Analysis of changes in the Panax notoginseng glycerolipidome in response to long-term chilling and heat

Long-term moderately high or low temperatures can damage economically important plants.In the present study,we treated Panax notoginseng,an important traditional Chinese medicine,with temperatures of 10,20,and 30℃for 30 days.We then investigated P.notoginseng glycerolipidome responses to these moderate temperature stresses using an ESI/MS-MS-based lipidomic approach.Both long-term chilling(LTC,10℃)and long-term heat(LTH,30℃)decreased photo pigment levels and photosynthetic rate.LTH-induced degradation of photo pigments and glycerolipids may further cause the decline of photosynthesis and thereafter the senescence of leaves.LTC-induced photosynthesis decline is attributed to the degradation of photo synthetic pigments rather than the degradation of chloroplastidic lipids.P.notoginseng has an especially high level of lysophosphatidylglycerol,which may indicate that either P.notoginseng phospholipase A acts in a special manner on phosphatidylglycerol(PG),or that phospholipase B acts.The ratio of sulfoquinovosyldiacylglycerol(SQDG)to PG increased significantly after LTC treatment,which may indicate that SQDG partially substitutes for PG.After LTC treatment,the increase in the degree of unsaturation of plastidic lipids was less than that of extraplastidic lipids,and the increase in the unsaturation of PG was the largest among the ten lipid classes tested.These results indicate that increasing the level of unsaturated PG may play a special role in maintaining the function and stability of P.notoginseng photosystems after LTC treatment.

Impacts of CO2 elevation on the physiology and seed quality of soybean

Understanding the responses of crops to elevated atmospheric carbon dioxide concentrations(E[CO2])is very important in terms of global food supplies.The present study investigates the effects of CO2 enrichment(to 800μmol mol^-1)on the physiology of soybean plants and the nutritional value of their seeds under growth chamber conditions.The photosynthesis of soybean was significantly promoted by E[CO2]at all growth stages,but leaf area and specific leaf weight were not affected.The levels of mineral elements in the leaves decreased under EICO2J.The soil properties after soybean cultivation under E[CO2]were not affected,except for a decrease in available potassium.Moreover,the levels of soluble sugars in the seeds were not affected by E[CO2].but the levels of natural antioxidants decreased.In addition,the level of oleic acid decreased under E[CO2].However,levels of fatty acid peroxidation and saturation were maintained.In conclusion.E[CO2] appears to have positive effects on the growth of cultivated soybean plants,but its influence on the nutritional values of soybean seeds is complex.Copyright?2019 Kunming Institute of Botany.Chinese Academy of Sciences.

Phospholipase D antagonist 1-butanol inhibited the mobilization of triacylglycerol during seed germination in Arabidopsis

Storage oil breakdown plays an important role in the life cycle of many plants by providing the carbon skeletons that support seedling growth immediately following germination. 1-Butanol, a specific inhibitor of phospholipase D(PLD)-dependent production of the signalling molecule phosphatidic acid(PA), inhibited Arabidopsis seed germination. N-Acylethanolamines(NAEs), which have been shown to inhibits PLDa1 activity, have no effect on seed germination. However, mobilization profile of triacylglycerols(TAG) that induced by each compound has not been reported. To gain deeper insights into the mode of mobilization of TAG during NAE 12:0 or 1-butanol treatment, we conducted a detailed comparative analysis of the effect of NAE 12:0, DMSO, 1-butanol and tert-butanol on Arabidopsis seed germination and fatty acid composition, tert-butanol and DMSO served as the corresponding controls treatment respectively. Our data show that 1-butanol, but not the inactive tert-butanol isomer, inhibited Arabidopsis seed germination, which is accompanied by a with retardation of the mobilization of triacylglycerols(TAG). In contrast, NAE 12:0 did not affect mobilization of TAG, nor did it significantly delay seed germination as monitored by radicle and cotyledon emergence. 1-Butanol induced RNA degradation in seeds and seedlings. We speculate that the large-scale degradation of RNA under the induction of 1-butanol may lead to abnormal gene expression in genes necessary for seed germination, including the genes needed for the mobilization of oil bodies, and thus cause a delay of seed germination. To the best of our knowledge, we report for the first time that 1-butanol delays the mobilization of TAG.

Submergence induced changes of molecular species in membrane lipids in Arabidopsis thaliana

The composition of membrane lipids is sensitive to environmental stresses.Submergence is a type of stress often encountered by plants.However,how the molecular species of membrane lipids respond to submergence has not yet been characterised.In this study,we used a lipidomic approach to profile the molecular species of membrane lipids in whole plants of Arabidopsis thaliana that were completely submerged for three days.The plants survived one day of submergence,after which,we found that the total membrane lipids were only subtly decreased,showing significant decreases of monogalactosyldiacylglycerol(MGDG)and phosphatidylcholine(PC)and an increase of phosphatidic acid(PA);however,the basic lipid composition was retained.In contrast,three days of submergence caused plants to die,and the membranes deteriorated via the rapid loss of 96% of lipid content together with a 229% increase in PA.The turnover of molecular species from PG and MGDG to PA indicated that submergenceinduced lipid changes occurred through PA-mediated degradation.In addition,molecular species of extraplastidic PG degraded sooner than plastidic ones,lyso-phospholipids exhibited various patterns of change,and the double-bond index(DBI)remained unchanged until membrane deterioration.Our results revealed the unique changes of membrane lipids upon submergence and suggested that the major cause of the massive lipid degradation could be anoxia.

A Parallel Search System for Dynamic Multi-Objective Traveling Salesman Problem

This paper introduces a parallel search system for dynamic multi-objective traveling salesman problem. We design a multi-objective TSP in a stochastic dynamic environment. This dynamic setting of the problem is very useful for routing in ad-hoc networks. The proposed search system first uses parallel processors to identify the extreme solutions of the search space for each ofk objectives individually at the same time. These solutions are merged into the so-called hit-frequency matrix E. The solutions in E are then searched by parallel processors and evaluated for dominance relationship. The search system is implemented in two different ways master-worker architecture and pipeline architecture.

Characterisation of manganese toxicity tolerance in Arabis paniculata

Manganese(Mn)contamination limits the production and quality of crops,and affects human health by disrupting the food chain.Arabis paniculata is a pioneer species of Brassicaceae found in mining areas,and has the ability to accumulate heavy metals.However,little is known about the genetic mechanisms of Mn tolerance in A.paniculata.In this study,we found that Mn tolerance and ability to accumulate Mn were higher in A.paniculata than in Arabidopsis thaliana.The mechanisms underlying the response and recovery of A.paniculata to Mn toxicity were further investigated using transcriptome analysis.A total of 69,862,281 base pair clean reads were assembled into 61,627 high-quality unigenes,of which 41,591(67.5%)and 39,297(63.8%)were aligned in the Kyoto Encyclopedia of Genes and Genomes(KEGG)and Gene Ontology(GO),respectively.In response to Mn toxicity,genes were expressed in twelve distinct patterns,which can be divided into four general categories:initial,stable,dose-dependent,and lineage.Genes that were differentially expressed during Mn response and recovery belong to several dominant KEGG pathways.An early response to Mn toxicity in A.paniculata includes the upregulation of genes involved in glutathione metabolism.ATP-binding cassette(ABC)transporter proteins were up-regulated during the entire response phase,and genes involved in glycerophospholipid metabolism were upregulated during the late phase of the Mn response.Genes in the phenylpropanoid pathway were differentially expressed in the repair process after Mn treatment.These findings reveal ideal material and genetic resources for phytoremediation in Mn-contaminated areas and highlight new knowledge and theoretical perspectives on the mechanisms of Mn tolerance.

Flavonoid scutellarin positively regulates root length through NUTCRACKER

Exploring approaches to regulate meristem is of special importance and broad interest.In this study,we found that the flavonoid scutellarin,which has a 6-hydroxyl and a 7-glucoside,increased root length through the transcription factor NUTCRACKER(NUC).This root lengthening disappeared in NUCknockout and reappeared in NUC-rescue plants.Scutellarin induced NUC expression and promoted the division of cortex/endodermal initials.In contrast,naringenin,which has same chemical backbone but without 6-hydroxyl and with 7-hydroxyl group,showed the opposite or no effects.Our results demonstrate that scutellarin promotes root length through NUC-mediated regulatory pathways and reveal that flavonoids with and without the 6-hydroxyl and 7-glucoside have positive and negative effects on meristem size,respectively。

One Novel Zn(Ⅱ)Nitro-containing Metal Organic Framework for Dye-Adsorption and Photo Degradation

A novel metal-organic framework[Zn0.5(L1)(4,4'-Bpy)0.5],(HU21,HU for Hohai University,L1=4-hydroxy-3-nitrobenzoic acid,4,4'-bipyridine=4,4'-Bpy),has been isolated through hydro-thermal reaction.Single-crystal X-ray diffraction reveals the compound features a 1D fishbone-like chain.A fast adsorption rate of methylene blue with HU21 was observed in the dark,but under irritation the degradation rate of the dye was obviously increased.The degradation of methylene blue dye reached 248 mg/g under light irritation,and the photocatalytic activity reached 96.1%.

One dimensional terpyridine-based metal organic framework for stable supercapacitor

In summary,a novel structure of MOF based on 1,4-di([2,2':6',2''terpyridin]-4'-yl)benzene and 1,4-naphthalenedicarboxylic acid has been constructed through hydrothermal reaction.The Ni-MOF displays one dimensional zigzag chain,which connect each other by hydrogen bonding to form three dimensional supramolecule with large channels.The conjugated systems of the terpyridin and benzene ligands enhance the chain rigidity,accelerate the electron transport.The massive channels provides electrolyte rapid transfer.By the structural feature aforementioned,the Ni-MOF demonstrates stable electrochemical performance as suprocapacitor.

Sparkling hot spots in perovskite solar cells under reverse bias

Perovskite solar cells(PSCs)are attracting much attention and are on the way to commercialization.However,some modules are subject to reverse bias in actual fields,so it is meaningful to investigate the reverse-bias behav-ior of PSCs.Herein,an in-situ temperature and current measurement technique was developed.Intriguingly,some hot spots were observed and then quickly disappeared in the reverse biased PSCs,along with the simultaneous increase in the current and local temperature.Also,the potential mechanism has been revealed and analyzed.An abnormal bulge in the perovskite film was found at the hot spot.Accordingly,the appearance and disappearance of hot spots were perfectly explained by band bending and tunneling current caused by ion accumulation.Addi-tionally,statistical analysis suggested that sparkling hot spots were related to reverse voltage and efficiencies of PSCs.The research provides a great significance for the study of PSCs under reverse bias.

Graphdiyne oxide substrate-enhanced peroxidase-mimicking performance of Ru nanoparticles with physiological pH preference

Modulating electronic structure of metal nanoparticles via metal–support interaction has attracted intense interest in the field of catalytic science.However,the roles of supporting substrates in regulating catalytic properties of nanozymes remain elusive.In this study,we find that the use of graphdiyne oxide(GDYO)as the substrate for self-terminating growth of Ru nanoparticles(Ru@GDYO)endows the peroxidase-like activity of Ru nanoparticles with intrinsic physiological pH preference and natural horseradish peroxidase(HRP)comparable performance.Ru nanoparticles electrolessly deposited onto GDYO possess a partially oxidized electronic structure owing to limited charge transfer between Ru and GDYO,contributing to the intrinsic physiological pH preference of the peroxidase-mimicking nanozyme.More importantly,the substrate GDYO plays an influential factor in enhancing catalytic activity,that is,the activity of Ru@GDYO is much higher than that of Ru nanoparticles deposited on other carbon substrates including graphene oxides and graphdiyne.To demonstrate the application of Ru@GDYO nanozyme in neutral solutions,we employ Ru@GDYO with nicotinamide adenine dinucleotide(NAD+)-dependent dehydrogenases in physiological conditions to realize a sustainable cascade reaction by means of forming continuous NAD^(+)/dihydronicotiamide adenine dinucleotide(NADH)recycling.Our finding represents a promising perspective on designing high-performance peroxidase-mimicking nanozymes with broader applicability,raising fundamental understanding of structure–activity relationship,and investigating new applications of nanozymes in biological systems.

Molecular cloning,tissue distribution and the expression of cystine/glutamate exchanger(xCT,SLC7A11) in different tissues during development in broiler chickens

The cystine/glutamate exchanger(xCT,SLC7 A11)is a component of the system X_c amino-acid antiporter that is able to export glutamate and import cysteine into cells.The xCT amino acid exchanger has received a lot of attention,due to the fact that cysteine is an essential substrate for the synthesis of glutathione(GSH),an endogenous antioxidant in cells.The objective of this research was to clone the full-length cDNA of chicken xCT,and to investigate the gene expression of xCT in different tissues,including intestinal segments of broiler chickens during development.The full-length cDNA of chicken xCT(2,703 bp)was obtained from the jejunum by reverse transcription-PCR and sequenced.Homology tests showed that chicken xCT had 80.4%,80.2%,and 71.2%homology at the nucleotide level with humans,cattle,and rats,respectively.Likewise,amino acid sequence analysis showed that chicken xCT protein is 86.4%,79.3%,and 75.6%homologous with humans,cattle,and rats,respectively.Additionally,phylogenetic analysis indicated that chicken xCT genes share a closer genetic relationship with humans and cattle,than with rats.The chicken xCT protein has 12 transmembrane helixes,6 extracellular loops,and 5 intracellular loops.The mRNA of xCT was detected in all tissues,including intestinal segments,in which the mRNA expression of xCT was significantly higher(P<0.05)within the colon,compared to the jejunum and ileum.During development,a linear pattern of changes regarding the levels of the xCT mRNA was found,indicating that there was an abundance of xCT within the duodenum(P<0.05).Furthermore,there were changes of the xCT mRNA abundance in the colon during development,which displayed linear and cubic patterns(P<0.05).These results indicated that xCT is widely expressed both in intestinal segments,as well as other organs that are not associated with nutrient absorption.Further investigation is needed to characterize the functional relevance of xCT activity in oxidative stress and inflammation in the small intestine of broiler chickens.

Aging process design based on the morphological evolution ofγprecipitates in a 4th generation nickel-based single crystal superalloy

In order to meet the design requirements of the aging treatment process of a 4th generation nickel-based single crystal superalloy(Ni-SX)developed independently,the effects of aging temperatures and aging times on the precipitation and morphological evolution ofγprecipitates are studied.The morphological evolution behavior ofγprecipitates during the aging process is summarized subsequently and the coarsening behavior ofγprecipitates is discussed by comparing with the Lifshitz-Slyozov-Wagner model(LSW)and the trans-interface diffusion-controlled model(TIDC).It is demonstrated that primary aging temperature and secondary aging time dominate the size and squareness ofγprecipitates respectively,a narrow primary aging temperature range and a suitable secondary aging time are allowed to obtain the optimized morphology ofγprecipitates.The optimal aging process of the Ni-SX investigated in the present work is obtained for 1100-1120°C/4 h and 870°C/16 h,confirmed by the corresponding creep tests.The coarsening growth ofγprecipitates in short-term aging also conforms to the LSW model well.Besides,the aging process design rules of various Ni-SXs of different generations are also summarized.

Phase-pure two-dimensional Fe_(X)GeTe_(2) magnets with near-room-temperature Tc

Two-dimensional(2D)ferromagnets with out-of-plane(OOP)magnetic anisotropy are potential candidates for realizing the next-generation memory devices with ultra-low power consumption and high storage density.However,a scalable approach to synthesize 2D magnets with OOP anisotropy directly on the complimentary metal-oxide semiconductor(CMOS)compatible substrates has not yet been mainly explored,which hinders the practical application of 2D magnets.This work demonstrates a cascaded space confined chemical vapor deposition(CS-CVD)technique to synthesize 2D FexGeTe_(2) ferromagnets.The weight fraction of iron(Fe)in the precursor controls the phase purity of the as-grown FexGeTe2.As a result,high-quality Fe_(3)GeTe_(2) and Fe_(5)GeTe_(2) flakes have been grown selectively using the CS-CVD technique.Curie temperature(Tc)of the as-grown FexGeTe2 can be up to-280 K,nearly room temperature.The thickness and temperature-dependent magnetic studies on the Fe_(5)GeTe_(2) reveal a 2D Ising to 3D XY behavior.Also,Terahertz spectroscopy experiments on Fe_(5)GeTe_(2) display the highest conductivity among other FexGeTe_(2) 2D magnets.The results of this work indicate a scalable pathway for the direct growth and integration of 2D ternary magnets on CMOS-based substrates to develop spintronic memory devices.

Fluidic memristor:Bringing chemistry to neuromorphic devices

Neuromorphic devices,devices with resistance switch dynamic emulating the behavior of neurons,are experiencing a surge in development due to the demand for artificial intelligence and therapeutic devices such as neuroprosthetics.1 Toward reproducing the behaviors of neurons with artificial devices,neuromorphic devices based on two-terminalmemristors(devices with a single-valued relationship between charge Q and magnetic flux 4,i.e.,d4=MdQ)with various mechanisms(e.g.,redox,phase change,magnetic tunnelling,and ferroelectricity)have been developed for various applications,like in-memory computing or intelligent sensing.2 However,the performances and functions of these devices still lag behind those of real neurons.For example,biological neurons are strongly responsible for chemical changes in electrolyte solutions induced by transmitters and regulators,while most neuromorphic devices only show responses to the stimulations of electrical signals.Detecting and responding to these chemical signals could not only improve the performances of neuromorphic computing but also offer brand-new functions in brain-computer interfaces.However,the fabrication of neuromorphic devices responsible for chemical information remains a great problem since the founding of the memristor.