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Planning of laser scanning path is the key process strategy of selective laser melting (SLM) additive manufacturing technology. Combining the significant structural characteristics of a three-dimensional model to realize process path planning is an important measure to improve the forming quality of parts. An SLM regional path planning method based on suspension recognition was proposed. By identifying the suspension characteristic region of the three-dimensional model, combined with the contour offset algorithm, the forming region segmentation and scanning path planning are realized. The effects of scanning line angle, interlayer rotation and different offset distance on the forming quality of suspension structure characteristics were studied by means of numerical simulation and process test. The results show that when the overhanging edge is offset by a reasonable distances and the scanning strategy parallel to the overhanging edge is adopted in this area, the deformation and residual stress on the overhanging edge can be reduced by 54% and 73% at most.

Cervical cancer is a typical cancer characterized by abnormal cell growth in the cervical area. Ginkgo biloba L. is a deciduous tree of the genus Ginkgo, possessing anti-cancer effects. The aim of this study was to explore the effect of strain J1 from Ginkgo biloba L. on apoptosis of cervical cancer cells. Bacteriostatic activity test, MTT assay and Flow cytometry were used in this study. Crude extract of J1 fermentation reduced cell growth in cervical cancer. The crude extract of the fermentation broth of strain J1 had a good inhibitory effect on Staphylococcus aureus. The crude extract of the J1 fermentation had no toxic effect on normal WISH cells in the range of anti-cervical cancer concentration. Crude extract of J1 fermentation induced apoptosis and regulated cell cycle in cervical cancer. The active compounds were separated and identified by preparative chromatography, and more than ten compounds were obtained. Our study suggests that the crude extract of J1 fermentation from Endophytic fungi of Ginkgo biloba reduced cell growth, and promoted apoptosis of cervical cancer, and is a potential therapeutic strategy for the treatment of cervical carcinoma.

Polyvalent passive vaccines can act fast in resisting various bacteria with good efficacy, and they have application value in aquaculture. This study prepared live and inactivated Vibrio fluvialis mouse antisera (L-VF-antiserum and I-VF-antiserum), and administered them to goldfish (Carassius auratus) infected with V. fluvialis and Aeromonas hydrophila. The passive protective rates of live and inactivated mouse antisera against V. fluvialis were 60% (p < 0.05) and 40% (p < 0.05), and their passive cross-protective rates against A. hydrophila were 42.86% (p < 0.05) and 35.71% (p < 0.05), respectively. Furthermore, the two mouse antisera could recognize the bacteria in vitro; the content of bacteria in the C. auratus kidney decreased (p < 0.05), the phagocytic activity of C. auratus leukocytes was enhanced (p < 0.05), and the expression of inflammatory genes and activity of antioxidant factors decreased (p < 0.05). Moreover, the kidney, spleen, and intestinal tissue structures were intact, and the apoptosis and DNA damage were decreased (p < 0.05) among the kidney cells. The live V. fluvialis antiserum contained more antibodies against the outer membrane proteins of V. fluvialis than the inactivated mouse antiserum. The immunoprotective abilities of the live V. fluvialis antiserum were higher than those of the inactivated antiserum, and the antiserum of live V. fluvialis immunity demonstrated potential application value as a polyvalent passive immune vaccine in fish. [ABSTRACT FROM AUTHOR]

The detection of keyhole-induced pore positions is a critical procedure for assessing laser welding quality. Considering the detection error due to pore migration and noise interference, this research proposes a regional prediction model based on the time–frequency-domain features of the laser plume. The original plume signal was separated into several signal segments to construct the morphological sequences. To suppress the mode mixing caused by environmental noise, variational modal decomposition (VMD) was utilized to process the signals. The time–frequency features extracted from the decomposed signals were acquired as the input of a backpropagation (BP) neural network to predict the pore locations. To reduce the prediction error caused by pore migration, the effect of the length of the signal segments on the prediction accuracy was investigated. The results show that the optimal signal segment length was 0.4 mm, with an accuracy of 97.77%. The 0.2 mm signal segments failed to eliminate the negative effects of pore migration. The signal segments over 0.4 mm resulted in prediction errors of small and dense pores. This work provides more guidance for optimizing the feature extraction of welding signals to improve the accuracy of welding defect identification. [ABSTRACT FROM AUTHOR]

Submarine landslides always occur along gently inclined continental slopes, but the reasons for such failure of low-angle submarine slopes are unclear and contentious. A short discussion is presented here to some recent published papers including some inspirations about the low-angle failure of submarine slopes. Because fluid overpressure could lead to steepening slopes before landslide, the inclination of the slopes at failure may be underestimated. We offer a new perspective on low-angle failure of low-permeability slopes.

Pseudorabies virus (PRV) is considered to be a promising oncolytic virus that has potential as a cancer gene therapy drug. In this study, PRV-DCD-1-70 was used as a vector to carry exogenous genes IL-18, IFN-γ and PH20 to construct novel recombinant PRV, rPRV-PH20 and rPRV-IL-18-γ-PH20, and their tumorolytic effects were evaluated in vitro and in vivo. Our study showed that recombinant PRV lysed all four tumor cell lines, Pan02, EMT-6, CT26 and H446, and rPRV-IL-18-γ-PH20 showed the best tumor lysis effect. Further studies in mice bearing Pan02 tumors showed that recombinant PRV, especially rPRV-IL-18-γ-PH20, were able to inhibit tumor growth. Moreover, an immunohistochemical analysis indicated that the recombinant PRV effectively increased the infiltration of CD4+T and CD8+T cells and enhanced the anti-tumor immune response of the organism in vivo. Overall, PRV carrying PH20 and IL-18-γ exogenous genes demonstrated anti-tumor effects, providing a foundation for the further development and application of PRV as a novel tumor oncolytic virus vector. [ABSTRACT FROM AUTHOR]