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Ceboruco Volcano is a Quaternary stratovolcano located in Nayarit near the Trans-Mexican Volcanic Belt western limit. It is one of the most active in the region and the only volcano in Nayarit with historically documented eruptions, the last one between 1870 and 1875. Currently, seismicity and fumarolic activity suggest hydrothermal activity. To study the geoelectrical setting at Ceboruco Volcano and its hydrothermal system, a magnetotelluric exploration campaign was carried out in November 2016, establishing 24 measuring stations at the caldera, and foothills of the volcanic edifice. Three broadband instruments were used in the sampling frequency range of 32,768–128 Hz. Recorded time series were processed to determine the MT transfer functions using a robust algorithm and consider the remote-reference station technique. Dimensionality analysis based on the phase tensor determined a shallow 1D geoelectrical structure at periods shorter than 1 s, while a 3D formation was defined at longer periods. To approximate the Ceboruco Volcano substructure, the 3D inversion of magnetotelluric data was carried out. 3D modeling revealed surficial resistivity regions that were related to young volcanic deposits. A relative conductor (10–30 Ωm) was also associated with the shallow regional aquifer. The two most intriguing results of 3D inversion were one uppermost conductive region (~1 Ωm) that established characteristics, resistivity, position, and thickness related to a clay alteration minerals zone. The other one (2–5 Ωm) corresponds to a conductive area broadening and fading with depth, centered slightly to the west of the summit at Ceboruco Volcano. The preferred interpretation of this geoelectrical feature was an envelope of high-temperature fluids, convection of steam, and brines, and they are interacting with the host-rock and surficial groundwater. This geoelectrical feature extends in depth, suggesting a permeable region at the Trans-Mexican Volcanic Belt basement that may be targeted for in-depth geothermal exploration. The geoelectrical setting identified in this study provides information that contributes to reducing uncertainty about the geological, geophysical, and hydrogeological conceptual models at Ceboruco Volcano geothermal system. • Geoelectrical modeling at the active Ceboruco Volcano from magnetotelluric data • Definition of a propitious region to store geothermal fluids • Geoelectrical evidence of fractured-permeable basement regions beneath the volcano • First geophysical evidence from the clay cap at Ceboruco geothermal reservoir • Refinement of geological, geophysical, and hydrogeological conceptual models [ABSTRACT FROM AUTHOR]

Popocatepetl volcano located in central Mexico has been erupting since December 1994 and since then many studies have been carried out in order to understand its eruptive behavior and assess the volcanic hazard since more than 25 million people are at risk. Nevertheless, few geophysical studies have been conducted in order to image the structure of the volcano. For this reason, we carried out magnetotelluric and gravity surveys on the northern flank of the volcano and also modeled magnetic data for the area. In this paper we provide new insight into the structure of the northern part of this complex volcanic structure, which is made up of several volcanoes that had been camouflaged by later pyroclastic deposits from recent eruptions. Results show major northwest-and northeast trending faults in the area that displaced blocks toward the south. These scarps are related to sector collapses. The oldest part of the complex, the Tlamacas volcano was identified by the discontinuities inferred from gravity, magnetic and magnetotelluric data. Electrical resistivity distribution also shows the existence of a lack of continuity in a conductive horizon on the eastern side of the prospected area, which coincides with the location of the hypocenter of the May 6, 2013 earthquake. This feature also corresponds to the position of Tlamacas Volcano and its late dome, that is also faulted, confirming that the NE-SW trending fault is still active. Faulting inferred from geophysical data and confirmed by the occurrence of earthquakes and vent alignment suggests the structural control on magma ascent and the weakness of the southeastern flank of the volcano. • Geophysical evidence unravels structure of the Popocatepetl volcanic complex. • Sector collapse features are constrained by magnetotellurics, aeromagnetics and gravity at Popocatepetl volcano. • Active faulting and structural weakness of the eastern flank of the volcano. [ABSTRACT FROM AUTHOR]

Introduction: While Latin America (LatAm) is facing an increasing burden of dementia due to the rapid aging of the population, it remains underrepresented in dementia research, diagnostics, and care., Methods: In 2023, the Alzheimer's Association hosted its eighth satellite symposium in Mexico, highlighting emerging dementia research, priorities, and challenges within LatAm., Results: Significant initiatives in the region, including intracountry support, showcased their efforts in fostering national and international collaborations; genetic studies unveiled the unique genetic admixture in LatAm; researchers conducting emerging clinical trials discussed ongoing culturally specific interventions; and the urgent need to harmonize practices and studies, improve diagnosis and care, and use affordable biomarkers in the region was highlighted., Discussion: The myriad of topics discussed at the 2023 AAIC satellite symposium highlighted the growing research efforts in LatAm, providing valuable insights into dementia biology, genetics, epidemiology, treatment, and care., (© 2024 The Authors. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)

Hotspots of chronic kidney disease of unknown etiology (CKDu) have been identified throughout the globe, of which the Mesoamerican nephropathy in Central America is the most conspicuous example. It affects mainly agricultural workers, heat exposure during extenuating shifts leading to sudden dehydration and subsequent acute kidney injury (AKI) episodes is the main hypothesis, with other factors such as environmental and social determinants playing an underlying role. Recent reports have suggested that Mexico and the United States may have newly identified CKDu hotspots. Studies from Tierra Blanca, a rural region in Mexico, have shown that the prevalence of probable CKD is high (25%) among the population, of which almost half of the identified cases had no known risk factor (such as diabetes or hypertension). Studies in Hispanic agricultural workers from California and Florida have shown that heat stress and dehydration is frequent and is correlated with AKI episodes after a work shift (33% of workers in one shift). Because recurrent AKI is an established risk factor for CKD, these studies strengthen the evidence that suggests an association between this occupational exposure and CKD. Whether the etiology responsible for the entities described is the same as in other CKDu hotspots in the world remains unknown. The development of preventative and intervention strategies is the most urgent priority to address this issue., (Copyright © 2019 Elsevier Inc. All rights reserved.)