Metabolomics and transcriptomics analyses provide new insights into the nutritional quality during the endosperm development of different ploidy rice

Autotetraploid rice is developed from diploid rice by doubling the chromosomes, leading to higher nutritional quality. Nevertheless, there is little information about the abundances of different metabolites and their changes during endosperm development in autotetraploid rice. In this research, two different kinds of rice, autotetraploid rice (AJNT-4x) and diploid rice (AJNT-2x), were subjected to experiments at various time points during endosperm development. A total of 422 differential metabolites, were identified by applying a widely used metabolomics technique based on LC-MS/MS. KEGG classification and enrichment analysis showed the differences in metabolites were primarily related to biosynthesis of secondary metabolites, microbial metabolism in diverse environments, biosynthesis of cofactors, and so on. Twenty common differential metabolites were found at three developmental stages of 10, 15 and 20 DAFs, which were considered the key metabolites. To identify the regulatory genes of metabolites, the experimental material was subjected to transcriptome sequencing. The DEGs were mainly enriched in starch and sucrose metabolism at 10 DAF, and in ribosome and biosynthesis of amino acids at 15 DAF, and in biosynthesis of secondary metabolites at 20 DAF. The numbers of enriched pathways and the DEGs gradually increased with endosperm development of rice. The related metabolic pathways of rice nutritional quality are cysteine and methionine metabolism, tryptophan metabolism, lysine biosynthesis and histidine metabolism, and so on. The expression level of the genes regulating lysine content was higher in AJNT-4x than in AJNT-2x. By applying CRISPR/Cas9 gene-editing technology, we identified two novel genes, OsLC4 and OsLC3, negatively regulated lysine content. These findings offer novel insight into dynamic metabolites and genes expression variations during endosperm development of different ploidy rice, which will aid in the creation of rice varieties with better grain nutritional quality

Relationship between the Composition of Flavonoids and Flower Colors Variation in Tropical Water Lily (Nymphaea) Cultivars

Water lily, the member of the Nymphaeaceae family, is the symbol of Buddhism and Brahmanism in India. Despite its limited researches on flower color variations and formation mechanism, water lily has background of blue flowers and displays an exceptionally wide diversity of flower colors from purple, red, blue to yellow, in nature. In this study, 34 flavonoids were identified among 35 tropical cultivars by high-performance liquid chromatography (HPLC) with photodiode array detection (DAD) and electrospray ionization mass spectrometry (ESI-MS). Among them, four anthocyanins: delphinidin 3-O-rhamnosyl-5-O-galactoside (Dp3Rh5Ga), delphinidin 3-O-(2″-O-galloyl-6″-O-oxalyl-rhamnoside) (Dp3galloyl-oxalylRh), delphinidin 3-O-(6″-O-acetyl-β-glucopyranoside) (Dp3acetylG) and cyanidin 3- O-(2″-O-galloyl-galactopyranoside)-5-O-rhamnoside (Cy3galloylGa5Rh), one chalcone: chalcononaringenin 2′-O-galactoside (Chal2′Ga) and twelve flavonols: myricetin 7-O-rhamnosyl-(1→2)-rhamnoside (My7RhRh), quercetin 7-O-galactosyl-(1→2)-rhamnoside (Qu7GaRh), quercetin 7-O-galactoside (Qu7Ga), kaempferol 7-O-galactosyl-(1→2)-rhamnoside (Km7GaRh), myricetin 3-O-galactoside (My3Ga), kaempferol 7-O-galloylgalactosyl-(1→2)-rhamnoside (Km7galloylGaRh), myricetin 3-O-galloylrhamnoside (My3galloylRh), kaempferol 3-O-galactoside (Km3Ga), isorhamnetin 7-O-galactoside (Is7Ga), isorhamnetin 7-O-xyloside (Is7Xy), kaempferol 3-O-(3″-acetylrhamnoside) (Km3-3″acetylRh) and quercetin 3-O-acetylgalactoside (Qu3acetylGa) were identified in the petals of tropic water lily for the first time. Meanwhile a multivariate analysis was used to explore the relationship between pigments and flower color. By comparing, the cultivars which were detected delphinidin 3-galactoside (Dp3Ga) presented amaranth, and detected delphinidin 3′-galactoside (Dp3′Ga) presented blue. However, the derivatives of delphinidin and cyanidin were more complicated in red group. No anthocyanins were detected within white and yellow group. At the same time a possible flavonoid biosynthesis pathway of tropical water lily was presumed putatively. These studies will help to elucidate the evolution mechanism on the formation of flower colors and provide theoretical basis for outcross breeding and developing health care products from this plant

Cluster synchronization for networks of generic linear systems and nonlinear oscillators via intermittent pinning control

This paper is concerned with applying intermittent pinning controllers to synchronization of interacting clusters of linearly coupled heterogeneous linear systems and nonlinear oscillators under general coupling topology. The cluster synchronization is analyzed via a unified approach to convergence analysis. The key idea of the work is based on the observation that the given cluster synchronization patterns can be realized if the underlying topology of each extended cluster has a directed spanning tree and an algebraic condition is satisfied. Then structural conditions are developed to ensure the related algebraic condition. Specifically, for linear systems, the algebraic condition can be guaranteed if the strength of the intra-cluster couplings are sufficiently strong and meanwhile the work time of the pinning controller in each period is sufficiently long; for nonlinear oscillators, the work time of the pinning controller can be arbitrarily short as long as the intra-cluster coupling strength for each cluster is sufficiently strong. Furthermore, both the lower bounds for such coupling strengths and length of the work time of the pinning controller in each period are explicitly specified

Perylene tetracarboxylic bisimide decorated g-C3N4 with enhanced photocatalytic activity

A water-soluble perylene bisimide derivative, N, N'-di(2-succinic acid)-perylene-3, 4, 9, 10-tetracarboxylic bisimide (PASP) was synthesized by using 3, 4, 9, 10-perylenetetracarboxylic dianhydride and L-aspartic acid as starting materials. The PASP were grafted onto graphitic carbon nitride (g-C3N4) via hydrothermal method to prepare PASP modified g-C3N4 hybrid photocatalyst (g-C3N4-PASP). The composition, structure, morphology and optical properties of the prepared g-C3N4-PASP samples were typically characterized by X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM), transmission electron microscopy(TEM), UV-Vis diffuse reflectance spectroscopy(UV-Vis DRS), and solid-state fluorescence spectroscopy. In addition, the photocatalytic activities of the prepared g-C3N4-PASP photocatalysts were evaluated by decomposition of methylene blue(MB) pollutant in water solution under visible light. The results reveal that PASP can be facilely linked to the g-C3N4 covalently via amide bond by hydrothermal treatment; compared to pristine g-C3N4, the g-C3N4-PASP possesses obviously higher specific surface area, dramatic red shifted absorption edge of 614 nm, and more efficient charge separation. Therefore, the visible light photo-catalytic degradation of MB pollution in water over the g-C3N4-PASP is notably improved. The g-C3N4-PASP could degrade 99.4% of MB dyes in 60 min under visible light irradiations (λ >420 nm), with a pseudo-first-order rate constant 2 times higher than that of pristine g-C3N4

A critical review on phase change material energy storage systems with cascaded configurations

© 2020 Elsevier Ltd This paper reviews cascaded or multiple phase change materials (PCMs) approach to provide a fundamental understanding of their thermal behaviors, the performance in terms of heat transfer uniformity, and the influence of input parameters and different geometrical containments on the performance of latent heat thermal energy storage (LHTES) systems. Furthermore, the performance enhancement of energy components through the implementation of cascaded techniques and cascaded arrangements of PCMs accompanied by other enhancement approaches is discussed. The influence of stage numbers affecting the performance of the cascaded LHTES unit is summarized and the range of recommended values for those parameters is provided. Our critical evaluation demonstrates that replacing single PCM by multiple PCMs shows the possibility of improving the performance of TES in terms of energy, exergy and entransy charging/discharging rate along with increased stored/retrieved energy and exergy efficiency. It is also shown that the cascaded LHTES systems opens the doors of opportunity for the seasonal energy sources and extracting the optimum amount of energy within the stipulated time through the proper arrangement of PCMs. Finally, the discussions are extended to the challenges of implementing the cascaded PCMs with some recommendations for future research in this direction

Renewable energy potential towards attainment of net-zero energy buildings status – A critical review

Global warming, climate change, and resource depletion have forced us to reconsider energy usage and efficiencies over the last few decades. Residential and commercial buildings are both large energy consumers, so improving energy and material usage efficiency in this sector is a common research topic. According to a recent study, the Building Sector (BS) accounts for 40% of greenhouse gas emissions. The primary objective of this paper is to examine and assess the potential of Renewable Energy Systems (RES) and their combinations for enhancing energy efficiency in the BS. Specifically, the focus will be on converting low energy-efficient buildings into highly efficient ones. The potential of the RES and their combinations for the BS is evaluated based on payback durations, energy generation, and reduction of CO2 emissions. The optimization flow charts for the RES, feasibility studies, commercialization road maps of energy storage systems and the necessity of control mechanisms for enhancing RES efficiency were discussed. Additionally, the technology drawbacks are discussed, along with various innovative techniques recommended to direct future study in this area. Finally, this article assists the audience clear idea in the selection of the right combination of potential RES based on different conditions to achieve deep decarbonization in BSs