28 research outputs found
Effects of Baryonic Feedback on the Cosmic Web
We study the effect of baryons on the cosmic web -- halos, filaments, walls,
and voids. To do so, we apply a modified version of NEXUS, a cosmic web
morphological analysis algorithm, to the IllustrisTNG simulations. We find that
halos lose more than of their mass due to baryons, mostly to filaments
and a small portion to walls and voids. However, the mass transfer does not
significantly shift the boundaries of structures, leaving the volume fractions
of the cosmic structures largely unaffected. We quantify the effects of
baryonic feedback on the power spectrum and the probability density function
(PDF) of the density field for individual cosmic structures. For the power
spectrum, most suppression due to feedback can be accounted for by including
halos, without considering other cosmic structures.
However, when examining the PDF of the density field, we find nearly
suppression of the emptiest regions and -level effects (boost or
suppression) in the remaining regions of filaments, walls, and voids. Our
results indicate the importance of modeling the effects of baryons in the whole
cosmic web, not just halos, for cosmological analysis beyond two-point
statistics or field-based inferences.Comment: 7 pages, 4 figure
Mission Operations and Navigation Toolkit Environment
MONTE (Mission Operations and Navigation Toolkit Environment) Release 7.3 is an extensible software system designed to support trajectory and navigation analysis/design for space missions. MONTE is intended to replace the current navigation and trajectory analysis software systems, which, at the time of this reporting, are used by JPL's Navigation and Mission Design section. The software provides an integrated, simplified, and flexible system that can be easily maintained to serve the needs of future missions in need of navigation services
The asparagus genome sheds light on the origin and evolution of a young Y chromosome
Several models have been proposed to explain the emergence of sex chromosomes. Here, through comparative genomics and mutant analysis, Harkess et al. show that linked but separate genes on the Y chromosome are responsible for sex determination in Asparagus, supporting a two-gene model for sex chromosome evolution
The Gravity Collective: A Search for the Electromagnetic Counterpart to the Neutron Star-Black Hole Merger GW190814
We present optical follow-up imaging obtained with the Katzman Automatic
Imaging Telescope, Las Cumbres Observatory Global Telescope Network, Nickel
Telescope, Swope Telescope, and Thacher Telescope of the LIGO/Virgo
gravitational wave (GW) signal from the neutron star-black hole (NSBH) merger
GW190814. We searched the GW190814 localization region (19 deg for the
90th percentile best localization), covering a total of 51 deg and 94.6%
of the two-dimensional localization region. Analyzing the properties of 189
transients that we consider as candidate counterparts to the NSBH merger,
including their localizations, discovery times from merger, optical spectra,
likely host-galaxy redshifts, and photometric evolution, we conclude that none
of these objects are likely to be associated with GW190814. Based on this
finding, we consider the likely optical properties of an electromagnetic
counterpart to GW190814, including possible kilonovae and short gamma-ray burst
afterglows. Using the joint limits from our follow-up imaging, we conclude that
a counterpart with an -band decline rate of 0.68 mag day, similar to
the kilonova AT 2017gfo, could peak at an absolute magnitude of at most
mag (50% confidence). Our data are not constraining for ''red'' kilonovae and
rule out ''blue'' kilonovae with (30% confidence). We
strongly rule out all known types of short gamma-ray burst afterglows with
viewing angles 17 assuming an initial jet opening angle of
and explosion energies and circumburst densities similar to
afterglows explored in the literature. Finally, we explore the possibility that
GW190814 merged in the disk of an active galactic nucleus, of which we find
four in the localization region, but we do not find any candidate counterparts
among these sources.Comment: 86 pages, 9 figure
TIGIT is a key inhibitory checkpoint receptor in lymphoma
Background PD-1 checkpoint blockade therapy (CBT) has greatly benefited patients with select solid tumors and lymphomas but has limited efficacy against diffuse large B-cell lymphoma (DLBCL). Because numerous inhibitory checkpoint receptors have been implicated in driving tumor-specific T cell dysfunction, we hypothesized that combinatorial CBT would enhance the activity of anti-PD-1-based therapy in DLBCL. T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) is a coinhibitory receptor expressed on dysfunctional tumor-infiltrating T cells, and TIGIT blockade has demonstrated encouraging activity in combination with PD-1 blockade in murine tumor models and in clinical studies. However, the degree to which TIGIT mediates T cell dysfunction in DLBCL has not been fully explored.Results Here, we demonstrate that TIGIT is broadly expressed on lymphoma-infiltrating T cells (LITs) across a variety of human lymphomas and is frequently coexpressed with PD-1. TIGIT expression is particularly common on LITs in DLBCL, where TIGIT+ LITs often form distinct cellular communities and exhibit significant contact with malignant B cells. TIGIT+/PD-1+ LITs from human DLBCL and murine lymphomas exhibit hypofunctional cytokine production on ex vivo restimulation. In mice with established, syngeneic A20 B-cell lymphomas, TIGIT or PD-1 mono-blockade leads to modest delays in tumor outgrowth, whereas PD-1 and TIGIT co-blockade results in complete rejection of A20 lymphomas in most mice and significantly prolongs survival compared with mice treated with monoblockade therapy.Conclusions These results provide rationale for clinical investigation of TIGIT and PD-1 blockade in lymphomas, including DLBCL
Retrospective Cohort Study of Methotrexate Use in the Treatment of Pediatric Crohn\u27s Disease
BACKGROUND:
Methotrexate (MTX) use as an alternative to thiopurines in the treatment of Crohn\u27s disease (CD) in children is increasing. This study was undertaken to assess safety and efficacy of MTX in children with CD. METHODS:
Patients treated with MTX with a minimum of 1-year follow-up were identified in the Pediatric IBD Collaborative Research Group Registry, a prospective inception cohort study started in 2002. The clinical efficacy and safety of MTX were analyzed retrospectively. RESULTS:
Two hundred ninety patients treated with MTX were identified. One hundred seventy-two patients received at least 3 months of MTX without thiopurine or biologicals and had ≥1 year of follow-up. Eighty-one of 172 patients (47%) received MTX as first immunomodulator (IMM), of which 22 (27%) achieved ≥12 months of sustained clinical remission without surgery, thiopurine, biologicals, or corticosteroids. Those receiving MTX as second IMM achieved similar remission rate (35%, P = not significant). Fourteen percent received MTX as first IMM in 2002 and 60% in 2010 (P = 0.005). Disease location did not affect outcomes. MTX doses were equivalent in both groups. Fifteen percent of patients developed an alanine aminotransferase \u3e60 international units/liter and 12% developed a white blood cell \u3c4000 cells per microliter while on MTX. Only 4% of these discontinued MTX completely. A small group of 6 centers, which contributed only about one-third of patients with CD in the registry, contributed nearly two-thirds of the patients receiving MTX (P \u3c 0.001). CONCLUSIONS:
MTX use as first choice IMM is increasing in pediatric CD. MTX provided sustained clinical remission in nearly one-third of patients with minimal toxicity. There is large center-to-center variability in its use
Retrospective Cohort Study of Methotrexate Use in the Treatment of Pediatric Crohn\u27s Disease
BACKGROUND:
Methotrexate (MTX) use as an alternative to thiopurines in the treatment of Crohn\u27s disease (CD) in children is increasing. This study was undertaken to assess safety and efficacy of MTX in children with CD. METHODS:
Patients treated with MTX with a minimum of 1-year follow-up were identified in the Pediatric IBD Collaborative Research Group Registry, a prospective inception cohort study started in 2002. The clinical efficacy and safety of MTX were analyzed retrospectively. RESULTS:
Two hundred ninety patients treated with MTX were identified. One hundred seventy-two patients received at least 3 months of MTX without thiopurine or biologicals and had ≥1 year of follow-up. Eighty-one of 172 patients (47%) received MTX as first immunomodulator (IMM), of which 22 (27%) achieved ≥12 months of sustained clinical remission without surgery, thiopurine, biologicals, or corticosteroids. Those receiving MTX as second IMM achieved similar remission rate (35%, P = not significant). Fourteen percent received MTX as first IMM in 2002 and 60% in 2010 (P = 0.005). Disease location did not affect outcomes. MTX doses were equivalent in both groups. Fifteen percent of patients developed an alanine aminotransferase \u3e60 international units/liter and 12% developed a white blood cell4% of these discontinued MTX completely. A small group of 6 centers, which contributed only about one-third of patients with CD in the registry, contributed nearly two-thirds of the patients receiving MTX (P \u3c 0.001). CONCLUSIONS:
MTX use as first choice IMM is increasing in pediatric CD. MTX provided sustained clinical remission in nearly one-third of patients with minimal toxicity. There is large center-to-center variability in its use