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1.
Bull Am Meteorol Soc ; 100(1): 155-171, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33005057

RESUMO

The ozonesonde is a small balloon-borne instrument that is attached to a standard radiosonde to measure profiles of ozone from the surface to 35 km with ~100-m vertical resolution. Ozonesonde data constitute a mainstay of satellite calibration and are used for climatologies and analysis of trends, especially in the lower stratosphere where satellites are most uncertain. The electrochemical-concentration cell (ECC) ozonesonde has been deployed at ~100 stations worldwide since the 1960s, with changes over time in manufacture and procedures, including details of the cell chemical solution and data processing. As a consequence, there are biases among different stations and discontinuities in profile time-series from individual site records. For 22 years the Jülich [Germany] Ozone Sonde Intercomparison Experiment (JOSIE) has periodically tested ozonesondes in a simulation chamber designated the World Calibration Centre for Ozonesondes (WCCOS) by WMO. In October-November 2017 a JOSIE campaign evaluated the sondes and procedures used in SHADOZ (Southern Hemisphere Additional Ozonesondes), a 14-station sonde network operating in the tropics and subtropics. A distinctive feature of the 2017 JOSIE was that the tests were conducted by operators from eight SHADOZ stations. Experimental protocols for the SHADOZ sonde configurations, which represent most of those in use today, are described, along with preliminary results. SHADOZ stations that follow WMO-recommended protocols record total ozone within 3% of the JOSIE reference instrument. These results and prior JOSIEs demonstrate that regular testing is essential to maintain best practices in ozonesonde operations and to ensure high-quality data for the satellite and ozone assessment communities.

2.
Ginecol. obstet. Méx ; 90(9): 756-768, ene. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1430437

RESUMO

Resumen OBJETIVO: Emitir recomendaciones para la vigilancia y seguimiento de pacientes embarazadas con diabetes mellitus tipos 1, 2 y gestacional con base en la experiencia de un grupo de especialistas y en lo reportado en la bibliografía, desde la perspectiva del sistema de salud mexicano. MATERIALES Y MÉTODOS: Se utilizó la metodología del panel Delphi modificado, mediante la unanimidad de criterios de un grupo de especialistas en Ginecoobstetricia, Biología de la Reproducción y Medicina Materno Fetal mexicanos, tomando en cuenta un nivel de unanimidad del 80% de los participantes. RESULTADOS: Con base en un ejercicio de consenso se recomienda el monitoreo continuo de la glucosa en todas las pacientes embarazadas con diabetes mellitus tipos 1 y 2 a partir del primer trimestre de la gestación. En pacientes con diabetes gestacional considerar, a partir del segundo o tercer trimestre, el monitoreo continuo de la glucosa en usuarias de insulina o en descontrol glucémico, dependiendo del momento en que se diagnostique la diabetes gestacional, del descontrol glucémico y de la necesidad de insulina. La hemoglobina glucosilada y el tiempo en las concentraciones límite también son métricas de control glucémico. CONCLUSIONES: El monitoreo continuo de la glucosa tiene ventajas en: menos complicaciones perinatales, detección oportuna y reducción de eventos de hiper o hipoglucemia, menor descontrol, ajuste de dosis respecto del tratamiento con insulina y mejora en los hábitos para controlar las concentraciones de glucosa.


Abstract OBJECTIVE: To issue recommendations for the surveillance and follow-up of pregnant patients with types 1, 2 and gestational diabetes mellitus based on the experience of a group of experts and on what is reported in the literature, from the perspective of the Mexican health system. MATERIALS AND METHODS: A modified Delphi Panel methodology was performed, through consensus among gynecology, reproductive biologist, and fetal-maternal specialists, and an 80% consensus of all participants. RESULTS: Based on the consensus exercise, we recommend continuous glucose monitoring in all pregnant patients with type I and II diabetes starting on the first trimester; meanwhile in patients with gestational diabetes, continuous monitoring should be considered in patients treated with insulin or uncontrolled glycemia, starting in the second or third trimester, depending on the moment of diagnosis, glycemic levels and insulin requirements, taking into account HbA1c levels and time in range as well as glycemic control metrics. CONCLUSIONS: Continuous glucose monitoring has advantages including the reduction of perinatal complications, timely detection, reduction in the number of hyper/hypoglycemia events, fewer uncontrolled patients, and the capacity for insulin dosage adjustments and improvement of habits for glucose control.

3.
J. health med. sci. (Print) ; 7(4): 231-238, oct.-dic. 2021. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-1391707

RESUMO

To ensure a reliable verification of a radiation detector, the right parameters for this response verification must be determined and a specific characterization on the detectors of interest must be performed. These were the main pillars of this study, where four Geiger-Müller at the University of Costa Rica's Cyclotron Facilities' main laboratories were studied and characterized using a 137Cs source. First, a verification of the inverse-square law was performed to corroborate the correct measurement by the detectors as the distance from a 137Cs source to the detectors was varied using a new design for a positioner support to ensure repeatability. This verification yielded a potential fit curve with and equation D=670635 x-1.961 (error percentage of 1.95%) and an R2 value of 0.9836. Then, using combinations of copper plates of widths 1.0 mm and 2.0 mm as attenuators between the source and the detectors, the mass attenuation coefficient for copper was obtained only as a reference value for future calibrations of the detectors. The result for this value was 0.040 cm2 /g. The results obtained in this study and the method developed to achieve these results will serve as a base for calibrations of the detectors at these facilities, which will ensure the safety of the patients and personnel in this building.


Para asegurar respuesta correcta de un detector de radiación, se deben determinar los parámetros correctos para esta verificación y debe realizarse una caracterización específica de los detectores de interés. Estos fueron los pilares principales de este estudio, donde se estudiaron y caracterizaron 4 detectores Geiger-Müller en los laboratorios principales del Ciclotrón de la Universidad de Costa Rica utilizando una fuente radiactiva de 137Cs. Primero, se realizó una verificación de la ley del inverso-cuadrado para corroborar la medición correcta de los detectores según se varía la distancia entre la fuente de 137Cs al detector utilizando un diseño nuevo de un soporte posicionador para la fuente que asegura la repetibilidad entre experimentos. Esta verificación resultó en una curva de ajuste potencial de ecuación D=670635x-1,961 (porcentaje de error de 1,95%) y un valor de R2 de 0,9836. Luego, utilizando combinaciones de placas de cobre de espesores 1,0 mm y 2,0 mm como atenuadores entre la fuente y los detectores, se obtuvo el coeficiente de atenuación másico para el cobre como un valor de referencia para futuras calibraciones de los detectores. Este resultado fue de 0,040 cm2/g. Los resultados obtenidos en esta investigación y el método desarrollado para lograr estos resultados servirán como una base para una futura confirmación metrológica calibraciones de los detectores en estos laboratorios, lo cual colaborará con la seguridad y protección radiológica de pacientes y trabajadores en este edificio.


Assuntos
Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Radiometria/instrumentação , Radiometria/métodos , Universidades , Calibragem , Radioisótopos de Césio , Ciclotrons , Exposição à Radiação/análise , Exposição à Radiação/prevenção & controle , Costa Rica
4.
J Am Soc Mass Spectrom ; 26(2): 292-304, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25588720

RESUMO

Technology advances in the field of small, unmanned aerial vehicles and their integration with a variety of sensor packages and instruments, such as miniature mass spectrometers, have enhanced the possibilities and applications of what are now called unmanned aerial systems (UAS). With such technology, in situ and proximal remote sensing measurements of volcanic plumes are now possible without risking the lives of scientists and personnel in charge of close monitoring of volcanic activity. These methods provide unprecedented, and otherwise unobtainable, data very close in space and time to eruptions, to better understand the role of gas volatiles in magma and subsequent eruption products. Small mass spectrometers, together with the world's smallest turbo molecular pump, have being integrated into NASA and University of Costa Rica UAS platforms to be field-tested for in situ volcanic plume analysis, and in support of the calibration and validation of satellite-based remote sensing data. These new UAS-MS systems are combined with existing UAS flight-tested payloads and assets, such as temperature, pressure, relative humidity, SO2, H2S, CO2, GPS sensors, on-board data storage, and telemetry. Such payloads are capable of generating real time 3D concentration maps of the Turrialba volcano active plume in Costa Rica, while remote sensing data are simultaneously collected from the ASTER and OMI space-borne instruments for comparison. The primary goal is to improve the understanding of the chemical and physical properties of emissions for mitigation of local volcanic hazards, for the validation of species detection and abundance of retrievals based on remote sensing, and to validate transport models.

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