726 research outputs found
Curtailing the Dark Side in Non-Standard Neutrino Interactions
In presence of non-standard neutrino interactions the neutrino flavor
evolution equation is affected by a degeneracy which leads to the so-called
LMA-Dark solution. It requires a solar mixing angle in the second octant and
implies an ambiguity in the neutrino mass ordering. Non-oscillation experiments
are required to break this degeneracy. We perform a combined analysis of data
from oscillation experiments with the neutrino scattering experiments CHARM and
NuTeV. We find that the degeneracy can be lifted if the non-standard neutrino
interactions take place with down quarks, but it remains for up quarks.
However, CHARM and NuTeV constraints apply only if the new interactions take
place through mediators not much lighter than the electroweak scale. For light
mediators we consider the possibility to resolve the degeneracy by using data
from future coherent neutrino-nucleus scattering experiments. We find that, for
an experiment using a stopped-pion neutrino source, the LMA-Dark degeneracy
will either be resolved, or the presence of new interactions in the neutrino
sector will be established with high significance.Comment: 33 pages, 9 figures. Minor modifications. Version accepted for
publication in JHE
Strategies to Ascertain the Sign of the Spatial Curvature
The second law of thermodynamics, in the presence of gravity, is known to hold at small scales, as in the case of black holes and self-gravitating radiation spheres. Using the Friedmann-Lemaître-Robertson-Walker metric and the history of the Hubble factor, we argue that this law also holds at cosmological scales. Based on this, we study the connection between the deceleration parameter and the spatial curvature of the metric, Wk, and set limits on the latter, vàlid for any homogeneous and isotropic cosmological model. Likewise, we devise strategies to determine the sign of the spatial curvature index k. Finally, assuming the lambda cold dark matter model is correct, we find that the acceleration of the cosmic expansion is increasing today
Determination of C-reactive protein in female dogs with benign and malignant mammary tumors
Indexación: ScieloSUMMARY
The aim of this study was to determine C-reactive protein levels in dogs with benign and malignant mammary tumors. Thirty female dogs, with ages ranging between 6 and 15 years and with no distinction of breed were used for this purpose. The animals were divided into 3 different groups of 10 dogs each: Group 1 (control), Group 2 (benign mammary tumor) and Group 3 (malignant mammary tumor). The neoplasias were classified histologically and C-reactive protein (CRP) levels were analyzed using a human turbidimetric immunoassay validated for dogs. Group 3 had the highest values (mean: 8.2 mg/L; median: 7.1 mg/L) of C-reactive protein compared with the other groups (P < 0.05). According to a discriminant analysis, a female dog with a mammary tumor and CRP values ≥ 8 mg/L has a 61% or greater probability of this tumor being malignant.
Key words: C-reactive protein, mammary tumors, malignant.
RESUMEN
El objetivo de este estudio fue determinar los niveles séricos de proteína C-reactiva en caninos con neoplasias mamarias benignas y malignas. Se determinaron concentraciones séricas de proteína C-reactiva en 30 hembras caninas con edades entre 6 y 15 años, sin discriminación de raza y no esterilizadas. Los animales fueron divididos en tres grupos de 10 individuos cada uno: grupo 1 (control), grupo 2 (neoplasia mamaria benigna) y grupo 3 (neoplasia mamaria maligna). Las neoplasias mamarias fueron clasificadas mediante estudio histopatológico en benignas o malignas. Los niveles séricos de proteína C-reactiva se determinaron a partir de un ensayo inmunoturbidimétrico de uso humano validado en caninos. El grupo 3 fue el que presentó los valores más altos (media 8,2 mg/L, mediana 7,1 mg/L) de proteína C-reactiva con respecto a los otros dos grupos (P < 0,05). De acuerdo con un análisis discriminante, una perra con neoplasia mamaria y valores de CRP ≥ 8 mg/L tiene una probabilidad de un 61% o más de que ésta sea maligna.
Palabras clave: proteína C-reactiva, neoplasia mamaria, maligna
Determining the nuclear neutron distribution from Coherent Elastic neutrino-Nucleus Scattering: current results and future prospects
Coherent elastic neutrino-nucleus scattering (CENS), a process recently
measured for the first time at ORNL's Spallation Neutron Source, is directly
sensitive to the weak form factor of the nucleus. The European Spallation
Source (ESS), presently under construction, will generate the most intense
pulsed neutrino flux suitable for the detection of CENS. In this paper we
quantify its potential to determine the root mean square radius of the
point-neutron distribution, for a variety of target nuclei and a suite of
detectors. To put our results in context we also derive, for the first time, a
constraint on this parameter from the analysis of the energy and timing data of
the CsI detector at the COHERENT experiment.Comment: 16 pages, 4 figures. Minor text changes and references added. Matches
version accepted by JHE
Improved global fit to Non-Standard neutrino Interactions using COHERENT energy and timing data
We perform a global fit to neutrino oscillation and coherent neutrino-nucleus
scattering data, using both timing and energy information from the COHERENT
experiment. The results are used to set model-independent bounds on
four-fermion effective operators inducing non-standard neutral-current neutrino
interactions. We quantify the allowed ranges for their Wilson coefficients, as
well as the status of the LMA-D solution, for a wide class of new physics
models with arbitrary ratios between the strength of the operators involving up
and down quarks. Our results are presented for the COHERENT experiment alone,
as well as in combination with the global data from oscillation experiments. We
also quantify the dependence of our results for COHERENT with respect to the
choice of quenching factor, nuclear form factor, and the treatment of the
backgrounds.Comment: 25 pages, 9 figures, 2 tables. Added an appendix with updated results
accounting for the data available in July 202
Determining the nuclear neutron distribution from Coherent Elastic neutrino-Nucleus Scattering: current results and future prospects
Coherent Elastic neutrino-Nucleus Scattering (CEνNS), a process recently measured for the first time at ORNL's Spallation Neutron Source, is directly sensitive to the weak form factor of the nucleus. The European Spallation Source (ESS), presently under construction, will generate the most intense pulsed neutrino flux suitable for the detection of CEνNS. In this paper we quantify its potential to determine the root mean square radius of the point-neutron distribution, for a variety of target nuclei and a suite of detectors. To put our results in context we also derive, for the first time, a constraint on this parameter from the analysis of the energy and timing data of the CsI detector at the COHERENT experiment
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