Optical neural networks (ONNs), enabling low latency and high parallel data processing withoutelectromagnetic interference, have become a viable player for fast and energy-efficient processing andcalculation to meet t...Optical neural networks (ONNs), enabling low latency and high parallel data processing withoutelectromagnetic interference, have become a viable player for fast and energy-efficient processing andcalculation to meet the increasing demand for hash rate. Photonic memories employing nonvolatile phase-change materials could achieve zero static power consumption, low thermal cross talk, large-scale, andhigh-energy-efficient photonic neural networks. Nevertheless, the switching speed and dynamic energyconsumption of phase-change material-based photonic memories make them inapplicable for in situ training.Here, by integrating a patch of phase change thin film with a PIN-diode-embedded microring resonator,a bifunctional photonic memory enabling both 5-bit storage and nanoseconds volatile modulation wasdemonstrated. For the first time, a concept is presented for electrically programmable phase-changematerial-driven photonic memory integrated with nanosecond modulation to allow fast in situ training and zerostatic power consumption data processing in ONNs. ONNs with an optical convolution kernel constructedby our photonic memory theoretically achieved an accuracy of predictions higher than 95% when testedby the MNIST handwritten digit database. This provides a feasible solution to constructing large-scalenonvolatile ONNs with high-speed in situ training capability.展开更多
Late blight is the most devastating potato disease and it also causes serious yield loss in tomato. Several disease resistance genes (R genes) to late blight have been cloned from potato in the past decade. However,...Late blight is the most devastating potato disease and it also causes serious yield loss in tomato. Several disease resistance genes (R genes) to late blight have been cloned from potato in the past decade. However, the resistance mechanisms remain elusive. Tomato and potato belong to the botanical family Solanaceace and share remarkably conserved genome structure. Since tomato is a model system in genetic and plant pathology research, we used tomato to develop a powerful mutant screening system that will greatly facilitate the analysis of the signaling pathway of resistance to Phytophthora infestans. First we proved that the R3a transgenic tomatoes developed specific hypersensitive cell death response (HR) to P. infestans strains carrying the corresponding avirulence gene Avr3a, indicating that the signaling pathway from the R3a-Avr3a recognition to HR is conserved between potato and tomato. Second, we generated transgenic tomatoes carrying both R3a and Avr3a genes, with the latter under the control of a glucocorticiod-inducible promoter. Dexamethasone induced expression of Avr3a and resulted in localized HR. This versatile system can be used to construct a mutant library to screen surviving mutants whose resistance signal transduction was interrupted, providing the basis to identify key genes involved in the resistance to late blight in Solanaceae.展开更多
基金supported by the National Key Research and Development Program of China (2019YFB2203002 and 2021YFB2801300)National Natural Science Foundation of China (62105287, 91950204, and 61975179)Zhejiang Provincial Natural Science Foundation (LD22F040002)
文摘Optical neural networks (ONNs), enabling low latency and high parallel data processing withoutelectromagnetic interference, have become a viable player for fast and energy-efficient processing andcalculation to meet the increasing demand for hash rate. Photonic memories employing nonvolatile phase-change materials could achieve zero static power consumption, low thermal cross talk, large-scale, andhigh-energy-efficient photonic neural networks. Nevertheless, the switching speed and dynamic energyconsumption of phase-change material-based photonic memories make them inapplicable for in situ training.Here, by integrating a patch of phase change thin film with a PIN-diode-embedded microring resonator,a bifunctional photonic memory enabling both 5-bit storage and nanoseconds volatile modulation wasdemonstrated. For the first time, a concept is presented for electrically programmable phase-changematerial-driven photonic memory integrated with nanosecond modulation to allow fast in situ training and zerostatic power consumption data processing in ONNs. ONNs with an optical convolution kernel constructedby our photonic memory theoretically achieved an accuracy of predictions higher than 95% when testedby the MNIST handwritten digit database. This provides a feasible solution to constructing large-scalenonvolatile ONNs with high-speed in situ training capability.
基金Dr Sophien Kaumoun from The Sainsbury Laboratory for providing pGR106:Avr3a23-147Dr Chua Nam-Hai at Rockefeller University for providing vector pTA7002Supported by the National Natural Science Foundation of China(30671319)
文摘Late blight is the most devastating potato disease and it also causes serious yield loss in tomato. Several disease resistance genes (R genes) to late blight have been cloned from potato in the past decade. However, the resistance mechanisms remain elusive. Tomato and potato belong to the botanical family Solanaceace and share remarkably conserved genome structure. Since tomato is a model system in genetic and plant pathology research, we used tomato to develop a powerful mutant screening system that will greatly facilitate the analysis of the signaling pathway of resistance to Phytophthora infestans. First we proved that the R3a transgenic tomatoes developed specific hypersensitive cell death response (HR) to P. infestans strains carrying the corresponding avirulence gene Avr3a, indicating that the signaling pathway from the R3a-Avr3a recognition to HR is conserved between potato and tomato. Second, we generated transgenic tomatoes carrying both R3a and Avr3a genes, with the latter under the control of a glucocorticiod-inducible promoter. Dexamethasone induced expression of Avr3a and resulted in localized HR. This versatile system can be used to construct a mutant library to screen surviving mutants whose resistance signal transduction was interrupted, providing the basis to identify key genes involved in the resistance to late blight in Solanaceae.