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High throughput experimental approaches are increasingly allowing for the quantitative description of cellular and organismal phenotypes. Distilling these large volumes of complex data into meaningful measures that can drive biological insight remains a central challenge. In the quantitative study of development, for instance, one can resolve phenotypic measures for single cells onto their lineage history, enabling joint consideration of heritable signals and cell fate decisions. Most attempts to analyze this type of data, however, discard much of the information content contained within lineage trees. In this work we introduce a generalized metric, which we term the branch edit distance, that allows us to compare any two embryos based on phenotypic measurements in individual cells. This approach aligns those phenotypic measurements to the underlying lineage tree, providing a flexible and intuitive framework for quantitative comparisons between, for instance, Wild-Type (WT) and mutant developmental programs. We apply this novel metric to data on cell-cycle timing from over 1300 WT and RNAi-treated Caenorhabditis elegans embryos. Our new metric revealed surprising heterogeneity within this data set, including subtle batch effects in WT embryos and dramatic variability in RNAi-induced developmental phenotypes, all of which had been missed in previous analyses. Further investigation of these results suggests a novel, quantitative link between pathways that govern cell fate decisions and pathways that pattern cell cycle timing in the early embryo. Our work demonstrates that the branch edit distance we propose, and similar metrics like it, have the potential to revolutionize our quantitative understanding of organismal phenotype. Author summary: Lineage tracing has seen a renaissance as imaging and molecular technologies have made it possible to perform increasingly rich quantitative experiments in developing systems. Although the joint capture of cellular phenotypes and lineage history enables us to study how important developmental events are regulated, the volume and complexity of the data produced make it difficult to systematically discover new patterns and relationships from this data. We have developed a new way of measuring how cellular phenotypes, such as the length of the cell cycle, differ between cell lineages and applied this approach to the characterization of embryonic development in Caenorhabditis elegans, a microscopic roundworm that has long been used as a model system for studying the regulation of cellular differentiation during embryonic development. Our quantitative and unbiased approach allowed us to describe previously unknown patterns of cell cycle timing between the major lineages of the C. elegans embryo, discover surprising differences between populations of wild type embryos and between embryos in which a panel of genes essential for embryonic development had been perturbed, and provided a quantitative link between cell fate and cell cycle timing patterns that have been widely observed in development but not well understood. These findings highlight the power of our approach and motivate continued investigation of the links between cell cycle timing and cell fate in developing embryos and stem cells. [ABSTRACT FROM AUTHOR]

The γ-ray-emitting galaxy SBS 0846+513 has been classified as a narrow-line Seyfert 1 (NLS1) from its spectroscopy, and on that basis would be thought likely to have a small central black hole hosted in a spiral galaxy. However, very few of the γ-ray NLS1s have high-resolution imaging of their hosts, so it is unknown how the morphology expectation holds up for the γ-emitting class. We have observed this galaxy in the J band with the Large Binocular Telescope's LUCI1 camera and the ARGOS adaptive optics system. We estimate its black hole mass to lie between |$4.2\times 10^7 \le \frac{\rm{\it{ M}}}{\text{M}_\odot } \le 9.7\times 10^7$|⁠ , using the correlation with bulge luminosity, or |$1.9\times 10^7 \le \frac{\rm{\it{ M}}}{\text{M}_\odot } \le 2.4\times 10^7$| using the correlation with Sérsic index. Our favoured estimate is 4.2 × 107 M⊙, putting its mass at the high end of the NLS1 range in general but consistent with others that are γ-ray emitters. These estimates are independent of the broad-line region viewing geometry and avoid any underestimates due to looking down the jet axis. Its host shows evidence of a bulge + disc structure, from the isophote shape and residual structure in the nuclear-subtracted image. This supports the idea that γ-ray NLS1 may be spiral galaxies, like their non-jetted counterparts. [ABSTRACT FROM AUTHOR]

This study explores the impact of bicycle-sharing infrastructure on urban transportation. We estimate a causal effect of the Capital Bikeshare on traffic congestion in the metropolitan Washington, D.C., area. We exploit a unique traffic dataset that is finely defined on a spatial and temporal scale. Our approach examines within-city commuting decisions as opposed to traffic patterns on major thruways. Empirical results suggest that the availability of a bikeshare reduces traffic congestion upwards of 4% within a neighborhood. In addition, we estimate heterogeneous treatment effects using panel quantile regression. Results indicate that the congestion-reducing impact of bikeshares is concentrated in highly congested areas. [ABSTRACT FROM AUTHOR]

We examine the interconnectedness of demand for regionally and locally varying public goods using a residential sorting model. We propose a version of the model that describes household choices at the city (MSA) level and, conditional on city, the neighborhood (census tract) level. We use a two-stage budgeting argument to develop an empirically feasible sorting model that allows us to estimate preferences for regionally varying air quality while accounting for sorting at the local level. Our conceptual and empirical approach nests previous sorting models as special cases, allowing us to assess the importance of accounting for multiple spatial scales in our predictions for the cost of air pollution. Furthermore our preferred specification connects the city and neighborhood sorting margins to the upper and lower elements of a nested logit model, thereby establishing a useful correspondence between two stage budgeting and nested logit estimation. Empirically we find that estimates from a conventional model of sorting across MSAs imply a smaller marginal willingness to pay for air quality than estimates from our proposed model. We discuss how the difference is attributable in part to the omitted variable problems arising when tract level sorting is ignored. [ABSTRACT FROM AUTHOR]

The dichotomy between radio-loud and radio-quiet quasi-stellar objects (QSOs) is not simply one of host morphology. While spiral galaxies almost exclusively host radio-quiet QSOs, ellipticals can host either radio-louds or radio-quiets. We find that a combination of accretion rate and host scale determines which type of QSO a given elliptical galaxy will host. QSOs with high X-ray luminosities (above at 0.5 keV) are mostly radio-loud. But those with low luminosities divide fairly neatly in size (measured by the half-light radius, re). Those larger than about 10 kpc are radio-loud, while smaller ones are radio-quiet. It has recently been found that core and coreless ellipticals are also divided near this limit. This implies that for low-luminosity QSOs, radio-louds are found in core ellipticals, while radio-quiets are in coreless ellipticals and spirals. This segregation also shows up strongly for low-redshift objects and, in general, there is a loss over time of coreless, radio-loud QSOs. Since the presence or absence of a core may be tied to the galactic merger history, we have an evolutionary explanation for the differences between radio-loud and radio-quiet QSOs. [ABSTRACT FROM AUTHOR]

Abstract: We present results from an archival study of 70 medium-redshift QSOs observed with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. The QSOs have magnitudes M V ⩽−23 (total nuclear plus host light) and redshifts 0.06⩽ z ⩽0.46. A close relationship between QSO host and nucleus is found by examining multiple parameters at once. A principal components analysis shows that three nuclear and host properties are related in a kind of fundamental plane: nuclear luminosity and the size and effective surface magnitude of the bulge. Using optical nuclear luminosity, this relationship explains 95.9% of the variance in the overall sample, while 94.9% of the variance is accounted for if we use X-ray nuclear luminosity. The form of this QSO fundamental plane shows similarities to the well-studied fundamental plane of elliptical galaxies, and we examine the possible relationship between them as well as the difficulties involved in establishing this connection. The key to the relationship might lie in the fueling mechanism of the central black hole. [Copyright &y& Elsevier]

Abstract: Lungs harvested for transplantation utilize oxygen after procurement. We investigated the effects of storage solution substrate composition on pulmonary oxidative metabolism and energetics during the preservation interval. Rat lungs were harvested and stored at 10°C in low-potassium dextran (LPD) solution. Groups of lungs were preserved with preservation solution containing 5mM carbon-13 (13C) labeled glucose or increasing concentrations of 13C labeled pyruvate. Additional groups of rat lungs were studied with dichloroacetate (DCA) added to the pyruvate-modified preservation solutions. Oxidative metabolism (measured by 13C-enrichment of glutamate) and adenine nucleotide levels were quantified. Increasing preservation solution pyruvate concentration augmented glutamate 13C-enrichment up to a concentration of 32mM pyruvate. DCA further stimulated oxidative metabolism only at lower concentrations of pyruvate (4 and 8mM). ATP and ADP were not different among groups, but AMP levels were higher in the glucose group. These data suggest that altering the substrate composition of the preservation solution influences lung metabolism during allograft preservation for transplantation. [Copyright &y& Elsevier]

Progressive atrophic rhinitis is an upper respiratory tract disease of pigs caused by toxigenic strains of the bacterium Pasteurella multocida. In this study the effect of P. multocida on the humoral immune response of pigs and mice was investigated. Pigs were given live intranasal challenge with either a toxigenic strain or a non-toxigenic strain of P. multocida, or were given daily intranasal instillation of a cell-free lysate of the toxigenic strain. Mice were given a live intranasal challenge of either a toxigenic or a non-toxigenic strain of P. multocida. All of the animals were immunised with ovalbumin and serum concentrations of anti-ovalbumin antibodies were quantified and compared between different treatment groups and control animals. Intranasal challenge with toxigenic P. multocida caused a significant reduction in the levels of anti-ovalbumin IgG in both species. A similar effect was seen in pigs given a cell-free extract of toxigenic P. multocida. Whilst the mechanism of this suppression is unclear, we surmise that immunomodulation of the host is an important virulence factor for toxigenic P. multocida, and could be an important function of the toxin. This immunomodulatory effect may enhance colonisation of P. multocida aiding horizontal transmission and may predispose to concurrent infection with other potential pathogens. [Copyright &y& Elsevier]

Investigates the effects of alternative reading frame protein p19ARF on the abundance of E2F transcription factor family in cells. Destabiization of E2F1; Reduction in the endogenos stability E2F1 and E2F3; Association of p19ARF with E2F1, E2F2 and E2F3.

This research quantifies the property value benefits of National Wildlife Refuges near urban areas on the eastern coast of the U.S.A. Our approach is made possible through access to confidential U.S. Census data identifying property values surrounding all refuges with high geographic resolution. Results from hedonic property value models suggest that the amenity values of refuges located near urbanized areas are capitalized into the value of homes in very close proximity, averaging $11million per refuge. These capitalized values add directly to the local tax base and are considerable complements to the annual economic value created by the refuge system. [Copyright &y& Elsevier]

We report the discovery of a 'folded' gravitationally lensed image, 'Hamilton's Object', found in a HST image of the field near the active galactic nucleus SDSS J223010.47-081017.8 (which has redshift 0.62). The lensed images are sourced by a galaxy at a spectroscopic redshift of 0.8200 ± 0.0005 and form a fold configuration on a caustic caused by a foreground galaxy cluster at a photometric redshift of 0.526 ± 0.018 seen in the corresponding Pan-STARRS PS1 image and marginally detected as a faint ROSAT All-Sky Survey X-ray source. The lensed images exhibit properties similar to those of other 'folds' where the source galaxy falls very close to or straddles the caustic of a galaxy cluster. The folded images are stretched in a direction roughly orthogonal to the critical curve, but the configuration is that of a tangential cusp. Guided by morphological features, published simulations and similar 'fold' observations in the literature, we identify a third or 'counter'-image, confirmed by spectroscopy. Because the fold-configuration shows highly distinctive surface brightness features, follow-up observations of microlensing or detailed investigations of the individual surface brightness features at higher resolution can further shed light on kpc-scale dark matter properties. We determine the local lens properties at the positions of the multiple images according to the observation-based lens reconstruction of Wagner. The analysis is in accordance with a mass density which hardly varies on an arcsecond scale (6 kpc) over the areas covered by the multiple images. [ABSTRACT FROM AUTHOR]

We present the study of a sample of nine quasi-stellar object fields, with damped Lyman α (DLA) or sub-DLA systems at z ∼ 0.6, observed with the X-Shooter spectrograph at the Very Large Telescope. By suitably positioning the X-Shooter slit based on high spatial resolution images of Hubble Space Telescope/Advanced Camera for Surveys we are able to detect absorbing galaxies in seven out of nine fields (∼78 per cent success rate) at impact parameters from 10 to 30 kpc. In five out of seven fields the absorbing galaxies are confirmed via detection of multiple emission lines at the redshift of DLAs where only one out of five also emits a faint continuum. In two out of these five fields we detect a second galaxy at the DLA redshift. Extinction corrected star formation rates (SFRs) of these DLA galaxies, estimated using their Hα fluxes, are in the range 0.3–6.7 M⊙ yr−1. The emission metallicities of these five DLA galaxies are estimated to be from 0.2 to 0.9 Z⊙. Based on the Voigt profile fits to absorption lines we find the metallicity of the absorbing neutral gas to be in a range of 0.05–0.6 Z⊙. The two remaining DLA galaxies are quiescent galaxies with SFR < 0.4 M⊙ yr−1 (3σ) presenting continuum emission but no emission lines. Using X-Shooter spectrum we estimate i-band absolute magnitude of −19.5 ± 0.2 for both these DLA galaxies that indicates they are sub-L⋆ galaxies. Comparing our results with that of other surveys in the literature we find a possible redshift evolution of the SFR of DLA galaxies. [ABSTRACT FROM AUTHOR]