Cell-Extrinsic Defective Lymphocyte Development in Lmna-/- Mice

Background: Mutations in the LMNA gene, which encodes all A-type lamins, result in a variety of human diseases termed laminopathies. Lmna-/- mice appear normal at birth but become runted as early as 2 weeks of age and develop multiple tissue defects that mimic some aspects of human laminopathies. Lmna-/- mice also display smaller spleens and thymuses. In this study, we investigated whether altered lymphoid organ sizes are correlated with specific defects in lymphocyte development. Principal Findings: Lmna-/- mice displayed severe age-dependent defects in T and B cell development which coincided with runting. Lmna-/- bone marrow reconstituted normal T and B cell development in irradiated wild-type recipients, driving generation of functional and self-MHC restricted CD4 + and CD8 + T cells. Transplantation of Lmna-/- neonatal thymus lobes into syngeneic wild-type recipients resulted in good engraftment of thymic tissue and normal thymocyte development. Conclusions: Collectively, these data demonstrate that the severe defects in lymphocyte development that characterize Lmna-/- mice do not result directly from the loss of A-type lamin function in lymphocytes or thymic stroma. Instead, the immune defects in Lmna-/- mice likely reflect indirect damage, perhaps resulting from prolonged stress due to the striate

Chemical weed control in field corn for 1982 -- part 1 : preplanting incorporated treatments

Harold D. Kerr, Joseph H. Scott, E. J. Peters, L. E. Anderson, O. Hale Fletchall, David Guethle, Zane R. Helsel and Howard Guscar (Department of Agronomy, College of Agriculture)New 1/82/15

Chemical weed control in field corn for 1982, Part 2. Pre-emergence and postemergence

Harold D. Kerr, Joseph H. Scott, E. J. Peters, L. E. Anderson, O. Hale Fletchall, David Guethle, Zane R. Helsel and Howard Guscar (Department of Agronomy, College of Agriculture)Revised 1/82/15

Structural Controls on Shallow Cenozoic Fluid Flow in the Otago Schist, New Zealand

The Otago Schist in the South Island of New Zealand represents an exhumed Mesozoic accretionary prism. Two coastal areas (Akatore Creek and Bruce Rocks) south of Dunedin preserve structural and geochemical evidence for the development of postmetamorphic hydrothermal systems that involved widespread fluid-rock reaction at shallow crustal depths. The Jurassic to Triassic pumpellyite-actinolite (Akatore Creek) to upper greenschist facies (Bruce Rocks) metamorphic fabrics were crosscut by sets of regionally extensive Cretaceous exhumation joints. Many of the joints were subsequently reactivated to form networks of small-displacement (<metres) strike-slip faults containing cemented fault breccias and veins composed of hydrothermal calcite, siderite, and ankerite. Paleostress analysis performed on infrequent fault slickenlines indicates an overall strike-slip paleostress regime and a paleo-σ1 orientation (azimuth 094°) similar to the contemporary σ1 orientation in Otago and Canterbury (azimuth c. 110°-120°). High δ18O values in vein calcite (δ18OVPDB=21 to 28‰), together with the predominance of Type I calcite twins, suggest that vein formation occurred at low temperatures (<200°C) in the shallow crust and was associated with strongly channelized fluid flow along the joint and fault networks. Mass-balance calculations performed on samples from carbonate alteration zones show that significant mobilisation of elements occurred during fluid flow and fluid-rock reaction. Whole-rock and in situ carbonate 87Sr/86Sr data indicate varying degrees of interaction between the hydrothermal fluids and the host rock schists. Fluids were likely derived from the breakdown of metamorphic Ca-rich mineral phases with low 87Rb in the host schists (e.g., epidote or calcite), as well as more radiogenic components such as mica. Overall, the field and geochemical data suggest that shallow fluid flow in the field areas was channelized along foliation surfaces, exhumation joints, and networks of brittle faults, and that these structures controlled the distribution of fluid-rock reactions and hydrothermal veins. The brittle fault networks and associated hydrothermal systems are interpreted to have formed after the onset of Early Miocene compression in the South Island and may represent the manifestation of fracturing and fluid flow associated with reverse reactivation of regional-scale faults such as the nearby Akatore Fault

Predicting Crappie Recruitment in Ohio Reservoirs with Spawning Stock Size, Larval Density, and Chlorophyll Concentrations

Stock-recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from 11 Ohio reservoirs and larvae from 9 reservoirs during 1998-2001. We sampled chlorophyll as an index of reservoir productivity and obtained daily estimates of water elevation to determine the impact of hydrology on recruitment. Akaike's information criterion (AIC) revealed that Ricker and Beverton-Holt stock-recruit models that included chlorophyll best explained the variation in larval density and age-2 recruits. Specifically, spawning stock catch per effort (CPE) and chlorophyll explained 63-64% of the variation in larval density. In turn, larval density and chlorophyll explained 43-49% of the variation in age-2 recruit CPE. Finally, spawning stock CPE and chlorophyll were the best predictors of recruit CPE (i.e., 74-86%). Although larval density and recruitment increased with chlorophyll, neither was related to seasonal water elevation. Also, the AIC generally did not distinguish between Ricker and Beverton-Holt models. From these relationships, we concluded that crappie recruitment can be limited by spawning stock CPE and larval production when spawning stock sizes are low (i.e., CPE , 5 crappies/net-night). At higher levels of spawning stock sizes, spawning stock CPE and recruitment were less clearly related. To predict recruitment in Ohio reservoirs, managers should assess spawning stock CPE with trap nets and estimate chlorophyll concentrations. To increase crappie recruitment in reservoirs where recruitment is consistently poor, managers should use regulations to increase spawning stock size, which, in turn, should increase larval production and recruits to the fishery.This research was funded by Federal Aid in Sport Fish Restoration Project F-69-P, administered jointly by the U.S. Fish and Wildlife Service and Ohio Department of Natural Resources, Division of Wildlife, and the Department of Evolution, Ecology, and Organismal Biology at Ohio State University

Discovery of an intermediate-luminosity red transient in M51 and its likely dust-obscured, infrared-variable progenitor

We present the discovery of an optical transient (OT) in Messier 51, designated M51 OT2019-1 (also ZTF19aadyppr, AT 2019abn, ATLAS19bzl), by the Zwicky Transient Facility (ZTF). The OT rose over 15 days to an observed luminosity of $M_r=-13$ (${\nu}L_{\nu}=9\times10^6~L_{\odot}$), in the luminosity gap between novae and typical supernovae (SNe). Spectra during the outburst show a red continuum, Balmer emission with a velocity width of $\approx400$ km s$^{-1}$, Ca II and [Ca II] emission, and absorption features characteristic of an F-type supergiant. The spectra and multiband light curves are similar to the so-called "SN impostors" and intermediate-luminosity red transients (ILRTs). We directly identify the likely progenitor in archival Spitzer Space Telescope imaging with a $4.5~\mu$m luminosity of $M_{[4.5]}\approx-12.2$ and a $[3.6]-[4.5]$ color redder than 0.74 mag, similar to those of the prototype ILRTs SN 2008S and NGC 300 OT2008-1. Intensive monitoring of M51 with Spitzer further reveals evidence for variability of the progenitor candidate at [4.5] in the years before the OT. The progenitor is not detected in pre-outburst Hubble Space Telescope optical and near-IR images. The optical colors during outburst combined with spectroscopic temperature constraints imply a higher reddening of $E(B-V)\approx0.7$ mag and higher intrinsic luminosity of $M_r\approx-14.9$ (${\nu}L_{\nu}=5.3\times10^7~L_{\odot}$) near peak than seen in previous ILRT candidates. Moreover, the extinction estimate is higher on the rise than on the plateau, suggestive of an extended phase of circumstellar dust destruction. These results, enabled by the early discovery of M51 OT2019-1 and extensive pre-outburst archival coverage, offer new clues about the debated origins of ILRTs and may challenge the hypothesis that they arise from the electron-capture induced collapse of extreme asymptotic giant branch stars.Comment: 21 pages, 5 figures, published in ApJ