Exposure to Electronic Entertainment Media and Student Outcomes in Two Demographically Diverse Elementary Schools

Problem. Standardized test-score results have declined sharply and learning difficulties have risen significantly during the decades that electronic entertainment media (EEM) have become a national phenomenon. Exposure to electronic entertainment media has generated much speculation, discussion, and study. Research, however, is lacking on how sensory overload impinges upon the brain and mind of developing children with respect to learning and adapting socially. Thus, research is needed that addresses sensory overload phenomena and academic performance and social behavior. Methodology. The population consisted of 349 third- and fourth-grade children in a demographically diverse public school district located in southwestern Michigan. The Time Tally Checklist, a Likert-type questionnaire that was developed for third- and fourth-grade children, furnished data in six categories of activity. Frequencies, crosstabulations, Pearson product-moment correlation coefficient, Spearman correlation coefficient, and the Chi-square test for Homogeneity were used to test the hypotheses. A correlational research design was used to determine the extent to which time spent exposed to EEM corresponds to academic performance, discretionary academic activities, and social/recreational activity. Results. With reference to hypothesis 1 (To what extent does exposure to EEM correlate with formal academic performance?), 7 out of 64 pairings were significantly correlated--2 positive and 5 negative. So far as these data indicate, there appears to be little relationship between amount of EEM exposure and formal academic performance. With reference to hypothesis 2 (To what extent does exposure to EEM correlate with discretionary activity?), only 13 out of 132 pairings, were significantly correlated; there appears to be little relationship between amount of EEM exposure and discretionary academic activity. With reference to hypothesis 3 (To what extent does exposure to EEM correlate with recreational and social behavior?), 122 out of 270 pairings were significantly correlated; there appears to be a fair relationship between amount of EEM exposure and social behavior. Conclusions. Exposure to EEM may be related to academic achievement of third- and fourth-grade students. However, relatively little evidence for it is found in this study. Limitations of this study considered with other studies and commentary suggest that a more definitive examination of EEM and its relationship with the developing child is warranted. Exposure to EEM may be related to student initiated activities such as reading for personal fulfillment, homework, and noise preference. However, the evidence in this study is inconclusive across the two grade levels examined. Exposure to EEM is related in complex ways to social behavior such as play, talk, hobbies, and discipline. When viewed with the other data in this study, the research indicates a drift away from traditional social attitudes such as talking and hobbies toward more media-oriented culture as students move through the grades

Lessons learned from 32 years of retained ownership – TCSCF summary

Tri-County Steer Carcass Futurity (TCSCF) was started by Pottawattamie, Cass and Shelby County Cattleman’s Association in 1982. The nine member board wanted to know “what was the most profitable steer to feed?” In 2002, the SW Iowa cowcalf consigners utilizing the TCSCF program formed a service cooperative. The current 10 member board has 7 cow-calf producers, two allied industry representatives and one veterinarian

Construction Cost Sensitivity of a Lignocellulosic Ethanol Biorefinery

The technology has been developed to convert feedstock with cellulose content into ethanol. However, ethanol produced from cellulosic feedstock is the same as ethanol distilled from grain. The objective of research is to determine the price per gallon of ethanol needed so that producing lignocellulosic based ethanol become economically feasible.Environmental Economics and Policy, Production Economics,

Activation of σ28-dependent transcription inEscherichia coliby the cyclic AMP receptor protein requires an unusual promoter organization

The Escherichia coli aer regulatory region contains a single promoter that is recognized by RNA polymerase containing the flagellar sigma factor, σ28. Expression from this promoter is dependent on direct activation by the cyclic AMP receptor protein, which binds to a target centred 49.5 base pairs upstream from the transcript start. Activator-dependent transcription from the aer promoter was reconstituted in vitro, and a tethered inorganic nuclease was used to find the position of the C-terminal domains of the RNA polymerase α subunits in transcriptionally competent open complexes. We report that the ternary activator-RNA polymerase-aer promoter open complex is organized differently from complexes at previously characterized promoters. Among other E. coli promoters recognized by RNA polymerase containing σ28, only the trg promoter is activated directly by the cyclic AMP receptor protein. The organization of the different promoter elements and the activator binding site at the trg promoter is the same as at the aer promoter, suggesting a common activation mechanism

Computation of steady and unsteady quasi-one-dimensional viscous/inviscid interacting internal flows at subsonic, transonic, and supersonic Mach numbers

Computations of viscous-inviscid interacting internal flowfields are presented for steady and unsteady quasi-one-dimensional (Q1D) test cases. The unsteady Q1D Euler equations are coupled with integral boundary-layer equations for unsteady, two-dimensional (planar or axisymmetric), turbulent flow over impermeable, adiabatic walls. The coupling methodology differs from that used in most techniques reported previously in that the above mentioned equation sets are written as a complete system and solved simultaneously; that is, the coupling is carried out directly through the equations as opposed to coupling the solutions of the different equation sets. Solutions to the coupled system of equations are obtained using both explicit and implicit numerical schemes for steady subsonic, steady transonic, and both steady and unsteady supersonic internal flowfields. Computed solutions are compared with measurements as well as Navier-Stokes and inverse boundary-layer methods. An analysis of the eigenvalues of the coefficient matrix associated with the quasi-linear form of the coupled system of equations indicates the presence of complex eigenvalues for certain flow conditions. It is concluded that although reasonable solutions can be obtained numerically, these complex eigenvalues contribute to the overall difficulty in obtaining numerical solutions to the coupled system of equations

A Seven Year Summary of Feeding Cull Market Cows

Nine groups totaling 457 culled market cows were fed high concentrate rations at two locations in SW Iowa to demonstrate the possibilities of finishing for the “White Fat Cow” market. Average profit per head was $16.54 with a range$174.36 to -$91.45. Adjusted final weights ranged from 1484 to 1646 pounds, while average daily gains ranged from 2.88 to 4.55 pounds daily during a 70 to 91 day feeding program. Dry matter feed conversions on a shrunk basis ranged from 8.70 to 12.78 pounds per pound of gain with an average of 10.91. From 78.4 to 98.8 percent of the cows within the fed groups qualified in the “Premium White Fat” grades with an average of 85.5$98.03 with a range of $70.81 to$156.85. Delivery weight had a significant impact on average daily gain, feed cost of gain and total cost of gain; however body condition score had no significant impact on performance traits or cost of gain

Does Carcass Value Gain per Day on Feed Used in the 4-H Program Relate to Cattle Feeding Profitability?

Data from 410 feedout groups representing 29,389 head from the Tri-County Steer Carcass Futurity Cooperative were analyzed to test the validity of using carcass value per day on feed (CVDOF) as a ranking tool in 4-H beef performance carcass contests. All feedout groups were calculated for feedlot profit using standardized feed and yardage costs, yet using their actual health treatment costs and miscellaneous costs. CVDOF is calculated using carcass weight gain per day during the feeding period and adjusting that for red meat yield using the percent retail product equation. This result is then put on a monetary basis by using a carcass price adjusted for carcass quality and yield grade. CVDOF when tested for its relationship to feedlot profitability was highly significant and accounted for 74 percent of the variation in profit. If one desires a ranking equation in the 4-H beef performance carcass program that relates well to feedlot profitability then CVDOF proves to be quite effective

Gene doctoring: a method for recombineering in laboratory and pathogenic Escherichia coli strains

Background: Homologous recombination mediated by the lambda-Red genes is a common method for making chromosomal modifications in Escherichia coli. Several protocols have been developed that differ in the mechanisms by which DNA, carrying regions homologous to the chromosome, are delivered into the cell. A common technique is to electroporate linear DNA fragments into cells. Alternatively, DNA fragments are generated in vivo by digestion of a donor plasmid with a nuclease that does not cleave the host genome. In both cases the lambda-Red gene products recombine homologous regions carried on the linear DNA fragments with the chromosome. We have successfully used both techniques to generate chromosomal mutations in E. coli K-12 strains. However, we have had limited success with these lambda-Red based recombination techniques in pathogenic E. coli strains, which has led us to develop an enhanced protocol for recombineering in such strains. \ud \ud Results: Our goal was to develop a high-throughput recombineering system, primarily for the coupling of genes to epitope tags, which could also be used for deletion of genes in both pathogenic and K-12 E. coli strains. To that end we have designed a series of donor plasmids for use with the lambda-Red recombination system, which when cleaved in vivo by the I-SceI meganuclease generate a discrete linear DNA fragment, allowing for C-terminal tagging of chromosomal genes with a 6xHis, 3xFLAG, 4xProteinA or GFP tag or for the deletion of chromosomal regions. We have enhanced existing protocols and technologies by inclusion of a cassette conferring kanamycin resistance and, crucially, by including the sacB gene on the donor plasmid, so that all but true recombinants are counter-selected on kanamycin and sucrose containing media, thus eliminating the need for extensive screening. This method has the added advantage of limiting the exposure of cells to the potential damaging effects of the lambda-Red system, which can lead to unwanted secondary alterations to the chromosome. \ud \ud Conclusion: We have developed a counter-selective recombineering technique for epitope tagging or for deleting genes in E. coli. We have demonstrated the versatility of the technique by modifying the chromosome of the enterohaemorrhagic O157:H7 (EHEC), uropathogenic CFT073 (UPEC), enteroaggregative O42 (EAEC) and enterotoxigenic H10407 (ETEC) E. coli strains as well as in K-12 laboratory strains