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Comparisons of Animal “Smarts” Using the First Four Stages of the Model of Hierarchical Complexity
The Model of Hierarchical Complexity is a behavioral model of development and evolution of the complexity of behavior. It is based on task analysis. Tasks are ordered in terms of their hierarchical complexity, which is an ordinal scale that measures difficulty. The hierarchical difficulty of tasks is categorized as the order of hierarchical complexity. Successful performance on a task is called the behavioral stage. This model can be applied to non-human animals, and humans. Using data from some of the simplest animals and also somewhat more complex ones, this analysis describes the four lowest behavioral stages and illustrate them using the behaviors of a range of simple organisms. For example, Stage 1 tasks, and performance on them, are addressed with automatic unconditioned responses. Behavior at this Stage includes sensing, tropisms, habituation and, other automatic behaviors. Single cell organisms operate at this Stage. Stage 2 tasks include these earlier behaviors, but also include respondent conditioning but not operant conditioning. Animals such as some simple invertebrates have shown respondent conditioning, but not operant conditioning. Stage 3 tasks coordinate three instances of these earlier tasks to make possible operant conditioning. These stage 3 performances are similar to those of some invertebrates and also insects. Stage 4 tasks organisms coordinate 2 or more circular sensory-motor task actions into a superordinate “concept”. This explanation of the early stages of the Model of Hierarchical Complexity may help future research in animal behavior, and comparative psychology.
On Factorization of a Special type of Vandermonde Rhotrix
Vandermonde matrices have important role in many branches of applied mathematics such as combinatorics, coding theory and cryptography. Some authors discuss Vandermonde rhotrices in the literature for its mathematical enrichment. Here, we introduce a special type of Vandermonde rhotrix and obtain its LR factorization, namely left and right triangular factorization which is further used to obtain the inverse of the rhotrix
Infrared emission from kilonovae: the case of the nearby short hard burst GRB 160821B
We present constraints on Ks-band emission from one of the nearest short hard
gamma-ray bursts, GRB 160821B, at z=0.16, at three epochs. We detect a reddened
relativistic afterglow from the jetted emission in the first epoch but do not
detect any excess kilonova emission in the second two epochs. We compare upper
limits obtained with Keck I/MOSFIRE to multi-dimensional radiative transfer
models of kilonovae, that employ composition-dependent nuclear heating and LTE
opacities of heavy elements. We discuss eight models that combine toroidal
dynamical ejecta and two types of wind and one model with dynamical ejecta
only. We also discuss simple, empirical scaling laws of predicted emission as a
function of ejecta mass and ejecta velocity. Our limits for GRB 160821B
constrain the ejecta mass to be lower than 0.03 Msun for velocities greater
than 0.1c. At the distance sensitivity range of advanced LIGO, similar
ground-based observations would be sufficiently sensitive to the full range of
predicted model emission including models with only dynamical ejecta. The color
evolution of these models shows that I-K color spans 7--16 mag, which suggests
that even relatively shallow infrared searches for kilonovae could be as
constraining as optical searches.Comment: Accepted for Publication in Astrophysical Journal Letter
Detection of a-to-i rna editing in sars-cov-2
ADAR1-mediated deamination of adenosines in long double-stranded RNAs plays an important role in modulating the innate immune response. However, recent investigations based on metatranscriptomic samples of COVID-19 patients and SARS-COV-2-infected Vero cells have recovered contrasting findings. Using RNAseq data from time course experiments of infected human cell lines and transcriptome data from Vero cells and clinical samples, we prove that A-to-G changes observed in SARS-COV-2 genomes represent genuine RNA editing events, likely mediated by ADAR1. While the A-to-I editing rate is generally low, changes are distributed along the entire viral genome, are overrepresented in exonic regions, and are (in the majority of cases) nonsynonymous. The impact of RNA editing on virus–host interactions could be relevant to identify potential targets for therapeutic interventions
Tpz1TPP1 SUMOylation reveals evolutionary conservation of SUMO-dependent Stn1 telomere association
Elongation of the telomeric overhang by telomerase is counteracted by synthesis of the complementary strand by the CST complex, CTC1(Cdc13)/Stn1/Ten1. Interaction of budding yeast Stn1 with overhang-binding Cdc13 is increased by Cdc13
SUMOylation. Human and fission yeast CST instead interact with overhang-binding TPP1/POT1. We show that the fission yeast TPP1 ortholog, Tpz1, is SUMOylated. Tpz1 SUMOylation restricts telomere elongation and promotes Stn1/Ten1 telomere association,and a SUMO-Tpz1 fusion protein has increased affinity for Stn1. Our data suggest that SUMO inhibits telomerase through stimulation of Stn1/Ten1 action by Tpz1, highlighting the evolutionary conservation of the regulation of CST function by SUMOylation
On Circulant-Like Rhotrices over Finite Fields
Circulant matrices over finite fields are widely used in cryptographic hash functions, Lattice based cryptographic functions and Advanced Encryption Standard (AES). Maximum distance separable codes over finite field GF2 have vital a role for error control in both digital communication and storage systems whereas maximum distance separable matrices over finite field GF2 are used in block ciphers due to their properties of diffusion. Rhotrices are represented in the form of coupled matrices. In the present paper, we discuss the circulant- like rhotrices and then construct the maximum distance separable rhotrices over finite fields
On factorization of a special type of vandermonde rhotrix
Vandermonde matrices have important role in many branches of applied mathematics such as combinatorics, coding theory and cryptography. Some authors discuss the Vandermonde rhotrices in the literature for its mathematical enrichment. Here, we introduce a special type of Vandermonde rhotrix and obtain its LR factorization namely left and right triangular factorization, which is further used to obtain the inverse of the rhotrix
An Optical and Infrared Time-Domain Study of the Supergiant Fast X-ray Transient Candidate IC 10 X-2
We present an optical and infrared (IR) study of IC 10 X-2, a high-mass X-ray
binary in the galaxy IC 10. Previous optical and X-ray studies suggest X-2 is a
Supergiant Fast X-ray Transient: a large-amplitude (factor of 100),
short-duration (hours to weeks) X-ray outburst on 2010 May 21. We analyze R-
and g-band light curves of X-2 from the intermediate Palomar Transient Factory
taken between 2013 July 15 and 2017 Feb 14 show high-amplitude ( 1
mag), short-duration ( d) flares and dips ( 0.5 mag).
Near-IR spectroscopy of X-2 from Palomar/TripleSpec show He I,
Paschen-, and Paschen- emission lines with similar shapes and
amplitudes as those of luminous blue variables (LBVs) and LBV candidates
(LBVc). Mid-IR colors and magnitudes from Spitzer/IRAC photometry of X-2
resemble those of known LBV/LBVcs. We suggest that the stellar companion in X-2
is an LBV/LBVc and discuss possible origins of the optical flares. Dips in the
optical light curve are indicative of eclipses from optically thick clumps
formed in the winds of the stellar counterpart. Given the constraints on the
flare duration ( d) and the time between flares ( d),
we estimate the clump volume filling factor in the stellar winds, , to be
, which overlaps with values measured from massive star
winds. In X-2, we interpret the origin of the optical flares as the accretion
of clumps formed in the winds of an LBV/LBVc onto the compact object.Comment: 15 pages, 4 figures. Submitted to ApJ on Sep 26 201
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