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Reliable and scalable micro-valves on flexible materials are attractive for fluid management and enhanced device functionality for disposable microfluidic applications. Here, a microfluidic electrowetting valve was fabricated on a poly(ethylene terephthalate) substrate based on the principle of electrowetting-on-dielectric. Copper electrodes were fabricated by inkjet-printing a copper oxide nanoparticle ink and rapidly reduced to conductive copper using intense pulsed light sintering. A hydrophilic and a hydrophobic electrode are required for low-voltage actuation of the valve. To produce the hydrophobic electrode, poly(perfluorooctyl methacrylate) was uniformly coated over the copper electrode via initiated chemical vapor deposition. Systematic experiments were performed to study the effect of dielectric layer thicknesses and applied voltages on the droplet contact angle. Electrodes with dielectric layers of 14, 38, and 92 nm were actuated at 2 V, and at the same applied voltage, the droplet contact angle decreased fastest for electrodes coated with the thinnest dielectric layers. Polymer-coated copper electrodes were demonstrated to remain stable throughout a 3-month aging study at ambient conditions and showed consistent wetting behavior at low voltages. Furthermore, a microfluidic device was fabricated using laser cut parts to demonstrate separate actuation of two electrowetting valves at an applied voltage of 3 V. These results offer compelling opportunities for integration of copper electrowetting valves into low-cost microfluidic devices using scalable techniques. [ABSTRACT FROM AUTHOR]

The family of phosphate transporters (PHTs) mediates the uptake and translocation of Pi inside the plants. However, little is known about transporters in soybean. Therefore, Searched the Genome Database for Soybean, 57 GmPHTs family members were identified in soybean, Phylogenetic analysis suggested that members of the PHTs gene family can be divided into six clades. Collinearity analysis revealed that most of the GmPHT genes shared syntenic relationships with PHTs members in Arabidopsis thaliana and that large segment duplication played a major driving force for GmPHTs evolution in addition to tandem duplication. Further analysis of the promoter revealed that light-responsive elements and abiotic stress-responsive elements were widely distributed within the promoter regions of GmPHT genes. Based on RNA-seq data, GmPHTs showed different expression patterns in roots and leaves of soybean treated with long-term low phosphorus and short-term low phosphorus, in addition, the expression levels of GmPHT genes can be regulated by drought stresses, it was implied that the induced expression of GmPHTs could promote phosphorus uptake and transport in soybean and thus adapt to low phosphorus and drought stress, which is the first step dissection of Pi transport system and probably refers to new roles of PHTs genes in soybean. [ABSTRACT FROM AUTHOR]

This study used the rice cultivar Suijing 18 to investigate the effects of morphological characteristics, photosynthetic changes, yield, as well as nitrogen absorption and utilization. The interaction between seeding rate and nitrogen rate was also assessed to identify the most suitable values of the dominant population for both factors under dry cultivation. Furthermore, the photosynthetic physiological characteristics of the upper three leaves in the dominant population were also explored. The results showed that a combination of 195 kg/ha seeding rate and 140 kg/ha nitrogen rate achieved high yield, high nitrogen utilization, and moderate morphological characteristics. This was achieved by a coordination of the combined advantages of population panicle number and spikelets per panicle. The photosynthetic potential of the population was improved by coordinating the reasonable distribution of light energy in the upper three leaves, which led to the emergence of a dominant rice population under dry cultivation. [ABSTRACT FROM AUTHOR]

This study was aimed to clarify the effects of the interaction between water and nitrogen on grain yield and greenhouse gases (GHGs) emissions under straw incorporation (SI) in a rice paddy field in northeast China. Under standard local rice paddy fields conditions, a split-plot design was used, with continuous flooding (CF) irrigation and alternate wetting and drying (AWD) irrigation as primary plot treatments, and traditional nitrogen application management (TNAM, basal fertilizer:tiller fertilizer:panicle fertilizer:spikelet fertilizer, 6:3:1:0), postponed nitrogen topdressing management 1 (PNTM1, basal fertilizer:tiller fertilizer:panicle fertilizer:spikelet fertilizer, 5:2:2:1), and postponed nitrogen topdressing management 2 (PNTM2, basal fertilizer:tiller fertilizer:panicle fertilizer:spikelet fertilizer, 4:3:2:1) as secondary plot treatments. The cumulative GHGs emissions, global warming potential (GWP), and grain yield at each reproductive stage under interactions between water and nitrogen were examined. Compared with CF, the grain yield of AWD in 2018 and 2019 increased significantly by 8.84% and 9.93%, respectively. There was no significant difference in grain yield between different nitrogen management practices under the same irrigation pattern. Compared with CF, AWD reduced CO2 and CH4 emissions by 27.82% and 47.96%, increased N2O emissions by 18.78%, and reduced the GWP and greenhouse gas intensity (GHGI) by 38.27% and 44.18%. Under AWD, there were no significant differences in CH4 emissions and GHGI between different nitrogen management treatments, and PNTM1 and PNTM2 significantly reduced CO2 emissions by 36.55% and 22.99%, increased N2O emissions by 70.59% and 76.47%, and significantly reduced GWP by 29.51% and 19.73%, respectively. Compared to TNAM, with PNTM1 achieving better emission reduction than PNTM2. Thus, AWD with PNTM1 under SI had the most significant abatement effect with stable grain yields. Thus, emission reductions can be achieved through utilizing the interaction between water and nitrogen under SI to ensure sustainable rice production in agricultural areas like those of central Jilin province. [ABSTRACT FROM AUTHOR]