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Alzheimer’s disease (AD) is a neurodegenerative pathology, which is characterized by progressive and irreversible cognitive impairment. Most of the neuronal perturbations described in AD can be associated with soluble amyloid– β oligomers (SO-Aβ). There is a large amount of evidence demonstrating the neuroprotective effect of Nicotine neurotransmission in AD, mainly through nicotinic acetylcholine receptor (nAChR) activation and antiapoptotic PI3K/Akt/Bcl–2 pathway signaling. Using HPLC and GC/MS, we isolated and characterized two alkaloids obtained from C. scoparius, Lupanine (Lup), and 17– oxo-sparteine (17– ox), and examined their neuroprotective properties in a cellular model of SO-Aβ toxicity. Our results showed that Lup and 17– ox (both at 0.03μM) prevented SO-Aβ-induced toxicity in PC12 cells (Lup: 64±7%; 17– ox: 57±6%). Similar results were seen in hippocampal neurons where these alkaloids prevented SO-Aβ neurotoxicity (Lup: 57±2%; 17– ox: 52±3%) and increased the frequency of spontaneous calcium transients (Lup: 60±4%; 17– Ox: 40±3%), suggesting an enhancing effect on neural network activity and synaptic activity potentiation. All of the neuroprotective effects elicited by both alkaloids were completely blocked by α-bungarotoxin. Additionally, we observed that the presence of both Lup and 17– ox increased Akt phosphorylation levels (52±4% and 35±7%, respectively) in cells treated with SO-Aβ (3 h). Taken together, our results suggest that the activation of nAChR by Lup and 17– ox induces neuroprotection in different cellular models, and appears to be an interesting target for the development of new pharmacological tools and strategies against AD.

Society faces multiple challenges in this millennium and education should promote skills that allow students and teachers to face them. Students will have to be prepared for jobs that have not yet been created, for technologies that have not yet been invented, to solve problems that have no yet been anticipated. As educators will be a shared responsibility to take advantage of the opportunities and find solutions. In this context, international organizations linked to educational change are rethinking the role of the current education. One initiative is the creation of frameworks to promote and develop skills for the 21st century which are defined as a set of skills necessary to interact in today’s world, mainly in study and employment, where the management of technology is crucial. In Chile, initiatives in this area are being foreshadowed and it is necessary to define a reference framework that complement this process. The aims of this paper is to propose a frame of reference of skills for the 21st century that synthesizes the diversity of referents to have a useful referent to guide educational innovation processes in our Latin American context. Based on a comparative methodology, it was applied a descriptive-comparative analysis of frameworks formulated by international organizations that promote these skills. Theoretical analysis results show concordance in five categories: Cognitive, Social, Emotional, Information and Communication Technologies (ICT), and Curricular Contents for the 21st century. With this background, we are able to present a referential framework maintaining the five categories, and adding 38 essential skills.

One of the problems investors often face is deciding on the stocks to include in an investment portfolio. Hence, this article seeks to select investment portfolios considering the 30 leading companies listed on the New York Stock Exchange (NYSE) of the Dow Jones Index. Portfolio selection in this index is carried out by generating a previous ranking of the shares with a novel approach that analyzes their performance using a multiple criteria hierarchical process (MCHP). The current research allows the evaluation of shares and optimizing a portfolio, while developing a procedure that supports a decision-making process for organizations or practitioners to invest in the stock market. The results of analyzing the NYSE generated a portfolio that can be used for interested investors. The main contribution of the application of MCHP and Markowitz model is related to the possibility of replicating the developed procedure to select portfolios in other stock markets.

In order to reduce greenhouse gas emissions, countries worldwide are transforming their energy systems with higher shares of renewable energy and smart technologies for demand response. Microgrids play an essential role in the transformation of electric grids to smart grids. However, renewable sources present new challenges, particularly those of high variability, which creates uncertainties in the supply side that can affect the security of electricity access at affordable prices. This paper proposes a novel Stackelberg stochastic model to account for different sources of uncertainty. The Stackelberg model considers microgrids as leaders (upper-level problem) with uncertainty regarding the availability of wind and solar sources and electricity prices. Availability of renewable sources is modeled via chance constraints, which allows assessing the risk of microgrids over-committing supply levels. Uncertainty in electricity prices is modeled via a set of demand scenarios with a given probability distribution. The lower-level problem of the Stackelberg problem considers an electricity dispatch problem for each demand scenario. The proposed model allows measuring the strategic actions of microgrids when facing different types of uncertainties and how the smart grid should adapt to guarantee that demand levels are supplied. The results show the effectiveness of the proposed method. We find that microgrids risk levels above 30% do not correlate with further benefits, such as reduced electricity prices. We also identified that in average, depending on the social cost of carbon and demand level, microgrids can cover their own demand and supply 15% of the electricity demand in the grid.

Electrical impedance tomography (EIT) is a technology that estimates the electrical properties of a body or a cross section. Its main advantages are its non-invasiveness, low cost and operation free of radiation. The estimation of the conductivity field leads to low resolution images compared with other technologies, and high computational cost. However, in many applications the target information lies in a low intrinsic dimensionality of the conductivity field. The estimation of this low-dimensional information is addressed in this work. It proposes optimization-based and data-driven approaches for estimating this low-dimensional information. The accuracy of the results obtained with these approaches depends on modelling and experimental conditions. Optimization approaches are sensitive to model discretization, type of cost function and searching algorithms. Data-driven methods are sensitive to the assumed model structure and the data set used for parameter estimation. The system configuration and experimental conditions, such as number of electrodes and signal-to-noise ratio (SNR), also have an impact on the results. In order to illustrate the effects of all these factors, the position estimation of a circular anomaly is addressed. Optimization methods based on weighted error cost functions and derivate-free optimization algorithms provided the best results. Data-driven approaches based on linear models provided, in this case, good estimates, but the use of nonlinear models enhanced the estimation accuracy. The results obtained by optimization-based algorithms were less sensitive to experimental conditions, such as number of electrodes and SNR, than data-driven approaches. Position estimation mean squared errors for simulation and experimental conditions were more than twice for the optimization-based approaches compared with the data-driven ones. The experimental position estimation mean squared error of the data-driven models using a 16-electrode setup was less than 0.05% of the tomograph radius value. These results demonstrate that the proposed approaches can estimate an object's position accurately based on EIT measurements if enough process information is available for training or modelling. Since they do not require complex calculations it is possible to use them in real-time applications without requiring high-performance computers.

Two 3D-learning environments in SecondLife and OpenSim have been developed as part of a grant project called TYMMI -Technology and Pedagogical Models in Immersive Worlds- funded by the National Fund for Scientific and Technological Development (FONDECYT) in Chile. The main objective is to strengthen the professional performance of pre-service teachers (bachelor students), by simulating teaching practices and virtual learning opportunities where the community members join a meeting or class, share and interact in the complex process of assimilation teaching skills. Preliminary results are related to the design of two immersive simulation platforms and to develop a conceptual and technological model for teaching in Immersive Worlds. In this context, the authors created an ACTI-PLAN that allows pre-service teachers to act in two areas: cataloging resources and educational planning. Also, in this virtual space there is an architecture that supports pedagogical proposal that includes classrooms for Mathematic and Language for elementary education.

Evidencia empírica muestra que la renovación urbana en altura además de re-estratificar socioeconómicamente los barrios, establece una oferta de movilidad y configuración territorial que puede ser ventajosa para un determinado sujeto y no para otro en términos de restricciones económicas, culturales e incluso físicas de movilidad y transporte. Estas condiciones son conceptualizadas en el “capital de movilidad”, entendido como la capacidad de los sujetos de ser móviles en el territorio a partir de capacidades de acceso, competencia y apropiación. El objetivo es comprender de qué forma las condiciones del capital de movilidad determinan un aprovechamiento socialmente diferenciado del territorio expresado en la movilidad cotidiana de distintos habitantes del pericentro de Santiago. Se realiza un análisis cuantitativo de la Encuesta Panel de Barrios 2 (2016) proporcionada por el Proyecto FONDECYT Regular 1151287, en el que participan los autores, analizando comparativamente tres unidades de estudio en el pericentro de Santiago de Chile. Los resultados desmitifican algunos de los supuestos de eficiencia asociados a la verticalización en donde las decisiones de movilidad de nuevos residentes de departamentos se moldean en dimensiones de libertad y mayores opciones, no así para antiguos residentes de casa, que presentan restricciones físicas y limitados recursos para ejercer la movilidad; es decir, se encuentran “confinados” espacialmente.

The high sensitivity Compton and Rayleigh X-ray scattering signals can be used to gain valuable information on the chemical composition of various matrices, by exploiting the ratio of those signals as a function of the effective atomic number (Zeff). Neither total reflection X-ray fluorescence (TXRF) nor the effect of the experimental setup, including sample preparation, X-ray excitation source selection, and band deconvolution procedure, has been assessed in this kind of approach. Here, a Compton/Rayleigh ratio and Zeff-based TXRF method was set up and tested as an analytical tool for milk samples differentiation. The method was developed using a 90° scattering angle and assessed using different X-ray excitation sources: a molybdenum tube (Mo Kα 17.5 KeV) and a tungsten tube (W Lα 8.5 KeV and W-Brems 35 KeV). The evaluation of independent Compton and Rayleigh signals was performed by non-Gaussian and Gaussian curve resolution methods, and both height and area-based calculations were evaluated. Different sample preparation conditions were assessed. By using 11 standard materials, a calibration curve for Compton/Rayleigh ratio versus Zeff was established. The method was tested to determine the Zeff of milk samples, which enabled its use as a parameter to differentiate them. Good precisions were obtained with the Mo excitation source and the area-based calculations, which allowed to differentiate undiluted milk samples by species, treatment, and fat content according to their Compton/Rayleigh ratio. This simple and rapid method has the potential to be used for the differentiation of various types of samples, including liquids, solids, and aerosols.

Environmental pollution including mutagens from wastewater effluents and discontinuity by man-made barriers are considered typical anthropogenic pressures on microevolutionary processes that are responsible for the loss of biodiversity in aquatic ecosystems. Here, we tested for the effects of wastewater treatment plants (WWTPs), weirs and other stressors on the invertebrate species Gammarus pulex at the population genetic level combining evolutionary ecotoxicology, body burden analysis and testing for exposure to mutagens. Exposure to chemical pollution alone and in combination with the presence of weirs resulted in a depression of allelic richness in native G. pulex populations. Our results suggest that the input of a mutagenic effluent from a WWTP resulted in a strong increase in private alleles over the affected populations. In addition, the presence of weirs along the river disrupted the migration across the river and thus the gene flow between G. pulex upstream and downstream. This study provides strong evidence that the assessment of genetic variation including private alleles together with the contamination of mutagenic and nonmutagenic chemical pollution offers new insights into the regulation of genetic population structure and highlights the relevance of emerging anthropogenic pressures at the genetic level.

Mitogen-activated protein kinase kinase 3 (MKK3) is a dual threonine/tyrosine protein kinase that regulates inflammation, proliferation and apoptosis through specific phosphorylation and activation of the p38 mitogen-activated protein kinase. However, the role of MKK3 beyond p38-signaling remains elusive. Recently, we reported a protein–protein interaction (PPI) network of cancer-associated genes, termed OncoPPi, as a resource for the scientific community to generate new biological models. Analysis of the OncoPPi connectivity identified MKK3 as one of the major hub proteins in the network. Here, we show that MKK3 interacts with a large number of proteins critical for cell growth and metabolism, including the major oncogenic driver MYC. Multiple complementary approaches were used to demonstrate the direct interaction of MKK3 with MYC in vitro and in vivo. Computational modeling and experimental studies mapped the interaction interface to the MYC helix-loop-helix domain and a novel 15-residue MYC-binding motif in MKK3 (MBM). The MBM in MKK3 is distinct from the known binding sites for p38 or upstream kinases. Functionally, MKK3 stabilized MYC protein, enhanced its transcriptional activity and increased expression of MYC-regulated genes. The defined MBM peptide mimicked the MKK3 effect in promoting MYC activity. Together, the exploration of OncoPPi led to a new biological model in which MKK3 operates by two distinct mechanisms in cellular regulation through its phosphorylation of p38 and its activation of MYC through PPI.

La formación de docentes competentes en el uso de las Tecnologías de Información y Comunicación (TIC), tanto a nivel de usuario avanzado como en su utilización pedagógica que implica la planificación, implementación y evaluación de actividades de enseñanza-aprendizaje, es un desafío que las instituciones formadoras están obligadas a abordar en el corto plazo para dar cumplimiento a las exigencias impuestas por el Ministerio de Educación (MINEDUC) en los Estándares Pedagógicos, Disciplinarios y Estándares TIC. Esta intervención fue realizada a una población de 30 estudiantes de tercer semestre de la carrera de Pedagogía en Ciencias de una Universidad Regional de Investigación, cuyo objetivo fue “Evaluar la apropiación de Habilidades TIC en estudiantes de Pedagogía en Ciencias de una Universidad Regional de Investigación a través de la implementación y evaluación de la enseñanza utilizando materiales didácticos multimediales soportados en una plataforma virtual”. Para ello se diseñó un set de materiales que se trabajó con los/las estudiantes a través de la Plataforma Virtual ARCO en la asignatura de Computación y que apuntó al desarrollo de las habilidades TIC evaluadas por la Prueba Inicia TIC en Ambiente Pedagógico, que aplica el MINEDUC CHILE a los/las egresados de pedagogía cada año.

The financial market has been transformed by FinTech platforms, which offer innovative products and services. FinTech platforms use a combination of technologies to digitalize processes and introduce new business models with unique characteristics. The benefits of FinTech initiatives are not limited to boosting the economic development of emerging economies; they also have a transformative impact on society and stakeholders. The transformative impact enables the democratization of digital services, making them accessible to marginalized groups that the traditional financial banking system has excluded. Our study theorizes how FinTech organizational capabilities (digital technologies, digital infrastructures, and talented employees) and FinTech ecosystem conditions (competitors, regulations, digital gender gaps, and institutional gaps) impact inclusion, transparency, and market expansion inspired by transformative entrepreneurship. We tested it through a multilevel analysis using data from 333 worldwide large FinTech platforms combined with secondary data at the country level. Results provide insights into how digital infrastructure, a skilled workforce, and closing the gaps for disadvantaged groups are crucial determinant factors for increasing FinTech impacts in emerging economies. Several implications for entrepreneurs, society, and policymakers emerge as a call for fostering digital societies and FinTech industry in emerging economies.

A theory of sedimentation-consolidation evolved in the last decades of the 20th century and is accepted today by researchers worldwide. This theory provides a reliable method of thickener design, simulation and control. However, a process model, simple or sophisticated, empirical or phenomenological, is useful only if it is possible to determine, in an objective way, its experimental parameters. Although it is important for a mineral processing plant to perform periodical laboratory test to determine thickening parameters, and adjust the operation in this way, laboratory tests not always represent the behavior of the material in a thickener. Research workers at the University of Concepción developed new instrumentation, algorithms and software to determine the material properties of the thickener feed, such as settling velocity of the suspension and the compressibility of the sediment produced. Work was made in a major Chilean copper mineral processing plant to test the new instrumentation. In this paper, the auditing of one molybdenum thickener and a tailings thickener are presented using the two new online instrument.

Structural Health Monitoring (SHM) aims at detecting, localizing, and characterizing damages in civil, mechanical, and aerospatial structures, which are hardly detectable in visual inspections. The collection, analysis, and visualization of data captured by sensors installed on these structures can be strongly supported by modern techniques of Data Science. In particular, the visualization of these data provides valuable help to experts on structural health and decision makers on preventive and corrective maintenance. Unfortunately, existing systems of data visualization still demand those stakeholders for a high level of software programming skills to take full advantage of visual and interactive exploration of data that sensors capture and output. This work introduces a model-driven approach to develop data visualization in the domain of structural health monitoring, in particular, of bridges. This approach is based on the definition of a Domain Specific Language (DSL) that describes the main concepts of an infrastructure of sensors typically used in SHM, along with common graphics and visual alternatives of data visualization. This DSL is instantiated by a modeling language, composed of a metamodel, a visual representation of concepts, and a set of model-to-text transformation rules. In this way, non-programmers can implement their own data visualization from a graphical and intuitive design, by automatically generating the corresponding code. This approach was implemented in a modeling and code-generation tool, called Vis4bridge, whose usability and output were successfully evaluated through the development of tasks and case studies.

Polyphenols are bioactive substances that participate in the prevention of chronic illnesses. High content has been described in Berberis microphylla G. Forst (calafate), a wild berry extensively distributed in Chilean–Argentine Patagonia. We evaluated its beneficial effect through the study of mouse plasma metabolome changes after chronic consumption of this fruit. Characterized calafate extract was administered in water, for four months, to a group of mice fed with a high-fat diet and compared with a control diet. Metabolome changes were studied using UHPLC-DAD-QTOF-based untargeted metabolomics. The study was complemented by the analysis of protein biomarkers determined using Luminex technology, and quantification of OH radicals by electron paramagnetic resonance spectroscopy. Thirteen features were identified with a maximum annotation level-A, revealing an increase in succinic acid, activation of tricarboxylic acid and reduction of carnitine accumulation. Changes in plasma biomarkers were related to inflammation and cardiovascular disease, with changes in thrombomodulin (−24%), adiponectin (+68%), sE-selectin (−34%), sICAM-1 (−24%) and proMMP-9 (−31%) levels. The production of OH radicals in plasma was reduced after calafate intake (−17%), especially for the group fed with a high-fat diet. These changes could be associated with protection against atherosclerosis due to calafate consumption, which is discussed from a holistic and integrative point of view.

Implementing nationally determined contributions is more challenging for developing countries given potential economic consequences. Chile, a developing economy, is committed to reaching carbon neutrality by 2050. To do so, Chile announced multiple mitigation strategies such as phasing out coal by 2040, peaking emissions by 2025, and developing renewable energies. Fortunately, Chile holds a prominent renewable potential, standing out for solar, but it also has a significant challenge decarbonizing an economy that heavily relies on fossil fuels. The contribution of this paper is twofold. First, the first country-level disaggregated version of GCAM Latin America (GCAM-LA) was developed, where all South American countries are modeled as an independent energy-economy region. This model includes Chile as a separated region and incorporates interactions among the energy, water, agriculture and land use, economy, and climate systems. Second, different decarbonization strategies to reach carbon neutrality by 2050 were obtained, considering technology availability and high renewable energy potential. Results indicate that carbon neutrality is feasible when enforcing different combinations of the current Chilean mitigation strategies, even delaying coal phase-out by five years and failure of developing advanced solar technologies. If some policies are not fully implemented, such as delaying coal phase-out by five years or failure of developing advanced solar technologies, carbon neutrality can be achieved by incurring in a higher capital cost in the power sector. Moreover, decarbonization is mainly driven by high electrification levels in the final demand sector, reaching 53.7%–62.9% of the total consumption. However, such levels of electrification are reduced, particularly in the transport sector, when Chile relies on negative emissions from the land use and forestry sector.

Objetivo: En el contexto de una discusión, aún abierta, en torno al concepto de ciudad creativa, el presente artículo contrasta discursivas globales con apreciaciones locales de personas consideradas creativas, identificando características urbanas que atraen y generan arraigo, y otras que producen desafección e incomodidad. Metodología: El caso de estudio fue el Área Metropolitana de Concepción (AMC), Chile, realizando entrevistas a personas consideradas creativas; los entrevistados fueron seleccionados mediante técnica de bola de nieve, y el universo muestral se acotó bajo la lógica de saturación. Finalmente, la información obtenida se sistematizó con el software de Análisis de Contenido, T-Lab.8.1. Conclusiones: Los resultados se contrastaron con un estado del arte y discursivas académicas globales, evidenciando consensos, disensos y jerarquías, develando el necesario y local ajuste de una planificación y diseño urbano, en pos de una política de competitividad urbana basada en la fijación y atracción de talento creativo, máxime, de sistemas urbanos intermedios se trata. Originalidad: Estudiar la capacidad de atracción-retención que ejercen las urbes intermedias para con los grupos creativos, con una óptica centrada en las personas y sus experiencias, es poco habitual, pese a que resulta fundamental en un escenario de competencia global por atraer el talento y capital humano avanzado.

Ixodid ticks (Acari:Ixodidae) are essential vectors of tick-borne diseases in Japan. In this study, we characterized the population genetic structure and inferred genetic divergence in two widespread and abundant ixodid species, Ixodes ovatus and Haemaphysalis flava. Our hypothesis was that genetic divergence would be high in I. ovatus because of the low mobility of their small rodent hosts of immature I. ovatus would limit their gene flow compared to more mobile avian hosts of immature H. flava. We collected 320 adult I. ovatus from 29 locations and 223 adult H. flava from 17 locations across Niigata Prefecture, Japan, and investigated their genetic structure using DNA sequences from fragments of two mitochondrial gene regions, cox1 and the 16S rRNA gene. For I. ovatus, pairwise FST and analysis of molecular variance (AMOVA) analyses of cox1 and 16S sequences indicated significant genetic variation among populations, whereas both markers showed non-significant genetic variation among locations for H. flava. A cox1 gene tree and haplotype network revealed three genetic groups of I. ovatus. One of these groups consisted of haplotypes distributed at lower altitudes (251–471 m.a.s.l.). The cox1 sequences of I. ovatus from Japan clustered separately from I. ovatus sequences reported from China, suggesting the potential for cryptic species in Japan. Our results support our hypothesis and suggest that the host preference of ticks at the immature stage may influence the genetic structure of the ticks. This information may be important for understanding the tick-host interactions in the field to better understand the tick-borne disease transmission and in designing an effective tick control program.

El dominio de la tecnología es fundamental para los estudiantes de pedagogía para proponer estrategias metodológicas, didácticas y evaluativas que les permita responder adecuadamente a las demandas del sistema educativo actual. Esta investigación se enfoca desde una perspectiva cuantitativa, con aportes cualitativos, a través de un diseño no experimental descriptivo, a conocer cuál es el nivel de adquisición de las competencias tecnológicas (TIC) de los estudiantes de la Facultad de Educación de la Universidad Católica de la Santísima Concepción (UCSC) en cinco dimensiones relacionadas con el uso e implementación en contextos personales y pedagógicos. La muestra se constituyó de manera aleatoria por 681 estudiantes pertenecientes a seis especialidades de las cohortes 2007, 2009 y 2011 de: pedagogía en educación general básica, educación de párvulo, educación diferencial, pedagogía media en lenguaje y comunicación, pedagogía media en inglés y pedagogía media en biología y ciencias naturales. Los principales resultados indican que los estudiantes poseen un nivel adecuado de competencias TIC requeridas por el Gobierno de Chile; sin embargo, las dimensiones “pedagógica” y “gestión del conocimiento” son las que presentan mayores debilidades. Además, las percepciones de los estudiantes se enfocan a resaltar la necesidad de una formación con mayor apoyo de tecnologías, tanto en la aplicación como en su integración curricular.

Videogames have taken an important role on children and adolescents through the years and gradually took a significant gap in education, leaving out its playful look at leisure. Particularly in Chile, thanks to the integration of Information and Communication Technologies (ICT), several tools like didactic presentation programs or mobile apps facilitate the teaching and learning process of a second language like English. The aim of this research is to describe the design of an educative videogame and to describe the validation process of the Word-y contents which are associated to learning vocabulary in English. The design has been developed using the incremental prototype model' using the free version of Construct2 software. As projections, the future work implies improve the first prototype applying a content survey to 30 English teachers and users.