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Objective: To explore the effects of cone beam CT (CBCT)-guided radiotherapy set-up errors on irradiation dose of patients with upper and middle esophageal cancer. Methods: A total of 60 patients with middle and upper esophageal cancer admitted to our hospital from May 2017 to May 2019 were selected as the research subjects. All patients underwent CBCT images and planned CT image acquisition. CBCT scan was performed on patients before radiotherapy, and the CBCT image was matched with the planned CT image to obtain linear errors in three directions of left-right (x-axis), head-to-foot (y-axis) and front-to-back (z-axis), and the errors and distribution of errors were analyzed. The simulated actual irradiation system was used to carry out a simulation plan to obtain the actual irradiation target area and the irradiation dose of normal tissues, and compared it with the pre-treatment plan, and the effects of set-up errors on irradiation dose of patients were studied. Results: The overall set-up error of patients was (2.91± 2.20) mm in x-axis, (3.89± 2.17) mm in y-axis and (2.44± 1.64) mm in z-axis, and the MPTV of x-axis was 4.054 mm, and MPTV of y-axis was 8.183 mm and MPTV of z-axis was 3.482 mm. The Dmin, Dmean and D95% of CI and PTV of the simulation plan were significantly lower than those of the standard plan (all P<0.05), and the HI of simulation plan was lower than that of standard plan (P<0.05). The spinal cord Dmax of simulation plan was higher than that of standard plan (P<0.05), and there were no significant differences in the lung V20 and Dmean and heart V40 between standard plan and simulation plan (all P>0.05). Conclusions: CBCT-guided radiotherapy set-up errors have little effects on patients with upper and middle esophageal cancer. It improves the PTV irradiation dose and the treatment accuracy, and has a protective effect on spinal cord. Set-up errors have no significant effects on the dose distribution of the heart and lung. [ABSTRACT FROM AUTHOR]

Objective: To explore the effects of cone beam CT (CBCT)-guided radiotherapy set-up errors on irradiation dose of patients with upper and middle esophageal cancer. Methods: A total of 60 patients with middle and upper esophageal cancer admitted to our hospital from May 2017 to May 2019 were selected as the research subjects. All patients underwent CBCT images and planned CT image acquisition. CBCT scan was performed on patients before radiotherapy, and the CBCT image was matched with the planned CT image to obtain linear errors in three directions of left-right (x-axis), head-to-foot (y-axis) and front-to-back (z-axis), and the errors and distribution of errors were analyzed. The simulated actual irradiation system was used to carry out a simulation plan to obtain the actual irradiation target area and the irradiation dose of normal tissues, and compared it with the pre-treatment plan, and the effects of set-up errors on irradiation dose of patients were studied. Results: The overall set-up error of patients was(2.91±2.20) mm in x-axis, (3.89±2.17) mm in y-axis and (2.44±1.64) mm in z-axis, and the MPTV of x-axis was 4.054 mm, and MPTV of y-axis was 8.183 mm and MPTV of z-axis was 3.482 mm. The Dmin, Dmean and D95% of CI and PTV of the simulation plan were significantly lower than those of the standard plan (all P<0.05), and the HI of simulation plan was lower than that of standard plan (P<0.05). The spinal cord Dmax of simulation plan was higher than that of standard plan(P<0.05), and there were no significant differences in the lung V20 and Dmean and heart V40 between standard plan and simulation plan(all P>0.05). Conclusion: CBCT-guided radiotherapy set-up errors have little effects on patients with upper and middle esophageal cancer. It improves the PTV irradiation dose and the treatment accuracy, and has a protective effect on spinal cord. Set-up errors have no significant effects on the dose distribution of the heart and lung. [ABSTRACT FROM AUTHOR]

Hyaluronan (hyaluronic acid, HA) is a linear polysaccharide with disaccharide repeats of D-glucuronic acid and N-acetyl-D-glucosamine. As one of the most important glycosaminoglycans, HA is widely distributed in the human body including the extracellular matrix of the vitreous of the eye and cartilage tissue. The physiological functions of HA in the human body to maintain moisture, regulate osmotic pressure, lubricate joints and absorb shock are closely related to their physicochemical properties and rheological properties. The applications of HA-based functional materials mainly include the following three aspects: (1) Various HA-based derivatives and hydrogels are prepared based on the chemical modifications of hydroxyl, carboxyl, and acetamido groups. (2) HA and its derivatives have been widely used as drug carriers for targeted drug delivery based on HA interacting with receptors on the surface of cancer cells (such as CD44, RHAMM and LYVE-1 receptors). (3) HA hydrogels have been widely used in tissue engineering based on the close relationship between HA and human physiological activities. The HA-based biomaterials and their applications in the biomedical field (such as cancer targeted therapy, wound healing, postoperative adhesion, cartilage regeneration and osteoarthritis treatment) have been summarized in this review. [ABSTRACT FROM AUTHOR]

[Objective) As a special form of space utilization far vehicle base, sunken metro vehicle base faces greater risk in flood control and drainage. However, currently there are no available specifications and standards in this regard in China. Therefore, it is necessary to conduct in-depth research on the flood control and drainage design capacity of sunken vehicle base, clarify the relevant content in specification and standards to provide design reference for such projects. Method Relying on the Qianyin Parking Lot project of Ningbo Metris Line 5, the design requirements in existing specifications and stand ands for flood control and drainage are analyzed, as well as the flood prevention and control scheme of the sunken vehicle base. The flood control and drainage design schemes for different areas in sunken foundation pit are compared and analyzed according to 50-year and 100-year rainstorm return periods [Result & Conclusion] The sunken vehicle base should adopt reliable measures for waterlogging prevention and drainage to meet the basic requirements in this regard. In terms of flood control, the flood wall top elevation of sunken vehicle base and the pavement elevation at entry/exit should be higher than the 100-year flood level plus the safety height, and the height difference between the flood wall and the surrounding grand should be higher than the plot waterlogged level under 100-year rainstorm return period condition in terms of drainage, the principle of high water and high drainage should be adopted for the drainage of the cover roof cover over sunken foundation pit. The roof drainage capacity should be designed according to 100-year rainstorm return period, and the water should be directly discharged out of the foundations pit through gravity flow. The open area in the pit adopts pumping and drainage method, and the total drainage capacity of the rainwater pump station is designed according to 100-year rainstorm return period [ABSTRACT FROM AUTHOR]

Rice shrimp co-cultivation, as a circular agriculture model that integrates ecological, economic, and social benefits, has been widely applied in China. Accurately obtaining information on the planting area, spatial distribution, and changes of rice shrimp co-cultivation is of great significance for ensuring safe production, social supply of rice and shrimp, and formulating corresponding management and planning policies by government departments. Most of the existing methods for extracting rice shrimp farming fields used medium-resolution temporal images as data sources to analyze the characteristics of water or vegetation changes within a year to construct models. The accuracy of the extraction depended on the results of water or vegetation analysis, the boundaries were unclear and there was a lot of noise. To solve the problems of complex temporal analysis, low accuracy of extraction results, and incomplete boundaries in existing extraction methods, this paper used high-resolution images of a single temporal phase as the data source, without analyzing the temporal features of rice shrimp farming fields. Only the spatial features of rice shrimp farming fields on high-resolution images were used for high-precision extraction. We proposed a deep learning semantic segmentation model named EASNet (edge assisted segmentation network), which was mainly composed of three modules: feature extraction module (FE Module), edge assist module (EA Module), and information fusion Module (IF Module). The FE Module was used to extract multi-level and fused contextual semantic information features of the target object. The EA module used the unique edge "shrimp groove" of rice and shrimp farming fields as an auxiliary information for separate segmentation in the designed EA Module. The IF Module integrated the outputs of the FE Module and the EA Module, enabling the main task to not only enhanced the boundary structure information of rice shrimp farming fields but also learned the unique spatial and semantic information of rice shrimp farming fields. The experimental results showed that with the enhancement of the EA Module, the segmentation results of rice shrimp farming fields were more complete and the boundaries were clearer. The IoU (Intersection over Union) of semantic accuracy and the F1-Score of boundary accuracy were improved by 1.5% and 5.8%, respectively. The recall, IoU, and F1-Score of overall semantic accuracy reached 0.970, 0.964, and 0.930, respectively. The Recall and F1-Score of boundary accuracy reached 0.864 and 0.859, while the Recall and F1-Score of relaxed boundary accuracy reached 0.876 and 0.913. The trained EASNet model was applied to the whole area of Xuyi County, and the spatial distribution map of rice shrimp farming fields in Xuyi County in 2020 was obtained. In comparison with the results of rice shrimp breeding fields extracted by the traditional Water Seasonal Difference method and the Random Forest method, our method obtained the optimal results with an OA(overall accuracy) of 96.71% and a Kappa coefficient of 0.934. The method used in this paper has higher accuracy, lower missing rate, more regular boundaries, and fewer instances of similar integration in extracting results. It can provide a basis for natural resource surveys, and government departments to formulate corresponding rice shrimp breeding management and planning policies. [ABSTRACT FROM AUTHOR]

The oil content of oily sludge was determined by infrared spectrophotometry, ultraviolet spectrophotometry and azeotropic distillation. The results showed that the azeotropic distillation method was suitable for most oily sludge with oil content, and the detection limit was the lowest 0.57～2.28 mg/L. The UV spectrophotometry can only detect petroleum monsters with characteristic absorption at wavelengths of 226.0 nm and 257.5 nm, with the lowest relative deviation of 1.47% at 226.0 nm and 1.60% at 257.5 nm, respectively. Infrared spectrophotometry is often used to detect soil water and petroleum in soil, and can only measure characteristic absorption peaks at wave numbers of 2 930,2 960 cm-1 and 3 030 cm-1.. [ABSTRACT FROM AUTHOR]

Objective · To explore the relationship among perceived stress, personality traits and panic disorder (PD) symptoms, and to test the mediating effect of perceived stress on PD symptoms in different personality traits. Methods · A total of 55 PD patients were selected according to Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (DSM-5). The NEO Five-Factor Inventory (NEO-FFI) was used to measure the personality traits. The Panic Disorder Severity Scale (PDSS) was used to measure the PD symptoms severity. The Perceived Stress Scale (PSS) was used to measure the level of the perceived stress. Results · Both the neuroticism, agreeableness subscale scores of NEO-FFI and scores of PSS were significantly correlated with the total scores of PDSS, and the correlation coefficient were r0.379 (P0.004), r-0.420 (P0.001) and r0.330 (P0.014), respectively. The mediating effect analysis showed that perceived stress completely mediated the effect of agreeableness on PD symptoms, and the mediating effect was 32.43%. Conclusion · In personality traits, neuroticism may be positively correlated with PD symptoms, while agreeableness may be negatively correlated with PD symptoms. The perceived stress may play a completely mediating role between agreeableness and PD symptoms. [ABSTRACT FROM AUTHOR]

A mobile robot based on a normal grid map could not obtain the comprehensive environmental information in a greenhouse because of the less number and limited location of carried sensors. An incorrect planning path may arise. The system adopted a way to build a composite grid map based on the comprehensive environmental information in greenhouse. Firstly, wireless sensor network regularly collected data of temperature and humidity and sent them to the robot. These data had heavy impacts on mobile robot’s passing through in greenhouse. Secondly, when the rate of change of temperature or humidity data reached the threshold, the system used the method of threshold segmentation and interpolation to establish the grid maps for temperature and humidity respectively. Finally, the system combined the grid map for temperature, the grid map for humidity and the grid map for interior material barrier in a greenhouse to build a dynamically updated composite grid map. After testing, when the system adopted the A*algorithm, the rate of success to avoid area of high temperature and high humidity based on the composite grid map at threshold of ± 10% was 2. 5 times to normal grid map. The time of completion was 1. 05 times to normal grid map. The results show that the composite grid map can improve the success rate of the path planning and the robot does not meet the problem of slow response of the robot due to the dynamic updating of the composite grid map. The real-time performance satisfies the actual requirements of the system. [ABSTRACT FROM AUTHOR]

Aiming al the potentiality of user interest as well as it’s instability and time-mobility on high real-time business in recommender systems, this paper presented a recommendation method based on user potential temporal preference. Through analysis of the relationship between history of user behavior and user potential interest deeply, it proposed a user interest mining model based on probabilistic topic model, to avoid the ignorance of user potential interest in traditional way. At the same time, based on considerations of time-sensitive in high real-time business, it combined with hidden Markov model to capture the user preference in real time and found the drift of interests sequence. At last, related experiments verifiy the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]