75 research outputs found
The Lantern Vol. 11, No. 3, May 1943
• Women\u27s Ward: Byberry • Ballad of Courtin\u27 • Burnished Armor • A Tribute • The Aeolian Harp • There is a Tide • Translation of a Greek Drinking Song • Query • Lemuel Lepidoptera • Quatrain • Ode to Spring • Though You\u27re Far Awayhttps://digitalcommons.ursinus.edu/lantern/1030/thumbnail.jp
The Lantern Vol. 10, No. 3, May 1942
• Isn\u27t This Fine Weather? • Girls\u27 Rules Through Twenty Years • Lost: Imagination--Gained: Sanitation • Ursinus During the First World War • Inspirations From a Concert Hall • Brother Jones • The Sea and Cloud and Sky--No More • Literary Prattle • War and Memories • Springhttps://digitalcommons.ursinus.edu/lantern/1027/thumbnail.jp
The Lantern Vol. 11, No. 1, December 1942
• Friends of the Aquarium • Espionage • Fuss-Budget • Dress Blues • Alone • One Easy Lesson in How Not to Study • A Thumbtack Sketch • One Star • A Colonial Inn • Thoughts on a Dark Day • Query • Paul Revere and the World He Lived In • Sunsetshttps://digitalcommons.ursinus.edu/lantern/1028/thumbnail.jp
Understanding the LMXB X2127+119 in M15
We present HST UV observations of the high-inclination low mass X-ray binary
AC211 (X2127+119), which is located in the globular cluster M15 (NGC 7078). We
have discovered a CIV P Cygni profile in this system, which confirms the
existence of an outflow from AC211. The outflow velocity as measured from the P
Cygni profile is 1500km/s. We calculate that the mass lost through this wind is
too small to support a large period derivative as favoured by Homer & Charles
(1998). Using new X-ray observations we have revised the ephemeris for AC211
and we find no evidence in support of a period derivative. The UV spectrum
exhibits several absorption features due to O, Si and C. The very strong HeII
line at 1640A is not seen to modulate strongly with orbital phase, suggesting
its origin lies in the outer parts of the system. In contrast, the eclipse of
the UV continuum is short compared with the X-ray and optical eclipses.Comment: Accepted for Astronomy and Astrophysics. 9 pages and 6 figure
Global optical/infrared - X-ray correlations in X-ray binaries: quantifying disc and jet contributions
The optical/near-infrared (OIR) region of the spectra of low-mass X-ray
binaries appears to lie at the intersection of a variety of different emission
processes. In this paper we present quasi-simultaneous OIR - X-ray observations
of 33 XBs in an attempt to estimate the contributions of various emission
processes in these sources, as a function of X-ray state and luminosity. A
global correlation is found between OIR and X-ray luminosity for low-mass black
hole candidate XBs (BHXBs) in the hard X-ray state, of the form L_OIR is
proportional to Lx^0.6. This correlation holds over 8 orders of magnitude in Lx
and includes data from BHXBs in quiescence and at large distances (LMC and
M31). A similar correlation is found in low-mass neutron star XBs (NSXBs) in
the hard state. For BHXBs in the soft state, all the near-infrared (NIR) and
some of the optical emission is suppressed below the correlation, a behaviour
indicative of the jet switching off/on in transition to/from the soft state. We
compare these relations to theoretical models of a number of emission
processes. We find that X-ray reprocessing in the disc and emission from the
jets both predict a slope close to 0.6 for BHXBs, and both contribute to the
OIR in BHXBs in the hard state, the jets producing ~90 percent of the NIR
emission at high luminosities. X-ray reprocessing dominates the OIR in NSXBs in
the hard state, with possible contributions from the jets (only at high
luminosity) and the viscously heated disc. We also show that the optically
thick jet spectrum of BHXBs extends to near the K-band. (abridged)Comment: Accepted for publication in MNRAS; 19 pages, 7 figure
In silico design and biological evaluation of a dual specificity kinase inhibitor targeting cell cycle progression and angiogenesis
Methodology: We have utilized a rational in silico-based approach to demonstrate the design and study of a novel compound that acts as a dual inhibitor of vascular endothelial growth factor receptor 2 (VEGFR2) and cyclin-dependent kinase 1 (CDK1). This compound acts by simultaneously inhibiting pro-Angiogenic signal transduction and cell cycle progression in primary endothelial cells. JK-31 displays potent in vitro activity against recombinant VEGFR2 and CDK1/cyclin B proteins comparable to previously characterized inhibitors. Dual inhibition of the vascular endothelial growth factor A (VEGF-A)-mediated signaling response and CDK1-mediated mitotic entry elicits anti-Angiogenic activity both in an endothelial-fibroblast co-culture model and a murine ex vivo model of angiogenesis
VEGF-A isoforms differentially regulate ATF-2-dependent VCAM-1 gene expression and endothelial-leukocyte interactions
Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology. VEGF-A stimulates signal transduction pathways that modulate endothelial outputs such as cell migration, proliferation, tubulogenesis, and cell-cell interactions. Multiple VEGF-A isoforms exist, but the biological significance of this is unclear. Here we analyzed VEGF-A isoform-specific stimulation of VCAM-1 gene expression, which controls endothelial-leukocyte interactions, and show that this is dependent on both ERK1/2 and activating transcription factor-2 (ATF-2). VEGF-A isoforms showed differential ERK1/2 and p38 MAPK phosphorylation kinetics. A key feature of VEGF-A isoform-specific ERK1/2 activation and nuclear translocation was increased phosphorylation of ATF-2 on threonine residue 71 (T71). Using reverse genetics, we showed ATF-2 to be functionally required for VEGF-A-stimulated endothelial VCAM-1 gene expression. ATF-2 knockdown blocked VEGF-A-stimulated VCAM-1 expression and endothelial-leukocyte interactions. ATF-2 was also required for other endothelial cell outputs, such as cell migration and tubulogenesis. In contrast, VCAM-1 was essential only for promoting endothelial-leukocyte interactions. This work presents a new paradigm for understanding how soluble growth factor isoforms program complex cellular outputs and responses by modulating signal transduction pathways
Print awareness of adult illiterates: a comparison with young pre-readers and low-educated adult readers
In this study the print awareness of 25 unschooled adult illiterates in the Netherlands was compared with that of 24 pre-reading children and of 23 low-educated literate adults with approximately four years of primary schooling. The illiterates were interviewed about their experiences with writing and all participants completed six assessments of print awareness in the language they preferred (first or second language). The outcomes revealed that the three groups did not differ in distinguishing conventional written signs from other visual signs, that both groups of non-readers differed significantly from low educated readers but not from each other in knowledge of logos, inscriptions and knowledge of the written register, while the adult illiterates performed significantly better than the children on grapheme knowledge. Adult illiterates in literate societies seem to be well informed about the uses and functions of written language and about what writing looks like, but like young children they are not good at reading environmental print out of context and in explaining what exactly is represented in writing. The variation in reactions within the group of illiterate adults could be related to existing models of emergent literacy. Implications for adult literacy education are discussed
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