Examinando 7.1 Incentivos para publicaciones indizadas por Fecha de asunto

Publicación

Sistema de control adaptivo para pacientes con Diabetes Mellitus Tipo 1

(Consejo Nacional de Ciencia, Tecnología e Innovación Tecnológica, 2004)

Ríos Ríos, Buenaventura

;

Mesías Rodríguez, Walter

El objeto de estudio del presente Libro es entender y controlar la diabetes mellitus Tipo 1, haciendo uso de la teoría de estado y los algoritmos de control de los filtros Kalman, En algunos países del norte está adquiriendo características realmente epidémicas. Todas las personas mayores de 40 años, con ascendientes diabéticos, con exceso de peso o que beben demasiado licor, tienen tendencia a adquirir la enfermedad. De hecho, la diabetes es causante directa o indirectamente del incremento de la tasa de mortalidad en el país, y de la existencia de un gran número de personas invidentes o inválidas. En el Perú, existen aproximadamente un millón de diabéticos, de los cuales el 50% desconoce que padece la enfermedad y se estima que, unos de cada 20 diabéticos sufren de diabetes mellitus Tipo 1, también conocida como diabetes juvenil o insulino dependiente. Frente a ella, los científicos del mundo están desarrollando diversas tecnologías con el fin de aliviar la enfermedad con resultados diversos, dada su aplicabilidad práctica, son los de mayor uso desde hace algunas décadas. Dado que, teórica y experimentalmente, se conoce la ecuación matemática diferencial que relaciona a las variables insulina y glucosa en el organismo humano, es posible integrar estas funciones de medición, control y actuador, en un solo dispositivo electrónico implantable y programable PIMS (Programmable Implantable Medication System)

26

Publicación

Phenolic profiles of andean mashua (Tropaeolum tuberosum Ruíz & Pavón) tubers: Identification by HPLC-DAD and evaluation of their antioxidant activity

(Elsevier Ltd, 2008)

Chirinos R.

;

Campos D.

;

Costa N.

;

Arbizu C.

;

Pedreschi R.

;

Larondelle Y.

Qualitative high performance liquid chromatography with diode array detection (HPLC-DAD) was performed to characterize nonanthocyanin phenolic compounds in three different coloured mashua genotypes. The ORAC antioxidant activity contribution in the tubers related to the type of phenolic compounds present was also evaluated. Phenolic compounds were analysed by separating them into four main fractions: fraction I obtained by means of a liquid–liquid partition with ethyl acetate and fractions II, III and IV obtained by elution on a Sephadex LH-20 column. Fraction I revealed the presence of gallic acid, gallocatechin, procyanidin B2 and epigallocatechin. Other phenolic compounds such as hydroxycinnamic and hydroxybenzoic acid derivatives, rutin and/or myricetin derivatives were also present in fraction I. Fraction II was mainly composed of epicatechin, hydroxycinnamic and hydroxybenzoic acid derivatives. Fraction III presented mainly anthocyanins for the purple coloured mashua tubers and rutin, hydroxycinnamic acid and hydroxybenzoic acid derivatives for the yellow coloured genotype. Fraction IV was composed of proanthocyanidins. Alkaline and acid hydrolysis of the different fractions revealed the presence of gallocatechin, epicatechin, p-coumaric acid, o-coumaric acid, cinnamic acid, protocatechuic acid, rutin and quercetin as the main phenolic moieties present. The proanthocyanidin fractions were the major contributors to the ORAC antioxidant activity of the mashua tubers for two of the three genotypes (34.7–39.2%). The results obtained in the present study confirm that mashua tubers constitute a promising source of antioxidant phenolics and could potentially be considered as a functional food with beneficial health effects.

13

Publicación

Preliminary results from the MINERvA experiment

(Sissa Medialab Srl, 2011)

Harris D.A.

;

MINERvA1 Collaboration

The MINERvA experiment, operating since 2009 in the NuMI neutrino beam line at Fermilab, has collected neutrino and antineutrino scattering data on a variety of nuclear targets. The detector is designed to identify events originating in plastic scintillator, lead, carbon, iron, water, and liquid helium. The goal of the experiment is to measure inclusive and exclusive cross sections for neutrino and antineutrino with much greater precision than previous experiments. We present preliminary kinematic distributions for charged current quasi-elastic scattering and other processes. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.

2

Publicación

Phenolic compounds from Andean mashua (Tropaeolum tuberosum) tubers display protection against soybean oil oxidation

(SAGE, 2012)

Betalleluz-Pallardel I.

;

Chirinos R.

;

Rogez H.

;

Pedreschi R.

;

Campos D.

Phenolic compounds from mashua tuber were evaluated as potential antioxidants to retard the oxidation of crude soybean oil submitted to accelerated storage and frying. During the accelerated storage, an ethanolic crude extract, a purified extract, an aqueous fraction and an ethyl acetate fraction from mashua containing different gallic acid equivalent concentrations (100, 300 and 600 ppm) in oil were evaluated at 55 C. After 15 days of storage, better effects were evidenced against soybean oil oxidation at 300 and 600 ppm of ethyl acetate fraction in comparison to 200 ppm butylated hydroxytoluene and the control (no antioxidant added). During the frying process at 180 C, principal component analysis revealed that the content of trienes and dienes were strongly correlated with the frying batch. Ethyl acetate fraction at 200 ppm showed the highest efficacy against oil oxidation in terms of polar compound values, free fatty acids and conjugated dienes and trienes in comparison to the oil containing 200 ppm tert-butylhydroquinone and control. Differential scanning calorimetry corroborated the efficacy of ethyl acetate fraction phenolic and it is strongly recommended as method for validation of results. This study provides strong evidence related to the excellent protective effects against soybean oil oxidation of mashua phenolics. This crop could be utilized as an alternative source of natural antioxidants by the oil industry

21

Publicación

Arachne-A web-based event viewer for MINERνA

(Elsevier B.V., 2012)

Tagg N.

;

Brangham J.

;

Chvojka J.

;

Clairemont M.

;

Day M.

;

Eberly B.

;

Felix J.

;

Fields L.

;

Gago A.M.

;

Gran R.

;

Harris D.A.

;

Kordosky M.

;

Lee H.

;

Maggi G.

;

Maher E.

;

Mann W.A.

;

Marshall C.M.

;

McFarland K.S.

;

McGowan A.M.

;

Mislivec A.

;

Mousseau J.

;

Osmanov B.

;

Osta J.

;

Paolone V.

;

Perdue G.

;

Ransome R.D.

;

Ray H.

;

Schellman H.

;

Schmitz D.W.

;

Simon C.

;

Solano Salinas C.J.

;

Tice B.G.

;

Walding J.

;

Walton T.

;

Wolcott J.

;

Zhang D.

;

Ziemer B.P.

Neutrino interaction events in the MINERνA detector are visually represented with a web-based tool called Arachne. Data are retrieved from a central server via AJAX, and client-side JavaScript draws images into the users browser window using the draft HTML 5 "standard". These technologies allow neutrino interactions to be viewed by anyone with a web browser, allowing for easy hand-scanning of particle interactions. Arachne has been used in MINERνA to evaluate neutrino data in a prototype detector, to tune reconstruction algorithms, and for public outreach and education. © 2012 Published by Elsevier B.V.

8

Publicación

Arachne-A web-based event viewer for MINERvA

(Elsevier B.V., 2012)

Tagg, N

;

Brangham, J

;

Chvojka, J

;

Clairemont, M

;

Day, M

;

Eberly, B

;

Felix, J

;

Fields, L

;

Gago, AM

;

Gran, R

;

Harris, DA

;

Kordosky, M

;

Lee, H

;

Maggi, G

;

Maher, E

;

Mann, WA

;

Marshall, CM

;

McFarland, KS

;

McGowan, AM

;

Mislivec, A

;

Mousseau, J

;

Osmanov, B

;

Osta, J

;

Paolone, V

;

Perdue, G

;

Ransome, RD

;

Ray, H

;

Schellman, H

;

Schmitz, DW

;

Simon, C

;

Salinas, CJS

;

Tice, BG

;

Walding, J

;

Walton, T

;

Wolcott, J

;

Zhang, D

;

Ziemer, BP

Neutrino interaction events in the detector are visually represented with a web-based tool called Arachne. Data are retrieved from a central server via AJAX, and client-side JavaScript draws images into the user's browser window using the draft HTML 5 standard. These technologies allow neutrino interactions to be viewed by anyone with a web browser, allowing for easy hand-scanning of particle interactions. Arachne has been used in to evaluate neutrino data in a prototype detector, to tune reconstruction algorithms, and for public outreach and education.

5

Publicación

The Design and Performance of the MINERνA Experiment

(Elsevier, 2012)

Budd H.S.

The design of the MINERνA detector is presented. We give an overview of the detector. We describe the optical system, giving details on the scintillator, the optical cabling and fibers, the PMTs, and the PMT housing. We give details on the electronics. We describe the assembled component, called the module, which gets inserted into the detector. We give details on the quality control of the modules and present documentation showing the performance of the detector

6

Publicación

Demonstration of communication using neutrinos

(World Scientific Publishing Co. Pte Ltd, 2012)

Stancil, DD

;

Adamson, P

;

Alania, M

;

Aliaga, L

;

Andrews, M

;

Del Castillo, CA

;

Bagby, L

;

Alba, JLB

;

Bodek, A

;

Boehnlein, D

;

Bradford, R

;

Brooks, WK

;

Budd, H

;

Butkevich, A

;

Caicedo, DAM

;

Capista, DP

;

Castromonte, CM

;

Chamorro, A

;

Charlton, E

;

Christy, ME

;

Chvojka, J

;

Conrow, PD

;

Danko, I

;

Day, M

;

Devan, J

;

Downey, JM

;

Dytman, SA

;

Eberly, B

;

Fein, JR

;

Felix, J

;

Fields, L

;

Fiorentini, GA

;

Gago, AM

;

Gallagher, H

;

Gran, R

;

Grange, J

;

Griffin, J

;

Griffin, T

;

Hahn, E

;

Harris, DA

;

Higuera, A

;

Hobbs, JA

;

Hoffman, CM

;

Hughes, BL

;

Hurtado, K

;

Judd, A

;

Kafka, T

;

Kephart, K

;

Kilmer, J

;

Kordosky, M

;

Kulagin, SA

;

Kuznetsov, VA

;

Lanari, M

;

Le, T

;

Lee, H

;

Loiacono, L

;

Maggi, G

;

Maher, E

;

Manly, S

;

Mann, WA

;

Marshall, CM

;

Mcfarland, KS

;

Mislivec, A

;

Mcgowan, AM

;

Morfin, JG

;

Da Motta, H

;

Mousseau, J

;

Nelson, JK

;

Niemiec-Gielata, JA

;

Ochoa, N

;

Osmanov, B

;

Osta, J

;

Palomino, JL

;

Paradis, JS

;

Paolone, V

;

Park, J

;

Pena, C

;

Perdue, G

;

Lara, CEP

;

Peterman, AM

;

Pla-Dalmau, A

;

Pollock, B

;

Prokoshin, F

;

Ransome, RD

;

Ray, H

;

Reyhan, M

;

Rubinov, P

;

Ruggiero, D

;

Sands, OS

;

Schellman, H

;

Schmitz, DW

;

Schulte, EC

;

Simon, C

;

Salinas, CJS

;

Stefanski, R

;

Stevens, RG

;

Tagg, N

;

Takhistov, V

;

Tice, BG

;

Tilden, RN

;

Velasquez, JP

;

Vergalosova, I

;

Voirin, J

;

Walding, J

;

Walker, BJ

;

Walton, T

;

Wolcott, J

;

Wytock, TP

;

Zavala, G

;

Zhang, D

;

Zhu, LY

;

Ziemer, BP

Beams of neutrinos have been proposed as a vehicle for communications under unusual circumstances, such as direct point-to-point global communication, communication with submarines, secure communications and interstellar communication. We report on the performance of a low-rate communications link established using the NuMI beam line and the MINERvA detector at Fermilab. The link achieved a decoded data rate of 0.1 bits/sec with a bit error rate of 1% over a distance of 1.035 km, including 240 m of earth.

10

Publicación

The influence of geographic heterogeneity in predation pressure on sexual signal divergence in an Amazonian frog species complex

(Oxford University Press, 2013)

Trillo, PA

;

Athanas, KA

;

Goldhill, DH

;

Hoke, KL

;

Funk, WC

Sexual selection plays an important role in mating signal divergence, but geographic variation in ecological factors can also contribute to divergent signal evolution. We tested the hypothesis that geographic heterogeneity in predation causes divergent selection on advertisement call complexity within the Engystomops petersi (previously Physalaemus petersi) frog species complex. We conducted predator phonotaxis experiments at two sites where female choice is consistent with call trait divergence. Engystomops at one site produces complex calls, whereas the closely related species at the other site produces simple calls. Bats approached complex calls more than simple calls at both sites, suggesting selection against complex calls. Moreover, bat predation pressure was greater at the site with simple calls, suggesting stronger selection against complex calls and potentially precluding evolution of complex calls at this site. Our results show that geographic variation in predation may play an important role in the evolution and maintenance of mating signal divergence.

5

Publicación

Implementation of an alternative method to determine the critical cooling rate: Application in silver and copper nanoparticles

(Elsevier, 2014)

Medrano L.R.

;

Landauro C.V.

;

Rojas-Tapia J.

An alternative method to determine the critical cooling rate of materials has been developed by explaining the size and cooling rate dependences of physical properties of metallic nanoparticles through the scaling theory. This method has been applied to silver and copper nanoparticles which have been obtained by molecular dynamics simulations. The results reveal that our values for critical rate are close for each studied physical quantity. Thus, by taking the average among them, we obtain 6.2(8) × 1012 K/s for silver and 8.9(5) × 1012 K/s for copper. We have also found the threshold size of nanoparticle behavior is independent of the cooling rate.

1

Publicación

Oxfendazole flukicidal activity in pigs

(Elsevier, 2014)

Ortiz P.

;

Terrones S.

;

Cabrera M.

;

Hoban C.

;

Ceballos L.

;

Moreno L.

;

Canton C.

;

Donadeu M.

;

Lanusse C.

;

Alvarez L.

Although oxfendazole (OFZ) is a well know broad-spectrum benzimidazole anthelmintic, the assessment of its potential trematodicidal activity remains unexplored. OFZ administration at single high doses has been recommended to control Taenia solium cysticercus in pigs. The current study investigated the flukicidal activity obtained after a single high (30 mg/kg) oral dose of OFZ in pigs harbouring a natural Fasciola hepatica infection. Sixteen (16) local ecotype pigs were randomly allocated into two (2) experimental groups of 8 animals each named as follow: Untreated control and OFZ treated, in which animals received OFZ (Synanthic®, Merial Ltd., 9.06% suspension) orally at 30 mg/kg. At seven (7) days post-treatment, all the animals were sacrificed and direct adult liver fluke counts were performed following the WAAVP guidelines. None of the animals involved in this experiment showed any adverse event during the study. OFZ treatment as a single 30 mg/kg oral dose showed a 100% efficacy against F. hepatica. In conclusion, the trial described here demonstrated an excellent OFZ activity against F. hepatica in naturally infected pigs, after its administration at a single oral dose of 30 mg/kg.

1

Publicación

Design, calibration, and performance of the MINERvA detector

(Pontificia Universidad Católica del Perú, 2014)

Aliaga L.

;

Bagby L.

;

Baldin B.

;

Baumbaugh A.

;

Bodek A.

;

Bradford R.

;

Brooks W.K.

;

Boehnlein D.

;

Boyd S.

;

Budd H.

;

Butkevich A.

;

Martinez Caicedo D.A.

;

Castromonte C.M.

;

Christy M.E.

;

Chvojka J.

;

Da Motta H.

;

Damiani D.S.

;

Danko I.

;

Datta M.

;

Devan J.

;

Draeger E.

;

Dytman S.A.

;

Díaz G.A.

;

Eberly B.

;

Edmondson D.A.

;

Felix J.

;

Fields L.

;

Fiorentini G.A.

;

Flight R.S.

;

Gago A.M.

;

Gallagher H.

;

George C.A.

;

Gielata J.A.

;

Gingu C.

;

Gran R.

;

Grange J.

;

Grossman N.

;

Harris D.A.

;

Heaton J.

;

Higuera A.

;

Hobbs J.A.

;

Howley I.J.

;

Hurtado K.

;

Jerkins M.

;

Kafka T.

;

Kantner M.O.

;

Keppel C.

;

Kilmer J.

;

Kordosky M.

;

Krajeski A.H.

;

Kumbartzki G.J.

;

Lee H.

;

Leister A.G.

;

Locke G.

;

Maggi G.

;

Maher E.

;

Manly S.

;

Mann W.A.

;

Marshall C.M.

;

McFarland K.S.

;

McGivern C.L.

;

McGowan A.M.

;

Mislivec A.

;

Morfín J.G.

;

Mousseau J.

;

Naples D.

;

Nelson J.K.

;

Niculescu G.

;

Niculescu I.

;

O'Connor C.D.

;

Ochoa N.

;

Olsen J.

;

Osmanov B.

;

Osta J.

;

Palomino J.L.

;

Paolone V.

;

Park J.

;

Perdue G.N.

;

Peña C.

;

Pla-Dalmau A.

;

Rakotondravohitra L.

;

Ransome R.D.

;

Ray H.

;

Ren L.

;

Rubinov P.

;

Rude C.

;

Sassin K.E.

;

Schellman H.

;

Schmitz D.W.

;

Schneider R.M.

;

Schulte E.C.

;

Simon C.

;

Snider F.D.

;

Snyder M.C.

;

Solano Salinas C.J.

;

Tagg N.

;

Tice B.G.

;

Tilden R.N.

;

Velásquez J.P.

;

Walton T.

;

Westerberg A.

;

Wolcott J.

;

Wolthuis B.A.

;

Woodward N.

;

Wytock T.

;

Zavala G.

;

Zeng H.B.

;

Zhang D.

;

Zhu L.Y.

;

Ziemer B.P.

The skin is the largest organ of the body that protects it from the external environment. High- frequency ultra sound (HF-US) has been used to visualize the skin in depth and to diagnose some pathologies in dermatological applications. Quantitative ultrasound (QUS) includes several techniques that provide values of particular physical properties. In this thesis work, three QUS parameters are explained and used to characterize healthy skin through HF-US: attenuation coefficient slope (ACS), backscatter coefficient (BSC) and shear wave speed (SWS). They were estimated with the regularized spectral-log difference (RSLD) method, the reference phan- tom method, and the crawling wave sonoelastography method, respectively. All the three parameters were assessed in phantoms, ex vivo and in vivo skin. In calibrated phantoms, RSLD showed a reduc- tion of up to 93% of the standard deviation concerning the estimation with SLD, and BSC showed an agreement with the Faran’s theoretical curve. In gelatin-based phantoms, surface acoustic waves (SAWs) were estimated in two interfaces: solid-water and solid-US gel, which all owed corroborating SAWs presence and finding an empirical compensation factor when the coupling interface is US gel. A correction factor of 0:97 for SAW-to-shear was found to avoid underestimation in phantoms. Porcine thigh was calculated in the range from 8 to 27 MHz, where the ACS was 4:08 _+_0:43 dB cm -1 MHz-1 and BSC was in the range from 10 1 to 10° sr-1 _cm-1. Crawling wave sonoelastography method was applied for the vibration frequencies between 200 Hz and 800 Hz, where SWS was in the range from 4:6 m/sto9:1 m/s. In vivo ACS and BSC were assessed in the healthy forearm and thigh, whereas SWS only in the thigh. The average ACS in the forearm dermis was 2.07dB cm-1 _MHz-1, which is in close agreement with the literature. A significant difference (p < 0.05) was found between the ACS in the forearm dermis and the thigh dermis (average ACS of 2.54dB cm-1 _MHz-1). The BSC of the forearm and thigh dermis were in the range from 10 -1 to 10° sr-1 _cm-1, and in the range from 10-1 to 10° sr-1 _cm-1, respectively. The SWS in the thigh dermis was 2:4 _+_0:38 m/s for a vibration frequency of 200Hz, with an increasing trend as frequency increases. Results suggest that these QUS parameters have the potential to be used as a tool for in vivo skin characterization and show potential for future application in skin lesions.

4

Publicación

Determination of the threshold of nanoparticle behavior: Structural and electronic properties study of nano-sized copper

(Elsevier B.V., 2014)

Torres-Vega J.J.

;

Medrano L.R.

;

Landauro C.V.

;

Rojas-Tapia J.

In the present work we determine the threshold of the nanoparticle behavior of copper nanoparticles by studying their structural and electronic properties. The studied nanoparticles contain from 13 to 8217 atoms and were obtained by molecular dynamics simulations using the Johnson potential for copper based on the embedded atom method. The results indicate that for small copper nanoparticles (o1000 atoms, 2.8 nm) the surface plays an important role in their physical properties. Whereas, for large nanoparticles (42000 atoms, 3.5 nm), with spherical-like external shape and large percentage of fcc-like local structure, this effect is negligible and their electronic character are similar to such expected in solid copper. Finally, it has also been shown that copper nanoparticles change their electronic character, from metallic to insulating, after increasing the strength of the chemical disorder.

4

Publicación

MINERvA neutrino detector response measured with test beam data

(Elsevier, 2015)

Aliaga L.

;

Altinok O.

;

Araujo Del Castillo C.

;

Bagby L.

;

Bellantoni L.

;

Bergan W.F.

;

Bodek A.

;

Bradford R.

;

Bravar A.

;

Budd H.

;

Butkevich A.

;

Martinez Caicedo D.A.

;

Carneiro M.F.

;

Christy M.E.

;

Chvojka J.

;

Da Motta H.

;

Devan J.

;

Díaz G.A.

;

Dytman S.A.

;

Eberly B.

;

Felix J.

;

Fields L.

;

Fine R.

;

Flight R.

;

Gago A.M.

;

Gingu C.

;

Golan T.

;

Gomez A.

;

Gran R.

;

Harris D.A.

;

Higuera A.

;

Howley I.J.

;

Hurtado K.

;

Kleykamp J.

;

Kordosky M.

;

Lanari M.

;

Le T.

;

Leister A.J.

;

Lovlein A.

;

Maher E.

;

Mann W.A.

;

Marshall C.M.

;

McFarland K.S.

;

McGivern C.L.

;

McGowan A.M.

;

Messerly B.

;

Miller J.

;

Miller W.

;

Mislivec A.

;

Morfín J.G.

;

Mousseau J.

;

Muhlbeier T.

;

Naples D.

;

Nelson J.K.

;

Norrick A.

;

Ochoa N.

;

O'Connor C.D.

;

Osmanov B.

;

Osta J.

;

Paolone V.

;

Patrick C.E.

;

Patrick L.

;

Perdue G.N.

;

Pérez Lara C.E.

;

Rakotondravohitra L.

;

Ray H.

;

Ren L.

;

Rodrigues P.A.

;

Rubinov P.

;

Rude C.R.

;

Ruterbories D.

;

Schellman H.

;

Schmitz D.W.

;

Solano Salinas C.J.

;

Tagg N.

;

Tice B.G.

;

Urrutia Z.

;

Valencia E.

;

Walton T.

;

Westerberg A.

;

Wolcott J.

;

Woodward N.

;

Wospakrik M.

;

Zavala G.

;

Zhang D.

;

Ziemer B.P.

The MINERvA collaboration operated a scaled-down replica of thesolid scintillator tracking and sampling calorimeter regions of the MINERvA detector in a hadron test beam at the Fermilab Test Beam Facility. This paper reports measurements with samples of protons, pions, and electrons from 0.35 to 2.0 GeV/c momentum. The calorimetric response to protons, pions, and electrons is obtained from these data. A measurement of the parameter in Birks' law and an estimate of the tracking efficiency are extracted from the proton sample. Overall the data are well described by a Geant4-based Monte Carlo simulation of the detector and particle interactions with agreements better than 4% for the calorimetric response, though some features of the data are not precisely modeled. These measurements are used to tune the MINERvA detector simulation and evaluate systematic uncertainties in support of the MINERvA neutrino crosssection measurement program.

4

Publicación

Single neutral pion production by charged-current ν-μ interactions on hydrocarbon at 〈Eν〉=3.6 GeV

(Elsevier, 2015)

Le T.

;

Palomino J.L.

;

Aliaga L.

;

Altinok O.

;

Bercellie A.

;

Bodek A.

;

Bravar A.

;

Brooks W.K.

;

Butkevich A.

;

Martinez Caicedo D.A.

;

Carneiro M.F.

;

Christy M.E.

;

Chvojka J.

;

da Motta H.

;

Devan J.

;

Dytman S.A.

;

Díaz G.A.

;

Eberly B.

;

Felix J.

;

Fields L.

;

Fine R.

;

Gago A.M.

;

Gallagher H.

;

Gran R.

;

Harris D.A.

;

Higuera A.

;

Hurtado K.

;

Kordosky M.

;

Maher E.

;

Manly S.

;

Mann W.A.

;

Marshall C.M.

;

McFarland K.S.

;

McGivern C.L.

;

McGowan A.M.

;

Miller J.

;

Morfín J.G.

;

Mousseau J.

;

Nelson J.K.

;

Norrick A.

;

Osta J.

;

Paolone V.

;

Park J.

;

Patrick C.E.

;

Perdue G.N.

;

Rakotondravohitra L.

;

Ransome R.D.

;

Ray H.

;

Ren L.

;

Rodrigues P.A.

;

Ruterbories D.

;

Schellman H.

;

Schmitz D.W.

;

Sobczyk J.T.

;

Solano Salinas C.J.

;

Tagg N.

;

Tice B.G.

;

Valencia E.

;

Walton T.

;

Wolcott J.

;

Yepes-Ramirez H.

;

Zavala G.

;

Zhang D.

;

Ziemer B.P.

Single neutral pion production via muon antineutrino charged-current interactions in plastic scintillator (CH) is studied using the MINERvA detector exposed to the NuMI low-energy, wideband antineutrino beam at Fermilab. Measurement of this process constrains models of neutral pion production in nuclei, which is important because the neutral-current analog is a background for appearance oscillation experiments. The differential cross sections for momentum and production angle, for events with a single observed and no charged pions, are presented and compared to model predictions. These results comprise the first measurement of the kinematics for this process.

7

Publicación

Measurement of muon plus proton final states in nu(mu) interactions on hydrocarbon at < E-nu >=4.2 GeV

(American Physical Society, 2015)

Walton, T

;

Betancourt, M

;

Aliaga, L

;

Altinok, O

;

Bodek, A

;

Bravar, A

;

Budd, H

;

Bustamante, MJ

;

Butkevich, A

;

Caicedo, DAM

;

Carneiro, MF

;

Castromonte, CM

;

Christy, ME

;

Chvojka, J

;

da Motta, H

;

Datta, M

;

Devan, J

;

Dytman, SA

;

Diaz, GA

;

Eberly, B

;

Felix, J

;

Fields, L

;

Fine, R

;

Fiorentini, GA

;

Gago, AM

;

Gallagher, H

;

Gran, R

;

Harris, DA

;

Higuera, A

;

Hurtado, K

;

Kleykamp, J

;

Kordosky, M

;

Kulagin, SA

;

Le, T

;

Maher, E

;

Manly, S

;

Mann, WA

;

Marshall, CM

;

Mari, CM

;

McFarland, KS

;

McGivern, CL

;

McGowan, AM

;

Messerly, B

;

Miller, J

;

Mislivec, A

;

Morfin, JG

;

Mousseau, J

;

Muhlbeier, T

;

Naples, D

;

Nelson, JK

;

Norrick, A

;

Osta, J

;

Paolone, V

;

Park, J

;

Patrick, CE

;

Perdue, GN

;

Rakotondravohitra, L

;

Ransome, RD

;

Ray, H

;

Ren, L

;

Rodrigues, PA

;

Ruterbories, D

;

Schellman, H

;

Schmitz, DW

;

Simon, C

;

Snider, FD

;

Sobczyk, JT

;

Salinas, CJS

;

Tagg, N

;

Tice, BG

;

Valencia, E

;

Wolcott, J

;

Wospakrik, M

;

Zavala, G

;

Zhang, D

;

Ziemer, BP

A study of charged-current muon neutrino scattering on hydrocarbon (CH) in which the final state includes a muon, at least one proton, and no pions is presented. Although this signature has the topology of neutrino quasielastic scattering from neutrons, the event sample contains contributions from quasielastic and inelastic processes where pions are absorbed in the nucleus. The analysis accepts events with muon production angles up to 70◦ and proton kinetic energies greater than 110 MeV. The cross section, when based completely on hadronic kinematics, is well-described by a relativistic Fermi gas nuclear model including the neutrino event generator modeling for inelastic processes and particle transportation through the nucleus. This is in contrast to the quasielastic cross section based on muon kinematics, which is best described by an extended model that incorporates multi-nucleon correlations. This measurement guides the formulation of a complete description of neutrino-nucleus interactions that encompasses the hadronic as well as the leptonic aspects of this process.

9

Publicación

Neutrino interactions on nuclei at MINERvA

(Editrice Compositori s.r.l., 2015)

Carneiro, MF

Here we present analysis results from the MINERvA experiment for scattering of neutrinos on nucleus in an energy region of few GeV. These results cover a plethora of processes important for high precision neutrino oscillation measurements in which recent results have suggested that the currently used models are insufficient.

9

Publicación

Fascioliasis in schoolchildren in the inter andean valley of Cajamarca, Peru

(WAAVP 2015, 2015-08)

Rodríguez Ulloa, Claudia Rivera-Jacinto, Marco Hobán Vergara, Cristian Del Valle Mendoza, Juana Mercedes Ortiz Oblitas, Pedro

Fascioliasis, caused by Fasciola hepatica, is a public health problem in Peru, especially in schoolchildren. Prevalence rates in livestock are over 80% in dairy cattle reared in the Andean valley of Cajamarca, Peru. The present investigation aimed to determine the prevalence of F. hepatica infection in schoolchildren and the main risk factors involved in its presentation. Two hundred and seventy schoolchildren nine years old and over from primary public institutions from the district of Los Baños del Inca (Cajamarca) were included in the investigation. Questionnaires were applied to parents and children and fecal samples were taken and evaluated using the rapid sedimentation technique. Blood samples were also collected and analyzed. Seventeen fecal samples were positive to F. hepatica eggs, giving a prevalence of 6.3% (95% CI 3.21 - 9.38). Significant differences were found with origin of the child, history of intestinal parasitism, and the habit of chewing grass (p< 0.05). The rural origin (OR 4.8, 95% CI: 1.53-15.08) and the habit of chewing grass (OR 3.26, CI: 95% 1.07 - 9.96) were the most likely risk factors associated with the acquisition of infection. The leukocyte count of infected children varied between 3900 and 10580 cells /mm3 (mean ± SD = 6458.3 ± 2080.3). Thirty three percent of children positive to F. hepatica eggs presented eosinophilia. We conclude that the prevalence of human fascioliasis in the district of Los Baños del Inca is at the mesoendemic level and rurality provides conditions for acquiring the infection.

15

Publicación

Measurement of neutrino flux from neutrino-electron elastic scattering

(American Physical Society, 2016)

Park J.

;

Aliaga L.

;

Altinok O.

;

Bellantoni L.

;

Bercellie A.

;

Betancourt M.

;

Bodek A.

;

Bravar A.

;

Budd H.

;

Cai T.

;

Carneiro M.F.

;

Christy M.E.

;

Chvojka J.

;

Da Motta H.

;

Dytman S.A.

;

Díaz G.A.

;

Eberly B.

;

Felix J.

;

Fields L.

;

Fine R.

;

Gago A.M.

;

Galindo R.

;

Ghosh A.

;

Golan T.

;

Gran R.

;

Harris D.A.

;

Higuera A.

;

Kleykamp J.

;

Kordosky M.

;

Le T.

;

Maher E.

;

Manly S.

;

Mann W.A.

;

Marshall C.M.

;

Martinez Caicedo D.A.

;

McFarland K.S.

;

McGivern C.L.

;

McGowan A.M.

;

Messerly B.

;

Miller J.

;

Mislivec A.

;

Morfín J.G.

;

Mousseau J.

;

Naples D.

;

Nelson J.K.

;

Norrick A.

;

Nuruzzaman

;

Osta J.

;

Paolone V.

;

Patrick C.E.

;

Perdue G.N.

;

Rakotondravohitra L.

;

Ramirez M.A.

;

Ray H.

;

Ren L.

;

Rimal D.

;

Rodrigues P.A.

;

Ruterbories D.

;

Schellman H.

;

Solano Salinas C.J.

;

Tagg N.

;

Tice B.G.

;

Valencia E.

;

Walton T.

;

Wolcott J.

;

Wospakrik M.

;

Zavala G.

;

Zhang D.

Muon-neutrino elastic scattering on electrons is an observable neutrino process whose cross section is precisely known. Consequently a measurement of this process in an accelerator-based νμ beam can improve the knowledge of the absolute neutrino flux impinging upon the detector; typically this knowledge is limited to ∼10% due to uncertainties in hadron production and focusing. We have isolated a sample of 135±17 neutrino-electron elastic scattering candidates in the segmented scintillator detector of MINERvA, after subtracting backgrounds and correcting for efficiency. We show how this sample can be used to reduce the total uncertainty on the NuMI νμ flux from 9% to 6%. Our measurement provides a flux constraint that is useful to other experiments using the NuMI beam, and this technique is applicable to future neutrino beams operating at multi-GeV energies. © 2016 American Physical Society.

5

Publicación

Síntesis y aplicación de catalizadores basados en óxidos de Mn, Cu, Pr, Ce para la eliminación de N-Hexano

(Universidad Nacional de Ingeniería, 2016)

Zavala Inga, César Humberto

La eliminación total de compuestos orgánicos volátiles (COV’s) altamente tóxicos sin formación de contaminantes secundarios requiere de tecnologías altamente eficientes que garanticen su remoción a la menor temperatura posible con el subsiguiente ahorro energético. La combustión catalítica es una alternativa eficiente para el tratamiento de estos contaminantes frente a la incineración térmica pues opera a temperaturas por debajo de 400 ºC, evitando la formación de NOx. Este trabajo ha perseguido el desarrollo de catalizadores activos, térmicamente estables, selectivos a generar CO2 y económico para la combustión total de n-hexano en concentraciones habituales en emisiones gaseosas de la industria (concentración inicial 2000 ppmV). El n-hexano se ha seleccionado como molécula modelo por ser un solvente de alta difusión en la industria de pinturas, lacas y petroquímica. Para cumplir su propósito, en este trabajo se han preparado catalizadores basados en Ce-Mn, Cu-Mn y Ce-Pr para la combustión de n-hexano para estudiar las condiciones experimentales preliminares para la formación de la fases activa que asegure la formación de una alta área superficial, estabilidad térmica y la presencia de sitios selectivos a productos de combustión total. La síntesis de los catalizadores de Ce-Mn se ha realizado mediante coprecipitación que consiste básicamente en la adición gradual del agente precipitante (solución de carbonato de sodio) a la mezcla de igual volumen de las soluciones metálicas con la concentración adecuada (preparadas a partir de precursores nitrato) hasta el pH correspondiente a la precipitación total. Luego de emplear diferentes tiempos de envejecimiento (4, 18 y 24h) se secó a 120 °C por 24 h y haciendo una rampa de calentamiento de 2oC/min se calcinó en 2 etapas: primero a 250 ºC durante 2 h, y luego a 500 ºC durante 3 h. La síntesis de los catalizadores de Cu-Mn ha sido preparados utilizando el método de autocombustión utilizando ácido cítrico (CIT) y etilenglicol (EG) como agentes de combustión en distintos casos; en cada caso se han formado complejos orgánicos que después de la calcinación se han obtenido los óxidos metálicos. La síntesis de los catalizadores de Ce-Pr fueron preparados por coprecipitación convencional usando amoniaco como agente precipitante. Adicionalmente, en todos los casos, los óxidos simples fueron preparados aplicando el mismo procedimiento que sus análogos mixtos, por razones de comparación. La caracterización de los catalizadores se realizó utilizando las siguientes técnicas: adsoción-desorción de N2 (técnica BET), difracción de rayos X (XRD), análisis termogravimétrico (TGA), reducción a temperatura programada (TPR) y espectroscopía fotoelectrónica de rayos X (XPS). Todos los sólidos sintetizados tuvieron textura mesoporosas; las superficies específicas en caso de las muestras de Ce-Mn mejoraron con el tiempo de envejecimiento. Los catalizadores basados en Ce-Mn y Ce-Pr tienen la forma cristalina tipo fluorita mientras que Cu-Mn la forma cristalina tipo hopcalita. La evaluación de la actividad de los catalizadores se realizó mediante la medición de las curvas de ignición en la combustión de n-hexano. Los testeos catalíticos se realizaron en un reactor de lecho fijo, empleando una concentración inicial de alcano de 2000 ppmV y una velocidad espacial másica por hora (WHSV) de 80 h-1. Las actividades catalíticas de las muestras de óxidos mixtos de Ce-Mn fueron más altas que sus homólogos simples. La muestra Ce0.67Mn0.33O2 con tiempo de envejecimiento de 24h ha mostrado el mejor rendimiento probablemente debido a la presencia de sitios de defectos vacantes promocionados por la incorporación de especies de MnOx en la estructura de CeO2, la mayor reducibilidad y la mayor área específica. Las muestras mixtas de Ce-Mn han mostrado estabilidad térmica en contraste con el óxido de manganeso en el que solo se observó una reducción en su área superficial. Las curvas de actividad de los catalizadores del sistema Cu-Mn fueron medidas en función a su velocidad especifica (moles convertidos de COV’s por hora para una superficie específica de SBET m2 por gramo de catalizador), donde se observó que los catalizadores mixtos con mayor contenido en Mn fueron los más activos; adicionalmente, la muestra preparada de Cu1-Mn3; utilizando el ácido cítrico como agente combustor, presentó mayor actividad comparada con la obtenida con los óxidos simples, y esto se debe probablemente a una mejor superficie específica y una estructura cristalina espinela-hopcalita obtenida. Con el óxido Ce0.9Pr0.1O2 se obtuvo la más alta velocidad específica con un valor de 32.2mmol.m2/g, comparada con las correspondientes a la de otros óxidos mixtos y óxidos simples puros como resultado de una mayor superficie específica obtenida. Finalmente, se comprobó que los catalizadores basados en Ce-Mn siguió una cinética de pseudo primer orden y que el modelo de Langmuir-Hinshelwood se ajustó bien los datos experimentales según el criterio de selección de modelos (MSC) de Akaike y cuya expresión final de la velocidad de desaparición de n-hexano calculada a la temperatura de 170°C según este modelo es 1.3x10-8 xCn-hexano/(1+12.5xCn-hexano)2.

25

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