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Background: Automated surgical workflow recognition is the foundation for computational models of medical knowledge to interpret surgical procedures. The fine-grained segmentation of the surgical process and the improvement of the accuracy of surgical workflow recognition facilitate the realization of autonomous robotic surgery. This study aimed to construct a multigranularity temporal annotation dataset of the standardized robotic left lateral sectionectomy (RLLS) and develop a deep learning-based automated model for multilevel overall and effective surgical workflow recognition. Methods: From December 2016 to May 2019, 45 cases of RLLS videos were enrolled in our dataset. All frames of RLLS videos in this study are labeled with temporal annotations. The authors defined those activities that truly contribute to the surgery as effective frames, while other activities are labeled as under-effective frames. Effective frames of all RLLS videos are annotated with three hierarchical levels of 4 steps, 12 tasks, and 26 activities. A hybrid deep learning model were used for surgical workflow recognition of steps, tasks, activities, and under-effective frames. Moreover, the authors also carried out multilevel effective surgical workflow recognition after removing under-effective frames. Results: The dataset comprises 4 383 516 annotated RLLS video frames with multilevel annotation, of which 2 418 468 frames are effective. The overall accuracies of automated recognition for Steps, Tasks, Activities, and under-effective frames are 0.82, 0.80, 0.79, and 0.85, respectively, with corresponding precision values of 0.81, 0.76, 0.60, and 0.85. In multilevel effective surgical workflow recognition, the overall accuracies were increased to 0.96, 0.88, and 0.82 for Steps, Tasks, and Activities, respectively, while the precision values were increased to 0.95, 0.80, and 0.68. Conclusion: In this study, the authors created a dataset of 45 RLLS cases with multilevel annotations and developed a hybrid deep learning model for surgical workflow recognition. The authors demonstrated a fairly higher accuracy in multilevel effective surgical workflow recognition when under-effective frames were removed. Our research could be helpful in the development of autonomous robotic surgery. [ABSTRACT FROM AUTHOR]

Personal education information can be obtained online, which is convenient for inquiries, but at the same time brings the threat of privacy leakage. At present, everyone's education information is managed by a centralized organization. Centralized management has some security and privacy risks. Once the central management agency has a security problem, it may lead to the disclosure of everyone's per sonal information. Therefore, a privacy protection scheme for personal education information based on attribute-based encryption and homomorphic encryption on blockchain is proposed. Blockchain is a decentralized system and its anti-tampering features are very suitable for protecting data security. In addition, an attribute-based encryption method that performs fine-grained access control to the data content is proposed, which can decrypt the corresponding content according to the attributes held by the user. The use of homomorphic encryption can provide the required query results without knowing the plaintext. Access control, as well as key management, is implemented on Ethereum with smart contracts. Finally, security analysis and an example of privacy protection of personal education information are presented, and time performance is analyzed. [ABSTRACT FROM AUTHOR]

• We achieved hyperbolic metasurfaces by patterning periodically rectangular-groove array on hBN perpendicular to the optical axis and the surface.Due to the existence of the hyperbolic metasurface, a unique double reflection effect occurs on the surface, resulting in asymmetrical reflectivity of different spin components. • We theoretically and numerically analyzed the spatial and angular spin splitting of reflected vortex beams and investigated their correlation. The contribution of angular spin splitting predominated. • In the vicinity of certain singularities, the reflectivity of a spin component approached to zero, resulting in a significant spin splitting and a transition from linear to circular polarization. • In this work, parameters such as intrinsic orbital angular momentum, beam waist, and grating ratio can significantly control the magnitude and direction of spin splitting. This paper investigated the spin splitting of the reflected beam with a vortex beam irradiating on a hyperbolic metasurface. This metasurface structure is the periodically rectangular-groove array on the surface of a hyperbolic crystal with the optical axis normal to its surface, where the array is a sub-wavelength biaxially hyperbolic grating with its periodical direction situated in the surface plane. Based on the hexagonal nitride boron crystal, we theoretically and numerically analyzed the spatial and angular spin splittings of the reflected beam, containing those produced by the transverse and longitudinal shifts. We found that the spatial shifts or spin splitting can be obtained in the first-order approximation of beam deflection, but the angular shifts can be described in the second-order approximation so that it enormously varies with the beam waist. Due to the hyperbolic anisotropy of the metasurface and the intrinsic orbital angular momentum in the incident beam, the expressions of spatial and angular shifts are effectively modified, and a unique double reflection effect occurs on the surface. Near certain reflective intensity distribution singularities, extremely asymmetrical spin splitting can be observed. These shifts and spin splitting can be tuned by varying the orientation of the incident plane and the angle of incidence. [ABSTRACT FROM AUTHOR]

In this paper, the joint connection of epoxy resin concrete truss structure is analyzed by computer simulation and ABAQUS finite element simulation. Figureon software is a set of powerful finite element software for engineering simulation that can solve problems ranging from relatively simple linear analysis to many complex nonlinear problems. It can analyze complex solid mechanics and structural mechanics systems, and it can especially handle very large and complex problems and simulate highly nonlinear problems. Fabricated joints are required for truss structure joints because the construction technology and the stress state of the truss structure are relatively complex. Through modeling multiple groups of joint models, the technical difficulties in establishing finite element models, the determination of grid division and boundary conditions, and the finite element analysis and result comparison of truss joints under various parameters are solved. [ABSTRACT FROM AUTHOR]

With the wide application of computer systems in various fields, the complexity and importance of the software system are increasing. It is difficult to develop a dependable software system. In this paper, we use the system dynamics (SD) simulation method to simulate the global software development (GSD) process, which is used to help project teams control the degree of temporal dispersion and geographical dispersion in the software development process. If it is properly controlled, more dependable software can be developed. First, a simulation modeling framework for the GSD process is proposed. Then, the SD simulation subsystem models for GSD are built and tested. Finally, through the simulation analysis of the Apache Hadoop and Ambari project, we summarize the impact of temporal and geographical dispersions on the quality and schedule of global software development projects. The feasibility of the simulation model is also verified. [ABSTRACT FROM AUTHOR]

This article presents a series of experimental investigations assuming the strut-and-tie model (STM) for anchorage zones in posttensioned concrete structures. The test design for concrete samples is based on finite element analysis for a prestressing process. For end anchorage specimens, the relative location of the reinforcement centroid with respect to the bursting force center was investigated. The test results indicate that the specimen with the coincident reinforcement centroid shows the best performance in resisting the tension load. The presence of spiral reinforcement in the region below the bearing plate results in a redistribution of internal stresses in the anchorage zone. Therefore, Mörsch's model should be refined by moving the STM configuration down by a distance of a quarter of the anchor size. For the interior anchorage zone, the test results confirm that the modified International Federation for Prestressing model offers a safe but economical STM scheme for the interior anchorage zone. [ABSTRACT FROM AUTHOR]

With the advancement of information and communication technologies, technology-supported peer assessment has been increasingly adopted in education recently. This study systematically reviewed 134 technology-supported peer assessment studies published between 2006 and 2017 using a developed analysis framework based on activity theory. The results found that most peer assessment activities were implemented in social science and higher education in the past 12 years. Acting assignments such as performance, oral presentations, or speaking were the least common type of assignments assessed across the studies reviewed. In addition, most studies conducted peer assessment anonymously and assessors and assessees were randomly assigned. However, most studies implemented only one round of peer assessment and did not provide rewards for assessors. Across studies, it was more often the case that students received unstructured feedback from their peers than structured feedback. Noticeably, collaborative peer assessment did not receive enough attention in the past 12 years. Regarding the peer assessment tools, there were more studies that adopted general learning management systems for peer assessment than studies that used dedicated peer assessment tools. However, most tools used within these studies only provide basic functionalities without scaffolding. Furthermore, the results of cross analysis reveal that there are significant relationships between learning domains and anonymity as well as learning domains and assessment durations. Significant relationships also exist between assignment types and learning domains as well as assignment types and assessment durations. [ABSTRACT FROM AUTHOR]

• We present a theoretical study on hybrid-polarization surface magnon polaritons at the oblique surface of antiferromagnet (AF) in an external magnetic field pointed along the AF easy axis, where the easy axis does not lie in the AF surface.Two specific geometries are mainly discussed, the main results and highlights as shown by: • In geometry-I, where the direction of propagation is vertical to the easy axis, we found two hybrid-polarization surface polaritons (HSPs), which are highly nonreciprocal. They are one ordinary hybrid-polarization surface polariton (called a HSP still) and one ghost surface polariton (GSP-I). • In Geometry-II with the easy axis in the propagation plane, we predicted another ghost surface polariton (GSP-II). GSP-II is a TE surface wave and is reciprocal. • One difference between the two GSPs is that the Poynting vector of GSP-I is of oscillation-attenuation and is either positive or negative in the AF, but that of GSP-II monotonously decays with the distance from the surface and is always positive. • Another difference between the two GSPs is that GSP-I can exist not only inside but also outside the AF reststrahlen frequency bands and originates from the external magnetic field. GSP-II exists only in the reststrahlen band without external magnetic field. We investigated hybrid-polarization surface magnon polaritons at the oblique surface of antiferromagnet (AF) in an external magnetic field pointed along the AF easy axis, where the easy axis does not lie in the AF surface. According to the direction of surface-polariton propagation, there are two specific geometries. In geometry-I, where the direction of propagation is vertical to the easy axis, we found two hybrid-polarization surface polaritons (HSPs), which are highly nonreciprocal. They are one ordinary hybrid-polarization surface polariton (called a HSP still) and one ghost surface polariton (GSP-I). GSP-I can exist not only inside but also outside the AF reststrahlen frequency bands and originates from the external magnetic field. In Geometry-II with the easy axis in the propagation plane, we predicted another ghost surface polariton (GSP-II). GSP-II is a TE surface wave and is reciprocal. Another difference between the two GSPs is that the Poynting vector of GSP-I is of oscillation-attenuation but that of GSP-II monotonously decays with the distance from the surface and GSP-II exists only in the reststrahlen band without external magnetic field. This study further enlarges the family of surface polariton and widens the window of polariton application. [ABSTRACT FROM AUTHOR]

Introduction: Endoscopic sinus surgery (ESS) has had many complications, e.g., synechia formation. This meta-analysis investigated the effect of a novel chitosan-based dressing on prevention of synechia and wound healing after ESS. Methods: We systematically searched various medical literature data bases and included the randomized controlled trials (RCT) regarding the effect of novel chitosan-based dressing on ESS. The study outcomes included synechia, granulations, hemostasis, crusting scores, and infection. Results: Six RCTs, which involved 337 patients, were included in the meta-analysis. Compared with control intervention after ESS, chitosan-based gel dressing substantially inhibited synechia (risk ratio [RR] 0.28 [95% confidence interval {CI}, 0.15-0.54]; p = 0.0001), improved granulations (RR 1.47 [95% CI, 1.07-2.03]; p = 0.02), and hemostasis (RR 1.47 [95% CI, 1.07-2.03]; p = 0.02) but demonstrated no effect on crusting scores (standard mean difference -0.41 [95% CI, -1.06 to 0.23]; p = 0.21) and infection (RR 0.88 [95% CI, 0.51-1.52]; p = 0.64). Conclusion: Compared with control intervention, chitosan-based dressing was associated with significantly reduced synechia and with increased granulations and hemostasis but showed no influence on crusting and infection after ESS. [ABSTRACT FROM AUTHOR]

In this paper, we review the background and the recent development of the swimming pool-type low temperature heating reactor (SPLTHR). Particularly, we introduce the recent progress on the research of the technical feasibility, the economy, and the safety of the SPLTHR. Our conclusion suggests that the SPLTHR is mature in technique and competitive in economy. Moreover, it has an excellent inherent safety. We also propose a plan for the industry development of the SPLTHR. [ABSTRACT FROM AUTHOR]

Multiscale models of ion transport in porous media relate microscopic material properties (e.g., pore size distribution and pore connectivity) to their macroscopic counterparts (e.g., porosity, effective diffusion coefficient and effective electrical conductivity). We derive a macroscopic model of ion transport in electrically charged nanoporous materials, and the corresponding effective diffusion coefficient, electric conductivity and transference numbers, that explicitly account for dynamic changes in electrical double layer (EDL) and possible overlap of EDLs in nanopores. The general equations comprising this model reduce to a model of an electrical double layer capacitor (EDLC) used to interpret measurements of the EDLC voltage response to charging. While the original representation relies on empirical coefficients (e.g., Bruggeman's relation), our effective coefficients are derived from the first principles and vary with a range of electrochemical conditions (e.g., initial concentration of ions in the electrolyte). The resulting model predictions of the EDLC voltage response match the experimental data better than the original model does. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the seroprevalence and risk factors of fascioliasis in yaks, Bos grunniens, from 3 counties of Gansu Province in China. A total of 1,584 serum samples, including 974 samples from white yaks from Tianzhu, 464 from black yaks from Maqu, and 146 from black yaks from Luqu County, were collected and analyzed using ELISA to detect IgG antibodies against Fasciola hepatica. The overall F. hepatica seroprevalence was 28.7% (454/1,584), with 29.2% in white yaks (284/974) and 27.9% in black yaks (170/610). The seroprevalence of F. hepatica in yaks from Tianzhu, Luqu, and Maqu was 29.2%, 22.6%, and 29.5%, respectively. Female yaks (30.9%) had higher F. hepatica seroprevalence than male yaks (23.4%). Also, F. hepatica seroprevalence varied by different age group from 24.1% to 33.8%. Further, the seroprevalence ranged from 21.8% to 39.1% over different seasons. Interestingly, the season and age of yaks were associated with F. hepatica infection in yaks in the investigated areas. These findings provided a basis for further studies on this disease in yaks from 3 counties of Gansu Province in northwestern China, which may ultimately support the development of effective control strategies of fascioliasis in these areas. [ABSTRACT FROM AUTHOR]

Objective: To assess the association between maternal active cigarette smoking and the risk of oral clefts in the offspring.Study Design: Oral clefts are divided into three subgroups: total clefts, cleft lip with or without cleft palate (CL ± P), and cleft palate only (CP). Data from studies on different levels of smoking were gathered to examine the dose-response effect.Results: The present meta-analysis included 29 case-control and cohort studies through Cochrane, PubMed, and Ovid Medline searches. A modest but statistically significant association was found between maternal active smoking and CL ± P (odds ratio [OR] 1.368; 95% confidence interval [CI] 1.259-1.486) as well as CP (OR 1.241; 95% CI 1.117-1.378). Half the studies showed positive dose-response effect for each subgroup (test for linear trend, P < .05).Conclusions: There is a moderate risk for having a child with a CL ± P or CP in women who smoke during pregnancy. We could not confirm whether there was a positive dose-response effect between maternal smoking and clefts. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of CeCl3 was investigated in molten AlCl3-NaCl melt with various concentrations of fluoride anions using molybdenum electrode at a temperature of 473 K. Transient electrochemical techniques, such as cyclic voltammetry and square wave voltammetry, were performed to reveal the diffusion coefficients of the electroactive species and reduction steps. Results suggest that there are two steps for Ce(III) ion reduction in molten AlCl3-NaCl: Ce(III)→Ce(II) and Ce(II)→Ce. The reduction processes shifted to Ce(III)→Ce when NaF was added in the melt in increasing amount. The molar ratio of fluoride ions and cerium (F/Ce ratio) was employed as a parameter to illustrate the influence of fluoride anions. The diffusion coefficient of electroactive species were determined in AlCl3-NaCl melt at 473 K by using square wave voltammetry. [ABSTRACT FROM AUTHOR]