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Simple Approaches to Improve Restoration of Coastal Sage Scrub Habitat in Southern California
Rods are less fragile than spheres: Structural relaxation in dense liquids composed of anisotropic particles
We perform extensive molecular dynamics simulations of dense liquids composed
of bidisperse dimer- and ellipse-shaped particles in 2D that interact via
repulsive contact forces. We measure the structural relaxation times obtained
from the long-time decay of the self-part of the intermediate scattering
function for the translational and rotational degrees of freedom (DOF) as a
function of packing fraction \phi, temperature T, and aspect ratio \alpha. We
are able to collapse the \phi and T-dependent structural relaxation times for
disks, and dimers and ellipses over a wide range of \alpha, onto a universal
scaling function {\cal F}_{\pm}(|\phi-\phi_0|,T,\alpha), which is similar to
that employed in previous studies of dense liquids composed of purely repulsive
spherical particles in 3D. {\cal F_{\pm}} for both the translational and
rotational DOF are characterized by the \alpha-dependent scaling exponents \mu
and \delta and packing fraction \phi_0(\alpha) that signals the crossover in
the scaling form {\cal F}_{\pm} from hard-particle dynamics to super-Arrhenius
behavior for each aspect ratio. We find that the fragility at \phi_0,
m(\phi_0), decreases monotonically with increasing aspect ratio for both
ellipses and dimers. Moreover, the results for the slow dynamics of dense
liquids composed of dimer- and ellipse-shaped particles are qualitatively the
same, despite the fact that zero-temperature static packings of dimers are
isostatic, while static packings of ellipses are hypostatic.Comment: 10 pages, 17 figures, and 1 tabl
The κB transcriptional enhancer motif and signal sequences of V(D)J recombination are targets for the zinc finger protein HIVEP3/KRC: a site selection amplification binding study
BACKGROUND: The ZAS family is composed of proteins that regulate transcription via specific gene regulatory elements. The amino-DNA binding domain (ZAS-N) and the carboxyl-DNA binding domain (ZAS-C) of a representative family member, named κB DNA binding and recognition component (KRC), were expressed as fusion proteins and their target DNA sequences were elucidated by site selection amplification binding assays, followed by cloning and DNA sequencing. The fusion proteins-selected DNA sequences were analyzed by the MEME and MAST computer programs to obtain consensus motifs and DNA elements bound by the ZAS domains. RESULTS: Both fusion proteins selected sequences that were similar to the κB motif or the canonical elements of the V(D)J recombination signal sequences (RSS) from a pool of degenerate oligonucleotides. Specifically, the ZAS-N domain selected sequences similar to the canonical RSS nonamer, while ZAS-C domain selected sequences similar to the canonical RSS heptamer. In addition, both KRC fusion proteins selected oligonucleoties with sequences identical to heptamer and nonamer sequences within endogenous RSS. CONCLUSIONS: The RSS are cis-acting DNA motifs which are essential for V(D)J recombination of antigen receptor genes. Due to its specific binding affinity for RSS and κB-like transcription enhancer motifs, we hypothesize that KRC may be involved in the regulation of V(D)J recombination
The 21-SPONGE HI Absorption Survey I: Techniques and Initial Results
We present methods and results from "21-cm Spectral Line Observations of
Neutral Gas with the EVLA" (21-SPONGE), a large survey for Galactic neutral
hydrogen (HI) absorption with the Karl G. Jansky Very Large Array (VLA). With
the upgraded capabilities of the VLA, we reach median root-mean-square (RMS)
noise in optical depth of per
channel for the 31 sources presented here. Upon
completion, 21-SPONGE will be the largest HI absorption survey with this high
sensitivity. We discuss the observations and data reduction strategies, as well
as line fitting techniques. We prove that the VLA bandpass is stable enough to
detect broad, shallow lines associated with warm HI, and show that bandpass
observations can be combined in time to reduce spectral noise. In combination
with matching HI emission profiles from the Arecibo Observatory (
angular resolution), we estimate excitation (or spin) temperatures ()
and column densities for Gaussian components fitted to sightlines along which
we detect HI absorption (30/31). We measure temperatures up to for individual lines, showing that we can probe the
thermally unstable interstellar medium (ISM) directly. However, we detect fewer
of these thermally unstable components than expected from previous
observational studies. We probe a wide range in column density between
and for individual HI clouds. In addition,
we reproduce the trend between cold gas fraction and average found by
synthetic observations of a hydrodynamic ISM simulation by Kim et al. (2014).
Finally, we investigate methods for estimating HI and discuss their
biases.Comment: Accepted for publication in ApJ; 24 pages, 14 figure
The Large Zinc Finger Protein ZAS3 Is a Critical Modulator of Osteoclastogenesis
Mice deficient in the large zinc finger protein, ZAS3, show postnatal increase in bone mass suggesting that ZAS3 is critical in the regulation of bone homeostasis. Although ZAS3 has been shown to inhibit osteoblast differentiation, its role on osteoclastogenesis has not been determined. In this report we demonstrated the role of ZAS3 in bone resorption by examining the signaling mechanisms involved in osteoclastogenesis.Comparison of adult wild-type and ZAS3 knockout (ZAS3-/-) mice showed that ZAS3 deficiency led to thicker bones that are more resistant to mechanical fracture. Additionally, ZAS3-/- bones showed fewer osteoclasts and inefficient M-CSF/sRANKL-mediated osteoclastogenesis ex vivo. Utilizing RAW 264.7 pre-osteoclasts, we demonstrated that overexpression of ZAS3 promoted osteoclastogenesis and the expression of crucial osteoclastic molecules, including phospho-p38, c-Jun, NFATc1, TRAP and CTSK. Contrarily, ZAS3 silencing by siRNA inhibited osteoclastogenesis. Co-immunoprecipitation experiments demonstrated that ZAS3 associated with TRAF6, the major receptor associated molecule in RANK signaling. Furthermore, EMSA suggested that nuclear ZAS3 could regulate transcription by binding to gene regulatory elements.Collectively, the data suggested a novel role of ZAS3 as a positive regulator of osteoclast differentiation. ZAS3 deficiency caused increased bone mass, at least in part due to decreased osteoclast formation and bone resorption. These functions of ZAS3 were mediated via activation of multiple intracellular targets. In the cytoplasmic compartment, ZAS3 associated with TRAF6 to control NF-kB and MAP kinase signaling cascades. Nuclear ZAS3 acted as a transcriptional regulator for osteoclast-associated genes. Additionally, ZAS3 activated NFATc1 required for the integration of RANK signaling in the terminal differentiation of osteoclasts. Thus, ZAS3 was a crucial molecule in osteoclast differentiation, which might potentially serve as a target in the design of therapeutic interventions for the treatment of bone diseases related to increased osteoclast activity such as postmenopausal osteoporosis, Paget's disease, and rheumatoid arthritis
Managing Soybean Insects
36 pp., 3 tables, 18 illustrations, 28 photosThis publication details integrated pest management principles for managing soybean insects. Topics include variety selection, inspecting fields for insects and damage, soybean insect pests, and insecticide application methods. A table lists products registered for controlling soybean insects
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