Academic Achievement Differences by Student Mobility: An Analysis of Texas Grade 8 Student Performance

Differences in reading mathematics and science achievement of Grade 8 students as a function of mobility were examined with and without controls for economic status in this investigation Data were obtained from the Texas Education Agency Public Education Information Management System for the 2003-2004 through the 2007-2008 school years Statistically significant differences were revealed in reading mathematics and science test scores as a function of student mobility both when controlling for and not controlling for economic status Mobile students had statistically significantly lower reading and mathematics test scores than did non-mobile students for all 6 school years Science scores were statistically significantly lower for all three years for which data were available Implications for policy and practice and suggestions for future research were mad

Plasma Physics

Contains reports on six research projects.United States Atomic Energy Commission (Contract AT(30-1)-1842

Plasma Physics

Contains research objectives and reports on three research projects.United States Atomic Energy Commission AT(30-1)-1842

Inheritance of enzymes and blood proteins in the leopard frog, Rana pipiens : Three linkage groups established

Individuals from natural populations of the leopard frog, Rana pipiens , were analyzed for electrophoretic differences in blood proteins and enzymes from an amputated digit. The proteins examined represent products of 72 loci. Presumptive heterozygotes at multiple loci were selected for experimental crosses. Mendelian inheritance of 18 protein variations were demonstrated in the offspring. Tests for linkage or independent assortment were performed for 75 locus pairs. Three linkage groups were established. Linkage group 1 contains two loci, aconitase-1 (Acon1) and serum albumin (Alb) , with a 19% recombination frequency between them. Linkage group 2 contains four loci, glyoxalase (Gly) , acid phosphatase-1 (Ap1) , acid phosphatase-2 (AP2) , and esterase-5 (Est5) . The data show the relationships Gly -21.1%- AP1 -0%- AP2 -6.3%- Est5 , and Gly -25.6%- Est5 . Linkage group 3 consists of four closely linked esterase loci. The data, Est1 -5.1%- Est6, Est6 -1.8%- Est10 -1.9%- Est4 and Est6 -3.0%- Est4 , do not establish a complete order but suggest that Est10 is between Est4 and Est6 . These results, with data demonstrating apparent independent assortment of 67 other locus pairs, provide a foundation for establishing the frog genetic map.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44135/1/10528_2004_Article_BF00484404.pd

The Roles of Telomerase in the Generation of Polyploidy during Neoplastic Cell Growth

AbstractPolyploidy contributes to extensive intratumor genomic heterogeneity that characterizes advanced malignancies and is thought to limit the efficiency of current cancer therapies. It has been shown that telomere deprotection in p53-deficient mouse embryonic fibroblasts leads to high rates of polyploidization. We now show that tumor genome evolution through whole-genome duplication occurs in ∼15% of the karyotyped human neoplasms and correlates with disease progression. In a panel of human cancer and transformed cell lines representing the two known types of genomic instability (chromosomal and microsatellite), as well as the two known pathways of telomere maintenance in cancer (telomerase activity and alternative lengthening of telomeres), telomere dysfunction-driven polyploidization occurred independently of the mutational status of p53. Depending on the preexisting context of telomere maintenance, telomerase activity and its major components, human telomerase reverse transcriptase (hTERT) and human telomerase RNA component (hTERC), exert both reverse transcriptase-related (canonical) and noncanonical functions to affect tumor genome evolution through suppression or induction of polyploidization. These new findings provide a more complete mechanistic understanding of cancer progression that may, in the future, lead to novel therapeutic interventions