3,556 research outputs found
Techno-economic evaluation of reducing shielding gas consumption in GMAW whilst maintaining weld quality
A new method of supplying shielding gases in an alternating manner has been developed to enhance the efficiency of conventional gas metal arc welding (GMAW). However, the available literature on this advanced joining process is very sparse and no cost evaluation has been reported to date. In simple terms, the new method involves discretely supplying two different shielding gases to the weld pool at predetermined frequencies which creates a dynamic action within the liquid pool. In order to assess the potential benefits of this new method from a technical and cost perspective, a comparison has been drawn between the standard shielding gas composition of Ar/20%CO2, which is commonly used in UK and European shipbuilding industries for carbon steels, and a range of four different frequencies alternating between Ar/20%CO2 and helium. The beneficial effects of supplying the weld shielding gases in an alternating manner were found to provide attractive benefits for the manufacturing community. For example, the present study showed that compared with conventional GMAW, a 17 per cent reduction in total welding cost was achieved in the case of the alternating gas method and savings associated with a reduction in the extent of post-weld straightening following plate distortion were also identified. Also, the mechanical properties of the alternating case highlighted some marginal improvements in strength and Charpy impact toughness which were attributed to a more refined weld microstructure
Recommended from our members
Nanocluster-Based Ultralow-Temperature Driven Oxide Gate Dielectrics for High-Performance Organic Electronic Devices.
The development of novel dielectric materials with reliable dielectric properties and low-temperature processibility is crucial to manufacturing flexible and high-performance organic thin-film transistors (OTFTs) for next-generation roll-to-roll organic electronics. Here, we investigate the solution-based fabrication of high-k aluminum oxide (Al2O3) thin films for high-performance OTFTs. Nanocluster-based Al2O3 films fabricated by highly energetic photochemical activation, which allows low-temperature processing, are compared to the conventional nitrate-based Al2O3 films. A wide array of spectroscopic and surface analyses show that ultralow-temperature photochemical activation (6 MV/cm). Using this dielectric layer, precisely aligned microrod-shaped 2,7-dioctyl[1]benzothieno [3,2-b][1] benzothiophene (C8-BTBT) single-crystal OTFTs were fabricated via solvent vapor annealing and photochemical patterning of the sacrificial layer
iNID: An Analytical Framework for Identifying Network Models for Interplays among Developmental Signaling in Arabidopsis
Integration of internal and external cues into developmental programs is indispensable for growth and development of plants, which involve complex interplays among signaling pathways activated by the internal and external factors (IEFs). However, decoding these complex interplays is still challenging. Here, we present a web-based platform that identifies key regulators and Network models delineating Interplays among Developmental signaling (iNID) in Arabidopsis. iNID provides a comprehensive resource of (1) transcriptomes previously collected under the conditions treated with a broad spectrum of IEFs and (2) protein and genetic interactome data in Arabidopsis. In addition, iNID provides an array of tools for identifying key regulators and network models related to interplays among IEFs using transcriptome and interactome data. To demonstrate the utility of iNID, we investigated the interplays of (1) phytohormones and light and (2) phytohormones and biotic stresses. The results revealed 34 potential regulators of the interplays, some of which have not been reported in association with the interplays, and also network models that delineate the involvement of the 34 regulators in the interplays, providing novel insights into the interplays collectively defined by phytohormones, light, and biotic stresses. We then experimentally verified that BME3 and TEM1, among the selected regulators, are involved in the auxin-brassinosteroid (BR)-blue light interplay. Therefore, iNID serves as a useful tool to provide a basis for understanding interplays among IEFs.X115Ysciescopu
Inhibition of Lipopolysaccharide-Induced iNOS, COX- 2, and TNF-α Expression by Aqueous Extract of Orixa Japonica in RAW 264.7 Cells via Suppression of NF- kB Activity
Purpose: To investigate the anti-inflammatory effects of aqueous extract of Orixa japonica (AEOJ) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells.Methods: The expression of mRNA and protein using RT-PCR and Western blot analysis was investigated. The level of nitric oxide (NO) production was analyzed using Griess reaction. Release of prostaglandin E2 (PGE2) and tumor necrosis factor- (TNF-) was determined using sandwich ELISA.Results: AEOJ potently inhibited the production of nitric oxide (NO), prostaglandin E2 (PGE2), and tumor necrosis factor- (TNF-) in LPS-stimulated RAW 264.7 cells. Consistent with these findings, AEOJ wasalso found to significantly reduce LPS-induced expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), and TNF- at the transcriptional level. Additionally, AEOJ attenuated LPSinducedNF-B activity via the inhibition of IB phosphorylation and degradation. It was also found that the NF-B inhibitor N-acetyl cysteine (NAC) attenuated LPS-induced gene expression of iNOS, COX-2,and TNF-. These results indicate that AEOJ attenuates LPS-induced inflammatory mediators such as NO, PGE2, and TNF- via suppression of NF-B activity.Conclusion: These results suggest that AEOJ has a potential activity to alleviate LPS-induced inflammation
Exogenous application of plant growth regulators increased the total flavonoid content in Taraxacum officinale Wigg
The effects of plant growth regulators (PGRs) were studied on growth, total flavonoid, gibberellins (GA) and salicylic acid (SA) contents of Taraxacum officinale (dandelion), a widely used medicinal plant in Korea. All the four PGRs used; gibberellic acid (GA3), kinetin (Kn), salicylic acid (SA) and ethephon (2- chloroethylphosphonic acid) were applied at the rates of 0.5 and 1.0 mM. GA3 markedly enhanced fresh shoot weight, while 0.5 mM of kinetin application significantly enhanced dry root mass as compared tocontrol. SA enhanced both shoot and root attributes, while ethephon decreased plant growth. Endogenous bioactive GA1 and GA4 content and SA content enhanced with the application of GA3, SA and kinetin, but declined with ethephon. The flavonoid content of dandelion significantly increased with SA treatment, but was not altered with the application of other PGRs. The current study demonstrated the favorable effect of GA3, kinetin and SA on growth, bioactive GAs, SA and flavonoid contents of dandelion. These investigations offered interesting information as PGRs were never tested for plant growth and development of dandelion. It also reports the presence of both early C-13 hydroxylation and non C-13 hydroxylation pathways of GA biosynthesis in dandelion for the first time
Methanol Extract of Myelophycus caespitosus Inhibits the Inflammatory Response in Lipopolysaccharidestimulated BV2 Microglial Cells by Downregulating NF-kB via Inhibition of the Akt Signaling Pathway
Purpose: To determine whether the methanol extract of Myelophycus caespitosus (MEMC) downregulates the expression of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated BV2 microglial cells.Methods: Reverse transcription-polymerase chain reaction (RT-PCR) together with Western blot analysis was used to evaluate the expression of pro-inflammatory mediators such as nitric oxide (NO) and prostaglandin E2(PGE2) as well as their regulatory genes such as inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), in LPS-stimulated BV2 microglial cells. The level of NO production was analyzed using Griess reaction.The release of PGE2 was determined using sandwich enzyme-linked immunosorbent assay. The DNA-binding activity of nuclear factor-êB (NF-êB) was measured by electrophoretic mobility shift assay.Results: MEMC inhibited LPS-induced pro-inflammatory mediators, NO and PGE2, as well as their respective genes, iNOS and COX-2, at both protein and mRNA levels, without any significant cytotoxicity. Treatment withMEMC also substantially reduced the LPS-induced DNA-binding activity of NF-êB and nuclear translocation of NF-êB subunits p65 and p50 via the inhibition of IêBá phosphorylation and degradation. MEMC promoteddephosphorylation of Akt that subsequently suppressed the DNA-binding activity of NF-êB in LPS-stimulated BV2 microglial cells.Conclusion: Collectively, these data suggest that MEMC attenuates expression of pro-inflammatory mediators such as NO and PGE2 by suppression of their regulatory genes through the inhibition of Aktmediated NF-êB activity.Keywords: Myelophycus caespitosus, Nitric oxide, Prostaglandin E2, Nuclear factor-êB
Aqueous Extract of Oldenlandia diffusa Suppresses LPS-Induced iNOS, COX-2 and TNF-α Expression in RAW 264.7 Cells via the NF-κB Activity
Purpose: To elucidate the anti-inflammatory mechanisms of aqueous extract of Oldenlandia diffusa (AEOD) in LPS-stimulated RAW 264.7 cells.Methods: We evaluated the mRNA and protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and tumor necrosis factor (TNF)-α using RT-PCR and Western blot analyses. Expressions of IκBα, phospho-IκBα and p65 were analyzed by Western blot analysis. The level of nitric oxide (NO) production was analyzed using Griess reaction. The release of prostaglandin E2 (PGE2) and tumor necrosis factor (TNF)-α was determined using sandwich ELISA.Results: AEOD significantly suppressed nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells without direct cytotoxicity. AEOD decreased the production of prostaglandin E2 (PGE2) and TNF-α in LPS-stimulated RAW 264.7 cells. LPS-induced mRNA and protein expression of iNOS, COX-2 and TNF-α were attenuated by treatment with AEOD. These data imply that AEOD tightly regulates the expression of these inflammatory mediators at the transcriptional level. Therefore, we determined the effects of AEOD on nuclear factor-κB (NF-κB) activity, which has been considered to be a potential transcriptional factor for regulating the expression of iNOS, COX-2 and TNF-α. As expected, AEOD suppressed the LPS-induced degradation and phosphorylation of IκBα and sustained the expression of p65 in the cytosol. Furthermore, AEOD substantially inhibited the LPS-induced DNA binding activity of NF-κB. These data show that AEOD may control NO, PGE2 and TNF-α production via the suppression of NF-κB activity.Conclusion: Our results suggest that AEOD has a high potential activity for regulating LPS-induced inflammation.Keywords: Oldenlandia diffusa, NO, iNOS, COX-2, PGE2, TNF-α, NF-κ
Methanol Extract of Polyopes lancifolius Inhibits the Expression of Pro-inflammatory Mediators in LPSstimulated BV2 Microglia Cells via Downregulation of the NF-κB Pathway
Purpose: This study is aimed at identifying the anti-inflammatory mechanisms of a methanol extract of Polyopes lancifolius (MEPL) in lipopolysaccharide (LPS)-stimulated BV2 microglia cells.Methods: The expression of mRNA and protein were investigated RT-PCR and western blot analyses in LPS-stimulated BV2 microglial cells. The level of nitric oxide (NO) production was analyzed using Griess reaction. The release of prostaglandin E2 (PGE2) and tumor necrosis factor-α (TNF-α) were determined using sandwich ELISA. NF-κB activation was detected using EMSA methods.Results: MEPL significantly suppressed NO production in LPS-stimulated BV2 cells without any cytotoxicity. The results also indicate that MEPL decreased the production of PGE2 and TNF-α in LPSstimulated BV2 cells. Furthermore, pretreatment with MEPL resulted in a downregulation of LPSinduced mRNA and protein expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and TNF-α. Investigation of the effect of MEPL on nuclear factor-κB (NF-κB) activity, which is a potential transcriptional factor for regulating inflammatory genes such as iNOS, COX-2 and TNF-α, showed that MEPL substantially inhibited the LPS-induced DNA-binding activity of NF-κB. MEPL also suppressed the LPS-induced degradation and phosphorylation of I&kappaBα, and it consequently blocked p65 translocation from the cytosol to the nucleus.Conclusion: These data show that MEPL may regulate LPS-induced NO, PGE2, and TNF-α production by suppressing NF-κB activity.Keywords: Polyopes lancifolius, Nitric oxide, Prostaglandin E2, Tumor necrosis factor-α, Nuclear factor-κ
Influence of prohexadione-calcium, trinexapac-ethyl and hexaconazole on lodging characteristic and gibberellin biosynthesis of rice (Oryza sativa L.)
We investigated the influence of prohexadione-calcium (Pro-Ca), trinexapac-ethyl (TNE) and hexaconazole (HX) on lodging and gibberellin (GA) biosynthesis pathway of rice cultivar, Hwayeongbyeo. It was observed that these novel synthetic growth retardants suppressed lodging of rice under field conditions through blocking GA biosynthesis pathway. These growth retarding chemicals were applied at basic (20 uM) and elevated (40 uM) rates either 10 days before heading (10 DBH) or 5 days before heading (5 DBH). We found that Pro-Ca, TNE and their combined application (Pro-Ca + TNE) were most effective in decreasing rice length and lodging index, when applied at 10 DBH. Similarly, the endogenous bioactive GA1 contents of rice significantly declined with application of Pro-Ca, TNE and Pro-Ca + TNE, while they were less effected by basic and elevated rates of HX as compared to the control. The growth retardants were more effective in decreasing rice lodging and blocking GA biosynthesis when applied in elevated rates. The levels of the endogenous gibberellins in rice shoots were measured by GC/MS-SIM using 2H2-labeled gibberellins as internal standards. Effect of these synthetic chemicals on growth and GA inhibition were stronger initially but eroded rapidly under field conditions. It was thus concluded that Pro-Ca and TNE were most effective in reducing plant length and suppressing lodging of rice crop under field conditions, where lodging is a major constraint to higher productivity.Key words: Growth retardants, plant growth, gibberellin biosynthesis, lodging index, rice
Inhibition of Nitric Oxide and Prostaglandin E2 Expression by Methanol Extract of Polyopes affinis in Lipopolysaccharide-stimulated BV2 Microglial Cells through Suppression of Akt-dependent NF-kB Activity and MAPK Pathway
Purpose: To determine whether the methanol extract of Polyopes affinis (MEPA) down-regulates the expression of pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated BV2 microglial cells.Methods: The production of nitric oxide (NO) and prostaglandin E2 (PGE2) was measured by the Griess reagents and enzyme-linked immunosorbent assay (ELISA), respectively. Expression levels of mRNA and protein in LPS-stimulated BV2 microglial cells were assessed by reverse transcription-polymerase (RT-PCR) and Western blot analysis. Activation of nuclear factor-êB (NF-êB) was detected by electrophoretic mobility shift assay (EMSA).Results: MEPA inhibited the expression of LPS-induced pro-inflammatory mediators, NO and PGE2, as well as their respective genes, iNOS and COX-2, at both protein and mRNA levels, without any accompanying cytotoxicity. Moreover, treatment with MEPA significantly suppressed the LPS-induced DNA-binding activity of NF-êB, which is known as a main transcription factor for the regulation of proinflammatory genes, as well as the nuclear translocation of its subunit p65 and p50, by degrading IêBá.MEPA increased Akt dephosphorylation which leads to suppression of the DNA-binding activity of NF-kB in LPS-stimulated BV2 microglial cells and suppressed phosphorylation of ERK and JNK, which are involved in the mitogen-activated protein kinase (MAPK) signaling pathway for regulating proinflammatory genes.Conclusion: Our results indicate that MEPA down-regulates pro-inflammatory mediators such as NO and PGE2 by suppressing Akt-dependent NF-êB activity as well as phosphorylation of ERK and JNK inLPS-stimulated BV2 microglial cells.Keywords: Polyopes affinis, Nitric oxide, Prostaglandin E2, Nuclear factor-k
- …