Pixel-z: Studying Substructure and Stellar Populations in Galaxies out to z~3 using Pixel Colors I. Systematics

We perform a pixel-by-pixel analysis of 467 galaxies in the GOODS-VIMOS survey to study systematic effects in extracting properties of stellar populations (age, dust, metallicity and SFR) from pixel colors using the pixel-z method. The systematics studied include the effect of the input stellar population synthesis model, passband limitations and differences between individual SED fits to pixels and global SED-fitting to a galaxy's colors. We find that with optical-only colors, the systematic errors due to differences among the models are well constrained. The largest impact on the age and SFR e-folding time estimates in the pixels arises from differences between the Maraston models and the Bruzual&Charlot models, when optical colors are used. This results in systematic differences larger than the 2{\sigma} uncertainties in over 10 percent of all pixels in the galaxy sample. The effect of restricting the available passbands is more severe. In 26 percent of pixels in the full sample, passband limitations result in systematic biases in the age estimates which are larger than the 2{\sigma} uncertainties. Systematic effects from model differences are reexamined using Near-IR colors for a subsample of 46 galaxies in the GOODS-NICMOS survey. For z > 1, the observed optical/NIR colors span the rest frame UV-optical SED, and the use of different models does not significantly bias the estimates of the stellar population parameters compared to using optical-only colors. We then illustrate how pixel-z can be applied robustly to make detailed studies of substructure in high redshift galaxies such as (a) radial gradients of age, SFR, sSFR and dust and (b) the distribution of these properties within subcomponents such as spiral arms and clumps. Finally, we show preliminary results from the CANDELS survey illustrating how the new HST/WFC3 data can be exploited to probe substructure in z~1-3 galaxies.Comment: 37 pages, 21 figures, submitted to Ap

Synchronizing Sequencing Software to a Live Drummer

Copyright 2013 Massachusetts Institute of Technology. MIT allows authors to archive published versions of their articles after an embargo period. The article is available at

A requirement for bone morphogenetic protein-7 during development of the mammalian kidney and eye.

BMP-7/OP-1, a member of the transforming growth factor-beta (TGF-beta) family of secreted growth factors, is expressed during mouse embryogenesis in a pattern suggesting potential roles in a variety of inductive tissue interactions. The present study demonstrates that mice lacking BMP-7 display severe defects confined to the developing kidney and eye. Surprisingly, the early inductive tissue interactions responsible for establishing both organs appear largely unaffected. However, the absence of BMP-7 disrupts the subsequent cellular interactions required for their continued growth and development. Consequently, homozygous mutant animals exhibit renal dysplasia and anophthalmia at birth. Overall, these findings identify BMP-7 as an essential signaling molecule during mammalian kidney and eye development

(1RS,4SR)-3-Dichloro­methyl­ene-1,4-dimethyl-2-oxabicyclo­[2.2.2]oct-5-ene

X-ray crystallography was used to confirm the structure of the enantio-enriched title compound, C10H12Cl2O, a bicylic enol ether. A bridged boat-like structure is adopted and the dichloro­methyl­ene C atom is positioned significantly removed from the core bicyclic unit. In the crystal structure, mol­ecules pack to form sheets approximately perpendicular to the a and c axes

Face recognition by Metropolitan Police super-recognisers

Face recognition is used to prove identity across a wide variety of settings. Despite this, research consistently shows that people are typically rather poor at matching faces to photos. Some professional groups, such as police and passport officers, have been shown to perform just as poorly as the general public on standard tests of face recognition. However, face recognition skills are subject to wide individual variation, with some people showing exceptional ability—a group that has come to be known as 'super-recognisers'. The Metropolitan Police Force (London) recruits 'super-recognisers' from within its ranks, for deployment on various identification tasks. Here we test four working super-recognisers from within this police force, and ask whether they are really able to perform at levels above control groups. We consistently find that the police 'super-recognisers' perform at well above normal levels on tests of unfamiliar and familiar face matching, with degraded as well as high quality images. Recruiting employees with high levels of skill in these areas, and allocating them to relevant tasks, is an efficient way to overcome some of the known difficulties associated with unfamiliar face recognition

Clustering of eastern North Pacific tropical cyclone tracks: ENSO and MJO effects

A probabilistic clustering technique is used to describe tropical cyclone tracks in the eastern North Pacific, on the basis of their shape and location. The best track data set is decomposed in terms of three clusters; these clusters are analyzed in terms of genesis location, trajectory, landfall, intensity, seasonality, and their relationships with the El Niño–Southern Oscillation (ENSO) and Madden-Julian Oscillation (MJO). Longitudinal track location plays a strong discriminating role in the regression mixture model's solution, with the average track orientation becoming more zonal toward the west. This progression encapsulates well the relationship between tropical cyclones over the eastern tropical Pacific and the MJO or ENSO. Two of the clusters describe tropical cyclones (TCs) with tracks that lie near the coast of Mexico and Central America. The most frequent cluster contains tracks that trend west-northwestward, while the second most frequent one has genesis locations that lie slightly to the southeast of those in the most frequent cluster and tracks that run typically parallel to the Central American coast. This second cluster is shown to be significantly associated with the westerly phase of the MJO. The third, least frequent cluster contains TCs with westward trajectories over the central and eastern equatorial Pacific; some of these TCs have an impact on Hawaii and other islands, as far as the central and western North Pacific regions. The least frequent cluster is strongly related to ENSO, while the others are not; it occurs significantly more frequently during El Niño conditions. Examination of the large-scale patterns of atmospheric circulation and sea surface temperature associated with each of our three clusters are consistent with previous studies. Anomalous low-level westerly zonal winds from the monsoon trough and MJO meet anomalous easterlies near the region of genesis in each cluster

Cluster Analysis of Typhoon Tracks. Part II: Large-Scale Circulation and ENSO

A new probabilistic clustering method, based on a regression mixture model, is used to describe tropical cyclone (TC) propagation in the western North Pacific (WNP). Seven clusters were obtained and described in Part I of this two-part study. In Part II, the present paper, the large-scale patterns of atmospheric circulation and sea surface temperature associated with each of the clusters are investigated, as well as associations with the phase of the El Niño–Southern Oscillation (ENSO). Composite wind field maps over the WNP provide a physically consistent picture of each TC type, and of its seasonality. Anomalous vorticity and outgoing longwave radiation indicate changes in the monsoon trough associated with different types of TC genesis and trajectory. The steering winds at 500 hPa are more zonal in the straight-moving clusters, with larger meridional components in the recurving ones. Higher values of vertical wind shear in the midlatitudes also accompany the straight-moving tracks, compared to the recurving ones. The influence of ENSO on TC activity over the WNP is clearly discerned in specific clusters. Two of the seven clusters are typical of El Niño events; their genesis locations are shifted southeastward and they are more intense. The largest cluster is recurving, located northwestward, and occurs more often during La Niña events. Two types of recurving and one of straight-moving tracks occur preferentially when the Madden–Julian oscillation is active over the WNP region

Reconstruction of fetal and infant anatomy using rapid prototyping of post-mortem MR images

OBJECTIVES: The recent decline in autopsy rates and lack of human anatomical material donated for research and training has resulted in issues for medical training in the United Kingdom. This study aims to examine the feasibility of making accurate three-dimensional (3D) models of the human body and visceral organs using post-mortem magnetic resonance (MR) imaging and rapid prototyping. METHODS: We performed post-mortem MR imaging using a 3D T2-weighted sequence in 11 fetuses and infants, before autopsy, using either a 1.5-T or 9.4-T MR scanner. Internal organs were reconstructed in silico and 3D models were created by rapid prototyping. RESULTS: The median gestation of fetuses was 20 (range 19-30) weeks and the median age of infants was 12 (range 8-16) weeks. Models created by rapid prototyping accurately depicted structural abnormalities and allowed clear visualisation of 3D relationships. CONCLUSIONS: Accurate 3D modelling of anatomical features from post-mortem imaging in fetuses and infants is feasible. These models could have a large number of medical applications, including improved parental counselling, invaluable teaching resources and significant medico-legal applications to demonstrate disease or injury, without the need to show actual autopsy photographs