Gas exchange, photosystem II photochemistry, and the antioxidant system of longan plant (Dimocarpus longan Lour.) leaves in response to lead (Pb) stress

Abstract Longan is one of the most important subtropical fruit trees and a famous special product in south China. Increased fruit demand brings longan cultivation to Pb-affected regions. Seedlings of longan (cv. Wulongling) in pots with sands were irrigated daily for 30 d with a freshly prepared nutrient solution containing different concentrations of Pb(NO 3 ) 2 (0, 100 , 200 , 400 , 600 , 800 and 1000 mg L -1 ) to determine physiological and biochemical responses of longan seedlings to various levels of lead (Pb). The results indicated that Pb stress substantially inhibited the growth of longan plants and markedly declined in their dry biomass. However, when the plants were grown at 100 mg L -1 Pb, the growth and dry biomass of the plants showed no significant difference from control. In addition, the chlorophyll a fluorescence and gas exchange parameters were correlated with the growth and yield response. Pb treatments increased the minimum fluorescence (Fo) and caused a decrease in maximum fluorescence (Fm), variable fluorescence (Fv), the maximum quantum efficiency of PSII photochemistry (Fv/Fm), trapped energy flux per cross section (CS) at t=0 (TRo/CSo), electron transport flux per CS at t=0 (ETo/CSo), dissipated energy flux per CS at t=0(DIo/CSo), and the amount of active PSII reaction centers (RCs) per CS at t = 0 (RC/CSo). Furthermore, Pb stress led to decreases in the protein contents, the activity of peroxidase (POD, EC 1.11.1.7) and the accumulation of proline and malondialdehyde (MDA), and enhanced superoxide dismutase activity (SOD, EC 1.15.1.1), whereas catalase (CAT, EC 1.11.1.6) and ascorbate peroxidase (APX,EC 1.11.1.11) were enhanced at low Pb levels and decreased under high Pb stress. Nonetheless, these changes were closely related to the severity of the Pb stress

Danggui Sini Decoction (herbal medicine) for the treatment of primary dysmenorrhoea: a systematic review and meta-analysis

Danggui Sini Decoction (DSD), a traditional herbal prescription, has been commonly used in the treatment of primary dysmenorrhoea (PD). We investigated the current evidence of randomised controlled trials (RCTs) and performed a systematic review to evaluate the efficacy of DSD in the treatment of PD. We registered the protocol for this systemic review in PROSPERO with the registration number CRD 42017074062 on August 10, 2017. Nine databases were searched from inception to August 2019. Eleven RCTs with 1005 patients were included. DSD was shown to have more favourable effects on the clinical effective rate than western medicine, which support the clinical use of DSD in the treatment of PD. However, considering the high risk of bias in the included studies, more well-designed RCTs are needed to further evaluate the efficacy of DSD in the treatment of PD

Analysis of genetic diversity and relationships between late-mature peach (Prunus persica L.) varieties assessed with ISSR and SRAP markers

Molecular characterization of 39 late-mature peach (Prunus persica L.) accessions was carried out using ISSR (inter simple sequence repeats) and SRAP (sequence-related amplified polymorphism) markers to assess the value and magnitude of genetic divergence. The ISSR primers revealed 70.09% polymorphism and the SRAP marker generated 73.33% polymorphism. Pooled ISSR and SRAP, along with UPGMA clustering based on similarity coefficients, were estimated to assess the efficiency of the marker system in peaches. Similarity coefficients between accessions regarding the ISSR and SRAP markers ranged from 0.65 to 0.89, indicating a broad genetic peach base. A maximum similarity coefficient of 0.89 was observed between C12 'Weiduanmihong' (Fujian Yikangyuan Farm Co., Ltd., 26.58° N, 118.75° E) and C32 'Weiduanmihong' (WeiduanVillage, 26.58° N, 118.75° E), and a minimum of 0.65 was observed in C6 'Huangjinmitao 5' (Gutian Natural Pantaoyuan Family Farm, 26.58° N, 118.75° E) and the rest of the genotypes. The present study found that a high level of polymorphism indicated their applicability in framing more extensive studies to develop superior progeny, conduct molecular breeding, investigate genetic population diversity, make comparative maps, select parents, etc., in various peach crop improvement programs

Rapid Determination of Nitrate Nitrogen Isotope in Water Using Fourier Transform Infrared Attenuated Total Reflectance Spectroscopy (FTIR-ATR) Coupled with Deconvolution Algorithm

Nitrate is a prominent pollutant in water bodies around the world. The isotopes in nitrate provide an effective approach to trace the sources and transformations of nitrate in water bodies. However, determination of isotopic composition by conventional analytical techniques is time-consuming, laborious, and expensive, and alternative methods are urgently needed. In this study, the rapid determination of 15NO3− in water bodies using Fourier transform infrared attenuated total reflectance spectroscopy (FTIR-ATR) coupled with a deconvolution algorithm and a partial least squares regression (PLSR) model was explored. The results indicated that the characteristic peaks of 14NO3−/15NO3− mixtures with varied 14N/15N ratios were observed, and the proportion of 15NO3− was negatively correlated with the wavenumber of absorption peaks. The PLSR models for nitrate prediction of 14NO3−/15NO3− mixtures with different proportions were established based on deconvoluted spectra, which exhibited good performance with the ratio of prediction to deviation (RPD) values of more than 2.0 and the correlation coefficients (R2) of more than 0.84. Overall, the spectra pretreatment by the deconvolution algorithm dramatically improved the prediction models. Therefore, FTIR-ATR combined with deconvolution and PLSR provided a rapid, simple, and affordable method for determination of 15NO3− content in water bodies, which would facilitate and enhance the study of nitrate sources and water environment quality management

Effects of Exogenous Substances Treatment on Fruit Quality and Pericarp Anthocyanin Metabolism of Peach

In this study, the two peach cultivars ‘Baifeng’ and ‘Weiduanmihong’ were used as experimental materials, and their fruits were sprayed with different concentrations of L-glutamic acid, brassinolide, and sucrose to study the effects of these three exogenous substances on fruit quality and anthocyanin metabolism of peaches. The results showed that the appearance quality (average single fruit weight, fruit firmness, and peel color difference), nutritional quality (soluble solids, soluble sugar, titratable acid, anthocyanins, total phenols, flavonoids, etc.), peel anthocyanin-related enzyme activity, and related gene expression of ‘Baifeng’ and ‘Weiduanmihong’ peaches treated with three different exogenous substances were different from those of the control. Higher-concentration treatments could significantly improve the appearance of peach fruit, the nutritional quality of peach fruit and the activity of anthocyanin-related enzymes in peel, as well as promote the expression of related genes. Treatment with 400 mg/L L-glutamic acid significantly promoted the average fruit weight of ‘Baifeng’ peaches. Treatment with 800 mg/L L-glutamic acid significantly promoted the increase in PAL enzyme activity and the expression of PpPAL and PpF3H in the two peach varieties and significantly promoted the expression of anthocyanin metabolism genes PpF3′H and PpGST1 in ‘Baifeng’ peach peel and anthocyanin metabolism gene PpUFGT in ‘Weiduanmihong’ peach peel. Treatment with 34 mg/L sucrose significantly increased the fruit firmness of ‘Baifeng’ peaches and the soluble sugar content of ‘Weiduanmihong’ peaches. Treatment with 51 mg/L sucrose significantly promoted the increase in flavonoid content and PpUFGT expression in ‘Baifeng’ peach fruit and significantly promoted the expression of anthocyanin metabolism genes PpDFR and PpANS in ‘Weiduanmihong’ peach peel. Treatment with 0.6 mg/L brassinolide significantly promoted the increase in soluble solids (TTS), soluble sugar, anthocyanin, total phenol content, PAL enzyme activity, UFGT enzyme activity, and the expression of anthocyanin metabolism genes PpDFR and PpMYB10.1 in ‘Baifeng’ peach fruit, and it significantly increased the average single fruit weight, fruit hardness, anthocyanin content, and UFGT enzyme activity of ‘Weiduanmihong’ peach fruit and promoted the expression of anthocyanin metabolism genes PpF3H and PpGST1 in ‘Weiduanmihong’ peach peel. The comprehensive effect of 0.6 mg/L brassinolide treatment on improving peach fruit quality and increasing anthocyanin content produces the best results and could be popularized in production practices

Absence of RstA results in delayed initiation of DNA replication in Escherichia coli.

RstB/RstA is an uncharacterized Escherichia coli two-component system, the regulatory effects of which on the E. coli cell cycle remain unclear. We found that the doubling time and average number of replication origins per cell in an ΔrstB mutant were the same as the wild-type, and the average number of replication origins in an ΔrstA mutant was 18.2% lower than in wild-type cells. The doubling times were 34 min, 35 min, and 40 min for the wild-type, ΔrstB, and ΔrstA strains, respectively. Ectopic expression of RstA from plasmid pACYC-rstA partly reversed the ΔrstA mutant phenotypes. The amount of initiator protein DnaA per cell was reduced by 40% in the ΔrstA mutant compared with the wild-type, but the concentration of DnaA did not change as the total amount of cellular protein was also reduced in these cells. Deletion or overproduction of RstA does not change the temperature sensitivity of dnaA46, dnaB252 and dnaC2. The expression of hupA was decreased by 0.53-fold in ΔrstA. RstA interacted with Topoisomerase I weakly in vivo and increased its activity of relaxing the negative supercoiled plasmid. Our data suggest that deletion of RstA leads to delayed initiation of DNA replication, and RstA may affect initiation of replication by controlling expression of dnaA or hupA. Furthermore, the delayed initiation may by caused by the decreased activity of topoisomerase I in RstA mutant

Neural Stem Cell-Conditioned Medium Ameliorated Cerebral Ischemia-Reperfusion Injury in Rats

Introduction. Our previous study suggested that NSC-CM (neural stem cell-conditioned medium) inhibited cell apoptosis in vitro. In addition, many studies have shown that neurotrophic factors and microparticles secreted into a conditioned medium by NSCs had neuroprotective effects. Thus, we hypothesized that NSC-CM had the capacity of protecting against cerebral I/R injury. Methods. Adult male Sprague-Dawley rats receiving middle cerebral artery occlusion surgery as an animal model of cerebral I/R injury were randomly assigned to two groups: the control group and NSC-CM-treated group. 1.5 ml NSC-CM or PBS (phosphate buffer saline) was administrated slowly by tail vein at 3 h, 24 h, and 48 h after ischemia onset. Results. NSC-CM significantly ameliorated neurological defects and reduced cerebral infarct volume, accompanied by preserved mitochondrial ultrastructure. In addition, we also found that NSC-CM significantly inhibited cell apoptosis in the ischemic hemisphere via improving the expression of Bcl-2 (B-cell lymphoma-2). Conclusion. NSC-CM might be an alternative and effective therapeutic intervention for ischemic stroke

Big data-enabled multiscale serviceability analysis for aging bridges☆

This work is dedicated to constructing a multi-scale structural health monitoring system to monitor and evaluate the serviceability of bridges based on the Hadoop Ecosystem (MS-SHM-Hadoop). By taking the advantages of the fault-tolerant distributed file system called the Hadoop Distributed File System (HDFS) and high-performance parallel data processing engine called MapReduce programming paradigm, MS-SHM-Hadoop features include high scalability and robustness in data ingestion, fusion, processing, retrieval, and analytics. MS-SHM-Hadoop is a multi-scale reliability analysis framework, which ranges from nationwide bridge-surveys, global structural integrity analysis, and structural component reliability analysis. This Nationwide bridge survey uses deep-learning techniques to evaluate the bridge serviceability according to real-time sensory data or archived bridge-related data such as traffic status, weather conditions and bridge structural configuration. The global structural integrity analysis of a targeted bridge is made by processing and analyzing the measured vibration signals incurred by external loads such as wind and traffic flow. Component-wise reliability analysis is also enabled by the deep learning technique, where the input data is derived from the measured structural load effects, hyper-spectral images, and moisture measurement of the structural components. As one of its major contributions, this work employs a Bayesian network to formulate the integral serviceability of a bridge according to its components serviceability and inter-component correlations. Here the inter-component correlations are jointly specified using a statistics-oriented machine learning method (e.g., association rule learning) or structural mechanics modeling and simulation

Changes in Fruit Quality Phytochemicals of Late-Mature Peach ‘Yonglian No.1’ during Storage

In this study, the changes in quality parameters and sensory-influencing parameters from the peel, red flesh, and white flesh of ‘Yonglian No.1’ peach fruits were analyzed during cold storage. The results indicated that the contents of total soluble solids (TSS), soluble sugar, organic acid, vitamin C, total anthocyanin, phenol, and flavonoids, as well as the good fruit rate varied depending on the storage stages and storage treatments. The peach fruits in MAP stored for 50 days had favorable exterior qualities, a good fruit rate of 100%, and a higher content of total soluble solids (TSS) at 12.6%. MAP was significantly effective at maintaining fruit firmness, the content of TSS, soluble sugar, organic acid, vitamin C, total anthocyanin, phenol, and flavonoids. Among the derivatives of anthocyanin, both cyanidin and pelargonidin were found in the peel, with a content of 33.45 mg/kg FW and 1.82 mg/kg FW, respectively. However, cyanidin was detected in the flesh with a content of 40.42 mg/kg FW. In the present work, the differences regarding phytochemical profiles and physical properties were mainly correlated with the storage stages and storage treatments of peach fruit. ‘Yonglian No.1’ had higher levels of health-promoting compounds during storage and maintained favorable quality

Comparison of physico-chemical characteristics of myrtle at different ripening stages

The fruits of myrtle at different stages of development, namely green (G), colour break (C) and mature (M), were used to investigate the changes of fruit quality and anthocyanin composition during its development. Five anthocyanin components, such as delphinidin (Dp), cyanidin (Cy), pelargonidin (Pg), peonidin (Pn) and malvidin (Mv), were detected. Among them, the content of Dp glucoside was the highest (2.12 μg · g−1) and the content of Pn glucoside was the lowest (0.17 μg · g−1) at the green stage. The content of Cy glucoside was the highest (120.94 and 1,200.03 μg · g−1), and the content of Mv glucoside was the lowest (19.50 and 62.72 μg · g−1) at the colour break and mature stages. The single fruit weight, vertical diameter and transverse diameter at the mature stage were significantly higher than those at the colour break and the green stages by 0.87 g, 1.27 mm, 1.53 mm and 1.54 g, 3.4 mm, 3.55 mm, respectively. Fruit quality, the contents of soluble sugar and carotenoids, gradually increased with the development of fruit; and the contents were the highest at the mature stage (17.68% and 16.90 μg · L−1). The contents of titratable acidity, total phenol, flavonoids, chlorophyll a and total chlorophyll gradually decreased with the development of fruit, the content was the lowest at the mature stage (2.71 mmol · 100 g−1, 9.29 μg · g−1, 0.1%, 0.37 μg · L−1, 0.9 μg · L−1) and the content was the highest at the green stage (5.25 mmol · 100 g−1, 21.07 μg · g−1, 0.17%, 8.86 μg · L−1, 15.47 μg · L−1). The difference between the green period and the colour break period was significant