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Leaf flattening plays a vital role in the establishment of plant architecture, which is closely related to plant photosynthesis and, thus, influences the product yield and quality of Chinese cabbage. In this study, we used the doubled haploid line ‘FT’ of Chinese cabbage as the wild type for ethyl methanesulfonate (EMS) mutagenesis and obtained a mutant cwm with stably inherited compact and wrinkled leaves. Genetic analysis revealed that the mutated trait was controlled by a single recessive nuclear gene, Brcwm. Brcwm was preliminarily mapped to chromosome A07 based on bulked segregant RNA sequencing (BSR-seq) and fine-mapped to a 205.66 kb region containing 39 genes between Indel12 and Indel21 using SSR and Indel analysis. According to the whole-genome re-sequencing results, we found that there was only one nonsynonymous single nucleotide polymorphism (SNP) (C to T) within the target interval on exon 4 of BraA07g021970.3C, which resulted in a proline to serine amino acid substitution. The mutated trait co-segregated with the SNP. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) revealed that BraA07g021970.3C expression was dramatically higher in ‘FT’ leaves than that in cwm leaves. BraA07g021970.3C is homologous to AT3G55000 encoding a protein related to cortical microtubule organization. A similar phenotype of dwarfism and wrinkled leaves was observed in the recessive homozygous mutant cwm-f1 of AT3G55000, and its T3 transgenic lines were restored to the Arabidopsis wild-type phenotype through ectopic overexpression of BraA07g021970.3C. These results verified that BraA07g021970.3C was the target gene essential for leaf flattening in Chinese cabbage.

Leafy head is an important agronomic trait that determines the yield and quality of Chinese cabbage. The molecular mechanism underlying heading in Chinese cabbage has been the focus of research, and wide leaves are a prerequisite for leafy head formation. In our study, two allelic leafy heading-deficient mutants (lhd1 and lhd2) with narrow leaf phenotypes were screened in an ethyl methanesulfonate mutagenized population from a heading Chinese cabbage double haploid line ‘FT’. Genetic analysis revealed that the mutant trait was controlled by a recessive nuclear gene, which was found to be BraA10g000480.3C by MutMap and Kompetitive allele-specific PCR analyses. As BraA10g000480.3C was the ortholog of ANGUSTIFOLIA in Arabidopsis, which has been found to regulate leaf width by controlling cortical microtubule arrangement and pavement cell shape, we named it BrAN. BrAN in mutant lhd1 carried an SNP (G to A) on intron 2 that co-segregated with the mutant phenotype, and disrupted the exon-intron splice junction generating intron retention and a putative truncated protein. BrAN in mutant lhd2 carried an SNP (G to A) on exon 4 leading to a premature stop codon. The ectopic overexpression of BrAN restored normal leaf phenotype due to abnormal cortical microtubule arrangement and pavement cell shape in the Arabidopsis an-t1 mutant. However, transformation of Bran did not rescue the an-t1 phenotype. These results indicate that BrAN contributes to leafy head formation of Chinese cabbage.

Described in this paper is fiber optic gyroscopes for harsh environment applications. The fiber optic gyroscope consists of a super luminescent diode, a fiber coupler, a polarizing optical fiber coil, a detector and a signal-processing device. The peak wavelength of SLD is 1.3 micrometer. The multifunctional integrated optical circuit that includes a polarizater, a Y type junction coupler and a phase modulator, is manufactured with annealed proton exchange process. The polarizing optic fiber coil is fabricated by applying quadrupolar winding technology. The fiber optic gyroscope can work in high/low temperature, large acceleration, vibration, shock and other harsh environments. It is applied in aircraft inertial navigation systems and directional measuring system in oil-rigs.

A re-entrant fiber optic gyro (RE-FOG) that utilizes a ring resonator (RR) and a low-coherence length light source is designed and demonstrated. A reflector is placed on one end of input/output directional coupler to realize light beams propagating in CW and CCW directions. RE-FOG promises a higher sensitivity than the conventional Sagnac interferometer fiber optic gyro (I-FOG) without the disadvantages of a resonant fiber optic gyro (R-FOG). Theoretical considerations of the sensitivity and the resolution of RE-FOG are discussed. Experimental results (the constant bias of 0.2 deg/h and the variance of random drift rate better than 0.1 deg/h) are also presented.

This report describes a fiber-optic rotation sensor particularly adapted to be placed adjacent a drill head to measure the orientation of a drill during or after drilling for minerals such as oil and gas.

This report describes the closed-loop fiber optic gyroscope for aircraft strap-down navigation systems. The closed-loop fiber optic gyroscope consists of a super luminescent diode, a fiber coupler, an integrated optical circuit, a polarizing fiber optic coil, a photoelectric detector and a signal processing circuit. The report describes several technical ways to improve the precision of the closed-loop fiber optic gyro: by improving properties and stability of the integrated optical circuit, utilizing a polarizing fiber optic coil using four grade symmetry twining round technology, improving the properties and stability of the light source, and by using a digital signal processing circuit.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This report describes closed-loop fiber optic gyroscope and related components for aircraft strap-down inertial navigation system. The closed-loop fiber optic gyroscope consists of super luminescent diode with working wavelength 1.3micrometers , fiber coupler, polarizing optical fiber coil which was fabricated by similar rectangle polarizing optical fiber with length of 500m by applying four grades symmetry twining round technology, photoelectric detector, and an integrated optical circuit (IOC) phase modulator fabricated with annealed proton and signal processing circuit technology.