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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.