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In this paper, an online adaptive optimal control problem of a class of continuous-time Markov jump linear systems (MJLSs) is investigated by using a parallel reinforcement learning (RL) algorithm with completely unknown dynamics. Before collecting and learning the subsystems information of states and inputs, the exploration noise is firstly added to describe the actual control input. Then, a novel parallel RL algorithm is used to parallelly compute the corresponding N coupled algebraic Riccati equations by online learning. By this algorithm, we will not need to know the dynamic information of the MJLSs. The convergence of the proposed algorithm is also proved. Finally, the effectiveness and applicability of this novel algorithm is illustrated by two simulation examples. [ABSTRACT FROM AUTHOR]

Key message: The mutated LsTT2 and Ls2OGD genes are responsible for white seeds and yellow seeds in lettuce, respectively. Three LsCHS genes are involved in the biosynthesis of flavonoid in seed coats. Lettuce seeds have several different colors, including black, yellow, and white. The genetic mechanisms underlying color variations of lettuce seeds remain unknown. We used genome-wide association studies (GWAS) and map-based cloning approaches to clone genes controlling the color of lettuce seeds. LsTT2, which encodes an R2R3-MYB transcription factor and is homologous to the TT2 gene in Arabidopsis, was shown to be the causal gene for the variation of black and white seeds in lettuce. A point mutation leads to the lack of stop codon in the LsTT2 transcript, resulting in white seeds. Knockout of the LsTT2 gene converted black seeds to white seeds. The locus controlling yellow seeds was mapped to Chromosome 2. Knockout of two 2-oxoglutarate-dependent dioxygenases (2OGD) genes from the candidate region converted black seeds to yellow seeds, suggesting that these two 2OGD proteins catalyze the conversion of yellow metabolites to black metabolites. We also showed that three LsCHS genes from the candidate region are associated with flavonoid biosynthesis in seeds. Knockout mutants of the three LsCHS genes decreased color intensity. This study provides new insights into the regulation of flavonoid biosynthesis in plants. [ABSTRACT FROM AUTHOR]

This paper studies the robust stochastic stability problem for a class of Markov jump systems with norm bounded uncertain parameters and distributed time-delays. Integral inequality techniques together with Lyapunov-Krasovskii functional approach are employed to develop new delay-dependent sufficient conditions for stochastic stability. The main results are derived via linear matrix inequalities formulation. Simulation examples illustrate the effectiveness of the developed techniques. [ABSTRACT FROM AUTHOR]

In this paper, the novel fluorescence probe XP based on Schiff-base was designed, synthesized and characterized, which could detect Y3+selectively and sensitively. The recognition mechanism of XP toward Y3+ was studied by Job's plot and HRMS. It was investigated that stoichiometric ratio of the probe XP conjugated with Y3+ was 1:2. And the detection limit was calculated as 0.30 μM. In addition, Y3+ was recognized by the test paper made from XP. And the probe XP could detect Y3+ selectively in Caenorhabditis elegans and the main organs of mice. Thus, XP was considered to have some potential for application in bioimaging. [ABSTRACT FROM AUTHOR]

In this paper, a novel scheme for the tracking problem of nonlinear systems is proposed. First, as a new technology of neural network in control field, linear differential inclusion is used to approximate the nonlinear term for the entire system. Based on the equivalent linear system, tracking reference signal is given and a new augmented system is built. According to the mentioned value function, two reinforcement learning algorithms are proposed to design the optimal control law. Notice that the online algorithm does not involve the system dynamics and tracking dynamics. In the simulation section, the model of trolley system is given to prove the effectiveness and accuracy of the scheme proposed in this paper. [ABSTRACT FROM AUTHOR]

A 2-year field experiment was conducted to analyze the growth conditions, physical features, yield, and nitrogen use efficiency (NUE) of sugar-beet under limited irrigation conditions in northeast of China. A cultivar H003 was used as plant materials; six treatments (C1–C6) were included: C1, no nitrogen applied, rain-fed; C2, nitrogen (120.00 kg ha−1), rain-fed; C3, no nitrogen applied, hole irrigation for seeding; C4, nitrogen (120.00 kg ha−1), hole irrigation for seeding; C5, no nitrogen applied, hole irrigation for seeding; and C6, nitrogen (120.00 kg ha−1), hole irrigation for seeding, and irrigation at foliage rapid growth stage. The irrigation supply was only 500 mL/plant once. Results showed C6 showed the highest chlorophyll content, dry matter accumulation, yield, etc. and had the best NUE among all the treatments. In conclusion, under the routine fertilization conditions of northeast of China, the cultivation measure of hole irrigation 500 mL/plant for seeding combined with irrigation 500 mL/plant at foliage rapid growth stage greatly improved sugar-beet yield and NUE. [ABSTRACT FROM AUTHOR]