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Li, Zhigang

Publications and source records attributed to Li, Zhigang.

11 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Genome resources for three modern cotton lines guide future breeding efforts

Cotton ( Gossypium hirsutum L.) is the key renewable fibre crop worldwide, yet its yield and fibre quality show high variability due to genotype-specific traits and complex interactions among cultivars, management practices and environmental factors. Modern breeding practices may limit future yield gains due to a narrow founding gene pool. Precision breeding and biotechnological approaches offer potential solutions, contingent on accurate cultivar-specific data. Here we address this need by generating high-quality reference genomes for three modern cotton cultivars (‘UGA230’, ‘UA48’ and ‘CSX8308’) and updating the ‘TM-1’ cotton genetic standard reference. Despite hypothesized genetic uniformity, considerable sequence and structural variation was observed among the four genomes, which overlap with ancient and ongoing genomic introgressions from ‘Pima’ cotton, gene regulatory mechanisms and phenotypic trait divergence. Differentially expressed genes across fibre development correlate with fibre production, potentially contributing to the distinctive fibre quality traits observed in modern cotton cultivars. These genomes and comparative analyses provide a valuable foundation for future genetic endeavours to enhance global cotton yield and sustainability.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

A Systematic Study on the Dynamic Softening Behavior of a Heat-Resistant Alloy Considering Thermal and Microstructural Effects

Deep understanding of the relationships among flow softening behaviors, microstructure evolution and process parameters is an essential issue due to the varied strain rate and temperature in industrial hot working schedules. In this research, substantial hot compression tests of a SNCrW heat-resistant alloy were conducted to quantitatively investigate the extrinsic dynamic flow softening behaviors and intrinsic grain size evolution. The thermal softening ratio (TSR) and microstructural softening ratio (MSR) were introduced to, respectively, characterize the degree of deformation heating-induced thermal softening and dynamic recrystallization-induced microstructural softening, respectively. To obtain more accurate results, the TSR was calculated with an improved algorithm that considered strain effects. Additionally, a 3D TSR map and MSR map of the SNCrW heat-resistant alloy were constructed to study the response relationships between thermal softening or microstructural softening and the deformation parameters. In addition, a superimposed contour map of the average grain size on the MSR map was developed to reveal the relationships between microstructural evolution and the macromechanical response. The results show that the grain size of the SNCrW heat-resistant alloy exhibits an inverse correlation with the MSR and is slightly correlated with thermal softening.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Broadband infrared binary-pattern metasurface absorbers with micro-genetic algorithm optimization

Broadband binary-pattern metasurface absorbers are designed and demonstrated in the mid-infrared wavelength range through the micro-genetic algorithm. The tungsten-based metasurface absorbers with the optimized binary-pattern nanostructures exhibit broadband near-perfect absorption due to the multiple plasmonic resonances supported within the unit cell. Furthermore, the influence of minor pixel modifications in the optimized binary-pattern nanostructures on the absorption performance is investigated in the experiment. This Letter presents a promising approach to design and optimize complex optical nanostructures with the desired properties for metamaterial and metasurface applications.

42 ENGINEERING↗
DOE OSTI2018

DRMY1, a Myb-Like Protein, Regulates Cell Expansion and Seed Production in Arabidopsis thaliana

Abstract Plant organ development to a specific size and shape is controlled by cell proliferation and cell expansion. Here, we identify a novel Myb-like Arabidopsis gene, Development Related Myb-like1 (DRMY1), which controls cell expansion in both vegetative and reproductive organs. DRMY1 is strongly expressed in developing organs and its expression is reduced by ethylene while it is induced by ABA. DRMY1 has a Myb-like DNA-binding domain, which is predominantly localized in the nucleus and does not exhibit transcriptional activation activity. The loss-of-function T-DNA insertion mutant drmy1 shows reduced organ growth and cell expansion, which is associated with changes in the cell wall matrix polysaccharides. Interestingly, overexpression of DRMY1 in Arabidopsis does not lead to enhanced organ growth. Expression of genes involved in cell wall biosynthesis/remodeling, ribosome biogenesis and in ethylene and ABA signaling pathways is changed with the deficiency of DRMY1. Our results suggest that DRMY1 plays an essential role in organ development by regulating cell expansion either directly by affecting cell wall architecture and/or cytoplasmic growth or indirectly through the ethylene and/or ABA signaling pathways.

Cell Biology↗
DOE OSTI2016

Measurement of a redshift-space power spectrum for BOSS galaxies and the growth rate at redshift 0.57

We present a measurement of the two-dimensional (2D) redshift-space power spectrum for the Baryon Oscillation Spectroscopic Survey Data Release 11 CMASS galaxies in the northern Galactic cap based on the method developed by Jing and Börner. In this method, we first measure the 2D redshift-space correlation function and obtain the 2D power spectrum based on Fourier transform of the correlation function. The method is tested with an N-body mock galaxy catalog, which demonstrates that the method can yield an accurate and unbiased measurement of the redshift-space power spectrum given that the input 2D correlation function is correct. Compared with previous measurements in literature that are usually based on direct Fourier transform in redshift space, our method has the advantages that the window function and shot noise are fully corrected. Thus, our measurement can facilitate a direct comparison with the theoretical predictions. Our 2D power spectrum, by construction, can reproduce the 2D correlation function, and it can reproduce, for example, the 2D power spectrum of Beutler et al. accurately if ours is convolved with the window function they provided. We then develop a method to measure the structure growth rate, by separating the anisotropic redshift-space power spectrum from the isotropic real-space power spectrum. We have carefully corrected for the nonlinearities in the mapping from real space to redshift space, according to the theoretical model of Zhang et al. Finally, we obtain the measurement of structure growth rate f(z{sub eff})σ {sub 8}(z{sub eff}) = 0.438 ± 0.037 at the effective redshift z{sub eff} = 0.57. The result is useful for constraining cosmological parameters. The measurements of the 2D power spectrum will be released soon.

79 ASTRONOMY AND ASTROPHYSICS↗