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Salinity stress is a serious limitation to tomato growth and development. The aim of this study was to investigate the effects of Sly-miR164a on tomato growth and fruit nutritional quality under salt stress. The results showed that the root length, fresh weight, plant height, stem diameter and ABA content of miR164a#STTM (knockdown of Sly-miR164a) lines were higher than those of WT and miR164a#OE (overexpression of Sly-miR164a) lines under salt stress. Compared with WT, miR164a#STTM tomato lines exhibited lower ROS accumulation under salt stress. In addition, the fruits of miR164a#STTM tomato lines had higher soluble solids, lycopene, ascorbic acid (ASA) and carotenoid content compared with WT. The study indicated that tomato plants were more sensitive to salt when Sly-miR164a was overexpressed, while knockdown of Sly-miR164a enhanced plant salt tolerance and improved fruit nutritional value.
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Solanum lycopersicum , Tolerância ao Sal , Plantas Geneticamente Modificadas/metabolismo , Frutas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de PlantasRESUMO
Time-periodic light field has emerged as a control knob for manipulating quantum states in solid-state materials1-3, cold atoms4 and photonic systems5 through hybridization with photon-dressed Floquet states6 in the strong-coupling limit, dubbed Floquet engineering. Such interaction leads to tailored properties of quantum materials7-11, for example, modifications of the topological properties of Dirac materials12,13 and modulation of the optical response14-16. Despite extensive research interests over the past decade3,8,17-20, there is no experimental evidence of momentum-resolved Floquet band engineering of semiconductors, which is a crucial step to extend Floquet engineering to a wide range of solid-state materials. Here, on the basis of time and angle-resolved photoemission spectroscopy measurements, we report experimental signatures of Floquet band engineering in a model semiconductor, black phosphorus. On near-resonance pumping at a photon energy of 340-440 meV, a strong band renormalization is observed near the band edges. In particular, light-induced dynamical gap opening is resolved at the resonance points, which emerges simultaneously with the Floquet sidebands. Moreover, the band renormalization shows a strong selection rule favouring pump polarization along the armchair direction, suggesting pseudospin selectivity for the Floquetband engineering as enforced by the lattice symmetry. Our work demonstrates pseudospin-selective Floquet band engineering in black phosphorus and provides important guiding principles for Floquet engineering of semiconductors.
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BACKGROUND: The incidence of cardiovascular events remains not unusual in patients following percutaneous coronary intervention (PCI) due to acute coronary syndrome (ACS). Chinese patent medicine (CPM) therapy based on syndrome differentiation in addition to conventional medicine (CM) had been expected to further reduce the risk of cardiovascular events. PURPOSE: To assess the effectiveness and safety of CPM based on syndrome differentiation in patients following PCI due to ACS. STUDY DESIGN: Nationwide prospective cohort study. METHODS: CPM study was conducted in 40 centers in mainland China. Patients following PCI due to ACS entered to syndrome differentiation-based CPM (SDCPM) or CM group according to whether they received CPM or not. The CPM comprised Guanxin Danshen dripping pills, Qishen Yiqi dripping pills, or Danlou tablets, and was used correspondingly with the syndrome differentiation of traditional Chinese medicine. The follow-up time was 36 months. The primary endpoint was composed of cardiac death, non-fatal myocardial infarction and urgent revascularization. The secondary endpoint included rehospitalization due to ACS, heart failure, stroke, other thrombotic events. Seattle Angina Questionnaire (SAQ) was used to evaluate quality of life. RESULTS: Between February 2012 and December 2018, ascertainment of the primary endpoint was completed in 2,724 patients of follow-up. 1,380 patients were in SDCPM group. At a median follow-up of 541 (interquartile range 513 - 564) days, the primary endpoint occurred in 126 (8.61%) patients in SDCPM group and 167 (11.62%) patients in CM group (adjusted hazard ratio [HR] = 0.70; [95% confidence interval [CI] 0.55 - 0.89]; p = 0.003). The secondary endpoint occurred in 144 (9.84%) patients in SDCPM group and 197 (13.71%) patients in CM group (adjusted HR = 0.66; [95% CI 0.53 - 0.82]; p < 0.001). The SAQ score in SDCPM group was higher than CM group (366.78 ± 70.19 vs 356.43 ± 73.80, p < 0.001). There were no significant differences of adverse events between two groups. CONCLUSION: In patients following PCI due to ACS, SDCPM in addition to CM treatment reduced the primary and secondary endpoints, as well as improved the quality of life without adverse events.
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Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Humanos , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/etiologia , Estudos de Coortes , Intervenção Coronária Percutânea/efeitos adversos , Estudos Prospectivos , Qualidade de Vida , Resultado do TratamentoRESUMO
The polysulfide (PS) dissolution and low conductivity of lithium sulfides (Li2 S) are generally considered the main reasons for limiting the reversible capacity of the lithium-sulfur (Li-S) system. However, as the inevitable intermediate between PSs and Li2 S, lithium disulfide (Li2 S2 ) evolutions are always overlooked. Herein, Li2 S2 evolutions are monitored from the operando measurements on the pouch cell level. Results indicate that Li2 S2 undergoes slow electrochemical reduction and chemical disproportionation simultaneously during the discharging process, leading to further PS dissolution and Li2 S generation without capacity contribution. Compared with the fully oxidized Li2 S, Li2 S2 still residues at the end of the charging state. Therefore, instead of the considered Li2 S and PSs, slow electrochemical conversions and side chemical reactions of Li2 S2 are the determining factors in limiting the sulfur utilization, corresponding to the poor reversible capacity of Li-S batteries.
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Lactic acid bacteria (LAB) have exhibited strain/species specificity for different food matrices. We investigated the impact of LAB fermentation on the flavor, chemical profile, and bioactivity of goji juice. The colony counts of five selected strains reached above 8.5 log CFU/mL. The fermentation increased the organic acids, decreased the sugars, and improved the sensory quality of goji juice. The majority of the strains had increased acetic acid, heptanoic acid, ethyl phenylacetate, and linalool levels. Specific strains suppressed α-glucosidase and pancreatic lipase activities and increased the antioxidant activities of fermented goji juice. Based on non-targeted metabolomics and activities, 23 important differential metabolites were screened among 453 metabolites. The quantification results showed that isoquercitrin and m-coumaric content varied among strains, reflecting the strain specificity in flavone and flavonol biosynthesis and phenylalanine, tyrosine, and tryptophan biosynthesis. These findings will provide useful information for fermented goji juice biochemistry research.
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Lactobacillales , Lactobacillales/metabolismo , Fermentação , Sucos de Frutas e Vegetais , Metaboloma , AlimentosRESUMO
Finding guiding principles to optimize properties of quantum anomalous Hall (QAH) insulators is of pivotal importance to fundamental science and applications. Here, we build a first-principles QAH material database of chirality and band gap, explore microscopic mechanisms determining the QAH material properties, and obtain a general physical picture that can help researchers comprehensively understand the QAH data. Our results reveal that the usually neglected Coulomb exchange is unexpectedly strong in a large class of QAH materials, which is the key to resolve experimental puzzles. Moreover, we identify simple indicators for property evaluation and suggest material design strategies to control QAH chirality and gap by tuning cooperative or competing contributions via magnetic codoping, heterostructuring, spin-orbit proximity, etc. The work is valuable to future research of magnetic topological physics and materials.
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To compare the clinical efficacy among different acupuncture and moxibustion therapies on stable angina pectoris (SAP) of coronary heart disease by means of network Meta-analysis. The articles of randomized controlled trial (RCT) for SAP of coronary heart disease treated with acupuncture and moxibustion therapies were searched from PubMed, Web of Science, Cochrane Library, CNKI, Wanfang database and VIP database from May 1, 2002 to May 1, 2022. The quality of them was assessed with the risk of bias assessment tool of Cochrane 5.3, and the network Meta-analysis was undertaken with Stata 13.1 software. A total of 29 articles were included with the acupuncture and moxibustion therapies involved, e.g. acupuncture, acupoint application and moxibustion. In comparison with the simple routine western medication, the effective rate was better on SAP treated with the combined treatments, in which, acupoint application, moxibustion, acupuncture and intradermal needling were combined with routine western medication (P<0.05). Of those combined treatments, the combination of the acupoint application with routine western medication had high probability, suggesting the optimal regimen (area under the curve [SUCRA]=0.711, P<0.05). The effective rate of acupuncture combined with routine western medication for ECG improvement was better than that of routine western medication (P<0.05), and such combined treatment was high in probability, underlying its optimal treatment (SUCRA=0.800, P<0.05). Combined with routine western medication, acupuncture, acupoint application, moxibustion and intradermal needling all improve the clinical efficacy on SAP of coronary heart disease. But, with different outcomes considered, the optimal treatments may be different. It needs more multi-central and large-sample randomized controlled trials to validate these results.
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Doença das Coronárias , Humanos , Metanálise em Rede , Doença das Coronárias/terapiaRESUMO
In this study, the role of Sly-miR171e on post-harvest cold tolerance of tomato fruit was researched. The results showed that overexpression of Sly-miR171e (miR171e-OE) promoted postharvest chilling injury (CI) of tomato fruit at the mature red (MR) and mature green (MG) stage. Contrasted with the wild type (WT) and miR171e-OE fruit, the knockdown of Sly-miR171e (miR171e-STTM) showed a lower CI index, lower hydrogen peroxide (H2O2) content, and higher fruit firmness after harvest. In the fruit of miR171e-STTM, the expression level of GRAS24, CBF1, GA2ox1, and COR, and the GA3 content were ascended, while the expression levels of GA20ox1 and GA3ox1 were descended. The research demonstrated that CI in tomato fruit was alleviated at low temperature storage by silencing Sly-miR171e with short tandem target mimic (STTM) technology. Furthermore, it also provided helpful information for genetic modification of miR171e and control of CI in the postharvest fruit.
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Lithium metal anode possesses overwhelming capacity and low potential but suffers from dendrite growth and pulverization, causing short lifespan and low utilization. Here, a fundamental novel insight of using single-atomic catalyst (SAC) activators to boost lithium atom diffusion is proposed to realize delocalized deposition. By combining electronic microscopies, time-of-flight secondary ion mass spectrometry, theoretical simulations, and electrochemical analyses, we have unambiguously depicted that the SACs serve as kinetic activators in propelling the surface spreading and lateral redistribution of the lithium atoms for achieving dendrite-free plating morphology. Under the impressive capacity of 20 mA h cm-2, the Li modified with SAC-activator exhibits a low overpotential of â¼50 mV at 5 mA cm-2, a long lifespan of 900 h, and high Coulombic efficiencies during 150 cycles, much better than most literature reports. The so-coupled lithium-sulfur full battery delivers high cycling and rate performances, showing great promise toward the next-generation lithium metal batteries.
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Exogenous melatonin confers the chilling tolerance of banana fruit by promoting reactive oxygen species (ROS) scavenging system and inducing the unsaturated fatty acid synthesis. The results showed that melatonin treatment increased the contents of phospholipids, promoted the ROS scavenging enzyme, and restrained the activities of lipoxygenase (LOX), and thus reduced the lipid peroxidation of banana peel. In addition, melatonin treatment increased the flavonoids and proline contents, which was conducive to antioxidant capacity. Interestingly, the enhanced antioxidant capacity is conducive to the stability of unsaturated fatty acids and reduce the enzymatic browning reaction. Moreover, melatonin treatment induced the expression of omega-3/6 fatty acid desaturase and triggered the fatty acid metabolism activity, by which maintained higher contents of unsaturated fatty acid in banana peel. Moreover, melatonin treatment stimulated the accumulation of fatty acids in banana peel, and was involved in alleviating fruit chilling injury.
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Melatonina , Musa , Antioxidantes/análise , Estruturas da Membrana Celular/metabolismo , Ácidos Graxos Insaturados/análise , Armazenamento de Alimentos/métodos , Frutas/química , Melatonina/farmacologia , Musa/metabolismo , Espécies Reativas de Oxigênio/metabolismoRESUMO
Diet is a major driver of the structure and function of the gut microbiota, which influences the host physiology. Alcohol abuse can induce liver disease and gut microbiota dysbiosis. Here, we aim to elucidate whether the well-known traditional health food Goji berry targets gut microbiota to prevent liver injury induced by acute alcohol intake. The results showed that Goji supplementation for 14 days alleviated acute liver injury as indicated by lowering serum aspartate aminotransferase, alanine aminotransferase, pro-inflammatory cytokines, as well as lipopolysaccharide content in the liver tissue. Goji maintained the integrity of the epithelial barrier and increased the levels of butyric acid in cecum contents. Furthermore, we established the causal relationship between gut microbiota and liver protection effects of Goji with the help of antibiotics treatment and fecal microbiota transplantation (FMT) experiments. Both Goji and FMT-Goji increased glutathione (GSH) in the liver and selectively enriched the butyric acid-producing gut bacterium Akkermansia and Ruminococcaceae by using 16S rRNA gene sequencing. Metabolomics analysis of cecum samples revealed that Goji and its trained microbiota could regulate retinoyl ß-glucuronide, vanillic acid, and increase the level of glutamate and pyroglutamic acid, which are involved in GSH metabolism. Our study highlights the communication among Goji, gut microbiota, and liver homeostasis.
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The ability to selectively photoexcite at different Brillouin zone valleys forms the basis of valleytronics and other valley-related physics. Symmetry arguments combined with static lattice first-principles calculations suggest an ideal 100% valley polarization in transition-metal dichalcogenides under circularly polarized light. However, experimental reports of the valley polarization range from 32% to almost 100%. Possible explanations for this discrepancy include phonon-mediated transitions, which would place a fundamental limit to valley polarization, and defect-mediated transitions, which could, in principle, be reduced with cleaner samples. We explore the phonon-mediated fundamental limit by performing calculations of phonon-mediated optical absorption for circularly polarized light entirely from the first principles. We also use group theory to reveal the microscopic mechanisms behind the phonon-mediated excitations, discovering contributions from several individual phonon modes and from multiphonon processes. Overall, our calculations show that the phonon-limited valley polarization is around 70% at room temperature for state-of-the-art valleytronic materials including MoSe_{2}, MoS_{2}, WS_{2}, WSe_{2}, and MoTe_{2}. This fundamental limit implies that sufficiently pure transition-metal dichalcogenides are ideal candidates for valleytronics applications.
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Identifying low-energy conformers with quantum mechanical accuracy for molecules with many degrees of freedom is challenging. In this work, we use the molecular dihedral angles as features and explore the possibility of performing molecular conformer search in a latent space with a generative model named variational auto-encoder (VAE). We bias the VAE towards low-energy molecular configurations to generate more informative data. In this way, we can effectively build a reliable energy model for the low-energy potential energy surface. After the energy model has been built, we extract local-minimum conformations and refine them with structure optimization. We have tested and benchmarked our low-energy latent-space (LOLS) structure search method on organic molecules with 5-9 searching dimensions. Our results agree with previous studies.
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Conformação MolecularRESUMO
Effects of three-point direct correlation on properties of the phase field crystal (PFC) modeling are examined for the control of various ordered and disordered phases and their coexistence in both three-dimensional and two-dimensional systems. Such effects are manifested via the corresponding gradient nonlinearity in the PFC free-energy functional that is derived from classical density functional theory. Their significant impacts on the stability regimes of ordered phases, phase diagrams, and elastic properties of the system, as compared to those of the original PFC model, are revealed through systematic analyses and simulations. The nontrivial contribution from three-point direct correlation leads to the variation of the critical point of order-disorder transition to which all the phase boundaries in the temperature-density phase diagram converge. It also enables the variation and control of system elastic constants over a substantial range as needed in modeling different types of materials with the same crystalline structure but different elastic properties. The capability of this PFC approach in modeling both solid and soft matter systems is further demonstrated through the effect of three-point correlation on controlling the vapor-liquid-solid coexistence and transitions for body-centered cubic phase and on achieving the liquid-stripe or liquid-lamellar phase coexistence. All these provide a valuable and efficient method for the study of structural ordering and evolution in various types of material systems.
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SignificanceQuantum anomalous Hall effect (QAHE) and magnetic skyrmion (SK), as two typical topological states in momentum (K) and real (R) spaces, attract much interest in condensed matter physics. However, the interplay between these two states remains to be explored. We propose that the interplay between QAHE and SK may generate an RK joint topological skyrmion (RK-SK), characterized by the SK surrounded by nontrivial chiral boundary states (CBSs). Furthermore, the emerging external field-tunable CBS in RK-SK could create additional degrees of freedom for SK manipulations, beyond the traditional SK. Meanwhile, external field can realize a rare topological phase transition between K and R spaces. Our work opens avenues for exploring unconventional quantum states and topological phase transitions in different spaces.
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The discovery of the anomalous Hall effect in noncollinear antiferromagnetic metals represents one of the most important breakthroughs for the emergent antiferromagnetic spintronics. The tuning of chemical potential has been an important theoretical approach to varying the anomalous Hall conductivity, but the direct experimental demonstration has been challenging owing to the large carrier density of metals. In this work, an ultrathin noncollinear antiferromagnetic Mn3 Ge film is fabricated and its carrier density is modulated by ionic liquid gating. Via a small voltage of ≈3 V, its carrier density is altered by ≈90% and, accordingly, the anomalous Hall effect is completely switched off. This work thus creates an attractive new way to steering the anomalous Hall effect in noncollinear antiferromagnets.
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Capillary bridges play an important role in the process of cohesion, which is crucial for wet granular media, and engineering of pharmaceuticals and food processing. However, the understanding of capillary bridges at the nanoscale remains unclear because the mechanical performance of nanoscale capillary bridges cannot be fully captured and explained by classical capillary theory. We applied a novel molecular dynamic simulation to investigate the dynamic formation process of nanoscale capillary bridges between quartz asperities. In comparison with classical capillary theory, our results suggested that the application of the toroidal approximation and gorge method will break down at the scale of 1 nm. Below this threshold, a pronounced oscillation in the adhesive force was observed due to inconsistent distribution of water molecules in the capillary bridges. Moreover, we found a non-linear correlation between the adhesive force and the saturation degree. Different from the cohesive stress of sandy soil as a function of saturation degree, we identified an optimal saturation range of 0.5-0.7 instead of 0.2-0.9 for the sandy soil. Our findings enhance the understanding of capillary bridges and provide new insights into the capillary force between particles in the fields of geotechnical engineering, food-process engineering, the pharmaceutical industry and nanotechnology.
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Simulação de Dinâmica Molecular , Água , Nanotecnologia , SoloRESUMO
Creating and manipulating multiple charge states of solitary defects in semiconductors is of essential importance for solitary defect electronics, but is fundamentally limited by Coulomb's law. Achieving this objective is challenging, due to the conflicting requirements of the localization necessary for the sizable band gap and delocalization necessary for a low charging energy. Here, using scanning tunneling microscopy/spectroscopy experiments and first-principles calculations, we realized exotic quinary charge states of solitary defects in two-dimensional intermetallic semiconductor Sn2Bi. We also observed an ultralow defect charging energy that increases sublinearly with charge number rather than displaying the usual quadratic behavior. Our work suggests a promising route for constructing multiple defect-charge states by designing intermetallic semiconductors, and opens new opportunities for developing quantum devices with charge-based quantum states.
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Motifs extracted from nature can lead to significant advances in materials design and have been used to tackle the apparent exclusivity between strength and damage tolerance of brittle materials. Here we present a segmental design motif found in arthropod exoskeleton, in which asymmetrical rotational degree of freedom is used in damage control in contrast to the conventional interfacial shear failure mechanism of existing design motifs. We realise this design motif in a compression-resisting lightweight brittle material, demonstrating a unique progressive failure behaviour that preserves material integrity with 60-80% of load-bearing capacity at >50% of compressive strain. This rotational degree of freedom further enables a periodic energy absorbance pattern during failure yielding 200% higher strength than the corresponding cellular structure and up to 97.9% reduction of post-damage residual stress compared with ductile materials. Fifty material combinations covering 27 types of materials analysed display potential progressive failure behaviour by this design motif, thereby establishing a broad spectrum of potential applications of the design motif for advanced materials design, energy storage/conversion and architectural structures.