The Promotion/Inhibition of the Seepage Transport of Copper Ions by Suspension-Colloidal Particles with Wide Size Gradation

Sand column tests were conducted to investigate the seepage transport of silicon powders (SPs) with two wide particle size ranges (30-2000 nm and 2-70 μm), including the cotransport of SPs and copper ions. The results show that the graded large-scale SP has an obvious inhibiting influence on the transport of copper ions. In contrast, in the presence of the graded small-scale SP, the concentration of copper ions in the effluent tends to increase; i.e., there appears to be a promoting effect. However, after a long transport distance, the presence of SPs, regardless of particle size, has an overall retarding effect on heavy metal pollutants (e.g., copper ions). The promoting effect of the increase in seepage velocity on the concentration of copper ions in the effluent is greater with the graded large-scale SPs than with the graded small-scale SPs. In terms of the microstructural characteristics by metallographic microscopy, the average particle size of the deposited graded small-scale SPs is almost constant at different transport distances, while that of the deposited graded large-scale SPs tend to decrease significantly with increasing transport distance; i.e., notable bed filtration is exhibited in the latter case. This physical mechanism also determines the sequence and rate of the retarding effect of SPs on heavy metal ions under seepage flow.

High Summer Temperatures Have No Role in Breaking Physical Dormancy Among Seeds of Fireprone Cistaceae: A Reinterpretation of Luna (2020)

In a unique study, Luna (2020) examined the viability and germination of 12 hard-seeded Cistaceae in the Mediterranean Basin by alternating a prolonged summer-type-temperature (50/20°C at 12 h cycles) treatment with a fire-type heat pulse. A re-analysis of their data shows that the summer treatment applied before the heat pulse was superfluous as similar high levels of germination under ambient conditions were attained with the heat pulse only. The abundance of hard seeds remaining when the summer treatment was applied after the heat pulse is better explained by ungerminated seeds having become hard again rather than not responding, i.e., showing secondary physical dormancy, and thus became ‘desensitized’ to their environment. While this response is adaptive, such a retarding effect will be limited in practice as most fires are expected in autumn, at least historically, and are thus close to the start of optimal winter conditions for germination. Future studies should concentrate on the fate of the water-gap plug during such alternating treatments and also ensure that realistic summer temperature regimes are used.

GA/ABA Antagonism in the Physiology of Seed Germination in the Recalcitrant and Vulnerable Tree- Vateria indica L.

Background: Seed recalcitrance is a major problem associated with many tropical plants, limiting their natural regeneration. Vateria indica L. is a vulnerable and endemic tree species in South-Western Ghats of India, which is also recalcitrant. ABA and gibberellins are the most important plant hormones required for seed germination. It is the balance between ABA and GA which is responsible for desiccation tolerance in orthodox seeds. Exogenous hormones pretreatment has been also reported to influence seed germination. But such studies had been sparsely done in the case of recalcitrant seeds. This study aims to find out whether GA/ABA antagonism in recalcitrant plants is operating in the same way, like that in the orthodox seeds.Methods: The effect of the exogenous pre-soaking application of phytohormones viz. GA3 and ABA individually as well as their combinations on seed germination and growth of Vateria indica L. were carried out in the present work. The seeds were collected from April to July 2018 and the experiment was designed at Post Graduate and Research Department of Botany, Government College for Women, Thiruvananthapuram. When different concentrations of each phytohormone were externally given to the seeds, ABA reduced the germination and growth in almost all the concentrations. But GA3 gave better results. When combinations of GA3 and ABA were used, germination was poor in the sample where ABA was more than GA3, But in samples with same concentrations of both the hormones and with more GA3 gave better results. Result: This study clearly showed that GA3 when given externally along with ABA, might have affected the endogenous ABA in this recalcitrant seed and suppressed its retarding effect. Thus ABA/GA antagonism is working out, here, in the same way as in orthodox seeds. Since the germination of recalcitrant seeds is a less investigated area, the present study will form a basis and a lot more for further such studies.

Retarding effect of dietary fibers from bamboo shoot (Phyllostachys edulis) on hyperlipidemic rats induced by high-fat diet

The effects of administration of bamboo shoot (Phyllostachys edulis) dietary fiber (BSDF) on high-fat diet (HDF) induced hyperlipidemia were studied with SD rats model. Results indicated that the body weight...

Staling of sponge cakes with added emulsifiers

The effect of three types of emulsifiers (polyglycerol monostearate ester – E475, sucrose stearate ester – E473 and modified inulin palmitate ester – HP-25) on the starch retrogradation in sponge cake (SC) during storage was investigated. The method of differential scanning calorimetry (DSC) was applied to determine the changes in the starch retrogradation during the staling process. The retrogradation temperature and the enthalpy of the endothermic transition decreased when emulsifiers were added. The lowest values of the enthalpy for the whole storage period were found for SC with 1% HP-25. The methods of differential thermal analysis (DTA) and thermogravimetry analysis (TGA) showed significantly bigger (1.43 times) amount of strongly bound water in the crumb of the SC with E475 and HP-25 in comparison to the control sample on the sixth day of storage. Based on our results, emulsifiers possessed retarding effect on the starch retrogradation and extend the shelf-life of the SC.

Mesenchymal stem cells reverse EMT process through blocking the activation of NF-κB and Hedgehog pathways in LPS-induced acute lung injury

Acute lung injury (ALI) is a pulmonary disorder, which can result in fibrosis of the lung tissues. Recently, mesenchymal stem cell (MSC) has become a novel therapeutic method for ALI. However, the potential mechanism by which MSC regulates the progression of ALI remains blurry. The present study focused on investigating the mechanism underneath MSC-reversed lung injury and fibrosis. At first, we determined that coculture with MSC led to the inactivation of NF-κB signaling and therefore suppressed hedgehog pathway in LPS-treated MLE-12 cells. Besides, we confirmed that MSC-exosomes were responsible for the inhibition of EMT process in LPS-treated MLE-12 cells through transmitting miRNAs. Mechanism investigation revealed that MSC-exosome transmitted miR-182-5p and miR-23a-3p into LPS-treated MLE-12 cells to, respectively, target Ikbkb and Usp5. Of note, Usp5 interacted with IKKβ to hamper IKKβ ubiquitination. Moreover, co-inhibition of miR-182-5p and miR-23a-3p offset the suppression of MSC on EMT process in LPS-treated MLE-12 cells as well as in LPS-injured lungs of mice. Besides, the retarding effect of MSC on p65 nuclear translocation was also counteracted after co-inhibiting miR-182-5p and miR-23a-3p, both in vitro and in vivo. In summary, MSC-exosome transmitted miR-23a-3p and miR-182-5p reversed the progression of LPS-induced lung injury and fibrosis through inhibiting NF-κB and hedgehog pathways via silencing Ikbkb and destabilizing IKKβ.

Influences and Mechanisms of Nano-C-S-H Gel Addition on Fresh Properties of the Cement-Based Materials with Sucrose as Retarder

Influences and mechanisms of chemically synthesized nano-C-S-H gel addition on fresh properties of the cement-based materials with sucrose as a retarder were investigated in this study. The results showed that the flow value of the fresh cement paste was gradually but slightly reduced with increasing nano-C-S-H gel addition due to its fibrous but well-dispersed characteristic in both water and cement paste. The semi-adiabatic calorimetry testing results verified that incorporation of nano-C-S-H gel could greatly mitigate the retarding effect of sucrose on cement hydration. The total organic carbon (TOC) indicated that the addition of the nano-C-S-H gel helps to reduce adsorption of the sucrose molecules into the protective layer, thus the semi-permeability of the protective layer was less reduced and that is why the addition of the nano-C-S-H gel can mitigate the retardation caused by the sucrose. Through XRD analysis, it was found that the CH crystals are more prone to grow along the (0001) plane with larger size in the paste with nano-C-S-H addition before the induction period starts, because the C-S-H nanoparticles can form 3D network to slow down the diffusion rate of the released ions and eliminate the convection in the paste, thus suppress the 3D nucleation and growth of the CH crystals. The XRD analysis also indicated a refinement of the ettringite crystals in the paste with sucrose addition, but introduction of nano-C-S-H gel did not show further refinement, which was also verified by the SEM observation.