RÉSUMÉ L'objectif principal de cette recherche est de générer une information pour modéliser ... more RÉSUMÉ L'objectif principal de cette recherche est de générer une information pour modéliser la géomorphologie actuelle et ancienne de la région. Les techniques d'analyse d'images constituent l'un des meilleurs outils pour la cartographie géomorphologique dans la région étant donné que les principales formes de terrain (paléodunes et caractéristiques de drainage) sont peu visibles sur le terrain en raison du faible relief et du couvert herbeux dense. Des images RADARSAT-1 en mode faisceau 2 large ont été fusionnées avec une image Landsat TM. Trois grandes unités géomorphologiques ont été différenciées: la chaîne Tandilia, la frange éolienne (marginale par rapport à la chaîne Tandilia) et la plaine fluvio-éolienne. Les meilleurs résultats ont été obtenus par l'intégration d'images RADARSAT-1 durant les périodes sèches et de l'image Landsat durant les périodes humides, spécialement dans la plaine fluvio-éolienne. La zone correspond à une topographie de relief très plat (pente<1%) caractérisé par des dunes longitudinales et paraboliques silteuses et des cuvettes de déflation et des lunettes associées. Un système de drainage constitué de rigoles sous-parallèles courtes est superposé à la topographie relique. Les formes éoliennes de terrain n'avaient jamais été décelées avant que ces images ne soient analysées grâce au contraste entre la topographie et l'humidité du sol qui apporte une information plus détaillée. Les données Landsat TM ont fourni une information utile sur l'utilisation du sol alors que les formes géomorphologiques ne pouvaient être reconnues que sur les images RADARSAT.
The first stage of the study was centered in the measurement on cartographic material and aerial ... more The first stage of the study was centered in the measurement on cartographic material and aerial photographs of different years. Currently recognizable checkpoints were determined on them, both in the inner zone and along the shoreline, to make measurements between ...
Objetivos: conocer la magnitud del riesgo de padecer diabetes mellitus 2 (DM2) en la población de... more Objetivos: conocer la magnitud del riesgo de padecer diabetes mellitus 2 (DM2) en la población del Municipio de Gral. Pueyrredón que concurre a los Centros Asistenciales de Atención Primaria.Materiales y métodos: estudio observacional para determinar el riesgo de padecer DM2 mediante una entrevista donde se indagaron sobre las ocho preguntas del cuestionario FINDRISC.Resultados: la muestra del estudio estuvo constituida por 2.784 pacientes, el 54% conformada por mujeres. La edad fue agrupada en menos de 45 años el 47,5% (1.323), de 45 a 54 años el 20,9% (582), de 55 a 64 años el 18,3% (510) y más de 64 años el 13,2% (368). El 20% de la población presento una puntuación de la escala de riesgo del cuestionario FINDRISC igual o mayor a 15, alto riesgo a muy alto riesgo de padecer diabetes en los próximos 10 años. El 43,38% presento un IMC >30 y el 25,97% declaro recibir medicación para la hipertensión arterial. El 55,37% refería actividad física baja, el 50,79% no ingería verduras y...
In this study, we analyzed the effect of the alveolar recruitment strategy (ARS) and positive end... more In this study, we analyzed the effect of the alveolar recruitment strategy (ARS) and positive end-expiratory pressure (PEEP) titration on Phase III slope (S(III)) of volumetric capnography (VC) in morbidly obese patients. Eleven anesthetized morbidly obese patients were studied. Lungs were ventilated with tidal volumes of 10 mL x kg(-1), respiratory rates of 12-14 bpm, inspiration:expiration ratio of 1:2, and FIO2 of 0.4. ARS was performed by increasing PEEP in steps of five from 0 end-expiratory pressure to 15 cm H2O. During lung recruitment, plateau pressure was limited to 50 cm H2O whereas tidal volume was increased to the ventilator&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s maximum value of 1400 mL, and PEEP was increased to 20 cm H2O for 2 min. Thereafter, PEEP was reduced in steps of 5 cm H2O, from 15 to 0. VC, arterial blood gases, and lung mechanics data were determined for each PEEP step. S(III) decreased from 0.014 +/- 0.006 to 0.005 +/- 0.005 mm Hg/mL when 0 end-expiratory pressure was compared against 15 cm H2O of PEEP after ARS (15ARS, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). This decrement in S(III) was accompanied by increases in PaO2 (27%, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.002) and compliance (32%, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001), whereas PaCO2 decreased by 8% (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.038) when comparing values before and after ARS. A good prediction of the lung recruitment effect by S(III) was derived from the receiver operating characteristic curve analysis (area under the curve of 0.81, sensitivity of 0.75, and specificity of 0.74; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). The S(III) in VC was useful to detect the optimal level of PEEP after lung recruitment in anesthetized morbidly obese patients.
The aim of the present work was to design a methodology based on video processing to obtain indic... more The aim of the present work was to design a methodology based on video processing to obtain indicators of bacterial population motility that allow the quantitative and qualitative analysis and comparison of the chemotactic phenomenon with different attractants in the agarose-in plug bridge method. Video image sequences were processed applying Shannon's entropy to the intensity time series of each pixel, which conducted to a final pseudo colored image resembling a map of the dynamic bacterial clusters. Processed images could discriminate perfectly between positive and negative attractant responses at different periods of time from the beginning of the assay. An index of spatial and temporal motility was proposed to quantify the bacterial response. With this index, this video processing method allowed obtaining quantitative information of the dynamic changes in space and time from a traditional qualitative assay. We conclude that this computational technique, applied to the tradit...
Thalassas an International Journal of Marine Sciences, 2007
The first stage of the study was centered in the measurement on cartographic material and aerial ... more The first stage of the study was centered in the measurement on cartographic material and aerial photographs of different years. Currently recognizable checkpoints were determined on them, both in the inner zone and along the shoreline, to make measurements between ...
We sought to determine whether the response of pulmonary elimination of CO2 (VCO2) to a sudden in... more We sought to determine whether the response of pulmonary elimination of CO2 (VCO2) to a sudden increase in positive end-expiratory pressure (PEEP) could predict fluid responsiveness and serve as a noninvasive surrogate for cardiac index (CI). Fifty-two patients undergoing cardiovascular surgery were included in this study. By using a constant-flow ventilation mode, we performed a PEEP challenge of 1-minute increase in PEEP from 5 to 10 cm H2O. At PEEP of 5 cm H2O, patients were preloaded with 500 mL IV saline solution after which a second PEEP challenge was performed. Patients in whom fluid administration increased CI by ≥15% from the individual baseline value were defined as volume responders. Beat-by-beat CI was derived from arterial pulse contour analysis, and breath-by-breath VCO2 data were collected during the protocol. The sensitivity and specificity of VCO2 for detecting the fluid responders according to CI was performed by the receiver operating characteristic curves. Twenty-one of 52 patients were identified as fluid responders (40%). The PEEP maneuver before fluid administration decreased CI from 2.65 ± 0.34 to 2.21 ± 0.32 L/min/m (P = 0.0011) and VCO2 from 150 ± 23 to 123 ± 23 mL/min (P = 0.0036) in responders, whereas the changes in CI and VCO2 were not significant in nonresponders. The PEEP challenge after fluid administration induced no significant changes in CI and VCO2, in neither responders nor nonresponders. PEEP-induced decreases in CI and VCO2 before fluid administration were well correlated (r = 0.75, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001) but not thereafter. The area under the receiver operating characteristic curves for a PEEP-induced decrease in ΔCI and ΔVCO2 was 0.99, with a 95% confidence interval from 0.96 to 0.99 for ΔCI and from 0.97 to 0.99 for ΔVCO2. During the PEEP challenge, a decrease in VCO2 by 11% predicted fluid responsiveness with a sensitivity of 0.90 (95% confidence interval, 0.87-0.93) and a specificity of 0.95 (95% confidence interval, 0.92-0.98). PEEP-induced changes in VCO2 predicted fluid responsiveness with accuracy in patients undergoing cardiac surgery.
RÉSUMÉ L'objectif principal de cette recherche est de générer une information pour modéliser ... more RÉSUMÉ L'objectif principal de cette recherche est de générer une information pour modéliser la géomorphologie actuelle et ancienne de la région. Les techniques d'analyse d'images constituent l'un des meilleurs outils pour la cartographie géomorphologique dans la région étant donné que les principales formes de terrain (paléodunes et caractéristiques de drainage) sont peu visibles sur le terrain en raison du faible relief et du couvert herbeux dense. Des images RADARSAT-1 en mode faisceau 2 large ont été fusionnées avec une image Landsat TM. Trois grandes unités géomorphologiques ont été différenciées: la chaîne Tandilia, la frange éolienne (marginale par rapport à la chaîne Tandilia) et la plaine fluvio-éolienne. Les meilleurs résultats ont été obtenus par l'intégration d'images RADARSAT-1 durant les périodes sèches et de l'image Landsat durant les périodes humides, spécialement dans la plaine fluvio-éolienne. La zone correspond à une topographie de relief très plat (pente<1%) caractérisé par des dunes longitudinales et paraboliques silteuses et des cuvettes de déflation et des lunettes associées. Un système de drainage constitué de rigoles sous-parallèles courtes est superposé à la topographie relique. Les formes éoliennes de terrain n'avaient jamais été décelées avant que ces images ne soient analysées grâce au contraste entre la topographie et l'humidité du sol qui apporte une information plus détaillée. Les données Landsat TM ont fourni une information utile sur l'utilisation du sol alors que les formes géomorphologiques ne pouvaient être reconnues que sur les images RADARSAT.
The first stage of the study was centered in the measurement on cartographic material and aerial ... more The first stage of the study was centered in the measurement on cartographic material and aerial photographs of different years. Currently recognizable checkpoints were determined on them, both in the inner zone and along the shoreline, to make measurements between ...
Objetivos: conocer la magnitud del riesgo de padecer diabetes mellitus 2 (DM2) en la población de... more Objetivos: conocer la magnitud del riesgo de padecer diabetes mellitus 2 (DM2) en la población del Municipio de Gral. Pueyrredón que concurre a los Centros Asistenciales de Atención Primaria.Materiales y métodos: estudio observacional para determinar el riesgo de padecer DM2 mediante una entrevista donde se indagaron sobre las ocho preguntas del cuestionario FINDRISC.Resultados: la muestra del estudio estuvo constituida por 2.784 pacientes, el 54% conformada por mujeres. La edad fue agrupada en menos de 45 años el 47,5% (1.323), de 45 a 54 años el 20,9% (582), de 55 a 64 años el 18,3% (510) y más de 64 años el 13,2% (368). El 20% de la población presento una puntuación de la escala de riesgo del cuestionario FINDRISC igual o mayor a 15, alto riesgo a muy alto riesgo de padecer diabetes en los próximos 10 años. El 43,38% presento un IMC >30 y el 25,97% declaro recibir medicación para la hipertensión arterial. El 55,37% refería actividad física baja, el 50,79% no ingería verduras y...
In this study, we analyzed the effect of the alveolar recruitment strategy (ARS) and positive end... more In this study, we analyzed the effect of the alveolar recruitment strategy (ARS) and positive end-expiratory pressure (PEEP) titration on Phase III slope (S(III)) of volumetric capnography (VC) in morbidly obese patients. Eleven anesthetized morbidly obese patients were studied. Lungs were ventilated with tidal volumes of 10 mL x kg(-1), respiratory rates of 12-14 bpm, inspiration:expiration ratio of 1:2, and FIO2 of 0.4. ARS was performed by increasing PEEP in steps of five from 0 end-expiratory pressure to 15 cm H2O. During lung recruitment, plateau pressure was limited to 50 cm H2O whereas tidal volume was increased to the ventilator&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s maximum value of 1400 mL, and PEEP was increased to 20 cm H2O for 2 min. Thereafter, PEEP was reduced in steps of 5 cm H2O, from 15 to 0. VC, arterial blood gases, and lung mechanics data were determined for each PEEP step. S(III) decreased from 0.014 +/- 0.006 to 0.005 +/- 0.005 mm Hg/mL when 0 end-expiratory pressure was compared against 15 cm H2O of PEEP after ARS (15ARS, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). This decrement in S(III) was accompanied by increases in PaO2 (27%, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.002) and compliance (32%, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001), whereas PaCO2 decreased by 8% (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.038) when comparing values before and after ARS. A good prediction of the lung recruitment effect by S(III) was derived from the receiver operating characteristic curve analysis (area under the curve of 0.81, sensitivity of 0.75, and specificity of 0.74; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). The S(III) in VC was useful to detect the optimal level of PEEP after lung recruitment in anesthetized morbidly obese patients.
The aim of the present work was to design a methodology based on video processing to obtain indic... more The aim of the present work was to design a methodology based on video processing to obtain indicators of bacterial population motility that allow the quantitative and qualitative analysis and comparison of the chemotactic phenomenon with different attractants in the agarose-in plug bridge method. Video image sequences were processed applying Shannon's entropy to the intensity time series of each pixel, which conducted to a final pseudo colored image resembling a map of the dynamic bacterial clusters. Processed images could discriminate perfectly between positive and negative attractant responses at different periods of time from the beginning of the assay. An index of spatial and temporal motility was proposed to quantify the bacterial response. With this index, this video processing method allowed obtaining quantitative information of the dynamic changes in space and time from a traditional qualitative assay. We conclude that this computational technique, applied to the tradit...
Thalassas an International Journal of Marine Sciences, 2007
The first stage of the study was centered in the measurement on cartographic material and aerial ... more The first stage of the study was centered in the measurement on cartographic material and aerial photographs of different years. Currently recognizable checkpoints were determined on them, both in the inner zone and along the shoreline, to make measurements between ...
We sought to determine whether the response of pulmonary elimination of CO2 (VCO2) to a sudden in... more We sought to determine whether the response of pulmonary elimination of CO2 (VCO2) to a sudden increase in positive end-expiratory pressure (PEEP) could predict fluid responsiveness and serve as a noninvasive surrogate for cardiac index (CI). Fifty-two patients undergoing cardiovascular surgery were included in this study. By using a constant-flow ventilation mode, we performed a PEEP challenge of 1-minute increase in PEEP from 5 to 10 cm H2O. At PEEP of 5 cm H2O, patients were preloaded with 500 mL IV saline solution after which a second PEEP challenge was performed. Patients in whom fluid administration increased CI by ≥15% from the individual baseline value were defined as volume responders. Beat-by-beat CI was derived from arterial pulse contour analysis, and breath-by-breath VCO2 data were collected during the protocol. The sensitivity and specificity of VCO2 for detecting the fluid responders according to CI was performed by the receiver operating characteristic curves. Twenty-one of 52 patients were identified as fluid responders (40%). The PEEP maneuver before fluid administration decreased CI from 2.65 ± 0.34 to 2.21 ± 0.32 L/min/m (P = 0.0011) and VCO2 from 150 ± 23 to 123 ± 23 mL/min (P = 0.0036) in responders, whereas the changes in CI and VCO2 were not significant in nonresponders. The PEEP challenge after fluid administration induced no significant changes in CI and VCO2, in neither responders nor nonresponders. PEEP-induced decreases in CI and VCO2 before fluid administration were well correlated (r = 0.75, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.0001) but not thereafter. The area under the receiver operating characteristic curves for a PEEP-induced decrease in ΔCI and ΔVCO2 was 0.99, with a 95% confidence interval from 0.96 to 0.99 for ΔCI and from 0.97 to 0.99 for ΔVCO2. During the PEEP challenge, a decrease in VCO2 by 11% predicted fluid responsiveness with a sensitivity of 0.90 (95% confidence interval, 0.87-0.93) and a specificity of 0.95 (95% confidence interval, 0.92-0.98). PEEP-induced changes in VCO2 predicted fluid responsiveness with accuracy in patients undergoing cardiac surgery.
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