We perform a spectroscopic analysis of 492 450 galaxy spectra from the first two years of observations of the Sloan Digital Sky Survey (SDSS) III/Baryonic Oscillation Spectroscopic Survey (BOSS) ...collaboration. This data set has been released in the ninth SDSS data release, the first public data release of BOSS spectra. We show that the typical signal-to-noise ratio of BOSS spectra, despite being low, is sufficient to measure stellar velocity dispersion and emission line fluxes for individual objects. We show that the typical velocity dispersion of a BOSS galaxy is ∼240 km s−1. The typical error in the velocity dispersion measurement is 14 per cent, and 93 per cent of BOSS galaxies have velocity dispersions with an accuracy of better than 30 per cent. The distribution in velocity dispersion is redshift independent between redshifts 0.15 and 0.7, which reflects the survey design targeting massive galaxies with an approximately uniform mass distribution in this redshift interval. We show that emission lines can be measured on BOSS spectra. However, the majority of BOSS galaxies lack detectable emission lines, as is to be expected because of the target selection design towards massive galaxies. We analyse the emission line properties and present diagnostic diagrams using the emission lines O ii, Hβ, O iii, Hα and N ii (detected in about 4 per cent of the galaxies) to separate star-forming objects and active galactic nuclei (AGN). We show that the emission line properties are strongly redshift dependent and that there is a clear correlation between observed frame colours and emission line properties. Within in the low-z sample (LOWZ) around 0.15 < z < 0.3, half of the emission line galaxies have low-ionization nuclear emission-line region (LINER)-like emission line ratios, followed by Seyfert-AGN-dominated spectra, and only a small fraction of a few per cent are purely star-forming galaxies. AGN and LINER-like objects, instead, are less prevalent in the high-z sample (CMASS) around 0.4 < z < 0.7, where more than half of the emission line objects are star forming. This is a pure selection effect caused by the non-detection of weak Hβ emission lines in the BOSS spectra. Finally, we show that star-forming, AGN and emission line free galaxies are well separated in the g − r versus r − i target selection diagram.
Soft tissue sarcomas are pleiotropic tumors of mesenchymal cell origin. These tumors are rare in humans but common in veterinary practice, where they comprise up to 15% of canine skin and ...subcutaneous cancers. Because they present similar morphologies, primary sites, and growth characteristics, they are treated similarly, generally by surgical resection followed by radiation therapy. Previous studies have examined a variety of genetic changes as potential drivers of tumorigenesis and progression in soft tissue sarcomas as well as their use as markers for soft tissue sarcoma subtypes. However, few studies employing next generation sequencing approaches have been published. Here, we have examined gene expression patterns in canine soft tissue sarcomas using RNA-seq analysis of samples obtained from archived formalin-fixed and paraffin-embedded tumors. We provide a computational framework for using resulting data to categorize tumors, perform cross species comparisons and identify genetic changes associated with tumorigenesis. Functional overrepresentation analysis of differentially expressed genes further implicate both common and tumor-type specific transcription factors as potential mediators of tumorigenesis and aggression. Implications for tumor-type specific therapies are discussed. Our results illustrate the potential utility of this approach for the discovery of new therapeutic approaches to the management of canine soft tissue sarcomas and support the view that both common and tumor-type specific mechanisms drive the development of these tumors.
Ischemia and subsequent reperfusion (IR) produces injury to brain, eye and other tissues, contributing to the progression of important clinical pathologies. The response of cells to IR involves ...activation of several signaling pathways including those activating hypoxia and heat shock responsive transcription factors. However, specific roles of these responses in limiting cell damage and preventing cell death after IR have not been fully elucidated. Here, we have examined the role of heat shock factor 1 (HSF1) in the response of zebrafish embryos to hypoxia and subsequent return to normoxic conditions (HR) as a model for IR. Heat shock preconditioning elevated heat shock protein expression and protected zebrafish embryo eye and brain tissues against HR-induced apoptosis. These effects were inhibited by translational suppression of HSF1 expression. Reduced expression of HSF1 also increased cell death in brain and eye tissues of embryos subjected to hypoxia and reperfusion without prior heat shock. Surprisingly, reduced expression of HSF1 had only a modest effect on hypoxia-induced expression of Hsp70 and no effect on hypoxia-induced expression of Hsp27. These results establish the zebrafish embryo as a model for the study of ischemic injury in the brain and eye and reveal a critical role for HSF1 in the response of these tissues to HR. Our results also uncouple the role of HSF1 expression from that of Hsp27, a well characterized heat shock protein considered essential for cell survival after hypoxia. Alternative roles for HSF1 are considered.
Mammalian small heat shock proteins (sHSP) are abundant in muscles and are implicated in both muscle function and myopathies. Recently a new sHSP, HSP22 (HSPB8, H11), was identified in the human ...heart by its interaction with HSP27 (HSPB1). Using phylogenetic analysis we show that HSP22 is a true member of the sHSP superfamily. sHSPs interact with each other and form homo- and hetero-oligomeric complexes. The function of these complexes is poorly understood. Using gel filtration HPLC, the yeast two-hybrid method, immunoprecipitation, cross-linking, and fluorescence resonance energy transfer microscopy, we report that (i) HSP22 forms high molecular mass complexes in the heart, (ii) HSP22 interacts with itself, cvHSP (HSPB7), MKBP (HSPB2) and HSP27, and (iii) HSP22 has two binding domains (N- and C-terminal) that are specific for different binding partners. HSP22 homo-dimers are formed through N-N and N-C interactions, and HSP22-cvHSP hetero-dimers through C-C interaction. HSP22-MKBP and HSP22-HSP27 hetero-dimers involve the N and C termini of HSP22 and HSP27, respectively, but appear to require full-length protein as a binding partner.
This impressive collection joins the recent outpouring of exciting new work on American politics and political actors in the mid-nineteenth century. For several generations, much of the scholarship ...on the political history of the period from 1840 to 1877 has carried a theme of failure; after all, politicians in the antebellum years failed to prevent war, and those of the Civil War and Reconstruction failed to take advantage of opportunities to remake the nation. Moving beyond these older debates, the essays in this volume ask new questions about mid-nineteenth-century American politics and politicians.
InA Political Nation,the contributors address the dynamics of political parties and factions, illuminate the presence of consensus and conflict in American political life, and analyze elections, voters, and issues. In addition to examining the structures of the United States Congress, state and local governments, and other political organizations, this collection emphasizes political leaders-those who made policy, ran for office, influenced elections, and helped to shape American life from the early years of the Second Party System to the turbulent period of Reconstruction.
The book moves chronologically, beginning with an antebellum focus on how political actors behaved within their cultural surroundings. The authors then use the critical role of language, rhetoric, and ideology in mid-nineteenth-century political culture as a lens through which to reevaluate the secession crisis. The collection closes with an examination of cultural and institutional influences on politicians in the Civil War and Reconstruction years. Stressing the role of federalism in understanding American political behavior,A Political Nationunderscores the vitality of scholarship on mid-nineteenth-century American politics.
Contributors:Erik B. Alexander, University of Tennessee, Knoxville · Jean Harvey Baker, Goucher College · William J. Cooper, Louisiana State University · Daniel W. Crofts, The College of New Jersey · William W. Freehling, Virginia Foundation for the Humanities · Gary W. Gallagher, University of Virginia · Sean Nalty, University of Virginia · Mark E. Neely Jr., Pennsylvania State University · Rachel A. Shelden, Georgia College and State University · Brooks D. Simpson, Arizona State University · J. Mills Thornton, University of Michigan, Ann Arbor
Traditional portrayals of politicians in antebellum Washington, D.C., describe a violent and divisive society, full of angry debates and violent duels, a microcosm of the building animosity ...throughout the country. Yet, inWashington Brotherhood, Rachel Shelden paints a more nuanced portrait of Washington as a less fractious city with a vibrant social and cultural life. Politicians from different parties and sections of the country interacted in a variety of day-to-day activities outside traditional political spaces and came to know one another on a personal level. Shelden shows that this engagement by figures such as Stephen Douglas, John Crittenden, Abraham Lincoln, and Alexander Stephens had important consequences for how lawmakers dealt with the sectional disputes that bedeviled the country during the 1840s and 1850s--particularly disputes involving slavery in the territories.Shelden uses primary documents--from housing records to personal diaries--to reveal the ways in which this political sociability influenced how laws were made in the antebellum era. Ultimately, this Washington "bubble" explains why so many of these men were unprepared for secession and war when the winter of 1860-61 arrived.
Individuals with systemic lupus erythematosus show evidence of a significant increase in monocyte apoptosis. This process is mediated, at least in part, by an autoreactive T cell subset that kills ...autologous monocytes in the absence of nominal Ag. We have investigated the apoptotic pathways involved in this T cell-mediated process. Expression of the apoptotic ligands TRAIL, TNF-like weak inducer of apoptosis (TWEAK), and Fas ligand on lupus T cells was determined, and the role of these molecules in the monocyte apoptotic response was examined. We report that these apoptotic ligands mediate the autologous monocyte death induced by lupus T cells and that this cytotoxicity is associated with increased expression of these molecules on activated T cells, rather than with an increased susceptibility of lupus monocytes to apoptosis induced by these ligands. These results define novel mechanisms that contribute to increased monocyte apoptosis characterizing patients with lupus. We propose that this mechanism could provide a source of potentially antigenic material for the autoimmune response and interfere with normal clearing mechanisms.
Cardiac and skeletal myosin assembled in the muscle lattice power contraction by transducing ATP free energy into the mechanical work of moving actin. Myosin catalytic/lever-arm domains comprise the ...transduction/mechanical coupling machinery that move actin by lever-arm rotation. In vivo, myosin is crowded and constrained by the fiber lattice as side chains are mutated and otherwise modified under normal, diseased, or aging conditions that collectively define the native myosin environment. Single-myosin detection uniquely defines bottom-up characterization of myosin functionality. The marriage of in vivo and single-myosin detection to study zebrafish embryo models of human muscle disease is a multiscaled technology that allows one-to-one registration of a selected myosin molecular alteration with muscle filament-sarcomere-cell-fiber-tissue-organ- and organism level phenotypes. In vivo single-myosin lever-arm orientation was observed at superresolution using a photoactivatable-green-fluorescent-protein (PAGFP)-tagged myosin light chain expressed in zebrafish skeletal muscle. By simultaneous observation of multiphoton excitation fluorescence emission and second harmonic generation from myosin, we demonstrated tag specificity for the lever arm. Single-molecule detection used highly inclined parallel beam illumination and was verified by quantized photoactivation and photobleaching. Single-molecule emission patterns from relaxed muscle in vivo provided extensive superresolved dipole orientation constraints that were modeled using docking scenarios generated for the myosin (S1) and GFP crystal structures. The dipole orientation data provided sufficient constraints to estimate S1/GFP coordination. The S1/GFP coordination in vivo is rigid and the lever-arm orientation distribution is well-ordered in relaxed muscle. For comparison, single myosins in relaxed permeabilized porcine papillary muscle fibers indicated slightly differently oriented lever arms and rigid S1/GFP coordination. Lever arms in both muscles indicated one preferred spherical polar orientation and widely distributed azimuthal orientations relative to the fiber symmetry axis. Cardiac myosin is more radially displaced from the fiber axis. Probe rigidity implies the PAGFP tag reliably indicates cross-bridge orientation in situ and in vivo.
Activation of the LH receptor (LHR) on preovulatory granulosa cells stimulates the cAMP/protein kinase A (PKA) pathway to regulate expression of genes required for ovulation and luteinization. LHR ...signaling also initiates rearrangement of the actin cytoskeleton. Because disruption of the actin cytoskeleton has been causally linked to steroidogenesis in various cell models, we sought to identify the cellular mechanisms that may modulate reorganization of the actin cytoskeleton and to determine whether cytoskeletal reorganization is required for steroidogenesis. Herein we report that LHR signaling in preovulatory granulosa cells promotes rapid dephosphorylation of the actin-depolymerizing factor cofilin at Ser3 that is dependent on PKA. The LHR-stimulated dephosphorylation of cofilin(Ser3) switches on cofilin activity to bind actin filaments and enhance their dynamics. Basal phosphorylation of cofilin(Ser3) is mediated by active/GTP-bound Rho and downstream protein kinases; LHR signaling promotes a decrease in active/GTP-bound Rho by a PKA-dependent mechanism. LHR-dependent Rho inactivation and subsequent activation of cofilin does not involve ERK, epidermal growth factor receptor, or phosphatidylinositol 3-kinase pathways downstream of PKA. To understand the biological significance of cofilin activation, preovulatory granulosa cells were transduced with a mutant cofilin adenoviral vector in which Ser3 was mutated to Glu (S-E cofilin). Inactive S-E cofilin abolished LHR-mediated reorganization of the actin cytoskeleton and caused a 70% decrease in LHR-stimulated progesterone that is obligatory for ovulation. Taken together, these results show that LHR signaling via PKA activates a cofilin-regulated rearrangement of the actin cytoskeleton and that active cofilin is required to initiate progesterone secretion by preovulatory granulosa cells.
Activation of the LH receptor in preovulatory granulosa cells promotes the PKA-dependent activation of cofilin that is required to initiate progesterone secretion.
We report the discovery in the Sloan Digital Sky Survey (SDSS) and the SDSS-III Baryon Oscillation Spectroscopic Survey of 17 broad absorption line (BAL) quasars with high-ionization troughs that ...include absorption redshifted relative to the quasar rest frame. The redshifted troughs extend to velocities up to v 12 000 km s−1 and the trough widths exceed 3000 km s−1 in all but one case. Approximately 1 in 1000 BAL quasars with blueshifted C iv absorption also has redshifted C iv absorption; objects with C iv absorption present only at redshifted velocities are roughly four times rarer. In more than half of our objects, redshifted absorption is seen in C ii or Al iii as well as C iv, making low-ionization absorption at least 10 times more common among BAL quasars with redshifted troughs than among standard BAL quasars. However, the C iv absorption equivalent widths in our objects are on average smaller than those of standard BAL quasars with low-ionization absorption.
We consider several possible ways of generating redshifted absorption. The two most likely possibilities may be at work simultaneously, in the same objects or in different ones. Rotationally dominated outflows seen against a quasar's extended continuum source can produce redshifted and blueshifted absorption, but variability consistent with this scenario is seen in only one of the four objects with multiple spectra. The infall of relatively dense and low-ionization gas to radii as small as 400 Schwarzschild radii can in principle explain the observed range of trough profiles, but current models do not easily explain the origin and survival of such gas. Whatever the origin(s) of the absorbing gas in these objects, it must be located at small radii to explain its large redshifted velocities, and thus offers a novel probe of the inner regions of quasars.
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