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Here, deep sequencing results of the maize transcriptome in leaves and roots were compared under high‐nitrogen (HN) and low‐nitrogen (LN) conditions to identify differentially expressed circRNAs (DECs).Circular RNAs (circRNAs) are covalently closed non‐coding RNA with widely regulatory potency that has been identified in animals and plants. However, the understanding of circRNAs involved in responsive nitrogen deficiency remains to be elucidated.A total of 24 and 22 DECs were obtained from the leaves and roots, respectively. Ten circRNAs were validated by divergent and convergent primers, and 6 DECs showed the same expression tendency validated by reverse transcriptase‐quantitative PCR. Integrating the identified differentially expressed miRNAs, 34 circRNAs could act as miRNA decoys, which might play important roles in multiple biological processes, including organonitrogen compound biosynthesis and regulation of the metabolic process. A total of 51 circRNA‐parent genes located in the genome‐wide association study identified loci were assessed between HN and LN conditions and were associated with root growth and development.In summary, our results provide valuable information regarding further study of maize circRNAs under nitrogen deficiency and provide new insights into screening of candidate genes as well as the improvement of maize regarding nitrogen deficiency resistance. CircRNA–miRNA–mRNA co‐expression networks were constructed to explore the circRNAs that participated in biological development and nitrogen metabolism. [ABSTRACT FROM AUTHOR]

The electro-optical (EO) properties of the ferroelectric relaxor poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer were investigated in the wavelength region from 3 to 5 μm. A large Kerr effect was observed in which a refractive index change of -2.6% can be induced under an electric field of 80 V/μm. When combined with the electrostrictive strain, the terpolymer film exhibits a total -5.6% optical path-length change under a field of 80 V/μm. Calculations based on density functional theory suggest that such a large EO effect was caused mainly by the reorientation of the C–F dipoles under external field in the crystalline region. Furthermore, the results support the notion that in the ferroelectric relaxor terpolymer, there exist nanopolar regions that undergo reorientation under external field and generate the observed electrostrictive strain and EO responses. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this letter, a low-resistance ohmic contact on p-type GaN using an alloy of Ni/Pd/Au is reported. The Mg doped p-type GaN samples were grown by metalorganic chemical vapor deposition with a carrier concentration of 4.1x10[sup 17] cm[sup -3]. The as-grown Mg doped samples were deposited with Ni (20 nm)/Pd (20 nm)/Au (100 nm) and then annealed in air, nitrogen, and oxygen ambient conditions at different annealing temperatures ranging from 350 to 650 °C. Linear I-V ohmic characteristics were observed with specific resistance as low as 1.0x10[sup -4] Ω cm[sup 2] for the samples annealed in oxygen atmosphere. Similar contact metal composition was also deposited on Be-implanted p-type GaN samples with a carrier density of 8.1x10[sup 19] cm[sup -3]. Without further annealing process, the samples show good ohmic contact with a lowest specific resistance of 4.5x10[sup -6] Ω cm[sup 2]. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]