Search

Your search keyword '"Pérez R"' showing total 7,789 results
Start Over Author "Pérez R"

Refine your results

more »

more »

more »

more »

more »

more »

more »
7,789 results on '"Pérez R"'

1. Benchmarking the design of the cryogenics system for the underground argon in DarkSide-20k

Author

Collaboration, DarkSide-20k, Acerbi, F., Adhikari, P., Agnes, P., Ahmad, I., Albergo, S., Albuquerque, I. F. M., Alexander, T., Alton, A. K., Amaudruz, P., Angiolilli, M., Aprile, E., Ardito, R., Corona, M. Atzori, Auty, D. J., Ave, M., Avetisov, I. C., Azzolini, O., Back, H. O., Balmforth, Z., Olmedo, A. Barrado, Barrillon, P., Batignani, G., Bhowmick, P., Blua, S., Bocci, V., Bonivento, W., Bottino, B., Boulay, M. G., Buchowicz, A., Bussino, S., Busto, J., Cadeddu, M., Cadoni, M., Calabrese, R., Camillo, V., Caminata, A., Canci, N., Capra, A., Caravati, M., Cárdenas-Montes, M., Cargioli, N., Carlini, M., Castellani, A., Castello, P., Cavalcante, P., Cebrian, S., Ruiz, J. Cela, Chashin, S., Chepurnov, A., Cifarelli, L., Cintas, D., Citterio, M., Cleveland, B., Coadou, Y., Cocco, V., Colaiuda, D., Vilda, E. Conde, Consiglio, L., Costa, B. S., Czubak, M., D'Aniello, M., D'Auria, S., Rolo, M. D. Da Rocha, Darbo, G., Davini, S., De Cecco, S., De Guido, G., Dellacasa, G., Derbin, A. V., Devoto, A., Di Capua, F., Di Ludovico, A., Di Noto, L., Di Stefano, P., Dias, L. K., Mairena, D. Díaz, Ding, X., Dionisi, C., Dolganov, G., Dordei, F., Dronik, V., Elersich, A., Ellingwood, E., Erjavec, T., Diaz, M. Fernandez, Ficorella, A., Fiorillo, G., Franchini, P., Franco, D., Gatti, H. Frandini, Frolov, E., Gabriele, F., Gahan, D., Galbiati, C., Galiński, G., Gallina, G., Gallus, G., Garbini, M., Abia, P. Garcia, Gawdzik, A., Gendotti, A., Ghisi, A., Giovanetti, G. K., Casanueva, V. Goicoechea, Gola, A., Grandi, L., Grauso, G., di Cortona, G. Grilli, Grobov, A., Gromov, M., Guerzoni, M., Gulino, M., Guo, C., Hackett, B. R., Hallin, A., Hamer, A., Haranczyk, M., Harrop, B., Hessel, T., Hill, S., Horikawa, S., Hu, J., Hubaut, F., Hucker, J., Hugues, T., Hungerford, E. V., Ianni, A., Ippolito, V., Jamil, A., Jillings, C., Jois, S., Kachru, P., Keloth, R., Kemmerich, N., Kemp, A., Kendziora, C. L., Kimura, M., Kish, A., Kondo, K., Korga, G., Kotsiopoulou, L., Koulosousas, S., Kubankin, A., Kunzé, P., Kuss, M., Kuźniak, M., Kuzwa, M., La Commara, M., Lai, M., Guirriec, E. Le, Leason, E., Leoni, A., Lidey, L., Lissia, M., Luzzi, L., Lychagina, O., Macfadyen, O., Machulin, I. N., Manecki, S., Manthos, I., Mapelli, L., Marasciulli, A., Mari, S. M., Mariani, C., Maricic, J., Martinez, M., Martoff, C. J., Matteucci, G., Mavrokoridis, K., McDonald, A. B., Mclaughlin, J., Merzi, S., Messina, A., Milincic, R., Minutoli, S., Mitra, A., Moharana, A., Moioli, S., Monroe, J., Moretti, E., Morrocchi, M., Mroz, T., Muratova, V. N., Murphy, M., Murra, M., Muscas, C., Musico, P., Nania, R., Nessi, M., Nieradka, G., Nikolopoulos, K., Nikoloudaki, E., Nowak, J., Olchanski, K., Oleinik, A., Oleynikov, V., Organtini, P., de Solórzano, A. Ortiz, Pallavicini, M., Pandola, L., Pantic, E., Paoloni, E., Papi, D., Pastuszak, G., Paternoster, G., Peck, A., Pegoraro, P. A., Pelczar, K., Pellegrini, L. A., Perez, R., Perotti, F., Pesudo, V., Piacentini, S. I., Pino, N., Plante, G., Pocar, A., Poehlmann, M., Pordes, S., Pralavorio, P., Price, D., Puglia, S., Bazetto, M. Queiroga, Ragusa, F., Ramachers, Y., Ramirez, A., Ravinthiran, S., Razeti, M., Renshaw, A. L., Rescigno, M., Retiere, F., Rignanese, L. P., Rivetti, A., Roberts, A., Roberts, C., Rogers, G., Romero, L., Rossi, M., Rubbia, A., Rudik, D., Sabia, M., Salomone, P., Samoylov, O., Sandford, E., Sanfilippo, S., Santone, D., Santorelli, R., Santos, E. M., Savarese, C., Scapparone, E., Schillaci, G., Schuckman II, F. G., Scioli, G., Semenov, D. A., Shalamova, V., Sheshukov, A., Simeone, M., Skensved, P., Skorokhvatov, M. D., Smirnov, O., Smirnova, T., Smith, B., Sotnikov, A., Spadoni, F., Spangenberg, M., Stefanizzi, R., Steri, A., Stornelli, V., Stracka, S., Sulis, S., Sung, A., Sunny, C., Suvorov, Y., Szelc, A. M., Taborda, O., Tartaglia, R., Taylor, A., Taylor, J., Tedesco, S., Testera, G., Thieme, K., Thompson, A., Thorpe, T. N., Tonazzo, A., Torres-Lara, S., Tricomi, A., Unzhakov, E. V., Vallivilayil, T. J., Van Uffelen, M., Velazquez-Fernandez, L., Viant, T., Viel, S., Vishneva, A., Vogelaar, R. B., Vossebeld, J., Vyas, B., Wada, M., Walczak, M. B., Wang, H., Wang, Y., Westerdale, S., Williams, L., Wojaczyński, R., Wojcik, M., Wojcik, M. M., Wright, T., Xiao, X., Xie, Y., Yang, C., Yin, J., Zabihi, A., Zakhary, P., Zani, A., Zhang, Y., Zhu, T., Zichichi, A., Zuzel, G., and Zykova, M. P.

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

DarkSide-20k (DS-20k) is a dark matter detection experiment under construction at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. It utilises ~100 t of low radioactivity argon from an underground source (UAr) in its inner detector, with half serving as target in a dual-phase time projection chamber (TPC). The UAr cryogenics system must maintain stable thermodynamic conditions throughout the experiment's lifetime of >10 years. Continuous removal of impurities and radon from the UAr is essential for maximising signal yield and mitigating background. We are developing an efficient and powerful cryogenics system with a gas purification loop with a target circulation rate of 1000 slpm. Central to its design is a condenser operated with liquid nitrogen which is paired with a gas heat exchanger cascade, delivering a combined cooling power of >8 kW. Here we present the design choices in view of the DS-20k requirements, in particular the condenser's working principle and the cooling control, and we show test results obtained with a dedicated benchmarking platform at CERN and LNGS. We find that the thermal efficiency of the recirculation loop, defined in terms of nitrogen consumption per argon flow rate, is 95 % and the pressure in the test cryostat can be maintained within $\pm$(0.1-0.2) mbar. We further detail a 5-day cool-down procedure of the test cryostat, maintaining a cooling rate typically within -2 K/h, as required for the DS-20k inner detector. Additionally, we assess the circuit's flow resistance, and the heat transfer capabilities of two heat exchanger geometries for argon phase change, used to provide gas for recirculation. We conclude by discussing how our findings influence the finalisation of the system design, including necessary modifications to meet requirements and ongoing testing activities., Comment: 45 pages, 24 figures

Published
2024

2. DarkSide-20k sensitivity to light dark matter particles

Author

Collaboration, DarkSide-20k, Acerbi, F., Adhikari, P., Agnes, P., Ahmad, I., Albergo, S., Albuquerque, I. F. M., Alexander, T., Alton, A. K., Amaudruz, P., Angiolilli, M., Aprile, E., Ardito, R., Corona, M. Atzori, Auty, D. J., Ave, M., Avetisov, I. C., Azzolini, O., Back, H. O., Balmforth, Z., Olmedo, A. Barrado, Barrillon, P., Batignani, G., Bhowmick, P., Blua, S., Bocci, V., Bonivento, W., Bottino, B., Boulay, M. G., Buchowicz, A., Bussino, S., Busto, J., Cadeddu, M., Cadoni, M., Calabrese, R., Camillo, V., Caminata, A., Canci, N., Capra, A., Caravati, M., Cárdenas-Montes, M., Cargioli, N., Carlini, M., Castellani, A., Castello, P., Cavalcante, P., Cebrian, S., Ruiz, J. M. Cela, Chashin, S., Chepurnov, A., Cifarelli, L., Cintas, D., Citterio, M., Cleveland, B., Coadou, Y., Cocco, V., Colaiuda, D., Vilda, E. Conde, Consiglio, L., Costa, B. S., Czubak, M., D'Aniello, M., D'Auria, S., Rolo, M. D. Da Rocha, Darbo, G., Davini, S., De Cecco, S., De Guido, G., Dellacasa, G., Derbin, A. V., Devoto, A., Di Capua, F., Di Ludovico, A., Di Noto, L., Di Stefano, P., Dias, L. K., Mairena, D. Díaz, Ding, X., Dionisi, C., Dolganov, G., Dordei, F., Dronik, V., Elersich, A., Ellingwood, E., Erjavec, T., Diaz, M. Fernandez, Ficorella, A., Fiorillo, G., Franchini, P., Franco, D., Gatti, H. Frandini, Frolov, E., Gabriele, F., Gahan, D., Galbiati, C., Galiński, G., Gallina, G., Gallus, G., Garbini, M., Abia, P. Garcia, Gawdzik, A., Gendotti, A., Ghisi, A., Giovanetti, G. K., Casanueva, V. Goicoechea, Gola, A., Grandi, L., Grauso, G., di Cortona, G. Grilli, Grobov, A., Gromov, M., Guerzoni, M., Gulino, M., Guo, C., Hackett, B. R., Hallin, A., Hamer, A., Haranczyk, M., Harrop, B., Hessel, T., Hill, S., Horikawa, S., Hu, J., Hubaut, F., Hucker, J., Hugues, T., Hungerford, E. V., Ianni, A., Ippolito, V., Jamil, A., Jillings, C., Jois, S., Kachru, P., Keloth, R., Kemmerich, N., Kemp, A., Kendziora, C. L., Kimura, M., Kondo, K., Korga, G., Kotsiopoulou, L., Koulosousas, S., Kubankin, A., Kunzé, P., Kuss, M., Kuźniak, M., Kuzwa, M., La Commara, M., Lai, M., Guirriec, E. Le, Leason, E., Leoni, A., Lidey, L., Lissia, M., Luzzi, L., Lychagina, O., Macfadyen, O., Machulin, I. N., Manecki, S., Manthos, I., Mapelli, L., Marasciulli, A., Mari, S. M., Mariani, C., Maricic, J., Martinez, M., Martoff, C. J., Matteucci, G., Mavrokoridis, K., McDonald, A. B., Mclaughlin, J., Merzi, S., Messina, A., Milincic, R., Minutoli, S., Mitra, A., Moioli, S., Monroe, J., Moretti, E., Morrocchi, M., Mroz, T., Muratova, V. N., Murphy, M., Murra, M., Muscas, C., Musico, P., Nania, R., Nessi, M., Nieradka, G., Nikolopoulos, K., Nikoloudaki, E., Nowak, J., Olchanski, K., Oleinik, A., Oleynikov, V., Organtini, P., de Solórzano, A. Ortiz, Pallavicini, M., Pandola, L., Pantic, E., Paoloni, E., Papi, D., Pastuszak, G., Paternoster, G., Peck, A., Pegoraro, P. A., Pelczar, K., Pellegrini, L. A., Perez, R., Perotti, F., Pesudo, V., Piacentini, S. I., Pino, N., Plante, G., Pocar, A., Poehlmann, M., Pordes, S., Pralavorio, P., Price, D., Puglia, S., Bazetto, M. Queiroga, Ragusa, F., Ramachers, Y., Ramirez, A., Ravinthiran, S., Razeti, M., Renshaw, A. L., Rescigno, M., Retiere, F., Rignanese, L. P., Rivetti, A., Roberts, A., Roberts, C., Rogers, G., Romero, L., Rossi, M., Rubbia, A., Rudik, D., Sabia, M., Salomone, P., Samoylov, O., Sandford, E., Sanfilippo, S., Santone, D., Santorelli, R., Santos, E. M., Savarese, C., Scapparone, E., Schillaci, G., Schuckman II, F. G., Scioli, G., Semenov, D. A., Shalamova, V., Sheshukov, A., Simeone, M., Skensved, P., Skorokhvatov, M. D., Smirnov, O., Smirnova, T., Smith, B., Sotnikov, A., Spadoni, F., Spangenberg, M., Stefanizzi, R., Steri, A., Stornelli, V., Stracka, S., Sulis, S., Sung, A., Sunny, C., Suvorov, Y., Szelc, A. M., Taborda, O., Tartaglia, R., Taylor, A., Taylor, J., Tedesco, S., Testera, G., Thieme, K., Thompson, A., Tonazzo, A., Torres-Lara, S., Tricomi, A., Unzhakov, E. V., Vallivilayil, T. J., Van Uffelen, M., Velazquez-Fernandez, L., Viant, T., Viel, S., Vishneva, A., Vogelaar, R. B., Vossebeld, J., Vyas, B., Walczak, M. B., Wang, Y., Wang, H., Westerdale, S., Williams, L., Wojaczyński, R., Wojcik, M., Wojcik, M. M., Wright, T., Xie, Y., Yang, C., Yin, J., Zabihi, A., Zakhary, P., Zani, A., Zhang, Y., Zhu, T., Zichichi, A., Zuzel, G., and Zykova, M. P.

Subjects
High Energy Physics - Experiment, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The dual-phase liquid argon time projection chamber is presently one of the leading technologies to search for dark matter particles with masses below 10 GeV/c$^2$. This was demonstrated by the DarkSide-50 experiment with approximately 50 kg of low-radioactivity liquid argon as target material. The next generation experiment DarkSide-20k, currently under construction, will use 1,000 times more argon and is expected to start operation in 2027. Based on the DarkSide-50 experience, here we assess the DarkSide-20k sensitivity to models predicting light dark matter particles, including Weakly Interacting Massive Particles (WIMPs) and sub-GeV/c$^2$ particles interacting with electrons in argon atoms. With one year of data, a sensitivity improvement to dark matter interaction cross-sections by at least one order of magnitude with respect to DarkSide-50 is expected for all these models. A sensitivity to WIMP--nucleon interaction cross-sections below $1\times10^{-42}$ cm$^2$ is achievable for WIMP masses above 800 MeV/c$^2$. With 10 years exposure, the neutrino fog can be reached for WIMP masses around 5 GeV/c$^2$., Comment: submitted to Nature Communications

Published
2024

3. Comparison of Visual Performance and Patient Satisfaction Outcomes with Two Trifocal IOLs with Similar Optical Design but Different Materials

Author

Poyales F, Pérez R, López-Brea I, Zhou Y, Rico L, and Garzón N

Subjects
trifocal finevision, intraocular lens, biomaterial, hydrophobic, hydrophilic, glistening-free, Ophthalmology, RE1-994
Abstract

Francisco Poyales,1 Ricardo Pérez,1 Israel López-Brea,1 Ying Zhou,1 Laura Rico,1 Nuria Garzón1,2 1Miranza IOA, Madrid, Spain; 2Optometry and Vision Department, Universidad Complutense, Madrid, SpainCorrespondence: Nuria GarzónMiranza IOA, C/Galileo 104, Madrid 28003, SpainTel +34 915353570Email nuria.garzon@miranza.esPurpose: To compare clinical outcomes in a prospective trial of cataract surgery patients bilaterally implanted with two different trifocal intraocular lenses (IOLs) with very similar optical designs but consisting of different IOL materials (hydrophobic and hydrophilic).Patients and Methods: Fifty-one patients (102 eyes) were randomized to receive trifocal IOLs bilaterally – FineVision POD F (hydrophilic) or FineVision POD F GF (hydrophobic) (both PhysIOL, Liége, Belgium). The follow-up period was 3 months. Outcome measurements included uncorrected distance (UDVA), corrected distance (CDVA), distance-corrected intermediate (DCIVA), and distance-corrected near visual acuity (DCNVA), refraction, negative dysphotopsia, optical quality of vision, contrast sensitivity under photopic and mesopic conditions, halometry (discrimination index), and patient-reported outcomes.Results: At the final study visit, mean (SD) values for binocular UDVA, CDVA, DCIVA (80 cm), and DCNVA (40 cm) were − 0.01 (0.06), − 0.04 (0.04), 0.09 (0.10), and 0.10 (0.09) logMAR, respectively, for POD F, and 0.01 (0.08), − 0.03 (0.03), 0.08 (0.1), and 0.13 (0.11) respectively, for POD F GF. Defocus assessments showed a continuous curve with a functional range of visual acuity (≤ 0.15 logMAR) from ∼ 30 cm to infinity in both groups. The discrimination index was > 0.85 for all patients, and both groups showed similar contrast sensitivity under photopic and mesopic conditions. At 3 months, no patient reported negative dysphotopsia, and high satisfaction rates were observed.Conclusion: Clinical outcomes showed no significant difference between each lens when measured at 1 month and 3 months after implantation. This equally good clinical performance of hydrophilic and hydrophobic trifocal lenses allows the surgeon to choose the IOL material based on personal preferences or patients’ needs.Keywords: trifocal FineVision, intraocular lens, biomaterial, hydrophobic, hydrophilic, glistening-free

Published
2020

4. A new hybrid gadolinium nanoparticles-loaded polymeric material for neutron detection in rare event searches

Author

Collaboration, DarkSide-20k, Acerbi, F., Adhikari, P., Agnes, P., Ahmad, I., Albergo, S., Albuquerque, I. F., Alexander, T., Alton, A. K., Amaudruz, P., Angiolilli, M., Aprile, E., Ardito, R., Corona, M. Atzori, Auty, D. J., Ave, M., Avetisov, I. C., Azzolini, O., Back, H. O., Balmforth, Z., Olmedo, A. Barrado, Barrillon, P., Batignani, G., Bhowmick, P., Bocci, V., Bonivento, W., Bottino, B., Boulay, M. G., Buchowicz, A., Bussino, S., Busto, J., Cadeddu, M., Cadoni, M., Calabrese, R., Camillo, V., Caminata, A., Canci, N., Capra, A., Caravati, M., Cárdenas-Montes, M., Cargioli, N., Carlini, M., Castellani, A., Castello, P., Cavalcante, P., Cavallo, D., Cebrian, S., Ruiz, J. Cela, Chashin, S., Chepurnov, A., Cifarelli, L., Cintas, D., Citterio, M., Cleveland, B., Coadou, Y., Cocco, V., Colaiuda, D., Vilda, E. Conde, Consiglio, L., Costa, B. S., Czubak, M., D'Auria, S., Rolo, M. D. Da Rocha, Darbo, G., Davini, S., De Cecco, S., De Guido, G., Dellacasa, G., Derbin, A. V., Devoto, A., Di Capua, F., Di Ludovico, A., Di Noto, L., Di Stefano, P., Dias, L. K., Mairena, D. Díaz, Ding, X., Dionisi, C., Dolganov, G., Dordei, F., Dronik, V., Elersich, A., Ellingwood, E., Erjavec, T., Diaz, M. Fernandez, Ficorella, A., Fiorillo, G., Franchini, P., Franco, D., Gatti, H. Frandini, Frolov, E., Gabriele, F., Gahan, D., Galbiati, C., Galinski, G., Gallina, G., Garbini, M., Abia, P. Garcia, Gawdzik, A., Gendotti, A., Ghisi, A., Giovanetti, G. K., Casanueva, V. Goicoechea, Gola, A., Grandi, L., Grauso, G., di Cortona, G. Grilli, Grobov, A., Gromov, M., Guerzoni, M., Gulino, M., Guo, C., Hackett, B. R., Hallin, A., Hamer, A., Haranczyk, M., Harrop, B., Hessel, T., Hill, S., Horikawa, S., Hu, J., Hubaut, F., Hucker, J., Hugues, T., Hungerford, E. V., Ianni, A., Ippolito, V., Jamil, A., Jillings, C., Keloth, R., Kemmerich, N., Kemp, A., Kendziora, C. L., Kimura, M., Kondo, K., Korga, G., Kotsiopoulou, L., Koulosousas, S., Kubankin, A., Kuss, M., Kuzniak, M., Kuzwa, M., La Commara, M., Lai, M., Guirriec, E. Le, Leason, E., Leoni, A., Lidey, L., Lissia, M., Luzzi, L., Lychagina, O., Macfadyen, O., Machulin, I. N., Manecki, S., Manthos, I., Mapelli, L., Marasciulli, A., Mari, S. M., Mariani, C., Maricic, J., Marini, A., Martinez, M., Martoff, C. J., Matteucci, G., Mavrokoridis, K., McDonald, A. B., Mclaughlin, J., Merzi, S., Messina, A., Milincic, R., Minutoli, S., Mitra, A., Moharana, A., Moioli, S., Monroe, J., Moretti, E., Morrocchi, M., Mroz, T., Muratova, V. N., Murphy, M., Murra, M., Muscas, C., Musico, P., Nania, R., Nessi, M., Nieradka, G., Nikolopoulos, K., Nikoloudaki, E., Nowak, J., Olchanski, K., Oleinik, A., Oleynikov, V., Organtini, P., de Solórzano, A. Ortiz, Pallavicini, M., Pandola, L., Pantic, E., Paoloni, E., Papi, D., Pastuszak, G., Paternoster, G., Peddis, D., Pegoraro, P. A., Pelczar, K., Pellegrini, L. A., Perez, R., Perotti, F., Pesudo, V., Piacentini, S. I., Pino, N., Plante, G., Pocar, A., Poehlmann, M., Pordes, S., Pralavorio, P., Price, D., Puglia, S., Bazetto, M. Queiroga, Ragusa, F., Ramachers, Y., Ramirez, A., Ravinthiran, S., Razeti, M., Renshaw, A. L., Rescigno, M., Retiere, F., Rignanese, L. P., Rivetti, A., Roberts, A., Roberts, C., Rogers, G., Romero, L., Rossi, M., Rubbia, A., Rudik, D., Sabia, M., Sadashivajois, S., Salomone, P., Samoylov, O., Sandford, E., Sanfilippo, S., Santone, D., Santorelli, R., Santos, E. M., Savarese, C., Scapparone, E., Schillaci, G., Schuckman II, F. G., Scioli, G., Semenov, D. A., Sheshukov, A., Simeone, M., Skensved, P., Skorokhvatov, M. D., Slimani, S., Smirnov, O., Smirnova, T., Smith, B., Sotnikov, A., Spadoni, F., Spangenberg, M., Stefanizzi, R., Steri, A., Stornelli, V., Stracka, S., Sulis, S., Sung, A., Sunny, C., Suvorov, Y., Szelc, A. M., Taborda, O., Tartaglia, R., Taylor, A., Taylor, J., Tedesco, S., Testera, G., Thieme, K., Thompson, A., Tonazzo, A., Torres-Lara, S., Tosi, S., Tricomi, A., Unzhakov, E. V., Vallivilayil, T. J., Van Uffelen, M., Velazquez-Fernandez, L., Viant, T., Vicini, S., Viel, S., Vishneva, A., Vogelaar, R. B., Vossebeld, J., Vyas, B., Wada, M., Walczak, M. B., Wang, H., Wang, Y., Westerdale, S., Williams, L., Wojaczynski, R., Wojcik, M. M., Wojcik, M., Wright, T., Xie, Y., Yang, C., Yin, J., Zabihi, A., Zakhary, P., Zani, A., Zhang, Y., Zhu, T., Zichichi, A., Zuzel, G., and Zykova, M. P.

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

Experiments aimed at direct searches for WIMP dark matter require highly effective reduction of backgrounds and control of any residual radioactive contamination. In particular, neutrons interacting with atomic nuclei represent an important class of backgrounds due to the expected similarity of a WIMP-nucleon interaction, so that such experiments often feature a dedicated neutron detector surrounding the active target volume. In the context of the development of DarkSide-20k detector at INFN Gran Sasso National Laboratory (LNGS), several R&D projects were conceived and developed for the creation of a new hybrid material rich in both hydrogen and gadolinium nuclei to be employed as an essential element of the neutron detector. Thanks to its very high cross-section for neutron capture, gadolinium is one of the most widely used elements in neutron detectors, while the hydrogen-rich material is instrumental in efficiently moderating the neutrons. In this paper results from one of the R&Ds are presented. In this effort the new hybrid material was obtained as a poly(methyl methacrylate) (PMMA) matrix, loaded with gadolinium oxide in the form of nanoparticles. We describe its realization, including all phases of design, purification, construction, characterization, and determination of mechanical properties of the new material.

Published
2024

10. Experimental and theoretical assessment of native oxide in the superconducting TaN

Author

Quintanar-Zamora, V., Cedillo-Rosillo, M., Contreras-López, O., Corona-García, C., Reyes-Serrato, A., Ponce-Pérez, R., Guerrero-Sánchez, J., and Díaz, J. A.

Subjects
Condensed Matter - Superconductivity, Condensed Matter - Materials Science
Abstract

In this manuscript, we show through an experimental-computational proof of concept the native oxide formation into superconducting TaN films. First, TaN was synthesized at an ultra-high vacuum system by reactive pulsed laser deposition and characterized in situ by X-ray photoelectron spectroscopy. The material was also characterized ex situ by X-ray diffraction, transmission electron microscopy, and the four-point probe method. It was detected that TaN contained considerable oxygen impurities (up to 26 %O) even though it was grown in an ultra-high vacuum chamber. Furthermore, the impurified TaN evidence a face-centered cubic crystalline structure only and exhibits superconductivity at 2.99 K. To understand the feasibility of the native oxide in TaN, we study the effect of incorporating different amounts of O atoms in TaN using ab-initio calculations. A thermodynamic stability analysis shows that a TaOxN1-x model increases its stability as oxygen is added, demonstrating that oxygen may always be present in TaN, even when obtained at ultra-high vacuum conditions. All analyzed models exhibit metallic behavior. Charge density difference maps reveal that N and O atoms have a higher charge density redistribution than Ta atoms. The electron localization function maps and line profiles indicate that Ta-O and Ta-N bonds are mainly ionic. As expected, stronger ionic behavior is observed in the Ta-O bonds due to the electronegativity difference between O and N atoms. Recent evidence points to superconductivity in bulk TaO, confirming the asseverations of superconductivity in our samples. The results discussed here highlight the importance of considering native oxide when reporting superconductivity in TaN films since the TaO regions formed in the compound may be key to understanding the different critical temperatures reported in the literature., Comment: 23 pages, 7 figures

Published
2023

11. Effect of interatomic repulsion on Majorana zero modes in a coupled quantum-dot-superconducting-nanowire hybrid system

Author

Perez, R. Kenyi Takagui and Aligia, A. A.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Superconductivity
Abstract

We study the low-energy eigenstates of a topological superconductor wire modeled by a Kitaev chain, which is connected at one of its ends to a quantum dot through nearest-neighbor (NN) hopping and NN Coulomb repulsion. Using an unrestricted Hartree-Fock approximation to decouple the Coulomb term, we obtain that the quality of the Majorana end states is seriously affected by this term only when the dependence of the low-lying energies with the energy of the quantum dot shows a "diamond" shape, characteristic of short wires. We discuss limitations of the simplest effective models to describe the physics. We expect the same behavior in more realistic models for topological superconducting wires., Comment: 7 pages, 7 figures, figures improved and more details provided

Published
2023
Full Text
View/download PDF

12. Optimized nuclear energy density functionals including long-range pion contributions

Author

Zurek, L., Bogner, S. K., Furnstahl, R. J., Pérez, R. Navarro, Schunck, N., and Schwenk, A.

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

Nuclear energy density functionals successfully reproduce properties of nuclei across almost the entire nuclear chart. However, nearly all available functionals are phenomenological in nature and lack a rigorous connection to systematically improvable nuclear forces. This issue might be solved with an energy density functional obtained from first principles. As an intermediate step towards this goal we construct the GUDE family of functionals that is obtained from a hybrid scheme consisting of long-range pion-exchange contributions derived from chiral effective field theory at the Hartree-Fock level and a phenomenological Skyrme part. When including pion contributions beyond next-to-leading order in the chiral expansion, we find significant improvements over a reference Skyrme functional constructed following the same protocol. We analyze the importance of different pion contributions and identify which terms drive the observed improvements. Since pions are incorporated without adding further optimization parameters to the functionals, the improvements can be attributed to the functional form of these terms. Our work therefore suggests that the considered chiral contributions constitute useful ingredients for true ab initio energy density functionals., Comment: 21 pages, 12 figures, corresponds to published version

Published
2023
Full Text
View/download PDF

17. Spatially-resolved properties of the ionized gas in the HII galaxy J084220+115000

Author

Fernández-Arenas, D., Carrasco, E., Terlevich, R., Terlevich, E., Amorín, R., Bresolin, F., Chávez, R., González-Morán, A. L., Rosa-González, D., Mayya, Y. D., Vega, O., Zaragoza-Cardiel, J., Méndez-Abreu, J., Izazaga-Pérez, R., de Paz, A. Gil, Gallego, J., Iglesias-Páramo, J., García-Vargas, M. L., Gómez-Alvarez, P., Castillo-Morales, A., Cardiel, N., Pascual, S., and Pérez-Calpena, A.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We present a spatially resolved spectroscopic study for the metal poor HII galaxy J084220+115000 using MEGARA Integral Field Unit observations at the Gran Telescopio Canarias. We estimated the gas metallicity using the direct method for oxygen, nitrogen and helium and found a mean value of 12+$\log$(O/H)=$8.03\pm$0.06, and integrated electron density and temperature of $\sim161$ cm$^{-3}$ and $\sim15400$ K, respectively. The metallicity distribution shows a large range of $\Delta$(O/H) = 0.72 dex between the minimum and maximum (7.69$\pm$0.06 and 8.42$\pm$0.05) values, unusual in a dwarf star-forming galaxy. We derived an integrated $\log$(N/O) ratio of $-1.51\pm0.05$ and found that both N/O and O/H correspond to a primary production of metals. Spatially resolved maps indicate that the gas appears to be photoionized by massive stars according to the diagnostic line ratios. Between the possible mechanisms to explain the starburst activity and the large variation of oxygen abundance in this galaxy, our data support a possible scenario where we are witnessing an ongoing interaction triggering multiple star-forming regions localized in two dominant clumps., Comment: 24 pages, 26 figures, Accepted for publication in MNRAS

Published
2022
Full Text
View/download PDF

18. ECONOMÍA ECOLÓGICA Y CONTABILIZACIÓN BIOFÍSICA: EL CASO DE LA ECONOMÍA COLOMBIANA Y SU COMERCIO EXTERIOR

Author

PÉREZ R. MARIO A.

Subjects
Geography. Anthropology. Recreation, Environmental sciences, GE1-350
Abstract

Desde la perspectiva de la Economía Ecológica, el Comercio Internacional no es un juego de suma positiva donde todos los participantes resultan ganadores, sino es un juego de suma cero donde hay beneficiados y perjudicados ecológicamente. El comercio internacional participa como un nuevo "vector ambiental", distribuyendo asimétricamente los costos ecológicos entre los países que comercian, siendo los países con abundancia de recursos naturales los que resultan perdedores en este intercambio. Las ventajas comparativas hacen que estos países se especialicen en la producción y exportación de bienes natural- intensivos e importen bienes capital- intensivos. Este patrón de especialización conlleva mayores costos ecológicos puesto que los recursos exportados no incluyen en los precios de exportación la pérdida, ni la depreciación del patrimonio ambiental. A su vez, los términos de intercambio del comercio internacional, junto a las relaciones desiguales de poder entre Norte y Sur, hacen que se requiera cada vez exportar y explotar más recursos naturales para obtener la misma cantidad de bienes importados. Esto es lo que se conoce como el intercambio ecológicamente desigual. Usando dos metodologías de cuantificación biofísica (Análisis de Flujo de Materiales y Huella Hídrica), este trabajo encuentra evidencia del intercambio desigual en términos ambientales que ha caracterizado al comercio exterior colombiano durante el periodo analizado.

Published
2008

20. Facilitators of Peer Leader Retention within a Type 2 Diabetes Intervention Trial for US Latinos/Hispanics of Mexican Origin

Author

Ayala, G. X., Canale, K., Ibarra, L., Parada, H., Crespo, N. C., Pérez, R., Horton, L. A., and Cherrington, A.

Abstract

Peer support is effective in improving self-management behaviors and health outcomes among individuals with Type 2 diabetes. Volunteer peer support programs offer a cost-effective resource for diabetes self-management support; however, factors affecting the retention of volunteer peer leaders remain understudied. Herein, we examined factors associated with volunteer retention and satisfaction among 34 predominantly Mexican-origin peer leaders who assisted patients from a Federally Qualified Health Center located on the US/Mexico border with their diabetes management. Peer leaders completed surveys with open- and close-ended questions at baseline, 6 months and 12 months. Quantitative and qualitative data analyses were guided by the Volunteer Process Model. Using nonparametric Mann-Whitney U tests, self-efficacy as a peer leader at 6 months was most associated with interest to continue volunteering (P = 0.01), and satisfaction with support from the program at 12 months was most associated with interest to continue volunteering (P = 0.01). The qualitative data indicated that the relationship between the peer leaders and their patients was the primary factor for a satisfying volunteer experience. Future research should focus on increasing peer leaders' self-efficacy and satisfaction with program support and examine how organizations can support the development of the patient--peer relationship. Practitioners should consider appealing to volunteer peers' motivations to promote their retention.

Published
2023
Full Text
View/download PDF

24. Formación en cirugía de cataratas en España: análisis de resultados de una encuesta del European Board of Ophthalmology en una cohorte española

Author

Yaïci, R., Martinez-Costa Pérez, R., Lefebvre, F., Muñoz Negrete, F., Ní Dhubhghaill, S., Sanogo, M., Aclimandos, W., Asoklis, R., Atilla, H., Creuzot-Garcher, C., Curtin, D., Cvenkel, B., Flanagan, L., Kivelä, T.T., Maino, A., Priglinger, S., Prior Filipe, H., Stopa, M., Strong, B., Sturmer, J., Tassignon, M.J., Ivekovic, R., and Bourcier, T.

Published
2024
Full Text
View/download PDF

25. Training in cataract surgery in Spain: analysis of the results of a survey of the European Board of Ophthalmology in a Spanish cohort

Author

Yaïci, R., Martinez-Costa Pérez, R., Lefebvre, F., Muñoz Negrete, F., Dhubhghaill, S. Ní, Sanogo, M., Aclimandos, W., Asoklis, R., Atilla, H., Creuzot-Garcher, C., Curtin, D., Cvenkel, B., Flanagan, L., Kivelä, T.T., Maino, A., Priglinger, S., Prior Filipe, H., Stopa, M., Strong, B., Sturmer, J., Tassignon, M.J., Ivekovic, R., and Bourcier, T.

Published
2024
Full Text
View/download PDF

28. Outcomes associated with ventilator-associated events (VAE), respiratory infections (VARI), pneumonia (VAP) and tracheobronchitis (VAT) in ventilated pediatric ICU patients: A multicentre prospective cohort study

Author

Abril-Molina, A., Alejandre, C., D., Arjona, Bustinza, A., Campins-Martí, M., Coca-Pérez, A., De Carlos, JC., Flores-González, JC., García-Besteiro, M., Jordán-García, I., López-Castilla, JD., Martínez-Padilla, MC., Mendizabal, M., Ortiz-Álvarez, A., Peña-López, Y., Pérez, E., Pérez, R., Pujol, M., Roca, D., Sánchez-Granados, JM., Sánchez-Pérez, S., Schüffelmann, C., Serrano-Megías, M., Slöcker-Barrio, M., Tejada, S., Rello, J., Peña-López, Yolanda, Slocker-Barrio, María, de-Carlos-Vicente, Juan-Carlos, Serrano-Megías, Marta, Jordán-García, Iolanda, and Rello, Jordi

Published
2024
Full Text
View/download PDF

30. [Translated article] Standard and Expanded Series Patch Testing Update by the Spanish Contact Dermatitis and Skin Allergy Research Group (GEIDAC)

Author

Navarro-Triviño, F.J., Borrego, L., Silvestre-Salvador, J.F., Mercader-García, P., Giménez-Arnau, A.M., Ortiz-de Frutos, F.J., Sanz-Sánchez, T., Melé-Ninot, G., Sánchez-Gilo, A., Zaragoza-Ninet, V., Serra-Baldrich, E., Miquel-Miquel, J., Córdoba-Guijarro, S., Rodríguez-Serna, M., Ruíz-González, I., Carrascosa-Carrillo, J.M., Gómez-de la Fuente, E., Pastor-Nieto, M.A., Heras-Mendaza, F., González-Pérez, R., Sánchez-Pedreño Guillén, P., Sánchez-Pérez, J., Gatica-Ortega, M.E., Fernández-Redondo, V., Hervella-Garcés, M., Manrique-Martínez, P., Guimaraens-Juanena, D., García-Gavín, J., Giménez-Arnau, E., Figueras-Nart, I., Curto-Barredo, L., and Armario-Hita, J.C.

Published
2024
Full Text
View/download PDF

31. Actualización de la batería estándar y batería ampliada de pruebas alérgicas de contacto por el Grupo Español de Investigación en Dermatitis de Contacto y Alergia Cutánea (GEIDAC)

Author

Navarro-Triviño, F.J., Borrego, L., Silvestre-Salvador, J.F., Mercader-García, P., Giménez-Arnau, A.M., Ortiz-de Frutos, F.J., Sanz-Sánchez, T., Melé-Ninot, G., Sánchez-Gilo, A., Zaragoza-Ninet, V., Serra-Baldrich, E., Miquel-Miquel, J., Córdoba-Guijarro, S., Rodríguez-Serna, M., Ruíz-González, I., Carrascosa-Carrillo, J.M., Gómez-de la Fuente, E., Pastor-Nieto, M.A., Heras-Mendaza, F., González-Pérez, R., Sánchez-Pedreño Guillén, P., Sánchez-Pérez, J., Gatica-Ortega, M.E., Fernández-Redondo, V., Hervella-Garcés, M., Manrique-Martínez, P., Guimaraens-Juanena, D., García-Gavín, J., Giménez-Arnau, E., Figueras-Nart, I., Curto-Barredo, L., and Armario-Hita, J.C.

Published
2024
Full Text
View/download PDF

32. Self-energy corrected band-gap tuning induced by strain in the hexagonal boron phosphide monolayer

Author

Hernandez, Jose Mario Galicia, Sanchez, J. Guerrero, Perez, R. Ponce, Escamilla, H. N. Fernandez, Cocoletzi, Gregorio H., and Takeuchi, Noboru

Subjects
Condensed Matter - Materials Science
Abstract

We performed a first-principles study of the electronic behavior of a 2D hexagonal boron phosphide monolayer (2D-h-BP). The system was deformed isotropically by applying a simultaneous tensile strain along the a and b crystal axes. We analyzed the band-gap evolution as function of the deformation percentage, ranging from 1% to 8%. Results show that the system behaves as a direct band-gap semiconductor, with the valence band maximum and conduction band minimum located at the K point (1/3, 1/3, 0) of the Brillouin zone. This behavior is unchanged despite the strain application. The band gap underestimation, as computed within the standard DFT, was corrected by applying the G0W0 approach. Trends in the band-gap behavior are the same within both approaches: for low deformation percentages, the band-gap grows linearly with a small slope, and at higher values, it grows very slow with a tendency to achieve saturation. Therefore, the band-gap is less sensitive to tensile strain for deformations near 8%. The origin of this band gap behavior is explained in terms of the projected density of states and charge densities, and it can be attributed to Coulomb interactions, and charge redistributions due to the applied tensile strain. To study the carrier mobility, we computed the electron and hole effective masses, finding high mobility for both carriers. Finally, the stability analysis of each strained system includes the calculation of phonon spectra, to assure the dynamical stability, the computation of elastic constants to evaluate the mechanical stability, and cohesive energies for exploring the thermodynamical stability. Results indicate that the boron phosphide monolayer is stable under the calculated tensile strains., Comment: Submitted to: Computational Materials Science on May 24th, 2021 (Ms. Ref. No.: COMMAT-D-21-01286) Submitted for revisions on August 21th, 2021 (Ref. No.: COMMAT-D-21-01286R1)

Published
2021

33. A new insight of AGC198691 (Leoncino) galaxy with MEGARA at the GTC

Author

Carrasco, E., García-Vargas, M. L., de Paz, A. Gil, Mollá, M., Izazaga-Pérez, R., Castillo-Morales, A., Gómez-Alvarez, P., Gallego, J., Iglesias-Páramo, J., Cardiel, N., Pascual, S., and Pérez-Calpena, A.

Subjects
Astrophysics - Astrophysics of Galaxies
Abstract

We describe the observations of the low-metallicity nearby galaxy AGC198691 (Leoncino dwarf) obtained with the Integral Field Unit of the instrument MEGARA at the Gran Telescopio Canarias. The observations cover the wavelength ranges 4304 - 5198 A and 6098 - 7306 A with a resolving power R ~ 6000. We present 2D maps of the ionized gas, deriving the extension of the HII region and gas kinematics from the observed emission lines. We have not found any evidence of recent gas infall or loss of metals by means of outflows. This result is supported by the closed-box model predictions, consistent with the oxygen abundance found by other authors in this galaxy and points towards Leoncino being a genuine XMD galaxy. We present for the first time spatially resolved spectroscopy allowing the detailed study of a star forming region. We use PopStar+Cloudy models to simulate the emission-line spectrum. We find that the central emission line spectrum can be explained by a single young ionizing cluster with an age ~ 3.5 +/- 0.5Myr and a stellar mass of about 2000 solar masses. However, the radial profiles of [OIII]5007 A and the Balmer lines in emission demand photoionization by clusters of different ages between 3.5 and 6.5Myr that might respond either to the evolution of a single cluster evolving along the cooling time of the nebula (about 3Myr at the metallicity of Leoncino, Z ~ 0.0004) or to mass segregation of the cluster, being both scenarios consistent with the observed equivalent widths of the Balmer lines, Comment: 23 pages, 18 figures, Accepted in MNRAS on November 6, 2021

Published
2021
Full Text
View/download PDF

34. Axially-deformed solution of the Skyrme-Hartree-Fock-Bogoliubov equations using the transformed harmonic oscillator basis (IV) hfbtho (v4.0): A new version of the program

Author

Marevic, P., Schunck, N., Ney, E. M., Pérez, R. Navarro, Verriere, M., and O'Neal, J.

Subjects
Nuclear Theory
Abstract

We describe the new version 4.0 of the code hfbtho that solves the nuclear Hartree-Fock-Bogoliubov problem by using the deformed harmonic oscillator basis in cylindrical coordinates. In the new version, we have implemented the restoration of rotational, particle number, and reflection symmetry. The restoration of rotational symmetry does not require using bases closed under rotation. Furthermore, the SeaLL1 functional was added and the calculation of the Coulomb potential was improved. Finally, the code has been refactored to facilitate maintenance and future developments., Comment: 21 pages, 7 figures, 2 tables

Published
2021
Full Text
View/download PDF

40. [Translated article] Epidemiological, Clinical, and Allergic Profile of Psoriatic Patients. Evaluation of the Spanish Registry of Contact Dermatitis and Cutaneous Allergy (REIDAC)

Author

Verdaguer-Faja, J., Borrego, L., Mercader-García, P., González Pérez, R., Córdoba-Guijarro, S., Giménez-Arnau, A.M., Ruiz-González, I., Miquel-Miquel, J., Silvestre, J.F., Ortiz de Frutos, F.J., Tous-Romero, F., Sanz Sánchez, T., Rodríguez-Serna, M., Sánchez-Pérez, J., Serra Baldrich, E., Zaragoza-Ninet, V., Pastor-Nieto, M.A., Gática-Ortega, M.E., Sánchez Gilo, A., Melé-Ninot, G., Sánchez-Pedreño Guillén, P., Munera-Campos, M., Descalzo, M.Á., García-Doval, I., and Carrascosa, J.M.

Published
2024
Full Text
View/download PDF

41. Perfil epidemiológico, clínico y alérgico en pacientes con psoriasis. Evaluación del Registro Español de Dermatitis de Contacto (REIDAC)

Author

Verdaguer-Faja, J., Borrego, L., Mercader-García, P., González Pérez, R., Córdoba-Guijarro, S., Giménez-Arnau, A.M., Ruiz-González, I., Miquel-Miquel, J., Silvestre, J.F., Ortiz de Frutos, F.J., Tous-Romero, F., Sanz Sánchez, T., Rodríguez-Serna, M., Sánchez-Pérez, J., Serra Baldrich, E., Zaragoza-Ninet, V., Pastor-Nieto, M.A., Gática-Ortega, M.E., Sánchez Gilo, A., Melé-Ninot, G., Sánchez-Pedreño Guillén, P., Munera-Campos, M., Descalzo, M.Á., García-Doval, I., and Carrascosa, J.M.

Published
2024
Full Text
View/download PDF

43. Costs and resource utilization patterns in surgical site infections: a pre-COVID-19 perspective from France, Germany, Spain, and the UK

Author

Pegeot, A., Durand, H., Ménard, A., Potart, A., Porché, C., Hallouin-Bernard, M.C., Moreno, A.V., Solá, M., Onori, R., Goia, F., Escudero, R., Martínez-Morel, H., Luján, M., Pérez, R., Panes, A., Rhodes, K., Koll, C.E.M., Koehler, F.C., Cornely, F.B., Budin, S., Salmanton-García, J., Bruns, C., Rutz, J., Albertsmeier, M., Ankert, J., Bernard, L., Bataille, C., Couvé-Deacon, E., Fernández-Ferrer, M., Fortún, J., Galar, A., Grill, E., Guimard, T., Classen, A.Y., Vehreschild, J.J., Stemler, J., Naendrup, J-H., Hampl, J., Tallon, B., Sprute, R., Horcajada, J.P., Mollar-Maseres, J., Muñoz, P., Pletz, M.W., Serracino-Inglott, F., Soriano, A., Vilz, T.O., Seifert, H., Cornely, O.A., Mellinghoff, S.C., Liss, B.J., and Wingen-Heimann, S.M.

Published
2024
Full Text
View/download PDF

45. [Translated article] Four-year Epidemiological Surveillance of the Spanish Registry of Research in Contact Dermatitis and Cutaneous Allergy: Current Situation and Trends

Author

Tous-Romero, F., Borrego-Hernando, L., García-Doval, I., Mercader-García, P., Silvester-Salvador, J.F., Sánchez-Gilo, A., Sanz-Sánchez, T., Giménez-Arnau, A.M., Zaragoza-Ninet, V., Miquel-Miquel, J., González Pérez, R., Córdoba-Guijarro, S., Carrascosa-Carrillo, J.M., Gática-Ortega, M.E., Ruíz-González, I., Serra-Baldrich, E., Pastor-Nieto, A., Rodríguez-Serna, M., Sánchez-Pérez, J., Melé i Ninot, G., Sánchez-Pedreño Guillén, P., and Ortiz-de Frutos, J.

Published
2024
Full Text
View/download PDF

46. Vigilancia epidemiológica en los últimos 4 años del Registro Español de Investigación en Dermatitis de Contacto y Alergia Cutánea: situación actual y tendencias

Author

Tous-Romero, F., Borrego-Hernando, L., García-Doval, I., Mercader-García, P., Silvester-Salvador, J.F., Sánchez-Gilo, A., Sanz-Sánchez, T., Giménez-Arnau, A.M., Zaragoza-Ninet, V., Miquel-Miquel, J., González Pérez, R., Córdoba-Guijarro, S., Carrascosa-Carrillo, J.M., Gática-Ortega, M.E., Ruíz-González, I., Serra-Baldrich, E., Pastor-Nieto, A., Rodríguez-Serna, M., Sánchez-Pérez, J., Melé i Ninot, G., Sánchez-Pedreño Guillén, P., and Ortiz-de Frutos, J.

Published
2024
Full Text
View/download PDF

48. Consideraciones morfotaxonómicas sobre 'Orbulina universa' d'Orbigny (foraminiferida) Consideraciones morfotaxonómicas sobre 'Orbulina universa' d'Orbigny (foraminiferida)

Author

Parada Ruffinatti Carmen, Pérez R. Valdemar, and Sánchez Carlos Alberto

Subjects
Orbulina universa d'Orbigny, Vida planctónica, Foraminiferida, Morfotaxonomía, Globigerina, Globigerinoides, Hastigerina, Foraminífero planctónico, Science, Zoology, QL1-991, Botany, QK1-989
Abstract

Se examinan 1.072 ejemplares de Orbulina universa d'Orbigny. En el interior de un 12% de ellos se identifica un foraminífero planctónico, adherido mediante espinas y perteneciente a alguno de los géneros Globigerina, Globigerinoides y Hastigerina. Se plantea una hipótesis sobre el papel que desempeña esta cámara esférica en el ciclo vital de estos foraminíferos y se concluye que Orbulina no es un género, sino una forma transitoria en varios foraminíferos de vida planctónica. 1.072 specimens of Orbulina universa d'Orbigny are examined. A planktonic foraminifer, with adherent spines, belonging to the genera Gfobigerina, Globigerinoides and Hastigerina is identified inside of a 12% of the shells. An hypothesis about the roll of performance of this sphaerical chamber, in the vital cycle of this planktonic foraminifera, is stablished. The final conclusion is that Orbulina is not a genus but a transitory form in various foraminifera of planktonic life.

Published
1991

Catalog

Books, media, physical & digital resources
See catalog results