Genetic dissection of grain iron concentration in hexaploid wheat (Triticum aestivum L.) using a genome-wide association analysis method

Iron (Fe) is an essential micronutrient of the body. Low concentrations of bioavailable Fe in staple food result in micronutrient malnutrition. Wheat (Triticum aestivum L.) is the most important global food crop and thus has become an important source of iron for people. Breeding nutritious wheat with high grain-Fe content has become an effective means of alleviating malnutrition. Understanding the genetic basis of micronutrient concentration in wheat grains may provide useful information for breeding for high Fe varieties through marker-assisted selection (MAS). Hence, in the present study, genome-wide association studies (GWAS) were conducted for grain Fe. An association panel of 207 accessions was genotyped using a 660K SNP array and phenotyped for grain Fe content at three locations. The genotypic and phenotypic data obtained thus were used for GWAS. A total of 911 SNPs were significantly associated with grain Fe concentrations. These SNPs were distributed on all 21 wheat chromosomes, and each SNP explained 5.79–25.31% of the phenotypic variations. Notably, the two significant SNPs (AX-108912427 and AX-94729264) not only have a more significant effect on grain Fe concentration but also have the reliability under the different environments. Furthermore, candidate genes potentially associated with grain Fe concentration were predicted, and 10 candidate genes were identified. These candidate genes were related to transport, translocation, remobilization, and accumulationof ironin wheat plants. These findings will not only help in better understanding the molecular basis of Fe accumulation in grains, but also provide elite wheat germplasms to develop Fe-rich wheat varieties through breeding

A new FACS approach isolates hESC derived endoderm using transcription factors.

We show that high quality microarray gene expression profiles can be obtained following FACS sorting of cells using combinations of transcription factors. We use this transcription factor FACS (tfFACS) methodology to perform a genomic analysis of hESC-derived endodermal lineages marked by combinations of SOX17, GATA4, and CXCR4, and find that triple positive cells have a much stronger definitive endoderm signature than other combinations of these markers. Additionally, SOX17(+) GATA4(+) cells can be obtained at a much earlier stage of differentiation, prior to expression of CXCR4(+) cells, providing an important new tool to isolate this earlier definitive endoderm subtype. Overall, tfFACS represents an advancement in FACS technology which broadly crosses multiple disciplines, most notably in regenerative medicine to redefine cellular populations

Improved Pedestrian Dead Reckoning Based on a Robust Adaptive Kalman Filter for Indoor Inertial Location System

Pedestrian dead reckoning (PDR) systems based on a microelectromechanical-inertial measurement unit (MEMS-IMU) providing advantages of full autonomy and strong anti-jamming performance are becoming a feasible choice for pedestrian indoor positioning. In order to realize the accurate positioning of pedestrians in a closed environment, an improved pedestrian dead reckoning algorithm, mainly including improved step estimation and heading estimation, is proposed in this paper. Firstly, the original signal is preprocessed using the wavelet denoising algorithm. Then, the multi-threshold method is proposed to ameliorate the step estimation algorithm. For heading estimation suffering from accumulated error and outliers, robust adaptive Kalman filter (RAKF) algorithm is proposed in this paper, and combined with complementary filter to improve positioning accuracy. Finally, an experimental platform with inertial sensors as the core is constructed. Experimental results show that positioning error is less than 2.5% of the total distance, which is ideal for accurate positioning of pedestrians in enclosed environment

Inhibiting the Corrosion-Promotion Activity of Graphene

Though an excellent protection material, graphene possesses an unpleasant adverse side effect, which refers to the phenomenon that graphene can aggravate metal corrosion. This effect potentially impedes its applications in metal protection. This work aims to demonstrate a facile graphene encapsulation strategy to effectively inhibit the corrosion-promotion activity of graphene. We encapsulated reduced graphene oxide (rGO) with (3-aminopropyl)­triethoxysilane (APTES). The composite of encapsulated rGO (rGO@APTES) has a flake-like structure with high aspect-ratio. Embedding appropriate amounts of rGO@APTES in polyvinyl butyral coating effectively enhances the barrier properties of the coating by suppressing the penetration of aggressive species. Besides, scratch tests further reveal that the corrosion-promotion activity of the graphene incorporated into the coating is completely inhibited. The strategy of graphene encapsulation can be extended to develop new graphene-based materials with superior physical and chemical properties for the protection of metal components

Understanding the Morphology of High-Performance Solar Cells Based on a Low-Cost Polymer Donor

results show that the degree of phase separation and ordering in the PTQ10-based devicesA low-cost and high-performance bulk heterojunction (BHJ) solar cell comprising an emerging polymer donor, poly[(thiophene)-alt-(6,7-difluoro-2-(2-hexyldecyloxy)quinoxaline)] (PTQ10), shows an efficiency of 12.7%. To improve the performance of the solar cells, a better understanding of the structure-property relationships of the PTQ10-based devices is crucial. Here, we fabricate PTQ10/nonfullerene and fullerene BHJ devices, including PTQ10/IDIC, PTQ10/ITIC, and PTQ10/PC71BM, processed with or without thermal annealing and additive and provide detailed descriptions of the relationships between the morphology and performance. PTQ10 is found to be highly miscible with nonfullerene IDIC and ITIC acceptors and poorly miscible with fullerene PC71BM acceptors. Thermal annealing promotes the crystallization of PTQ10 and phase separation of all PTQ10/IDIC, PTQ10/ITIC, and PTQ10/PC71BM devices, leading to an increased power conversion efficiencies (PCEs) of the PTQ10/IDIC and PTQ10/ITIC devices but a decreased PCE of PTQ10/PC71BM devices additive. Without thermal annealing, DIO greatly improves the morphology of PTQ10/PC71BM, leading to a higher PCE. The results show that the degree of phase separation and ordering in the PTQ10-based devices significantly influences device performance. The morphology-property correlations demonstrated will assist in the rational design of these low-cost polymer donor-based solar cells to achieve even higher performance

Starch Bio-Synthetic Pathway Genes Contribute to Resistant Starch Content Differentiation in Bread Wheat

Resistant starch (RS) is a special group of starches which are slowly degraded and rarely digested in the gastrointestinal tract. It was recognized as a new type of dietary fiber that improved cardiovascular, cerebrovascular, and intestinal health. Breeding high-RS-content wheat is one of the most efficient and convenient approaches for providing an adequate amount of RS for a healthy diet. However, studies which aim to genetically illustrate RS content in wheat are still rare. In the present study, a panel of 207 wheat varieties were collected world-wide and planted under three locations. The RS content of each variety was measured, and 14 additive genetic loci were found to stably exist under more than two environments. Meanwhile, four genes were recognized as the putative candidates with annotated functions of β-amylase, α-1,4 glucan phosphorylase, sucrose transporter, and NAC domain protein. A kompetitive allele-specific PCR (KASP) marker was developed from the SNP AX-94546744, representing the genetic locus of β-amylase located. The AX-94546744-T allele can significantly increase the RS content compared to the AX-94546744-C allele. The genetic loci and KASP marker associated with RS content may be useful for wheat germplasm cultivation and variety breeding with a high RS content, further helping to improve the nutritional quality in wheat