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OsMADS1 plays a vital role in regulating floret development and grain shape, but whether it regulates rice grain quality still remains largely unknown. Therefore, we used comprehensive molecular genetics, plant biotechnology, and functional omics approaches, including phenotyping, mapping-by-sequencing, target gene seed-specific RNAi, transgenic experiments, and transcriptomic profiling to answer this biological and molecular question. Here, we report the characterization of the 'Oat-like rice' mutant, with poor grain quality, including chalky endosperms, abnormal morphology and loose arrangement of starch granules, and lower starch content but higher protein content in grains. The poor grain quality of Oat-like rice was found to be caused by the mutated OsMADS1Olr allele through mapping-by-sequencing analysis and transgenic experiments. OsMADS1 protein is highly expressed in florets and developing seeds. Both OsMADS1-eGFP and OsMADS1Olr-eGFP fusion proteins are localized in the nucleus. Moreover, seed-specific RNAi of OsMADS1 also caused decreased grain quality in transgenic lines, such as the Oat-like rice. Further transcriptomic profiling between Oat-like rice and Nipponbare grains revealed that OsMADS1 regulates gene expressions and regulatory networks of starch and storage protein metabolisms in rice grains, hereafter regulating rice quality. In conclusion, our results not only reveal the crucial role and preliminary mechanism of OsMADS1 in regulating rice grain quality but also highlight the application potentials of OsMADS1 and the target gene seed-specific RNAi system in improving rice grain quality by molecular breeding. [ABSTRACT FROM AUTHOR]

Salt–alkali stress threatens the resilience to variable environments and thus the grain yield of rice. However, how rice responds to salt–alkali stress at the molecular level is poorly understood. Here, we report isolation of a novel salt–alkali-tolerant rice (SATR) by screening more than 700 germplasm accessions. Using 93-11, a widely grown cultivar, as a control, we characterized SATR in response to strong salt–alkali stress (SSAS). SATR exhibited SSAS tolerance higher than 93-11, as indicated by a higher survival rate, associated with higher peroxidase activity and total soluble sugar content but lower malonaldehyde accumulation. A transcriptome study showed that cell wall biogenesis-related pathways were most significantly enriched in SATR relative to 93-11 upon SSAS. Furthermore, higher induction of gene expression in the cell wall matrix polysaccharide biosynthesis pathway, coupled with higher accumulations of hemicellulose and pectin as well as measurable physio-biochemical adaptive responses, may explain the strong SSAS tolerance in SATR. We mapped SSAS tolerance to five genomic regions in which 35 genes were candidates potentially governing SSAS tolerance. The 1,4-β-D-xylan synthase gene OsCSLD4 in hemicellulose biosynthesis pathway was investigated in details. The OsCSLD4 function-disrupted mutant displayed reduced SSAS tolerance, biomass and grain yield, whereas the OsCSLD4 overexpression lines exhibited increased SSAS tolerance. Collectively, this study not only reveals the potential role of cell wall matrix polysaccharides in mediating SSAS tolerance, but also highlights applicable value of OsCSLD4 and the large-scale screening system in developing SSAS-tolerant rice. [ABSTRACT FROM AUTHOR]

Wear debris in lubrication oil provides important information for marine engine condition monitoring and faults diagnosis. Inductive sensors have been widely used to detect wear debris in lubrication oil. To improve the sensitivity, the inductive coil is always connected with a capacitor in parallel to form parallel LC resonance-sensing circuit. A previous study optimized the parallel resonance circuit by adjusting the excitation frequency. However, multiple parameters (namely, excitation signal, signal detection circuits, and signal-processing program, etc.) need to be adjusted accordingly for a series of the testing frequencies. To simplify the optimization, we propose a method based on adjusting the parallel capacitance in this work. The impedance (inductance and internal resistance) of the sensing coil and its variation induced by particles are first measured, which are the necessary parameters for establishing the function relationship between the parallel capacitance and the relative impedance variation. With the function relationship, the relative impedance variation is calculated directly, and the optimal capacitance is located at the highest absolute value of it. The experimental results for the ferrous and nonferrous particles match the calculation results well. Interestingly, the optimal capacitance for the nonferrous particle was larger than that of the ferrous particle. We speculate that the difference is generated due to the increased resistance induced by the eddy current effect. [ABSTRACT FROM AUTHOR]

Inductance detection is an important method for detecting wear debris in ship lubricating oil. Presently, an LCR (inductance, resistance, capacitance) meter is generally used to detect wear debris by measuring the inductance change of the sensing coil. When ferromagnetic debris passes through the sensing coil, a pulse will appear in the inductance signal. Previous studies have shown that the amplitude of the inductance pulse decreases significantly with the increase in the particles' velocity. Therefore, it is difficult to detect ferromagnetic debris with a high flow velocity using an LCR meter. In this paper, a novel method, high-frequency voltage acquisition (HFVA), is proposed to detect ferromagnetic debris. Different from previous methods, the wear debris was detected directly by measuring the voltage change of the sensing coil, while the synchronized sampling method was utilized to ensure the higher-frequency acquisition of the sensor output signal. The experimental results show that when the velocity of particles increased from 6 mm/s to 62 mm/s, the amplitude of the signal pulse obtained by HFVA decreased by only 13%, which was much lower than the 85% obtained by utilizing the LCR method. [ABSTRACT FROM AUTHOR]

Wear debris detection is an effective method to determine the running state of the machine. Recently, the planar inductor is commonly used to detect wear debris. The previous studies have found that the inductive signal would be varied while changing the position of wear debris pass through. However, the effect of position on the wear debris detection is not well understood. In this paper, a novel detection system in which the position of wear debris pass through could be adjusted precisely is designed. By changing the position in horizontal or vertical direction, the inductive signals of the wear debris were acquired. In the horizontal direction, the experimental results show that the amplitude of the inductive signal first increases and then decreases when the position changes from the center of the planar inductor to the outer. The maximum inductive signal appears when the wear debris pass through the edge of the inner coil, which is 20% higher than that for the center and much higher than that for the edge of outer coil. In the vertical direction, the signal decreases almost linearly when the position is away from the planar inductor. For every 0.1 mm step far away the planar inductor, the signal amplitude drops by approximately 10%. The variation trend of our experimental results is consistent with the numerical simulation results of magnetic intensity around the planar inductor. [ABSTRACT FROM AUTHOR]

To estimate the reaction free energies of the hydrogen evolution reaction (HER) on under-coordinated metallic sites, density function theory (DFT) calculations are usually employed to calculate the hydrogen adsorption energy with an "only-one-hydrogen-adsorption" model, assuming that adsorption with one hydrogen is the most thermodynamically favorable situation during catalysis. In this brief report, we show that on many single atom sites, adsorption of more than one hydrogen is sometimes even more thermodynamically favorable, with the presence of two or three hydrogens resulting in lower adsorption energies. These interesting non-monotonic trends indicate that modeling HER and other hydrogen-related reactions on under-coordinated sites should also consider the numbers of hydrogen being adsorbed at the same site, otherwise the results could deviate from real experimental situations. [ABSTRACT FROM AUTHOR]

Vacuolar invertase is involved in sugar metabolism and plays a crucial role in plant growth and development, thus regulating seed size. However, information linking vacuolar invertase and seed size in rice is limited. Here we characterized a small grain mutant sg2 (grain size on chromosome 2) that showed a reduced in grain size and 1000-grain weight compared to the wild type. Map-based cloning and genetic complementation showed that OsINV3 is responsible for the observed phenotype. Loss-of-function of OsINV3 resulted in grains of smaller size when compared to the wild type, while overexpression showed increased grain size. We also obtained a T-DNA insertion mutant of OsINV2, which is a homolog of OsINV3 and generated double knockout (KO) mutants of OsINV2 and OsINV3 using CRISPR/Cas9. Genetic data showed that OsINV2, that has no effect on grain size by itself, reduces grain length and width in the absence of OsINV3. Altered sugar content with increased sucrose and decreased hexose levels, as well as changes vacuolar invertase activities and starch constitution in INV3KO, INV2KO, INV3KOINV2KO mutants indicate that OsINV2 and OsINV3 affect sucrose metabolism in sink organs. In summary, we identified OsINV3 as a positive regulator of grain size in rice, and while OsINV2 has no function on grain size by itself. In the absence of OsINV3, it is possible to detect a role of OsINV2 in the regulation of grain size. Both OsINV3 and OsINV2 are involved in sucrose metabolism, and thus regulate grain size. Our findings increase our understanding of the role of OsINV3 and its homolog, OsINV2, in grain size development and also suggest a potential strategy to improve grain yield in rice. [ABSTRACT FROM AUTHOR]

Sensitivity is an important performance index for evaluating surface plasmon resonance (SPR) biosensors. Sensitivity enhancement has always been a hot topic. It is found that the different refractive indices of samples require different combinations of prism and metal film for better sensitivity. Furthermore, the sensitivity can be enhanced by coating two-dimensional (2D) materials with appropriate layers on the metal film. At this time, it is necessary to choose the best film configuration to enhance sensitivity. With the emergence of more and more 2D materials, selecting the best configuration manually is becoming more complicated. Compared with the traditional manual method of selecting materials and layers, this paper proposes an optimization method based on a genetic algorithm to quickly and effectively find the optimal film configuration that enhances sensitivity. By using this method, not only can the optimal number of layers of 2D materials be determined quickly, but also the optimal configuration can be conveniently found when many materials are available. The maximum sensitivity can reach 400°/RIU after optimization. The method provided application value for the relevant researchers seeking to enhance sensitivity. [ABSTRACT FROM AUTHOR]

Evaporative cooling is a green, energy-efficient cooling technology adopted in hot and dry regions, which has wider application in the field of air-conditioning systems. Outdoor meteorological parameters have a great influence on the operation mode and control strategy of evaporative cooling air-conditioning systems, and the system load distribution and system configuration will be affected. This paper aims at investigating the load distribution of semi-central evaporative cooling air-conditioning systems under the condition of hourly outdoor meteorological parameters. Firstly, this paper introduced the design partition, operation mode, controlling strategy and load distribution method on semi-central evaporative cooling air-conditioning system. Then, taking an office building in Lanzhou (China) as an example, the evaporative cooling air-conditioning system was divided into five regions and the load distribution was simulated by TRNSYS (The Transient Energy System Simulation Tool) under the condition of hourly outdoor meteorological parameters. Finally, the results have shown that the evaporative cooling air-conditioning system can provide 25.46% of the building loads, which was of great significance to reduce the energy consumption of air-conditioning system. [ABSTRACT FROM AUTHOR]