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In this study, polypropylene/ethylene-octene copolymer (PP/POE) blends, PP/talc, and PP/POE/micro-talc (MT) composites were fabricated using a twin screw. To estimate the performances of the PP/POE blends, PP/talc, and PP/POE/MT composites, mechanical properties, heat deflection temperature (HDT), thermomechanical analysis, and isothermal crystallization characterization were conducted. Incorporating talc particles increased the tensile strength, flexural properties, and HDT of the PP matrix, but reduced the elongation at break and notched impact strength. The inclusion of POE elastomers in the PP matrix yielded the opposite effect on PP/talc composites. PP/POE/MT composites provide a compromise that improves both the flexural properties and notched impact strength. Moreover, the inclusion of talc particles in PP/POE blends induced heterogeneous nucleation and considerably reduced the crystallization time. Consequently, the time required for processing was also greatly reduced. POLYM. COMPOS.,

Seed coat color is determined by the type of pigment deposited in the seed coat cells. It is related to important agronomic traits of seeds such as seed dormancy, longevity, oil content, protein content and fiber content. In Brassica napus, inheritance of seed coat color is related to maternal effects and pollen effects (xenia effects). In this research we isolated a mutation of yellow seeded B. napus controlled by a single Mendelian locus, which is named Embryonal Control of Yellow seed coat 1 (Ecy1). Microscopy of transverse sections of the mature seed show that pigment is deposited only in the outer layer of the seed coat. Using Illumina Hisequation 2000 sequencing technology, a total of 12 GB clean data, 116× coverage of coding sequences of B. napus, was achieved from seeds 26 d after pollination (DAP). It was assembled into 172,238 independent transcripts, and 55,637 unigenes. A total of 139 orthologous genes of Arabidopsis transparent testa (TT) genes were mapped in silico to 19 chromosomes of B. napus. Only 49 of the TT orthologous genes are transcribed in seeds. However transcription of all orthologs was independent of embryonal control of seed coat color. Only 55 genes were found to be differentially expressed between brown seeds and the yellow mutant. Of these 55, 50 were upregulated and five were downregulated in yellow seeds as compared to their brown counterparts. By KEGG classification, 14 metabolic pathways were significantly enriched. Of these, five pathways: phenylpropanoid biosynthesis, cyanoamino acid metabolism, plant hormone signal transduction, metabolic pathways, and biosynthesis of secondary metabolites, were related with seed coat pigmentation. Free amino acid quantification showed that Ala and Phe were present at higher levels in the embryos of yellow seeds as compared to those of brown seeds. This increase was not observed in the seed coat. Moreover, the excess amount of free Ala was exactly twice that of Phe in the embryo. The pigment substrate chalcone is synthesized from two molecules of Ala and one molecule of Phe. The correlation between accumulation of Ala and Phe, and disappearance of pigment in the yellow seeded mutant, suggests that embryonal control of seed coat color is related with Phe and Ala metabolism in the embryo of B. napus.

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