851 research outputs found
Predicting Community COVID-19 Public Health Needs Through Wastewater Based Epidemiology, Maine USA
This research examines the applicability of various wastewater based epidemiological (WBE) approaches to predicting Coronavirus disease 2019 (COVID-19) incidence in four different Maine communities.
The study analyzes the predictive fit of COVID-19 cases based on a simple predictive model, a linear regression model, and a Susceptible, Exposed, Infected, and Recovered (SEIR) differential equation model.
The findings further bolster existing evidence supporting that WBE can play a vital supplementary role in COVID-19 disease surveillance and prediction. predictive models through WBE is becoming an important public health surveillance tool and leveraging it in the future could provide numerous benefits to community level understanding and response related to population health.https://dune.une.edu/ph_ile/1001/thumbnail.jp
All-Optical Production of Chromium Bose-Einstein Condensates
We report on the production of ^52Cr Bose Einstein Condensates (BEC) with an
all-optical method. We first load 5.10^6 metastable chromium atoms in a 1D
far-off-resonance optical trap (FORT) from a Magneto Optical Trap (MOT), by
combining the use of Radio Frequency (RF) frequency sweeps and depumping
towards the ^5S_2 state. The atoms are then pumped to the absolute ground
state, and transferred into a crossed FORT in which they are evaporated. The
fast loading of the 1D FORT (35 ms 1/e time), and the use of relatively fast
evaporative ramps allow us to obtain in 20 s about 15000 atoms in an almost
pure condensate.Comment: 4 pages, 4 figure
Testes de envelhecimento precoce para sementes de bracatinga (Mimosa scabrella Benth).
O trabalho objetiva determinar as melhores temperaturas e tempos de exposição dentro da camara para a realização do teste de envelhecimento precoce de sementes de Bracatinga (Mimosa scabrella Benth).bitstream/item/96269/1/CPAF-AP-2000-Teste-Bracatinga.pd
Critical regime of two dimensional Ando model: relation between critical conductance and fractal dimension of electronic eigenstates
The critical two-terminal conductance and the spatial fluctuations of
critical eigenstates are investigated for a disordered two dimensional model of
non-interacting electrons subject to spin-orbit scattering (Ando model). For
square samples, we verify numerically the relation between critical conductivity and
the fractal information dimension of the electron wave function, . Through a detailed numerical scaling analysis of the two-terminal
conductance we also estimate the critical exponent that
governs the quantum phase transition.Comment: IOP Latex, 7 figure
A Very Low Resource Language Speech Corpus for Computational Language Documentation Experiments
Most speech and language technologies are trained with massive amounts of
speech and text information. However, most of the world languages do not have
such resources or stable orthography. Systems constructed under these almost
zero resource conditions are not only promising for speech technology but also
for computational language documentation. The goal of computational language
documentation is to help field linguists to (semi-)automatically analyze and
annotate audio recordings of endangered and unwritten languages. Example tasks
are automatic phoneme discovery or lexicon discovery from the speech signal.
This paper presents a speech corpus collected during a realistic language
documentation process. It is made up of 5k speech utterances in Mboshi (Bantu
C25) aligned to French text translations. Speech transcriptions are also made
available: they correspond to a non-standard graphemic form close to the
language phonology. We present how the data was collected, cleaned and
processed and we illustrate its use through a zero-resource task: spoken term
discovery. The dataset is made available to the community for reproducible
computational language documentation experiments and their evaluation.Comment: accepted to LREC 201
Germinação de sementes de forrageiras perenes em baixas temperaturas e diferentes profundidades.
Higher Order Conformal Invariance of String Backgrounds Obtained by O(d,d) Transformations
Proposals that boosts of trivial backgrounds lead to non-trivial
conformally invariant backgrounds are checked to two loop order. We find that
conformal invariance can be achieved by adding simple higher order corrections
to the metric and dilaton.Comment: 8 page
w_{\infty} Algebras, Conformal Mechanics, and Black Holes
We discuss BPS solitons in gauged , D=4 supergravity. The
solitons represent extremal black holes interpolating between different vacua
of anti-de Sitter spaces. The isometry superalgebras are determined and the
motion of a superparticle in the extremal black hole background is studied and
confronted with superconformal mechanics. We show that the Virasoro symmetry of
conformal mechanics, which describes the dynamics of the superparticle near the
horizon of the extremal black hole under consideration, extends to a symmetry
under the algebra of area-preserving diffeomorphisms. We find that
a Virasoro subalgebra of can be associated to the Virasoro algebra
of the asymptotic symmetries of . In this way spacetime diffeomorphisms
of translate into diffeomorphisms in phase space: our system offers an
explicit realization of the correspondence. Using the
dimensionally reduced action, the central charge is computed. Finally, we also
present generalizations of superconformal mechanics which are invariant under
and superextensions of .Comment: Latex, 23 pages, minor errors corrected, references added; final
version to appear in Class. Quant. Gra
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