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Biochar is widely used as a good soil amendment, while knowledge of modified biochar application in tea garden soils contaminated by fluoride (F) and cadmium (Cd) is insufficient. The tea seedling (Camellia sinensis L.) growth assay was performed to evaluate interaction of soil Cd and F and the improving effect of aluminum trichloride-modified corn stalk biochar (Al-BC) on their speciation, phytoaccumulation and phytotoxicity. Results showed that soil F speciation ratio sequence was as follows: residual > exchangeable > organic-bound > water-soluble > Fe/Mn oxide-bound. Soil exchangeable Cd was the largest Cd speciation (>35.6%), probably due to the low pH values in the acid tea gardens. Root F contents showed a strong significant relationship with soluble F contents (r = 0.92, P < .01) and similarly root Cd highly connected with exchangeable Cd (r = 0.86, P < .01). Seedling height, fresh and dry weight, root surface area, length, and photosynthetic pigment showed different sensitivities to F or Cd oxidative stress and toxicity effects, and only root F contents significantly inversely correlated with them (r = 0.74–0.80, P < .01). The interaction of Cd and F, could influence their speciation distribution and antagonized each other in root accumulation. Meanwhile, joint simulation models showed that antagonistic effects were observed in the F and Cd mixture soils for most cases at Enshi. Biochar application reduced bioavailable F and Cd contents, and thus decreased F and Cd accumulation in tea roots and obviously alleviated toxicity effects. For instance, biochar application significantly reduced root F contents, which had 33.2% to 62.2% declines at Enshi and 39.7% to 77.2% declines at Huanggang. Meanwhile, the soil properties were improved as biochar added, with an increase in soil pH, EC, CEC and organic matter. Overall, Al-modified biochar was beneficial environmental materials for reducing both F and Cd bioavailability.

Additional file 1: Supplementary Table 1. DEGs between GC and normal samples.

Piperine, the chief alkaloid isolated from Piper nigrum, has been known to have anti-inflammatory effect. However, the effects of piperine on neuroinflammation have not been reported. In the present study, we evaluated the effects of piperine on neuroinflammation in BV2 microglia and investigated the molecular mechanism. The results showed that piperine significantly inhibited LPS-induced TNF-α, IL-6, IL-1β, and PGE2 production in BV2 cells. Western blot analysis showed that piperine dose-dependently inhibited LPS-induced NF-κB activation. Furthermore, piperine was found to amplify the expression of Nrf2 and HO-1 up-regulated by LPS. In addition, the inhibition of inflammatory mediators by piperine can be reversed by transfection with Nrf2 siRNA. In conclusion, piperine inhibited LPS-induced inflammatory response by activating Nrf2 signaling pathway. These results indicated that piperine may be a promising agent for the treatment of neurodegenerative diseases.

Based on the principle of subthreshold voltage references, a voltage reference circuitry with high PSRR is proposed in this work. In HSPICE the simulation result shows that the PSRR performance of the circuit is very good as they are 53 dB at 100 KHz, 35 dB at 100 MHz and the max is close to 92 dB, the reference voltage is 706.92plusmn1.16 mV and the average temperature coefficient is 12.9 ppm/degC at the 5 V supply voltage as well as the range of -55degC to +125degC. Moreover, the current dissipation is not more than 1.6 muA at 5 V.