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ranacapa: An R package and Shiny web app to explore environmental DNA data with exploratory statistics and interactive visualizations.
Environmental DNA (eDNA) metabarcoding is becoming a core tool in ecology and conservation biology, and is being used in a growing number of education, biodiversity monitoring, and public outreach programs in which professional research scientists engage community partners in primary research. Results from eDNA analyses can engage and educate natural resource managers, students, community scientists, and naturalists, but without significant training in bioinformatics, it can be difficult for this diverse audience to interact with eDNA results. Here we present the R package ranacapa, at the core of which is a Shiny web app that helps perform exploratory biodiversity analyses and visualizations of eDNA results. The app requires a taxonomy-by-sample matrix and a simple metadata file with descriptive information about each sample. The app enables users to explore the data with interactive figures and presents results from simple community ecology analyses. We demonstrate the value of ranacapa to two groups of community partners engaging with eDNA metabarcoding results
Organ Donation and Utilization in the United States, 1997–2006
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75743/1/j.1600-6143.2008.02171.x.pd
Using the etalon effect for in-situ balancing of the Advanced Virgo arm cavities
Several large-scale interferometric gravitational-wave detectors use resonant
arm cavities to enhance the light power in the interferometer arms. These
cavities are based on different optical designs: One design uses wedged input
mirrors to create additional optical pick-off ports for deriving control
signals. The second design employs input mirrors without wedge and thus offers
the possibility to use the etalon effect inside the input mirrors for tuning
the finesse of the arm cavities. In this article we introduce a concept of
maximized flexibility that combines both of these options, by featuring wedges
at the input mirrors and using the etalon effect instead in the end mirrors. We
present a design for the arm cavities of Advanced Virgo. We have used numerical
simulations to derive requirements for the manufacturing accuracy of an end
mirror etalon for Advanced Virgo. Furthermore, we give analytical
approximations for the achievable tuning range of the etalon in dependence on
the reflectance, the curvature and the orientation of the etalon back surface.Comment: 12 pages, 6 Figure
Non-mean-field theory of anomalously large double-layer capacitance
Mean-field theories claim that the capacitance of the double-layer formed at
a metal/ionic conductor interface cannot be larger than that of the Helmholtz
capacitor, whose width is equal to the radius of an ion. However, in some
experiments the apparent width of the double-layer capacitor is substantially
smaller. We propose an alternate, non-mean-field theory of the ionic
double-layer to explain such large capacitance values. Our theory allows for
the binding of discrete ions to their image charges in the metal, which results
in the formation of interface dipoles. We focus primarily on the case where
only small cations are mobile and other ions form an oppositely-charged
background. In this case, at small temperature and zero applied voltage dipoles
form a correlated liquid on both contacts. We show that at small voltages the
capacitance of the double-layer is determined by the transfer of dipoles from
one electrode to the other and is therefore limited only by the weak
dipole-dipole repulsion between bound ions, so that the capacitance is very
large. At large voltages the depletion of bound ions from one of the capacitor
electrodes triggers a collapse of the capacitance to the much smaller
mean-field value, as seen in experimental data. We test our analytical
predictions with a Monte Carlo simulation and find good agreement. We further
argue that our ``one-component plasma" model should work well for strongly
asymmetric ion liquids. We believe that this work also suggests an improved
theory of pseudo-capacitance.Comment: 19 pages, 14 figures; some Monte Carlo results and a section about
aqueous solutions adde
Probing seed black holes using future gravitational-wave detectors
Identifying the properties of the first generation of seeds of massive black
holes is key to understanding the merger history and growth of galaxies.
Mergers between ~100 solar mass seed black holes generate gravitational waves
in the 0.1-10Hz band that lies between the sensitivity bands of existing
ground-based detectors and the planned space-based gravitational wave detector,
the Laser Interferometer Space Antenna (LISA). However, there are proposals for
more advanced detectors that will bridge this gap, including the third
generation ground-based Einstein Telescope and the space-based detector DECIGO.
In this paper we demonstrate that such future detectors should be able to
detect gravitational waves produced by the coalescence of the first generation
of light seed black-hole binaries and provide information on the evolution of
structure in that era. These observations will be complementary to those that
LISA will make of subsequent mergers between more massive black holes. We
compute the sensitivity of various future detectors to seed black-hole mergers,
and use this to explore the number and properties of the events that each
detector might see in three years of observation. For this calculation, we make
use of galaxy merger trees and two different seed black hole mass distributions
in order to construct the astrophysical population of events. We also consider
the accuracy with which networks of future ground-based detectors will be able
to measure the parameters of seed black hole mergers, in particular the
luminosity distance to the source. We show that distance precisions of ~30% are
achievable, which should be sufficient for us to say with confidence that the
sources are at high redshift.Comment: 14 pages, 6 figures, 2 tables, accepted for proceedings of 13th GWDAW
meetin
Control sideband generation for dual-recycled laser interferometric gravitational wave detectors
We present a discussion of the problems associated with generation of multiple control sidebands for length sensing and control of dual-recycled, cavity-enhanced Michelson interferometers and the motivation behind more complicated sideband generation methods. We focus on the Mach–Zehnder interferometer as a topological solution to the problem and present results from tests carried out at the Caltech 40 m prototype gravitational wave detector. The consequences for sensing and control for advanced interferometry are discussed, as are the implications for future interferometers such as Advanced LIGO
Wnt signaling contributes to vascular calcification by induction of matrix metalloproteinases
Revisit relic gravitational waves based on the latest CMB observations
According to the CMB observations, Mielczarek (\cite{Mielczarek}) evaluated
the reheating temperature, which could help to determine the history of the
Universe. In this paper, we recalculate the reheating temperature using the new
data from WMAP 7 observations. Based on that, we list the approximate solutions
of relic gravitational waves (RGWs) for various frequency bands. With the
combination of the quantum normalization of RGWs when they are produced and the
CMB observations, we obtain the relation between the tensor-to-scalar ratio
and the inflation index for a given scalar spectral index . As a
comparison, the diagram in the slow-roll inflation model is also
given. Thus, the observational limits of from CMB lead to the constraints
on the value of . Then, we illustrate the energy density spectrum of
RGWs with the quantum normalization for different values of and the
corresponding . For comparison, the energy density spectra of RGWs with
parameters based on slow-roll inflation are also discussed. We find that the
values of affect the spectra of RGWs sensitively in the very high
frequencies. Based on the current and planed gravitational wave detectors, we
discuss the detectabilities of RGWs.Comment: 16 pages, 6 figures, accepted for publication in Class. Quantum Gra
Recipient Morbidity After Living and Deceased Donor Liver Transplantation: Findings from the A2ALL Retrospective Cohort Study â€
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72284/1/j.1600-6143.2008.02440.x.pd
Cosmography with the Einstein Telescope
Einstein Telescope (ET) is a 3rd generation gravitational-wave (GW) detector
that is currently undergoing a design study. ET can detect millions of compact
binary mergers up to redshifts 2-8. A small fraction of mergers might be
observed in coincidence as gamma-ray bursts, helping to measure both the
luminosity distance and red-shift to the source. By fitting these measured
values to a cosmological model, it should be possible to accurately infer the
dark energy equation-of-state, dark matter and dark energy density parameters.
ET could, therefore, herald a new era in cosmology.Comment: 4 pages, 2 figure
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