69 research outputs found
A Tight Upper Limit on Oscillations in the Ap star Epsilon Ursae Majoris from WIRE Photometry
Observations of Epsilon UMa obtained with the star tracker on the Wide Field
Infrared Explorer (WIRE) satellite during a month in mid-2000 are analyzed.
This is one of the most precise photometry of an Ap star. The amplitude
spectrum is used to set an upper limit of 75 parts per million for the
amplitude of stellar pulsations in this star unless it accidentally oscillates
with a single mode at the satellite orbit, its harmonics or their one day
aliases. This is the tightest limit put on the amplitude of oscillations in an
Ap star. As the rotation period of Epsilon UMa is relatively short (5.1 d), it
cannot be argued that the observations were made at a wrong rotational phase.
Our results thus support the idea that some Ap stars do not pulsate at all.Comment: 4 pages, 4 figures, 2 style files, accepted for publication in ApJ
Four-colour photometry of eclipsing binaries. XLI uvby light curves for AD Bootis, HW Canis Majoris, SW Canis Majoris, V636 Centauri, VZ Hydrae, and WZ Ophiuchi
CONTEXT: Accurate mass, radius, and abundance determinations from binaries
provide important information on stellar evolution, fundamental to central
fields in modern astrophysics and cosmology.
AIMS: Within the long-term Copenhagen Binary Project, we aim to obtain
high-quality light curves and standard photometry for double-lined detached
eclipsing binaries with late A, F, and G type main-sequence components, needed
for the determination of accurate absolute dimensions and abundances, and for
detailed comparisons with results from recent stellar evolutionary models.
METHODS: Between March 1985 and July 2007, we carried out photometric
observations of AD Boo, HW CMA, SW CMa, V636 Cen, VZ Hya, and WZ Oph at the
Str"omgren Automatic Telescope at ESO, La Silla.
RESULTS: We obtained complete uvby light curves, ephemerides, and standard
uvby\beta indices for all six systems.For V636 Cen and HW CMa, we present the
first modern light curves, whereas for AD Boo, SW CMa, VZ Hya, and WZ Oph, they
are both more accurate and more complete than earlier data. Due to a high
orbital eccentricity (e = 0.50), combined with a low orbital inclination (i =
84.7), only one eclipse, close to periastron, occurs for HW CMa. For the two
other eccentric systems, V636 Cen (e = 0.134) and SW CMa (e = 0.316), apsidal
motion has been detected with periods of 5270 +/- 335 and 14900 +/- 3600 years,
respectively.Comment: Only change is: Bottom lines (hopefully) not truncated anymore.
Accepted for publication in Astonomy & Astrophysic
Special considerations in the management of adult patients with acute leukaemias and myeloid neoplasms in the COVID-19 era: recommendations from a panel of international experts
Special considerations in the management of adult patients with acute leukaemias and myeloid neoplasms in the COVID-19 era: recommendations from a panel of international experts
This article is made available for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.The ongoing COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 is a global public health crisis. Multiple observations indicate poorer post-infection outcomes for patients with cancer than for the general population. Herein, we highlight the challenges in caring for patients with acute leukaemias and myeloid neoplasms amid the COVID-19 pandemic. We summarise key changes related to service allocation, clinical and supportive care, clinical trial participation, and ethical considerations regarding the use of lifesaving measures for these patients. We recognise that these recommendations might be more applicable to high-income countries and might not be generalisable because of regional differences in health-care infrastructure, individual circumstances, and a complex and highly fluid health-care environment. Despite these limitations, we aim to provide a general framework for the care of patients with acute leukaemias and myeloid neoplasms during the COVID-19 pandemic on the basis of recommendations from international experts
Technology, ethics and religious language: early Anglophone Christian reactions to “cyberspace”
The very recent past has seen an upswing of scholarly interest not so much in the Internet and Web themselves but in the terms in which they have been discussed and understood. This article examines a remarkable effusion of writing in the 1990s that addressed the spiritual and ethical implications of “cyberspace”. Christian critics reacted in different ways to prophecies of technological revolution. Some saw ethical challenges in relation to economic and social exclusion and the nature of interpersonal relations. Others elaborated a semi-mystical evolutionary understanding of the Web as an ontologically concrete “space”. Others again revived older anxieties about the challenge apparently posed to human uniqueness and autonomy posed by computerisation more generally, which cyberspace threatened to magnify. However, this thinking did not occur in isolation from the sweep of Anglophone social thought. I suggest instead that the wider discourse about the ethics of the Internet and Web, both learned and popular, was infused at every level with religious imagery. As such, the article contributes to the ongoing debate on the extent to which the cultures of the UK and North America have been secularised: even if religious observance has declined, the English language still bears the marks of its Christian past
The Current Understanding of and Treatment Paradigm for Newly-Diagnosed TP53-Mutated Acute Myeloid Leukemia
About 10% of newly diagnosed and 20–30% of therapy-related acute myeloid leukemia (AML) harbors a TP53 mutation (mTP53-AML). Unfortunately, this biological subset predicts one of the worst prognoses among patients with AML, specifically a median overall survival of about 7 months with fewer than 10% of patients eventually cured of disease. Although remission rates appear to be increased with venetoclax-based, less-intensive regimens when compared with contemporary, intensive chemotherapy (55–65% vs. 40%), survival appears to be no different between the two approaches. Attempts to discern whether or not the prognosis of mTP53-AML is universally poor have centered around the study of concurrent cytogenetic risk and predicted TP53 allelic state, measurable residual disease status and the impact of conditioning intensity for patients proceeding to allogeneic hematopoietic stem cell transplantation. We discuss these considerations in this review and offer the current treatment approach to TP53-mutated AML
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Oral therapy for myelodysplastic syndromes/neoplasms and acute myeloid leukemia: a revolution in progress
Patients with myeloid neoplasms such as myelodysplastic syndromes/neoplasms (MDS) and acute myeloid leukemia (AML) are generally older, and many are not eligible for curative intent intensive therapies and/or allogeneic hematopoietic stem cell transplantation. While lower intensity, hypomethylating agent (HMA)-based therapies such as azacitidine+venetoclax have improved patient outcomes significantly, responses are not durable, and most patients die from disease-related complications. The approvals of oral HMAs such as cedazuridine-decitabine (C-DEC) and oral azacitidine (CC-486) have kindled the hope that myeloid malignancies may soon be treated with total oral therapy.
We review all-oral therapies including the approvals of C-DEC and CC-486 in MDS and AML, respectively, in addition to emerging all-oral therapies, both monotherapy and combination, in higher-risk (HR) MDS and AML.
Oral HMAs have the potential to be a convenient and efficacy-equivalent treatment option for patients with HR-MDS or AML and improve their quality of life by reducing clinic visits for medication administration. Total-oral therapy combinations, largely including an oral HMA 'backbone,' are in the early phases of clinical development, and it is our hope that well-designed trials employing these agents may soon allow the identification of optimal regimens that deliver effective disease-directed therapy with good tolerability
Lenalidomide in non-deletion 5q lower-risk myelodysplastic syndromes: a glass quarter full or three quarters empty?
The Current Understanding of and Treatment Paradigm for Newly-Diagnosed <i>TP53</i>-Mutated Acute Myeloid Leukemia
About 10% of newly diagnosed and 20–30% of therapy-related acute myeloid leukemia (AML) harbors a TP53 mutation (mTP53-AML). Unfortunately, this biological subset predicts one of the worst prognoses among patients with AML, specifically a median overall survival of about 7 months with fewer than 10% of patients eventually cured of disease. Although remission rates appear to be increased with venetoclax-based, less-intensive regimens when compared with contemporary, intensive chemotherapy (55–65% vs. 40%), survival appears to be no different between the two approaches. Attempts to discern whether or not the prognosis of mTP53-AML is universally poor have centered around the study of concurrent cytogenetic risk and predicted TP53 allelic state, measurable residual disease status and the impact of conditioning intensity for patients proceeding to allogeneic hematopoietic stem cell transplantation. We discuss these considerations in this review and offer the current treatment approach to TP53-mutated AML
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