126 research outputs found
The Full-sky Astrometric Mapping Explorer -- Astrometry for the New Millennium
FAME is designed to perform an all-sky, astrometric survey with unprecedented
accuracy. It will create a rigid astrometric catalog of 4x10^7 stars with 5 <
m_V < 15. For bright stars, 5 < m_V < 9, FAME will determine positions and
parallaxes accurate to < 50 microarcseconds, with proper motion errors < 50
microarcseconds/year. For fainter stars, 9 < m_V < 15, FAME will determine
positions and parallaxes accurate to < 500 microarcseconds, with proper motion
errors < 500 microarcseconds/year. It will also collect photometric data on
these 4 x 10^7 stars in four Sloan DSS colors.Comment: 6 pages, 4 figures, to appear in "Working on the Fringe
Laryngeal transplantation in minipigs: vascular, myologic and functional outcomes
There is no effective way of replacing all the functions of the larynx in those requiring laryngectomy. Regenerative medicine offers promise, but cannot presently deliver implants with functioning neuromuscular units. A single well-documented laryngeal transplant in man was a qualified success, but more information is required before clinical trials may be proposed. We studied the early response of the larynx to laryngeal transplantation between 17 pairs of NIH minipigs full matched at the MHC2 locus. Following iterative technical improvements, pigs had good swallowing and a patent airway at 1 week. No significant changes in mucosal blood flux were observed compared with pre-operative measurements. Changes in muscle morphology and fibre phenotype were observed in transplant muscles retrieved after 7 days: the levels of fast and slow myosin heavy chain (MyHC) protein were reduced and embryonic MyHC was up regulated consistent with denervation induced atrophy. At 1 week laryngeal transplantation can result in good swallowing, and is not associated with clinical evidence of ischemia-reperfusion injury in MHC-matched pigs
Long-term evolution of orbits about a precessing oblate planet: 1. The case of uniform precession
It was believed until very recently that a near-equatorial satellite would
always keep up with the planet's equator (with oscillations in inclination, but
without a secular drift). As explained in Efroimsky and Goldreich (2004), this
opinion originated from a wrong interpretation of a (mathematically correct)
result obtained in terms of non-osculating orbital elements. A similar analysis
carried out in the language of osculating elements will endow the planetary
equations with some extra terms caused by the planet's obliquity change. Some
of these terms will be nontrivial, in that they will not be amendments to the
disturbing function. Due to the extra terms, the variations of a planet's
obliquity may cause a secular drift of its satellite orbit inclination. In this
article we set out the analytical formalism for our study of this drift. We
demonstrate that, in the case of uniform precession, the drift will be
extremely slow, because the first-order terms responsible for the drift will be
short-period and, thus, will have vanishing orbital averages (as anticipated 40
years ago by Peter Goldreich), while the secular terms will be of the second
order only. However, it turns out that variations of the planetary precession
make the first-order terms secular. For example, the planetary nutations will
resonate with the satellite's orbital frequency and, thereby, may instigate a
secular drift. A detailed study of this process will be offered in the
subsequent publication, while here we work out the required mathematical
formalism and point out the key aspects of the dynamics
The spectrum and clinical impact of epigenetic modifier mutations in myeloma
Epigenetic dysregulation is known to be an important contributor to myeloma pathogenesis but, unlike in other B cell malignancies, the full spectrum of somatic mutations in epigenetic modifiers has not been previously reported. We sought to address this using results from whole-exome sequencing in the context of a large prospective clinical trial of newly diagnosed patients and targeted sequencing in a cohort of previously treated patients for comparison.Whole-exome sequencing analysis of 463 presenting myeloma cases entered in the UK NCRI Myeloma XI study and targeted sequencing analysis of 156 previously treated cases from the University of Arkansas for Medical Sciences. We correlated the presence of mutations with clinical outcome from diagnosis and compared the mutations found at diagnosis with later stages of disease.In diagnostic myeloma patient samples we identify significant mutations in genes encoding the histone 1 linker protein, previously identified in other B-cell malignancies. Our data suggest an adverse prognostic impact from the presence of lesions in genes encoding DNA methylation modifiers and the histone demethylase KDM6A/UTX. The frequency of mutations in epigenetic modifiers appears to increase following treatment most notably in genes encoding histone methyltransferases and DNA methylation modifiers.Numerous mutations identified raise the possibility of targeted treatment strategies for patients either at diagnosis or relapse supporting the use of sequencing-based diagnostics in myeloma to help guide therapy as more epigenetic targeted agents become available
Amyloid Beta and Tau Cooperate to Cause Reversible Behavioral and Transcriptional Deficits in a Model of Alzheimer's Disease
Statistics versus livelihoods: questioning Rwanda’s pathway out of poverty
Recent statistics indicate that poverty in Rwanda decreased impressively between 2006 and 2014. This seems to confirm Rwanda’s developmental progress. This article however argues for a more cautious interpretation of household survey data. The authors contrast macro-level statistical analysis with in-depth field research on livelihood conditions. Macro-economic numbers provide interesting information, however differentiated evidence is required to understand how poverty ‘works’ in everyday life. On the basis of the Rwandan case study, the authors conclude that because of the high political stakes of data collection and analysis, and given that relations of power influence the production of knowledge on poverty, cross-checking is crucial
The supernatural characters and powers of sacred trees in the Holy Land
This article surveys the beliefs concerning the supernatural characteristics and powers of sacred trees in Israel; it is based on a field study as well as a survey of the literature and includes 118 interviews with Muslims and Druze. Both the Muslims and Druze in this study attribute supernatural dimensions to sacred trees which are directly related to ancient, deep-rooted pagan traditions. The Muslims attribute similar divine powers to sacred trees as they do to the graves of their saints; the graves and the trees are both considered to be the abode of the soul of a saint which is the source of their miraculous powers. Any violation of a sacred tree would be strictly punished while leaving the opportunity for atonement and forgiveness. The Druze, who believe in the transmigration of souls, have similar traditions concerning sacred trees but with a different religious background. In polytheistic religions the sacred grove/forest is a centre of the community's official worship; any violation of the trees is regarded as a threat to the well being of the community. Punishments may thus be collective. In the monotheistic world (including Christianity, Islam and Druze) the pagan worship of trees was converted into the worship/adoration of saints/prophets; it is not a part of the official religion but rather a personal act and the punishments are exerted only on the violating individual
Work and Mental Complaints: Are Response Outcome Expectancies More Important Than Work Conditions and Number of Subjective Health Complaints?
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