730 research outputs found

    Development of a trench cutting re-mixing deep wall method model test device

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    The trench cutting re-mixing deep wall (TRD) is a new type of underground waterproof curtain. Mixing uniformity is the key index affecting the efficiency and quality of this method. However, because of many influencing factors, existing theories cannot be used to express the relationship between various factors and mixing uniformity. By analyzing the cutting and mixing process of the TRD method, the main factors affecting the uniformity of the mixing were obtained. A model test device was designed and manufactured, based on Buckingham's pi theorem. The validity of the model test device was verified through a comparative analysis of model and field test results. The model test device was demonstrated to be able to simulate the mixing process of the TRD method. The results provide guidance for promotion and better application of the TRD method

    Antioxidant phenolics from Broussonetia papyrifera fruits

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    Fractionation of the EtOH extract from the fruits of Broussonetia papyrifera led to the isolation of 15 phenolic compounds (1–15). Their structures were identified using spectroscopic methods. Among these compounds, 1 and 2 are new and 3–15 were isolated from this plant for the first time. Antioxidant activities of compounds 2–15 against H2O2-induced injury in SY5Y cells and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities were evaluated

    Effect of Astragalus polysaccharide supplementation on growth performance and plasma parameters of weaned piglets under commercial condition

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    The aim of this study was to evaluate the effect of Astragalus polysaccharide (APS) supplementation on the growth performance, plasma biochemical parameters, and plasma immune and antioxidant indexes of weaned piglets in a commercial swine farm. A total of 120 piglets weaned at 22 days and allocated to 2 groups, and fed a basal diet either without (CTR) or with 200 mg/kg of APS in a local commercial farm for a 42-d experiment. At end of the trial, one piglet from each pen was selected for blood sampling. The results showed that dietary APS decreased the feed conversion ratio (FCR) compared to the CTR group from day 14 to day 28 and day 0 to day 42 (P = 0.08 and 0.02, respectively). In addition, supplementation of APS had the tendency to increase the plasma superoxide dismutase activity and IgG content of piglets compared to the CTR group on day 42 (P = 0.06 and 0.09, respectively). Results in this study suggested that dietary APS might have a beneficial effect on growth performance and health status of weaned piglets under the commercial condition

    Effects of Spermidine on Cell Proliferation, Migration, and Inflammatory Response in Porcine Enterocytes.

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    peer reviewed[en] BACKGROUND: Polyamines have been demonstrated to be beneficial to porcine intestinal development. Our previous study showed that putrescine mitigates intestinal atrophy in weanling piglets and suppresses inflammatory response in porcine intestinal epithelial cells, it is still unknown the role of spermidine in mediating putrescine function. OBJECTIVE: The current study aimed to investigate the effect of spermidine on the proliferation, migration, and inflammatory response in porcine intestinal epithelial cells (IPEC-J2 cell line). METHODS: The effects of spermidine on proliferation and migration of IPEC-J2 cells were measured. Difluoromethyl ornithine (DFMO) and diethylglyoxal bis (guanylhydrazone) (DEGBG) were used to block the production of putrescine and spermidine, respectively. A cell inflammation model was established with lipopolysaccharides (LPS) stimulation. Gene expression and protein abundance were determined by real-time quantitative PCR and western blotting, respectively. RESULT: Spermidine significantly enhanced cell proliferation in DFMO (or/and) DEGBG treated IPEC-J2 cells (p 0.05). Similarly, spermidine but not putrescine significantly elevated the rate of migration in DEGBG treated IPEC-J2 cells (p < 0.05). Spermidine deprivation by DEGBG dramatically enhanced mRNA abundance of pro-inflammatory cytokines IL-8, IL-6, and TNF-α (p < 0.05), and the addition of spermidine attenuated excessive expression of those inflammatory pro-inflammatory cytokines, moreover, spermidine but not putrescine suppressed the phosphorylation of NF-κB induced by DEGBG. Spermidine supplementation also significantly suppressed LPS-induced the expression of TNF-α. CONCLUSIONS: The present study highlights a novel insight that putrescine may be converted into spermidine to modulate cell proliferation, migration, and inflammatory response on porcine enterocytes

    Effects of deformation temperature on edge crack characteristics and mechanical properties of as-cast aluminum alloy

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    In this study, the rolling technique of aluminum alloy was investigated, and the effects of deformation temperature on the edge cracks and mechanical properties of aluminum alloy were studied through a hot compression experiment on high magnesium aluminum alloy. Based on the test, DEFORM-3D software was introduced to optimize the selection of the influence conditions of the experiment. The research results suggested that the crack length of the as-cast aluminum alloy samples decreased with the increase of temperature when the deformation temperature was between 300 °C and 450 °C; the tensile strength and elongation after fracture increased with the increase of temperature when the deformation temperature was between 300 °C and 500 °C. Therefore it is concluded that the cracks of high magnesium aluminum alloy can be reduced through controlling deformation temperature, which provides an idea for the optimization of aluminium alloy

    Metabolic engineering of Escherichia coli for the biosynthesis of alpha-pinene

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    Background: alpha-Pinene is an important natural product that is widely used in flavorings, fragrances, medicines, fine chemicals and high-density renewable fuels. Currently, alpha-Pinene used in industry is mainly produced either by tapping trees (gum turpentine) or as a byproduct of paper pulping (crude sulfate turpentine, CST). However, the extraction of it from trees is tedious and inefficient and requires substantial expenditure of natural resources. Therefore, it is necessary to seek sustainable technologies for alpha-pinene production

    ETHANOLIC EXTRACT OF ACONITI BRACHYPODI RADIX ATTENUATES NOCICEPTIVE PAIN PROBABLY VIA INHIBITION OF VOLTAGE-DEPENDENT NA+ CHANNEL

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    Aconiti Brachypodi Radix, belonging to the genus of Aconitum (Family Ranunculaceae), are used clinically as anti-rheumatic, anti-inflammatory and anti-nociceptive in traditional medicine of China. However, its mechanism and influence on nociceptive threshold are unknown and need further investigation. The analgesic effects of ethanolic extract of Aconiti Brachypodi Radix (EABR) were thus studied in vivo and in vitro. Three pain models in mice were used to assess the effect of EABR on nociceptive threshold. In vitro study was conducted to clarify the modulation of the extract on the tetrodotoxin-sensitive (TTX-S) sodium currents in rat’s dorsal root ganglion (DRG) neurons using whole-cell patch clamp technique. The results showed that EABR (5-20 mg/kg, i.g.) could produce dose-dependent analgesic effect on hot-plate tests as well as writhing response induced by acetic acid. In addition, administration of 2.5-10 mg/kg EABR (i.g.) caused significant decrease in pain responses in the first and second phases of formalin test without altering the PGE2 production in the hind paw of the mice. Moreover, EABR (10 μg/ml -1 mg/ml) could suppress TTX-S voltage-gated sodium currents in a dose-dependent way, indicating the underlying electrophysiological mechanism of the analgesic effect of the folk plant medicine. Collectively, our results indicated that EABR has analgesic property in three pain models and useful influence on TTX-S sodium currents in DRG neurons, suggesting that the interference with pain messages caused by the modulation of EABR on TTX-S sodium currents in DRG neurones may explain some of its analgesic effect
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