18 research outputs found
Integral Field Spectroscopy of Supernova Remnant 1E0102-7219 Reveals Fast-moving Hydrogen and Sulfur-rich Ejecta
We study the optical emission from heavy element ejecta in the oxygen-rich
young supernova remnant (SNR) 1E 0102.2-7219 (1E 0102) in the Small Magellanic
Cloud. We have used the Multi-Unit Spectroscopic Explorer (MUSE) optical
integral field spectrograph at the Very Large Telescope (VLT) on Cerro Paranal
and the wide field spectrograph (WiFeS) at the ANU 2.3 m telescope at Siding
Spring Observatory to obtain deep observations of 1E 0102. Our observations
cover the entire extent of the remnant from below 3500{\AA} to 9350{\AA}. Our
observations unambiguously reveal the presence of fast-moving ejecta emitting
in [S II], [S III], [Ar III], and [Cl II]. The sulfur-rich ejecta appear more
asymmetrically distributed compared to oxygen or neon, a product of
carbon-burning. In addition to the forbidden line emission from products of
oxygen burning (S, Ar, Cl), we have also discovered H{\alpha} and H{\beta}
emission from several knots of low surface brightness, fast-moving ejecta. The
presence of fast-moving hydrogen points towards a progenitor that had not
entirely shed its hydrogen envelope prior to the supernova. The explosion that
gave rise to 1E 0102 is therefore commensurate with a Type IIb supernova.Comment: 10 pages, 4 multi-panel figures, 1 table; accepted for publication in
The Astrophysical Journal Letter
Encephalitis with coinfection by Jamestown canyon virus (JCV) and varicella zoster virus (VZV)
We present the case of a 59-year-old Midwestern farmer who presented with altered mental status, dysarthria, urinary incontinence, and a right-sided L5 dermatomal rash; he had recently received a course of oral corticosteroids for treatment of radicular low back pain. Lumbar puncture revealed the presence of varicella zoster virus (VZV) and IgM antibodies against a California-group encephalitis virus, later confirmed as Jamestown Canyon virus (JCV). Unfortunately, the patient’s health declined despite aggressive treatment, developing progressive subarachnoid hemorrhage. He died after withdrawal of supportive care following 3 weeks in the intensive care unit. To our knowledge, this is the first documented case of encephalitis associated with coinfection by VZV and JCV. While the relative contributions of these viral pathogens to the patient’s illness are difficult to ascertain, the clinical features of this case are consistent with co-pathogenesis, possibly driven by antecedent corticosteroid use. This case highlights the emerging role of viral coinfections in the etiology of viral illnesses
Integral Field Spectroscopy of Balmer-dominated Shocks in the Magellanic Cloud Supernova Remnant N103B
We present results of integral field spectroscopy of Balmer-dominated shocks in the LMC supernova remnant (SNR) N103B, carried out using the Wide Field Integral Spectrograph (WiFeS ) on the 2.3 m telescope at the Siding Spring Observatory in Australia. Existing X-ray studies of N103B have indicated an SN Ia origin. Radiative shock emission from clumpy material surrounding the SNR may result from interaction of the forward shock with relic stellar wind material, possibly implicating a thermonuclear explosion in a single-degenerate binary system. The recently discovered Balmer-dominated shocks mark the impact of the forward shock with low density, partially neutral CSM gas, and form a partial shell encircling clumps of material exhibiting radiative shocks. The WiFeS spectra of N103B reveal broad Hα emission having a width as high as 2350 km s−1 along the northern rim, and both Hα and Hβ broad profiles having widths around 1300 km s−1 along the southern rim. Fits to the Hα line profiles indicate that in addition to the usual broad and narrow emission components, a third component of intermediate width exists in these Balmer-dominated shocks, ranging from around 125 km s−1 up to 225 km s−1 in width. This is consistent with predictions of recent Balmer-dominated shock models, which predict that an intermediate-width component will be generated in a fast neutral precursor. We derive a Sedov age of approximately 685 ± 20 years for N103B from the Balmer-dominated spectra, consistent with the young age of 380–860 years estimated from light echo studies
A phase II evaluation of gefitinib in the treatment of persistent or recurrent endometrial cancer: a Gynecologic Oncology Group study.
BackgroundA phase II trial was performed to evaluate the efficacy and safety of gefitinib in patients with persistent/recurrent endometrial cancer.MethodsWomen with histologically confirmed persistent/recurrent endometrial cancer were treated with 500mg oral gefitinib daily until progression or severe toxicity, with progression-free survival (PFS) at six months as the primary endpoint. Tumor expression of total epidermal growth factor receptor (EGFR), estrogen receptor (ER), progesterone receptor A (PRA) and B (PRB), Ki67, pEGFR and activated extracellular signal-regulated kinase (pERK) were examined pre- and post-treatment. EGFR was sequenced, and serum concentrations of soluble EGFR (sEGFR) at baseline also were examined.ResultsOf 29 patients enrolled, 26 were evaluable for efficacy and toxicity. Four patients experienced PFS ≥6 months, and one had a complete response which was not associated with an EGFR mutation. The concentration of sEGFR in pretreatment serum was positively correlated with overall survival (OS), but not with responsiveness to gefitinib in this small patient cohort. Expression of tumor biomarkers was not associated with PFS or OS. Co-expression of ER with PRA in primary and recurrent tumors, and pEGFR with pERK in primary tumors was observed.ConclusionsThis treatment regimen was tolerable but lacked sufficient efficacy to warrant further evaluation in this setting. The possible association between serum sEGFR concentrations and OS, and temporal changes in expression of pEGFR and pERK and the documented CR of one patient are interesting and warrant additional investigation