Synergistic Enhancement of the Strength-Ductility for Stir Casting SiCp/2024Al Composites by Two-Step Deformation

Fu‑xiang Cao,Kun‑kun Deng,Cui‑ju Wang,Kai‑bo Nie,Wei Liang,Jian‑feng Fan 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

The 10 μm 10 vol% SiCp/2024Al composites sheet was successfully fabricated by semi-solid stir casting followed withtwo-step deformation (extrusion and rolling). The two-step thermal deformation solves the sheet rolling formability of theSiCp/2024Al composites produced by stir casting. Compared with the SiCp/2024Al composites prepared by traditional powdermetallurgy, this paper innovatively studied the synergistic enhancement between CuAl2phase and SiCpon the mechanicalproperties. The result shows that the two-step deformation can significantly improve the uniformity of the distribution of SiCpand CuAl2phases. At the same time, the average size of the SiCpand CuAl2phase decreases after the two-step deformation. During the hot extrusion, SiCphas an obvious hindrance to the refinement of the CuAl2phase. Moreover, the SiCp/2024Alcomposites sheet exhibits excellent yield strength (295 MPa), ultimate tensile strength (489 MPa), and elongation (10.42%). The performance improvement of SiCp/2024Al after two-step thermal deformation is mainly attributed to the improvedinterface bonding strength of SiCp-2024 Al matrix, the refined SiCpand the more uniform distribution of SiCp.

EFFECTS OF CARBON NANOTUBES ON RAT LIVER AND BRAIN

FU-DE WANG,CHAN JIN,LING-LING CAO,HAO LIANG,CHUN-WANG MA 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.7

Carbon nanotubes (CNTs) have been widely applied in various ¯elds due to excellent physicaland chemical properties. As production and applications of nanotubes expand, public concernabout their potential risks to human health has also risen. In the present study, the e®ects ofCNTs on rat liver and brain by single intratracheal instillation were detected. CNTs [eithersingle-walled carbon nanotubes (SWCNTs) or multi-walled carbon nanotubes (MWCNTs)] couldbe seen in the lung and liver indicating the transfer of CNTs by blood stream. CNTs could induceoxidative stress in liver with elevated Malondialdehyde (MDA) level and degressive GSH level,superoxide dismutase (SOD) and CAT activity. To brain, maybe due to the blood brain barrierand the increased SOD and CAT activity, serious oxidative stress of brain did not occur.

Two new triterpenoid saponins derived from the leaves of Panax ginseng and their antiinflammatory activity

Li, Fu,Cao, Yufeng,Luo, Yanyan,Liu, Tingwu,Yan, Guilong,Chen, Liang,Ji, Lilian,Wang, Lun,Chen, Bin,Yaseen, Aftab,Khan, Ashfaq A.,Zhang, Guolin,Jiang, Yunyao,Liu, Jianxun,Wang, Gongcheng,Wang, Ming-Kui The Korean Society of Ginseng 2019 Journal of Ginseng Research Vol.43 No.4

Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside $LS_1$ (1) and 5,6-didehydroginsenoside $Rg_3$ (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with $IC_{50}$ of $37.38{\mu}M$ compared with that of NG-monomethyl-L-arginine ($IC_{50}=90.76{\mu}M$). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin $E_2$ and tumor necrosis factor-${\alpha}$. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.

Effects of Glucagon-Like Peptide-2-Expressing Saccharomyces cerevisiae Not Different from Empty Vector

( Xi Zhong ),( Guopeng Liang ),( Lili Cao ),( Qi Qiao ),( Zhi Hu ),( Min Fu ),( Hong Bo ),( Qin Wu ),( Guanlin Liang ),( Zhongwei Zhang ),( Lin Zhou ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.10

Saccharomyces cerevisiae (S. cerevisiae) and glucagon-like peptide-2 (GLP-2) have been employed to improve the intestinal development of weaned animals. The goal of this study was to determine whether either exogenous S. cerevisiae or GLP-2 elicits major effects on fecal microbiotas and cytokine responses in weaned piglets. Ninety-six piglets weaned at 26 days were assigned to one of four groups: 1) Basal diet (Control), 2) empty vector-harboring S. cerevisiae (EV-SC), 3) GLP-2-expressing S. cerevisiae (GLP2-SC), and 4) recombinant human GLP-2 (rh-GLP2). At the start of the post-weaning period (day 0), and at day 28, fecal samples were collected to assess the bacterial communities via sequencing the V1-V2 region of the 16SrRNA gene, and piglets’ blood was also sampled to measure cytokine responses (i.e., IL-1β, TNF-α, and IFN-γ). This study revealed that, on the one hand, although S. cerevisiae supplementation did not significantly alter the growth of weaned piglets, it induced increases in the relative abundances of two core genera (Ruminococcaceae_norank and Erysipelotrichaceae_norank) and decreases in the relative abundances of two other core genera (Lachnospiraceae_norank and Clostridiale_norank) and cytokine levels (IL-1β and TNF-α) (p < 0.05, Control vs EV-SC; p < 0.05, rh-GLP2 vs GLP2-SC). On the other hand, GLP-2 supplementation had no significant influence on fecal bacterial communities and cytokine levels, but it produced better body weight and average daily gain (p < 0.05, Control vs EV-SC; p < 0.05, rh-GLP2 vs GLP2-SC). Therefore, altered fecal microbiotas and cytokine response effects in weaned piglets were due to S. cerevisiae rather than GLP-2.

A high-resolution timescale for the Miocene Shanwang diatomaceous shale lagerstätte (China): development of Wavelet Scale Series Analysis for cyclostratigraphy

Jifeng Yu,Xinlong Pang,Wenzhao Fu,Jason Hilton,Mingmei Liang,Zongkai Jiang,Xiuli Zhao,Wenyan Qiao,Suo Shi,Diandong Zhang,Huitao Cao,Haibo Jia,Yadong Wang,Xiaoke Hu,Rui Zhang 한국지질과학협의회 2021 Geosciences Journal Vol.25 No.5

The Miocene aged Shanwang Formation from the Shanwang National Geopark in China represents a succession of lacustrine diatomaceous shales containing an abundant and diverse biota with lagerstätte fossilization of soft tissues. To date, the Shanwang Formation has not been investigated for cyclostratigraphy nor has it been dated with high precision methods. Now we use thorium data as a paleoenvironmental and paleoclimatic proxy to conduct a detailed cyclostratigraphic analysis. A new and simple cyclostratigraphic method, Wavelet Scale Series Analysis (WSSA) is developed to recognize Milankovitch cycles. A total of three short eccentricity and fifteen precession cycles are identified; obliquity cycles are not apparent. In the sedimentary succession, the corresponding precession and short eccentricity cycles are 1.17 m and 4.98 m thick respectively, with this verified by Correlation Coefficient (COCO) analysis and Multitaper-Method (MTM) spectral analysis. We estimate the studied interval was deposited over a duration of 0.3 Myr with a depositional rate of c. 5.7 cm/kyr. Paleomagnetic and radio isotope dating data shows that the diatomaceous shale was deposited during Chron C5En, which places it at approximately 18.5 Ma during the Burdigalian stage of the Early Miocene, rather than in the Middle Miocene as previously thought. The Shanwang lagerstätte biota therefore predates the Middle Miocene Climate Optimum (MMCO) and did not form within it. The geological time scale with a high resolution of 20 kyr was set accordingly.

Influence of Layer Thickness Ratio on the Mechanical and Failure Properties of Soft-Hard Interbedded Rock-like Material

Qiang Xie,Hao Gao,Yuxin Ban,Xiang Fu,Xiaowen Liang,Zhilin Cao,Jun Duan 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.11

To figure out the influence of soft-hard layer thickness ratio on specimens’ mechanical properties evolution and microcracking mechanism, combined with digital image correlation technology and acoustic emission facility, uniaxial compression tests were conducted on soft-hard interbedded rock-like materials considering seven bedding dip angles and two soft-hard layer thickness ratios. The results are as follows: 1) The failure mode and failure pattern of layered rock masses are mainly determined by the bedding dip angle α and are less related to the soft-hard thickness ratio. With the increase of dip angle, the failure strength curve of the specimen is approximately U-shaped, and the soft-hard layer thickness ratio affects the U-shaped. The decrease in soft-hard layer thickness ratio will reduce the uniaxial compressive strength of specimens with low dip angles (α≦30°), cause differences in the evolution path of local strain fields of layered rock masses and reduce the horizontal displacement of the main crack. 2) The increase of the proportion of soft layer in the soft-hard layer thickness ratio will reduce the proportion of tensile cracks in the tensile failure specimens and shear cracks in the shear failure specimens, complicating the process of cracks of the layer rock mass. 3) Increasing the proportion of soft layers in the soft-hard layers thickness ratio promotes the generation of secondary cracks in layered rock masses and further reduces the integrity of specimens. Finally, through the findings in this paper, it can provide a reference for analyzing the crack propagation behavior of layered rock.

Enrichment of linoleic acid from yellow horn seed oil through low temperature crystallization followed by urea complexation method and hypoglycemic activities

Kang Yang,Ying Tang,Huayu Xue,Xiaoyue Ji,Fu-Liang Cao,Shouke Li,Li Xu 한국식품과학회 2024 Food Science and Biotechnology Vol.33 No.1

Yellow horn (Xanthoceras sorbifolia Bunge) contained abundant linoleic acid (LA), accounting for about 44% of its lipid. Here, LA was enriched by low temperature crystallization followed by urea complexation, and the optimal enrichment conditions were optimized with response surface methods (3:1 ratio of EtOH/FFA, crystallization at − 25 °C for 24.5 h; 2:1 ratio of urea/FFA1, 6.6:1 ratio of EtOH/urea, crystallization at − 10 °C for 22.4 h). Under these conditions, the final LA content and recovery were 97.10% and 62.09%, respectively. In vitro hypoglycemic studies suggested that the LA extract with stronger inhibition on α-glucosidase and lower one on α-amylase than acarbose exhibited a positive control for carbohydrate digestion with lower adverse effects. The enzyme kinetics and Lineweaver–Burk plots analyses revealed a reversible competitive inhibition on α-amylase and α-glucosidase. The findings of this research provided insights for the development of the LA extract as the functional component of health food.

Effects of stocking density on the homeostasis of uric acid and related liver and kidney functions in ducks

Lin Peiyi,Liufu Sui,Wang Jinhui,Hou Zhangpeng,Liang Yu,Wang Haiyue,Li Bingxin,Cao Nan,Liu Wenjun,Huang Yunmao,Tian Yunbo,Xu Danning,Li Xiujin,Fu Xinliang 아세아·태평양축산학회 2024 Animal Bioscience Vol.37 No.5

Objective: Stocking density (SD) is an important issue in the poultry industry, which is related to the production performance, intestinal health and immune status. In the present study, the effects of SD on the metabolism and homeostasis of uric acid as well as the related functions of the liver and kidney in ducks were examined. Methods: A total of 360 healthy 56-day-old Shan-ma ducks were randomly divided into the low stocking density (n = 60, density = 5 birds/m2 ), medium stocking density (n = 120, density = 10 birds/m2 ) and high stocking density groups (HSD; n = 180, density = 15 birds/m2 ). Samples were collected in the 3rd, 6th, and 9th weeks of the experiment for analysis. Results: The serum levels of uric acid, lipopolysaccharide and inflammatory cytokines (interleukin-1β [IL-1β], IL-8, and tumor necrosis factor-α [TNF-α]) were increased significantly in the HSD group. Serious histopathological lesions could be seen in both the livers and kidneys in the HSD group in the 9th week. The mRNA expression levels of inflammatory cytokines (IL-8 and TNF-α) and related pathway components (toll-like receptor 4, myeloid differentiation primary response gene 88, and nuclear factor-κB) were increased significantly in both the livers and kidneys in the HSD group. The mRNA expression levels of enzymes (adenosine deaminase, xanthine oxidase, phosphoribosyl pyrophosphate amidotransferase, and phosphoribosyl pyrophosphate synthetase 1) related to the synthesis of uric acid increased significantly in the livers in the HSD group. However, the mRNA expression level of solute carrier family 2 member 9, which plays an important role in the excretion of uric acid by the kidney, was decreased significantly in the kidneys in the HSD group. Conclusion: These results indicated that a higher SD could cause tissue inflammatory lesions in the liver and kidney and subsequently affect the metabolism and homeostasis of uric acid, and is helpful for guiding decisions related to the breeding and production of ducks.

Allergic Identification for Ginkgo Kernel Protein in Guinea Pigs

Cai-e Wu,Jian-Ting Yang,Gong-Jian Fan,Ting-Ting Li,Zhen-Xing Tang,Fu-Liang Cao 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.3

Ginkgo biloba L. can cause allergic reactions when consumed. In this paper, an allergy test to guinea pig was investigated. Guinea pigs were sensitized with 50 mg/mL of ginkgo kernel protein orally on days 1, 3, and 5, and intraperitoneally challenged with 100mg/mL of the protein on day 7 after the last sensitization. The volume of sensitization and challenge was 0.20mL/100 g weight. The results showed the average allergy grade for guinea pigs reached four and the allergy rate was 100%. The immunoglobulin G and E levels in sera were significantly higher than those in the controls. Footpads swelled distinctly, and the passive cutaneous allergy test manifested a positive response. There were inflammatory changes in the lungs and intestines. In conclusion, the present results may indicate that gingko kernel protein has an allergenic capacity.