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Reply to: fMRI replicability depends upon sufficient individual-level data.
Theoretical flow regime diagrams for the AGCE
The major criterion for the design of the Atmospheric General Circulation Experiment is that it be possible to realize strong baroclinic instability in the apparatus. A spherical annulus configuration which allows only steady basic state flows was chosen for the first set of stability analyses. Baroclinic instability was found for this configuration and few results suggest a regime diagram very different from the cylindrical annulus regime diagram
Environmental contamination of the Yupik people of St. Lawrence Island, Alaska
Persistent, bioaccumulative, and toxic chemicals that originate primarily from industrial areas in temperate climates are ubiquitous in the Arctic. The people of St. Lawrence Island, Alaska, have never directly benefited from the industries that made and profited from use of these chemicals. This striking example of environmental injustice is discussed
Comments on the classification of the finite subgroups of SU(3)
Many finite subgroups of SU(3) are commonly used in particle physics. The
classification of the finite subgroups of SU(3) began with the work of H.F.
Blichfeldt at the beginning of the 20th century. In Blichfeldt's work the two
series (C) and (D) of finite subgroups of SU(3) are defined. While the group
series Delta(3n^2) and Delta(6n^2) (which are subseries of (C) and (D),
respectively) have been intensively studied, there is not much knowledge about
the group series (C) and (D). In this work we will show that (C) and (D) have
the structures (C) \cong (Z_m x Z_m') \rtimes Z_3 and (D) \cong (Z_n x Z_n')
\rtimes S_3, respectively. Furthermore we will show that, while the (C)-groups
can be interpreted as irreducible representations of Delta(3n^2), the
(D)-groups can in general not be interpreted as irreducible representations of
Delta(6n^2).Comment: 15 pages, no figures, typos corrected, clarifications and references
added, proofs revise
EVAPORATION OF QUARK DROPS DURING THE COSMOLOGICAL Q-H TRANSITION
We have carried out a study of the hydrodynamics of disconnected quark
regions during the final stages of the cosmological quark-hadron transition. A
set of relativistic Lagrangian equations is presented for following the
evaporation of a single quark drop and results from the numerical solution of
this are discussed. A self-similar solution is shown to exist and the formation
of baryon number density inhomogeneities at the end of the drop contraction is
discussed.Comment: 12 pages Phys. Rev. format, uuencoded postscript file including 12
figure
A DMRG Study of Low-Energy Excitations and Low-Temperature Properties of Alternating Spin Systems
We use the density matrix renormalization group (DMRG) method to study the
ground and low-lying excited states of three kinds of uniform and dimerized
alternating spin chains. The DMRG procedure is also employed to obtain
low-temperature thermodynamic properties of these systems. We consider a 2N
site system with spins and alternating from site to site and
interacting via a Heisenberg antiferromagnetic exchange. The three systems
studied correspond to being equal to and
; all of them have very similar properties. The ground state is found
to be ferrimagnetic with total spin . We find that there is
a gapless excitation to a state with spin , and a gapped excitation to
a state with spin . Surprisingly, the correlation length in the ground
state is found to be very small for this gapless system. The DMRG analysis
shows that the chain is susceptible to a conditional spin-Peierls instability.
Furthermore, our studies of the magnetization, magnetic susceptibility
and specific heat show strong magnetic-field dependences. The product
shows a minimum as a function of temperature T at low magnetic fields; the
minimum vanishes at high magnetic fields. This low-field behavior is in
agreement with earlier experimental observations. The specific heat shows a
maximum as a function of temperature, and the height of the maximum increases
sharply at high magnetic fields. Although all the three systems show
qualitatively similar behavior, there are some notable quantitative differences
between the systems in which the site spin difference, , is large
and small respectively.Comment: 16 LaTeX pages, 13 postscript figure
Edge-Based Compartmental Modeling for Infectious Disease Spread Part III: Disease and Population Structure
We consider the edge-based compartmental models for infectious disease spread
introduced in Part I. These models allow us to consider standard SIR diseases
spreading in random populations. In this paper we show how to handle deviations
of the disease or population from the simplistic assumptions of Part I. We
allow the population to have structure due to effects such as demographic
detail or multiple types of risk behavior the disease to have more complicated
natural history. We introduce these modifications in the static network
context, though it is straightforward to incorporate them into dynamic
networks. We also consider serosorting, which requires using the dynamic
network models. The basic methods we use to derive these generalizations are
widely applicable, and so it is straightforward to introduce many other
generalizations not considered here
Statistical bounds on the dynamical production of entanglement
We present a random-matrix analysis of the entangling power of a unitary
operator as a function of the number of times it is iterated. We consider
unitaries belonging to the circular ensembles of random matrices (CUE or COE)
applied to random (real or complex) non-entangled states. We verify numerically
that the average entangling power is a monotonic decreasing function of time.
The same behavior is observed for the "operator entanglement" --an alternative
measure of the entangling strength of a unitary. On the analytical side we
calculate the CUE operator entanglement and asymptotic values for the
entangling power. We also provide a theoretical explanation of the time
dependence in the CUE cases.Comment: preprint format, 14 pages, 2 figure
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