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Additive manufacturing technology brings new revolutionary potential for the development of carbon fiber reinforced polymer composites. Continuous carbon fiber reinforced composites developed using fused deposition modeling technology have the characteristics of high specific strength, high specific modulus, light weight, and flexible design, which is the solution direction for low-cost, rapid, and flexible application of advanced composite materials in the future. In this paper, the preparation of continuous carbon fiber reinforced polymer composites with continuous carbon fibers as reinforcement and thermoplastic/thermoset as matrix, surface modification and their mechanical properties are investigated, the interfacial characteristics and properties of continuous carbon fiber reinforced polymer composites under different pretreatment processes, auxiliary processes and post-treatment processes are studied, and the connection between the micro-morphology and the mechanical properties of this composite is further analyzed. The direction of defect resolution of continuous carbon fiber reinforced polymer composites fabricated by fused deposition technology is provided, and the future development direction is envisioned. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of curcumin on the growth performance, slaughter performance, apparent nutrient digestibility, intestinal morphology, and digestive enzyme activity of meat rabbits. One hundred and sixty healthy weaned meat rabbits were randomly divided into four groups (forty replicates per group and one rabbit per replicate). The control group was fed a basal diet and the test groups (T1, T2 and T3) were fed diets supplemented with 50, 100 and 150 g/t curcumin in the basal diet, respectively. The study lasted for 28 days, including a pre-feeding period of 7 days and a formal trial period of 21 days. The results showed that diets supplemented with curcumin significantly increased rabbits' body weight gain and average daily feed intake; Apparent digestibility of energy, crude protein, crude fat, crude fibre, NDF and ADF; Jejunal villus height, the ratio of villus height to crypt depth; The activities of amylase and lipase in jejunal and caecal digesta and cellulase in caecal digesta; Caecal mucosal thickness, eviscerated dressing percentage, and dorsal and abdominal hair thickness (p <.05). Diets supplemented with curcumin significantly decreased rabbits' feed to gain ratio, jejunal crypt depth and thickness of the intestinal wall (p <.05). In conclusion, curcumin is a kind of valuable feed additive, which can improve the nutrient digestibility, growth performance, slaughter ratio and fur development of meat rabbits by improving digestive tract development and digestive enzyme activity. The appropriate dosage in the meat rabbit diet is 100 g/t. Dietary supplementation of curcumin improved the growth performance, gastrointestinal digestive enzyme activities and slaughter performance of meat rabbits. Dietary supplementation of curcumin increased the antioxidant capacity of meat rabbits. Curcumin could be used as a new kind of feed additive for meat rabbits. [ABSTRACT FROM AUTHOR]

As the oil and gas industry is crucial to the global energy market, policymakers need accurate information about local oil reserves and the harmful environmental effects of drilling, such as damage to public land and wildlife. Therefore, accurate automatic detection of the location, distribution and quantity of oil wells is essential. Recent advancements in remote sensing and deep learning technologies provide potential solutions for automatic oil wells detection using high-resolution remote sensing images. This study proposes an optimized Faster R-CNN-based model that incorporates three key modifications to improve the accuracy of oil wells detection. The modifications include replacing the VGG16 network with the ResNet50 network to improve the model's feature extraction capabilities, substituting the ordinary convolution of ResNet with a dilated convolution to improve the model's receptive field, and constructing a feature pyramid to improve the model's ability to detect small targets and objects at different scales. Also, an edge detection module is added to further improve the detection accuracy. Furthermore, a new framework based on Faster R-CNN and leveraging Soft-NMS (Non-Maximum Suppression) and the proposed ClusterRPN sub-network is combined to address the problem of clustered oil wells detection. Experimental results demonstrate that the proposed optimized model outperforms existing models. [ABSTRACT FROM AUTHOR]

Three new compounds, namely massonside C (1), massonianoside F (2), and 3, 8-dimethyl- herbacetin-7-O-β-D-glucopyranoside (3), together with five known compounds (4–8), were isolated from the fresh needles of Pinus massoniana. Their structures were established by 1D, 2D NMR, HRMS and comparison with the literature data. The absolute configuration of 1 was confirmed by a combination of X-ray single crystal analysis. All isolated compounds were evaluated for the protective effect of human umbilical vein endothelial cells against oxidative damage. [ABSTRACT FROM AUTHOR]

A random poly(L-alanine-co-L-lactic acid) (PAL) with excellent thermo-sensitivity and no cytotoxicity was synthesized by the structure-controlled polycondensation from naturalL-alanine andL-lactic acid. Only those PALs in which the contents ofL-alanine structural unit are rigidly controlled in the smaller range of 53–65% show a reversible lower critical solution temperature of 35–60°C. The change of secondary structure in poly(L-alanine) segments by the introduction ofL-lactic acid structural unit plays a decisive role in regulating the thermo-sensitivity of PAL. The viability of HeLa cells exposed to PAL reaches up to 91–116% after incubation of 24 and 72 h, indicating no cytotoxicity. Furthermore, PAL can easily form curcumin-loaded nano-carriers through its thermo-sensitivity and self-assembly. The curcumin-loaded PAL nano-particles are observed to clearly internalize into the cells by confocal laser-scanning microscopy, and thus can be used as a potential nano-drug-carrier. [ABSTRACT FROM AUTHOR]

Two new sesquiterpene glycosides, namely massonside A (1) and massonside B (2), were isolated from the n-Bu extract of the fresh needles of Pinus massoniana Lamb. Their structures were established by 1D, 2D nuclear magnetic resonance and high-resolution mass spectrometry. Their biological activities were profiled by the anti-HBV and anti-HCV assays. [ABSTRACT FROM AUTHOR]

A kind of blue phase liquid crystal (BPLC), consisting of nematic liquid crystal, E7, and chiral dopants, CB15 and R1011, was investigated by doping PbS nanoparticles. The blue phase temperature range was extended from 3oC to 4.6°C by doping PbS nanoparticles with diameters around 9.6 nm. A kind of porous texture was observed both in the forming process of PbS nanoparticles doped BPLCs as well as in the BPLCs (with/without PbS nanoparticles) under assisting electric field. The porous texture may indicate that the liquid crystals molecule should be reoriented during the formation process of PbS nanoparticles doped BPLCs. [ABSTRACT FROM AUTHOR]

Context: There are few reports of endothelial progenitor cells (EPCs) in peripheral blood have been found in patients with gastric cancer. Objective: We quantified EPCs in the peripheral blood of patients with gastric cancer, with the expectation that this approach might lead to a new marker for the diagnosis of gastric cancer. Methods: We enumerated CD34+/CD133+ EPCs in the peripheral blood of 145 subjects by use of flow cytometry. Results and conclusion: The quantity of peripheral blood EPCs in patients with gastric cancer are correlated with patient's age. In addition, the number of peripheral blood EPCs in patients with gastric cancer increased with tumor node metastasis stage and histological differentiation of the cancers, and with the operative status of the patients. [ABSTRACT FROM AUTHOR]