45 research outputs found
Identification and reconstruction of low-energy electrons in the ProtoDUNE-SP detector
Measurements of electrons from interactions are crucial for the Deep
Underground Neutrino Experiment (DUNE) neutrino oscillation program, as well as
searches for physics beyond the standard model, supernova neutrino detection,
and solar neutrino measurements. This article describes the selection and
reconstruction of low-energy (Michel) electrons in the ProtoDUNE-SP detector.
ProtoDUNE-SP is one of the prototypes for the DUNE far detector, built and
operated at CERN as a charged particle test beam experiment. A sample of
low-energy electrons produced by the decay of cosmic muons is selected with a
purity of 95%. This sample is used to calibrate the low-energy electron energy
scale with two techniques. An electron energy calibration based on a cosmic ray
muon sample uses calibration constants derived from measured and simulated
cosmic ray muon events. Another calibration technique makes use of the
theoretically well-understood Michel electron energy spectrum to convert
reconstructed charge to electron energy. In addition, the effects of detector
response to low-energy electron energy scale and its resolution including
readout electronics threshold effects are quantified. Finally, the relation
between the theoretical and reconstructed low-energy electron energy spectrum
is derived and the energy resolution is characterized. The low-energy electron
selection presented here accounts for about 75% of the total electron deposited
energy. After the addition of lost energy using a Monte Carlo simulation, the
energy resolution improves from about 40% to 25% at 50~MeV. These results are
used to validate the expected capabilities of the DUNE far detector to
reconstruct low-energy electrons.Comment: 19 pages, 10 figure
Impact of cross-section uncertainties on supernova neutrino spectral parameter fitting in the Deep Underground Neutrino Experiment
A primary goal of the upcoming Deep Underground Neutrino Experiment (DUNE) is
to measure the MeV neutrinos produced by a Galactic
core-collapse supernova if one should occur during the lifetime of the
experiment. The liquid-argon-based detectors planned for DUNE are expected to
be uniquely sensitive to the component of the supernova flux, enabling
a wide variety of physics and astrophysics measurements. A key requirement for
a correct interpretation of these measurements is a good understanding of the
energy-dependent total cross section for charged-current
absorption on argon. In the context of a simulated extraction of
supernova spectral parameters from a toy analysis, we investigate the
impact of modeling uncertainties on DUNE's supernova neutrino
physics sensitivity for the first time. We find that the currently large
theoretical uncertainties on must be substantially reduced
before the flux parameters can be extracted reliably: in the absence of
external constraints, a measurement of the integrated neutrino luminosity with
less than 10\% bias with DUNE requires to be known to about 5%.
The neutrino spectral shape parameters can be known to better than 10% for a
20% uncertainty on the cross-section scale, although they will be sensitive to
uncertainties on the shape of . A direct measurement of
low-energy -argon scattering would be invaluable for improving the
theoretical precision to the needed level.Comment: 25 pages, 21 figure
A narrative review of health research capacity strengthening in low and middle-income countries: lessons for conflict-affected areas
Abstract Conducting health research in conflict-affected areas and other complex environments is difficult, yet vital. However, the capacity to undertake such research is often limited and with little translation into practice, particularly in poorer countries. There is therefore a need to strengthen health research capacity in conflict-affected countries and regions. In this narrative review, we draw together evidence from low and middle-income countries to highlight challenges to research capacity strengthening in conflict, as well as examples of good practice. We find that authorship trends in health research indicate global imbalances in research capacity, with implications for the type and priorities of research produced, equity within epistemic communities and the development of sustainable research capacity in low and middle-income countries. Yet, there is little evidence on what constitutes effective health research capacity strengthening in conflict-affected areas. There is more evidence on health research capacity strengthening in general, from which several key enablers emerge: adequate and sustained financing; effective stewardship and equitable research partnerships; mentorship of researchers of all levels; and effective linkages of research to policy and practice. Strengthening health research capacity in conflict-affected areas needs to occur at multiple levels to ensure sustainability and equity. Capacity strengthening interventions need to take into consideration the dynamics of conflict, power dynamics within research collaborations, the potential impact of technology, and the wider political environment in which they take place
DESHIDRATACIÓN DE FRUCTOSA PARA OBTENER HIDROXLMETILFURFURAL
The objective of this work is the transformation of fructose to 4-hydroxymethylfurfural by a dehydratation process using the 4-toluenesulfonic acid as catalyst . The reaction was carried out using solutions of fructose in water and fructose in water-acetone (50% volume) in a batch reactor at temperatures of 372 K and 348 K respectively. The yield reached a maximum of 16% to hydroxymethylfurfural, an intermediate for obtaining fuel furan.El objetivo del presente trabajo es la transformación de la fructosa a 4-hidroximetilfurfural por un proceso de deshidratación utilizando como catalizador el ácido 4-toluensulfónico. La reacción se realizó utilizando soluciones de fructosa en agua y de fructosa en agua-acetona (mezcla 50% en volumen) en un reactor batch y a temperaturas de 372 K y 348 K respectivamente. Los rendimientos alcanzaron un máximo del 16% hacia hidroximetilfurfural, un compuesto intermedio para la obtención del combustible furano
Use of Leuconostoc Mesenteroides to Produce a Dextran Bioflocculant
In this study, we aimed to determine the in vitro activity of Leuconostoc mesenteroides var. mesenteroides isolated from sugar-industry effluents to produce a dextran bioflocculant from sucrose as a low-cost substrate. L. mesenteroides strains present in residual cane juice from a sugar factory were isolated and biochemically identified using Mayeux, Sandine, and Elliker agar (MSE) as a selective medium. The strain number 3 (LM03) was biochemically identified as L. mesenteroides var. mesenteroides, which was used for this study. The concentration of dextran was quantified by dry weight, the morphology and purity were evaluated using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Flocculation was evaluated via turbidimetric assays in different pH ranges from sugar-industry effluents and doses of dextran. To evaluate the flocculant activity according to the effect of pH, a jar test kit from Phipps and Bird, USA, was used with the sample recollected from the effluent (sugar industry). The pH of the samples was adjusted to 7, 8, 9, 10 and 11, with a dose of 40 ppm (dextran dose) at a fast and slow speed of 150 and 50 rpm, respectively. To evaluate the influence of the dose of dextran, values of 5, 20 and 40 ppm were used with fast speeds of 180–150 rpm and slow speeds of 30–50 rpm, respectively. The strain (LM03) was able to produce the highest concentration of dextran (26.87 g/L) in 76 h of incubation. The presence of dextran was identified in the MSE agar after incubation and characterized by FTIR, SEM, and EDS. Besides that, we observed that the best flocculation activity was observed at a pH of 9 and a concentration of 40 ppm of dextran, with a fast agitation speed of 150 rpm for 5 min and a slow agitation speed of 50 rpm for 15 min, achieving 77.7% removal of turbidity from the sugar factory effluent. L. mesenteroides was responsible for the bioflocculation of dextran in different sugar-industry effluents
Generation bioelectricity from wastewater using low-cost microbial fuel cells [Generación bioelectricidad a partir de aguas residuales mediante celdas de combustible microbiano de bajo costo]
Las celdas de combustible microbianas (CCMs) son una
tecnología prometedora para el tratamiento de las aguas residuales
y generación de bioelectricidad al mismo tiempo. Esta investigación
se basó en la fabricación de CCMs de una sola cámara a escala de
laboratorio; utilizando como combustible aguas residuales (ARs) y
electrodos metálicos de cobre y zinc. Logrando generar valores picos
de 0.349 ± 0.21 V y 254.3 ± 3.23 µA de voltaje y corriente
respectivamente. El monitoreo de las CCMs mostro que las ARs
mostraron un pH alcalino y valores de conductividad mayores a 70
mS/cm, pasado los 15 días. La densidad de potencia máxima fue de
1.67 ± 0.33 W/cm2
en 393.08 mA/ cm2 de densidad de corriente y los
espectros de FTIR de las ARs iniciales y finales mostraron alta
disminución de los picos de intensidad de los enlaces de
polisacáridos, alcanos, N-H y O-H. Estos resultados demostraron la
utilidad del diseño de las CCMs de una sola cámara para la
producción de bioelectricidad, dando una solución eco amigable con
el medio ambiente y la sociedad.Microbial fuel cells (CCMs) are a promising
technology for treating wastewater and generating bioelectricity at
the same time. This research was based on the manufacture of CCMs
single chamber on a laboratory scale; using as fuel wastewater (ARs)
and copper and zinc metal electrodes. Being able to generate peak
values of 0.349 ± 0.21 V and 254.3 ± 3.23 µA of voltage and current
respectively. The monitoring of the CCMs showed that the ARs
showed an alkaline pH and conductivity values greater than 70 mS /
cm, after 15 days. The maximum power density was 1.67 ± 0.33 W /
cm2 at 393.08 mA / cm2
of current density and the FTIR spectra of
the initial and final ARs showed the abrupt decrease of the intensity
peaks of the polysaccharides, alkanes, NH and OH. These results
demonstrated the usefulness of the design of single chamber CCMs
for the production of bioelectricity, providing an eco-friendly
solution with the environment and society
SIMULACIÓN DE LA OPERACIÓN DE OBTENCIÓN DEL PISCO EN UNA COLUMNA DE DESTILACIÓN DISCONTINUA EMPACADA DE ACERO INOXIDABLE
It presents a model based on the Rayleigh equation to simulate the production of pisco using a batch distillation column packed stainless steel without reflux from grape quebranta of valley of Cañete. Model results are compared with experimental data. The results show that the proposed model can simulate the production of pisco.Se presenta un modelo basado en la ecuación de Rayleigh para simular la obtención de pisco utilizando una columna de destilación discontinua empacada de acero inoxidable sin reflujo a partir de mosto de uva quebranta del valle de Cañete. Los resultados del modelo se comparan con los datos experimentales obtenidos. Los resultados muestran que el modelo propuesto permite simular la producción de pisco
Antimicrobial Potential of Tara Hydroalcoholic Extract (<i>Caesalpinia spinosa</i>) against <i>Streptococcus</i> Associated with Strep Throat
Antibiotics are often prescribed to treat infections caused by group B Streptococcus; however, inappropriate use of antibiotics can develop resistance. Because of this, the research was carried out with the aim of evaluating the in vitro effect of the hydroalcoholic extract of Caesalpinia spinosa (Molina) Kuntze known as Taya or Tara on the viability of β-hemolytic streptococci; an experimental investigation of increasing stimulation was carried out. The hydroalcoholic extract of C. spinosa pods was worked in concentrations of 250, 500, 750, and 1000 mg/mL, which were placed on filter paper discs to perform the sensitivity test following the Kirby–Bauer method. The greatest inhibition of bacterial viability was observed in the penicillin control group (GPT-01) followed by the TCT-04 group (hydroalcoholic Tara extract 1000 mg/mL). In addition, it was found that these groups are statistically different from the rest (p C. spinosa (Molina) Kuntze affects the viability of β-hemolytic streptococci associated with strep pharyngitis and that this antimicrobial activity is due to the presence of tannins, steroidal flavonoid, and alkaloids. Likewise, the tested concentrations of hydroalcoholic Tara extract were found to have better antibacterial activity than erythromycin (15 µg/mL) against β-hemolytic streptococci. These results are hopeful for the traditional or herbal medicine field. However, future in vivo research is needed to determine its effectiveness in humans