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1. Design, characterization and installation of the NEXT-100 cathode and electroluminescence regions

Author

NEXT Collaboration, Mistry, K., Rogers, L., Jones, B. J. P., Munson, B., Norman, L., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Auria-Luna, F., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., del Barrio-Torregrosa, M., Bayo, A., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Brodolin, A., Byrnes, N., Cárcel, S., Castillo, A., Cebrián, S., Church, E., Cid, L., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Echevarria, C., Elorza, M., Escada, J., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Gómez-Cadenas, J. J., González, R., Grocott, J. W. R., Guenette, R., Hafidi, K., Hauptman, J., Henriques, C. A. O., Hernando~Morata, J. A., Herrero-Gómez, P., Herrero, V., Carrete, C. Hervés, Ifergan, Y., Larizgoitia, L., Larumbe, A., Lebrun, P., Lopez, F., López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Miller, R. L., Molina-Canteras, J., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Navarro, K. E., Novella, P., Nuñez, A., Nygren, D. R., Oblak, E., Oliver, D., Palacio, J., Palmeiro, B., Para, A., Parmaksiz, I., Pelegrin, J., Maneiro, M. Pérez, Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rogero, C., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Seemann, M., Shomroni, I., Simón, A., Soleti, S. R., Sorel, M., Soto-Oton, J., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Trettin, A., Usón, A., Veloso, J. F. C. A., Waiton, J., and Yubero, A.

Subjects
Physics - Instrumentation and Detectors
Abstract

NEXT-100 is currently being constructed at the Laboratorio Subterr\'aneo de Canfranc in the Spanish Pyrenees and will search for neutrinoless double beta decay using a high-pressure gaseous time projection chamber (TPC) with 100 kg of xenon. Charge amplification is carried out via electroluminescence (EL) which is the process of accelerating electrons in a high electric field region causing secondary scintillation of the medium proportional to the initial charge. The NEXT-100 EL and cathode regions are made from tensioned hexagonal meshes of 1 m diameter. This paper describes the design, characterization, and installation of these parts for NEXT-100. Simulations of the electric field are performed to model the drift and amplification of ionization electrons produced in the detector under various EL region alignments and rotations. Measurements of the electrostatic breakdown voltage in air characterize performance under high voltage conditions and identify breakdown points. The electrostatic deflection of the mesh is quantified and fit to a first-principles mechanical model. Measurements were performed with both a standalone test EL region and with the NEXT-100 EL region before its installation in the detector. Finally, we describe the parts as installed in NEXT-100, following their deployment in Summer 2023., Comment: 35 pages, 25 Figures, update includes accepted version in JINST

Published
2023
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2. Demonstration of Event Position Reconstruction based on Diffusion in the NEXT-White Detector

Author

Haefner, J., Navarro, K. E., Guenette, R., Jones, B. J. P., Tripathi, A., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Auria-Luna, F., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., del Barrio-Torregrosa, M., Bayo, A., BenllochRodríguez, J. M., Borges, F. I. G. M., Brodolin, A., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Cid, L., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Elorza, M., Escada, J., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Carrete, C. Hervés, Ifergan, Y., Labarga, L., Larizgoitia, L., Larumbe, A., Lebrun, P., Lopez, F., López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Miller, R. L., Mistry, K., Molina-Canteras, J., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nuñez, A., Nygren, D. R., Oblak, E., Palacio, J., Palmeiro, B., Para, A., Parmaksiz, I., Pelegrin, J., Maneiro, M. Pérez, Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Shomroni, I., Simón, A., Soleti, S. R., Sorel, M., Soto-Oton, J., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Trettin, A., Usón, A., Veloso, J. F. C. A., Waiton, J., and White, J. T.

Subjects
High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

Noble element time projection chambers are a leading technology for rare event detection in physics, such as for dark matter and neutrinoless double beta decay searches. Time projection chambers typically assign event position in the drift direction using the relative timing of prompt scintillation and delayed charge collection signals, allowing for reconstruction of an absolute position in the drift direction. In this paper, alternate methods for assigning event drift distance via quantification of electron diffusion in a pure high pressure xenon gas time projection chamber are explored. Data from the NEXT-White detector demonstrate the ability to achieve good position assignment accuracy for both high- and low-energy events. Using point-like energy deposits from $^{83\mathrm{m}}$Kr calibration electron captures ($E\sim45$keV), the position of origin of low-energy events is determined to $2~$cm precision with bias $< 1$mm. A convolutional neural network approach is then used to quantify diffusion for longer tracks (E$\geq$1.5MeV), yielding a precision of 3cm on the event barycenter. The precision achieved with these methods indicates the feasibility energy calibrations of better than 1% FWHM at Q$_{\beta\beta}$ in pure xenon, as well as the potential for event fiducialization in large future detectors using an alternate method that does not rely on primary scintillation., Comment: 18 pages, 16 figures

Published
2023

3. Demonstration of neutrinoless double beta decay searches in gaseous xenon with NEXT

Author

NEXT Collaboration, Novella, P., Sorel, M., Usón, A., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Auria-Luna, F., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., del Barrio-Torregrosa, M., Bayo, A., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Cid, L., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Elorza, M., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Guenette, R., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Carrete, C. Hervés, Ho, J., Ho, P., Ifergan, Y., Jones, B. J. P., Labarga, L., Larizgoitia, L., Larumbe, A., Lebrun, P., Lopez, F., Gutierrez, D. Lopez, López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Miller, R. L., Mistry, K., Molina-Canteras, J., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Navarro, K. E., Nuñez, A., Nygren, D. R., Oblak, E., Odriozola-Gimeno, M., Palacio, J., Palmeiro, B., Para, A., Parmaksiz, I., Pelegrin, J., Maneiro, M. Pérez, Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Soleti, S. R., Stanford, C., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Veloso, J. F. C. A., Vuong, T. T., Waiton, J., and White, J. T.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

The NEXT experiment aims at the sensitive search of the neutrinoless double beta decay in $^{136}$Xe, using high-pressure gas electroluminescent time projection chambers. The NEXT-White detector is the first radiopure demonstrator of this technology, operated in the Laboratorio Subterr\'aneo de Canfranc. Achieving an energy resolution of 1% FWHM at 2.6 MeV and further background rejection by means of the topology of the reconstructed tracks, NEXT-White has been exploited beyond its original goals in order to perform a neutrinoless double beta decay search. The analysis considers the combination of 271.6 days of $^{136}$Xe-enriched data and 208.9 days of $^{136}$Xe-depleted data. A detailed background modeling and measurement has been developed, ensuring the time stability of the radiogenic and cosmogenic contributions across both data samples. Limits to the neutrinoless mode are obtained in two alternative analyses: a background-model-dependent approach and a novel direct background-subtraction technique, offering results with small dependence on the background model assumptions. With a fiducial mass of only 3.50$\pm$0.01 kg of $^{136}$Xe-enriched xenon, 90% C.L. lower limits to the neutrinoless double beta decay are found in the T$_{1/2}^{0\nu}>5.5\times10^{23}-1.3\times10^{24}$ yr range, depending on the method. The presented techniques stand as a proof-of-concept for the searches to be implemented with larger NEXT detectors.

Published
2023
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4. Assessment of the ecotoxicity of extracts from sugarcane bagasse biochars activated with zinc chloride

Author

Júlia Martins Carolino, Gabrielle Schultz Braz, Jaqueline do Carmo Lima Carvalho, Filipe Gomes Fagundes, Pablo Aislan Freitas e Silva, Isis Orika Hernandez Rocha, Marina Costa Patrocínio, Evaneide Nascimento Lima, Robson Pereira de Lima, Magno André de Oliveira, Augusto César da Silva Bezerra, Osania Emerenciano Ferreira, and Alan Rodrigues Teixeira Machado

Subjects
Biomass, Waste, Charcoal, Environment, Crustacean, Environmental technology. Sanitary engineering, TD1-1066
Abstract

Biochar derived from the pyrolysis of biomass is recognized for its carbon sequestration capacity. By adding physical or chemical activation steps, its properties can be enhanced, resulting in activated or modified biochar. However, investigating the possible toxic effects for safer application is necessary. In this study, we aimed to assess the ecotoxicological effects of extracts from biochars prepared from sugarcane bagasse activated with zinc chloride and heat treated at temperatures ranging from 300 to 1000 °C. Using Artemia salina as an indicator of toxicity, we observed variation in mortality ranging from 27.5 % to 100 % as the temperature varied between 1000 and 300 °C. The leachate from the sample prepared at 300 °C, which had the highest zinc content, presented an LC50 of 0.53 w/v. Phytotoxicity tests with Lactuca sativa revealed that extracts from biochars prepared at lower temperatures presented greater phytotoxicity, with reductions in relative germination, relative average radicle growth and the germination index. These results highlight the need to assess the ecotoxicological risks of activated biochar with zinc chloride. The sensitivities of Artemia salina and Lactuca sativa are promising for detecting these effects, suggesting that they are effective approaches for assessing environmental safety. These findings not only broaden our understanding of the adverse effects of activated biochar but also guide safe and sustainable practices for its future application.

Published
2025
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5. NEXT-CRAB-0: A High Pressure Gaseous Xenon Time Projection Chamber with a Direct VUV Camera Based Readout

Author

NEXT Collaboration, Byrnes, N. K., Parmaksiz, I., Adams, C., Asaadi, J., Baeza-Rubio, J, Bailey, K., Church, E., González-Díaz, D., Higley, A., Jones, B. J. P., Mistry, K., Moya, I. A., Nygren, D. R., Oyedele, P., Rogers, L., Stogsdill, K., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Ayet, S., Azevedo, C. D. R., Ballester, F., del Barrio-Torregrosa, M., Bayo, A., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Cárcel, S., Carrión, J. V., Cebrián, S., Cid, L., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Elorza, M., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Guenette, R., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Carrete, C. Hervés, Ho, J., Ho, P., Ifergan, Y., Labarga, L., Larizgoitia, L., Lebrun, P., Lopez, F, Gutierrez, D. Lopez, López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Miller, R. L., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Navarro, K. E., Novella, P., Nuñez, A., Oblak, E., Odriozola-Gimeno, M., Palacio, J., Palmeiro, B., Para, A., Pelegrin, J, Maneiro, M. Pérez, Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Soleti, S. R., Sorel, M., Stanford, C., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Vuong, T. T., Waiton, J., and White, J. T.

Subjects
Physics - Instrumentation and Detectors
Abstract

The search for neutrinoless double beta decay ($0\nu\beta\beta$) remains one of the most compelling experimental avenues for the discovery in the neutrino sector. Electroluminescent gas-phase time projection chambers are well suited to $0\nu\beta\beta$ searches due to their intrinsically precise energy resolution and topological event identification capabilities. Scalability to ton- and multi-ton masses requires readout of large-area electroluminescent regions with fine spatial resolution, low radiogenic backgrounds, and a scalable data acquisition system. This paper presents a detector prototype that records event topology in an electroluminescent xenon gas TPC via VUV image-intensified cameras. This enables an extendable readout of large tracking planes with commercial devices that reside almost entirely outside of the active medium.Following further development in intermediate scale demonstrators, this technique may represent a novel and enlargeable method for topological event imaging in $0\nu\beta\beta$., Comment: 30 Pages, 22 figures, Updated to match current JINST submission

Published
2023

6. A Compact Dication Source for Ba$^{2+}$ Tagging and Heavy Metal Ion Sensor Development

Author

Navarro, K. E., Jones, B. J. P., Baeza-Rubio, J., Boyd, M., Denisenko, A. A., Foss, F. W., Giri, S., Miller, R., Nygren, D. R., Tiscareno, M. R., Samaniego, F. J., Stogsdill, K., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Guenette, R., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Carrete, C. Hervés, Ho, J., Ho, P., Ifergan, Y., Labarga, L., Larizgoitia, L., Lebrun, P., Gutierrez, D. Lopez, López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Mistry, K., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nuñez, A., Oblak, E., Odriozola-Gimeno, M., Palmeiro, B., Para, A., Pelegrín, J., Maneiro, M. Pérez, Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sorel, M., Stanford, C., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Vuong, T. T., Waiton, J., and White, J. T.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract

We present a tunable metal ion beam that delivers controllable ion currents in the picoamp range for testing of dry-phase ion sensors. Ion beams are formed by sequential atomic evaporation and single or multiple electron impact ionization, followed by acceleration into a sensing region. Controllability of the ionic charge state is achieved through tuning of electrode potentials that influence the retention time in the ionization region. Barium, lead, and cobalt samples have been used to test the system, with ion currents identified and quantified using a quadrupole mass analyzer. Realization of a clean $\mathrm{Ba^{2+}}$ ion beam within a bench-top system represents an important technical advance toward the development and characterization of barium tagging systems for neutrinoless double beta decay searches in xenon gas. This system also provides a testbed for investigation of novel ion sensing methodologies for environmental assay applications, with dication beams of Pb$^{2+}$ and Cd$^{2+}$ also demonstrated for this purpose.

Published
2023
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7. Post-consumer high-density polyethylene matrix reinforced by sugarcane bagasse fibers treated in stearic acid solution

Author

Saymon da Silva Almeida, Júlia Audrem Gomes de Oliveira, Mayara de Freitas e Castro, David Coverdale Rangel Velasco, Felipe Perisse Duarte Lopes, Sergio Neves Monteiro, and Djalma Souza

Subjects
Polymeric waste, Lignocellulosic fibers, Solid waste, Polymeric composites, Recycling, Chemical treatments, Mining engineering. Metallurgy, TN1-997
Abstract

The study aimed to advance composite technology by exploring the potential of recycled materials, specifically high-density polyethylene (HDPE) composites reinforced with sugarcane bagasse fibers. This research not only addresses environmental concerns by utilizing recyclable materials but also aims to offer significant technical, economic, and social advantages. The investigation focused on formulating and evaluating these composites, considering varying proportions of untreated sugarcane bagasse fibers and examining the effects of chemical treatment with stearic acid at different temperatures. Using a conical twin-screw extruder and injector, the researchers produced and analyzed the composites both morphologically and mechanically. The principal findings indicated that the inclusion of untreated fibers improved the stiffness and tensile strength of the composites. Nevertheless, adhesion between the fibers and the matrix was compromised, especially with higher fiber concentrations. Chemical treatment at 40 °C significantly improved fiber/matrix interactions, thereby enhancing the reliability and mechanical properties of the composites. This treatment led to substantial increases in tensile and compressive strengths, particularly noticeable in composites containing 10%–15% fiber by weight. These results not only demonstrate the feasibility of using recycled HDPE and sugarcane bagasse fibers in composite materials but also suggest avenues for further exploration. Future research could delve deeper into optimizing chemical treatment processes to achieve even better adhesion and mechanical performance. Moreover, exploring broader applications in industries such as automotive, aerospace, naval, civil engineering, and packaging could unlock new opportunities for these sustainable composites. This study thus paves the way for advancing composite technology towards more environmentally friendly and economically viable solutions.

Published
2024
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8. Demonstration of event position reconstruction based on diffusion in the NEXT-white detector

Author

Haefner, J., Navarro, K. E., Guenette, R., Jones, B. J. P., Tripathi, A., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Auria-Luna, F., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., Barrio-Torregrosa, M. del, Bayo, A., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Brodolin, A., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Cid, L., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Elorza, M., Escada, J., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Hervés Carrete, C., Ifergan, Y., Labarga, L., Larizgoitia, L., Larumbe, A., Lebrun, P., Lopez, F., López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Miller, R. L., Mistry, K., Molina-Canteras, J., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Muñoz Vidal, J., Novella, P., Nuñez, A., Nygren, D. R., Oblak, E., Palacio, J., Palmeiro, B., Para, A., Parmaksiz, I., Pelegrin, J., Pérez Maneiro, M., Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., dos Santos, J. M. F., Shomroni, I., Simón, A., Soleti, S. R., Sorel, M., Soto-Oton, J., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Trettin, A., Usón, A., Veloso, J. F. C. A., Waiton, J., and White, J. T.

Published
2024
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9. Reflectance and fluorescence characteristics of PTFE coated with TPB at visible, UV, and VUV as a function of thickness

Author

Haefner, J., Fahs, A., Ho, J., Stanford, C., Guenette, R., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Auria-Luna, F., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Cossío, F. P., Denisenko, A. A., Dey, E., Díaz, G., Dickel, T., Escada, J., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Ho, P., Ifergan, Y., Jones, B. J. P., Kekic, M., Labarga, L., Larizgoitia, L., Lebrun, P., Gutierrez, D. Lopez, López-March, N., Madigan, R., Mano, R. D. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Marques, A. P., Meziani, Z. E., Miller, R., Mistry, K., Molina-Canteras, J., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Navarro, K., Novella, P., Nuñez, A., Nygren, D. R., Oblak, E., Odriozola-Gimeno, M., Palmeiro, B., Para, A., Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sorel, M., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Vuong, T. T., and Waiton, J.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Physics - Optics
Abstract

Polytetrafluoroethylene (PTFE) is an excellent diffuse reflector widely used in light collection systems for particle physics experiments. In noble element systems, it is often coated with tetraphenyl butadiene (TPB) to allow detection of vacuum ultraviolet scintillation light. In this work this dependence is investigated for PTFE coated with TPB in air for light of wavelengths of 200~nm, 260~nm, and 450~nm. The results show that TPB-coated PTFE has a reflectance of approximately 92\% for thicknesses ranging from 5~mm to 10~mm at 450~nm, with negligible variation as a function of thickness within this range. A cross-check of these results using an argon chamber supports the conclusion that the change in thickness from 5~mm to 10~mm does not affect significantly the light response at 128~nm. Our results indicate that pieces of TPB-coated PTFE thinner than the typical 10~mm can be used in particle physics detectors without compromising the light signal.

Published
2022
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10. Inoculation and co-inoculation of the winter bean and chemical treatment of the seeds

Author

Danielle Bolandim Costa, Marcelo Andreotti, Isabela Malaquias Dalto de Souza, Paulino Taveira de Souza, Matheus Pereira de Brito Mateus, and Ilca Puertas de Freitas e Silva

Subjects
Phaseolus vulgaris, Azospirillum brasilense, Rhizobium tropici, Fungicide, Insecticide., Agriculture (General), S1-972
Abstract

ABSTRACT Given the large differences in the results of inoculation and co-inoculation in the bean crop, an experiment in cultivating winter beans was carried out in 2019 under greenhouse conditions with the aim of evaluating the performance of the beans and a possible increase in plant growth and grain production, using seeds inoculated or co-inoculated with Rhizobium tropici and Azospirillum brasilense, with and without fungicide and/or insecticide, in sandy and clayey soils. A total of 112 pots were used, and 14 treatments were applied in a completely randomised experimental design, with four replications. The Scott-Knott test was used to analyse the results, and showed that whether using untreated seeds or carrying out complete chemical treatment with fungicide and insecticide plus co-inoculation with R. tropici and A. brasilense, winter bean production was reduced in clayey soil, while the joint use of fungicide and insecticide, fungicide and R. tropici, or fungicide, insecticide and R. tropici, favoured shoot development. Inoculating with A. brasilense, without R. tropici and with insecticide, or insecticide and fungicide, favoured greater root growth in clayey soil. In sandy soil, grain production was higher using seeds treated solely with insecticide, solely with R. tropici, or with a combination of both. Production was lower in the joint treatment with fungicide, insecticide and the co-inoculation of bacteria, or when using insecticide together with A. brasilense.

Published
2024
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11. Desenvolvimento e validação de conteúdo de um instrumento de avaliação de mobilidade funcional autorrelatada para pacientes idosos

Author

Eric Alencar Lessa, Carine Freitas e Silva, Lilian Ramine Ramos de Souza Matos, and Francis Trombini-Souza

Subjects
Estudo de Validação, Avaliação Geriátrica, Fraturas do Quadril, Geriatrics, RC952-954.6
Abstract

Resumo Objetivo Desenvolver e validar o conteúdo do Composite Score for Mobility (COSMO) para avaliar a mobilidade funcional autorreferida de pessoas idosas no pós-operatório de fratura de quadril. Métodos Um estudo metodológico foi conduzido envolvendo um painel de especialistas composto por 30 profissionais de saúde com experiência com pacientes idosos hospitalizados após cirurgia de fratura de quadril e um painel de usuários composto por 30 pacientes idosos internados após cirurgia de fratura de quadril. O COSMO foi desenvolvido como um instrumento de medida de resultados relatados pelo paciente (PROM). A validade de conteúdo do COSMO foi avaliada pela técnica Delphi e aplicada aos painéis de juízes, sendo calculado o índice de validade de conteúdo (IVC) para cada questão do instrumento. Resultados A partir das 45 questões respondidas pelos juízes especialistas sobre a relevância e abrangência do COSMO, foi alcançado IVC de 100% em 31 questões, 96,7% em 11 questões, 93,3% em uma questão e 90% em duas questões. Das 85 questões sobre escopo, relevância e compreensão do COSMO respondidas por cada um dos 30 juízes usuários, foi alcançado um IVC de 100% em 83 questões e um IVC de 93,3% em duas questões. Conclusão O COSMO é um instrumento relevante, abrangente, compreensível e válido para avaliar a mobilidade funcional autorreferida em pacientes idosos internados após cirurgia de fratura de quadril.

Published
2024
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13. Reptilia, Squamata, Gymnophthalmidae, Acratosaura mentalis (Amaral 1933): Distribution extension and geographic distribution map.

Author

de-Carvalho, C. B., Caldas, F. L. S., Santana, D. O., Noronha, M. V., Freitas, E. B., Faria, R. G., and Santos, R. A.

Subjects
Biology (General), QH301-705.5
Abstract

This article provides new records to Acratossaura mentalis of two new localities from the state of Sergipe,northeast Brazil. These records extend the geographical distribution of specie for municipalities from Poço Redondo andItabaiana. Possibly, these points are the first records of A. mentalis for the state of Sergipe.

Published
2010

14. Neutral Bremsstrahlung emission in xenon unveiled

Author

Henriques, C. A. O., Amedo, P., Teixeira, J. M. R., Gonzalez-Diaz, D., Azevedo, C. D. R., Para, A., Martin-Albo, J., Hernandez, A. Saa, Gomez-Cadenas, J. J., Nygren, D. R., Monteiro, C. M. B., Adams, C., Alvarez, V., Arazi, L., Arnquist, I. J., Bailey, K., Ballester, F., Benlloch-Rodriguez, J. M., Borges, F. I. G. M., Byrnes, N., Carcel, S., Carrion, J. V., Cebrian, S., Church, E., Conde, C. A. N., Contreras, T., Diaz, G., Diaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., Guenette, R., Gutierrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ifergan, Y., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., Lopez-March, N., Losada, M., Mano, R. D. P., Martinez, A., Martinez-Vara, M., Martinez-Lema, G., McDonald, A. D., Monrabal, F., Mora, F. J., Vidal, J. Munoz, Novella, P., Palmeiro, B., Perez, J., Querol, M., Redwine, A. B., Renner, J., Repond, J., Riordan, S., Ripoll, L., Garcia, Y. Rodriguez, Rodriguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simon, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Uson, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, Astrophysics - Instrumentation and Methods for Astrophysics, Physics - Atomic Physics
Abstract

We present evidence of non-excimer-based secondary scintillation in gaseous xenon, obtained using both the NEXT-White TPC and a dedicated setup. Detailed comparison with first-principle calculations allows us to assign this scintillation mechanism to neutral bremsstrahlung (NBrS), a process that has been postulated to exist in xenon that has been largely overlooked. For photon emission below 1000 nm, the NBrS yield increases from about 10$^{-2}$ photon/e$^{-}$ cm$^{-1}$ bar$^{-1}$ at pressure-reduced electric field values of 50 V cm$^{-1}$ bar$^{-1}$ to above 3$\times$10$^{-1}$ photon/e$^{-}$ cm$^{-1}$ bar$^{-1}$ at 500 V cm$^{-1}$ bar$^{-1}$. Above 1.5 kV cm$^{-1}$ bar$^{-1}$, values that are typically employed for electroluminescence, it is estimated that NBrS is present with an intensity around 1 photon/e$^{-}$ cm$^{-1}$ bar$^{-1}$, which is about two orders of magnitude lower than conventional, excimer-based electroluminescence. Despite being fainter than its excimeric counterpart, our calculations reveal that NBrS causes luminous backgrounds that can interfere, in either gas or liquid phase, with the ability to distinguish and/or to precisely measure low primary-scintillation signals (S1). In particular, we show this to be the case in the "buffer" and "veto" regions, where keeping the electric field below the electroluminescence (EL) threshold will not suffice to extinguish secondary scintillation. The electric field in these regions should be chosen carefully to avoid intolerable levels of NBrS emission. Furthermore, we show that this new source of light emission opens up a viable path towards obtaining S2 signals for discrimination purposes in future single-phase liquid TPCs for neutrino and dark matter physics, with estimated yields up to 20-50 photons/e$^{-}$ cm$^{-1}$., Comment: Published in Physical Review X

Published
2022
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15. Ba$^{2+}$ ion trapping by organic submonolayer: towards an ultra-low background neutrinoless double beta decay detector

Author

Herrero-Gómez, P., Calupitan, J. P., Ilyn, M., Berdonces-Layunta, A., Wang, T., de Oteyza, D. G., Corso, M., González-Moreno, R., Rivilla, I., Aparicio, B., Aranburu, A. I., Freixa, Z., Monrabal, F., Cossío, F. P., Gómez-Cadenas, J. J., Rogero, C., Adams, C., Almazán, H., Alvarez, V., Arazi, L., Arnquist, I. J., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Denisenko, A. A., Díaz, G., Díaz, J., Dickel, T., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Generowicz, J., Goldschmidt, A., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, V., Ho, J., Ifergan, Y., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Larizgoitia, L., Lebrun, P., Gutierrez, D. Lopez, López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Martínez-Vara, M., McDonald, A. D., Meziani, Z. E., Mistry, K., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Navarro, K., Novella, P., Nygren, D. R., Oblak, E., Odriozola-Gimeno, M., Palmeiro, B., Para, A., Pérez, J., Querol, M., Raymond, A., Redwine, A. B., Renner, J., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sorel, M., Stanford, C., Teixeira, J. M. R., Thapa, P., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Vuong, T. T., Webb, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
High Energy Physics - Experiment, Condensed Matter - Materials Science, Physics - Chemical Physics
Abstract

If neutrinos are their own antiparticles, the otherwise-forbidden nuclear reaction known as neutrinoless double beta decay ($\beta\beta 0\nu$) can occur, with a characteristic lifetime which is expected to be very long, making the suppression of backgrounds a daunting task. It has been shown that detecting (``tagging'') the Ba$^{+2}$ dication produced in the double beta decay ${}^{136}\mathrm{Xe} \rightarrow {}^{136}$Ba$^{+2}+ 2 e + (2 \nu)$ in a high pressure gas experiment, could lead to a virtually background free experiment. To identify these \Bapp, chemical sensors are being explored as a key tool by the NEXT collaboration . Although used in many fields, the application of such chemosensors to the field of particle physics is totally novel and requires experimental demonstration of their suitability in the ultra-dry environment of a xenon gas chamber. Here we use a combination of complementary surface science techniques to unambiguously show that Ba$^{+2}$ ions can be trapped (chelated) in vacuum by an organic molecule, the so-called fluorescent bicolour indicator (FBI) (one of the chemosensors developed by NEXT), immobilized on a surface. We unravel the ion capture mechanism once the molecules are immobilised on Au(111) surface and explain the origin of the emission fluorescence shift associated to the trapping of different ions. Moreover, we prove that chelation also takes place on a technologically relevant substrate, as such, demonstrating the feasibility of using FBI indicators as building blocks of a Ba$^{+2}$ detector.

Published
2022
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16. Measurement of the ${}^{136}$Xe two-neutrino double beta decay half-life via direct background subtraction in NEXT

Author

NEXT Collaboration, Novella, P., Sorel, M., Usón, A., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Cossío, F. P., Denisenko, A. A., Díaz, G., Díaz, J., Dickel, T., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero-Gómez, P., Herrero, V., Ho, J., Ifergan, Y., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Larizgoitia, L., Lebrun, P., Gutierrez, D. Lopez, López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Martínez-Vara, M., McDonald, A. D., Meziani, Z. E., Mistry, K., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Navarro, K., Nygren, D. R., Oblak, E., Odriozola-Gimeno, M., Palmeiro, B., Para, A., Pérez, J., Querol, M., Raymond, A., Redwine, A. B., Renner, J., Ripoll, L., Rivilla, I., García, Y. Rodríguez, Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Stanford, C., Teixeira, J. M. R., Thapa, P., Toledo, J. F., Torrent, J., Veloso, J. F. C. A., Vuong, T. T., Webb, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, Physics - Instrumentation and Detectors
Abstract

We report a measurement of the half-life of the ${}^{136}$Xe two-neutrino double beta decay performed with a novel direct background subtraction technique. The analysis relies on the data collected with the NEXT-White detector operated with ${}^{136}$Xe-enriched and ${}^{136}$Xe-depleted xenon, as well as on the topology of double-electron tracks. With a fiducial mass of only 3.5 kg of Xe, a half-life of $2.34^{+0.80}_{-0.46}\textrm{(stat)}^{+0.30}_{-0.17}\textrm{(sys)}\times10^{21}~\textrm{yr}$ is derived from the background-subtracted energy spectrum. The presented technique demonstrates the feasibility of unique background-model-independent neutrinoless double beta decay searches., Comment: 9 pages, 7 figures, and 1 appendix

Published
2021
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17. The Dynamics of Ions on Phased Radio-frequency Carpets in High Pressure Gases and Application for Barium Tagging in Xenon Gas Time Projection Chambers

Author

NEXT Collaboration, Jones, B. J. P., Raymond, A., Woodruff, K., Byrnes, N., Denisenko, A. A., Foss, F. W., Navarro, K., Nygren, D. R., Vuong, T. T., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Cossío, F. P., Díaz, G., Díaz, J., Dickel, T., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Freixa, Z, Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Hernando~Morata, J. A., Herrero-Gómez, P., Herrero, V., Ho, J., Ifergan, Y., Kekic, M., Labarga, L., Laing, A., Lebrun, P., Gutierrez, D. Lopez, López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Martínez-Vara, M., McDonald, A. D., Meziani, Z. E., Mistry, K., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Oblak, E., Odriozola-Gimeno, M., Palmeiro, B., Para, A., Pérez, J., Querol, M., Redwine, A. B., Renner, J., Ripoll, L., Rivilla, I., García, Y. Rodríguez, Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sorel, M., Stanford, C., Teixeira, J. M. R., Thapa, P., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

Radio-frequency (RF) carpets with ultra-fine pitches are examined for ion transport in gases at atmospheric pressures and above. We develop new analytic and computational methods for modeling RF ion transport at densities where dynamics are strongly influenced by buffer gas collisions. An analytic description of levitating and sweeping forces from phased arrays is obtained, then thermodynamic and kinetic principles are used to calculate ion loss rates in the presence of collisions. This methodology is validated against detailed microscopic SIMION simulations. We then explore a parameter space of special interest for neutrinoless double beta decay experiments: transport of barium ions in xenon at pressures from 1 to 10 bar. Our computations account for molecular ion formation and pressure dependent mobility as well as finite temperature effects. We discuss the challenges associated with achieving suitable operating conditions, which lie beyond the capabilities of existing devices, using presently available or near-future manufacturing techniques., Comment: 26 pages, 16 figures v2: author list update and pre-journal submission adjustments

Published
2021

19. Trypanosoma cruzi killing and immune response boosting by novel phenoxyhydrazine-thiazole against Chagas disease

Author

Cristovão-Silva, Ana Catarina, Brelaz-de-Castro, Maria Carolina Accioly, Dionisio da Silva, Elis, Leite, Ana Cristina Lima, Santiago, Lizandra Beatriz Amorim Alves, Conceição, Juliana Maria da, da Silva Tiburcio, Robert, de Santana, Davi Pereira, Bedor, Danilo Cesar Galindo, de Carvalho, Breno Ítalo Valença, Ferreira, Luiz Felipe Gomes Rebello, de Freitas e Silva, Rafael, Alves Pereira, Valéria Rêgo, and Hernandes, Marcelo Zaldini

Published
2024
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20. Cultural adaptation and validity evidence of the Student Nurse Stressor-15 (SNS-15) Scale for Brazil

Author

Agostinho Antônio Cruz Araújo, Simone de Godoy, Natália Maria Freitas e Silva Maia, Maria Eduarda Bonissoni Trevelin, Kelly Graziani Giacchero Vedana, Carmem Beatriz Neufeld, Neyson Pinheiro Freire, Carla Aparecida Arena Ventura, Patricia McAleer, and Isabel Amélia Costa Mendes

Subjects
Education, Nursing, Stress, Psychological, Students, Nursing, Validation Study, Psychometrics, RT1-120
Abstract

ABSTRACT Objectives: to carry out the cultural adaptation and evaluation of validity evidence of the Student Nurse Stressor-15 (SNS-15) Scale for use in Brazil. Methods: psychometric study, conducted from the stages of translation, synthesis, back-translation, review by a committee of seven experts, pre-test and evaluation of measurement properties with 32 and 238 nursing students, respectively. Descriptive statistics, Exploratory Factor Analysis (EFA), and Confirmatory Factor Analysis (CFA) were performed. The reliability of the instrument was estimated using McDonald’s Omega (ω). Results: EFA subsidized the distribution of the fifteen SNS-15 items into four factors. Using AFC, satisfactory fit indices were achieved (Comparative Fit Index = 0.94; Tucker-Lewis Index = 0.93; Root Mean Square Error of Approximation = 0.06; Standardized Root Mean Square Residual = 0.16) and ω = 0.86. Conclusions: the Brazilian version of the SNS-15 presents evidence that confirms its validity and reliability.

Published
2024
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21. AVANÇOS RECENTES NA COMPREENSÃO E NO TRATAMENTO DA EPILEPSIA: UMA REVISÃO DA LITERATURA

Author

RAYSA SALES RODRIGUES, SAMIA, primary, MARRY SILVA DE MORAIS, LANNA, additional, FREITAS E SILVA FILHO, MURILO, additional, FORTES DE SOUSA, WANDERSON, additional, GUSTAVO DA SILVA MELO, IGOR, additional, OLIVEIRA DE SOUSA LIMA, BRUNO, additional, CAMILA LINS SIQUEIRA ALMEIDA, OHANA, additional, KAROLYNNE SOUSA COIMBRA, FERNANDA, additional, DIAS MOTA, ISAAC, additional, AUGUSTO OLIVEIRA DO CARMO SILVA, FÁBIO, additional, DA SILVA BRAGA, NICOLE, additional, and LUCAS LOPES E SILVA, GUSTAVO, additional

Published
2023
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22. Boosting background suppression in the NEXT experiment through Richardson-Lucy deconvolution

Author

Simón, A., Ifergan, Y., Redwine, A. B., Weiss-Babai, R., Arazi, L., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Cossío, F. P., Denisenko, A. A., Díaz, G., Díaz, J., Escada, J., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., González-Díaz, D., Gosh, S., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ho, J., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Vara, M., Martínez-Lema, G., McDonald, A. D., Meziani, Z. -E., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Newhouse, C., Novella, P., Nygren, D. R., Oblak, E., Odriozola-Gimeno, M., Palmeiro, B., Para, A., Pérez, J., Querol, M., Renner, J., Ripoll, L., Rivilla, I., García, Y. Rodríguez, Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Sorel, M., Stanford, C., Teixeira, J. M. R., Thapa, P., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Vuong, T. T., Webb, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

Next-generation neutrinoless double beta decay experiments aim for half-life sensitivities of ~$10^{27}$ yr, requiring suppressing backgrounds to <1 count/tonne/yr. For this, any extra background rejection handle, beyond excellent energy resolution and the use of extremely radiopure materials, is of utmost importance. The NEXT experiment exploits differences in the spatial ionization patterns of double beta decay and single-electron events to discriminate signal from background. While the former display two Bragg peak dense ionization regions at the opposite ends of the track, the latter typically have only one such feature. Thus, comparing the energies at the track extremes provides an additional rejection tool. The unique combination of the topology-based background discrimination and excellent energy resolution (1% FWHM at the Q-value of the decay) is the distinguishing feature of NEXT. Previous studies demonstrated a topological background rejection factor of ~5 when reconstructing electron-positron pairs in the $^{208}$Tl 1.6 MeV double escape peak (with Compton events as background), recorded in the NEXT-White demonstrator at the Laboratorio Subterr\'aneo de Canfranc, with 72% signal efficiency. This was recently improved through the use of a deep convolutional neural network to yield a background rejection factor of ~10 with 65% signal efficiency. Here, we present a new reconstruction method, based on the Richardson-Lucy deconvolution algorithm, which allows reversing the blurring induced by electron diffusion and electroluminescence light production in the NEXT TPC. The new method yields highly refined 3D images of reconstructed events, and, as a result, significantly improves the topological background discrimination. When applied to real-data 1.6 MeV $e^-e^+$ pairs, it leads to a background rejection factor of 27 at 57% signal efficiency., Comment: Submitted to JHEP

Published
2021
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23. Demonstration of background rejection using deep convolutional neural networks in the NEXT experiment

Author

NEXT Collaboration, Kekic, M., Adams, C., Woodruff, K., Renner, J., Church, E., Del Tutto, M., Morata, J. A. Hernando, Gomez-Cadenas, J. J., Alvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodriguez, J. M., Borges, F. I. G. M., Byrnes, N., Carcel, S., Carrion, J. V., Cebrian, S., Conde, C. A. N., Contreras, T., Diaz, G., Diaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., Gonzalez-Diaz, D., Guenette, R., Gutierrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Herrero, P., Herrero, V., Ifergan, Y., Jones, B. J. P., Labarga, L., Laing, A., Lebrun, P., Lopez-March, N., Losada, M., Mano, R. D. P., Martin-Albo, J., Martinez, A., Martinez-Lema, G., Martinez-Vara, M., McDonald, A. D., Meziani, Z. E., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Perez, J., Querol, M., Redwine, A. B., Ripoll, L., Garcia, Y. Rodriguez, Rodriguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simon, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Uson, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

Convolutional neural networks (CNNs) are widely used state-of-the-art computer vision tools that are becoming increasingly popular in high energy physics. In this paper, we attempt to understand the potential of CNNs for event classification in the NEXT experiment, which will search for neutrinoless double-beta decay in $^{136}$Xe. To do so, we demonstrate the usage of CNNs for the identification of electron-positron pair production events, which exhibit a topology similar to that of a neutrinoless double-beta decay event. These events were produced in the NEXT-White high-pressure xenon TPC using 2.6-MeV gamma rays from a $^{228}$Th calibration source. We train a network on Monte Carlo-simulated events and show that, by applying on-the-fly data augmentation, the network can be made robust against differences between simulation and data. The use of CNNs offer significant improvement in signal efficiency/background rejection when compared to previous non-CNN-based analyses., Comment: 19 pages, 10 figures; version matches published JHEP version

Published
2020
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24. Dependence of polytetrafluoroethylene reflectance on thickness at visible and ultraviolet wavelengths in air

Author

Ghosh, S., Haefner, J., Martín-Albo, J., Guenette, R., Li, X., Villalpando, A. A. Loya, Burch, C., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Díaz, G., Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Gutiérrez, R. M., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ifergan, Y., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martínez, A., Martínez-Vara, M., Martínez-Lema, G., McDonald, A. D., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Querol, M., Redwine, A., Renner, J., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors
Abstract

Polytetrafluoroethylene (PTFE) is an excellent diffuse reflector widely used in light collection systems for particle physics experiments. However, the reflectance of PTFE is a function of its thickness. In this work, we investigate this dependence in air for light of wavelengths 260 nm and 450 nm using two complementary methods. We find that PTFE reflectance for thicknesses from 5 mm to 10 mm ranges from 92.5% to 94.5% at 450 nm, and from 90.0% to 92.0% at 260 nm. We also see that the reflectance of PTFE of a given thickness can vary by as much as 2.7% within the same piece of material. Finally, we show that placing a specular reflector behind the PTFE can recover the loss of reflectance in the visible without introducing a specular component in the reflectance., Comment: 17 pages, 10 figures

Published
2020
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25. Sensitivity of the NEXT experiment to Xe-124 double electron capture

Author

Martínez-Lema, G., Martínez-Vara, M., Sorel, M., Adams, C., Alvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Díaz, G., Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ifergan, Y., Johnston, S., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., McDonald, A. D., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Querol, M., Redwine, A. B., Renner, J., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Stiegler, T., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
High Energy Physics - Experiment, Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract

Double electron capture by proton-rich nuclei is a second-order nuclear process analogous to double beta decay. Despite their similarities, the decay signature is quite different, potentially providing a new channel to measure the hypothesized neutrinoless mode of these decays. The Standard-Model-allowed two-neutrino double electron capture ($2\nu ECEC$) has been predicted for a number of isotopes, but only observed in $^{78}$Kr, $^{130}$Ba and, recently, $^{124}$Xe. The sensitivity to this decay establishes a benchmark for the ultimate experimental goal, namely the potential to discover also the lepton-number-violating neutrinoless version of this process, $0\nu ECEC$. Here we report on the current sensitivity of the NEXT-White detector to $^{124}$Xe $2\nu ECEC$ and on the extrapolation to NEXT-100. Using simulated data for the $2\nu ECEC$ signal and real data from NEXT-White operated with $^{124}$Xe-depleted gas as background, we define an optimal event selection that maximizes the NEXT-White sensitivity. We estimate that, for NEXT-100 operated with xenon gas isotopically enriched with 1 kg of $^{124}$Xe and for a 5-year run, a sensitivity to the $2\nu ECEC$ half-life of $6 \times 10^{22}$ y (at 90% confidence level) or better can be reached., Comment: 23 pages, 13 figures

Published
2020
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26. Sensitivity of a tonne-scale NEXT detector for neutrinoless double beta decay searches

Author

NEXT Collaboration, Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Denisenko, A. A., Díaz, G., Díaz, J., Escada, J., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., González-Díaz, D., Gosh, S., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ho, J., Ifergan, Y., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Vara, M., Martínez-Lema, G., McDonald, A. D., Meziani, Z. E., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Newhouse, C., Novella, P., Nygren, D. R., Oblak, E., Palmeiro, B., Para, A., Pérez, J., Querol, M., Redwine, A., Renner, J., Ripoll, L., Rivilla, I., García, Y. Rodríguez, Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sorel, M., Stanford, C., Teixeira, J. M. R., Thapa, P., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Vuong, T. T., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

The Neutrino Experiment with a Xenon TPC (NEXT) searches for the neutrinoless double-beta decay of Xe-136 using high-pressure xenon gas TPCs with electroluminescent amplification. A scaled-up version of this technology with about 1 tonne of enriched xenon could reach in less than 5 years of operation a sensitivity to the half-life of neutrinoless double-beta decay decay better than 1E27 years, improving the current limits by at least one order of magnitude. This prediction is based on a well-understood background model dominated by radiogenic sources. The detector concept presented here represents a first step on a compelling path towards sensitivity to the parameter space defined by the inverted ordering of neutrino masses, and beyond., Comment: 22 pages, 11 figures

Published
2020

27. Mitigation of Backgrounds from Cosmogenic $^{137}$Xe in Xenon Gas Experiments using $^{3}$He Neutron Capture

Author

Rogers, L., Jones, B. J. P., Laing, A., Pingulkar, S., Woodruff, K., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Díaz, G., Díaz, J., Diesburg, M., Dingler, R., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ifergan, Y., Johnston, S., Kekic, M., Labarga, L., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., McDonald, A. D., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Querol, M., Redwine, A. B., Renner, J., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

\Xe{136} is used as the target medium for many experiments searching for \bbnonu. Despite underground operation, cosmic muons that reach the laboratory can produce spallation neutrons causing activation of detector materials. A potential background that is difficult to veto using muon tagging comes in the form of \Xe{137} created by the capture of neutrons on \Xe{136}. This isotope decays via beta decay with a half-life of 3.8 minutes and a \Qb\ of $\sim$4.16 MeV. This work proposes and explores the concept of adding a small percentage of \He{3} to xenon as a means to capture thermal neutrons and reduce the number of activations in the detector volume. When using this technique we find the contamination from \Xe{137} activation can be reduced to negligible levels in tonne and multi-tonne scale high pressure gas xenon neutrinoless double beta decay experiments running at any depth in an underground laboratory.

Published
2020
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28. Demonstration of neutrinoless double beta decay searches in gaseous xenon with NEXT

Author

Novella, P., Sorel, M., Usón, A., Adams, C., Almazán, H., Álvarez, V., Aparicio, B., Aranburu, A. I., Arazi, L., Arnquist, I. J., Auria-Luna, F., Ayet, S., Azevedo, C. D. R., Bailey, K., Ballester, F., del Barrio-Torregrosa, M., Bayo, A., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Bounasser, S., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Cid, L., Conde, C. A. N., Contreras, T., Cossío, F. P., Dey, E., Díaz, G., Dickel, T., Elorza, M., Escada, J., Esteve, R., Fahs, A., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss, F. W., Freitas, E. D. C., Freixa, Z., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., González, R., Grocott, J., Guenette, R., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Hernando Morata, J. A., Herrero-Gómez, P., Herrero, V., Hervés Carrete, C., Ho, J., Ho, P., Ifergan, Y., Jones, B. J. P., Labarga, L., Larizgoitia, L., Larumbe, A., Lebrun, P., Lopez, F., Lopez Gutierrez, D., López-March, N., Madigan, R., Mano, R. D. P., Marques, A. P., Martín-Albo, J., Martínez-Lema, G., Martínez-Vara, M., Meziani, Z. E., Miller, R. L., Mistry, K., Molina-Canteras, J., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Muñoz Vidal, J., Navarro, K., Nuñez, A., Nygren, D. R., Oblak, E., Odriozola-Gimeno, M., Palacio, J., Palmeiro, B., Para, A., Parmaksiz, I., Pelegrin, J., Pérez Maneiro, M., Querol, M., Redwine, A. B., Renner, J., Rivilla, I., Rodríguez, J., Rogero, C., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., dos Santos, J. M. F., Simón, A., Soleti, S. R., Stanford, C., Teixeira, J. M. R., Toledo, J. F., Torrent, J., Veloso, J. F. C. A., Vuong, T. T., Waiton, J., and White, J. T.

Published
2023
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29. 1,3-Thiazole derivatives as privileged structures for anti-Trypanosoma cruzi activity: Rational design, synthesis, in silico and in vitro studies

Author

Cox Holanda de Barros Dias, Mabilly, Souza Barbalho, Mayara, Bezerra de Oliveira Filho, Gevanio, Veríssimo de Oliveira Cardoso, Marcos, Lima Leite, Ana Cristina, da Silva Santos, Aline Caroline, Cristovão Silva, Ana Catarina, Accioly Brelaz de Castro, Maria Carolina, Maria Nascimento Moura, Danielle, Gomes Rebello Ferreira, Luiz Felipe, Zaldini Hernandes, Marcelo, de Freitas e Silva, Rafael, and Rêgo Alves Pereira, Valéria

Published
2023
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32. Radio Frequency and DC High Voltage Breakdown of High Pressure Helium, Argon, and Xenon

Author

Woodruff, K., Baeza-Rubio, J., Huerta, D., Jones, B. J. P., McDonald, A. D., Norman, L., Nygren, D. R., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N. K., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Denisenko, A. A., Díaz, G., Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Foss Jr., F. W., Freitas, E. D. C., Generowicz, J., Goldschmidt, A., González-Díaz, D., Gómez-Cadenas, J. J., Ghosh, S., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Johnston, S., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Palmeiro, B., Para, A., Pérez, J., Querol, M., Renner, J., Repond, J., Riordan, S., Ripoll, L., Garcia, Y. Rodriguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Thapa, P., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

Motivated by the possibility of guiding daughter ions from double beta decay events to single-ion sensors for barium tagging, the NEXT collaboration is developing a program of R&D to test radio frequency (RF) carpets for ion transport in high pressure xenon gas. This would require carpet functionality in regimes at higher pressures than have been previously reported, implying correspondingly larger electrode voltages than in existing systems. This mode of operation appears plausible for contemporary RF-carpet geometries due to the higher predicted breakdown strength of high pressure xenon relative to low pressure helium, the working medium in most existing RF carpet devices. In this paper we present the first measurements of the high voltage dielectric strength of xenon gas at high pressure and at the relevant RF frequencies for ion transport (in the 10 MHz range), as well as new DC and RF measurements of the dielectric strengths of high pressure argon and helium gases at small gap sizes. We find breakdown voltages that are compatible with stable RF carpet operation given the gas, pressure, voltage, materials and geometry of interest.

Published
2019
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33. Low-diffusion Xe-He gas mixtures for rare-event detection: Electroluminescence Yield

Author

Fernandes, A. F. M., Henriques, C. A. O., Mano, R. D. P., González-Díaz, D., Azevedo, C. D. R., Silva, P. A. O. C., Gómez-Cadenas, J. J., Freitas, E. D. C., Fernandes, L. M. P., Monteiro, C. M. B., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carríon, J. V., Cebrían, S., Church, E., Conde, C. A. N., Contreras, T., Díaz, J., Díaz, G., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Ferrario, P., Ferreira, A. L., Generowicz, J., Ghosh, S., Goldschmidt, A., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ifergan, Y., Johnston, S., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Martín-Albo, J., Martínez, A., Martínez-Lema, G., McDonald, A. D., Monrabal, F., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Psihas, F., Querol, M., Renner, J., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, Physics - Applied Physics
Abstract

High pressure xenon Time Projection Chambers (TPC) based on secondary scintillation (electroluminescence) signal amplification are being proposed for rare event detection such as directional dark matter, double electron capture and double beta decay detection. The discrimination of the rare event through the topological signature of primary ionisation trails is a major asset for this type of TPC when compared to single liquid or double-phase TPCs, limited mainly by the high electron diffusion in pure xenon. Helium admixtures with xenon can be an attractive solution to reduce the electron diffusion significantly, improving the discrimination efficiency of these optical TPCs. We have measured the electroluminescence (EL) yield of Xe-He mixtures, in the range of 0 to 30% He and demonstrated the small impact on the EL yield of the addition of helium to pure xenon. For a typical reduced electric field of 2.5 kV/cm/bar in the scintillation region, the EL yield is lowered by ~ 2%, 3%, 6% and 10% for 10%, 15%, 20% and 30% of helium concentration, respectively. This decrease is less than what has been obtained from the most recent simulation framework in the literature. The impact of the addition of helium on EL statistical fluctuations is negligible, within the experimental uncertainties. The present results are an important benchmark for the simulation tools to be applied to future optical TPCs based on Xe-He mixtures.

Published
2019

34. Radiogenic backgrounds in the NEXT double beta decay experiment

Author

NEXT Collaboration, Novella, P., Palmeiro, B., Sorel, M., Usón, A., Ferrario, P., Gómez-Cadenas, J. J., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., López, G. Díaz, Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Ifergan, Y., Johnston, S., Jones, B. J. P., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., McDonald, A. D., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Nygren, D. R., Para, A., Pérez, J., Psihas, F., Querol, M., Renner, J., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Stiegler, T., Toledo, J. F., Torrent, J., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

Natural radioactivity represents one of the main backgrounds in the search for neutrinoless double beta decay. Within the NEXT physics program, the radioactivity-induced backgrounds are measured with the NEXT-White detector. Data from 37.9 days of low-background operations at the Laboratorio Subterr\'aneo de Canfranc with xenon depleted in $^{136}$Xe are analyzed to derive a total background rate of (0.84$\pm$0.02) mHz above 1000 keV. The comparison of data samples with and without the use of the radon abatement system demonstrates that the contribution of airborne-Rn is negligible. A radiogenic background model is built upon the extensive radiopurity screening campaign conducted by the NEXT Collaboration. A spectral fit to this model yields the specific contributions of $^{60}$Co, $^{40}$K, $^{214}$Bi and $^{208}$Tl to the total background rate, as well as their location in the detector volumes. The results are used to evaluate the impact of the radiogenic backgrounds in the double beta decay analyses, after the application of topological cuts that reduce the total rate to (0.25$\pm$0.01) mHz. Based on the best-fit background model, the NEXT-White median sensitivity to the two-neutrino double beta decay is found to be 3.5$\sigma$ after 1 year of data taking. The background measurement in a Q$_{\beta\beta}\pm$100 keV energy window validates the best-fit background model also for the neutrinoless double beta decay search with NEXT-100. Only one event is found, while the model expectation is (0.75$\pm$0.12) events.

Published
2019
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35. Energy calibration of the NEXT-White detector with 1% resolution near Q$_{\beta\beta}$ of $^{136}$Xe

Author

Renner, J., López, G. Díaz, Ferrario, P., Morata, J. A. Hernando, Kekic, M., Martínez-Lema, G., Monrabal, F., Gómez-Cadenas, J. J., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Herrero, P., Herrero, V., Ifergan, Y., Johnston, S., Jones, B. J. P., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., McDonald, A. D., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Psihas, F., Querol, M., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors
Abstract

Excellent energy resolution is one of the primary advantages of electroluminescent high pressure xenon TPCs, and searches for rare physics events such as neutrinoless double-beta decay ($\beta\beta0\nu$) require precise energy measurements. Using the NEXT-White detector, developed by the NEXT (Neutrino Experiment with a Xenon TPC) collaboration, we show for the first time that an energy resolution of 1% FWHM can be achieved at 2.6 MeV, establishing the present technology as the one with the best energy resolution of all xenon detectors for $\beta\beta0\nu$ searches., Comment: 13 pages, 7 figures; accepted to JHEP

Published
2019
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36. Demonstration of the event identification capabilities of the NEXT-White detector

Author

NEXT Collaboration, Ferrario, P., Benlloch-Rodríguez, J. M., López, G. Díaz, Morata, J. A. Hernando, Kekic, M., Renner, J., Usón, A., Gómez-Cadenas, J. J., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Borges, F. I. G. M., Byrnes, N., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Contreras, T., Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Ghosh, S., Goldschmidt, A., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Herrero, P., Herrero, V., Ifergan, Y., Johnston, S., Jones, B. J. P., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., McDonald, A. D., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Vidal, J. Muñoz, Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Psihas, F., Querol, M., Repond, J., Riordan, S., Ripoll, L., García, Y. Rodríguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Veloso, J. F. C. A., Webb, R., Weiss-Babai, R., White, J. T., Woodruff, K., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, High Energy Physics - Experiment
Abstract

In experiments searching for neutrinoless double-beta decay, the possibility of identifying the two emitted electrons is a powerful tool in rejecting background events and therefore improving the overall sensitivity of the experiment. In this paper we present the first measurement of the efficiency of a cut based on the different event signatures of double and single electron tracks, using the data of the NEXT-White detector, the first detector of the NEXT experiment operating underground. Using a \TO\ calibration source to produce signal-like and background-like events with energies near 1.6 MeV, a signal efficiency of $71.6 \pm 1.5_{\textrm{ stat}} \pm 0.3_{\textrm{ sys}} \%$ for a background acceptance of $20.6 \pm 0.4_{\textrm{ stat}} \pm 0.3_{\textrm{ sys}} \%$ is found, in good agreement with Monte Carlo simulations. An extrapolation to the energy region of the neutrinoless double beta decay by means of Monte Carlo simulations is also carried out, and the results obtained show an improvement in background rejection over those obtained at lower energies., Comment: Accepted by JHEP

Published
2019
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38. Electron Drift and Longitudinal Diffusion in High Pressure Xenon-Helium Gas Mixtures

Author

McDonald, A. D., Woodruff, K., Atoum, B. Al, González-Díaz, D., Jones, B. J. P., Adams, C., Álvarez, V., Arazi, L., Arnquist, I. J., Azevedo, C. D. R, Bailey, K., Ballester, F., Benlloch-Rodríguez, J. M., Borges, F. I. G. M., Cárcel, S., Carrión, J. V., Cebrián, S., Church, E., Conde, C. A. N., Díaz, G., Díaz, J., Diesburg, M., Escada, J., Esteve, R., Felkai, R., Fernandes, A. F. M., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Generowicz, J., Goldschmidt, A., Gómez-Cadenas, J. J., Guenette, R., Gutiérrez, R. M., Haefner, J., Hafidi, K., Hauptman, J., Henriques, C. A. O., Morata, J. A. Hernando, Herrero, P., Herrero, V., Johnston, S., Kekic, M., Labarga, L., Laing, A., Lebrun, P., López-March, N., Losada, M., Mano, R. D. P., Martín-Albo, J., Martínez, A., Martínez-Lema, G., Monrabal, F., Monteiro, C. M. B., Mora, F. J., MuñozVidal, J., Novella, P., Nygren, D. R., Palmeiro, B., Para, A., Pérez, J., Querol, M., Renner, J., Repond, J., Riordan, S., Ripoll, L., Garcia, Y. Rodriguez, Rodríguez, J., Rogers, L., Romeo, B., Romo-Luque, C., Santos, F. P., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Usón, A., Veloso, J. F. C. A., Webb, R., Weiss-Babai, White, J. T., and Yahlali, N.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

We report new measurements of the drift velocity and longitudinal diffusion coefficients of electrons in pure xenon gas and in xenon-helium gas mixtures at 1-9 bar and electric field strengths of 50-300 V/cm. In pure xenon we find excellent agreement with world data at all $E/P$, for both drift velocity and diffusion coefficients. However, a larger value of the longitudinal diffusion coefficient than theoretical predictions is found at low $E/P$ in pure xenon, below the range of reduced fields usually probed by TPC experiments. A similar effect is observed in xenon-helium gas mixtures at somewhat larger $E/P$. Drift velocities in xenon-helium mixtures are found to be theoretically well predicted. Although longitudinal diffusion in xenon-helium mixtures is found to be larger than anticipated, extrapolation based on the measured longitudinal diffusion coefficients suggest that the use of helium additives to reduce transverse diffusion in xenon gas remains a promising prospect.

Published
2019
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39. Study of the loss of Xenon Scintillation in Xenon-Trimethylamine Mixtures

Author

Trindade, A. M. F., Escada, J., Cortez, A. F. V., Borges, F. I. G. M., Santos, F. P., Adams, C., Álvarez, V., Arazi, L., Azevedo, C. D. R., Ballester, F., Benlloch-Rodríguez, J. M., Botas, A., Cárcel, S., Carríon, J. V., Cebrián, S., Conde, C. A. N., Díaz, J., Diesburg, M., Esteve, R., Felkai, R., Fernandes, L. M. P., Ferrario, P., Ferreira, A. L., Freitas, E. D. C., Goldschmidt, A., Gómez-Cadenas, J. J., González-Díaz, D., Guenette, R., Gutiérrez, R. M., Hafidi, K., Hauptman, J., Henriques, C. A. O., Hernandez, A. I., Morata, J. A. Hernando, Herrero, V., Johnston, S., Jones, B. J. P., Labarga, L., Laing, A., Lebrun, P., Liubarsky, I., López-March, N., Losada, M., Martín-Albo, J., Martínez-Lema, G., Martínez, A., McDonald, A. D., Monrabal, F., Monteiro, C. M. B., Mora, F. J., Moutinho, L. M., Vidal, J. Muñoz, Musti, M., Nebot-Guinot, M., Novella, P., Nygrenq, D. R., Palmeiro, B., Para, A., Pérez, J., Querol, M., Renner, J., Repond, J., Riordan, S., Ripoll, L., Rodríguez, J., Rogers, L., Santos, J. M. F. dos, Simón, A., Sofka, C., Sorel, M., Stiegler, T., Toledo, J. F., Torrent, J., Tsamalaidze, Z., Veloso, J. F. C. A., Webb, R., White, J. T., and Yahlalid, N.

Subjects
Physics - Instrumentation and Detectors
Abstract

This work investigates the capability of TMA ((CH3)3N) molecules to shift the wavelength of Xe VUV emission (160-188 nm) to a longer, more manageable, wavelength (260-350 nm). Light emitted from a Xe lamp was passed through a gas chamber filled with Xe-TMA mixtures at 800 Torr and detected with a photomultiplier tube. Using bandpass filters in the proper transmission ranges, no reemitted light was observed experimentally. Considering the detection limit of the experimental system, if reemission by TMA molecules occurs, it is below 0.3% of the scintillation absorbed in the 160-188 nm range. An absorption coefficient value for xenon VUV light by TMA of 0.43+/-0.03 cm-1.Torr-1 was also obtained. These results can be especially important for experiments considering TMA as a molecular additive to Xe in large volume optical time projection chambers., Comment: 13 pages, 9 figures, 2 tables

Published
2018
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40. Student retention policies in higher education: reflections from a literature review for the Brazilian context/Politicas de permanencia estudantil na educacao superior: reflexoes de uma revisao da literatura para o contexto brasileiro/Politicas de retencion de estudiantes en educacion superior: reflexiones a partir de una revision de la literatura para el contexto brasileno

Author

Silva, Polyana Tenorio de Freitas e and Sampaio, Luciano Menezes Bezerra

Published
2022
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41. A Review About Equipment for Mechanical Ventilation in Intensive Care to Combat COVID-19 and the Role of Clinical Engineers

Author

Freitas, E. V. S., Arteaga, M. A. P., Cardoso, P. A., Tótola, D. L., Coelho, Y. L., Vivas, G. C., Delisle-Rodríguez, D., Santos, F. A., Bastos-Filho, T. F., Magjarevic, Ratko, Series Editor, Ładyżyński, Piotr, Associate Editor, Ibrahim, Fatimah, Associate Editor, Lackovic, Igor, Associate Editor, Rock, Emilio Sacristan, Associate Editor, Bastos-Filho, Teodiano Freire, editor, de Oliveira Caldeira, Eliete Maria, editor, and Frizera-Neto, Anselmo, editor

Published
2022
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42. Proposal of a New Socially Assistive Robot with Embedded Serious Games for Therapy with Children with Autistic Spectrum Disorder and down Syndrome

Author

Panceri, João. Antonio Campos, Freitas, E. V. S., Schreider, S. L., Caldeira, E., Bastos-Filho, T. F., Magjarevic, Ratko, Series Editor, Ładyżyński, Piotr, Associate Editor, Ibrahim, Fatimah, Associate Editor, Lackovic, Igor, Associate Editor, Rock, Emilio Sacristan, Associate Editor, Bastos-Filho, Teodiano Freire, editor, de Oliveira Caldeira, Eliete Maria, editor, and Frizera-Neto, Anselmo, editor

Published
2022
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43. A Review About the Main Technologies to Fight COVID-19

Author

Cardoso, P. A., Tótola, D. L., Freitas, E. V. S., Arteaga, M. A. P., Delisle-Rodríguez, D., Santos, F. A., Bastos-Filho, T. F., Magjarevic, Ratko, Series Editor, Ładyżyński, Piotr, Associate Editor, Ibrahim, Fatimah, Associate Editor, Lackovic, Igor, Associate Editor, Rock, Emilio Sacristan, Associate Editor, Bastos-Filho, Teodiano Freire, editor, de Oliveira Caldeira, Eliete Maria, editor, and Frizera-Neto, Anselmo, editor

Published
2022
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45. ANALYSIS OF THE FREQUENCY OF SINGLE NUCLEOTIDE POLYMORPHISMS IN THE INNATE IMMUNE RESPONSE GENES NRAMP1 AND BMAP-28 RELATED TO RESISTANCE OR SUSCEPTIBILITY TO BOVINE MASTITIS /ANÁLISE DA FREQUÊNCIA DOS POLIMORFISMOS DE NUCLEOTÍDEO ÚNICO NOS GENES DA RESPOSTA IMUNE INATA N RAMPI E BMAP-28 RELACIONADOS À RESISTÊNCIA OU SUSCEPTIBILIDADE À MASTITE BOVINA /ANÁLISIS DE LA FRECUENCIA DE POLIMORFISMOS DE NUCLEÃ'TIDO ÚNICO EN LOS GENES DE LA RESPUESTA INMUNE INNATA NRAMP1 Y BMAP-28 RELACIONADOS CON LA RESISTENCIA O SUSCEPTIBILIDAD A LA MASTITIS BOVINA

Author

da Silva Araújo, Tiago, de Souza, Emerson Pequeno, de Freitas e Silva, Rafael, Falcão, Rosângela Estêvão Alves, and da Mota Silveira-Filho, Vladimir

Published
2023
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46. Decolonial epistemologies for energy planning in Brazil

Author

De Freitas E. Silva, Angelica

Subjects
346.04, Energy planning, decolonial epistemologies, coloniality, colonial difference, ethics of exhaustion, ethics of abundance
Abstract

This thesis opens up theoretical pathways for decolonial epistemologies for energy planning in Brazil. The critical analysis is verticalized from the 2015-2024 Brazilian Decennial Energy Expansion Plan (DEEP) to better highlight the epistemological problems in energy planning. Epistemological challenges demand a critical understanding of the ethical system we live in - the ethics of exhaustion - to enable a comprehensive radical transformation of the consideration of energy futures, since epistemology is part of the formalization of ethics. This thesis argues that energy planning in Brazil is based on the ethics of exhaustion to epistemically impose the colonial agenda of power. Energy futures are planned as necessary harm to achieve the fetishized good, normalized as the ethical intersubjective and human-environment relationships. Critically analysing the ethical system enables understanding the epistemologies for energy planning in Brazil as the formal moment of the ethics of exhaustion, which can only be challenged in an intersectional manner by framing the multilateral and collateral aspects of the violence consistent in planning energy futures regardless and to the detriment of the existence of life. Epistemic diversity is the first step towards decolonizing energy planning. It comprises: the inclusion of indigenous and communal perspectives when elaborating the energy plans; having persons directly affected by energy enterprises as the majority of the personnel involved in the activity of planning; setting the priority of energy planning as the production and reproduction of all lives in a non-hierarchized manner; recognizing the necessary balance in the human-environment relationship; privileging local needs in relation to transnational markets; and intentionally de-hierarchizing the benefits of energy exploitation by delinking energy studies, production, and distribution from financial capital. This work challenges colonial epistemologies, based on the ethics of exhaustion, from the standpoint of the colonial difference, proposing epistemic diversity as the impulse for decolonial energy planning in Brazil. It is an urgent academic task to perceive epistemic decolonization to transform the present in order to stop condemning the future to social and environmental catastrophes.

Published
2019
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47. AB1115 VITAMIN D SUPPLEMENTATION PRESENTS A POSITIVE EFFECT ON MEMORY BUT NO EFFECT ON ANXIOUS-DEPRESSIVE BEHAVIOR IN A PRISTANE-INDUCED LUPUS MOUSE MODEL

Author

Karnopp, T. E., primary, Flores Chapacais, G., additional, Gasparini, M. L., additional, Garcia Dos Santos, N., additional, Da Silva Freitas, V., additional, Piccoli, M., additional, Leite DI Domenico, A., additional, Denardi Dória, L., additional, Pereira de Souza, N. M., additional, Correa Freitas, E., additional, Rieger, A., additional, and Monticielo, O. A., additional

Published
2024
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48. Proficiência digital e aprendizagem da história das entidades da enfermagem brasileira na pandemia

Author

Natália Maria Freitas e Silva Maia, Agostinho Antônio Cruz Araújo, Ana Maria Ribeiro dos Santos, Fernanda Batista Oliveira Santos, Pacita Geovana Gama de Sousa Aperibense, and Elaine Maria Leite Rangel Andrade

Subjects
Alfabetização digital, Tecnologia digital, Educação em enfermagem, Aprendizagem, História da enfermagem, Pandemias, Nursing, RT1-120
Abstract

Resumo Objetivo Caracterizar a proficiência digital e a aprendizagem de estudantes de enfermagem sobre a história das entidades de classe da enfermagem brasileira. Métodos Estudo exploratório-descritivo, transversal, realizado no curso de bacharelado em enfermagem, de três campi de uma instituição de ensino superior pública federal do Nordeste brasileiro. Aplicou-se, de novembro de 2020 a maio de 2021, questionário, via Google Forms, aos estudantes de enfermagem regularmente matriculados no segundo e terceiro períodos do curso. Realizou-se a análise estatística descritiva e inferencial. Resultados Participaram 56 estudantes de enfermagem, sendo 55,4% vinculados ao campus 1; 53,6% cursavam o terceiro semestre; 83,9% do sexo feminino; média idade de 20,55 (+3,32) anos; 55,4% pardos; 94,6% sem vínculo empregatício; 73,2% residindo com os pais; 92,9% com renda familiar mensal equivalente a três salários-mínimos. O grau de proficiência digital básico médio foi considerado baixo. Quanto às tecnologias digitais no ensino e à aprendizagem sobre história das entidades de classe, 62,5% acreditaram que contribuiria para aprendizagem, além do espaço da sala de aula, e facilitaria o acesso aos conteúdos; e 78,6% consideraram importante para desenvolver o senso crítico-reflexivo e a conscientização sobre a participação nessas entidades. Evidenciaram fundamental conhecer história da criação, contribuições, lutas, desafios e primeiras diretoras da Associação Brasileira de Enfermagem, além da criação dos Conselhos Federal e Regionais de Enfermagem e das respectivas atribuições. Conclusão As ações de ensino-aprendizagem, mediadas por tecnologias digitais, precisam considerar as competências digitais e os interesses dos estudantes na aprendizagem remota sobre história das entidades de classe da enfermagem.

Published
2023
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49. O açúcar amargo: Suor, sangue e lágrimas nos engenhos

Author

Rafael de Freitas e SOUZA

Subjects
Escravidão, engenho, trabalho, History (General), D1-2009
Abstract

Resumo As condições de vida e trabalho às quais foram submetidos homens e mulheres escravizados no processo produtivo do açúcar nos engenhos são fatores essenciais para entender a dinâmica da escravidão na América Portuguesa. Nas entrelinhas das recomendações e admoestações transmitidas aos senhores de engenhos do Nordeste, bem como nas descrições das tarefas executadas pelos escravos em diferentes setores da propriedade encontradas nos textos de clérigos setecentistas como padre Antônio Vieira, Jorge Benci, Manuel Ribeiro Rocha e, principalmente, por André João Antonil, é possível entrever essas condições e as relações de poder, que se vinham consolidando desde o século XVII. Frutos do estágio do desenvolvimento das forças produtivas no setor agrícola e de fatores inerentes ao escravismo moderno, essas condições permaneceram as mesmas no século XIX e podiam ser encontradas em outras regiões produtoras de açúcar no Sudeste, conforme se verifica nos relatos produzidos pelos viajantes europeus que visitaram essas propriedades.

Published
2023
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50. The Response of Paracoccidioides lutzii to the Interaction with Human Neutrophils

Author

Lana O’Hara Souza Silva, Lilian Cristiane Baeza, Laurine Lacerda Pigosso, Kleber Santiago Freitas e Silva, Maristela Pereira, Marcos Antonio Batista de Carvalho Júnior, and Célia Maria de Almeida Soares

Subjects
genus Paracoccidioides, human neutrophils, proteomics, metabolism shunt, stress response, Biology (General), QH301-705.5
Abstract

The fungal pathogen Paracoccidioides lutzii causes systemic mycosis Paracoccidioidomycosis (PCM), which presents a broad distribution in Latin America. Upon infection, the fungus undergoes a morphological transition to yeast cells and provokes an inflammatory granulomatous reaction with a high number of neutrophils in the lungs. In this work, we employed proteomic analysis to investigate the in vitro response of the fungus to the interaction with human neutrophils. Proteomic profiling of P. lutzii yeast cells harvested at 2 and 4 h post interaction with human polymorphonuclear cells allowed the identification of 505 proteins differentially accumulated. The data indicated that P. lutzii yeast cells underwent a shift in metabolism from glycolysis to Beta oxidation, increasing enzymes of the glyoxylate cycle and upregulating enzymes related to the detoxification of oxidative and heat shock stress. To our knowledge, this is the first study employing proteomic analysis in the investigation of the response of a member of the Paracoccidioides genus to the interaction with neutrophils.

Published
2023
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