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Abstract Heterotrimeric G-proteins, composed of Gα, Gβ, and Gγ subunits, are involved in the regulation of multiple signaling pathways in plants. OsDEP1 (a Gγ subunit) of rice and TaNBP1 (a Gβ subunit) of wheat are homologs of Arabidopsis AGG3 and AGB1, respectively, which are regulators of grain size and also involved in nitrogen responses. However, the function of Arabidopsis G-proteins in nitrogen utilization under different nitrogen conditions has not been fully investigated. In this study, to evaluate the role of Arabidopsis G-proteins in yield and nitrogen use efficiency (NUE), overexpression transgenic lines AtGPA1, AtAGB1 together with AtAGG1 (AGB1-AGG1), AtAGB1 together with AtAGG2 (AGB1-AGG2), and AtAGB1 together with AtAGG3 (AGB1-AGG3) were created in Brassica napus ‘K407’. Analysis of multiple transgenic B. napus lines showed that overexpression of GPA1, AGB1-AGG1, AGB1-AGG2, or AGB1-AGG3 led to increased biomass of seedling plants, including a well-developed root system, and increased nitrogen uptake under low and high nitrogen conditions. The activity of glutamine synthetase, a key nitrogen assimilating enzyme, and the expression levels of genes that are involved in nitrogen uptake and assimilation were significantly increased in overexpression plants under the low nitrogen condition. These properties enabled overexpression plants to increase the number of seeds per silique by 12–27% only under the low nitrogen condition, effectively improving yield per plant by 9–69% and NUE by 7–49%. These results reveal roles of G-proteins in regulating seed traits and NUE, and provide a strategy that can substantially improve crop yield and NUE. 

ABSTRACT Necrotrophic pathogens cause serious threats to agricultural crops, and understanding the resistance genes and their genetic networks is key to breeding new plant cultivars with better resistance traits. AlthoughAlternaria alternatacauses black spot in important leafy brassica vegetables, and leads to significant loss of yield and food quality, little is known about plant–A. alternatainteractions. In this study, we used a unique and large collection of single, double and triple mutant lines of defence metabolite regulators inArabidopsisto explore how these transcription factors and their epistatic networks may influenceA. alternatainfections. This identified nine novel regulators and 20 pairs of epistatic interactions that modulateArabidopsisplants' defence responses toA. alternatainfection. We further showed that the glucosinolate 4‐methoxy‐indol‐3‐ylmethyl is the only glucosinolate consistently responsive toA. alternatainfection in Col‐0 ecotype. With the further exploration of the regulators and the genetic networks on modulating the accumulation of glucosinolates underA. alternatainfection, an inverted triangle regulatory model was proposed forArabidopsisplants' defence responses at a metabolic level and a phenotypic level. 

In database and large-scale data analytics, recursive aggregate processing plays an important role, which is generally implemented under a framework of incremental compuping and executed synchronously and/or asynchronously. We identify three barriers in existing recursive aggregate data processing. First, the processing scope is largely limited to monotonic programs. Second, checking on conditions for monotonicity and correctness for async processing is sophisticated and manually done. Third, execution engines may be suboptimal due to separation of sync and async execution.In this paper, we lay an analytical foundation for conditions to check if a recursive aggregate program that is mono-tonic or even non-monotonic can be executed incrementally and asynchronously with its correct result. We design and implement a condition verification tool that can automatically check if a given program satisfies the conditions. We further propose a unified sync-async engine to execute these pro-grams for high performance. To integrate all these effective methods together, we have developed a distributed Datalog system, called PowerLog. Our evaluation shows that PowerLog can outperform three representative Datalog systems on both monotonic and non-monotonic recursive programs. 

Abstract Women have made significant contributions to applied physics research and development, and their participation is vital to continued progress. Recognizing these contributions is important for encouraging increased involvement and creating an equitable environment in which women can thrive. This Roadmap on Women in Applied Physics, written by women scientists and engineers, is intended to celebrate women’s accomplishments, highlight established and early career researchers enlarging the boundaries in their respective fields, and promote increased visibility for the impact women have on applied physics research. Perspectives cover the topics of plasma materials processing and propulsion, super-resolution microscopy, bioelectronics, spintronics, superconducting quantum interference device technology, quantum materials, 2D materials, catalysis and surface science, fuel cells, batteries, photovoltaics, neuromorphic computing and devices, nanophotonics and nanophononics, and nanomagnetism. Our intent is to inspire more women to enter these fields and encourage an atmosphere of inclusion within the scientific community. 

Abstract Inspired by protein polymerizations, much progress has been made in making “polymer‐like” supramolecular structures from small synthetic subunits through non‐covalent bonds. A few regulation mechanisms have also been explored in synthetic platforms to create supramolecular polymers and materials with dynamic properties. Herein, a type of reactive regulator that facilitates the dimerization of the monomer precursors through dynamic bonds to trigger the supramolecular assembly from small molecules in an aqueous solution is described. The supramolecular structures are crystalline in nature and the reaction coupled assembly strategy can be extended to a supramolecular assembly of aromatic amide derivatives formed in‐situ. The method may be instructive for the development of supramolecular nanocrystalline materials with desired physical properties. 

Abstract Non‐volatile resistive switching (NVRS) is a widely available effect in transitional metal oxides, colloquially known as memristors, and of broad interest for memory technology and neuromorphic computing. Until recently, NVRS was not known in other transitional metal dichalcogenides (TMDs), an important material class owing to their atomic thinness enabling the ultimate dimensional scaling. Here, various monolayer or few‐layer 2D materials are presented in the conventional vertical structure that exhibit NVRS, including TMDs (MX₂, M=transitional metal, e.g., Mo, W, Re, Sn, or Pt; X=chalcogen, e.g., S, Se, or Te), TMD heterostructure (WS₂/MoS₂), and an atomically thin insulator (h‐BN). These results indicate the universality of the phenomenon in 2D non‐conductive materials, and feature low switching voltage, large ON/OFF ratio, and forming‐free characteristic. A dissociation–diffusion–adsorption model is proposed, attributing the enhanced conductance to metal atoms/ions adsorption into intrinsic vacancies, a conductive‐point mechanism supported by first‐principle calculations and scanning tunneling microscopy characterizations. The results motivate further research in the understanding and applications of defects in 2D materials. 

Abstract 2D materials have attracted much interest over the past decade in nanoelectronics. However, it was believed that the atomically thin layered materials are not able to show memristive effect in vertically stacked structure, until the recent discovery of monolayer transition metal dichalcogenide (TMD) atomristors, overcoming the scaling limit to sub‐nanometer. Herein, the nonvolatile resistance switching (NVRS) phenomenon in monolayer hexagonal boron nitride (h‐BN), a typical 2D insulator, is reported. The h‐BN atomristors are studied using different electrodes and structures, featuring forming‐free switching in both unipolar and bipolar operations, with large on/off ratio (up to 10⁷). Moreover, fast switching speed (<15 ns) is demonstrated via pulse operation. Compared with monolayer TMDs, the one‐atom‐thin h‐BN sheet reduces the vertical scaling to ≈0.33 nm, representing a record thickness for memory materials. Simulation results based on ab‐initio method reveal that substitution of metal ions into h‐BN vacancies during electrical switching is a likely mechanism. The existence of NVRS in monolayer h‐BN indicates fruitful interactions between defects, metal ions and interfaces, and can advance emerging applications on ultrathin flexible memory, printed electronics, neuromorphic computing, and radio frequency switches.