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Beef cattle in the farm are active, which leads the collection of posture of the beef cattle changeable, so it is difficult to automatically measure the body size of the beef cattle. Aiming at the above problems, an automatic measurement method for beef cattle's body size under multi-pose was proposed by analyzing the skeleton features of beef cattle head and the edge contour features of beef cattle images. Firstly, the consumer-grade depth camera Azure Kinect DK was used to collect the top-view depth video data directly above the beef cattle and the video data were divided into frames to obtain the original depth image. Secondly, the original depth image was processed by shadow interpolation, normalization, image segmentation and connected domain to remove the complex background and obtain the target image containing only beef cattle. Thirdly, the Zhang-Suen algorithm was used to extract the beef cattle skeleton of the target image, and calculated the intersection points and endpoints of the skeleton, so as to analyze the characteristics of the beef cattle head to determine the head removal point , and to remove the beef cattle head information from the image. Finally, the curvature curve of the beef cattle profile was obtained by the improved U-chord curvature method. The body measurement points were determined according to the curvature value and converted into three-dimensional spaces to calculate the body size parameters. In this paper, the postures of beef cattle, which were analyzed by a large amount of depth image data, were divided into left crooked, right crooked, correct posture, head down and head up, respectively. The test results showed that the head removal method proposed based on the skeleton in multiple postures hads head removel success rate higher than 92% in the five postures. Using the body measurement point extraction method based on the improved U-chord curvature proposed, the average absolute error of body length measurement was 2.73 cm, the average absolute error of body height measurement was 2.07 cm, and the average absolute error of belly width measurement was 1.47 cm. The method provides a better way to achieve the automatic measurement of beef cattle body size in multiple poses.

With the continuous increase of train speed, the strip wear increases, which poses a threat to the safety and economy of pantograph-catenary system. At present, the railway department still uses the traditional manual climbing method to inspect the strip wear, which is inefficient, unsafe and interferes with normal traffic. Therefore, it is urgent to explore a simple and efficient method for predicting the strip wear amount to guide the maintenance and replacement of the strip. By changing the current and temperature parameters, the strip wear amount decreases with the increase of temperature under lowcurrent condition; while, the strip wear amount first decreases and then increases with the increase of temperature under high-current condition. A wear prediction model of the metal-impregnated carbon strip considering the temperature effect is established based on the PLSR and the relative error of the model detection is less than 6%. It is concluded that the sensitivity of wear amount to the change of influencing factors is significantly different for strips of different materials. The results are of great significance to improve the wear prediction model of strip, reduce the cost of railway operation and maintenance, and improve the stability of the pantograph-catenary system. [ABSTRACT FROM AUTHOR]

Mistuning changes the vibration of bladed disks dramatically. Various aeroelastic models have been used to investigate the free vibration and forced response problems of mistuned bladed disks. Most of these models used simplified structural and/or aerodynamic models. The traditional way to incorporate the aerodynamic coupling in the high-fidelity structural models is to use the cantilever-blade normal modes to calculate the unsteady aerodynamic forces. In this paper, a new reduced-order modeling approach is developed by using the tuned system modes to calculate the unsteady aerodynamic forces directly. This new approach is applied to an industrial rotor. The results show that aerodynamic coupling has significant effects on the vibration of bladed disks for the case studied. Also, constraint modes are needed to yield accurate results if cantilever-blade normal modes are used to calculate the unsteady aerodynamic forces. However, using the tuned system modes to calculate the unsteady aerodynamic forces saves a significant amount of computation time compared to the method using both cantilever-blade normal modes and constraint modes.

BACKGROUND: Percutaneous kyphosis is improved on the basis of vertebroplasty, which can well restore the height of compressed vertebral body and reduce bone cement leakage. In recent years, it has been widely used in the treatment of osteoporotic vertebral compression fracture. However, it is often reported that there are recurrent fractures of the enhanced vertebral body and adjacent vertebral body after surgery, and the related factors affecting the recurrent fracture are still controversial. OBJECTIVE: To identify the risk factors for the fractures secondary to percutaneous kyphoplasty for treating osteoporotic vertebral compression fractures in the elderly by meta-analysis. METHODS: A comprehensive search was conducted for the studies published from January 2009 to April 2019 on the risk factors for secondary fractures after percutaneous kyphoplasty in the Cochrane Library, PubMed, CBM, CNKI and Wan Fang databases and manually as well. After the relevant data were extracted, statistical analysis was carried out with RevMan 5.3 software. RESULTS AND CONCLUSION: (1) The secondary fracture after percutaneous kyphoplasty for osteoporotic vertebral compression fracture was related to age [WMD=1.87, 95%CI (0.79, 2.95), P < 0.05], bone mineral density [WMD=-0.46, 95%CI (-0.61, -0.31 ), P < 0.05], bone cement leakage [OR=2.68, 95% Cl (2.11, 3.39), P < 0.000 01], correction of kyphosis angle after primary operation [WMD=2, 95% Cl (0.34, 3.88), P=0.02] and recovery rate of vertebral height after primary operation [WMD=5.25, 95% Cl (2.16, 8.34), P=0.000 9]. (2) The secondary fracture after percutaneous kyphoplasty for osteoporotic vertebral compression fracture was not related to sex [OR=0.83, 95% Cl (0.67, 1.02), P > 0.05], body mass index [WMD=-0.27, 95% Cl (-1.06, 0.51), P=0.49], cement volume [WMD=0.06, 95% Cl (-0.21, 0.32), P=0.68], surgical approach [OR=0.87, 95%CI (0.61, 1.25), P=0.46], primary fracture was thoracolumbar segment (T11-L.,) [OR=1.48, 95% Cl (0.93, 2.38), P=0.1]. (3) These results suggest that age, bone mineral density, bone cement leakage, correction of kyphosis angle after primary operation and recovery rate of vertebral height after primary operation may be the risk factors closely correlative to the secondary fracture after percutaneous kyphoplasty. There has not been enough evidence to support the associations between the secondary fracture and sex, body mass index, cement volume, surgical approach or thoracolumbar spine, and the above conclusions need to be studied and verified by more high quality literature in the future. [ABSTRACT FROM AUTHOR]

Abstract: The surface of Y3Al5O12:Ce3+ phosphor prepared by solid-state reaction was modified by hydrofluoric acid wet etching. The SEM pictures show that the edge-angles-rich surface of the phosphor particles becomes smooth and the XRD spectra show that the surface crystallinity is improved after modification for more than 3h. Consequently, the photoluminescence emission from phosphor particles with smooth surface presents a higher quantum yield (increased by 5.5%) than that without modification, and a lower backscattering light by the smoothed phosphor particles is also found, which suggests better surface characteristics of light absorption, transparency and crystallinity. [Copyright &y& Elsevier]

Different nitrogen sources, pure \N2, pure NO, and NO mixed with \O2 (25% NO + 75% \O2), are used to confirm the effects of \N^+, \N2^{+}, and \NO^+ ion implantation on the p-type conversion of ZnO:Al (AZO) films by plasma-immersion ion implantation (PIII) based on N–Al codoping mechanism. For the plasma of \N2, NO, and NO mixed with \O2, the major implanted ions are, respectively, \N2^{+} ions, \N2^{+} mixed with \NO^+ ions, as well as \N^+ mixed with \O^+ ions, confirmed by the optical emission spectra of plasma. After activation by postimplanted annealing, the photoluminescence and X-ray photoelectron spectroscopy analyses indicate that the implanted \N^+, \N2^{+}, and \NO^+ ions replace the O sites and form nitrogen atom substitutions at O sites [(\NO)], nitrogen molecule substitutions at O sites [(\N2)O], as well as zinc nitrite and zinc nitrate, respectively. Among all the N-induced defects, only NO contribute to the p-type conversion of ZnO films. That explains why p-type conversion is only successfully achieved by NO mixed with \O2, while others still remain n-type conductivity. The mechanism of p-type conversion by \N2, NO, and NO mixed \O2 PIII was investigated in this paper. [ABSTRACT FROM AUTHOR]

Some studies have investigated the role of cholesterol in the progression of colorectal cancer (CRC). However, the underlying mechanism of action is not clear. In this study, we used bioinformatics tools to elucidate the molecular mechanisms involved. We initially obtained CRC datasets from the Gene Expression Omnibus (GEO) database and hypercholesterolemia data from GeneCards and DisGeNE. Common differentially expressed genes (DEGs) were determined by using Venn diagram web tools. Next, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses using the Database for Annotation, Visualization, and Integrated Discovery (DAVID). The hub gene was identified through common expression pattern analysis and survival analysis. Finally, we conducted an immune regulatory point analysis and predicted target drugs based on the hub gene. The results of our analysis revealed 13 common DEGs, with endothelin receptor type A (EDNRA) identified as the hub gene linking hypercholesterolemia and CRC. The results of the GO analysis showed that the common DEGs were primarily associated with the G-protein coupled receptor signaling pathway, extracellular space, and receptor binding. The results of the KEGG pathway enrichment analysis indicated enrichment in pathways related to cancer and the phospholipase D signaling pathway. Additionally, we identified potential target drugs, including Podocarpus montanus, Diospyros kaki, Herba Salviae japoniae, sitaxentan, and ambrisentan. We found that EDNRA might be an underlying biomarker for both hypercholesterolemia and CRC. The predicted target drugs provide new strategies for treating CRC.