4,202 research outputs found
ROR2 (receptor tyrosine kinase-like orphan receptor 2)
Review on ROR2 (receptor tyrosine kinase-like orphan receptor 2), with data on DNA, on the protein encoded, and where the gene is implicated
Ultraluminous Infrared Galaxies
At luminosities above ~10^{11} L_sun, infrared galaxies become the dominant
population of extragalactic objects in the local Universe (z < 0.5), being more
numerous than optically selected starburst and Seyfert galaxies, and QSOs at
comparable bolometric luminosity. At the highest luminosities, ultraluminous
infrared galaxies (ULIGs: L_ir > 10^{12} L_sun), outnumber optically selected
QSOs by a factor of ~1.5-2. All of the nearest ULIGs (z < 0.1) appear to be
advanced mergers that are powered by both a circumnuclear starburst and AGN,
both of which are fueled by an enormous concentration of molecular gas
(~10^{10} M_sun) that has been funneled into the merger nucleus. ULIGs may
represent a primary stage in the formation of massive black holes and
elliptical galaxy cores. The intense circumnuclear starburst that accompanies
the ULIG phase may also represent a primary stage in the formation of globular
clusters, and the metal enrichment of the intergalactic medium by gas and dust
expelled from the nucleus due to the combined forces of supernova explosions
and powerful stellar winds.Comment: LaTex, 6 pages with 4 embedded .eps figures. Postscript version plus
color plates available at
http://www.ifa.hawaii.edu/users/sanders/astroph/s186/plates.html To appear in
"Galaxy Interactions at Low and High Redshift" IAU Symposium 186, Kyoto,
Japan, eds. J.E. Barnes and D.B. Sander
Time-dependent response of a zonally averaged oceanâatmosphereâsea ice model to Milankovitch forcing
Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Springer-Verlag for personal use, not for redistribution. The definitive version was published in Climate Dynamics 6 (2010): 763-779, doi:10.1007/s00382-010-0790-6.An ocean-atmosphere-sea ice model is developed to explore the time-dependent
response of climate to Milankovitch forcing for the time interval 5-3 Myr BP. The ocean
component is a zonally averaged model of the circulation in five basins (Arctic, Atlantic,
Indian, Pacific, and Southern Oceans). The atmospheric component is a one-dimensional
(latitudinal) energy balance model, and the sea-ice component is a thermodynamic model.
Two numerical experiments are conducted. The first experiment does not include sea ice
and the Arctic Ocean; the second experiment does. Results from the two experiments are
used to investigate (i) the response of annual mean surface air and ocean temperatures to
Milankovitch forcing, and (ii) the role of sea ice in this response.
In both experiments, the response of air temperature is dominated by obliquity cycles
at most latitudes. On the other hand, the response of ocean temperature varies with latitude
and depth. Deep water formed between 45°N-65°N in the Atlantic Ocean mainly responds
to precession. In contrast, deep water formed south of 60°S responds to obliquity when sea
ice is not included. Sea ice acts as a time-integrator of summer insolation changes such that
annual mean sea-ice conditions mainly respond to obliquity. Thus, in the presence of sea
ice, air temperature changes over the sea ice are amplified, and temperature changes in deep
water of southern origin are suppressed since water below sea ice is kept near the freezing
point.This work was supported by an NSERC Discovery
Grant awarded to L.A.M. We also thank GEC3 for a Network Grant
Structure-Based Design of Potent and Selective Leishmania N-Myristoyltransferase Inhibitors
Inhibitors of Leishmania N-myristoyltransferase (NMT), a potential target for the treatment of leishmaniasis, obtained from a high-throughput screen, were resynthesized to validate activity. Crystal structures bound to Leishmania major NMT were obtained, and the active diastereoisomer of one of the inhibitors was identified. On the basis of structural insights, enzyme inhibition was increased 40-fold through hybridization of two distinct binding modes, resulting in novel, highly potent Leishmania donovani NMT inhibitors with good selectivity over the human enzyme
Infant cortex responds to other humans from shortly after birth
A significant feature of the adult human brain is its ability to selectively process information about conspecifics. Much debate has centred on whether this specialization is primarily a result of phylogenetic adaptation, or whether the brain acquires expertise in processing social stimuli as a result of its being born into an intensely social environment. Here we study the haemodynamic response in cortical areas of newborns (1â5 days old) while they passively viewed dynamic human or mechanical action videos. We observed activation selective to a dynamic face stimulus over bilateral posterior temporal cortex, but no activation in response to a moving human arm. This selective activation to the social stimulus correlated with age in hours over the first few days post partum. Thus, even very limited experience of face-to-face interaction with other humans may be sufficient to elicit social stimulus activation of relevant cortical regions
Justice at Sea: Fishersâ politics and marine conservation in coastal Odisha, India
This is a paper about the politics of fishing rights in and around the Gahirmatha marine sanctuary in coastal Odisha, in eastern India. Claims to the resources of this sanctuary are politicised through the creation of a particularly damaging narrative by influential Odiya environmental actors about Bengalis, as illegal immigrants who have hurt the ecosystem through their fishing practices. Anchored within a theoretical framework of justice as recognition, the paper considers the making of a regional Odiya environmentalism that is, potentially, deeply exclusionary. It details how an argument about âillegal Bengalisâ depriving âindigenous Odiyasâ of their legitimate âtraditional fishing rightsâ derives from particular notions of indigeneity and territory. But the paper also shows that such environmentalism is tenuous, and fits uneasily with the everyday social landscape of fishing in coastal Odisha. It concludes that a wider class conflict between small fishers and the state over a sanctuary sets the context in which questions about legitimate resource rights are raised, sometimes with important effects, like when out at sea
The effects of supernovae on the dynamical evolution of binary stars and star clusters
In this chapter I review the effects of supernovae explosions on the
dynamical evolution of (1) binary stars and (2) star clusters.
(1) Supernovae in binaries can drastically alter the orbit of the system,
sometimes disrupting it entirely, and are thought to be partially responsible
for `runaway' massive stars - stars in the Galaxy with large peculiar
velocities. The ejection of the lower-mass secondary component of a binary
occurs often in the event of the more massive primary star exploding as a
supernova. The orbital properties of binaries that contain massive stars mean
that the observed velocities of runaway stars (10s - 100s km s) are
consistent with this scenario.
(2) Star formation is an inherently inefficient process, and much of the
potential in young star clusters remains in the form of gas. Supernovae can in
principle expel this gas, which would drastically alter the dynamics of the
cluster by unbinding the stars from the potential. However, recent numerical
simulations, and observational evidence that gas-free clusters are observed to
be bound, suggest that the effects of supernova explosions on the dynamics of
star clusters are likely to be minimal.Comment: 16 pages, to appear in the 'Handbook of Supernovae', eds. Paul Murdin
and Athem Alsabti. This version replaces an earlier version that contained
several typo
Standardisation of intestinal ultrasound scoring in clinical trials for luminal Crohn's disease
Background: Intestinal ultrasound (IUS) is a valuable tool for assessment of Crohnâs disease (CD). However, there is no widely accepted luminal disease activity index. /
Aims: To identify appropriate IUS protocols, indices, items, and scoring methods for measurement of luminal CD activity and integration of IUS in CD clinical trials. /
Methods: An expert international panel of adult and paediatric gastroenterologists (n = 15) and radiologists (n = 3) rated the appropriateness of 120 statements derived from literature review and expert opinion (scale of 1-9) using modified RAND/UCLA methodology. Median panel scores of 1 to â€3.5, >3.5 to <6.5 and â„6.5 to 9 were considered inappropriate, uncertain and appropriate ratings respectively. The statement list and survey results were discussed prior to voting. /
Results: A total of 91 statements were rated appropriate with agreement after two rounds of voting. Items considered appropriate measures of disease activity were bowel wall thickness (BWT), vascularity, stratification and mesenteric inflammatory fat. There was uncertainty if any of the existing IUS disease activity indices were appropriate for use in CD clinical trials. Appropriate trial applications for IUS included patient recruitment qualification when diseased segments cannot be adequately assessed by ileocolonoscopy and screening for exclusionary complications. At outcome assessment, remission endpoints including BWT and vascularity, with or without mesenteric inflammatory fat, were considered appropriate. Components of an ideal IUS disease activity index were identified based upon panel discussions. /
Conclusions: The panel identified appropriate component items and applications of IUS for CD clinical trials. Empiric evidence, and development and validation of an IUS disease activity index are needed
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