198 research outputs found

    Cosmological Beliefs About Origins Related to Science Achievement Among Junior High-School Students in South Bend, Indiana

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    Problem. American high-school students score lower in science achievement tests than their peers in other developed nations. The Organization for Economic Cooperation and Development (OECD) ranked the scientific achievement of American high-school students as ā€•very lowā€– in comparison to high-school students in other industrialized nationsā€”only 29th out of 57 developed countries. Research has indicated that achievement declines as U.S. students progress to higher grades and take on more rigorous science courses. A variety of factors have been documented that may account for U.S. studentsā€˜ lower science achievement rankings. These include socioeconomic status, race, and gender. One area only marginally explored is the role of cosmological beliefsā€”such as New Earth Creationismā€”on science achievement. Some studies indicate that these cosmological beliefs correlate to low science achievement, while others show little to no correlation between cosmological beliefs and science achievement. Americans are unique in their high rate of belief in divine special creation, as opposed to origin by evolution through natural selection. This cosmological view of origins differs from mainstream scientific thought, research, and publications. Some wonder whether this view of creation might partially explain the lower science achievement reported in American students. This problem needs to be more thoroughly investigated. Research on cosmological beliefs has focused mostly on college students in biology courses, but this study sought to understand this problem at the junior-high level of science education. Research Design. A quasi-experimental design was used. The entire study took place at Clay Intermediate Center, a public school within the South Bend Community School Corporation (SBCSC) in South Bend, Indiana. A treatment group of 47 middle-school students participated in a three-session after-school science program. Their science achievement within the program was compared to their cosmological beliefs and other socio-demographic and instructional variables. Posttests were used to measure studentsā€˜ science achievement. The pretest and posttest were constructed using a test bank available from the publisher of the science unit. A control group of similar students took the pretest and posttest but did not participate in the after-school sessions. The studentsā€˜ level of science achievement from the posttest scores were then compared to their responses to statements from Eugenie Scottā€˜s Spectrum of Creationism scale, which measures cosmological beliefs related to origins (creationism to natural evolution). The quantitative data were represented in structural equation model(s). Students were debriefed with questions regarding their feelings of how their cosmological beliefs might affect their science achievement both within the course and in general. Results. The study found no significance between science achievement and cosmological beliefs, but very strong multiple correlations of socioeconomic status and previous science knowledge to science achievement, as well as evidence that the instruction was effective in raising posttest scores. Recommendations were made that: (a) The significance of poverty status to science achievement of SBCSC students be further studied, (b) the study be extended to other middle schools and high schools within SBCSC, (c) SBCSC recognize the efficacy of after-school programs and consider further funding for these programs, and (d) SBCSC consider a unit that emphasizes empirical evidence, how things evolve, and the process of science through guided inquiry upon its next science adoption

    Results From the Periodontitis and Vascular Events (PAVE) Study: A Pilot Multicentered, Randomized, Controlled Trial to Study Effects of Periodontal Therapy in a Secondary Prevention Model of Cardiovascular Disease

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    Background- In the Periodontitis and Vascular Events (PAVE) pilot study, periodontal therapy was provided as an intervention in a secondary cardiac event prevention model through five coordinated cardiac-dental centers. Methods- Subjects were randomized to either community care or protocol provided scaling and root planing to evaluate effects on periodontal status and systemic levels of high-sensitivity Creactive protein (hs-CRP). Results- After 6 months, there was a significant reduction in mean probing depth and extent of 4- or 5-mm pockets. However, there were no significant differences in attachment levels, bleeding upon probing, or extent of subgingival calculus comparing subjects assigned to protocol therapy (n = 151) to those assigned to community care (n = 152). Using intent-to-treat analyses, there was no significant effect on serum hs-CRP levels at 6 months. However, 48% of the subjects randomized to community care received preventive or periodontal treatments. Secondary analyses demonstrated that consideration of any preventive or periodontal care (i.e., any treatment) compared to no treatment showed a significant reduction in the percentage of people with elevated hs-CRP (values >3 mg/l)at 6 months. However, obesity nullified the periodontal treatment effects on hs-CRP reduction. The adjusted odds ratio for hs-CRP levels >3 mg/l at 6 months for any treatment versus no treatment among non-obese individuals was 0.26 (95%confidence interval: 0.09 to 0.72), adjusting for smoking, marital status, and gender. Conclusion- This pilot study demonstrated the critical role of considering obesity as well as rigorous preventive and periodontal care in trials designed to reduce cardiovascular risk. Originally published Journal of Periodontology, Vol. 80, No. 2, Feb 200

    Efficacy of Guardian Cap Soft-Shell Padding on Head Impact Kinematics in American Football: Pilot Findings

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    Sport-related concussion prevention strategies in collision sports are a primary interest for sporting organizations and policy makers. After-market soft-shell padding purports to augment the protective capabilities of standard football helmets and to reduce head impact severity. We compared head impact kinematics [peak linear acceleration (PLA) and peak rotational acceleration (PRA)] in athletes wearing Guardian Cap soft-shell padding to teammates without soft-shell padding. Ten Division I college football players were enrolled [soft-shell padding (SHELL) included four defensive linemen and one tight end; non-soft-shell (CONTROL) included two offensive linemen, two defensive linemen, and one tight end]. Participants wore helmets equipped with the Head Impact Telemetry System to quantify PLA (g) and PRA (rad/s2) during 14 practices. Two-way ANOVAs were conducted to compare log-transformed PLA and PRA between groups across helmet location and gameplay characteristics. In total, 968 video-confirmed head impacts between SHELL (n = 421) and CONTROL (n = 547) were analyzed. We observed a Group x Stance interaction for PRA (F1,963 = 7.21; p = 0.007) indicating greater PRA by SHELL during 2-point stance and lower PRA during 3- or 4-point stances compared to CONTROL. There were no between-group main effects. Protective soft-shell padding did not reduce head impact kinematic outcomes among college football athletes

    The Evolution of Travelling Waves in a KPP Reaction-Diffusion Model with Cut-off Reaction Rate. I. Permanent Form Travelling Waves

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    We consider Kolmogorov--Petrovskii--Piscounov (KPP) type models in the presence of a discontinuous cut-off in reaction rate at concentration u=ucu=u_c. In Part I we examine permanent form travelling wave solutions (a companion paper, Part II, is devoted to their evolution in the large time limit). For each fixed cut-off value 0<uc<10<u_c<1, we prove the existence of a unique permanent form travelling wave with a continuous and monotone decreasing propagation speed vāˆ—(uc)v^*(u_c). We extend previous asymptotic results in the limit of small ucu_c and present new asymptotic results in the limit of large ucu_c which are respectively obtained via the systematic use of matched and regular asymptotic expansions. The asymptotic results are confirmed against numerical results obtained for the particular case of a cut-off Fisher reaction function

    Rudimentary G-Quadruplex-Based Telomere Capping In Saccharomyces Cerevisiae

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    Telomere capping conceals chromosome ends from exonucleases and checkpoints, but the full range of capping mechanisms is not well defined. Telomeres have the potential to form G-quadruplex (G4) DNA, although evidence for telomere G4 DNA function in vivo is limited. In budding yeast, capping requires the Cdc13 protein and is lost at nonpermissive temperatures in cdc13-1 mutants. Here, we use several independent G4 DNA-stabilizing treatments to suppress cdc13-1 capping defects. These include overexpression of three different G4 DNA binding proteins, loss of the G4 DNA unwinding helicase Sgs1, or treatment with small molecule G4 DNA ligands. In vitro, we show that protein-bound G4 DNA at a 3\u27 overhang inhibits 5\u27-\u3e 3\u27 resection of a paired strand by exonuclease I. These findings demonstrate that, at least in the absence of full natural capping, G4 DNA can play a positive role at telomeres in vivo

    Aggregate risk of cardiovascular disease among adolescents perinatally infected with the human immunodeficiency virus

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    BACKGROUND: Perinatally HIV-infected adolescents may be susceptible to aggregate atherosclerotic cardiovascular disease risk, as measured by the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) coronary arteries and abdominal aorta risk scores, as a result of prolonged exposure to HIV and antiretroviral therapy. METHODS AND RESULTS: Coronary arteries and abdominal aorta PDAY scores were calculated for 165 perinatally HIV-infected adolescents, using a weighted combination of modifiable risk factors: dyslipidemia, cigarette smoking, hypertension, obesity, and hyperglycemia. Demographic and HIV-specific predictors of scores ā‰„1 were identified, and trends in scores over time were assessed. Forty-eight percent and 24% of the perinatally HIV-infected adolescents had coronary arteries and abdominal aorta scores ā‰„1, representing increased cardiovascular disease risk factor burden. Significant predictors of coronary arteries scores ā‰„1 included male sex, history of an AIDS-defining condition, longer duration of use of a ritonavir-boosted protease inhibitor, and no prior use of tenofovir. Significant predictors of abdominal aorta scores ā‰„1 included suppressed viral load, history of an AIDS-defining condition, and longer duration of boosted protease inhibitor use. No significant changes in coronary arteries and abdominal aorta risk scores were observed over the 4-year study period. CONCLUSIONS: A substantial proportion of perinatally HIV-infected youth have high PDAY scores, reflecting increased aggregate atherosclerotic cardiovascular disease risk factor burden. High scores were predicted by HIV disease severity and boosted protease inhibitor use. PDAY scores may be useful in identifying high-risk youth who may benefit from early lifestyle or clinical interventions

    Epigenetic change in e-cardherin and COX-2 to predict chronic periodontitis

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    <p>Abstract</p> <p>Background</p> <p>DNA methylation of certain genes frequently occurs in neoplastic cells. Although the cause remains unknown, many genes have been identified with such atypical methylation in neoplastic cells. The hypermethylation of E-Cadherin and Cyclooxygenase 2 (COX-2) in chronic inflammation such as chronic periodontitis may demonstrate mild lesion/mutation epigenetic level. This study compares the hypermethylation status of E-Cadherin and COX-2 genes which are often found in breast cancer patients with that in chronic periodontitis.</p> <p>Methods</p> <p>Total DNA was extracted from the blood samples of 108 systemically healthy non-periodontitis subjects, and the gingival tissues and blood samples of 110 chronic periodontitis patient as well as neoplastic tissues of 106 breast cancer patients. Methylation-specific PCR for E-Cadherin and COX-2 was performed on these samples and the PCR products were analyzed on 2% agarose gel.</p> <p>Results</p> <p>Hypermethylation of E-Cadherin and COX-2 was observed in 38% and 35% of the breast cancer samples, respectively. In chronic periodontitis patients the detection rate was 25% and 19% respectively, and none was found in the systemically healthy non-periodontitis control subjects. The hypermethylation status was shown to be correlated among the three groups with statistical significance (p < 0.0001). The methylation of CpG islands in E-Cadherin and COX-2 genes in periodontitis patients occurs more frequently in periodontitis patients than in the control subjects, but occurs less frequently than in the breast cancer patients.</p> <p>Conclusions</p> <p>This set of data shows that the epigenetic change in E-Cadherin and Cyclooxygenase-2 is associated with chronic periodontitis. The epigenetic changes presented in chronic inflammation patients might demonstrate an irreversible destruction in the tissues or organs similar to the effects of cancer. Chronic periodontitis to some extent might be associated with DNA hypermethylation which is related to cancer risk factors.</p

    Ecology of Juvenile Salmon in Shallow Tidal Freshwater Habitats of the Lower Columbia River, 2007?2010

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    The TFM study was designed to investigate the ecology and early life history of juvenile salmonids within shallow (<5 m) tidal freshwater habitats of the LCRE. We started collecting field data in June 2007. Since then, monthly sampling has occurred in the vicinity of the Sandy River delta (rkm 192ā€“208) and at other sites and times in lower river reaches of tidal freshwater (rkm 110 to 141). This report provides a comprehensive synthesis of data covering the field period from June 2007 through April 2010
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