The development of concrete operational structures as a function of structural equilibration in normal and mentally retarded populations.

Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1974 .V32. Source: Dissertation Abstracts International, Volume: 62-13, Section: A. Thesis (Ph.D.)--University of Windsor (Canada), 1974

Laboratory Testing of a Lyot Coronagraph Equipped with an Eighth-Order Notch Filter Image Mask

We have built a series of notch filter image masks that make the Lyot coronagraph less susceptible to low-spatial-frequency optical aberrations. In this paper, we present experimental results of their performance in the lab using monochromatic light. Our tests show that these ``eighth-order'' masks are resistant to tilt and focus alignment errors, and can generate contrast levels of 2 x 10^-6 at 3 lambda/D and 6 x 10^-7 at 10 lambda/D without the use of corrective optics such as deformable mirrors. This work supports recent theoretical studies suggesting that eighth-order masks can provide the Terrestrial Planet Finder Coronagraph with a large search area, high off-axis throughput, and a practical requisite pointing accuracy.Comment: Accepted to ApJ. 16 pages, 7 figures, Contact [email protected] for high resolution image

Walnut oil increases cholesterol efflux through inhibition of stearoyl CoA desaturase 1 in THP-1 macrophage-derived foam cells

Extent: 13p.Background: Walnuts significantly decrease total and low-density lipoprotein cholesterol in normo- and hypercholesterolemic individuals. No study to date has evaluated the effects of walnuts on cholesterol efflux, the initial step in reverse cholesterol transport, in macrophage-derived foam cells (MDFC). The present study was conducted to investigate the mechanisms by which walnut oil affects cholesterol efflux. Methods: The extract of English walnuts (walnut oil) was dissolved in DMSO and applied to cultured THP-1 MDFC cells (0.5 mg/mL). THP-1 MDFC also were treated with human sera (10%, v:v) taken from subjects in a walnut feeding study. Cholesterol efflux was examined by liquid scintillation counting. Changes in gene expression were quantified by real time PCR. Results: Walnut oil treatment significantly increased cholesterol efflux through decreasing the expression of the lipogenic enzyme stearoyl CoA desaturase 1 (SCD1) in MDFC. Alpha-linolenic acid (ALA), the major n-3 polyunsaturated fatty acids found in walnuts, recaptured SCD1 reduction in MDFC, a mechanism mediated through activation of nuclear receptor farnesoid-X-receptor (FXR). Postprandial serum treatment also increased cholesterol efflux in MDFC. When categorized by baseline C-reactive protein (CRP; cut point of 2 mg/L), subjects in the lower CRP sub-group benefited more from dietary intervention, including a more increase in cholesterol efflux, a greater reduction in SCD1, and a blunted postprandial lipemia. Conclusion: In conclusion, walnut oil contains bioactive molecules that significantly improve cholesterol efflux in MDFC. However, the beneficial effects of walnut intake may be reduced by the presence of a pro-inflammatory state.Jun Zhang, Jessica A Grieger, Penny M Kris-Etherton, Jerry T Thompson, Peter J Gillies, Jennifer A Fleming and John P Vanden Heuve

Precursors to potential severe core damage accidents: 1994, a status report. Volume 22: Appendix I

Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 {times} 10{sup {minus}6}. These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1

Precursors to potential severe core damage accidents: 1994, a status report. Volume 21: Main report and appendices A--H

Nine operational events that affected eleven commercial light-water reactors (LWRs) during 1994 and that are considered to be precursors to potential severe core damage are described. All these events had conditional probabilities of subsequent severe core damage greater than or equal to 1.0 {times} 10{sup {minus}6}. These events were identified by computer-screening the 1994 licensee event reports from commercial LWRs to identify those that could be potential precursors. Candidate precursors were then selected and evaluated in a process similar to that used in previous assessments. Selected events underwent engineering evaluation that identified, analyzed, and documented the precursors. Other events designated by the Nuclear Regulatory Commission (NRC) also underwent a similar evaluation. Finally, documented precursors were submitted for review by licensees and NRC headquarters and regional offices to ensure that the plant design and its response to the precursor were correctly characterized. This study is a continuation of earlier work, which evaluated 1969--1981 and 1984--1993 events. The report discusses the general rationale for this study, the selection and documentation of events as precursors, and the estimation of conditional probabilities of subsequent severe core damage for events. This document is bound in two volumes: Vol. 21 contains the main report and Appendices A--H; Vol. 22 contains Appendix 1

The First Extrasolar Planet Discovered with a New Generation High Throughput Doppler Instrument

We report the detection of the first extrasolar planet, ET-1 (HD 102195b), using the Exoplanet Tracker (ET), a new generation Doppler instrument. The planet orbits HD 102195, a young star with solar metallicity that may be part of the local association. The planet imparts radial velocity variability to the star with a semiamplitude of $63.4\pm2.0$ m s$^{-1}$ and a period of 4.11 days. The planetary minimum mass ($m \sin i$) is $0.488\pm0.015$ $M_J$.Comment: 42 pages, 11 figures and 5 tables, Accepted for publication in Ap

CDK-Mediated Regulation of Cell Functions via c-Jun Phosphorylation and AP-1 Activation

Cyclin-dependent kinases (CDKs) and their targets have been primarily associated with regulation of cell-cycle progression. Here we identify c-Jun, a transcription factor involved in the regulation of a broad spectrum of cellular functions, as a newly recognized CDK substrate. Using immune cells from mouse and human, and several complementary in vitro and in vivo approaches including dominant negative protein expression, pharmacologic inhibitors, kinase assays and CDK4 deficient cells, we demonstrate the ability of CDK4 to phosphorylate c-Jun. Additionally, the activity of AP-1, a ubiquitous transcription factor containing phosphorylated c-Jun as a subunit, was inhibited by abrogating CDK4. Surprisingly, the regulation of c-Jun phosphorylation by CDK4 occurred in non-dividing cells, indicating that this pathway is utilized for cell functions that are independent of proliferation. Our studies identify a new substrate for CDK4 and suggest a mechanism by which CDKs can regulate multiple cellular activation functions, not all of which are directly associated with cell cycle progression. These findings point to additional roles of CDKs in cell signaling and reveal potential implications for therapeutic manipulations of this kinase pathway

Profiling of promoter occupancy by PPARα in human hepatoma cells via ChIP-chip analysis

The transcription factor peroxisome proliferator-activated receptor α (PPARα) is an important regulator of hepatic lipid metabolism. While PPARα is known to activate transcription of numerous genes, no comprehensive picture of PPARα binding to endogenous genes has yet been reported. To fill this gap, we performed Chromatin immunoprecipitation (ChIP)-chip in combination with transcriptional profiling on HepG2 human hepatoma cells treated with the PPARα agonist GW7647. We found that GW7647 increased PPARα binding to 4220 binding regions. GW7647-induced binding regions showed a bias around the transcription start site and most contained a predicted PPAR binding motif. Several genes known to be regulated by PPARα, such as ACOX1, SULT2A1, ACADL, CD36, IGFBP1 and G0S2, showed GW7647-induced PPARα binding to their promoter. A GW7647-induced PPARα-binding region was also assigned to SREBP-targets HMGCS1, HMGCR, FDFT1, SC4MOL, and LPIN1, expression of which was induced by GW7647, suggesting cross-talk between PPARα and SREBP signaling. Our data furthermore demonstrate interaction between PPARα and STAT transcription factors in PPARα-mediated transcriptional repression, and suggest interaction between PPARα and TBP, and PPARα and C/EBPα in PPARα-mediated transcriptional activation. Overall, our analysis leads to important new insights into the mechanisms and impact of transcriptional regulation by PPARα in human liver and highlight the importance of cross-talk with other transcription factors