. Comparison among the heat flux profiles occurring in different phases in the same discharge has been performed. It indicates that the heat flux profile obviously changes from the ohmic phase to the H-mode phase, and the full width at half maximum (FWHM) of the heat flux profile is the narrowest during the ELM-free H-phase. On the outer target plate, the peak heat flux exceeds 2 MW/m2 during the ELMy H-mode phase, whereas it is only about 0.8 MW/m2 during the ELM-free phase in the same discharge.

We propose a general and model-free approach for Reinforcement Learning (RL) on real robotics with sparse rewards. We build upon the Deep Deterministic Policy Gradient (DDPG) algorithm to use demonstrations. Both demonstrations and actual interactions are used to fill a replay buffer and the sampling ratio between demonstrations and transitions is automatically tuned via a prioritized replay mechanism. Typically, carefully engineered shaping rewards are required to enable the agents to efficiently explore on high dimensional control problems such as robotics. They are also required for model-based acceleration methods relying on local solvers such as iLQG (e.g. Guided Policy Search and Normalized Advantage Function). The demonstrations replace the need for carefully engineered rewards, and reduce the exploration problem encountered by classical RL approaches in these domains. Demonstrations are collected by a robot kinesthetically force-controlled by a human demonstrator. Results on four simulated insertion tasks show that DDPG from demonstrations out-performs DDPG, and does not require engineered rewards. Finally, we demonstrate the method on a real robotics task consisting of inserting a clip (flexible object) into a rigid object.

We are increasingly surrounded by artificially intelligent technology that takes decisions and executes actions on our behalf. This creates a pressing need for general means to communicate with, instruct and guide artificial agents, with human language the most compelling means for such communication. To achieve this in a scalable fashion, agents must be able to relate language to the world and to actions; that is, their understanding of language must be grounded and embodied. However, learning grounded language is a notoriously challenging problem in artificial intelligence research. Here we present an agent that learns to interpret language in a simulated 3D environment where it is rewarded for the successful execution of written instructions. Trained via a combination of reinforcement and unsupervised learning, and beginning with minimal prior knowledge, the agent learns to relate linguistic symbols to emergent perceptual representations of its physical surroundings and to pertinent sequences of actions. The agent's comprehension of language extends beyond its prior experience, enabling it to apply familiar language to unfamiliar situations and to interpret entirely novel instructions. Moreover, the speed with which this agent learns new words increases as its semantic knowledge grows. This facility for generalising and bootstrapping semantic knowledge indicates the potential of the present approach for reconciling ambiguous natural language with the complexity of the physical world., Comment: 16 pages, 8 figures

A measurement method with calotte cube was proposed to realize the high-precision calibration of size error in industrial computer tomography (CT) system. Using the traceability of calotte cube, the measurement of the repeatability error, probing error and length measurement error of industrial CT system was carried out to increase the acceptance of CT as a metrological method. The main error factors, including the material absorption, projection number and integration time and so on, had been studied in detail. Experimental results show that the proposed measurement method provides a feasible way to measure the size error of industrial CT system. Compared with the measurement results with invar 27- sphere gauge, a high accuracy in the order of microns is realized with the proposed method based on calotte cube. Differing from the invar 27-sphere gauge method, the material particularity of calotte cube (material of metallic titanium) could introduce beam hardening effect, the study on the influence of material absorption and structural specificity on the measurement, which provides significant reference for the measurement of metallic samples, is necessary.

To overcome the accuracy limitation due to the machining error of standard parts in measurement system, a threedimensional coordinate measurement method with subwavelength-aperture-fiber point diffraction interferometer (PDI) is proposed, in which the high-precision measurement standard is obtained from the ideal point-diffracted spherical wavefront instead of standard components. On the basis of the phase distribution demodulated from point-diffraction interference field, high-precision three-dimensional coordinate measurement is realized with numerical iteration optimization algorithm. The subwavelength-aperture fiber is used as point-diffraction source to get precise and highenergy spherical wavefront within high aperture angle range, by which the conflict between diffraction wave angle and energy in traditional PDI can be avoided. Besides, a double-iterative method based on Levenbery-Marquardt algorithm is proposed to realize precise reconstruct three-dimensional coordinate. The analysis shows that the proposed method can reach the measurement precision better than microns within a 200×200×300 (in unit of mm) working volume. This measurement method does not rely on the initial iteration value in numerical coordinate reconstruction, and also has high measurement precision, large measuring range, fast processing speed and preferable anti-noise ability. It is of great practicality for measurement of three-dimensional coordinate and calibration of measurement system.

As a key element in point-diffraction interferometer (PDI), the diffraction pinhole determines the sphericity of the reference wavefront and achievable precision of the testing system. The point-diffraction wavefront error, aperture angle, and light transmittance in the PDI operating at visible light, which are determined by pinhole dimension, are analyzed based on finite difference time domain (FDTD) method. The study shows that an aperture angle about 75° can be obtained with a 1 μm pinhole diameter, and the corresponding testing precision is better than root mean square λ/1000 within 0.35 NA. Both the numerical simulation and experiments have been carried out to demonstrate the feasibility of the proposed analysis approach, and a good agreement is obtained between calculated and measured parameters in visible-light PDI. The proposed simulation approach with the FDTD method provides a feasible way to analyze the diffraction wavefront in visible-light PDI, as well as a powerful tool for the design and optimization of PDI system.

The histochemical changes in mucin at the postoperative resection margins in carcinoma of the upper and middle third of the rectum after anterior resection were studied retrospectively in 52 patients. The sialomucinous change was most likely to occur at the intestinal margins of those patients who had tumour recurrence (P less than 0.001). The histological types of tumour, degree of differentiation, Dukes' stages and their distance from the anal verge were virtually the same in patients with and without tumour recurrence. By using high iron diamine-alcian blue staining technique we identified patients with higher risk conditions of tumour recurrence after anterior resection. This technique should increase the likelihood of a cure for patients with recurrent carcinoma of the rectum after anterior resection.