Geología y Volcanología de islas volcánicas oceánicas: Canarias-Hawaii

Lecciones didácticas de volcanología de Canarias y Hawaii con abundancia de ilustracionesCaja General de Ahorros de Canaria

Preparation of updated volcanic hazards map for el Misti volcano, Peru

The city centre of Arequipa -second largest city in Peru (about one million people)- is located 17 km away from Misti Volcano (5822 a.s.l.) and about 3.5 km vertically below it. During the last 50,000 years, vulcanian and sub-plinian eruptions at Misti have produced about ten sizeable piroclastic flows and twenty tephra falls (Thouret et al., 2001). However, numerous ash falls, pyroclastic flows, and lahars from prehistoric subplinian eruptions, as recent as 2,000 years ago, have affected the region of Arequipa around the volcano. Misti’s only well-recorded historical activity consisted of small eruptions during the mid-15th century (Chávez, 1992). The Chili River and the main ravines (Pastores, San Lázaro, Huarangal, Huarangueros, Agua Salada) drain the W, S, and SE flanks of the volcanic edifice and cut through Arequipa city. Channeled through them, numerous pyroclastic flows and lahars have reached 12 to 25 km distance from source. Should El Misti Volcano awake in the future the volcanic and hydrological hazards associated with renewed eruptive activity and rainstorms would pose a serious threat to the people, infrastructures, and economy of Arequipa and its environs. Even though a number of volcano hazards maps and assessments have been made in recent years, these have not been entirely satisfactory due to the required detail or appropriate scale for use by decision makers in the preparation of contingency plans and risk-reduction measures. In recognition of El Misti’s enormous potential volcanic threat, the national geological agency of Peru –Instituto Geológico Minero y Metalúrgico del Perú (INGEMMET)– recently has initiated a project to make a detailed geological map and updated volcanic hazard map of El Misti Volcano. This new map will be completed in December 2006

Evaluación de peligros volcánicos y elaboración del mapa de peligros del Volcán Misti - Arequipa

Se presenta una evaluación de peligros volcánicos del Misti para la elaboración de un mapa de peligros actualizado. A su vez, el documento se empleará en programas de educaciòn y sensibilización frente a peligros volcánicos y ante el Plan de Ordenamiento Territorial de la Ciudad de Arequipa. Se anota la formación de un comité científico asesor, que incluye a Defensa Civil, como apoyo a la citada Región

Mapa de peligros del volcán Misti: Una herramienta para la planificación del desarrollo y ordenamiento territorial de la ciudad de Arequipa

Se describe el mapa de peligros del Volcán Misti, el cual tiene como propósito guiar a las autoridades, dirigentes y población en general en políticas de ordenamiento territorial, expansión urbana y planificación del desarrollo. Detalla las tres zonas de peligrosidad, según su grado: a) La zona de alto peligro, puede ser severamente afectada por lluvias de ceniza y pómez, flujos y oleadas piroclásticas, flujos de barro, avalanchas de escombros y/o flujos de lava. b) La zona de moderado peligro, puede ser afectada prácticamente por todos los peligros que alcanzarían la zona anterior, a excepción de flujos de lavas. c) La zona de bajo peligro, puede ser afectada solo por flujos, oleadas y caídas piroclásticas de pómez y/o ceniza, pero en erupciones de magnitud muy grande (IEV > 5), como las ocurridas hace 13 600 y 33 000 años. Se observa que durante los últimos 50 años la ciudad ha crecido de manera desordenada, con escasa planificación. El mapa de peligros muestra que varios sectores de la ciudad de Arequipa se emplazan en zonas de alto peligro, principalmente en áreas aledañas al río Chili y quebradas que drenan del volcán. Los distritos que vienen expandiéndose hacia zonas cercanas al volcán Misti y áreas de alto peligro, generando una mayor vulnerabilidad son Selva Alegre, Miraflores y Paucarpata

Mapa de peligros del volcán Misti

En este mapa se representan con distintos colores las zonas susceptibles a ser afectadas por los fenómenos volcánicos como son las lluvias de ceniza y piedra pómez, flujos y oleadas pirocláslicas, flujos de barro, avalanchas de escombros y flujos de lava. Se distinguen zonas de alto peligro en color rojo, moderado peligro en naranja y bajo peligro en amarillo. La zona cercana al cráter (rojo) es la más peligrosa porque puede ser afectada con mayor frecuencia por todos los fenómenos, mientras que la zona amarilla representa áreas que pueden ser afectadas por pocos fenómenos y sólo en erupciones de excepcional magnitud. La determinación de las tres zonas de peligros está basada en una combinación g o suma de todos los peligros potenciales que pueden afectar dichas áreas. Finalmente, los límites entre cada zona son graduales y no se pueden determinar con exactitud absoluta

Programming of adiposity in childhood and adolescence: Associations with birth weight and cord blood adipokines

© 2017 by the Endocrine Society. Context: Exposure to maternal adiposity during pregnancy is associated with higher offspring birth weight and greater adiposity through childhood and adult life. As birth weight reflects the summation of lean and fat mass, the extent to which fat mass at birth tracks into later life is unknown. Objective: To determine whether fat mass at birth is associated with child and adolescent adiposity. Design, Setting, and Participants: UK birth cohort with markers of neonatal fat mass; cord blood leptin, adiponectin, and birth weight and adiposity outcomes at age 9 (n = 2775) and 17 years (n = 2138). Main Outcomes: Offspring body mass index (BMI), waist circumference, dual-energy X-ray absorptiometry-determined fat mass, and obesity at age 9 and 17 years. Results: Higher cord blood leptin was associated with higher z scores of fat mass [difference in mean per 10 pg/mL: 0.03 standard deviation (SD); 95% confidence interval (CI), 0.00 to 0.06], waist circumference (0.04 SD; 95% CI, 0.00 to 0.07), and BMI (0.04 SD; 95% CI, 0.00 to 0.08) at age 9. However, by age 17 the adjusted results were attenuated to the null. Cord blood adiponectin was not associated with measures of adiposity at age 9. At age 17, cord blood adiponectin was positively associated with fat mass (0.02 SD per 10 mg/mL; 95% CI, 0.02 to 0.03) and waist circumference (0.04 SD per 10 mg/mL; 95% CI, 0.03 to 0.05). Birth weight was positively associated with waist circumference (0.03 SD per 100 g; 95% CI, 0.02 to 0.04) and BMI (0.02 SD per 100 μg; 95% CI, 0.00 to 0.03), but not fat mass or odds of obesity. Cord blood leptin and adiponectin were not associated with obesity at either age. Conclusions: Increased cord blood leptin and adiponectin, known surrogates of fetal fat mass, were weakly associated with increased fat mass in late childhood and adolescence, respectively

Association between perinatal mortality and morbidity and customised and non-customised birthweight centiles: a comparative record-linkage study in Denmark, Finland, Norway, Wales and England

Objectives: To compare the risk of adverse perinatal outcomes according to infants who are born small for gestational age (SGA; 90th centile), as defined by birthweight centiles that are non-customised (ie, standardised by sex and gestational age only) and customised (by sex, gestational age, maternal weight, height, parity, and ethnic group). Design: Comparative, population based, record linkage study with meta-analysis of results. Setting: Denmark, Finland, Norway, Wales, and England (city of Bradford), 1986-2019. Participants: 2 129 782 infants born at term in birth registries. Main outcome measures: Stillbirth, neonatal death, infant death, admission to neonatal intensive care unit, and low Apgar score (<7) at 5 minutes. Results: Relative to those infants born average for gestational age (AGA), both SGA and LGA births were at increased risk of all five outcomes, but observed relative risks were similar irrespective of whether non-customised or customised charts were used. For example, for SGA versus AGA births, when non-customised and customised charts were used, relative risks pooled over countries were 3.60 (95% confidence interval 3.29 to 3.93) versus 3.58 (3.02 to 4.24) for stillbirth, 2.83 (2.18 to 3.67) versus 3.32 (2.05 to 5.36) for neonatal death, 2.82 (2.07 to 3.83) versus 3.17 (2.20 to 4.56) for infant death, 1.66 (1.49 to 1.86) versus 1.54 (1.30 to 1.81) for low Apgar score at 5 minutes, and (based on Bradford data only) 1.97 (1.74 to 2.22) versus 1.94 (1.70 to 2.21) for admission to the neonatal intensive care unit. The estimated sensitivity of combined SGA or LGA births to identify the three mortality outcomes ranged from 31% to 34% for non-customised charts and from 34% to 38% for customised charts, with a specificity of 82% and 80% with non-customised and customised charts, respectively. Conclusions: These results suggest an increased risk of adverse perinatal outcomes of a similar magnitude among SGA or LGA term infants when customised and non-customised centiles are used. Use of customised charts for SGA/LGA births—over and above use of non-customised charts for SGA/LGA births—is unlikely to provide benefits in terms of identifying term births at risk of these outcomes

Assessment of CryoSat-2 interferometric and non-interferometric SAR altimetry over ice sheets

The launch of CryoSat-2 heralded a new era of interferometric Synthetic Aperture Radar altimetry over the Polar Ice Sheets. The mission’s novel SAR interferometric (SARIn) mode of operation has enabled monitoring of rapidly changing coastal regions, which had been challenging for previous low resolution altimeters. Given the growing requirement to continue the 25-year altimeter record, there is now a need to assess the differences between existing SAR and SARIn altimeter datasets, with a view to understanding the impact on ice sheet retrievals of the different radar hardware and processing methodologies. Uniquely, CryoSat-2 data can be processed both with and without interferometric information, offering the opportunity to directly compare the SAR and SARIn products generated by the current ground segment. Here, we provide a first comparison of these Level-2 datasets, and evaluate their capacity to measure ice sheet elevation and elevation change. We find that the current interferometric product has substantially improved precision, accuracy and coverage compared to its non-interferometric counterpart, yielding a ∼35% improvement in the root-mean-square-difference (RMSD) of elevations recorded at orbital cross-overs, and a ∼30% lower RMSD of elevation rates relative to Operation IceBridge airborne altimeter measurements. This analysis demonstrates the value that the interferometer adds to the current CryoSat-2 configuration, and highlights the importance for non-interferometric SAR Level-2 processing of the auxiliary data used to identify the location of the echoing point. These results provide a benchmark of the relative performance of the Level-2 interferometric and non-interferometric products currently produced by the ground segment, which will help to inform the design and implementation of a future polar radar altimeter mission

Genomic HIV RNA Induces Innate Immune Responses through RIG-I-Dependent Sensing of Secondary-Structured RNA

Contains fulltext : 108031.pdf (publisher's version ) (Open Access)BACKGROUND: Innate immune responses have recently been appreciated to play an important role in the pathogenesis of HIV infection. Whereas inadequate innate immune sensing of HIV during acute infection may contribute to failure to control and eradicate infection, persistent inflammatory responses later during infection contribute in driving chronic immune activation and development of immunodeficiency. However, knowledge on specific HIV PAMPs and cellular PRRs responsible for inducing innate immune responses remains sparse. METHODS/PRINCIPAL FINDINGS: Here we demonstrate a major role for RIG-I and the adaptor protein MAVS in induction of innate immune responses to HIV genomic RNA. We found that secondary structured HIV-derived RNAs induced a response similar to genomic RNA. In primary human peripheral blood mononuclear cells and primary human macrophages, HIV RNA induced expression of IFN-stimulated genes, whereas only low levels of type I IFN and tumor necrosis factor alpha were produced. Furthermore, secondary structured HIV-derived RNA activated pathways to NF-kappaB, MAP kinases, and IRF3 and co-localized with peroxisomes, suggesting a role for this organelle in RIG-I-mediated innate immune sensing of HIV RNA. CONCLUSIONS/SIGNIFICANCE: These results establish RIG-I as an innate immune sensor of cytosolic HIV genomic RNA with secondary structure, thereby expanding current knowledge on HIV molecules capable of stimulating the innate immune system