6,623 research outputs found
Violation of Bell's Inequalities with a Local Theory of Photons
We use a local theory of photons purely as particles to model the
single-photon experiment proposed by Tan, Walls, and Collett. Like Tan et al.
we are able to derive a violation of Bell's inequalities for photon counts
coincidence measurements. Our local probabilistic theory does not use any
specific quantum mechanical calculations.Comment: LaTeX, 11 pages, one figure (in LaTeX), submitted to Foundations of
Physics Letter
Entropy, diffusivity and the energy landscape of a water-like fluid
Molecular dynamics simulations and instantaneous normal mode (INM) analysis
of a fluid with core-softened pair interactions and water-like liquid-state
anomalies are performed to obtain an understanding of the relationship between
thermodynamics, transport properties and the poten- tial energy landscape.
Rosenfeld-scaling of diffusivities with the thermodynamic excess and pair
correlation entropy is demonstrated for this model. The INM spectra are shown
to carry infor- mation about the dynamical consequences of the interplay
between length scales characteristic of anomalous fluids, such as bimodality of
the real and imaginary branches of the frequency distribu- tion. The INM
spectral information is used to partition the liquid entropy into two
contributions associated with the real and imaginary frequency modes; only the
entropy contribution from the imaginary branch captures the non-monotonic
behaviour of the excess entropy and diffusivity in the anomalous regime of the
fluid
Association of socioeconomic status with inflammatory markers: a two cohort comparison.
OBJECTIVE: To assess the association between socioeconomic status (SES) and inflammatory markers using two different European population samples.
METHODS: We used data from the CoLaus (N=6412, Lausanne, Switzerland) and EPIPorto (N=1205, Porto, Portugal) studies. Education and occupational position were used as indicators of socioeconomic status (SES). High-sensitivity C-reactive protein (hs-CRP) was available for both cohorts. Interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) were available in CoLaus; leukocyte count and fibrinogen in EPIPorto.
RESULTS: We showed that low SES was significantly associated with high inflammation in both studies. We also showed that behavioural factors contributed the most to SES differences in inflammation. In both studies the larger difference between the lowest and the highest SES was observed for hs-CRP. In the Swiss sample, a linear association between education and hs-CRP persisted after adjustment for all mediating factors and confounders considered (p for linear trend <0.001).
CONCLUSION: Large social differences exist in inflammatory activity, in part independently from demographic and behavioural factors, chronic conditions and medication use. SES differences in inflammation are also similar in countries with different underlying socioeconomic conditions
Composição bromatológica e digestibilidade aparente da parte aérea seca da mandioca na alimentação de tilápia-do-nilo.
O objetivo deste trabalho foi avaliar o efeito da secagem da parte aérea da mandioca, ao sol e à sombra, sobre a composição bromatológica e o coeficiente de digestibilidade aparente (CDA) de nutrientes, energia e aminoácidos para tilápia-do-nilo (Oreochromis niloticus). Não houve diferença entre os métodos de secagem para a composição bromatológica. O CDA da proteína bruta apresentou maior digestibilidade para a parte aérea seca à sombra. A secagem da parte aérea da mandioca à sombra permite maior conservação do conteúdo proteico e melhor digestibilidade aparente da fração proteica e aminoacídica para a tilápia-do-nilo
Desempenho de cultivares de sorgo sacarino para produção de etanol em diferentes épocas de semeadura, no município de Pelotas, RS.
Determinação da melhor população de plantas no espaçamento 0,5 m para cultivares de sorgo sacarino adaptadas ao Rio Grande do Sul.
Understanding stellar activity-induced radial velocity jitter using simultaneous K2 photometry and HARPS RV measurements
One of the best ways to improve our understanding of the stellar
activity-induced signal in radial velocity (RV) measurements is through
simultaneous high-precision photometric and RV observations. This is of prime
importance to mitigate the RV signal induced by stellar activity and therefore
unveil the presence of low-mass exoplanets. The K2 Campaign 7 and 8
field-of-views were located in the southern hemisphere, and provided a unique
opportunity to gather unprecedented simultaneous high precision photometric
observation with K2 and high-precision RV measurements with the HARPS
spectrograph to study the relationship between photometric variability and RV
jitter. We observed nine stars with different levels of activity; from quiet to
very active. We probe the presence of any meaningful relation between measured
RV jitter and the simultaneous photometric variation, and also other activity
indicators (e.g. BIS, FWHM, , and F8), by evaluating the strength
and significance of the correlation between RVs and each indicator. We found
that for the case of very active stars, strong and significant correlations
exist between almost all the observables and measured RVs; however, for lower
activity levels the correlations become random. Except for the F8 which its
strong correlation with RV jitter persists over a wide range of stellar
activity level, and thus our result suggests that F8 might be a powerful proxy
for activity induced RV jitter. Moreover, we examine the capability of two
state-of-the-art modeling techniques, namely the FF' method and SOAP2.0, in
accurately predicting the RV jitter amplitude using the simultaneous
photometric observation. We found that for the very active stars both
techniques can reasonably well predict the amplitude of the RV jitter, however,
at lower activity levels the FF' method underpredicts the RV jitter amplitude.Comment: 13 pages, 7 figures, 2 tables, accepted for publication in A&
Determinação da melhor população de plantas no espaçamento 0,7 m para cultivares de sorgo sacarino adaptadas ao Rio Grande do Sul.
Optical Line Emission from z6.8 Sources with Deep Constraints on Ly Visibility
We analyze a sample of -dropout galaxies in the CANDELS GOODS South and
UDS fields that have been targeted by a dedicated spectroscopic campaign aimed
at detecting their Ly line. Deep IRAC observations at 3.6 and 4.5
m are used to determine the strength of optical emission lines affecting
these bands at z6.5-6.9 in order to i) investigate possible physical
differences between Ly emitting and non-emitting sources; ii) constrain
the escape fraction of ionizing photons; iii) provide an estimate of the
specific star-formation rate at high redshifts. We find evidence of strong
[OIII]+H emission in the average (stacked) SEDs of galaxies both with
and without Ly emission. The blue IRAC [3.6]-[4.5] color of the stack
with detected Ly line can be converted into a rest-frame equivalent
width EW([OIII]+H)=1500 assuming a flat intrinsic
stellar continuum. This strong optical line emission enables a first estimate
of f20% on the escape fraction of ionizing photons from
Ly detected objects. The objects with no Ly line show less
extreme EW([OIII]+H)=520 suggesting different
physical conditions of the HII regions with respect to Ly-emitting
ones, or a larger f. The latter case is consistent with a combined
evolution of f and the neutral hydrogen fraction as an explanation of
the lack of bright Ly emission at z6. A lower limit on the specific
star formation rate, SSFR9.1 for galaxies at these redshifts can be derived from the
spectroscopically confirmed sample.Comment: 10 pages, 7 figures; The Astrophysical Journal in press; matched to
the published versio
Inequalities for dealing with detector inefficiencies in Greenberger-Horne-Zeilinger-type experiments
In this article we show that the three-particle GHZ theorem can be
reformulated in terms of inequalities, allowing imperfect correlations due to
detector inefficiencies. We show quantitatively that taking into accout those
inefficiencies, the published results of the Innsbruck experiment support the
nonexistence of local hidden variables that explain the experimental result.Comment: LaTeX2e, 9 pages, 3 figures, to appear in Phys. Rev. Let
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