17 research outputs found

    Shaking earth: Non-linear seismic processes and the second law of thermodynamics: A case study from Canterbury (New Zealand) earthquakes

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    We would like to express our gratitude to GeoNet for making available the data used in this work. This work was partially sup-ported by the RNM104 and RNM194 (Research Groups belonging to Junta de Andalucia, Spain) , the Spanish National Projects [grant project PID2019-109608GB-I00] , and the Junta de Andalucia Project [grant project A-RNM-421-UGR18] . English language editing was performed by Tornillo Scientific.Earthquakes are non-linear phenomena that are often treated as a chaotic natural processes. We propose the use of the Second Law of Thermodynamics and entropy, H, as an indicator of the equilibrium state of a seismically active region (a seismic system). In this sense, in this paper we demonstrate the exportability of first principles (e.g., thermodynamics laws) to others scientific fields (e.g., seismology). We suggest that the relationship between increasing H and the occurrence of large earthquakes reflects the irreversible transition of a system. From this point of view, a seismic system evolves from an unstable initial state (due to external stresses) to a state of reduced stress after an earthquake. This is an irreversible transition that entails an increase in entropy. In other words, a seismic system is in a metastable situation that can be characterised by the Second Law of Thermodynamics. We investigated two seismic episodes in the Canterbury area of New Zealand: the 2010 Christchurch earthquake (M = 7.2) and the 2016 Kaikoura earthquake (M = 7.8). The results are remarkably in line with our theoretical forecasts. In other words, an earthquake, understood as an irreversible transition, must results in an increase in entropy.Research Groups belonging to Junta de Andalucia, Spain RNM104- RNM194Spanish National Projects PID2019-109608GB-I00Junta de Andalucia A-RNM-421-UGR1

    Tsallis Entropy and Mutability to Characterize Seismic Sequences: The Case of 2007–2014 Northern Chile Earthquakes

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    Partial support from the following two Chilean sources is acknowledged: Fondecyt under contract 1230055, Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia (Chile) through the Center for Development of Nanoscience and Nanotechnology (CEDENNA) under contract AFB220001. This research has been partially supported by the Agencia Estatal de Investigación (grant no. PID2021-124701NBC21 y C22); the Universidad de Almería (grant no. FEDER/UAL Project UAL2020-RNM-B1980); the Consejería de Universidad, Investigación e Innovación, Junta de Andalucía (grant no. RNM104). PPITUAL, Junta de Andalucía-FEDER 2021–2027. Programa: 54.A. A.P., D.P. and E.E.V. have been partially funded by the Spanish Project LEARNIG PID2022-143083NB-I00 by the Agencia Estatal de Investigación.Seismic data have improved in quality and quantity over the past few decades, enabling better statistical analysis. Statistical physics has proposed new ways to deal with these data to focus the attention on specific matters. The present paper combines these two progressions to find indicators that can help in the definition of areas where seismic risk is developing. Our data comes from the IPOC catalog for 2007 to 2014. It covers the intense seismic activity near Iquique in Northern Chile during March/April 2014. Centered in these hypocenters we concentrate on the rectangle Lat−18 −22 and Lon−72 −68 and deepness between 5 and 70 km, where the major earthquakes originate. The analysis was performed using two complementary techniques: Tsallis entropy and mutability (dynamical entropy). Two possible forecasting indicators emerge: (1) Tsallis entropy (mutability) increases (decreases) broadly about two years before the main MW 8.1 earthquake. (2) Tsallis entropy (mutability) sharply decreases (increases) a few weeks before the MW 8.1 earthquake. The first one is about energy accumulation, and the second one is because of energy relaxation in the parallelepiped of interest. We discuss the implications of these behaviors and project them for possible future studies.Consejería de Universidad, Investigación e Innovación, Junta de Andalucía PID2022-143083NB-I00, RNM104Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia AFB220001Fondo Nacional de Desarrollo Científico y Tecnológico 1230055 FONDECYTAgencia Estatal de Investigación PID2021-124701NBC21 y C22 AEIUniversidad de Almería UAL2020-RNM-B1980 UA

    Preservation of the Iberian Tethys paleomargin beneath the eastern Betic mountain range

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    We are grateful to the staff involved in the TransCorBe project. The Geophysical Instrument Pool at GFZ-Potsdam provided most of the seismic equipment. We are grateful to Christian Haberland for his support. We want to thank two anonymous reviewers for the careful reading of the manuscript and the interesting and constructive criticism they provided. This work was funded by the Spanish State Research Agency (SRA) under the grant PID2019-109608GB I00/SRA/10.13039/501100011033, FEDER/MINECO project CGL2015-67130-C2-2-R, FEDER/Junta de Andalucia project A-RNM-421-UGR18 and research group RNM104 of the Junta de Andalucia. The Granada University/CBUA funding for open access charge.We obtain P-wave receiver functions from teleseismic earthquake recordings at a dense seismic broadband transect, deployed along 170 km across the Betic mountain range in southeastern Spain. Migrated images show the crustal structure of the orogen in detail. In particular, they reveal the situation of the subducted Iberian paleomargin, with full preservation of the proximal domain and the 50 km wide necking domain. Crustal thinning across the necking domain affects mainly the lower continental crust. The Variscan crust of the Tethys margin is bending downward beneath the Betics, reaching 45 km depth, and terminates abruptly at a major slab tear. The distal domain of the paleomargin cannot be reconstructed, but the migrated section suggests that material has been exhumed through the subduction channel and integrated into the Betic orogen. This supports an origin of the HP-LT Nevado-Filabride units from subducted, hyperextended Variscan crust. According to our profile, the present-day eastern Betics appear to have a much more significant contribution from metamorphic Iberian crust than previously thought.Geophysical Instrument Pool at GFZ-Potsdam - Spanish State Research Agency (SRA) PID2019-109608GB I00/SRA/10.13039/501100011033Spanish Government CGL2015-67130-C2-2-RFEDER/Junta de Andalucia project A-RNM-421-UGR18 RNM104Junta de Andaluci

    The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

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    AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

    Earthquakes and entropy: Characterization of occurrence of earthquakes in southern Spain and Alboran Sea

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    The authors wish to acknowledge IAGPDS and IGN for the availability of the seismic dataset. We are especially grateful to Benito Martin (IAGPDS) for his help and advice with the SEISAN and GMT public programs. This work has been partially supported by the RNM104 and RNM194-Research Groups belonging to Junta de Andalucia (Spain). They also received financial support through Spanish National Project No. PID2019-109608GB-I00 and Junta de Andalucia Project No. A-RNM-421-UGR18.We propose the use of entropy, H, as an indicator of the equilibrium state of a seismically active region (seismic system). The relationship between an increase in H and the occurrence of a great earthquake in a study area can be predicted by acknowledging the irreversible transition of a system. From this point of view, the seismic system evolves from an unstable initial state (due to external stresses) to another, where the stresses have dropped after the earthquake occurred. It is an irreversible transition that entails an increase in entropy. Five seismic episodes were analyzed in the south of the Iberian Peninsula, the Alboran Sea (Mediterranean Sea), and the North of Morocco: two of them of moderate-high magnitude (Al Hoceima, 2004 and 2016) and three of them of moderate-low magnitude (Adra, 1993-1994; Moron, 2007; and Torreperogil, 2012-2013). The results are remarkably in line with the theoretical forecasts; in other words: an earthquake, understood as an irreversible transition, must suppose an increase in entropy.Research Groups belonging to Junta de Andalucia (Spain) RNM104 RNM194Spanish National Project PID2019-109608GB-I00Junta de Andalucia A-RNM-421-UGR1

    Análisis espacio-temporal de series sísmicas : aplicación a las Béticas centrales

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    Reducción altaLa distribución de sismos en una serie esta asociada no solo a un plano principal de fractura, sino a una serie de fallas interconexas entre si, con distintas tendencias espaciales que pueden evolucionar durante el desarrollo de la serie sísmica. para estudiar esta morfología de manera objetiva se han puesto a punto las aplicaciones de tres métodos basados en técnicas estadísticas: análisis de componentes principales espacial (acpe), análisis de componentes principales espacio-temporal (acpt) y método de los tres puntos (mtp). todos ellos determinan a partir de una distribución espacial de hipocentros los planos asociados a las direcciones principal y subsidiarias de la ruptura y en el caso de acpt su evolución en el tiempo. se ha desarrollado asimismo un método para la evaluación de la propagación de los errores en la determinación de los acimutes y buzamientos de estos planos, mediante la construcción de unas "curvas de calibración de errores" a partir de una distribución sintética plana con distintos grados de perturbación aleatoria. los métodos se han aplicado a la serie de superstition hills (california), como prueba, por ser una serie muy estudiada por diversos autores, obteniendose las dos tendencias principales seguidas en el tiempo n30-40e y n45w, con buzamiento en ambos casos de 73 grados, asociadas respectivamente a las fallas de elmore range y de superstition hills. los métodos se han aplicado a dos series ocurridas en las béticas centrales, la de Loja en 1985 y la de Antequera en 1989. en la primera se encuentra una tendencia dominante n60w con buzamiento al ne. la serie de antequera revela dos tendencias dominantes seguidas en el tiempo: una n70e que evolucionó a n60w, dando a la distribución final un aspecto de "v", lo que sugiere la existencia de una barrera geométrica que obligo a la ruptura a cambiar de dirección.Univ. de Granada, Departamento de Física Teórica y del Cosmos. 199

    Inhibition of the NF-κB Signaling Pathway Mediates the Anti-inflammatory Effects of Petrosaspongiolide M

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    Petrosaspongiolide M (PT) is a potent secretory phospholipase A, inhibitor and anti-inflammatory agent. This marine metabolite reduced the production of nitrite, prostaglandin E,, and tumor necrosis factor-alpha in the Mouse air pouch injected with zymosan. These effects were also observed in mouse peritoneal macrophages stimulated with zymosan. Inhibition of these inflammatory mediators was related to reductions in inducible nitric oxide synthase, cyclo-oxygenase-2, and tumor necrosis factor-a expression. Since nuclear factor-kappaB (NF-kappaB) appears to play a central role in the transcriptional regulation of these proteins by macrophages, we investigated the effects of PT on this transcription factor. We found that PT was a potent inhibitor of the NF-kappaB pathway since at 1 muM it strongly decreased NF-kappaB-DNA binding in response to zymosan, in mouse peritoneal macrophages. Our study also indicated that PT could interfere with a key step ill NF-kappaB activation, the phosphorylation of IkappaBalpha, resulting in inhibition Of IkappaBalpha degradation. The control of a wide range of mediators by PT suggests a potentially wide therapeutic spectrum for this marine metabolite in inflammatory conditions

    Study protocol for investigating the clinical performance of an automated blood test for glial fibrillary acidic protein and ubiquitin carboxy-terminal hydrolase L1 blood concentrations in elderly patients with mild traumatic BRAIN Injury and reference values (BRAINI-2 Elderly European study): a prospective multicentre observational study

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    International audienceIntroduction:Two blood brain-derived biomarkers, glial fibrillar acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), can rule out intracranial lesions in patients with mild traumatic brain injury (mTBI) when assessed within the first 12 hours. Most elderly patients were excluded from previous studies due to comorbidities. Biomarker use in elderly population could be affected by increased basal levels. This study will assess the performance of an automated test for measuring serum GFAP and UCH-L1 in elderly patients to predict the absence of intracranial lesions on head CT scans after mTBI, and determine both biomarkers reference values in a non-TBI elderly population. Methods and analysis This is a prospective multicentre observational study on elderly patients (≥65 years) that will be performed in Spain, France and Germany. Two patient groups will be included in two independent substudies. (1) A cohort of 2370 elderly patients (1185<80 years and 1185≥80 years; BRAINI2-ELDERLY DIAGNOSTIC AND PROGNOSTIC STUDY) with mTBI and a brain CT scan that will undergo blood sampling within 12 hours after mTBI. The primary outcome measure is the diagnostic performance of GFAP and UCH-L1 measured using an automated assay for discriminating between patients with positive and negative findings on brain CT scans. Secondary outcome measures include the performance of both biomarkers in predicting early (1 week) and midterm (3 months) neurological status and quality of life after trauma. (2) A cohort of 480 elderly reference participants (BRAINI2-ELDERLY REFERENCE STUDY) in whom reference values for GFAP and UCHL1 will be determined. Ethics and dissemination Ethical approval was obtained from the Institutional Review Boards of Hospital 12 de Octubre in Spain (Re#22/027) and Southeast VI (Clermont Ferrand Hospital) (Re# 22.01782.000095) in France. The study’s results will be presented at scientific meetings and published in peer-review publications. Trial registration number NCT05425251

    Study protocol for investigating the clinical performance of an automated blood test for glial fibrillary acidic protein and ubiquitin carboxy-terminal hydrolase L1 blood concentrations in elderly patients with mild traumatic BRAIN Injury and reference values (BRAINI-2 Elderly European study): a prospective multicentre observational study

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    Introduction Two blood brain-derived biomarkers, glial fibrillar acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), can rule out intracranial lesions in patients with mild traumatic brain injury (mTBI) when assessed within the first 12 hours. Most elderly patients were excluded from previous studies due to comorbidities. Biomarker use in elderly population could be affected by increased basal levels. This study will assess the performance of an automated test for measuring serum GFAP and UCH-L1 in elderly patients to predict the absence of intracranial lesions on head CT scans after mTBI, and determine both biomarkers reference values in a non-TBI elderly population.Methods and analysis This is a prospective multicentre observational study on elderly patients (≥65 years) that will be performed in Spain, France and Germany. Two patient groups will be included in two independent substudies. (1) A cohort of 2370 elderly patients (1185&lt;80 years and 1185≥80 years; BRAINI2-ELDERLY DIAGNOSTIC AND PROGNOSTIC STUDY) with mTBI and a brain CT scan that will undergo blood sampling within 12 hours after mTBI. The primary outcome measure is the diagnostic performance of GFAP and UCH-L1 measured using an automated assay for discriminating between patients with positive and negative findings on brain CT scans. Secondary outcome measures include the performance of both biomarkers in predicting early (1 week) and midterm (3 months) neurological status and quality of life after trauma. (2) A cohort of 480 elderly reference participants (BRAINI2-ELDERLY REFERENCE STUDY) in whom reference values for GFAP and UCHL1 will be determined.Ethics and dissemination Ethical approval was obtained from the Institutional Review Boards of Hospital 12 de Octubre in Spain (Re#22/027) and Southeast VI (Clermont Ferrand Hospital) (Re# 22.01782.000095) in France. The study’s results will be presented at scientific meetings and published in peer-review publications.Trial registration number NCT05425251
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