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The flavan-3-ols of 10 primarily plant food byproducts, including Muscat Hamburg grape seed, hawthorn sarcocarp, litchi pericarp, cocoa bean, peanut skin, lotus seedpod, Xinyang Maojian green tea, Cinnamomi cortex, Sargentodoxa cuneata stem, and Cyperus esculentus, leaves were analyzed. Ultrahigh-performance liquid chromatography-triple quadrupole mass spectrometry was used for the analysis. Cyperus esculentus leaves contained a high amount of procyanidin B1 (198.9 mg/100 g), second only to Muscat Hamburg grape seed (292.9 mg/100 g). Unlike grape seed that contained several procyanidin B isomers with very similar retention times, C. esculentus leaves contained primarily procyanidin B1 with few isomers. Procyanidin B1 was enriched in the ethyl acetate fraction of a 70% methanol extract of C. esculentus leaves and purified at 95% purity by two runs of open column chromatography. Direct chromatography of the plant extract on octadecylsilane and Sephadex LH20 open columns improved the yield of the resultant leaf procyanidin B1 (95% purity) to 0.21‰. The present research demonstrated that the leaves of C. esculentus, byproducts of tigernut, are ideal plant sources for isolating and providing high-purity procyanidin B1. PRACTICAL APPLICATION: Procyanidin B1 has a broad range of health benefits. Cyperus esculentus is cultivated in many countries with nearly 6190 square hectares (hm

This study proposes a generic mathematical modelling and decoupling fault‐tolerant vector control for dual three‐phase permanent magnet synchronous machine (PMSM) with one phase open based on the conventional dual three‐phase voltage source inverters, accounting for the mutual coupling between two sets of three‐phase windings and the second harmonic inductance. When the dual three‐phase PMSM has one phase open, the permanent flux‐linkages are asymmetric and there are second harmonic components in the conventional synchronous reference frame (dq‐frame). Based on the proposed mathematical modelling, both permanent magnet flux‐linkages and currents become DC values in the dq‐frame, and therefore, the conventional proportional integral (PI) controller can be used to regulate the dq‐axis currents. Then, a decoupling fault‐tolerant vector control with/without a dedicated feed‐forward compensation is proposed to validate the correctness of the proposed mathematical modelling. Experimental results on a prototype dual three‐phase PMSM with one phase open show that the second harmonic dq‐axis currents can be well suppressed simply by the conventional PI controller and dedicated feed‐forward compensation. It also shows that the decoupling fault‐tolerant control based on the proposed modelling and control method has excellent dynamic performance, which is equivalent to the vector space decomposition control for the healthy machine.

The deposition of magnesium (Mg)-rich dust from magnesite mining activities has resulted in serious land degradation. However, the main factors limiting plant growth in Mg-contaminated soils are unclear. Moreover, little information is available on the remediation of Mg-contaminated soils. In this study, remediation of soils contaminated with Mg-rich dust was investigated in a pot experiment using maize as the indicator plant. There were five treatments: (i) control; (ii) leaching; (iii) application of CaCl2; (iv) leaching + CaCl2 application; and (v) application of Ca(H2PO4)2 · H2O. Soil properties and growth of maize (Zea mays L.) seedlings were measured. Leaching alone significantly decreased soluble Mg concentration. Leaching + CaCl2 application greatly increased exchangeable Ca concentration and decreased soil pH by 0·3 units. Application of CaCl2 alone increased soluble Mg concentration sharply, which directly inhibited the germination of maize seeds. Application of Ca(H2PO4)2 · H2O significantly increased the concentrations of exchangeable Ca and available phosphorus and decreased soil pH by 1·7 units. The biomass of maize seedlings increased in the order of control = leaching

To examine whether the critical leaf N ⁄ P ratios (of 14, 16) are valid to test nutrient limitation in the context of semi-arid sandy grasslands, an experiment was conducted on a Keerqin sandy grassland in North-east China to investigate the responses of plant biomass and nutrient concentrations to fertilization. Plant biomass production and leaf nutrient concentrations were measured after five consecutive years of fertilization with N (20 g N m )2 year )1 ) and ⁄ or P (10 g P2O5 m )2 year )1 ). Nitrogen fertilization increased the shoot biomass by twofold and consequently the shoot ⁄ root ratio, whereas P fertilization had little effect on either shoot biomass or shoot ⁄ root ratio. Leaf N ⁄ P ratio varied among species with an average of 5AE6 in the control, while the mean leaf N ⁄ P ratio (7AE5) under the N fertilization treatment remained below the threshold of 14. Our results suggest that the critical N ⁄ P ratio (14, 16) is not applicable as a test for nutrient limitations in the context of semi-arid, sandy grassland.

Premise of the study Microsatellite primers were developed in Prunus mongolica (Rosaceae), a relict flora endemic in arid areas of the Asian interior, to investigate the genetic diversity, phylogeography, population structure, and history of the species. Methods and results Fifty-one microsatellite loci, including di-, tri-, and tetranucelotide repeats, were identified using transcriptome sequencing and bioinformatic screening. The number of alleles ranged from seven to 11 and the levels of observed and expected heterozygosity ranged from 0.545 to 1.000 and 0.600 to 0.989, respectively. Most of the primers also amplified in a group of congeneric species (P. triloba, P. davidiana, P. persica, P. cerasifera, and P. serrulata). Conclusions This set of microsatellite loci is useful for studying the genetic diversity of P. mongolica. In addition, they can also be used to investigate the population structure, phylogeography, and landscape genetic patterns of congeneric species.