North Carolina State University

About: North Carolina State University is a education organization based out in Raleigh, North Carolina, United States. It is known for research contribution in the topics: Population & Thin film. The organization has 44161 authors who have published 101744 publications receiving 3456774 citations. The organization is also known as: NCSU & North Carolina State University at Raleigh.

Repeated polyploidization of Gossypium genomes and the evolution of spinnable cotton fibres

Abstract: Polyploidy often confers emergent properties, such as the higher fibre productivity and quality of tetraploid cottons than diploid cottons bred for the same environments. Here we show that an abrupt five- to sixfold ploidy increase approximately 60 million years (Myr) ago, and allopolyploidy reuniting divergent Gossypium genomes approximately 1-2 Myr ago, conferred about 30-36-fold duplication of ancestral angiosperm (flowering plant) genes in elite cottons (Gossypium hirsutum and Gossypium barbadense), genetic complexity equalled only by Brassica among sequenced angiosperms. Nascent fibre evolution, before allopolyploidy, is elucidated by comparison of spinnable-fibred Gossypium herbaceum A and non-spinnable Gossypium longicalyx F genomes to one another and the outgroup D genome of non-spinnable Gossypium raimondii. The sequence of a G. hirsutum A(t)D(t) (in which 't' indicates tetraploid) cultivar reveals many non-reciprocal DNA exchanges between subgenomes that may have contributed to phenotypic innovation and/or other emergent properties such as ecological adaptation by polyploids. Most DNA-level novelty in G. hirsutum recombines alleles from the D-genome progenitor native to its New World habitat and the Old World A-genome progenitor in which spinnable fibre evolved. Coordinated expression changes in proximal groups of functionally distinct genes, including a nuclear mitochondrial DNA block, may account for clusters of cotton-fibre quantitative trait loci affecting diverse traits. Opportunities abound for dissecting emergent properties of other polyploids, particularly angiosperms, by comparison to diploid progenitors and outgroups.

“So When It Comes Out, They Aren’t That Surprised That It Is There”: Using Critical Race Theory as a Tool of Analysis of Race and Racism in Education

Abstract: J asmine,' an African-American 9thexamining the educational experiences of cluding areas that can be considered upper grade student, described the racial and African-American students. Critical Race class, middle class, and less affluent areas. cultural climate at Wells Academy, an Theory (CRT) is a useful perspective from Most of the African American students, elite, predominately White, independent which to explore such phenomena. In this however, are considered middle class.2 school. She stated, "Everybody knows that article, we will illustrate how CRT can be Two such African-American students racism exists and that people are racist. So used to examine the experiences of were Malcolm and Barbara. Malcolm was when it comes out, they [faculty and stuAfrican-American students. We will use a 17-year-old senior from a middle-class dents] aren't that surprised that it is there." the counterstories of African-American family. He was very active in school leadAs Jasmine asserted, racism is prevalent in students at Wells Academy, an elite, preership activities and was an athlete. Barall aspects of society, with schools not dominately White, independent school. bara was an 18-year-old recent graduate being an exception. However, what is Wells Academy from a prominent, upper-class family. She most interesting about her statement is was also very active in school leadership thatWells Academy is located in a major city activities. Both students were very proud monplace within the school walls that in an affluent, predominately White area of their African-American heritage and monplace within the school walls that in the southeastern United States. Propoften participated in the African-Ameriwhen it appears, e erty values in this community range from can cultural activities at Wells. has already begun to understand the per$450,000 to over $3 million. Wells has Because of Malcolm's and Barbara's

Genetic properties of the maize nested association mapping population.

Abstract: Maize genetic diversity has been used to understand the molecular basis of phenotypic variation and to improve agricultural efficiency and sustainability. We crossed 25 diverse inbred maize lines to the B73 reference line, capturing a total of 136,000 recombination events. Variation for recombination frequencies was observed among families, influenced by local (cis) genetic variation. We identified evidence for numerous minor single-locus effects but little two-locus linkage disequilibrium or segregation distortion, which indicated a limited role for genes with large effects and epistatic interactions on fitness. We observed excess residual heterozygosity in pericentromeric regions, which suggested that selection in inbred lines has been less efficient in these regions because of reduced recombination frequency. This implies that pericentromeric regions may contribute disproportionally to heterosis.

Inhibitors of ethylene responses in plants at the receptor level: Recent developments

Abstract: A number of organic molecules that appear to block the ethylene receptor have been discovered recently. For example, on irradiation with visible light, diazocyclopentadiene (DACP), gives rise to some potent but as yet unidentified inhibitor compounds. Some synthetic cyclopropenes have been shown to bind to the ethylene receptor and prevent the physiological action of ethylene for extended periods. Cyclopropene (CP), 1-methylcyclopropene (1-MCP) and 3,3-dimethylcyclopropene (3,3-DMCP) have been shown to prevent ethylene effects in a number of plants. As low a concentration as 0.5 nl l -1 of 1-MCP is sufficient to protect carnation (Dianthus caryophyllus) flowers for several days against ethylene, and 0.7 nl l -1 1-MCP or CP will prevent the ripening of banana (Musa sapientum) for 12 days at 24°C. Some plant organs require higher concentrations of these inhibitors. Complete inhibition of ethylene effects in pea seedlings requires treatment with 40 nl 1 -1 of 1-MCP. These novel inhibitors appear to be suitable for many commercial applications including extending the vase life of cut flowers and the display life of potted plants. Since 1-MCP apparently is non-toxic at concentrations that are active, it may in future be available for regulating the ripening of fruits and preventing the deleterious effects of ethylene in vegetables.