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Ligand-free supermolecules : [Pd2@Ge18]4− and [Pd2@Sn18]4− as multiple-bonded Zintl-ion clusters based on Pd@Ge9 and Pd@Sn9 assembled units
No full textPublisher Copyright: © 2024 The Royal Society of Chemistry.Understanding intercluster bonding interactions is important in the rational synthesis of building blocks for molecular materials. Such characteristics have been developed for coinage metal clusters resembling single-, double-, and triple-bonded species, coined as supermolecules. Herein, we extend such an approach for understanding main-group clusters, thus evaluating [Pd2@E18]4− clusters (E = Ge, Sn) involving the fusion of parent spherical aromatic [Pd@E12]2− building units. Our results indicate intercluster bonding provided by contribution from 2P and 1G shells centered at each building motif, leading to an overall bond order of 2.70 and 2.31 for [Pd2@Ge18]4− and [Pd2@Sn18]4−, respectively. In addition, 119Sn-NMR patterns were evaluated to complement the experimental characterization of a single peak owing to the insolution fluxional behavior of [Pd2@Sn18]4− as three peaks owing to the three sets of unique Sn atoms within the structure. Magnetic response properties revealed that spherical aromatic characteristics from parent [Pd@E12]2− building units are retained in the overall [Pd2@E18]4− oblate cluster as two spherical aromatic units. Hence, the notion of superatomic molecules is extended to Zintl-ion clusters, favoring further rationalization for the fabrication of cluster-assembled solids
A retrospective study suggests 55 days of persistence of SARS-CoV-2 during the first wave of the pandemic in Santiago de Chile
No full textPublisher Copyright: © 2024Background: As the COVID-19 pandemic persists, infections continue to surge globally. Presently, the most effective strategies to curb the disease and prevent outbreaks involve fostering immunity, promptly identifying positive cases, and ensuring their timely isolation. Notably, there are instances where the SARS-CoV-2 virus remains infectious even after patients have completed their quarantine. Objective: Understanding viral persistence post-quarantine is crucial as it could account for localized infection outbreaks. Therefore, studying and documenting such instances is vital for shaping future public health policies. Design: This study delves into a unique case of SARS-CoV-2 persistence in a 60-year-old female healthcare worker with a medical history of hypertension and hypothyroidism. The research spans 55 days, marking the duration between her initial and subsequent diagnosis during Chile's first COVID-19 wave, with the analysis conducted using RT-qPCR. Results: Genomic sequencing-based phylogenetic analysis revealed that the SARS-CoV-2 detected in both Nasopharyngeal swab samples (NPSs) was consistent with the 20B clade of the Nextstrain classification, even after a 55-day interval. Conclusion: This research underscores the need for heightened vigilance concerning cases of viral persistence. Such instances, albeit rare, might be pivotal in understanding sporadic infection outbreaks that occur post-quarantine
Proceso de instrucción de la derivada aplicado a estudiantes de Ingeniería Comercial en Chile
No full textPublisher Copyright: © 2024 Universidad Nacional. All rights reserved.[Objective] The objective of this article is to present the results of the implementation of an instructional design for the teaching of the derivative for undergraduate students of Business Engineering in Chile. [Methodology] The participants in the study were ninety students of Applied Business Calculus at a Chilean university. The methodological design, based on the tools of the Ontosemiotic Approach to Mathematical Cognition and Instruction, consider various epistemic configurations in situations-problems concerning tangents, the calculation of derivatives from the rules for derivation, applications of the derivative for the calculation of maxima and minima, and analysis of graphs of functions. In addition, it integrates ICT into various activities. [Results] The results indicate that the instructional proposal for teaching the derivative overcomes some of students’ learning difficulties, as shown in various research studies. In particular, these include the difficulties that Business Engineering students have with the Euclidean conception of the tangent line, the interpretation of the derivative function and its geometric representation, the optimization of economic functions, and the application of the derivative to marginal functions. [Conclusions] It is concluded that the teaching and learning process is effective, in the sense that student learning for a specific engineering career is achieved by instruction that incorporates different interconnected epistemic configurations of the derivative, its different fields of problems, and contextual applications in their profession, together with the use of ICT resources
Ruta humanizada paciente hemato-oncológico adulto en atención unidad quimioterapia ambulatoria Hospital Hernán Henríquez Aravena, Temuco
No full textMagíster en Enfermería de Práctica Avanzada en OncologíaIntroducción: El Hospital Hernán Henríquez Aravena de Temuco, integrante de la macro red extremo sur de la red oncológica nacional, se distingue por su enfoque autogestionado y su compromiso con la prestación de atención de calidad. En este contexto, la humanización se erige como un pilar fundamental de sus directrices estratégicas. Aunque la unidad de quimioterapia ambulatoria adulto comparte este principio en la atención a los pacientes, carece de un protocolo que regule y unifique los criterios de actuación en materia de cuidados humanizados. Objetivo: El presente estudio tiene como propósito diseñar un protocolo destinado a estandarizar el trato y los cuidados humanizados que deben recibir las personas a lo largo de su trayectoria en la unidad de quimioterapia ambulatoria. Metodología: Para identificar y priorizar las causas principales que subyacen a las disparidades en la prestación de atención, se emplearon la técnica de grupo nominal y la matriz decisional. Resultados: Como resultado de este proceso, se ha elaborado un protocolo que establece pautas claras para el trato y los cuidados humanizados, proporcionando así una guía para el equipo de salud en la unidad de quimioterapia ambulatoria. Conclusiones: La implementación de cuidados humanizados se sustenta en tres pilares fundamentales: el perfil del personal, la infraestructura y la organización. En consecuencia, se destaca la imperiosa necesidad de protocolizar estos cuidados, así como el papel crucial que desempeñan las Enfermeras de Práctica Avanzada en su implementación y evaluación, a través del seguimiento de indicadores específicos. Se proyecta la evaluación de estos resultados para la segunda fase de este plan de mejora.|Introduction: The Hernán Henríquez Aravena Hospital in Temuco, a member of the far south macro network of the national oncology network, is distinguished by its self-managed approach and its commitment to the provision of quality care. In this context, humanization is a fundamental pillar of its strategic guidelines. Although the adult outpatient chemotherapy unit shares this principle in patient care, it lacks a protocol that regulates and unifies the criteria for action in terms of humanized care. Objective: The purpose of this study is to design a protocol aimed at standardizing the treatment and humanized care that people should receive throughout their stay in the outpatient chemotherapy unit. Methodology: To identify and prioritize the main causes underlying disparities in the provision of care, the nominal group technique and the decisional matrix were used. Results: As a result of this process, a protocol has been developed that establishes clear guidelines for humanized treatment and care, thus providing guidance for the health care team in the outpatient chemotherapy unit. Conclusions: The implementation of humanized care is supported by three fundamental pillars: staff profile, infrastructure and organization. Consequently, the imperative need to protocolize this care is highlighted, as well as the crucial role played by Advanced Practice Nurses in its implementation and evaluation, through the monitoring of specific indicators. The evaluation of these results is planned for the second phase of this
Exploring biological challenges in building a thinking machine
No full textPublisher Copyright: © 2024 Elsevier B.V.This article presents a transdisciplinary analysis of the challenges in fusing neuroscience concepts with artificial intelligence (AI) to create AI systems inspired by biological cognition. We explore the structural and functional disparities between the neocortex's canonical microcircuits and existing AI models, focusing on architectural differences, learning mechanisms, and energy efficiency. The discussion extends to adapting non-goal-oriented learning and dynamic neuronal connections from biological brains to enhance AI's flexibility and efficiency. This work underscores the potential of neuroscientific insights to revolutionize AI development, advocating for a paradigm shift towards more adaptable and brain-like AI systems. We conclude that there is major room for bioinspiration by focusing on developing architecture, objective functions, and learning rules using a local instead of a global approach
The Reelin receptor ApoER2 is a cargo for the adaptor protein complex AP-4 : Implications for Hereditary Spastic Paraplegia
No full textPublisher Copyright: © 2024 Elsevier LtdAdaptor protein complex 4 (AP-4) is a heterotetrameric complex that promotes export of selected cargo proteins from the trans-Golgi network. Mutations in each of the AP-4 subunits cause a complicated form of Hereditary Spastic Paraplegia (HSP). Herein, we report that ApoER2, a receptor in the Reelin signaling pathway, is a cargo of the AP-4 complex. We identify the motif ISSF/Y within the ApoER2 cytosolic domain as necessary for interaction with the canonical signal-binding pocket of the µ4 (AP4M1) subunit of AP-4. AP4E1- knock-out (KO) HeLa cells and hippocampal neurons from Ap4e1-KO mice display increased co-localization of ApoER2 with Golgi markers. Furthermore, hippocampal neurons from Ap4e1-KO mice and AP4M1-KO human iPSC-derived cortical i3Neurons exhibit reduced ApoER2 protein expression. Analyses of biosynthetic transport of ApoER2 reveal differential post-Golgi trafficking of the receptor, with lower axonal distribution in KO compared to wild-type neurons, indicating a role of AP-4 and the ISSF/Y motif in the axonal localization of ApoER2. Finally, analyses of Reelin signaling in mouse hippocampal and human cortical KO neurons show that AP4 deficiency causes no changes in Reelin-dependent activation of the AKT pathway and only mild changes in Reelin-induced dendritic arborization, but reduces Reelin-induced ERK phosphorylation, CREB activation, and Golgi deployment. This work thus establishes ApoER2 as a novel cargo of the AP-4 complex, suggesting that defects in the trafficking of this receptor and in the Reelin signaling pathway could contribute to the pathogenesis of HSP caused by mutations in AP-4 subunits
Identification of Single-Nucleotide Polymorphisms in Differentially Expressed Genes Favoring Soybean Meal Tolerance in Higher-Growth Zebrafish (Danio rerio)
No full textPublisher Copyright: © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.Genetic variability within the same fish species could confer soybean meal (SBM) tolerance in some individuals, thus favoring growth. This study investigates the single-nucleotide polymorphisms (SNPs) in differentially expressed genes (DEGs) favoring SBM tolerance in higher-growth zebrafish (Danio rerio). In a previous work, nineteen families of zebrafish were fed a fish meal diet (100FM control diet) or SBM-based diets supplemented with saponin (50SBM + 2SPN–experimental diet), from juvenile to adult stages. Individuals were selected from families with a genotype-by-environment interaction higher (170 ± 18 mg) or lower (76 ± 10 mg) weight gain on 50SBM + 2SPN in relation to 100FM. Intestinal transcriptomic analysis using RNA-seq revealed six hundred and sixty-five differentially expressed genes in higher-growth fish fed 50SBM + 2SPN diet. In this work, using these results, 47 SNPs in DEGs were selected. These SNPs were genotyped by Sequenom in 340 zebrafish that were fed with a 50SBM + 2SPN diet or with 100FM diet. Marker-trait analysis revealed 4 SNPs associated with growth in 3 immunity-related genes (aif1l, arid3c, and cst14b.2) in response to the 50SBM + 2SPN diet (p-value < 0.05). Two SNPs belonging to aif1l y arid3c produce a positive (+19 mg) and negative (−26 mg) effect on fish growth, respectively. These SNPs can be used as markers to improve the early selection of tolerant fish to SBM diet or other plant-based diets. These genes can be used as biomarkers to identify SNPs in commercial fish, thus contributing to the aquaculture sustainability
(Dis)connecting rent gap and gentrification in verticalizing cities : The cases of Iquique and Antofagasta, Chile
No full textPublisher Copyright: © 2024 Elsevier LtdThis paper explores the concept of density rent gaps in verticalizing cities, with relation to Peter Marcuse's displacement categories. The study highlights a commonly uncritical relation with the rent gap that both defenders and critics of gentrification usually assume in the literature. Results from a quantitative analysis of a Displacement Index suggest that the largest rent gaps do not always correlate with the highest displacement rates because, in verticalizing cities, the most significant rent gaps come from ‘density rent’ and not necessarily the most expensive new housing. The study focuses on Chile's second-tier towns of Iquique and Antofagasta (seldom seen in the international literature). It uses real estate and population data and fieldwork analysis to fill data voids and caps the rent gap to estimate the amount of land value capture possible to implement to reduce Chile's highly exclusionary housing environment. We believe this analysis helps to conceptually separate the rent gap from gentrification for a more precise urban analysis of vertical cities
Diseñar un sistema contador de camadas de pallets con un sistema de visión artificial en la línea 2 del área de envasado de Cervecería CCU Chile
No full textLa cervecería CCU es una compañía dedica al rubro cervecero, que inicia sus
actividades en Chile en el año 1850 en la región de Valparaíso. Posteriormente,
debido a su alta demanda, se construye una planta en Quilicura en 1981. Esta planta
posee varias líneas de producción, de las cuales, podemos destacar: líneas de
barriles, líneas de latas de aluminio y líneas de botellas retornables o como también
líneas de botellas desechables (One way). Actualmente, las líneas de producción
no son capaces de manejar ni distinguir un número concreto de merma y por ende
de producción, ya que no cuentan con un sistema de conteo de entrada de las
materias primas (latas vacías) que verifiquen lo que se solicita a abastecimiento
para cumplir con la cuota de producción del proceso. Por esto, es que la empresa
CCU se ha visto con un gran problema de mermas que influye en una pérdida
económica en la zona de las líneas de envasado de las áreas de producción.
Con la mirada de un ingeniero industrial, se propone una mejora para la línea N° 2
de la empresa CCU Quilicura, la cual se trata de un diseño de visión artificial (V.A.)
automatizado, el que podrá apoyar con un conteo real de materias primas (latas)
que entran al área de envasado exclusivamente en la línea N° 2. Para cumplir con
este objetivo se ocuparán varias herramientas usadas comúnmente en la ingeniería
para poder gestionar de mejor manera el proceso de producción, con el objetivo de
disminuir las perdidas, lo que se traduce en un beneficio para los trabajadores y la
empresa CCU. Donde se analizará el problema, como también el diseño propuesto
de una manera óptima y con un análisis de viabilidad económica.The CCU brewery is a company dedicated to the beer industry, which began its
activities in Chile in 1850 in the Valparaíso region. Later, due to its high demand, a
plant was built in Quilicura in 1981. This plant has several production lines, of which
we can highlight: barrel lines, aluminum can lines and returnable bottle lines or
disposable bottle lines (One Way). Currently, the production lines are not able to
handle or distinguish a specific number of losses and therefore production, since
they do not have a counting system for the entry of raw materials (empty cans) that
verifies what is requested from supply to meet the production quota of the process.
For this reason, the CCU company has seen a great problem of losses that
influences an economic loss in the area of the packaging lines of the production
areas.
From the perspective of an industrial engineer, an improvement is proposed for line
No. 2 of the CCU Quilicura company, which is an automated artificial vision (A.V.)
design, which will be able to support with an actual count of raw materials (cans) that
enter the packaging area exclusively on line No. 2. To meet this objective, several
tools commonly used in engineering will be used in order to better manage the
production process, with the aim of reducing losses, which translates into a benefit
for the workers and the CCU company. Where the problem will be analyzed, as well
as the proposed design in an optimal way and with an economic feasibility analysis
Self duality in unconventional conformal supersymmetry
No full textPublisher Copyright: © 2024, The Author(s).In this work, we study (anti-)self duality conditions in unconventional conformal supersymmetry. We focus on a theory constructed in a Townsend-MacDowell-Mansouri form for an SU(2, 2|N) gauge connection with matter fields in the adjoint representation. We find bosonic solutions that correspond to analytic gravitational instantons with nontrivial torsion. These configurations can be regarded as the torsional generalization of the Taub-NUT/Bolt-AdS and Eguchi-Hanson metric and they are (anti-)self-dual with respect to a generalized dual operator. We explore their global properties and show that they saturate a BPS bound