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Different cadmium (Cd)-accumulated rice genotypes (Erjiunan 1 and Fupin 36) were used to explore the effect of rice rhizosphere aeration on Cd uptake and accumulation. Aeration in the nutrient solution influenced the agronomic characteristics induced by Cd-stress, such as the increases of rice root length and root vigor, but the reductions of plant height and shoot dry weight. Aeration also alleviated the decreasing effects of Cd stress on antioxidant enzyme activities and soluble protein, malonaldehyde and nicotianamine contents in rice. Moreover, with aeration treatment, the accumulation and bioavailability of metal elements changed significantly, with a Cd increase and an Fe reduction in both rice genotypes. In addition, at the molecular level, aeration upregulated the expression of Fe-inducible genes (such as OsIRT1, OsNRAMP1, OsYSL15 and OsNAS3). Furthermore, as a Cd2+/Fe2+ transporter, the high transcription level of OsNRAMP1 can elevate the Cd uptake and translocation in rice due to the Fe reduction caused by aeration and Cd-exposure, which indicated that OsNRAMP1 might play a crucial role in the effect of aeration on Cd uptake and accumulation.

Triclabendazole (TCB) is widely used for prevention and treatment of parasitic infections in animals. Improper use can result in drug residues in animal tissues and cause health problems to humans through consumption. A simple and reliable analytical method for the determination of TCB and its metabolites in bovine and goat muscle using liquid chromatography–tandem mass spectrometry (LC–MS/MS) was developed and validated. Analytes were extracted using acetonitrile and purified using enhanced matrix removal cartridge. Chromatographic separation was carried out on a BEH Shield RP18 column. The analytes were detected in positive‐mode electrospray ionization mass spectrometry using multiple reaction monitoring. Average recoveries of 96.1%–105.6% with coefficients of variation of 1.9%–8.4% were obtained at fortification levels of 0.5, 2.5, 25, and 50 μg/kg for TCB and 5.0, 25, 250, and 500 μg/kg for its metabolites (triclabendazole sulfoxide, triclabendazole sulfone, and keto‐TCB). A good linear regression was obtained with the mixed standard solutions in the range of 0.05–20 μg/L for TCB and 0.5–200 μg/L for its metabolites. The limit of quantification and limit of detection ranged from 0.05 to 0.75 μg/kg and from 0.1 to 1.5 μg/kg, respectively. Moreover, this method was successfully applied to 33 real samples. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of decentralized safety control (DSC) of constrained interconnected nonlinear safety-critical systems under reinforcement learning strategies, where asymmetric input constraints and security constraints are considered. To begin with, improved performance functions associated with the actuator estimates for each auxiliary subsystem are constructed. Then, the decentralized control problem with security constraints and asymmetric input constraints is transformed into an equivalent decentralized control problem with asymmetric input constraints using the barrier function. This approach ensures that safety-critical systems operate and learn optimal DSC policies within their safe global domains. Then, the optimal control strategy is shown to ensure that the entire system is uniformly ultimately bounded (UUB). In addition, all signals in the closed-loop auxiliary subsystem, based on Lyapunov theory, are uniformly ultimately bounded, and the effectiveness of the designed method is verified by practical simulation. [ABSTRACT FROM AUTHOR]

Over the past few decades of rapid development, China has always attached great importance to the redevelopment of rural areas. Since the 19th National Congress of the Communist Party of China, the rural revitalization strategy proposed at the meeting has always received extensive attention. In 2019, the Chinese central government released a document on its rural revitalization strategy. In the document, Guizhou Province was listed as a key area to receive focus on pursuing rural revitalization. Meanwhile, the Guizhou government also formulated The Implementation Opinions on the People's Government of Guizhou Province's Rural Revitalization Strategy. The aim of this paper is to try to establish a model according to the rural revitalization strategy proposed by the Guizhou government and extracts the main influencing factors from its analysis. Through the analysis of the data collected during the process of the rural revitalization, the paper undertakes a deep analysis of the evaluation and studies an optimized approach to the revitalization to provide a referenced review for other villages. [ABSTRACT FROM AUTHOR]

SUMMARY: The initiation and development of storage roots (SRs) are intricately regulated by a transcriptional regulatory network. One key challenge is to accurately pinpoint the tipping point during the transition from pre‐swelling to SRs and to identify the core regulators governing such a critical transition. To solve this problem, we performed a dynamic network biomarker (DNB) analysis of transcriptomic dynamics during root development in Ipomoea batatas (sweet potato). First, our analysis identified stage‐specific expression patterns for a significant proportion (>9%) of the sweet potato genes and unraveled the chronology of events that happen at the early and later stages of root development. Then, the results showed that different root developmental stages can be depicted by co‐expressed modules of sweet potato genes. Moreover, we identified the key components and transcriptional regulatory network that determine root development. Furthermore, through DNB analysis an early stage, with a root diameter of 3.5 mm, was identified as the critical period of SR swelling initiation, which is consistent with morphological and metabolic changes. In particular, we identified a NAM/ATAF/CUC (NAC) domain transcription factor, IbNAC083, as a core regulator of this initiation in the DNB‐associated network. Further analyses and experiments showed that IbNAC083, along with its associated differentially expressed genes, induced dysfunction of metabolism processes, including the biosynthesis of lignin, flavonol and starch, thus leading to the transition to swelling roots. Significance Statement: The initiation and development of storage roots (SRs) are intricately regulated by a complex regulatory network, and most studies just focus on static molecular biomarkers. In this study, based on our gene expression profiles of sweet potato roots at different developmental stages, we studied the molecular mechanisms of SR development from the perspectives of dynamics and network, and identified the tipping point and key regulators of the SR swelling process by the dynamic network biomarker method. [ABSTRACT FROM AUTHOR]

An analytical method was established to simultaneously determine prochloraz and three metabolites N-propyl-N-[2-(2,4,6-trichlorophenoxy)ethyl] urea(BTS44595), N-formyl-N-propyl-N-[2-(2,4,6-trichlorophenoxy)ethyl] urea(BTS44596), and 2,4,6-trichlorophenol(BTS45186) in fruits and vegetables. The analysis was performed by liquid chromatography – tandem mass spectrometry (LC-MS/MS) in the positive and negative ion-switching multiple reaction modes (MRM). The analytes were extracted using acetonitrile. The extract was further purified by dispersive solid phase extraction. The linearity of the matrix-matched calibration curves was verified with correlation coefficients (r) greater than 0.9975. Recoveries in fruits and vegetables were conducted at four appropriate concentrations. The average recoveries of the method ranged from 80% to 105%, and the relative standard deviations were less than 15%. The limits of detection and quantification of the analytes in fruits and vegetables were from 0.1 to 1 µg/kg and 0.5 to 5 µg/kg, respectively. The method was validated and demonstrated to be suitable for the determination of prochloraz and three metabolites in fruits and vegetables. [ABSTRACT FROM AUTHOR]

Aim: Immune-related lncRNA may influence osteoarthritis (OA) susceptibility. We conducted this study to assess whether the genetic variants in several immune-related lncRNA influence OA susceptibility. Methods: The current research genotyped four SNPs in 306 OA patients and 316 healthy controls, including PRNCR1 rs7463708, PRNCR1 rs1456315, PRNCR1 rs16901946 and KIF13B1 rs643472, to investigate their associations with OA susceptibility. Results: We identified that PRNCR1 rs1456315 was associated with OA susceptibility in Chinese Han population (recessive model: odds ratio = 2.24; 95% CI: 1.05-4.81; additive model: odds ratio = 1.36; 95% CI: 1.03-1.80). Conclusion: Individuals with PRNCR1 rs1456315 mutant G allele were more likely to suffer from OA in Chinese Han population. [ABSTRACT FROM AUTHOR]

Iron (Fe) deficiency is one of the most common micronutrient deficiencies limiting crop production globally, especially in arid regions because of decreased availability of iron in alkaline soils. Sweet potato [ Ipomoea batatas (L.) Lam.] grows well in arid regions and is tolerant to Fe deficiency. Here, we report that the transcription of type I H+-pyrophosphatase (H+- PPase) gene Ib VP1 in sweet potato plants was strongly induced by Fe deficiency and auxin in hydroponics, improving Fe acquisition via increased rhizosphere acidification and auxin regulation. When overexpressed, transgenic plants show higher pyrophosphate hydrolysis and plasma membrane H+- ATPase activity compared with the wild type, leading to increased rhizosphere acidification. The Ib VP1-overexpressing plants showed better growth, including enlarged root systems, under Fe-sufficient or Fe-deficient conditions. Increased ferric precipitation and ferric chelate reductase activity in the roots of transgenic lines indicate improved iron uptake, which is also confirmed by increased Fe content and up-regulation of Fe uptake genes, e.g. FRO2, IRT1 and FIT. Carbohydrate metabolism is significantly affected in the transgenic lines, showing increased sugar and starch content associated with the increased expression of AGPase and SUT1 genes and the decrease in β-amylase gene expression. Improved antioxidant capacities were also detected in the transgenic plants, which showed reduced H2O2 accumulation associated with up-regulated ROS-scavenging activity. Therefore, H+- PPase plays a key role in the response to Fe deficiency by sweet potato and effectively improves the Fe acquisition by overexpressing Ib VP1 in crops cultivated in micronutrient-deficient soils. [ABSTRACT FROM AUTHOR]

Dicyclanil is a toxic, pyrimidine-derived insect growth regulator used in veterinary medicine for the prevention of myiasis. A competitive indirect enzyme-linked immunosorbent assay was developed firstly for the determination of dicyclanil in animal tissue. The antigen was prepared using the glutaraldehyde method and polyclonal antibodies were obtained by immunizing rabbits with a dicyclanil-bovine serum albumin conjugate. The antibody obtained was specific for dicyclanil with an IC50of 9 ng/mL. Recoveries from sheep tissue and liquid milk were in the range of 52.5–72.4%, with coefficients of variation between 4.7% and 11.9%. The results were further confirmed by high performance liquid chromatography–tandem mass spectrometry. [ABSTRACT FROM PUBLISHER]

The residual behaviors and dietary risk probability of 12 pesticides in Dendrobium officinale Kimura et Migo cultivated at two representative locations under green house conditions were investigated using liquid chromatography-tandem mass spectrometry. Field trials showed that the half-lives of 12 pesticides ranged from 0.9 to 14.4 days in fresh D. officinale stems. Based on maximum residue levels (MRLs), the ultimate residues of imidacloprid, dimethomorph, metalaxyl, tebuconazole, and cyazofamid at a pre-harvest interval (PHI) of 28 days were within acceptable limits. For abamectin, indoxacarb, and difenoconazole, 35-day PHIs were needed. The PHIs of trifloxystrobin and fluopyram were 42 days, the time required for their residues to be reduced to an MRL of 4 mg/kg. The chronic and acute risk quotients of target pesticides at PHIs of 28–42 days were below 5.929% and 0.532%, respectively, showing that the evaluated D. officinale exhibited an acceptably low dietary risk to the general population. • Determination of twelve pesticides in Dendrobium officinale UPLC-MS/MS. • The fate of twelve pesticides in Dendrobium officinale has been investigated. • The pre-harvest intervals of these pesticides have been proposed. • The potential health risks were not significant based on dietary risk assessment. [ABSTRACT FROM AUTHOR]

CRISPR/Cas9-mediated genome editing is a powerful technology that has been used for the genetic modification of a number of crop species. In order to evaluate the efficacy of CRISPR/Cas9 technology in the root crop, sweet potato (Ipomoea batatas), two starch biosynthetic pathway genes, IbGBSSI (encoding granule-bound starch synthase I), and IbSBEII (encoding starch branching enzyme II), were targeted in the starch-type cultivar Xushu22 and carotenoid-rich cultivar Taizhong6. I. batatas was transformed using a binary vector, in which the Cas9 gene is driven by the Arabidopsis AtUBQ promoter and the guide RNA is controlled by the Arabidopsis AtU6 promoter. A total of 72 Xushu22 and 35 Taizhong6 transgenic lines were generated and analyzed for mutations. The mutation efficiency was 62–92% with multi-allelic mutations in both cultivars. Most of the mutations were nucleotide substitutions that lead to amino acid changes and, less frequently, stop codons. In addition, short nucleotide insertions or deletions were also found in both IbGBSSI and IbSBEII. Furthermore, a 2658 bp deletion was found in one IbSBEII transgenic line. The total starch contents were not significantly changed in IbGBSSI- and IbSBEII-knockout transgenic lines compared to the wild-type control. However, in the allopolyploid sweet potato, the IbGBSSI-knockout reduced, while the IbSBEII-knockout increased, the amylose percentage. Our results demonstrate that CRISPR/Cas9 technology is an effective tool for the improvement of starch qualities in sweet potato and breeding of polyploid root crops. [ABSTRACT FROM AUTHOR]

Abstract: The fate of pymetrozine was studied in rice field ecosystem, and a simple and reliable analytical method for determination of pymetrozine in soil, rice straw, paddy water and brown rice was developed. Pymetrozine residues were extracted from samples, cleaned up by solid phase extraction (SPE) and then determined by high-performance liquid chromatography electrospray ionization tandem mass spectrometry (LC–ESI–MS–MS). The average recovery was 81.2–88.1% from soil, 83.4–88.6% from rice straw, 87.3–94.1% from paddy water and 82.9–85.3% from brown rice. The relative standard deviation (RSD) was less than 15%. The limits of detection (LODs) of pymetrozine calculated as a sample concentration were 0.0003mgkg−1 (mg L−1) for soil and paddy water, 0.001mgkg−1 for brown rice and rice straw. The results of kinetics study of pymetrozine residue showed that pymetrozine degradation in water, soil, and rice straw coincided with C =0.194e−0.986t, C =0.044e−0.099t, and C =0.988e−0.780t, respectively; the half-lives were about 0.70d, 7.0d and 0.89d, respectively. The degradation rate of pymetrozine in water was the fastest, followed by rice straw. The highest final pymetrozine residues in brown rice were 0.01mgkg−1, which was lower than the EU’s upper limit of 0.02mgkg−1 in rice. Therefore, a dosage of 300–600ga.i.hm−2 was recommended, which could be considered as safe to human beings and animals. [ABSTRACT FROM AUTHOR]

Iron (Fe) deficiency is one of the most common micronutrient deficiencies limiting crop production globally, especially in arid regions because of decreased availability of iron in alkaline soils. Sweet potato [Ipomoea batatas (L.) Lam.] grows well in arid regions and is tolerant to Fe deficiency. Here, we report that the transcription of type I H + -pyrophosphatase (H + -PPase) gene IbVP1 in sweet potato plants was strongly induced by Fe deficiency and auxin in hydroponics, improving Fe acquisition via increased rhizosphere acidification and auxin regulation. When overexpressed, transgenic plants show higher pyrophosphate hydrolysis and plasma membrane H + -ATPase activity compared with the wild type, leading to increased rhizosphere acidification. The IbVP1-overexpressing plants showed better growth, including enlarged root systems, under Fe-sufficient or Fe-deficient conditions. Increased ferric precipitation and ferric chelate reductase activity in the roots of transgenic lines indicate improved iron uptake, which is also confirmed by increased Fe content and up-regulation of Fe uptake genes, e.g. FRO2, IRT1 and FIT. Carbohydrate metabolism is significantly affected in the transgenic lines, showing increased sugar and starch content associated with the increased expression of AGPase and SUT1 genes and the decrease in β-amylase gene expression. Improved antioxidant capacities were also detected in the transgenic plants, which showed reduced H 2 O 2 accumulation associated with up-regulated ROS-scavenging activity. Therefore, H + -PPase plays a key role in the response to Fe deficiency by sweet potato and effectively improves the Fe acquisition by overexpressing IbVP1 in crops cultivated in micronutrient-deficient soils., (© 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.)