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Miocene evolution of the External Rif Zone (Morocco): Comparison with similar and lateral southern Mediterranean Tethyan margins
No full textThe Miocene evolution of the External Rif Zone (NW Africa Plate) was determined through multidisciplinary analysis of fourteen successions. The updated stratigraphic framework shows how Miocene sediments rest on the Cretaceous–Paleogene terrains through unconformity surfaces, whereas it rests with sedimentary continuity in two sectors. After recognition of lithofacies and three unconformities located near the Oligocene–Aquitanian, Aquitanian–Burdigalian and Serravallian–Tortonian boundaries, the Miocene sedimentary record was divided into three stratigraphic intervals representing deep to shallow marine deposits as Aquitanian–Burdigalian, Langhian and Upper Serravallian–Missinian. The two oldest unconformites are restricted to the central sector, while the upper one is generalized and probably related to the nappe tectonics registered in all sectors of the External Rif. Data from analysis of tectofacies, petrology, mineralogy, meaning and implications of unconformities, and subsidence indicate that: (i) mass flow deposits (turbidites, slumps, olistostromes) are common in all successions but more frequent during the Lower Miocene; (ii) petrology of the detrital components of the arenites indicates recycled orogen-derived sediments, with quartz coming from erosion of metamorphic rocks of the Atlas orogen and/or the African craton; (iii) mineralogy of mudstones suggests a complex erosional evolution of local emerged areas derived from a mixture of contributions coming from the erosion of Upper Jurassic to Paleogene suites, and especially from kaolinite-rich Albian–Cenomanian to Paleogene successions with absence of a clear unroofing. The conjunction of all these clues reinforces the idea of a synsedimentary tectonics affecting the margin/basin system during the Miocene. A thickness analysis of the studied sedimentary successions allows proposing the evolution of the orogenic front and main depozones (foredeep, bulges, wedge-top and intramontane sub-basins) integrated in a complex foreland system migrating from north to south with the Atlas-Mesetas area acting as foreland during Miocene. The orogenic front moved from the Internal Intrarif to Mesorif and later to Internal Prerif. The main wedge-top basin also migrated from the Internal Intrarif to External Intrarif. The foredeep migrated from the Mesorif to the Internal Prerif, while the main forebulge was located in the External Prerif and a secondary bulge developed in the External Intrarif. Intramontane basins developed behind the orogenic front in relative extensional conditions moving from the Internal Intrarif to External Intrarif. The reconstructed Miocene evolution was inserted into a 2D paleogeographic-geodynamic evolutionary model using GPlates software, and then compared to those reported in other external margins of the western Tethys (Betic Chain, Tunisian Tell, Sicilian Maghrebids and Apennines), revealing important similarities and local differences. © 2024 The Author(s)Ministerio de Educación, Cultura y Deporte, MECD; Freie Universität; Junta de Andalucía; Research Groups and projects of the Generalitat Valenciana; Consejo Superior de Investigaciones Científicas, CSIC; EEZA; Universidad de Alicante; Horizon Therapeutics, (101086497); CTMA-IGA, (RNM-188
¡Las niñas también investigamos! Diseminación de Resultados Liderada por un Grupo de Niñas Investigadoras Chilenas en la “Gira Mundial por la Infancia 2020”
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The communication will describe the process of scientific dissemination led by a team of Chilean girl researchers based on the support of the Think Big Chile project, which, in turn, promotes health and wellness initiatives led by children and young people. This would be reflected in the collective elaboration, between adult and female researchers, of this communication. The methodology, of the preparation of the dissemination of results and their participation as such in the Tour, was qualitative. The research techniques were semi-structured group interviews and international meetings, both remotely via Zoom. As a result of those interviews, it was possible to generate a collective interpretation of the results of the national application of an instrument for measuring participation and other rights, previously created by NNJ during the Think Big Chile study, and the description of their educational experience during the COVID-19 virus pandemic. It is expected to generate an approach to the experience of disseminating the results from the perspective of the participating girls and to present some reflections of the process from the perspective of the adult facilitatorLa comunicación describirá el proceso de diseminación científica liderada por un equipo de niñas investigadoras chilenas al alero del proyecto Think Big Chile, que, a su vez, promueve iniciativas de salud y bienestar dirigidas por niños, niñas y jóvenes (NNJ), lo cual se reflejaría en la elaboración colectiva, entre adulta y niñas investigadoras, de esta comunicación. La metodología, de la preparación de la diseminación de resultados y su participación como tal en la Gira, fue cualitativa. Sus técnicas de investigación fueron entrevistas grupales semiestructuradas y encuentros internacionales, ambos de manera remota vía Zoom. A partir de las entrevistas, se logró generar una interpretación colectiva de los resultados de la aplicación nacional de un instrumento de medición de participación y otros derechos, creado previamente por NNJ durante el estudio Think Big Chile, y la descripción de su experiencia educativa durante la pandemia por el virus COVID-19. Se espera generar un acercamiento a la experiencia de difusión de los resultados desde la perspectiva de las niñas participantes y exponer algunas reflexiones del proceso desde la perspectiva de la facilitadora adulta
Resolución de Rectoría N° 012/2024 crea Subcomité de Bioseguridad de Universidad Autónoma de Chile
No full textLearning-oriented motivation: Examining the impact of teaching practices with motivational potential
No full textThis study compares the predictive ability of nine different types of motivational practices on the motivational orientation toward learning. Given the nature of undergraduate studies, identifying the most predictive motivational variables on learning orientation allows us to focus our efforts on those motivational practices to guide students to deploy their cognitive resources by focusing on learning and not only on obtaining good grades. The study included Chilean university students from health (n = 398) and education (n = 365) programs. A Bayesian multiple regression was carried out in both groups. The results show strong evidence of a specific effect of motivational practices on motivational orientation towards learning. Although the impact on motivational orientation toward learning may vary slightly across different fields of study, the primary predictors consistently are practices that emphasize importance and foster autonomy. The effect of utility-focused motivational practices is observed only within the predictive model for the group of health students. © 2024 Valenzuela et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Therapeutic Approach in Oral Rehabilitation of Patients Diagnosed with Thrombophilia, Protein C Deficiency
No full textThrombophilia is defined as any alteration, either congenital or acquired, which promotes and/or facilitates the presentation of a thrombotic phenomenon. Drug treatment of this condition is to prevent (prophylaxis) other thrombotic event by anticoagulant therapy and hemostasis is affected, taking this great implication in the therapeutic approach in oral rehabilitation, leaning realize treatments with prosthetic structures on implants, teeth or tissue-borne. The aim of this case report is to present therapeutic alternatives in patients diagnosed with thrombophilia with protein C deficiency
Extraosseous Ewing’s Sarcoma in Spinal Epidural Space
No full textExtraosseous Ewing’s sarcoma belongs to the family of neuroectodermal tumors that derive from the neural crest, characteristic of its aggressiveness. Several locations have been described, however, epidural presentation is rare. Prognosis has been improved by new oncological regimens and other therapeutic targets are being studied
Dzyaloshinskii-Moriya bias in a free-standing asymmetric homogeneous nanodisk
No full textAn off-center shift of the magnetic hysteresis loop, usually known as exchange bias, develops in an asymmetric nanodisk due to the Dzyaloshinskii-Moriya (DM) interaction. Results exhibit the onset of bias in a system without material interfaces, originating from the relation between the chirality defined by the DM interaction and the geometry. In addition, programmable magnetization bias by the variation of an external field emerges as a possibility. Our simulations, carried out using Mumax3 code, also yield double hysteresis loops, evidencing a magnetization reversal driven by vortex nucleation and annihilation. Bias in a homogeneous nanodisk and its control seem promising for applications. © 2023Financiamiento Basal para Centros Científicos y Tecnológicos de Excelencia, (AFB220001); Universidad de Santiago de Chile; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1211902, 1220215); Conselho Nacional de Desenvolvimento Científico e Tecnológico, CNPq, (305256/2022, APQ-00648-22); Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNAUniversidad Autónoma de Chil
Gestational hypothyroxinemia induces ASD-like phenotypes in behavior, proinflammatory markers, and glutamatergic protein expression in mouse offspring of both sexes
No full textBackground: The prevalence of autism spectrum disorder (ASD) has significantly risen in the past three decades, prompting researchers to explore the potential contributions of environmental factors during pregnancy to ASD development. One such factor of interest is gestational hypothyroxinemia (HTX), a frequent condition in pregnancy associated with cognitive impairments in the offspring. While retrospective human studies have linked gestational HTX to autistic traits, the cellular and molecular mechanisms underlying the development of ASD-like phenotypes remain poorly understood. This study used a mouse model of gestational HTX to evaluate ASD-like phenotypes in the offspring. Methods: To induce gestational HTX, pregnant mice were treated with 2-mercapto-1-methylimidazole (MMI), a thyroid hormones synthesis inhibitor, in the tap-drinking water from embryonic days (E) 10 to E14. A separate group received MMI along with a daily subcutaneous injection of T4, while the control group received regular tap water during the entire pregnancy. Female and male offspring underwent assessments for repetitive, anxious, and social behaviors from postnatal day (P) 55 to P64. On P65, mice were euthanized for the evaluation of ASD-related inflammatory markers in blood, spleen, and specific brain regions. Additionally, the expression of glutamatergic proteins (NLGN3 and HOMER1) was analyzed in the prefrontal cortex and hippocampus. Results: The HTX-offspring exhibited anxious-like behavior, a subordinate state, and impaired social interactions. Subsequently, both female and male HTX-offspring displayed elevated proinflammatory cytokines in blood, including IL-1β, IL-6, IL-17A, and TNF-α, while only males showed reduced levels of IL-10. The spleen of HTX-offspring of both sexes showed increased Th17/Treg ratio and M1-like macrophages. In the prefrontal cortex and hippocampus of male HTX-offspring, elevated levels of IL-17A and reduced IL-10 were observed, accompanied by increased expression of hippocampal NLGN3 and HOMER1. All these observations were compared to those observed in the Control-offspring. Notably, the supplementation with T4 during the MMI treatment prevents the development of the observed phenotypes. Correlation analysis revealed an association between maternal T4 levels and specific ASD-like outcomes. Discussion: This study validates human observations, demonstrating for the first time that gestational HTX induces ASD-like phenotypes in the offspring, highlighting the need of monitoring thyroid function during pregnancy. Copyright © 2024 González-Madrid, Rangel-Ramírez, Opazo, Méndez, Bohmwald, Bueno, González, Kalergis and Riedel.Universidad de Chile, Uchile, (21202085, PUENTE-2023-18); Universidad de Chile, Uchile; Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT, (1231851, 1240971, 1231905, 11221280, 1191300); Fondo Nacional de Desarrollo Científico y Tecnológico, FONDECYT; Agencia Nacional de Investigación y Desarrollo, ANID, (ICN2021_045); Agencia Nacional de Investigación y Desarrollo, ANIDUniversidad Autónoma de Chil
Wallenberg Sindrome: A Case Report
No full textWallenberg's Syndrome represents 36 % of strokes in the brainstem. It is due to occlusion of the inferior cerebellar artery, affecting structures found in the cerebellum and the lateral part of the medulla oblongata. The main risk factor is atherosclerosis. The case is about a 57-year-old male patient with a history of lacunar infarcts in the cerebellum, type 2 diabetes mellitus, smoking and dyslipidemia. It begins with an intense and sudden occipital headache, without attenuating, concomitantly vertigo, hiccups, nausea, vomiting and paresthesia of lower limbs. At the physical examination, decreased peripheral pulses present Horner's syndrome, hypoesthesia, hypoesthesia in left hemiface, and contralateral hemibody, with ataxia, dysmetria and dysdiadochokinesia. MRI was performed with diffusion with diagnostic Hyperintense image of irregular morphology in the left lateral contour of the medulla oblongata, compatible with ischemic event (Wallenberg syndrome). Antithrombotic treatment and physical therapy was indicated. Patient was evaluated 2 months later showing ample improvement. It is a very specific syndrome, whose clinical manifestation depends on the anatomical region affected and abstracts the clinician from other diagnoses
Effect of Exercise Prior to Sedentary Behavior on Vascular Health Parameters: A Systematic Review and Meta-Analysis of Crossover Trials
No full textBackground: Sedentary behavior has been shown to negatively affect parameters of endothelial function and central hemodynamics, both of which are closely associated with vascular health. Exercise prior to sedentary behavior has demonstrated potential as a preventive strategy to mitigate these detrimental effects. To evaluate the impact of exercise prior to sedentary behavior on vascular health parameters in the adult population, a systematic review and meta-analysis were conducted, synthesizing the available body of knowledge. Methods: A literature search was carried out in 6 databases. For each outcome, standard error and mean difference or standardized mean difference were calculated, as appropriate. An analysis was performed using a random effects model with a 95% confidence interval, using the inverse variance statistical method. Risk of bias assessment was performed using ROB2 and considerations for crossover trials. The quality of evidence was assessed using the GRADE system. Results: Exercise performed prior to prolonged sedentary behavior resulted in increased flow-mediated vasodilation at the first and third hours of sedentary time, compared with the control condition of sedentary behavior without prior exercise [MD: 1.51% (95% CI: 0.57 to 2.45) and MD: 1.36% (95% CI: 0.56 to 2.16), respectively]. Moreover, prior exercise led to increased shear rate at the first and third hours of sedentary time [MD: 7.70 s^−1 (95% CI: 0.79 to 14.61) and MD: 5.21 s^−1 (95% CI: 1.77 to 8.43), respectively]. Furthermore, it increased blood flow at the third hour [SMD: 0.40 (95%CI: 0.07 to 0.72)], compared with the control condition of prolonged sedentary behavior without prior exercise. Regarding hemodynamic parameters, exercise prior to prolonged sedentary behavior decreased mean arterial pressure during the first and third hours of sedentary behavior [MD: -1.94 mmHg (95% CI: -2.77 to -1.11) and MD: -1.90 mmHg (95% CI: -3.27 to -0.53), respectively], and an increase in heart rate during the first hour [MD: 4.38 beats per minute (95%CI: 2.78 to 5.98)] compared with the control condition of prolonged sedentary behavior without prior exercise. Conclusions: The findings of this research suggest that prior exercise may prevent the impairment of vascular health parameters caused by sedentary behavior. However, the quality of the evidence was estimated as moderate. Therefore, further experimental studies and high-quality clinical trials are needed in this field to strengthen the results and conclusions drawn. PROSPERO registration number: CRD42023393686. © The Author(s) 2024.Universidad Autónoma de Chil