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Authors = David Martin-Marrero

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13 pages, 1999 KiB  
Article
Seven Epidemic Waves of COVID-19 in a Hospital in Madrid: Analysis of Severity and Associated Factors
by Juan Víctor San Martín-López, Nieves Mesa, David Bernal-Bello, Alejandro Morales-Ortega, Marta Rivilla, Marta Guerrero, Ruth Calderón, Ana I. Farfán, Luis Rivas, Guillermo Soria, Aída Izquierdo, Elena Madroñal, Miguel Duarte, Sara Piedrabuena, María Toledano-Macías, Jorge Marrero, Cristina de Ancos, Begoña Frutos, Rafael Cristóbal, Laura Velázquez, Belén Mora, Paula Cuenca, José Á. Satué, Ibone Ayala-Larrañaga, Lorena Carpintero, Celia Lara, Álvaro R. Llerena, Virginia García, Vanessa García de Viedma, Santiago Prieto, Natalia González-Pereira, Cristina Bravo, Carolina Mariño, Luis Antonio Lechuga, Jorge Tarancón, Sonia Gonzalo, Santiago Moreno and José M. Ruiz-Giardinadd Show full author list remove Hide full author list
Viruses 2023, 15(9), 1839; https://doi.org/10.3390/v15091839 - 30 Aug 2023
Cited by 7 | Viewed by 1905
Abstract
(1) Background: COVID-19 has evolved during seven epidemic waves in Spain. Our objective was to describe changes in mortality and severity in our hospitalized patients. (2) Method: This study employed a descriptive, retrospective approach for COVID-19 patients admitted to the Hospital de Fuenlabrada [...] Read more.
(1) Background: COVID-19 has evolved during seven epidemic waves in Spain. Our objective was to describe changes in mortality and severity in our hospitalized patients. (2) Method: This study employed a descriptive, retrospective approach for COVID-19 patients admitted to the Hospital de Fuenlabrada (Madrid, Spain) until 31 December 2022. (3) Results: A total of 5510 admissions for COVID-19 were recorded. The first wave accounted for 1823 (33%) admissions and exhibited the highest proportion of severe patients: 65% with bilateral pneumonia and 83% with oxygen saturation under 94% during admission and elevated levels of CRP, IL-6, and D-dimer. In contrast, the seventh wave had the highest median age (79 years) and comorbidity (Charlson: 2.7), while only 3% of patients had bilateral pneumonia and 3% required intubation. The overall mortality rate was 10.3%. The first wave represented 39% of the total. The variables related to mortality were age (OR: 1.08, 1.07–1.09), cancer (OR: 1.99, 1.53–2.60), dementia (OR: 1.82, 1.20–2.75), the Charlson index (1.38, 1.31–1.47), the need for high-flow oxygen (OR: 6.10, 4.94–7.52), mechanical ventilation (OR: 11.554, 6.996–19.080), and CRP (OR: 1.04, 1.03–1.06). (4) Conclusions: The variables associated with mortality included age, comorbidity, respiratory failure, and inflammation. Differences in the baseline characteristics of admitted patients explained the differences in mortality in each wave. Differences observed between patients admitted in the latest wave and the earlier ones suggest that COVID-19 has evolved into a distinct disease, requiring a distinct approach. Full article
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12 pages, 2860 KiB  
Article
Geometric Method: A Novel, Fast and Accurate Solution for the Inverse Problem in Risley Prisms
by Juan Domingo Sandoval, Keyla Delgado, David Fariña, Fernando de la Puente, Roberto Esper-Chaín and Marrero Martín
Appl. Sci. 2022, 12(21), 11087; https://doi.org/10.3390/app122111087 - 1 Nov 2022
Cited by 4 | Viewed by 2964
Abstract
Today, mechanical tracking systems are becoming increasingly compact, enabling a new range of civil and military applications. These include aerial laser scanning, for which Risley prisms are used. In Risley systems, the so-called inverse problem, which focuses on obtaining the angles of the [...] Read more.
Today, mechanical tracking systems are becoming increasingly compact, enabling a new range of civil and military applications. These include aerial laser scanning, for which Risley prisms are used. In Risley systems, the so-called inverse problem, which focuses on obtaining the angles of the prisms for a given target coordinate, has not yet been solved mathematically. As a consequence, approximate approaches have been used, but the solutions obtained have significant errors and a lack of precision. To improve accuracy, iterative methods, which are computationally intensive, have also been implemented. In this paper, an analytical process which we call the geometric method is presented, and we verified that this strategy highly improves accuracy and computational speed. Using this method in an iterative process gives accuracies of up to 1 pm in only three iterations. This high accuracy would allow the geometric method to be applied in fields such as lithography, stereolithography, or 3D printing. Full article
(This article belongs to the Collection Optical Design and Engineering)
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12 pages, 1013 KiB  
Article
Comparative Study of Vaccinated and Unvaccinated Hospitalised Patients: A Retrospective Population Study of 500 Hospitalised Patients with SARS-CoV-2 Infection in a Spanish Population of 220,000 Inhabitants
by José M. Ruiz-Giardin, Marta Rivilla, Nieves Mesa, Alejandro Morales, Luis Rivas, Aída Izquierdo, Almudena Escribá, Juan V. San Martín, David Bernal-Bello, Elena Madroñal, Ana I. Farfán, Marta Guerrero, Ruth Calderón, Miguel A. Duarte, Sara I. Piedrabuena, María Toledano-Macías, José Á. Satué, Jorge Marrero, Cristina L. de Ancos, Begoña Frutos, Rafael Cristóbal, Guillermo Soria, Ibone Ayala-Larrañaga, Lorena Carpintero, Miguel de Hita, Celia Lara, Álvaro R. Llerena, Virginia García, Raquel Jiménez, Vanesa García, Elena M. Saiz-Lou, Santiago Prieto, Natalia González-Pereira, Luis Antonio Lechuga, Jorge Tarancón and Sonia Gonzaloadd Show full author list remove Hide full author list
Viruses 2022, 14(10), 2284; https://doi.org/10.3390/v14102284 - 17 Oct 2022
Cited by 10 | Viewed by 3388
Abstract
Objectives. This study aimed to compare the characteristics of fully and partially vaccinated or unvaccinated coronavirus disease 2019 (COVID-19) patients who were hospitalised in a population of 220,000 habitants. Methods: Retrospective, observational, and population studies were conducted on patients who were hospitalised due [...] Read more.
Objectives. This study aimed to compare the characteristics of fully and partially vaccinated or unvaccinated coronavirus disease 2019 (COVID-19) patients who were hospitalised in a population of 220,000 habitants. Methods: Retrospective, observational, and population studies were conducted on patients who were hospitalised due to COVID-19 from March to October 2021. We assessed the impact of vaccination and other risk factors through Cox multivariate analysis. Results: A total of 500 patients were hospitalised, among whom 77 (15.4%) were fully vaccinated, 86 (17.2%) were partially vaccinated, and 337 (67.4%) were unvaccinated. Fully vaccinated (FV) patients were older and had a higher Charlson index than those of partially vaccinated and unvaccinated patients (NFV). Bilateral pneumonia was more frequent among NFV (259/376 (68.9%)) than among FV patients (32/75 (42.7%)). The former had more intensive care unit admissions (63/423) than the latter (4/77); OR: 2.80; CI (1.07–9.47). Increasing age HZ: 1.1 (1.06–1.14)) and haematological disease at admission HZ: 2.99 (1.26–7.11)) were independent risk factors for higher mortality during the first 30 days of hospitalisation. The probability of an earlier discharge in the subgroup of 440 patients who did not die during the first 30 days of hospitalisation was related to age (older to younger: HZ: 0.98 (0.97–0.99)) and vaccination status. Conclusions: Among the patients hospitalised because of COVID-19, complete vaccination was associated with less severe forms of COVID-19, with an earlier discharge date. Age and haematological disease were related to a higher mortality rate during the first 30 days of hospitalisation. Full article
(This article belongs to the Special Issue State-of-the-Art SARS-CoV-2 Research in Spain)
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18 pages, 3026 KiB  
Concept Paper
U-Space Concept of Operations: A Key Enabler for Opening Airspace to Emerging Low-Altitude Operations
by Cristina Barrado, Mario Boyero, Luigi Brucculeri, Giancarlo Ferrara, Andrew Hately, Peter Hullah, David Martin-Marrero, Enric Pastor, Anthony Peter Rushton and Andreas Volkert
Aerospace 2020, 7(3), 24; https://doi.org/10.3390/aerospace7030024 - 7 Mar 2020
Cited by 163 | Viewed by 16593
Abstract
Opening the sky to new classes of airspace user is a political and economic imperative for the European Union. Drone industries have a significant potential for economical growth according to the latest estimations. To enable this growth safely and efficiently, the CORUS project [...] Read more.
Opening the sky to new classes of airspace user is a political and economic imperative for the European Union. Drone industries have a significant potential for economical growth according to the latest estimations. To enable this growth safely and efficiently, the CORUS project has developed a concept of operations for drones flying in Europe in very low-level airspace, which they have to share that space with manned aviation, and quite soon with urban air mobility aircraft as well. U-space services and the development of smart, automated, interoperable, and sustainable traffic management solutions are presented as the key enabler for achieving this high level of integration. In this paper, we present the U-space concept of operations (ConOps), produced around three new types of airspace volume, called X, Y, and Z, and the relevant U-space services that will need to be supplied in each of these. The paper also describes the reference high-level U-space architecture using the European air traffic management architecture methodology. Finally, the paper proposes the basis for the aircraft separation standards applicable by each volume, to be used by the conflict detection and resolution services of U-space. Full article
(This article belongs to the Special Issue Unmanned Aircraft Traffic Management)
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