Control de robots móviles mediante visión omnidireccional utilizando la geometría de tres vistas

Este trabajo trata acerca del control visual de robot móviles. Dentro de este campo tan amplio de investigación existen dos elementos a los que prestaremos especial atención: la visión omnidireccional y los modelos geométricos multi-vista. Las cámaras omnidireccionales proporcionan información angular muy precisa, aunque presentan un grado de distorsión significativo en dirección radial. Su cualidad de poseer un amplio campo de visión hace que dichas cámaras sean apropiadas para tareas de navegación robótica. Por otro lado, el uso de los modelos geométricos que relacionan distintas vistas de una escena permite rechazar emparejamientos erróneos de características visuales entre imágenes, y de este modo robustecer el proceso de control mediante visión. Nuestro trabajo presenta dos técnicas de control visual para ser usadas por un robot moviéndose en el plano del suelo. En primer lugar, proponemos un nuevo método para homing visual, que emplea la información dada por un conjunto de imágenes de referencia adquiridas previamente en el entorno, y las imágenes que toma el robot a lo largo de su movimiento. Con el objeto de sacar partido de las cualidades de la visión omnidireccional, nuestro método de homing es puramente angular, y no emplea información alguna sobre distancia. Esta característica, unida al hecho de que el movimiento se realiza en un plano, motiva el empleo del modelo geométrico dado por el tensor trifocal 1D. En particular, las restricciones geométricas impuestas por dicho tensor, que puede ser calculado a partir de correspondencias de puntos entre tres imágenes, mejoran la robustez del control en presencia de errores de emparejamiento. El interés de nuestra propuesta reside en que el método de control empleado calcula las velocidades del robot a partir de información únicamente angular, siendo ésta muy precisa en las cámaras omnidireccionales. Además, presentamos un procedimiento que calcula las relaciones angulares entre las vistas disponibles de manera indirecta, sin necesidad de que haya información visual compartida entre todas ellas. La técnica descrita se puede clasificar como basada en imagen (image-based), dado que no precisa estimar la localización ni utiliza información 3D. El robot converge a la posición objetivo sin conocer la información métrica sobre la trayectoria seguida. Para algunas aplicaciones, como la evitación de obstáculos, puede ser necesario disponer de mayor información sobre el movimiento 3D realizado. Con esta idea en mente, presentamos un nuevo método de control visual basado en entradas sinusoidales. Las sinusoides son funciones con propiedades matemáticas bien conocidas y de variación suave, lo cual las hace adecuadas para su empleo en maniobras de aparcamiento de vehículos. A partir de las velocidades de variación sinusoidal que definimos en nuestro diseño, obtenemos las expresiones analíticas de la evolución de las variables de estado del robot. Además, basándonos en dichas expresiones, proponemos un método de control mediante realimentación del estado. La estimación del estado del robot se obtiene a partir del tensor trifocal 1D calculado entre la vista objetivo, la vista inicial y la vista actual del robot. Mediante este control sinusoidal, el robot queda alineado con la posición objetivo. En un segundo paso, efectuamos la corrección de la profundidad mediante una ley de control definida directamente en términos del tensor trifocal 1D. El funcionamiento de los dos controladores propuestos en el trabajo se ilustra mediante simulaciones, y con el objeto de respaldar su viabilidad se presentan análisis de estabilidad y resultados de simulaciones y de experimentos con imágenes reales

Nutrición enteral domiciliaria en España: registro Nadya del año 2011-2012

Objective: To describe the results of the home enteral nutrition (HEN) registry of the NADYA-SENPE group in 2011 and 2012. Material and methods: We retrieved the data of the patients recorded from January 1st 2011 to December 31st 2012. Results: There were 3021 patients in the registry during the period from 29 hospitals, which gives 65.39 per million inhabitants. 97.95% were adults, 51.4% male. Mean age was 67.64 ± 19.1, median age was 72 years for adults and 7 months for children. Median duration with HEN was 351 days and for 97.5% was their first event with HEN. Most patients had HEN because of neurological disease (57.8%). Access route was nasogastric tube for 43.5% and gastrostomy for 33.5%. Most patients had limited activity level and, concerning autonomy, 54.8% needed total help. Nutritional formula was supplied from chemist’s office to 73.8% of patients and disposables, when necessary, was supplied from hospitals to 53.8% of patients. HEN was finished for 1,031 patients (34.1%) during the period of study, 56.6% due to decease and 22.2% due to recovery of oral intake. Conclusions: Data from NADYA-SENPE registry must be explained cautiously because it is a non-compulsory registry. In spite of the change in the methodology of the registry in 2010, tendencies regarding HEN have been maintained, other than oral routeObjetivos: Describir los resultados del registro de nutrición enteral domiciliaria (NED) del grupo NADYASENPE de los años 2011 y 12. Material y métodos: Se recopilaron los datos introducidos en el registro desde el 1 de enero de 2011 al 31 de diciembre de 2012. Resultados: Hubo 3021 pacientes en el registro durante el periodo, procedentes de 29 hospitales, lo que da una prevalencia de 65,39 casos por millón de habitantes. 97.95% fueron adultos, 51,4% varones. La edad media fue 67,64 ± 19,1 años y la mediana 72 años para los adultos y 7 meses para los niños. La duración media de la NED fue 351 días y para el 97,5% fue el primer episodio con NED. La mayoría de pacientes tenían NED por una enfermedad neurológica (57,8%). La vía de acceso fue sonda nasogástrica para el 43,5% y gastrostomía para el 33,5%. La mayoría de pacientes tuvieron un nivel de actividad física limitado y, respecto a la autonomía, 54,8% necesitaba ayuda total. La fórmula de nutrición se suministró desde las oficinas de farmacia para el 73,8% y los fungibles, cuando fueron necesarios, desde los hospitales para el 53,8%. La NED se suspendió en 1.031 pacientes (34,1%) durante el periodo de estudio, 56,6% debido a fallecimiento y 22,2% debido a recuperación de la vía oral. Conclusiones: Los datos del registro NADYA-SENPE deben ser interpretados con precaución ya que se trata de un registro voluntario. A pesar del cambio de metodología del registro en 2010, las tendencias en NED se han mantenido, salvo la importancia cuantitativa de la vía ora

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Charge and Zener polaron order in Bi0.75Sr0.25MnO3

We have characterized the RT structure of Bi0.75Sr0.25MnO3 by means of electron diffraction, synchrotron x-ray, and neutron powder diffraction. These data evidence that a;b;A2ap and c;2ap average structure presents a modulation that doubles the a and c lattice parameters. The temperature evolution of this compound above RT has been investigated using magnetization, calorimetry measurements, and neutron powder diffraction. These data reveal that the superstructure disappears above ;575 K where a structural transition takes place. Susceptibility data show that, concomitant to the formation of the superstructure ~on cooling!, there is an enhancement of the effective paramagnetic moment as has also been found in other Bi-(Sr,Ca)MnO3 bismuth manganites. The observed features and cell evolution signals that a new type of charge and polaron ordering occurs at this composition

Budget impact analysis of bevacizumab biosimilars

Data de publicació electrònica: 22-12-2021Objective: to assess the economic impact of introducing biosimilars of bevacizumab for the management of cancer patients receiving systemic bevacizumab in the National Health System (SNHS) of Spain. Methods: a 3-year budget impact analysis model was adapted to estimate the cost of introducing biosimilars of bevacizumab in the SNHS for the adult population who were candidates to receive treatment with bevacizumab. Values for the estimation of the population were obtained from the literature and were validated by an expert panel. In this analysis only pharmaceutical costs (€, year 2021) obtained from official databases were considered. A sensitivity analysis was performed to examine the robustness of the model. Results: the introduction of bevacizumab biosimilars would generate an annual cost saving of €11 558 268 (-5.1%) for the first year with a penetration share of biosimilars from 30.0%, €29 126 373 (-8.5%) for the second year with a share of 50.0% and €52 361 778 (-13.6%) for the third year with a share of 80.0%. The total pharmaceutical costs of the scenario without biosimilars are €227 033 352 for the first year, €342 663 209 for the second year and €385 013 076 for the third year. In contrast, the pharmaceutical costs of the scenario with bevacizumab biosimilars are €215 475 084, €313 536 836 and €332 651 297 for years 1, 2 and 3, respectively. Conclusions: the introduction of biosimilars in the Spanish Health System would generate saving costs in the pharmacological budget to boost biological drugs from the first year

Charge and Zener polaron order in Bi0.75Sr0.25MnO3

We have characterized the RT structure of Bi0.75Sr0.25MnO3 by means of electron diffraction, synchrotron x-ray, and neutron powder diffraction. These data evidence that a;b;A2ap and c;2ap average structure presents a modulation that doubles the a and c lattice parameters. The temperature evolution of this compound above RT has been investigated using magnetization, calorimetry measurements, and neutron powder diffraction. These data reveal that the superstructure disappears above ;575 K where a structural transition takes place. Susceptibility data show that, concomitant to the formation of the superstructure ~on cooling!, there is an enhancement of the effective paramagnetic moment as has also been found in other Bi-(Sr,Ca)MnO3 bismuth manganites. The observed features and cell evolution signals that a new type of charge and polaron ordering occurs at this composition

A home enteral nutrition (HEN); spanish registry of NADYA-SENPE group; for the year 2013.

AIM: To present the results of the Spanish home enteral nutrition (HEN) registry of the NADYA-SENPE group for the year 2013. MATERIAL AND METHODS: From January 1st to December 31st 2013 data was recorded for the HEN registry and further descriptive and analytical analysis was done. RESULTS: In this period 3 223 patients (50.6% men) and a total of 3 272 episodes of HEN were registered in 33 Spanish hospitals. The rate of prevalence was of 67,11 patients/million habitants/ year 2013. A high percentage of patients (98,24%) were older than 14 years. Adult's mean age was 69,14 years (sd 17,64) and men were younger than women p-value <0,001. Children mean age was 2,38 years (sd 4,35). The most frequent indication for HEN was neurological disease for children (49,1%). and for adults (60,6%). Gastrostomy was the most used administration route for children (51%) while younger ones were fed with NGT (p-value 0,003) also older adults (48%) were fed with this type of tube (p-value <0,001). The most frequent reasons for cessation of treatment was death, 44,4% were children and 54,7% were adults. CONCLUSIONS: The number of patients and hospitals registered increased in the last years while the other variables maintain steady. The registry developed allowing contrasted analysis of data in order to get more informationYesObjetivo: exponer los resultados del registro de nutrición enteral domiciliaria (NED) del año 2013 del Grupo NADYA-SENPE. Material y métodos: se recopilaron los pacientes introducidos en el registro desde el 1 de enero al 31 de diciembre de 2013, procediendo al análisis descriptivo y analítico de los datos. Resultados: durante este periodo se registraron 3.223 pacientes, (50,6% varones) y un total de 3.272 episodios de NED en 33 hospitales españoles. La tasa de prevalencia fue de 67,11pacientes/millón de habitantes/año 2013. El 98,24% de los enfermos tenía más de 14 años. La media de edad de los adultos fue de 69,14 años (dt 17,64) y la mediana se situó en 73 años (IIQ 58-83), siendo los varones más jóvenes que las mujeres; p-valor < 0,001. Los niños tuvieron una edad media de 2,38 años (dt 4,35). La enfermedad que con más frecuencia motivó el uso de la NED fue la patología neurológica en niños (49,1%) y en adultos (60,6%). La vía de administración más utilizada en los niños fue la gastrostomía (51%), siendo los niños más pequeños los que se alimentaban por SNG (p-valor 0,003) y en los adultos (48%), siendo estos pacientes los de mayor edad (p-valo

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research