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1.
Sci Adv ; 8(26): eabm6185, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35767617

RESUMEN

An accurate record of preindustrial (pre-1900 CE) sea level is necessary to contextualize modern global mean sea level (GMSL) rise with respect to natural variability. Precisely dated phreatic overgrowths on speleothems (POS) provide detailed rates of Late Holocene sea-level rise in Mallorca. Statistical analysis indicates that sea level rose locally by 0.12 to 0.31 m (95% confidence) from 3.26 to 2.84 thousand years (ka) ago (2σ) and remained within 0.08 m (95% confidence) of preindustrial levels from 2.84 ka to 1900 CE. This sea-level history is consistent with glacial isostatic adjustment models adopting relatively weak upper mantle viscosities of ~1020 Pa s. There is virtual certainty (>0.999 probability) that the average GMSL rise since 1900 CE has exceeded even the high average rate of sea-level rise between 3.26 and 2.84 ka inferred from the POS record. We conclude that modern GMSL rise is anomalous relative to any natural variability in ice volumes over the past 4000 years.

3.
Sci Rep ; 11(1): 261, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33479271

RESUMEN

Sea-level reconstructions are important for understanding past ice sheet variability and its response to past and future warming. Here we present Neogene and Quaternary sea-level snapshots using phreatic overgrowths on speleothems (POS) from caves on Mallorca, Spain. POS are excellent sea level index points because of their clear relationship to sea level and precise U-Pb chronology. We find that local sea-level before and at the onset of the Messinian Salinity Crisis was at 33.3 ± 0.25 m (6.54 ± 0.37 Ma) and 31.8 ± 0.25 m (5.86 ± 0.60 Ma) above present levels, respectively. We further present global mean sea level (GMSL) estimates, i.e. local sea level corrected for glacial isostatic adjustment and long-term uplift, for three other POS. The results show that GMSL during the Pliocene-Pleistocene Transition was 6.4 m (- 2.0-8.8 m) at 2.63 ± 0.11 Ma and during the beginning and the end of the Mid-Pleistocene Transition was - 1.1 m (- 5.6-2.4 m) and 5 m (1.5-8.1 m), respectively. These estimates provide important constraints for the past evolution of sea level and show that local sea level prior to the MSC was similar to the highest stand during the Pliocene, with markedly lower position afterwards.

4.
Nature ; 574(7777): 233-236, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31471591

RESUMEN

Reconstructing the evolution of sea level during past warmer epochs such as the Pliocene provides insight into the response of sea level and ice sheets to prolonged warming1. Although estimates of the global mean sea level (GMSL) during this time do exist, they vary by several tens of metres2-4, hindering the assessment of past and future ice-sheet stability. Here we show that during the mid-Piacenzian Warm Period, which was on average two to three degrees Celsius warmer than the pre-industrial period5, the GMSL was about 16.2 metres higher than today owing to global ice-volume changes, and around 17.4 metres when thermal expansion of the oceans is included. During the even warmer Pliocene Climatic Optimum (about four degrees Celsius warmer than pre-industrial levels)6, our results show that the GMSL was 23.5 metres above the present level, with an additional 1.6 metres from thermal expansion. We provide six GMSL data points, ranging from 4.39 to 3.27 million years ago, that are based on phreatic overgrowths on speleothems from the western Mediterranean (Mallorca, Spain). This record is unique owing to its clear relationship to sea level, its reliable U-Pb ages and its long timespan, which allows us to quantify uncertainties on potential uplift. Our data indicate that ice sheets are very sensitive to warming and provide important calibration targets for future ice-sheet models7.


Asunto(s)
Cambio Climático/historia , Agua de Mar/análisis , Calibración , Dióxido de Carbono/análisis , Foraminíferos/química , Historia Antigua , Cubierta de Hielo/química , Islas , Mar Mediterráneo , Isótopos de Oxígeno/análisis , España , Incertidumbre
5.
Dig Liver Dis ; 51(6): 901-906, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30975612

RESUMEN

BACKGROUND: Rapid on-site evaluation (ROSE) of cytological specimensacquired with EUS-guided fine needle aspiration (EUS-FNA) represents the most accurate available technique to reach a definitive diagnosis in patients with pancreatic solid masses. Recently, needles with high histological yield have been developed for EUS-guided fine needle biopsy (EUS-FNB), with which the need for ROSE can be potentially overcome. AIMS: The primary aim is to compare the diagnostic accuracy of EUS-FNB with or without ROSE. The main endpoint will be measured against the gold standard diagnosis (surgical pathology whenever available or diagnostic work-up in agreement with a clinical course of at least six months). Secondary endpoints include: (a) safety; (b) presence of tissue core; (c) quality of specimens; (d) time of the sampling procedure. Reliability of macroscopic on-site evaluation (MOSE) by endosonographers will be also assessed. METHODS: FROSENOR is an international randomized non-inferiority ongoing study at sixteen centers in four continents. Eight hundred patients will be randomized in two arms (EUS-FNB + ROSE vs. EUS-FNB alone) and outcomes compared. Sample size has been calculated in order to demonstrate the non-inferiority of FNB alone. Randomization and data collection will be performed online. DISCUSSION: This study will ascertain if ROSE is still needed when performing EUS-FNB of solid pancreatic lesions.


Asunto(s)
Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Páncreas/patología , Neoplasias Pancreáticas/diagnóstico , Estudios de Equivalencia como Asunto , Humanos , Modelos Logísticos , Estudios Multicéntricos como Asunto , Agujas , Reproducibilidad de los Resultados
6.
Sci Total Environ ; 526: 196-203, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25931025

RESUMEN

This study reports radon concentration in the most representative caves of Mallorca, identifying those in which the recommended action level is exceeded, thus posing health risks. Two show caves (Campanet and Artà) and three non-touristic caves (Font, Drac, Vallgornera) were investigated. Data were collected at several locations within each cave for three different periods, from March 2013 to March 2014. Except for Vallgornera, where only one monitoring period was possible, and Artà in which low values were recorded throughout the year, a clear seasonal variability, with higher values during the warm seasons and lower during winter time is prominent. Radon concentrations differed markedly from one cave to another, as well as within the same cave, ranging from below detection limit up to 3060 Bq·m(-3). The results of this study have significant practical implications, making it possible to provide some recommendation to cave administrators and other agencies involved in granting access to the investigated caves.


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Cuevas , Monitoreo de Radiación , Radón/análisis , Islas , España
8.
Science ; 327(5967): 860-3, 2010 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-20150501

RESUMEN

Global sea level and Earth's climate are closely linked. Using speleothem encrustations from coastal caves on the island of Mallorca, we determined that western Mediterranean relative sea level was approximately 1 meter above modern sea level approximately 81,000 years ago during marine isotope stage (MIS) 5a. Although our findings seemingly conflict with the eustatic sea-level curve of far-field sites, they corroborate an alternative view that MIS 5a was at least as ice-free as the present, and they challenge the prevailing view of MIS 5 sea-level history and certain facets of ice-age theory.

11.
s.l; s.n; 1954. 9 p. tab.
No convencional en Español | Sec. Est. Saúde SP, HANSEN, Hanseníase, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1241305

RESUMEN

No hace mucho, José M. Fernández, en un interesante trabajo sobre relaciones entre alergia tuberculosa y lepra, después de definir las formas lepromatosas y tuberculoides de esta última, con sus características clínicas e inmunológicas, insiste sobre la constante positividad de la reacción favorable de la enfermedad de la reacción de Mitsuda en las formas tuberculoides, lo que implicaría la evolución favorable de le enfermedad en este grupo, y se explaya en consideraciones sobre la positividad de esta reacción en personas sanas, tanto para aquellas que han vivido en un ambiente con lepra, como aquellas que han estado siempre alejadas de él, en regiones o países donde la lepra es desconocida.


Asunto(s)
Lepromina/administración & dosificación , Lepra , Lepra/diagnóstico , Lepra/prevención & control , Lepra/tratamiento farmacológico , Vacuna BCG/administración & dosificación
12.
Artículo en Español | PAHO | ID: pah-34183

RESUMEN

Thirty one children of leper parents in the Santa Teresita Preventorium of Asunción, Paraguay, all of them free from leprosy, were vaccinated with BCG after X-ray chest examinations and tuberculin tests which proved positive in 77 per cent. Rosenthal's multipuncture method was used. Among 11, in whom the results of the Mitsuda test were unknown, 82 per cent proved Mitsuda-positive after the vaccination. In 80 per cent of the other 20 the Mitsuda test changed from negative to positive after the vaccination. The following conclusions are given: An antigenic relation between tuberculosis and leprosy does not appear likely. A tuberculous infection cannot be accepted as the cause of a positive Mitsuda reaction. BCG vaccination may change a Mitsuda reaction from negative to postive in 80 per cent of both tuberculin-anergic and allergic cases. This experience suggests the possibility of preventing leprosy by BCG, especially in persons living in an endemic environment, if leprologists accept that a positive Mitsuda reaction implies a relative immunity(AU)


Asunto(s)
Lepromina/inmunología , Salud Infantil , Vacuna BCG/inmunología , Tuberculina/efectos adversos , 28573 , Lepra/diagnóstico , Tuberculosis/diagnóstico , Monitoreo Epidemiológico , Paraguay
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