379 research outputs found
Implicit and implicit-explicit Lagrange-projection finite volume schemes exactly well-balanced for 1D shallow water system
In this paper we consider the Lagrange-Projection technique in the framework of finite volume schemes applied to the shallow water system. We shall consider two versions of the scheme for the Lagrangian step: one fully implicit and one implicit-explicit, based on how the geometric source term is treated. First and second order well-balanced versions of the schemes are presented, in which the water at rest solutions are preserved. This allows to obtain efficient numerical schemes in low Froude number regimes, as the usual CFL restriction driven by the acoustic waves is avoided.This work is partially supported by projects RTI2018-096064-B-C21 and RTI2018-096064-B-C22 funded by MCIN/AEI/10.13039/501100011033 and “ERDF A way of making Europe”, projects P18-RT-3163 of Junta de Andalucía and UMA18-FEDERJA-161 of Junta de Andalucía-FEDER-University of Málaga. C. Caballero-Cárdenas is supported by the grant FPI2019/087773 funded by MCIN/AEI/10.13039/501100011033 and “ESF Investing in your future”. // Funding for open access charge: Universidad de Málaga/CBUA
Efficacy of a self-applied online program to promote resilience and coping skills in university students in four Spanish-speaking countries: study protocol for a randomized controlled trial
Background:
There is evidence of a high prevalence of depression and anxiety in university students. Therefore, college time is a key period where prevention of mental disorders through interventions that promote resilience and mental health can be relevant. Currently, there are interventions available, but these are insufficient for those who need them. Online interventions are tools that can facilitate global accessibility and are easy for young people to use. CORE (Cultivating Our Resilience) is a self-administered online program, based on Ryff’s psychological well-being model, to promote resilience and coping skills in university students at risk of developing symptoms of depression or anxiety. The objective is to evaluate the effectiveness of this intervention protocol in comparison with an active control condition targeting healthy lifestyle, and a waiting list control condition. The study will be conducted in four populations of Spanish-speaking university students (Spain, Argentina, Colombia, and Mexico).
Methods:
The study design is a randomized controlled trial (RCT). At least 324 university students will be randomly assigned to three conditions: 1) CORE, a 6-week training program to improve resilience; 2) HLP, a 6-week training to promote a healthy lifestyle; and 3) WL, waiting list control condition. The primary outcome measure will be the Connor-Davidson resilience scale. Additionally, measures of anxiety, depression, quality of life and socio-demographic variables (age, sex, incomes, marital status, among others) will be collected. Participants will be evaluated at pre-treatment, after each module, 6 weeks after allocation, and at 3-month follow-up. Intention-to-treat and per-protocol analyses will be performed.
Discussion:
The results of this study will contribute to research on Internet-administered interventions and the implementation of a protocol that includes a series of components designed to improve resilience and coping skills, increase psychological well-being, and prevent depression and anxiety disorders in Spanish-speaking university students. In addition, avenues will be opened up for new research on the effectiveness of these interventions focused on the prevention and promotion of mental health in Spanish-speaking countries
Biomass accumulation and population dynamics of a flooded forest in the Magdalena Basin (Colombia)
Few studies in Colombia have quantified population dynamics on private conservation lands, making it difficult to know whether passive restoration (secondary succession) is a good option to increase forest biomass. We analyzed three permanent plots (0.3 ha) in the Reserva El Paujil (Middle Magdalena Valley, Colombia), in secondary forests, after 8-9 y. We tested whether population changes and aboveground biomass accumulation should be higher in secondary flooded forests than in terra firme forests. We found that mortality rates (7.98/y ± 4.50 DE) were higher than recruitment rates (5.89/y ± 5.29 SD), generating a mean negative change (-2.09/y ± 4.36 SD). However, the growth of surviving individuals was high (0.028 ± 0.019 SD), causing a positive rate of biomass accumulation (3.33 ton/y/ha ± 5.15 SD). This rate was much higher than in terra firme forests in the area (0.10 ton/y/ha ± 1.90 SD), which was associated with soil fertility. The most dominant species with high biomass accumulation was Anacardium excelsum. In contrast, the highest increase in mortality was observed for pioneer species (i.e., Cecropia membranacea and C. peltata), Bauhinia picta, and Guadua angustifolia (which also showed the highest recruitment). Overall, establishing a biological reserve has allowed the growth of large trees, generating carbon stocks equivalent to those from active ecological restoration processes
Involvement of the PI3K/AKT Intracellular Signaling Pathway in the AntiCancer Activity of Hydroxytyrosol, a Polyphenol from Olea europaea, in Hematological Cells and Implication of HSP60 Levels in Its Anti-Inflammatory Activity
Hydroxytyrosol (HT), the main representative of polyphenols of olive oil, has been described as one of the most powerful natural antioxidants, also showing anti-inflammatory, antimicrobial, cardioprotective and anticancer activity in different type of cancers, but has been little studied in hematological neoplasms. The objective of this work was to evaluate the anticancer potential of HT in acute human leukemia T cells (Jurkat and HL60) and the anti-inflammatory potential in murine macrophages (Raw264.7). For this, cytotoxicity tests were performed for HT, showing IC50 values, at 24 h, for Jurkat, HL60 and Raw264.7 cells, of 27.3 mu g center dot mL(-1), 109.8 mu g center dot mL(-1) and 45.7 mu g center dot mL(-1), respectively. At the same time, HT caused cell arrest in G(0)/G(1) phase in both Jurkat and HL60 cells by increasing G(0)/G(1) phase and significantly decreasing S phase. Apoptosis and cell cycle assays revealed an antiproliferative effect of HT, decreasing the percentage of dividing cells and increasing apoptosis. Furthermore, HT inhibited the PI3K signaling pathway and, consequently, the MAPK pathway was activated. Inflammation tests revealed that HT acts as an anti-inflammatory agent, reducing NO levels in Raw264.7 cells previously stimulated by lipopolysaccharide (LPS). These processes were confirmed by the changes in the expression of the main markers of inflammation and cancer. In conclusion, HT has an anticancer and anti-inflammatory effect in the cell lines studied, which were Raw264.7, Jurkat, and HL60, and could be used as a natural drug in the treatment of liquid cancers, leukemias, myelomas and lymphomas.General Secretariat of Universities, Research and Technology of the Ministry of Economy, Innovation, Science and Employment of the Government of the Junta de Andalucia, Spain BIO-15
Análisis participativo de servicios ecosistémicos en un área protegida del bosque seco tropical (bs-T), Colombia
The state of degradation faced by tropical dry forest ecosystems, in different geographical scales, prioritizes their conservation. In this study, a participatory and multicriteria analysis of ecosystem services -ES- associated with current coverages in the tropical dry forest life zone in a protected area, was performed. The ES were spatialized on a local scale, to project management guidelines, and were prioritized and characterized through interviews with key stakeholders. For the approach to the ecosystem functioning, indicators of processes and ecosystem structure were established based on information of soils, flora, fauna and drivers of change. It was found that the most important ES’s are agricultural production and drinking water supply. The ecosystem functioning was low and very low in agricultural systems; low and medium in livestock systems, and high and very high in natural systems. It is recommended to implement sustainable and participatory conservation strategies.El estado de degradación que enfrentan los ecosistemas de bosque seco tropical (bs-T) en diferentes escalas geográficas es razón para priorizar su conservación. En este estudio se hizo un análisis participativo y multicriterio de servicios ecosistémicos (SE) asociados a coberturas presentes en la zona de vida de bs-T en un área protegida. Los SE fueron espacializados a una escala local para proyectar pautas de manejo, los cuales se priorizaron y caracterizaron mediante entrevistas a actores clave. Para la aproximación al funcionamiento del ecosistema se establecieron indicadores de procesos y estructura ecosistémica basados en información de suelos, vegetación, fauna e impulsores de cambio. Se encontró que los SE de mayor importancia son la producción agropecuaria y el suministro de agua potable. El funcionamiento del ecosistema resultó bajo y muy bajo en sistemas agrícolas; bajo y medio en sistemas pecuarios; y alto y muy alto en sistemas naturales. Se recomienda poner en funcionamiento estrategias de conservación sostenibles y participativas
Carbapenem resistance in Enterobacterales bloodstream infections among children with cancer or post-haematopoietic stem cell transplant: a retrospective cohort study
Background
Risk factors for carbapenem resistance in Enterobacterales bloodstream infections among children with cancer or post-HSCT have not been thoroughly explored.
Methods
All children with cancer or post-HSCT who developed Enterobacterales bloodstream infections in two cancer referral centres in major Colombian cities between 2012 and 2021 were retrospectively examined. When the infection episode occurred, carbapenem resistance mechanisms were evaluated according to the available methods. Data were divided in a training set (80%) and a test set (20%). Three internally validated carbapenem-resistant Enterobacterales (CRE) prediction models were created: a multivariate logistic regression model, and two data mining techniques. Model performances were evaluated by calculating the average of the AUC, sensitivity, specificity and predictive values.
Results
A total of 285 Enterobacterales bloodstream infection episodes (229 carbapenem susceptible and 56 carbapenem resistant) occurred [median (IQR) age, 9 (3.5–14) years; 57% male]. The risk of CRE was 2.1 times higher when the infection was caused by Klebsiella spp. and 5.8 times higher when a carbapenem had been used for ≥3 days in the previous month. A model including these two predictive variables had a discriminatory performance of 77% in predicting carbapenem resistance. The model had a specificity of 97% and a negative predictive value of 81%, with low sensitivity and positive predictive value.
Conclusions
Even in settings with high CRE prevalence, these two variables can help early identification of patients in whom CRE-active agents are unnecessary and highlight the importance of strengthening antibiotic stewardship strategies directed at preventing carbapenem overuse.Q1Q1Los factores de riesgo de resistencia a los carbapenémicos en las infecciones del torrente sanguíneo por Enterobacterales entre niños con cáncer o después de un TCMH no se han explorado a fondo.
Métodos
Se examinaron retrospectivamente todos los niños con cáncer o post-TCMH que desarrollaron infecciones del torrente sanguíneo por Enterobacterales en dos centros de referencia de cáncer en las principales ciudades de Colombia entre 2012 y 2021. Cuando ocurrió el episodio de infección, se evaluaron los mecanismos de resistencia a los carbapenémicos según los métodos disponibles. Los datos se dividieron en un conjunto de entrenamiento (80%) y un conjunto de prueba (20%). Se crearon tres modelos de predicción de Enterobacterales resistentes a carbapenémicos (CRE) validados internamente: un modelo de regresión logística multivariante y dos técnicas de minería de datos. El rendimiento del modelo se evaluó calculando el promedio del AUC, la sensibilidad, la especificidad y los valores predictivos.
Resultados
Se produjeron un total de 285 episodios de infección del torrente sanguíneo por Enterobacterales (229 susceptibles a carbapenémicos y 56 resistentes a carbapenémicos) [mediana de edad (RIQ), 9 (3,5 a 14) años; 57% hombres]. El riesgo de CRE fue 2,1 veces mayor cuando la infección fue causada por Klebsiella spp. y 5,8 veces mayor cuando se había utilizado un carbapenem durante ≥3 días en el mes anterior. Un modelo que incluía estas dos variables predictivas tuvo un rendimiento discriminatorio del 77% en la predicción de la resistencia a los carbapenémicos. El modelo tuvo una especificidad del 97% y un valor predictivo negativo del 81%, con baja sensibilidad y valor predictivo positivo.
Conclusiones
Incluso en entornos con una alta prevalencia de CRE, estas dos variables pueden ayudar a la identificación temprana de pacientes en quienes los agentes activos de CRE son innecesarios y resaltar la importancia de fortalecer las estrategias de administración de antibióticos dirigidas a prevenir el uso excesivo de carbapenémicos.N/AS
Caracterización inmunológica de un grupo familiar colombiano con infección por SARS-CoV-2
Introduction: Immunological markers have been described during COVID-19 and persist after recovery. These immune markers are associated with clinical features among SARSCoV-2 infected individuals. Nevertheless, studies reporting a comprehensive analysis of the immune changes occurring during SARS-CoV-2 infection are still limited.Objective: To evaluate the production of proinflammatory cytokines, the antibody response, and the phenotype and function of NK cells and T cells in a Colombian family cluster with SARS-CoV-2 infection.Materials and methods: Proinflammatory cytokines were evaluated by RT-PCR and ELISA. The frequency, phenotype, and function of NK cells (cocultures with K562 cells) and T-cells (stimulated with spike/RdRp peptides) were assessed by flow cytometry. Anti-SARS-CoV-2 antibodies were determined using indirect immunofluorescence and plaque reduction neutralization assay.Results: During COVID-19, we observed a high proinflammatory-cytokine production and a reduced CD56bright-NK cell and cytotoxic response. Compared with healthy controls, infected individuals had a higher frequency of dysfunctional CD8+ T cells CD38+HLA-DR-. During the acute phase, CD8+ T cells stimulated with viral peptides exhibited a monofunctional response characterized by high IL-10 production. However, during recovery, we observed a bifunctional response characterized by the co-expression of CD107a and granzyme B or perforin.Conclusion: Although the proinflammatory response is a hallmark of SARS-CoV-2 infection, other phenotypic and functional alterations in NK cells and CD8+ T cells couldbe associated with the outcome of COVID-19. However, additional studies are required to understand these alterations and to guide future immunotherapy strategies.Introducción. Se han descrito diferentes marcadores inmunológicos durante la COVID-19, los cuales persisten incluso después de la convalecencia y se asocian con los estadios clínicos de la infección. Sin embargo, aún son pocos los estudios orientados al análisis exhaustivo de las alteraciones del sistema inmunológico en el curso de la infección.Objetivo. Evaluar la producción de citocinas proinflamatorias, la reacción de anticuerpos, y el fenotipo y la función de las células NK y los linfocitos T en una familia colombiana con infección por SARS-CoV-2.Materiales y métodos. Se evaluaron las citocinas proinflamatorias mediante RT-PCR y ELISA; la frecuencia, el fenotipo y la función de las células NK (en cocultivos con células K562) y linfocitos T CD8+ (estimulados con péptidos spike/RdRp) mediante citometría de flujo, y los anticuerpos anti-SARS-CoV-2, mediante inmunofluorescencia indirecta y prueba de neutralización por reducción de placa.Resultados. Durante la COVID-19 hubo una producción elevada de citocinas proinflamatorias, con disminución de las células NK CD56bright y reacción citotóxica. Comparados con los controles sanos, los individuos infectados presentaron con gran frecuencia linfocitos T CD8+ disfuncionales CD38+HLA-DR-. Además, en los linfocitos T CD8+ estimulados con péptidos virales, predominó una reacción monofuncional con gran producción de IL-10 durante la fase aguda y una reacción bifuncional caracterizada por la coexpresión de CD107a y granzima B o perforina durante la convalecencia.Conclusión. Aunque la reacción inflamatoria caracteriza la infección por SARS-CoV-2, hay otras alteraciones fenotípicas y funcionales en células NK y linfocitos T CD8+ que podrían asociarse con la progresión de la infección. Se requieren estudios adicionales para entender estas alteraciones y guiar futuras estrategias de inmunoterapia
BOOTES-IR: Near IR follow-up GRB observations by a robotic system
“BOOTES-IR” is the extension of the BOOTES experiment, which
operates in Southern Spain since 1998, to the near IR (NIR). The goal is to follow up the early stage of the gamma ray burst (GRB) afterglow emission in the NIR, alike BOOTES does already at optical wavelengths. The scientific case that drives the BOOTES-IR performance is the study of GRBs with the support of spacecraft like INTEGRAL, SWIFT and GLAST. Given that the afterglow emission in both, the NIR and the optical, in the instances immediately following a GRB, is extremely bright (reached V = 8.9 in one case), it should be possible to detect this prompt emission at NIR wavelengths too. The combined observations by BOOTES-IR and
BOOTES-1 and BOOTES-2 will allow for real time identification of trustworthy candidates to have a high redshift (z > 5). It is expected that, few minutes after
a GRB, the IR magnitudes be H ∼ 7–10, hence very high quality spectra can be obtained for objects as far as z = 10 by larger instruments
¿Qué nos dejó la pandemia?. Retos y aprendizajes para la educación superior
Experiencias, vivencias y reflexiones sobre la realidad actual de la educación universitaria forman parte de esta publicación. La transición de una educación mayoritariamente presencial a una educación de emergencia a distancia con la proyección de un futuro de un sistema híbrido, exige nuevos retos. Los cambios no pueden ser solo de forma: la crisis provocada por la pandemia demanda transformaciones en varios aspectos: la modalidad, el ritmo, los roles de estudiantes y docentes, la metodología, las formas de evaluar, las características del aprendizaje síncrono u asíncrono, el uso de la tecnología. Todo esto implica la construcción colectiva de una nueva realidad educativa orientada a la formación de una ciudadanía activa, con herramientas personales y profesionales para mejorar la realidad social actual
Co-creating FabLab La Campana: Empowering a Marginalised Community in the North of Mexico
FabLabs are a celebrated approach to formal and informal learning through making with digital fabrication tools. This paper discusses the co-creation of a FabLab with a marginalised community in Monterrey, Mexico. One of the main challenges in establishing these Makerspaces is in sustaining the activities and community engagement on an ongoing basis. In responding to this challenge, this process focused on the empowerment of community members to make the changes they desire, either for themselves or their community. Beyond skills for making and playful engagement in STEAM learning, makerspaces also facilitate the building of networks and partnerships, and the development of social competencies and soft skills, that are often overlooked in the process of empowerment and social mobility. Primary insights from the co-creation process of the La Campana FabLab are reported here. A Mexican higher education institution with a strong social responsibility agenda facilitated the process, securing funds and connecting project partners, locally and globally. Framing the cocreation of the FabLab with the partners was and is an ongoing process. Key factors included the donation of a safe space and tools for the community to host and run the FabLab. Establishing the role of the FabLab in the community from the participants’ point-of-view and committing to regular ongoing educational dialogue was important in forming an equitable partnership between institutions and community. Beyond the physical space, equipment and educational activities, a community architecture intervention demonstrated the large-scale impact digital fabrication could have in creating spaces shaped by and for the community
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