Search results for "Sentinel"
showing 10 items of 189 documents
Monitoring Subaquatic Vegetation Using Sentinel-2 Imagery in Gallocanta Lake (Aragón, Spain)
2022
Remote sensing allows the study of aquatic vegetation cover in shallow lakes from the different spectral responses of the water as the vegetation grows from the bottom toward the surface. In the case of Gallocanta Lake, its seasonality and shallow depth (less than 2 m) allow us to appreciate the variations in the aquatic vegetation with the apparent color. Six common vegetation indices were tested, and the one with the best response was the so-called NDI45, which uses the normalized ratio between the far red (705 nm) and red (665 nm) bands. Our aims are to show the variations in the surface area covered by vegetation at the bottom of the lagoon, its growth and disappearance when drying occu…
A systematic review on external ear melanoma
2014
Summary Background External ear melanoma accounts for only 1% of all cutaneous melanomas, and data on its optimal management and prognosis are limited. Aim We aim to review the literature on external ear melanoma to guide surgeons in the treatment of this uncommon and peculiar pathology. Materials and methods A systematic review of English language studies on ear melanoma published from 1993 to 2013 was performed using the PubMed electronic database. Data on epidemiology, oncological treatment (tumor resection and regional lymph nodes management), and reconstruction were extrapolated from selected papers. Results The total number of patients was 858 (30 studies). The helix was the most comm…
Estimating crop coefficients and actual evapotranspiration in citrus orchards with sporadic cover weeds based on ground and remote sensing data
2022
AbstractAccurate estimations of actual crop evapotranspiration are of utmost importance to evaluate crop water requirements and to optimize water use efficiency. At this aim, coupling simple agro-hydrological models, such as the well-known FAO-56 model, with remote observations of the land surface could represent an easy-to-use tool to identify biophysical parameters of vegetation, such as the crop coefficient Kc under the actual field conditions and to estimate actual crop evapotranspiration. This paper intends, therefore, to propose an operational procedure to evaluate the spatio-temporal variability of Kc in a citrus orchard characterized by the sporadic presence of ground weeds, based o…
Estimating crop primary productivity with Sentinel-2 and Landsat 8 using machine learning methods trained with radiative transfer simulations
2019
Abstract Satellite remote sensing has been widely used in the last decades for agricultural applications, both for assessing vegetation condition and for subsequent yield prediction. Existing remote sensing-based methods to estimate gross primary productivity (GPP), which is an important variable to indicate crop photosynthetic function and stress, typically rely on empirical or semi-empirical approaches, which tend to over-simplify photosynthetic mechanisms. In this work, we take advantage of all parallel developments in mechanistic photosynthesis modeling and satellite data availability for an advanced monitoring of crop productivity. In particular, we combine process-based modeling with …
Introducing ARTMO's Machine-Learning Classification Algorithms Toolbox: Application to Plant-Type Detection in a Semi-Steppe Iranian Landscape.
2022
Accurate plant-type (PT) detection forms an important basis for sustainable land management maintaining biodiversity and ecosystem services. In this sense, Sentinel-2 satellite images of the Copernicus program offer spatial, spectral, temporal, and radiometric characteristics with great potential for mapping and monitoring PTs. In addition, the selection of a best-performing algorithm needs to be considered for obtaining PT classification as accurate as possible . To date, no freely downloadable toolbox exists that brings the diversity of the latest supervised machine-learning classification algorithms (MLCAs) together into a single intuitive user-friendly graphical user interface (GUI). To…
Calidad de la atención al paciente oncológico: Tiempos asistenciales recomendables entre sospecha clínica y definición del plan terapéutico en cáncer…
2012
Fundamento. Determinar tiempos recomendables para el tratamiento desde la sospecha clínica fundada en los procesos asistenciales de cáncer de mama y colorrectal considerando factibilidad y situación personal del paciente. Método. Estudio cualitativo de búsqueda de consenso entre profesionales. Primero, se revisaron mediante 4 sesiones grupales (N=19), los procesos asistenciales de cáncer de mama y cáncer colorrectal y se fijaron los tiempos deseables de ambos procesos. Segundo, mediante una modificación de la técnica Delphi (N=49), se validó la propuesta de tiempos de atención recomendables para cada proceso asistencial. Resultados. La tasa de respuesta en el estudio Delphi fue del 69% en e…
Experimental Sentinel-2 LAI estimation using parametric, non-parametric and physical retrieval methods – A comparison
2015
Abstract Given the forthcoming availability of Sentinel-2 (S2) images, this paper provides a systematic comparison of retrieval accuracy and processing speed of a multitude of parametric, non-parametric and physically-based retrieval methods using simulated S2 data. An experimental field dataset (SPARC), collected at the agricultural site of Barrax (Spain), was used to evaluate different retrieval methods on their ability to estimate leaf area index (LAI). With regard to parametric methods, all possible band combinations for several two-band and three-band index formulations and a linear regression fitting function have been evaluated. From a set of over ten thousand indices evaluated, the …
Impact of Obesity on Sentinel Lymph Node Mapping in Patients with apparent Early-Stage Endometrial Cancer: The ObeLyX study
2022
Conflicting data exists on the impact of Body Mass Index (BMI) on sentinel lymph-node (SLN) detection. The primary study endpoint was to investigate the impact of obesity on overall detection rate, bilateral mapping, and mapping failure rate of SLN. In addition, we evaluated possible differences in terms of surgical management and "empty-packet dissection" rate among obese and non-obese patients.Multicenter, propensity-matched, retrospective study. Patients with apparent early-stage endometrial cancer were included. Study population was divided into women with BMI/≥ 30 (Group-1 and Group-2). To lower the selection bias, a propensity-matched analysis was performed. Matching was based on hist…
A large multicenter propensity match study of sentinel lymph node biopsy feasibility in endometrioid variants of endometrial cancer
2022
Introduction: Sentinel lymph node (SLN) biopsy algorithm has been routinely applied in all endometrial endometrioid tumors, however, no studies analyzed the feasibility of SLN mapping in endometrioid variants (EV), which included villoglandular, secretory, ciliated cell, mucinous, and squamous differentiation. This study aimed to demonstrate the feasibility of SLN biopsy in EV of EC. Materials and methods: All patients undergoing minimally invasive surgical treatment for early-stage EC were included in the study. Patients were divided into 2 study groups: Group 1 which included patients with EV, and Group 2 which included patients with typical endometrioid histology. A propensity match anal…
Sentinel node mapping in endometrial cancer: Tips and tricks to improve bilateral detection rate. The sentitricks study, a monocentric experience.
2020
Abstract Objective The objective of the study is to show some small tricks for bilateral sentinel lymph node (SLN) uptake in endometrial cancer. Materials and methods Each step of the sentinel lymph node technique was analyzed. The cervix was exposed through the use of vaginal valves and by Martin pliers stapling of the anterior cervical lip. Fifty mg Indocyanine Green (ICG) powder was diluted with 10 ml of physiological solution. The spinal needle was marked at 15 mm with a steri-strip. After 20 min from the administration, in case of no LNS identification, an additional 1 ml in the non-detected side was administered in the superficial cervical area. All cervical injections were made by a …