13,411 research outputs found
Phase Transitions in Multicomponent String Model
We propose a one-dimensional model of a string decorated with adhesion
molecules (stickers) to mimic multicomponent membranes in restricted
geometries. The string is bounded by two parallel walls and it interacts with
one of them by short range attractive forces while the stickers are attracted
by the other wall. The exact solution of the model in the case of infinite wall
separation predicts both continuous and discontinuous transitions between
phases characterised by low and high concentration of stickers on the string.
Our model exhibits also coexistence of these two phases, similarly to models of
multicomponent membranes.Comment: letter, 8 pages, 3 figure
Seasonal activity patterns of the frog, Crinia signifera (Anura: Myobatrachidae), in southern Tasmania, Australia
We investigated the seasonal adaptations of the myobatrachid frog Girard, 1863 in a commercial forest in southern Tasmania, Australia. Seasonal variation in activity patterns, body size and body condition was investigated. Although C does not hibernate over winter, activity levels arc much reduced during this time. Females trapped in summer were smaller than those captured throughout the remainder of the year. We interpreted seasonal variation in the condition of captured frogs as an indication that breeding in spring and
early summer is metabolically costly and fat stores are replenished by extensive foraging in summer. Fat stores accumulated in summer and autumn by males are used for body maintenance over winter and breeding in the following spring
Working With Faith-Based Communities to Develop an Education Tool kit on Relationships, Sexuality, and Contraception
Communities disproportionately affected from higher rates of unplanned teen births are in need of sustainable approaches to prevention strategies. One approach is to build the capacity of faith-based communities (FBCs) to address the sexual health needs of the surrounding community. However there is a need for comprehensive, user-friendly resources designed for FBCs that provide critical decision-making information related to pregnancy prevention inclusive of contraception. Using community-based, theoretical and practice-informed strategies, we developed a user-friendly sexuality education tool kit in five phases: (1) building relationships with faith leaders; (2) piloting educational sessions within churches; (3) gaining insight from participating faith leaders; (4) creating the tool kit; and (5) collecting feedback from training and implementation. Our findings suggest faith leaders remained motivated to overcome perceived barriers by their mission to serve their communities. A sexuality education tool kit that is respectful and guided by the input of FBCs can be a viable and innovative approach to address teen pregnancy
Molecular electric dipole moments: from light to heavy molecules using a relativistic VQE algorithm
The quantum-classical hybrid Variational Quantum Eigensolver (VQE) algorithm
is recognized to be the most suitable approach to obtain ground state energies
of quantum many-body systems in the noisy intermediate scale quantum era. In
this work, we extend the VQE algorithm to the relativistic regime and carry out
quantum simulations to obtain ground state energies as well as molecular
permanent electric dipole moments of single-valence diatomic molecules,
beginning with the light BeH molecule and all the way to the heavy radioactive
RaH molecule. We study the correlation trends in these systems as well as
assess the precision in our results within our active space of 12 qubits
The First Data Release of the KODIAQ Survey
We present and make publicly available the first data release (DR1) of the
Keck Observatory Database of Ionized Absorption toward Quasars (KODIAQ) survey.
The KODIAQ survey is aimed at studying galactic and circumgalactic gas in
absorption at high-redshift, with a focus on highly-ionized gas traced by OVI,
using the HIRES spectrograph on the Keck-I telescope. KODIAQ DR1 consists of a
fully-reduced sample of 170 quasars at 0.29 < z_em < 5.29 observed with HIRES
at high resolution (36,000 <= R <= 103,000) between 2004 and 2012. DR1 contains
247 spectra available in continuum normalized form, representing a sum total
exposure time of ~1.6 megaseconds. These co-added spectra arise from a total of
567 individual exposures of quasars taken from the Keck Observatory Archive
(KOA) in raw form and uniformly processed using a HIRES data reduction package
made available through the XIDL distribution. DR1 is publicly available to the
community, housed as a higher level science product at the KOA. We will provide
future data releases that make further QSOs, including those with pre-2004
observations taken with the previous-generation HIRES detectors.Comment: 14 pages, 9 figures, Submitted to AJ. All data products available at
the Keck Observatory Archive beginning May 15, 2015. URL:
https://koa.ipac.caltech.edu/applications/KODIA
Spatial and Temporal Patterns of Mercury Accumulation in Lacustrine Sediments across the Laurentian Great Lakes Region
Data from 104 sediment cores from the Great Lakes and “inland lakes” in the region were compiled to assess historical and recent changes in mercury (Hg) deposition. The lower Great Lakes showed sharp increases in Hg loading c. 1850-1950 from point-source water dischargers, with marked decreases during the past half century associated with effluent controls and decreases in the industrial use of Hg. In contrast, Lake Superior and inland lakes exhibited a pattern of Hg loading consistent with an atmospheric source - gradual increases followed by recent (post-1980) decreases. Variation in sedimentary Hg flux among inland lakes was primarily attributed to the ratio of watershed area: lake area, and secondarily to a lake’s proximity to emission sources. A consistent region-wide decrease (~20%) of sediment Hg flux suggests that controls on local and regional atmospheric Hg emissions have been effective in decreasing the supply of Hg to Lake Superior and inland lakes
Enhancing Acceleration Radiation from Ground-State Atoms via Cavity Quantum Electrodynamics
When ground state atoms are accelerated through a high Q microwave cavity,
radiation is produced with an intensity which can exceed the intensity of Unruh
acceleration radiation in free space by many orders of magnitude. The cavity
field at steady state is described by a thermal density matrix under most
conditions. However, under some conditions gain is possible, and when the atoms
are injected in a regular fashion, the radiation can be produced in a squeezed
state
Time evolution of the Rabi Hamiltonian from the unexcited vacuum
The Rabi Hamiltonian describes a single mode of electromagnetic radiation
interacting with a two-level atom. Using the coupled cluster method, we
investigate the time evolution of this system from an initially empty field
mode and an unexcited atom. We give results for the atomic inversion and field
occupation, and find that the virtual processes cause the field to be squeezed.
No anti-bunching occurs.Comment: 25 pages, 8 figures, RevTe
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