18 research outputs found
Hierarchical core-periphery structure in networks
We study core-periphery structure in networks using inference methods based
on a flexible network model that allows for traditional onion-like cores within
cores, but also for hierarchical tree-like structures and more general
non-nested types of structure. We propose an efficient Monte Carlo scheme for
fitting the model to observed networks and report results for a selection of
real-world data sets. Among other things, we observe an empirical distinction
between networks showing traditional core-periphery structure with a dense core
weakly connected to a sparse periphery, and an alternative structure in which
the core is strongly connected both within itself and to the periphery.
Networks vary in whether they are better represented by one type of structure
or the other. We also observe structures that are a hybrid between
core-periphery structure and community structure, in which networks have a set
of non-overlapping cores that correspond roughly to communities, surrounded by
a single undifferentiated periphery. Computer code implementing our methods is
available.Comment: code available: https://github.com/apolanco115/hc
Improving the dimension bound of Hermitian Lifted Codes
In this article we improve the dimension and minimum distance bound of the
the Hermitian Lifted Codes LRCs construction from L\'opez, Malmskog, Matthews,
Pi\~nero and Wooters (L\'opez et. al.) via elementary univariarte polynomial
division. They gave an asymptotic rate estimate of . For the case where
is a power of we improve the rate estimate to using univariate
polynomial division
Intensity of Mystical Experiences Occasioned by 5-MeO-DMT and Comparison With a Prior Psilocybin Study
5-MeO-DMT is a psychoactive substance found in high concentrations in the bufotoxin of the Colorado River Toad (Bufo alvarius). Emerging evidence suggests that vaporized 5-MeO-DMT may occasion mystical experiences of comparable intensity to those occasioned by more widely studied psychedelics such as psilocybin, but no empirical study has tested this hypothesis. Data was obtained from 20 individuals (Mage = 38.9, ± 10.7; male = 55%, Caucasian = 85%) who were administered 5-MeO-DMT as part of a psychospiritual retreat program in Mexico. All participants received 50 mg of inhaled vaporized toad bufotoxin which contains 5-MeO-DMT and completed the Mystical Experience Questionnaire (MEQ30) approximately 4–6 h after their session. Administration of 5-MeO-DMT occasioned strong mystical experiences (MEQ30 Overall Mintensity = 4.17, ± 0.64, range 0–5) and the majority (n = 15, 75%) had “a complete mystical experience” (≥60% on all MEQ30 subscales). Compared to a prior laboratory-based psilocybin study, there were no differences in the intensity of mystical effects between 5-MeO-DMT and a high dose (30 mg/70 kg) of psilocybin, but the intensity of mystical effects was significantly higher in the 5-MeO-DMT sample compared to moderate/high dose (20 mg/70 kg) of psilocybin (MEQ30 Total Score: p = 0.02, d = 0.81). Administration of vaporized 5-MeO-DMT reliably occasioned complete mystical experiences in 75% of individuals and was similar in intensity to high dose psilocybin administered in a laboratory setting. The short duration of action may be advantageous for clinical interventions and for studying mystical-type experiences