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El Chichón volcano is the most active volcano in the state of Chiapas, México, and experienced its last Plinian eruption (VEI = 5) in 1982. To better assess its volcanic hazard, we studied its readiness to erupt by estimating changes in its internal stress state. These stress changes are difficult to calculate accurately, for example in the absence of focal mechanisms, but their existence can be indirectly revealed by the presence of volcano-tectonic earthquakes, for example following a large tectonic earthquake. We show that the seismic rate recorded at El Chichón volcano increased slightly after the large Mw8.2 Tehuantepec earthquake of 8 September 2017, Chiapas. However, this rate quickly returned to its background level after only 2 months, without any external volcanic manifestations, suggesting that the volcano is not ready to erupt in the near future. Previous observations of slight increases in the volcanic seismicity rate following large earthquakes have been explained by the presence of active hydrothermal systems in the vicinity of the volcano. We propose a similar explanation for El Chichón volcano which is known for its large hydrothermal system. Furthermore, the characteristics of the 2017 seismicity (spatial and magnitude distributions), and the horizontal-to-vertical spectral ratio also confirm the presence of high amounts of water near the volcano. We show that the 2017 volcano-tectonic seismicity is of hydrothermal rather than magmatic origin, in agreement with recent independent geochemical and aeromagnetic studies. [ABSTRACT FROM AUTHOR]

In this study, we analyse the 2020 seismic swarm that lasted two months and occurred between the Tancítaro and the Paricutin volcanoes in the Michoacán Guanajuato Volcanic Field, Mexico. We developed a new method to automatically detect and locate about 100   000 earthquakes, enabling us to track the magma migration through narrow dykes. Additionally, we reveal the presence of two magma reservoirs from two seismic noise tomography results. The first reservoir is located from 8 to 20 km below sea level and beneath the Tancítaro volcano and probably corresponds to a complex network of dykes and sills. This crustal reservoir is fed by a mantle reservoir with a wide horizontal extension between 35 and 50 km below sea level. The seismic swarm initiated beneath the Tancítaro summit in the lower portion of the crustal magma reservoir. At this stage, the seismicity migration was mainly horizontal, which we interpret as its response to the higher normal stress caused by the gravitational load of Tancítaro. Once the magma was displaced laterally from beneath Tancítaro, magma migration became more vertical. The swarm reached the upper portion of the crustal magma reservoir but did not escape it. We also reveal the effect of a distant but strong tectonic earthquake on the seismic swarm. Before its occurrence, magma migration followed several paths; afterwards, it became more focused along a single path. Finally, after the swarm, we observed a second type of seismicity called post-swarm seismicity, with a lower earthquake rate but with higher magnitudes. The hypocentres were diffuse and horizontally centred on the previous swarm location. Furthermore, some earthquakes were aligned along shallow faults, generating a high seismic risk to the different Tancítaro nearby localities. [ABSTRACT FROM AUTHOR]

Monogenetic structures located at the southern and western ends of the Chichinautzin volcanic field (Trans-Mexican Volcanic Belt, Central Mexico) yield 40Ar/ 39Ar ages ranging from 1.2 Ma in the western portion of the field to 1.0–0.09 Ma in the southern portion, all of which are older than the <0.04 Ma age previously established for the entire volcanic field. These new ages indicate: (1) an eruption rate of 0.47 km 3/kyr, which is much lower than the 11.7 km 3/kyr previously estimated; (2) that the Chichinautzin magmatism coexisted with the Zempoala (0.7 Ma) and La Corona (1.0 Ma) polygenetic volcanoes on the southern edge of Las Cruces Volcanic Range (Trans-Mexican Volcanic Belt); and confirm (3) that the drainage system between the Mexico and Cuernavaca basins was closed during early Pleistocene forming the Texcoco Lake. Whole-rock chemistry and Sr, Nd, and Pb isotopic data indicate heterogeneous magmatism throughout the history of Chichinautzin activity that likely reflects variable degrees of slab and sediment contributions to the mantle wedge, fractional crystallization, and crustal assimilation. Even with the revised duration of volcanism within the Chichinautzin Volcanic Field, its eruption rate is higher than most other volcanic fields of the Trans-Mexican Volcanic Belt and is comparable only to the Tacámbaro-Puruaran area in the Michoacán-Guanajuato Volcanic Field to the west. These variations in eruption rates among different volcanic fields may reflect a combination of variable subduction rates of the Rivera and Cocos plates along the Middle America Trench, as well as different distances from the trench, variations in the depth with respect to the subducted slab, or the upper plate characteristics. [ABSTRACT FROM AUTHOR]

Fibrodysplasia ossificans progressiva (FOP) syndrome is a very rare connective tissue disease characterized clinically by the progressive ossification of the soft tissues, usually with hallux malformation. Material and methods: Three patients diagnosed with FOP during 2006 were clinically, radiographically and tomographically assessed. Results: Three female patients ages 4, 6 and 12 years old with hallux deformity and indurated tumors of the trunk, neck and shoulders. Conclusion: FOP is a rare autosomal dominant genetic disease that manifests itself with ossification of the soft tissues, which progressively limits joint and trunk mobility. [ABSTRACT FROM AUTHOR]

Unlabelled: Fibrodysplasia ossificans gressiva (FOP) syndrome is a very rare connective tissue disease characterized clinically by the progressive ossification of the soft tissues, usually with hallux malformation., Material and Methods: Three patients diagnosed with FOP during 2006 were clinically, radiographically and tomographically assessed., Results: Three female patients ages 4, 6 and 12 years old with hallux deformity and indurated tumors of the trunk, neck and shoulders., Conclusion: FOP is a rare autosomal dominant genetic disease that manifests itself with ossification of the soft tissues, which progressively limits joint and trunk mobility.

Home enteral nutrition is the administration of enteral formulae into the digestive tract using a tube, with the objective of preventing or correcting malnutrition patients who are seen at home. Home enteral nutrition is a type of nutritional support that is growing, that improves the nutritional status of the patient with a lower cost and with a greater quality of life of the family unit than enteral nutrition in the hospital. The prevalence is clearly increasing although the data of the national registers of patients with at home enteral nutrition are under estimated. Patients who are candidates for home enteral nutrition can be all those with an indication for enteral nutrition and whose underlying disease is stabilized or does not require all the technical means of the hospital in a permanent and essential manner. Neoplasias and neurological diseases are those that benefit most from at home enteral nutrition and in all registries each group varies between 30 and 40%. All access routes and all enteral nutrition formulae can be used in patients with home enteral nutrition. The use of percutaneous endoscopic gastrostomies is ever more recommended in patients who need at home enteral nutrition for a period longer than 4 weeks. Since the publication of the Ministerial Order of June 2nd 1998, home enteral nutrition is considered a health care service that can be covered by the Social Security. This order lists a series of disease that are likely to be treated with at home enteral nutrition (in our opinion the list is not complete but it is likely to be changed in the future by an Assessing Committee), and it presents some basic norms that all patients must comply with, regardless of the autonomous community in which they live. Before beginning at home enteral nutrition the training of the patient and/or the family with regard to the management of at home enteral nutrition is essential. The existence of qualified personnel with experience in this nutritional support technique, as well as the collaboration between Primary Care and Specialized Care (Clinical Nutrition Units if these exist in the health care area) is essential for the control and follow up of the patient with at home enteral nutrition.