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Model Sets with Euclidean internal Space
(Cambridge University Press, 0022-11-07) Allendes Cerda, Mauricio; Coronel, Daniel
We give a characterization of inter-model sets with Euclidean internal space. This characterization is similar to previous results for general inter-model sets obtained independently by Baake, Lenz and Moody, and Aujogue. The new ingredients are two additional conditions. The first condition is on the rank of the abelian group generated by the set of internal differences. The second condition is on a flow on a torus defined via the address map introduced by Lagarias. This flow plays the role of the maximal equicontinuous factor in the previous characterizations. © The Author(s), 2023. Published by Cambridge University Press.
Statistical Analysis to Quantify the Impact of Map Type on Estimating Peak Discharge in Non-Instrumented Basins
(Universidad Tecnologica de Bolivar, 0023-08-11) Sierra-Sánchez, Alexandra; Gatica, Gustavo; Paternina-Verona, Duban A; Ramos, Helena M.
The calculation of peak discharge in non-instrumented basins requires including morphometric parameters, which in turn depend on the map type used. This study analyses the impact of and variation in peak discharges of the Caño Ricaurte basin, Colombia, based on three types of maps at different resolution scales. The reference map used was the map made for the detailed designs of the channel analysed, which was extracted from the Master Plan of the City. Additionally, maps from a 90 × 90 m digital elevation model and contour lines extracted from Google Earth were used. The time of concentration was determined by different equations (Kirpich, Témez, Bureau, and TR-55) using the mapping methods described above, and the peak discharge was determined using rainfall-runoff models. © 2023 by the authors.
Can climate knowledge enable Warragamba Dam, Sydney, Australia to be used to manage flood risk?
(Institute of Physics, 0023-12) Devanand, Anjana; Pitman, Andy J; Carvajal, Guido; Khan, Stuart J
Dams that serve a dual purpose of water supply and flood mitigation operate to maintain a defined full supply level of water that balances the two conflicting requirements. To optimize the use of available storage space, the full supply level may be adjusted to reflect changing risks of future water shortages and future flood inflows based on known seasonal variations and current observations. The Warragamba Dam in eastern Australia is located upstream of the populated Hawkesbury-Nepean valley which has one of the largest flood exposures in the country. However, the operating protocol of the reservoir does not include provisions to reduce the full supply level of the dam for flood mitigation. Large scale climate indicators that are known to influence the hydroclimate of this region may potentially contain useful information to inform the dual use of this reservoir, but their utility for this purpose has not been studied. Here we explore whether current observations of large-scale climate along with antecedent catchment conditions can be used to estimate the probability of large inflows into the reservoir in the next 3- and 6 months, to aid flood management. We find that the predictors have a substantial influence on the probability of large inflows. The probability differences during opposite predictor phases vary by season and range from 30% to 70%. Our results indicate that considering current climate information to inform dual use of the Warragamba dam has merit. © 2023 The Author(s). Published by IOP Publishing Ltd.
Relationship of Community Mobility, Vital Space, and Faller Status in Older Adults
(Multidisciplinary Digital Publishing Institute (MDPI), 0024-12) Robles Cruz, Diego; Lira Belmar, Andrea; Fleury, Anthony; Lam, Méline; Castro Andrade, Rossana M.; Puebla Quiñones, Sebastián; Taramasco Toro, Carla
Community mobility, encompassing both active (e.g., walking) and passive (e.g., driving) transport, plays a crucial role in maintaining autonomy and social interaction among older adults. This study aimed to quantify community mobility in older adults and explore the relationship between GPS- and accelerometer-derived metrics and fall risk. Methods: A total of 129 older adults, with and without a history of falls, were monitored over an 8 h period using GPS and accelerometer data. Three experimental conditions were evaluated: GPS data alone, accelerometer data alone, and a combination of both. Classification models, including Random Forest (RF), Support Vector Machines (SVMs), and K-Nearest Neighbors (KNN), were employed to classify participants based on their fall history. Results: For GPS data alone, RF achieved 74% accuracy, while SVM and KNN reached 67% and 62%, respectively. Using accelerometer data, RF achieved 95% accuracy, and both SVM and KNN achieved 90%. Combining GPS and accelerometer data improved model performance, with RF reaching 97% accuracy, SVM achieving 95%, and KNN 87%. Conclusion: The integration of GPS and accelerometer data significantly enhances the accuracy of distinguishing older adults with and without a history of falls. These findings highlight the potential of sensor-based approaches for accurate fall risk assessment in community-dwelling older adults. © 2024 by the authors.
COMPARATIVE ANALYSIS OF QUANTITY TAKE-OFF IN CONCRETE, STEEL BARS AND FORMWORK IN APARTMENT BUILDINGS BASED ON CAD AND BIM METHODOLOGIES
(International Council for Research and Innovation in Building and Construction, 0025) Saavedra,Rodrigo; Melendez,Walter; Garces, Gonzalo
Building Information Modeling (BIM) prepares the quantity take-off (QTO) of the construction elements, helping in the management of the design and construction process and preparing the 3D visualization of the construction phases. BIM increases efficiency and gives users more control over construction-related tasks. Construction industry professionals are aware of the advantages of BIM, but because the software BIM is expensive and requires staff training, BIM is not yet widely used. The present investigation identifies the New Cycle building as a Case Study, in which inconsistencies were detected in the QTO, compared to the real quantities of budgeted materials, so the interested parties decided to implement BIM in the use of QTO as a mechanism of control. The central question addressed was: If BIM had been implemented at the tender stage, could it have provided benefits to the project? To do this, various parameters were evaluated that allowed a comparative analysis to be carried out between the results obtained through the use of the CAD and BIM methodology in the same project. In addition, the work processes associated with both methodologies were studied and the perception of CAD and BIM users in the Architecture, Engineering & Construction (AEC) industry was analyzed through the Delphi method. Using the Analytical Hierarchy Process (AHP) method, it was possible to evaluate and compare the two alternatives, CAD and BIM, in order to determine which of them would have been more effective in satisfying the objectives set in the project, considering various variables, both technical and economical. The study highlights the advantages of BIM over CAD for QTO in construction projects, providing valuable information for informed decision making in future projects. However, BIM adoption faces challenges such as the need for specialized training, industry resistance to change, complex workflows, and investments in software and hardware. To overcome these barriers, it is recommended to implement comprehensive training programs, foster a culture of innovation and collaboration, simplify BIM-QTO workflows, and explore scalable and accessible technological solutions. © 2025 The author(s).
Harnessing evolutionary algorithms for enhanced characterization of ENSO events
(Springer, 0025-01) Abdulkarimova, Ulviya; Abarca-del-Rio, Rodrigo; Collet, Pierre
The El Niño-Southern Oscillation (ENSO) significantly influences the complexity and variability of the global climate system, driving its variability. ENSO events’ irregularity and unpredictability arise from intricate ocean–atmosphere interactions and nonlinear feedback mechanisms, complicating their prediction of timing, intensity, and geographic impacts. This study applies Genetic Programming and Genetic Algorithms within the EASEA (EAsy Specification of Evolutionary Algorithms) Evolutionary Algorithms (EA) framework to develop a repository of symbolic equations for El Niño and La Niña events, spanning their various intensities. By analyzing data from the Oceanic Niño Index, this approach yields equation-based characterizations of ENSO events. This methodology not only enhances ENSO characterization strategies but also contributes to expanding the use of EAs in climate event analysis. The resulting equations have the potential to offer insights beyond academia, benefiting education, climate policy, and environmental management. This highlights the importance of ongoing refinement, validation, and exploration in these fields through EAs. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Mathematics classroom explanation: a literature review
(HISIN (History of Information Systems), 0025-01) Valdes, Gabriel
Research on explanation in the teaching of mathematics at the secondary education level is crucial for improving understanding and the effective learning of mathematical concepts. This study focuses on analyzing empirical research that has addressed the explanation in the teaching of mathematics at the secondary level, published in the last five years in journals indexed in the Web of Science. Methodology: A systematic analysis is carried out, following the PRISMA methodology to ensure a systematic and reproducible analysis. Results: The findings highlight that research at the primary and secondary educational levels on mathematical explanation is scarce. Studies with teaching innovations predominate. Discussions: The need for ongoing training for teachers is discussed, emphasizing the importance of clear explanations tailored to the needs of the students to facilitate deep and enduring learning, as well as the practical implications of the study. Conclusions: This study underscores the opportunity to expand research in this field to enrich pedagogical practices and improve the teaching of mathematics at fundamental educational levels. © 2025, HISIN (History of Information Systems). All rights reserved.
Applying Machine Learning Sampling Techniques to Address Data Imbalance in a Chilean COVID-19 Symptoms and Comorbidities Dataset
(Multidisciplinary Digital Publishing Institute (MDPI), 0025-02) Ormeño-Arriagada, Pablo; Márquez, Gastón; Araya, David; Rimassa, Carla; Taramasco, Carla
Reliably detecting COVID-19 is critical for diagnosis and disease control. However, imbalanced data in medical datasets pose significant challenges for machine learning models, leading to bias and poor generalization. The dataset obtained from the EPIVIGILA system and the Chilean Epidemiological Surveillance Process contains information on over 6,000,000 patients, but, like many current datasets, it suffers from class imbalance. To address this issue, we applied various machine learning algorithms, both with and without sampling methods, and compared them using different classification and diagnostic metrics such as precision, sensitivity, specificity, likelihood ratio positive, and diagnostic odds ratio. Our results showed that applying sampling methods to this dataset improved the metric values and contributed to models with better generalization. Effectively managing imbalanced data is crucial for reliable COVID-19 diagnosis. This study enhances the understanding of how machine learning techniques can improve diagnostic reliability and contribute to better patient outcomes. © 2024 by the authors.
Long-lived particle phenomenology in one-loop neutrino mass models with dark matter
(Springer Science and Business Media Deutschland GmbH, 0025-02) Arbeláez, Carolina; Cottin, Giovanna; Helo, Juan Carlos; Hirsch, Martin; de Melo, Téssio B.
Neutrino masses and dark matter (DM) might have a common origin. The scotogenic model can be considered the proto-type model realizing this idea, but many other variants exist. In this paper we explore the phenomemology of a particular DM neutrino mass model, containing a triplet scalar. We calculate the relic density and check for constraints from direct detection experiments. The parameter space of the model, allowed by these constraints, contains typically a long-lived or quasi-stable doubly charged scalar, that can be searched for at the LHC. We reinterpret existing searches to derive limits on the masses of the scalars of the model and estimate future sensitivities in the high-luminosity phase of the LHC. The searches we discuss can serve to constrain also many other 1-loop neutrino mass models. © The Author(s) 2025.
Mesalazine solubility in supercritical carbon dioxide with and without cosolvent and modeling
(Nature Research, 0025-12) Sajadian, Seyed Ali; Esfandiari, Nadia; Rojas, Adrián; Hemmati, Salar; Jouyban, Abolghasem; Aguila, Gonzalo; Garlapati, Chandrasekhar
In this study, the solubility of mesalazine in supercritical carbon dioxide with and without cosolvent was carried out for the first time at different temperatures and pressure values ranging from 308 to 338 K and 12 to 30 MPa, respectively. The determined experimental molar solubilities of mesalazine in supercritical carbon dioxide were in the range of 4.41 × 10–5 to 9.97 × 10–5 (308 K), 3.9 × 10–5 to 13.1 × 10–5 (318 K), 3.4 × 10–5 to 16 × 10–5 (328 K) and 3.3 × 10–5 to 18.4 × 10–5 (338 K). Meanwhile, the determined experimental molar solubilities in supercritical carbon dioxide using 2% dimethyl sulfoxide as cosolvent were in the range of 28.22 × 10–5 to 36.2 × 10–5 (308 K), 26.07 × 10–5 to 51.41 × 10–5 (318 K), 25.02 × 10–5 to 69.07 × 10–5 (328 K) and 25.86 × 10–5 to 82.6 × 10–5 (338 K). A novel association model was employed to simulate the solubility data of the binary and ternary systems. Various semiempirical correlations were utilized to calculate the solubility of mesalazine in supercritical carbon dioxide. The new association model was deemed the most superior model, achieving an average absolute relative deviation value of 4.13% without a cosolvent, and 3.36% when a cosolvent was included. © The Author(s) 2025.
Mesalazine solubility in supercritical carbon dioxide with and without cosolvent and modeling
(Nature Research, 0025-12) Sajadian, Seyed Ali; Esfandiari, Nadia; Rojas, Adrián; Hemmati, Salar; Jouyban, Abolghasem; Aguila, Gonzalo; Garlapati, Chandrasekhar
In this study, the solubility of mesalazine in supercritical carbon dioxide with and without cosolvent was carried out for the first time at different temperatures and pressure values ranging from 308 to 338 K and 12 to 30 MPa, respectively. The determined experimental molar solubilities of mesalazine in supercritical carbon dioxide were in the range of 4.41 × 10–5 to 9.97 × 10–5 (308 K), 3.9 × 10–5 to 13.1 × 10–5 (318 K), 3.4 × 10–5 to 16 × 10–5 (328 K) and 3.3 × 10–5 to 18.4 × 10–5 (338 K). Meanwhile, the determined experimental molar solubilities in supercritical carbon dioxide using 2% dimethyl sulfoxide as cosolvent were in the range of 28.22 × 10–5 to 36.2 × 10–5 (308 K), 26.07 × 10–5 to 51.41 × 10–5 (318 K), 25.02 × 10–5 to 69.07 × 10–5 (328 K) and 25.86 × 10–5 to 82.6 × 10–5 (338 K). A novel association model was employed to simulate the solubility data of the binary and ternary systems. Various semiempirical correlations were utilized to calculate the solubility of mesalazine in supercritical carbon dioxide. The new association model was deemed the most superior model, achieving an average absolute relative deviation value of 4.13% without a cosolvent, and 3.36% when a cosolvent was included. © The Author(s) 2025.
Regulation of a novel Acidithiobacillus caldus gene cluster involved in metabolism of reduced inorganic sulfur compounds
(American Society for Microbiology, 0027-11-01) Rzhepishevska, Olena I.; Valdes, Jorge; Marcinkeviciene, Liucija; Gallardo, Camelia Algora; Meskys, Rolandas; Bonnefoy, Violaine; Holmes, David S.; Dopson, Mark
Acidithiobacillus caldus has been proposed to play a role in the oxidation of reduced inorganic sulfur compounds (RISCs) produced in industrial biomining of sulfidic minerals. Here, we describe the regulation of a new cluster containing the gene encoding tetrathionate hydrolase (tetH), a key enzyme in the RISC metabolism of this bacterium. The cluster contains five cotranscribed genes, ISac1, rsrR, rsrS, tetH, and doxD, coding for a transposase, a two-component response regulator (RsrR and RsrS), tetrathionate hydrolase, and DoxD, respectively. As shown by quantitative PCR, rsrR, tetH, and doxD are upregulated to different degrees in the presence of tetrathionate. Western blot analysis also indicates upregulation of TetH in the presence of tetrathionate, thiosulfate, and pyrite. The tetH cluster is predicted to have two promoters, both of which are functional in Escherichia coli and one of which was mapped by primer extension. A pyrrolo-quinoline quinone binding domain in TetH was predicted by bioinformatic analysis, and the presence of an o-quinone moiety was experimentally verified, suggesting a mechanism for tetrathionate oxidation.
The influence of information delivery on risk ranking by lay people
(ROUTLEDGE JOURNALS, 2006-09-01) Gutiérrez, VV; Cifuentes, LA; Bronfman, NC
An experiment was conducted in a real environment to test how information delivery affects risk ranking. Another aim was to propose the best format for delivering information. Different people received different types of information about risks in a risk ranking exercise: Group 1 received a descriptive paragraph about the hazards (Format 1); Group 2 added a table with specific information on risk attributes (Format 2); Group 3 added information on the steps taken locally to mitigate the risks (Format 3), and Group 4 received a data table without identifying the hazard (Format 4). Agreement among subjects' rankings within a group and from group to group was used to measure the potential impact of information delivery. Average pair-wise Spearman correlation was used to compare the level of agreement within each group. Results showed greater consensus in the group using Format 4 than in Formats 1, 2, and 3, with the only significant difference between Format 4 and each one of the others. The results show that the amount of information, and the way it is delivered, may affect how lay people rank risks, but the differences are not statistically significant.
Accounting for variation in the explanatory power of the psychometric paradigm: The effects of aggregation and focus
(ROUTLEDGE JOURNALS, 2007-01-01) Bronfman, NC; Cifuentes, LA; Dekay, ML; Willis, HH
Most psychometric studies of risk perception have used data that have been averaged over participants prior to analysis. Such aggregation obscures variation among participants and inflates the magnitude of relationships between psychometric dimensions and dependent variables such as overall riskiness. However, most studies that have not averaged data over participants have also shifted the focus of analysis from differences among hazards to differences among participants. Hence, it is unclear whether observed reductions in the explanatory power of psychometric dimensions result from the change in the level of analysis or from the change in the focus of analysis. Following Willis et al.'s ( 2005) analysis of ecological risk perceptions, we unconfound these two variables in a study of risk perceptions in Santiago, Chile, although we use more traditional hazards, attributes, and statistical procedures. Results confirm that psychometric dimensions explain less variation in judgments of riskiness and acceptability at the disaggregate level than at the aggregate level. However, they also explain less variation when the focus of analysis is differences among participants rather than differences among hazards. These two effects appear to be similar in magnitude. A simple hybrid analysis economically represents variation among participants' judgments of hazards' riskiness by relating those judgments to a common set of psychometric dimensions from a traditional aggregate-level analysis.
Remoción mediante vermicomposteo de los coliformes fecales presentes en lodos biológicos
(Facultad de Ingeniería, Universidad de Antioquia, 2009) Droppelmann, Carmen Verónica; Gaete, Carolina Pía; Miranda, Paulina
En este trabajo se buscó establecer el efecto de la densidad inicial de lombrices en la remoción de patógenos, mediante vermicomposteo de lodo, usando como indicador el número más probable de coliformes fecales (NMPCF). El lodo utilizado se generó en una planta de aireación extendida, se trabajó con 4 densidades: alta con 0,2 kg lombrices/kg lodo, media con 0,1 kg lombrices/ kg lodo, baja con 0,05 kg lombrices/kg lodo y un blanco sin la adición de lombrices al lodo. Al segundo día de experimentación con la densidad media se logró una mayor remoción, estadísticamente significativa, del NMPCF que la obtenida con la densidad alta. El mismo día, todas las densidades lograron la clasificación de lodo clase B según United States Enviroment Protection Agency. Entre el día 13 y el 20 las muestras con densidades alta, baja y media lograron la clasificación clase A, no así el blanco. Al día 20 tanto la densidad media como la alta lograron el 100% de remoción de los coliformes fecales.
Detección de pérdidas en tuberías de agua: propuesta basada en un banco de filtros
(2009) Castro Burgos, Lucía; Valdés-González, Héctor
Actualmente la detección de pérdidas (DP) en tuberías de agua es un área de investigación activa, y con un creciente interés, debido a la importancia del transporte seguro del vital elemento. Este trabajo considera el problema de DP en tuberías de agua por medio de redundancia analítica, basada en un modelo matemático y utilizando técnicas de estimación de estados, teniendo por objetivo principal estudiar, proponer, implementar y aplicar algoritmos eficientes que permitan abordar de manera general el problema de DP. Para lograr esto se propone y evalúa un banco de filtros, implementados con filtros de Kalman (FK) y filtros de partículas (FP). Con esto se busca contribuir conceptualmente a la formulación del problema de DP, de manera modular, permitiendo que en un estudio futuro otras técnicas puedan ser utilizadas para resolver el problema. Además, obtener algoritmos eficientes y confiables, basados en un estimador de estados capaces de responder a requerimientos industriales, tales como: entregar, a partir de medidas de entrada y salida disponibles, una estimación fiable del estado del proceso, esto con independencia de la dinámica lineal o no lineal, asimismo, ser de fácil manejo y fácil configuración. La simulación computacional y los resultados experimentales muestran la efectividad de combinar FP con FK, para el caso básico de dos pérdidas secuenciales en una tubería, presentando ventajas de rápida convergencia y reducción del error de estimación, factores importantes en el problema de DP en ductos hídricos. Palabras clave: Detección de pérdidas, banco de filtros, filtro de Kalman, filtro de partículas. -------------------------------------------------------------------------------- ABSTRACT Currently leak detection (LD) in water pipelines is an active area of research that is attracting increasing interest due to the importance of the safe transport of this vital resource. This work considers the problem of LD in water pipes by means of analytical redundancy, based on a mathematical model and using state estimation techniques. The main aim of this work is to research, propose, implement and apply efficient algorithms that allow to tackle generally the LD. To achieve this, a bank of filters including Kalman Filters (KF) and Particle Filter (PF) is proposed and evaluated. Thus a conceptual contribution to the formulation of the LD problem is proposed in a modular way so that future studies of other techniques can solve the problem. In addition, efficient and reliable algorithms are developed, based on a state estimator capable of responding to industrial standards such as the delivery, from input and output measures available, of a reliable estimate of the state of the process and that is independent of the linear or non-linear dynamics and easy to handle and configure. The computer simulation and the experimental results show the effectiveness of combining KF with PF for the simple case of two sequential leaks in a pipe, presenting advantages such as rapid convergence and reducing the estimation error which are important factors in LD in water pipeline. Keywords: Leak detection, bank of filters, Kalman filter, particle filter.
Métodos de estimación no lineal aplicados Al problema de expectativas de inflación
(2014 Universidad de Tarapacá, 2009) Arriagada-Benítez, Mauricio; Valdés-González, Héctor; Pedraja-Rejas, Liliana
En este trabajo se describe y analiza, luego de tener la ecuación que relaciona la dinámica de las expectativas de la tasa de interés real y de la inflación, el filtro extendido de Kalman. Asimismo, se realiza la estimación de la inflación exante para una serie de datos preestablecida. Se efectúa una comparación con el método de estimación de horizonte móvil utilizado en situaciones cuando producto de las incertidumbres paramétricas del modelo éste se torna no lineal. La aplicación de estos métodos a datos reales permite concluir que las estimaciones efectuadas a través del método de horizonte móvil, combinado a un algoritmo heurístico de optimización logran los mejores resultados. Palabras clave: Filtrado de Kalman, método MHSE, inflación, modelos econométricos. ABSTRACT This work describes and analyses the Extended Kalman Filter with regard to an equation that relates the dynamic of the expected real interest rates and inflation. An estimation of the exante inflation for a preestablished data set is carried out. This is compared with the same calculation using a moving horizon estimation method for situations that are non lineal due to parametric uncertainties of the model. From the application of these methods to real data, it can be concluded that the estimations based on the moving horizon method, combined with a heuristic optimization algorithm, yield better results. Keywords: Kalman Filter, MHSE method, inflation, econometric models.
USO DE BIOSÓLIDOS COMO REACTIVO ESPUMANTE EN PROCESOS DE FLOTACIÓN: CARACTERIZACIÓN FÍSICA Y QUÍMICA
(Universidad Nacional de Colombia, 2011) REYES-BOZO, LORENZO; HERRERA-URBINA, RONALDO; GODOY-FAÚNDEZ, ALEX; SÁEZ-NAVARRETE, CÉSAR; HERRERA, MIGUEL; GINOCCHIO, ROSANNA
RESUMEN: La flotación espumosa usa diversos reactivos, orgánicos e inorgánicos, para aumentar el rendimiento y selectividad del proceso. La flotación utiliza sustancias tensoactivas que se adsorben en la interfase aire/agua. Como potenciales sustitutos de los espumantes usados actualmente, se consideran los residuos orgánicos de origen animal, como los biosólidos. Este estudio, evalúa el uso de biosólidos y ácidos húmicos como agentes espumantes para flotación espumosa, cuantificándose su capacidad tensoactiva y para formar y estabilizar espumas. Biosólidos son capaces de cambiar la tensión superficial de una solución, crear y estabilizar espumas. Dosis menores a 4 g L-1 muestran un afecto tensoactivo mayor comparado con reactivos espumantes, tipo MIBC. Para un uso efectivo de biosólidos, se requiere realizar una etapa de preacondicionamiento, que permita separar la fracción soluble y coloidal que tiene la capacidad tensoactiva. El uso de biosólidos a gran escala necesita investigación adicional para escalar los resultados obtenidos en laboratorio.
El abate Juan Ignacio Molina: una vida dedicada a la historia natural y civil del reino de Chile
(Asociación Geológica Argentina, 2011-09) Charrier, Reynaldo; Hervé, Francisco
Juan Ignacio Molina (1740-1829) nació cerca de Talca, Chile, y falleció en Bolonia, Italia. Es el primer científico chileno. Desde pequeño se interesó por la naturaleza. Se educó con la Compañía de Jesús en diversos lugares de Chile central, lo que le permitió conocer su geografía, fauna, flora y población. Con 15 años ingresó a la Compañía. En 1767, abandonó el país al ser expulsada esta orden de españa y sus dominios. Se radicó en los Estados Pontificios, donde se ordenó de sacerdote y permaneció hasta su muerte. Allí enseñó ciencias naturales y produjo su obra científica: Compendio de la historia geográfica, natural y civil del reino de Chile de 1776, una versión aumentada, Ensayo sobre la historia natural de Chile de 1782 y una segunda en 1810. En ellas, abordó aspectos climáticos, botánicos, geológicos, zoológicos, mineralógicos y geográficos del territorio. Describió el terremoto de Concepción, las erupciones del Villarrica y Peteroa, e hizo referencia a recursos minerales. Diferenció cuatro unidades litoestratigráficas para Chile central. Clasificó plantas y animales siguiendo los criterios de Linneo. En una de sus 14 memorias, Analogías menos observadas de los tres reinos de la Naturaleza, sin podérselo calificar de evolucionista, se destaca su intento de integración entre los "seres" de los tres reinos, y en Sobre la propagación del género humano en las diversas partes de la tierra, propuso tres vías diferentes para el poblamiento de América. En 1802, ingresó a la Academia de Ciencias de Bolonia.
Evolution of the Great Tehuelche Paleolake in the Torres del Paine National Park of Chilean Patagonia during the Last Glacial Maximum and Holocene
(Servicio Nacional de Geología y Minería, 2012) Solari, Marcelo A.; Le Roux, Jacobus P.; Hervé, Francisco; Airo, Alessandro; Calderón, Mauricio
RESUMEN. Una serie de morrenas glaciares se distribuyen desde el margen oriental de la cuenca de drenaje Torres del Paine a cerca del actual margen de los Campos de Hielo Patagónico, junto con una serie de terrazas lacustres regional continuos relacionados con las fluctuaciones glaciales. La geomorfología, apoyada por la evidencia de sedimentos del lago, indica la existencia de un único paleolago proglacial en esta zona, aquí denominado el Gran Tehuelche paleolago. Este concepto ayuda a aclarar la cronología de eventos glaciales y conduce a una mejor comprensión de la evolución del sistema hidrológico de la zona de Torres del Paine. Avances glaciales referidos anteriormente como ocurrieron A, B y C durante el Último Máximo Glacial y alimentados con la Gran Tehuelche paleolago con agua de deshielo, que le permite alcanzar su máxima extensión. El descubrimiento de trombolitos en Laguna Amarga sugiere que el drenaje de la paleolago hacia el fiordo de Última Esperanza tuvo lugar en 7113 Cal. años AP, después de la fusión de una barrera de hielo que existía durante el avance glacial antes. Esto dio lugar al desarrollo de un sistema hidrológico fluvio-lacustre complejo que persiste hasta nuestros días. Palabras clave: Patagonia, último máximo glacial, Younger Dryas, trombolitos. RESUMEN. Un grupo de morrenas glaciales estan Distribuidas desde el margen Este de la cuenca de drenaje de Torres del Paine Hacia el margen real de los Campos de Hielo Patagónicos. Las morrenas se observan en conjunto con las Naciones Unidas Grupo de terrazas Lacustres Regionales, las Cuales estan vinculadas y una las fluctuaciones glaciales. La geomorfología y Evidencias de sedimentos Lacustres indicano la existence De unico ONU lago proglacial, referido En Este Estudio de Como Gran Paleolago Tehuelche. Este Concepto ayuda a clarificar la cronología de los eventos glaciales y permite Una mejor Comprensión de la Evolución del Sistema hidrológico del sector de Torres del Paine. Los eventos glaciales, previamente Referidos Como Avance A, B y C, ocurrieron Durante el Último Máximo Glacial y alimentaron con Aguas de fusión al Gran Paleolago Tehuelche, permitiéndole Alcanzar su alcalde extensión. El Descubrimiento de trombolitos en Laguna Amarga sugiere Que El desagüe del paleolago Ocurrió Hace 7.113 Cal. Por años AP el Seno de Última Esperanza, producto de la fusión De Una barrera glaciar existente Durante los Avances glaciales Anteriores. LUEGO del drenaje sí Desarrollo en Un complejo Sistema hidrológico Que Persiste Hasta el presente. Palabras clave: Patagonia, Último Máximo Glacial, Dryas Temprano, Trombolitos.

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