MS-057: The Papers of Donna O. Schaper, Class of 1969: The Gettysburg Years

This collection consists of correspondence and college papers from Donna Osterhoudt Schaper, who graduated from Gettysburg College in 1969. As a student, she was part of the student protest movement against the Vietnam War, and she interned for the College Chapel before attending the Lutheran Theological Seminary. Special Collections and College Archives Finding Aids are discovery tools used to describe and provide access to our holdings. Finding aids include historical and biographical information about each collection in addition to inventories of their content. More information about our collections can be found on our website http://www.gettysburg.edu/special_collections/collections/.https://cupola.gettysburg.edu/findingaidsall/1052/thumbnail.jp

AJAE Appendix: Optimal Investment in Transportation Infrastructure When Middlemen Have Market Power: A Developing-Country Analysis

The material contained herein is supplementary to the article named in the title and published in the American Journal of Agricultural Economics.Public Economics,

Making the exotic familiar: Representing Chinese Culture in Chicago\u27s Chinatown

Changes in Chinese American culture in Chicago\u27s Chinatow

Telomeres in ICF syndrome cells are vulnerable to DNA damage due to elevated DNA:RNA hybrids.

DNA:RNA hybrids, nucleic acid structures with diverse physiological functions, can disrupt genome integrity when dysregulated. Human telomeres were shown to form hybrids with the lncRNA TERRA, yet the formation and distribution of these hybrids among telomeres, their regulation and their cellular effects remain elusive. Here we predict and confirm in several human cell types that DNA:RNA hybrids form at many subtelomeric and telomeric regions. We demonstrate that ICF syndrome cells, which exhibit short telomeres and elevated TERRA levels, are enriched for hybrids at telomeric regions throughout the cell cycle. Telomeric hybrids are associated with high levels of DNA damage at chromosome ends in ICF cells, which are significantly reduced with overexpression of RNase H1. Our findings suggest that abnormally high TERRA levels in ICF syndrome lead to accumulation of telomeric hybrids that, in turn, can result in telomeric dysfunction

Bimetallic Coordination Insertion Polymerization of Unprotected Polar Monomers: Copolymerization of Amino Olefins and Ethylene by Dinickel Bisphenoxyiminato Catalysts

Dinickel bisphenoxyiminato complexes based on highly substituted p- and m-terphenyl backbones were synthesized, and the corresponding atropisomers were isolated. In the presence of a phosphine scavenger, Ni(COD)_2, the phosphine-ligated syn-dinickel complexes copolymerized α-olefins and ethylene in the presence of amines to afford 0.2–1.3% α-olefin incorporation and copolymerized amino olefins and ethylene with a similar range of incorporation (0.1–0.8%). The present rigid catalysts provide a bimetallic strategy for insertion polymerization of polar monomers without masking of the heteroatom group. The effects of the catalyst structure on the reactivity were studied by comparisons of the syn and anti atropisomers and the p- and m-terphenyl systems

Accretion Disk Spectra of the Ultra-luminous X-ray Sources in Nearby Spiral Galaxies and Galactic Superluminal Jet Sources

Ultra-luminous Compact X-ray Sources (ULXs) in nearby spiral galaxies and Galactic superluminal jet sources share the common spectral characteristic that they have unusually high disk temperatures which cannot be explained in the framework of the standard optically thick accretion disk in the Schwarzschild metric. On the other hand, the standard accretion disk around the Kerr black hole might explain the observed high disk temperature, as the inner radius of the Kerr disk gets smaller and the disk temperature can be consequently higher. However, we point out that the observable Kerr disk spectra becomes significantly harder than Schwarzschild disk spectra only when the disk is highly inclined. This is because the emission from the innermost part of the accretion disk is Doppler-boosted for an edge-on Kerr disk, while hardly seen for a face-on disk. The Galactic superluminal jet sources are known to be highly inclined systems, thus their energy spectra may be explained with the standard Kerr disk with known black hole masses. For ULXs, on the other hand, the standard Kerr disk model seems implausible, since it is highly unlikely that their accretion disks are preferentially inclined, and, if edge-on Kerr disk model is applied, the black hole mass becomes unreasonably large (> 300 M_solar). Instead, the slim disk (advection dominated optically thick disk) model is likely to explain the observed super-Eddington luminosities, hard energy spectra, and spectral variations of ULXs. We suggest that ULXs are accreting black holes with a few tens of solar mass, which is not unexpected from the standard stellar evolution scenario, and that their X-ray emission is from the slim disk shining at super-Eddington luminosities.Comment: ApJ, accepte

Preliminary trials on the optimization of hormone dosages for induced breeding of Philippine silver perch, Leiopotherapon plumbeus

Abstract only.The silver perch Leiopotherapon plumbeus, locally known as ayungin, is an endemic freshwater fish that is commercially valuable as it commands a high price in the local market. Due to excessive fishing and other potential causes such as predation by invasive alien species, the local L. plumbeus stocks are observed to be depleting hence there is a need for an induced breeding protocol to propagate silver perch and conserve what remains of the resource. In this study, 30 females (total length or TL: 109.4 ± 12.2 mm; total body weight or TBW: 20.3 ± 6.1 g) and 60 males (TL: 97.1 ± 11.6 mm; TBW: 13.4 ± 5.5 g) were injected once intra-muscularly with different doses of hormones. Various dosages of human chorionic gonadotropin (HCG), luteinizing hormone releasing hormone analog (LHRHa) and salmon gonadotropin releasing hormone (sGnRH) were evaluated to identify the most effective dosage and hormone that resulted to high ovulation, fertilization and hatching rate. For the hormone sGnRH, 20, 30 and 40 µg/kg body weight (BW) and 1, 2 and 3 µg/kg BW for LHRHa were the dosages used in the experiment. The dosage used for HCG is 50 IU/g BW and served as the control. The findings of the experiment determined that the use of 20 µg/kg body weight of sGnRH resulted to high ovulation, fertilization and hatching rates. The result of the experiment would provide an efficient protocol for the local fishermen so they can produce, on demand, a large supply of this high quality fish species

Chandra Observations of A Galactic Supernova Remnant Vela Jr.: A New Sample of Thin Filaments Emitting Synchrotron X-Rays

A galactic supernova remnant (SNR) Vela Jr. (RX J0852.0$-$4622, G266.6$-$1.2) shows sharp filamentary structure on the north-western edge of the remnant in the hard X-ray band. The filaments are so smooth and located on the most outer side of the remnant. We measured the averaged scale width of the filaments ($w_u$ and $w_d$) with excellent spatial resolution of {\it Chandra}, which are in the order of the size of the point spread function of {\it Chandra} on the upstream side and 49.5 (36.0--88.8) arcsec on the downstream side, respectively. The spectra of the filaments are very hard and have no line-like structure, and were well reproduced with an absorbed power-law model with $\Gamma =$2.67 (2.55--2.77), or a {\tt SRCUT} model with $\nu_{rolloff}$ = 4.3 (3.4--5.3)$\times 10^{16}$ Hz under the assumption of $p=0.3$. These results imply that the hard X-rays are synchrotron radiation emitted by accelerated electrons, as mentioned previously. Using a correlation between a function ${\cal B} \equiv \nu_{rolloff}/w_d^2$ and the SNR age, we estimated the distance and the age of Vela Jr.: the estimated distance and age are 0.33 (0.26--0.50) kpc and 660 (420--1400) years, respectively. These results are consistent with previous reports, implying that ${\cal B}$--age relation may be a useful tool to estimate the distance and the age of synchrotron X-ray emitting SNRs.Comment: 19 pages, 8 figures, ApJ, in pres