297 research outputs found

    Distribución de subtipos moleculares de adenocarcinoma de pulmón y resultados clínicos en un centro de Argentina

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    La prevalencia de alteraciones en oncogenes en adenocarcinoma de pulmón varía en nuestra región. El objetivo fue describir la prevalencia de mutaciones en KRAS, BRAF y EGFR y las translocaciones de ALK en pacientes con adenocarcinoma de pulmón y estudiar la supervivencia de acuerdo a subtipos moleculares. Se incluyeron pacientes con biopsias adecuadas para el estudio. Se evaluó el estado mutacional de KRAS, BRAF y EGFR por secuenciación con la técnica de Sanger. Las translocaciones de ALK se estudiaron por hibridación in situ por fluorescencia (FISH) e inmunohistoquimica (IHQ) contra ALK (clones D5F3 y 5A4). De 118 pacientes evaluados, se incluyeron 84 (72%) con análisis molecular completo. Se detectaron mutaciones de KRAS en 16 muestras (19%), EGFR en 11 (13%), y BRAF en 1 muestra (1%). Se detectaron rearreglos de ALK en 3 muestras (4%). La mediana de seguimiento de los pacientes fue de 42.4 [rango intercuatilo (RIC): 27.0-64.2] meses. Globalmente, la mediana de supervivencia en la población fue 10.3 [RIC: 5.6-20.2] meses y fue de 10.8 [RIC: 6.0 20.3] meses en pacientes sin alteraciones moleculares detectables. La mediana de supervivencia de los pacientes con mutación en KRAS fue de 9.6 [RIC: 3.7-16.1] meses (HR: 1.08; p = 0.82) y 32.5 [RIC: 19.6-38.4] meses en el grupo con rearreglos de ALK o mutaciones en EGFR tratados con inhibidores de tirosina quinasa (HR: 0.27; p = 0.03). En conclusión, la prevalencia de alteraciones moleculares en nuestra población fue similar a otros países occidentales.The prevalence of relevant oncogenic drivers in lung adenocarcinoma varies in our region and data on clinical outcomes is scarce. The objective of the study was to describe the prevalence of KRAS, BRAF and EGFR mutations and ALK translocations in patients with advanced lung adenocarcinoma, and to depict the clinical outcome according to treatment strategies. Patients with adequate tumor biopsy sampling were included. KRAS, BRAF and EGFR mutations were studied by Sanger sequencing. ALK translocations were studied by fluorescent in situ hybridization (FISH) and immunohistochemistry (IH) with antibodies against ALK with clones D5F3 and 5A4. Informed consent was signed by 118 patients and 84 (72%) with complete molecular analysis were included. KRAS mutations were detected in 16 samples (19%), EGFR in 11 (13%), 9 of them conferring sensitivity to EGFR inhibitors, and BRAF mutations in 1 (1%). ALK translocations were detected in 3 samples (4%). Median follow-up was 42.4 [interquartile range (IQR): 27.0-64.2] months. Globally, median overall survival was 10.3 [IQR: 5.6-20.2] months. Median survival was 10.8 [IQR: 6.0-20.3] months in the group of patients without detectable molecular alteration, 9.6 [IQR: 3.7-16.1] months in KRAS mutant population (HR: 1.08; p = 0.82) and 32.5 [IQR: 19.6-38.4] months in patients with ALK translocations or sensitizing EGFR mutated tumors treated with tyrosine kinase inhibitors (HR: 0.27; p = 0.03). In conclusion, the prevalence of molecular alterations and outcomes in our population is similar to that reported in other studies in Western countries.Fil: Recondo, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Denninghoff, Valeria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Cuello, Maria T.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Lorente, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Greco, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: de la Vega, Máximo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Avagnina, Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Recondo, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; Argentin

    Correlation between PD-L1 expression (clones 28-8 and SP263) and histopathology in lung adenocarcinoma

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    Lung cancer is the leading cause of cancer-related death worldwide. Recent advances in the management of non-small cell carcinoma are focused on the discovery of targeted therapies and novel immunotherapy strategies for patients with advanced disease. Treatment with anti PD-(L)1 immune checkpoint inhibitors requires the development of predictive biomarkers to select those patients that can most benefit from these therapies. Several immunohistochemical biomarkers have been developed in different technological platforms. However, the most useful and accessible for the daily clinical practice need to be selected. The objective of this study was to compare PD-L1 expression by automated immunohistochemistry in lung adenocarcinoma (ADC) FFPE samples with clones 28-8 and SP263 performed with the BenchMark GX automated staining instrument. To further determine interobserver agreement between two pathologists, and to correlate the results with histologic and pathology variables. FFPE tissue from 40 samples obtained from patients with lung ADC were reviewed retrospectively. Among all studied specimens, 53% of samples presented <1% of positive tumor cells with the 28-8 clone and 50% had <1% of PD-L1 expression in tumor cells with the SP263 clone; PD-L1 expression between ≥1 and <5% was observed in 18% and 24%; ≥5 and <50% PD-L1 expression in 18% and 21%; and ≥50% PD-L1 expression in 11% and 5% of samples, respectively. Similar results between antibodies were observed in 84% of cases for each of the four PD-L1 cutoff groups (Pearson's score 0.90, p < 0.00001). The interobserver degree of agreement calculated with Kappa was 0.75 (95%CI: 0.57–0.93), z = 7.08; p < 0.001. Lepidic, acinar and mucinous patterns had predominantly <1% PD-L1 expression, and the solid pattern subtype had high levels of PD-L1 staining using both clones. PD-L1 expression in less than 1% of tumor cells was similar in stages I/II compared to III/IV. No significant differences were observed in PD-L1 staining and quantification pattern between IHC antibodies 28-8 and SP263.Fil: García, Alejandro. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Recondo, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Greco, Martín. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: de la Vega, Máximo. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Perazzo, Florencia. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Avagnina, Alejandra. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Denninghoff, Valeria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; Argentin

    Empirical models for estimating air temperature using MODIS Land Surface Temperature (and Spatiotemporal Variables) in the Hurd Peninsula of Livingston Island, Antarctica, between 2000 and 2016

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    In this article, we present empirical models for estimating daily mean air temperature (Ta) in the Hurd Peninsula of Livingston Island (Antarctica) using Moderate Resolution Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) data and spatiotemporal variables. The models were obtained and validated using the daily mean Ta from three Spanish in situ meteorological stations (AEMET stations), Juan Carlos I (JCI), Johnsons Glacier (JG), and Hurd Glacier (HG), and three stations in our team’s monitoring sites, Incinerador (INC), Reina Sofía (SOF), and Collado Ramos (CR), as well as daytime and nighttime Terra-MODIS LST and Aqua-MODIS LST data between 2000 and 2016. Two types of multiple linear regression (MLR) models were obtained: models for each individual station (for JCI, INC, SOF, and CR—not for JG and HG due to a lack of data) and global models using all stations. In the study period, the JCI and INC stations were relocated, so we analyzed the data from both locations separately (JCI1 and JCI2; INC1 and INC2). In general, the best individual Ta models were obtained using daytime Terra LST data, the best results for CR being followed by JCI2, SOF, and INC2 (R2 = 0.5–0.7 and RSE = 2 °C). Model cross validation (CV) yielded results similar to those of the models (for the daytime Terra LST data: R2CV = 0.4–0.6, RMSECV = 2.5–2.7 °C, and bias = −0.1 to 0.1 °C). The best global Ta model was also obtained using daytime Terra LST data (R2 = 0.6 and RSE = 2 °C; in its validation: R2CV = 0.5, RMSECV = 3, and bias = −0.03), along with the significant (p < 0.05) variables: linear time (t) and two time harmonics (sine-cosine), distance to the coast (d), slope (s), curvature (c), and hour of LST observation (H). Ta and LST data were carefully corrected and filtered, respectively, prior to its analysis and comparison. The analysis of the Ta time series revealed different cooling/warming trends in the locations, indicating a complex climatic variability at a spatial scale in the Hurd Peninsula. The variation of Ta in each station was obtained by the Locally Weighted Regression (LOESS) method. LST data that was not “good quality” usually underestimated Ta and were filtered, which drastically reduced the LST data (<5% of the studied days). Despite the shortage of “good” MODIS LST data in these cold environments, all months were represented in the final dataset, demonstrating that the MODIS LST data, through the models obtained in this article, are useful for estimating long-term trends in Ta and generating mean Ta maps at a global level (1 km2 spatial resolution) in the Hurd Peninsula of Livingston Island

    Prediction of topsoil organic carbon using airborne and satellite hyperspectral imagery

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    The Airborne Hyperspectral Scanner (AHS) and the Hyperion satellite hyperspectral sensors were evaluated for their ability to predict topsoil organic carbon (C) in burned mountain areas of northwestern Spain slightly covered by heather vegetation. Predictive models that estimated total organic C (TOC) and oxidizable organic C (OC) content were calibrated using two datasets: a ground observation dataset with 39 topsoil samples collected in the field (for models built using AHS data), and a dataset with 200 TOC/OC observations predicted by AHS (for models built using Hyperion data). For both datasets, the prediction was performed by stepwise multiple linear regression (SMLR) using reflectances and spectral indices (SI) obtained from the images, and by the widely-used partial least squares regression (PLSR) method. SMLR provided a performance comparable to or even better than PLSR, while using a lower number of channels. SMLR models for the AHS were based on a maximum of eight indices, and showed a coefficient of determination in the leave-one-out cross-validation R2 = 0.60–0.62, while models for the Hyperion sensor showed R2 = 0.49–0.61, using a maximum of 20 indices. Although slightly worse models were obtained for the Hyperion sensor, which was attributed to its lower signal-to-noise ratio (SNR), the prediction of TOC/OC was consistent across both sensors. The relevant wavelengths for TOC/OC predictions were the red region of the spectrum (600–700 nm), and the short wave infrared region between ~2000–2250 nm. The use of SMLR and spectral indices based on reference channels at ~1000 nm was suitable to quantify topsoil C, and provided an alternative to the more complex PLSR method

    Frozen ground and snow cover monitoring in Livingston and Deception islands, Antarctica: preliminary results of the 2015-2019 PERMASNOW project

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    Since 2006, our research team has been establishing in the islands of Livingston and Deception, (South Shetland archipelago, Antarctica) several monitoring stations of the active layer thickness within the international network Circumpolar Active Layer Monitoring (CALM), and the ground thermal regime for the Ground Terrestrial Network-Permafrost (GTN-P). Both networks were developed within the International Permafrost Association (IPA). In the GTN-P stations, in addition to the temperature of the air, soil, and terrain at different depths, the snow thickness is also monitored by snow poles. Since 2006, a delay in the disappearance of the snow layer has been observed, which could explain the variations we observed in the active layer thickness and permafrost temperatures. Therefore, in late 2015 our research group started the PERMASNOW project (2015-2019) to pay attention to the effect of snow cover on ground thermal This project had two different ways to study the snow cover. On the first hand, in early 2017 we deployed new instrumentation, including new time lapse cameras, snow poles with high number of sensors and a complete and complex set of instruments and sensors to configure a snow pack analyzer station providing 32 environmental and snow parameters. We used the data acquired along 2017 and 2018 years with the new instruments, together with the available from all our already existing sensors, to study in detail the snow cover. On the other hand, remote sensing data were used to try to map the snow cover, not only at our monitoring stations but the entire islands in order to map and study the snow cover distribution, as well as to start the way for future permafrost mapping in the entire islands. MODIS-derived surface temperatures and albedo products were used to detect the snow cover and to test the surface temperature. Since cloud presence limited the acquisition of valid observations of MODIS sensor, we also analyzed Terrasar X data to overcome this limitation. Remote sensing data validation required the acquirement of in situ ground-true data, consisting on data from our permanent instruments, as well as ad hoc measurements in the field (snow cover mapping, snow pits, albedo characterization, etc.). Although the project is finished, the data analysis is still ongoing. We present here the different research tasks we are developing as well as the most important results we already obtained about the snow cover. These results confirm how the snow cover duration has been changing in the last years, affecting the ground thermal behavior.info:eu-repo/semantics/publishedVersio

    Access of patients with breast and lung cancer to chemotherapy treatment in public and private hospitals in the city of Buenos Aires

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    Objectives: Describe the time elapsed from the diagnosis to treatment with chemotherapy for patients with breast and lung cancer at public and private hospitals in Buenos Aires. Design: Retrospective cohort study. Setting: Three public and three private academic hospitals in Buenos Aires. Participants: Patients with breast (n = 168) or lung cancer (n = 100) diagnosis treated with chemotherapy. Main outcomes measures: Clinical and sociodemographic data were collected in a stratified sample. We used the Kaplan–Meier estimator to analyse the time elapsed and the log rank test to compare both groups Results: For breast cancer patients, median time elapsed between diagnosis and treatment with chemotherapy was 76 days (95% CI: 64–86) in public and 60 days (95% CI: 52–65) in private hospitals (P = 0.0001). For adjuvant and neoadjuvant treatments, median time was 130 (95% CI: 109–159) versus 64 (95% CI: 56–73) days (P < 0.0001) and 57 days (95% CI: 49–75) versus 26 (95% CI: 16–41) days, respectively (P = 0.0002). There were no significant differences in the time from first consultation to diagnosis. In patients with lung cancer, median time from diagnosis to treatment was 71 days (95% CI: 60–83) in public hospitals and 31 days (95% CI: 24–39) in private hospitals (P = 0.0002). In the metastatic setting, median time to treatment was 63 days (95% CI: 45–83) in public and 33 (95% CI: 26–44) days in private hospitals (P = 0.005). Conclusions: There are significant disparity in the access to treatment with chemotherapy for patients in Buenos Aires, Argentina.Fil: Recondo, Gonzalo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Cosacow, César. Centro de Educación Medica E Invest.clinicas; ArgentinaFil: Cutuli, Hernán Javier. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Cermignani, Luciano. Hospital Alemán; ArgentinaFil: Straminsky, Samanta. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; ArgentinaFil: Naveira, Martin. Hospital Británico de Buenos Aires; ArgentinaFil: Pitzzu, Martin. Gobierno de la Ciudad Autónoma de Buenos Aires. Hospital General de Agudos Carlos Durand; ArgentinaFil: De Ronato, Gabriela. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; ArgentinaFil: Nacuzzi, Gabriela. Gobierno de la Ciudad Autónoma de Buenos Aires. Hospital General de Agudos Carlos Durand; ArgentinaFil: Taetti, Gonzalo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Corsico, Santiago. Hospital Británico de Buenos Aires; ArgentinaFil: Berrueta, Mabel. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Colucci, Giuliana. Centro de Educación Medica E Invest.clinicas; ArgentinaFil: Gibbons, Luz. Centro de Educación Medica E Invest.clinicas; ArgentinaFil: Gutierrez, Laura. Centro de Educación Medica E Invest.clinicas; ArgentinaFil: García Elorrio, Ezequiel. Centro de Educación Medica E Invest.clinicas; Argentin

    Comparison of MODIS-derived land surface temperatures with in situ temperatures measured in the Hurd Peninsula, Livingston Island, Antarctica: first results

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    Ponencia presentada en: XVII Congreso de la Asociación Española de Teledetección celebrado en Murcia, del 3 al 7 de octubre de 2017.[ES]En el marco del proyecto PERMASNOW estamos comparando los datos térmicos MODIS (LST, 1-km) con los obtenidos in situ (Ta y Ts) en las estaciones meteorológicas de la AEMET y las propias del proyecto en la península Hurd, isla Livingston (Antártida). Este trabajo muestra los primeros resultados obtenidos para las estaciones de la AEMET: Juan Carlos I (JCI), Glaciar Johnson (GJ) y Glaciar Hurd (GH) en el periodo marzo-2000/julio-2002 y febrero-2016. Se comparan los datos diarios LST con los valores medios diarios de Ta y Ts. Se observa una alta correlación lineal entre Ta y Ts, restringiéndose entonces la comparación a Ta. Se confirma también la tendencia lineal ligeramente decreciente de Ta en el periodo estudiado. Aunque la nubosidad limita la disponibilidad de datos LST, sin embargo, el mayor problema proviene de la calidad de los datos LST, observando que los que no son de “good quality” generalmente subestiman mucho LST y no son fiables. El producto MODIS-albedo diario (500-m) nos ayuda a mejorar el filtrado de datos de “other quality” y “cloud”, además de clasificar la cubierta en tierra (con/sin nieve) o agua (nieve/hielo fundido). El filtrado reduce a un 3-8% los días con datos disponibles en JCI y GJ y elimina todos en GH. Un ajuste lineal simple no explica bien la relación LST (tierra/agua)-Ta (R2=0,1-0,4), recurriendo a regresiones lineales múltiples para tener en cuenta las variaciones anuales/estacionales en esta relación. Así R2 sube a 0,3-0,6, siendo mejor en JCI (R2=0,6 y RSE~2°C). Se concluye que los datos LST-MODIS sirven para estimar tendencias a largo plazo en Ta a nivel global en la isla Livingston. Mejorar la calidad de los datos LST en este tipo de ambientes fríos es esencial.[EN]In the framework of the PERMASNOW project, we are comparing the MODIS thermal data (LST, 1-km) with those obtained in situ (Ta and Ts) at the AEMET meteorological stations and the project’s stations in the Hurd Peninsula, Livingston Island (Antarctica). This article shows the first results obtained at the AEMET stations: Juan Carlos I (JCI), Glacier Johnson (GJ) and Glacier Hurd (GH) in the period of March-2000/July-2002 and February-2016. The daily LST data are compared with the daily mean values of Ta and Ts. A high linear correlation between Ta and Ts is observed, and thus, the comparison being restricted to Ta. The slightly decreasing linear trend of Ta in the studied period is also confirmed. Although the cloudiness limits the availability of LST data, however, the main problem proceeds from the quality of the LST data, observing that those with no “good quality” usually underestimate LST and are not reliable. The daily MODIS albedo product (500-m) helps us to improve the filtering of data with “other quality” and “cloud”, besides of classifying the cover in land (with/without snow) or water (melting snow/ice). The filtering reduces to 3-8% the days with available data at JCI and GJ, and eliminates all of them in GH. A simple linear fit does not explain well the relationship LST (land/water)-Ta (R2=0.1-0.4), appealing to multiple linear regressions to take into account the annual/seasonal variations in this relationship. So, R2 goes up to 0.3-0.6, being better at JCI (R2=0.6 and RSE~2°C). It is concluded that the MODIS-LST data are useful for estimating long-term trends in Ta at a global level in the Livingston Island. Improving the quality of the LST data in this type of cold environments is essential.Este trabajo ha sido financiado por el Ministerio de Economía y Competitividad (MINECO), a través del proyecto PERMASNOW (CTM2014-52021-R)

    Variability of the air temperature and its comparison with MODIS Land Surface Temperature in the Hurd Peninsula of the Livingston Island, Antarctica, between 2000 and 2016

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    Ponencia presentada en: XVIII Congreso de la Asociación Española de Teledetección celebrado en Valladolid del 24 al 27 septiembre 2019.[ES]En los ambientes polares, tan vulnerables al cambio climático, el estudio de la temperatura es imprescindible. Por ello, y en el marco del proyecto PERMASNOW, en este trabajo hemos estudiado en detalle la variación de la temperatura del aire (Ta) en la península Hurd de la isla Livingston (Antártida) y hemos tratado de estimarla a partir de los datos de temperatura de la superficie terrestre (LST, por sus siglas en inglés) del sensor MODIS entre los años 2000 y 2016. Utilizamos datos de Ta media diaria obtenidos en seis puntos, tres estaciones meteorológicas de AEMET y tres estaciones del proyecto PERMASNOW: Juan Carlos I (JCI), Glaciar Johnson (GJ), Glaciar Hurd (GH), Incinerador (INC), Reina Sofía (RS) y Collado Ramos (CR), respectivamente. Los datos MODIS LST son los diurnos y nocturnos de los satélites Terra y Aqua. La tendencia en Ta se ha analizado mediante la regresión localmente ponderada (LOESS, por sus siglas en inglés) y la relación Ta -LST con regresiones lineales múltiples. Concluimos que Ta en el área de estudio varía: se observa en la estación JCI, más cercana a la costa, una tendencia al enfriamiento con valores entre –2,3 y –3,0°C década–1. En cambio, las estaciones más alejadas de la costa y de mayor altitud muestran una tendencia al calentamiento (entre +0,2 y +0,8°C década-1). Los mejores modelos de estimación de Ta a partir de LST y variables temporales se obtienen con los datos diurnos de Terra (R2 = 0,5-0,7; RSE = 2°C), exceptuando GJ, donde la variable LST no es significativa. Con la validación cruzada (CV) se aprecian también, excepto en GJ, mejores resultados con los datos diurnos de Terra (R2 CV = 0,5-0,6; RMSECV = 2,5-2,6°C). Finalmente, concluimos que los datos MODIS LST son útiles para estimar tendencias de Ta a largo plazo en el área de estudio.[EN]In polar zones, where satellite data are very useful due to the limited in situ data, it is therefore essential to study the air temperature behaviour. In the framework of the PERMASNOW project we estimated the air temperature (Ta) in the Hurd Peninsula of Livingston Island (Antarctica) from the land surface temperature (LST) data of the MODIS between 2000 and 2016. We worked with Ta data obtained at six stations (3 AEMET meteorological stations and 3 PERMASNOW project stations: Juan Carlos I (JCI), Johnson Glacier (JG), Hurd Glacier (HG), Incinerator (INC), Reina Sofia (RS) and Collado Ramos (CR), respectively. In addition, we analyzed daytime and nighttime LST data from the Terra and Aqua satellites. Locally weighted regression (LOESS) and multiple linear regressions were used for statistical analysis. We conclude that the Ta in the study area varies: a cooling trend with values between –2.3 and –3.0°C decade-1 is observed in JCI, which is closer to the coast. On the other hand, the stations farther from the coast and at higher altitudes show a warming trend (between +0.2 and +0.8°C decade-1). The best Ta models are obtained with Terra daytime data (R2 = 0.5-0.7 and RSE = 2°C), except JG, where the LST variable is not significant. With cross validation (CV), better results are also seen, except in JG, with the daytime Terra data (R2 CV = 0.5-0.6, RMSECV = 2.5-2.6°C). In summary, MODIS LST data are useful for estimating long-term Ta trends in the study area.Esta investigación fue posible gracias a la financiación de la Agencia Estatal de Investigación a través del proyecto PERMASNOW [CTM2014-52021-R], la ayuda de la Universidad de Oviedo al Grupo de Investigación RSApps en 2018 [PAPI-18-GR-2016-0005] y las ayudas obtenidas por A.C.-P. (“Severo Ochoa” del Gobierno del Principado de Asturias [BP17-151] y “Ayuda Predoctoral” de la Universidad de Oviedo)
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