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Background: Urea is the most common nitrogen fertilizer applied to agricultural lands, and it is often treated with urease inhibitors to prevent loss of ammonia during urea hydrolysis. However, urease inhibitors like N‐(n‐butyl) thiophosphoric triamide (NBPT) are susceptible to degradation in soil. Aims: This study tested dimethyl sulfoxide, ethylene glycol and glycerol as stabilizers that could extend the inhibition effect of NBPT in a soil–plant system that received liquid urea fertilizer. Methods: We undertook a pot experiment in which two soil types (brown and black soils) were amended with liquid urea plus NBPT, with and without chemical stabilizers, then planted with bok choy. The urease activity, urea and mineral N concentration in soil and nitrogen uptake in bok choy were monitored for the next 30 days. Results: Five days after adding fertilizer, urease activity was 27%–51% lower in brown soil amended with the urea‐NBPT solutions and 32%–75% less when black soil received urea‐NBPT solution than in the control soil that received urea solution. Nearly 100% of the urea was hydrolyzed in control soil receiving urea solution after 5 days, but only 21%–41% of urea was hydrolyzed in soil amended with urea‐NBPT solution after 5 days. Stabilizers did not improve the stability of NBPT, nor did they affect the nitrogen uptake by bok choy, which was similar in the urea‐amended control soil (124 mg N pot–1) and the urea‐NBPT‐treated soil (117 mg N pot–1) during the growth period. Conclusions: Chemical stabilizers did not prolong the NBPT inhibition of urease activity, probably because the stabilizer compounds are vulnerable to degradation in well‐watered and planted soils. [ABSTRACT FROM AUTHOR]

Current anti-seizure drugs fail to control approximately 30% of epilepsies. Therefore, there is a need to develop more effective anti-seizure drugs, and medicinal plants provide an attractive source for new compounds. This study aimed to evaluate the possible anti-seizure and neuroprotective effects of neferine, an alkaloid from the lotus seed embryos of Nelumbo nucifera, in a kainic acid (KA)-induced seizure rat model and its underlying mechanisms. Rats were intraperitoneally (i.p.) administrated neferine (10 and 50 mg/kg) 30 min before KA injection (15 mg/kg, i.p.). Neferine pretreatment increased seizure latency and reduced seizure scores, prevented glutamate elevation and neuronal loss, and increased presynaptic protein synaptophysin and postsynaptic density protein 95 expression in the hippocampi of rats with KA. Neferine pretreatment also decreased glial cell activation and proinflammatory cytokine (interleukin-1β, interleukin-6, tumor necrosis factor-α) expression in the hippocampi of rats with KA. In addition, NOD-like receptor 3 (NLRP3) inflammasome, caspase-1, and interleukin-18 expression levels were decreased in the hippocampi of seizure rats pretreated with neferine. These results indicated that neferine reduced seizure severity, exerted neuroprotective effects, and ameliorated neuroinflammation in the hippocampi of KA-treated rats, possibly by inhibiting NLRP3 inflammasome activation and decreasing inflammatory cytokine secretion. Our findings highlight the potential of neferine as a therapeutic option in the treatment of epilepsy. [ABSTRACT FROM AUTHOR]

Background: Soil respiration contributes to a large quantity of carbon emissions in the forest ecosystem. In this study, the soil respiration rates at three Taiwanese forest plantations (two lowland and one mid-elevation) were investigated. We aimed to determine how soil respiration varies between lowland and mid-elevation forest plantations and identify the relative importance of biotic and abiotic factors affecting soil respiration. Results: The results showed that the temporal patterns of soil respiration rates were mainly influenced by soil temperature and soil water content, and a combined soil temperature and soil water content model explained 54-80% of the variation. However, these two factors affected soil respiration differently. Soil temperature positively contributed to soil respiration, but a bidirectional relationship between soil respiration and soil water content was revealed. Higher soil moisture content resulted in higher soil respiration rates at the lowland plantations but led to adverse effects at the mid-elevation plantation. The annual soil respiration rates were estimated as 14.3-20.0 Mg C ha year at the lowland plantations and 7.0-12.2 Mg C ha year at the mid-elevation plantation. When assembled with the findings of previous studies, the annual soil respiration rates increased with the mean annual temperature and litterfall but decreased with elevation and the mean annual precipitation. A conceptual model of the biotic and abiotic factors affecting the spatial and temporal patterns of the soil respiration rate was developed. Three determinant factors were proposed: (i) elevation, (ii) stand characteristics, and (iii) soil temperature and soil moisture. Conclusion: The results indicated that changes in temperature and precipitation significantly affect soil respiration. Because of the high variability of soil respiration, more studies and data syntheses are required to accurately predict soil respiration in Taiwanese forests. [ABSTRACT FROM AUTHOR]

Unfortunately, the original article (Huang et al. 2017) contained some errors. The Fig. 4 displayed incorrectly. The correct figure can be found below.