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In this study, we synthesized Co2P nanoparticles using a solid-state phosphorization method and evaluated the electrocatalytic response to glucose oxidation reaction (GORs). The influence of synthesis conditions on the particle size, morphology of Co2P species and formation of byproducts is discussed. A lower molar ratio of the phosphorus precursor leads to a decrease in the generation of byproducts. In addition, the calcination temperature and time greatly influence the purity level of the Co2P species and its particle size. Thus, we obtained three pure Co2P nanoparticles with different sizes and morphologies. Significant differences in their electrocatalytic activity against the GOR are observed depending on the size of the particles, being the smaller ones the most efficient. Based on Tafel analysis, a higher catalytic activity was observed for the carbon fibre (CF)/Co2P composite compared to Co2P, which presented a greater onset potential and low response in current density. Tafel slopes close to 120 mV/dec were obtained for both materials, indicating that the mechanism is independent of the type of Co2P-based material used. Finally, the performance of the GCE/CF/Co2P sensor was demonstrated by amperometric measurements, with a sensitivity of 409 µAmM-1cm-2, a linear range between 39.4 µM and 150 µM, and a detection limit of 0.97 µM, analytical characteristics better than those obtained for other cobalt phosphide-based sensors reported in the literature. In addition, the GCE/CF/Co2P sensor shows excellent selectivity and demonstrated to be competitive compared to other Co-based non-enzymatic glucose sensors.

In this work, two commercial extruded filaments for 3D printing obtained from different NatureWorks PLA resins (Ingeo™ Biopolymer 3D850 and Ingeo™ Biopolymer 4043D) were solid-state drawn at varying temperatures and subsequently heat treated by annealing. The aim was to analyze the effect of post-processing of industrial fibers (solid-state drawing and annealing treatment) with varied composition (PLA grades with different contents of D-isomer) on the mechanical performance and thermal stability of the obtained PLA fibers. Morphological, thermal, and mechanical characterizations were performed for the undrawn filaments and drawn fibers, both before and after heat treatment. Drawn fibers presented a fibrillar core–shell structure, and their mechanical properties were greatly improved with respect to undrawn filaments in accordance with their higher crystallinity. The resin with the higher content of D-isomer (4043D) resulted in lower crystallinities with a subsequent decrease in mechanical properties. After heat treatment, drawn fibers exhibited completely different behaviors depending on the PLA resin, with 3D850 fibers being much more stable than 4043D fibers, which underwent molecular orientation upon drawing rather than crystallization. The solid-state drawn fibers obtained herein are comparable to commercial fibers in terms of mechanical properties.

RESUMO Este estudo teve como objetivos identificar estudantes com talento matemático no Ensino Fundamental e no Ensino Médio, no que se refere ao sistema numérico maia e babilônico para o Ensino Fundamental e ao pensamento computacional, com o uso do Scratch, para o Ensino Médio; projetar e implementar um programa de enriquecimento extraescolar com alunos do Ensino Fundamental e do Ensino Médio; estudar a evolução das ideias matemáticas, trabalhadas no programa de enriquecimento extracurricular. O aporte teórico foi baseado no Modelo de Enriquecimento para toda a Escola (School Wide Enrichment Model - SEM). Esse modelo teve origem no Modelo Triádico de Enriquecimento de Renzulli. Os resultados apresentados referem-se às atividades de enriquecimento extracurricular, com numeração babilônica e o sistema numérico maia, e as atividades em ambiente Scratch. Os resultados do estudo mostraram que ambos os grupos de idade foram capazes de abordar as atividades propostas e desenvolveram experiências de aprendizado que lhes deram habilidades para resolver problemas matemáticos, tanto no ambiente a lápis e papel quanto na linguagem de programação Scratch. O grupo de alunos do Ensino Fundamental representou números no sistema maia e babilônico e realizou operações aritméticas; dessa forma, este trabalho os ajudou a compreender o sistema posicional; e os estudantes do Ensino Médio aprenderam a fazer animações de dois personagens (sprites) e aprenderam a programar.

Background: Pulmonary vein stenosis (PVS) is a rare condition in which neointimal proliferation leads to venous and arterial hypertension. Little is known about PVS after heart transplant (HTx) in children. We sought to describe the characteristics and outcomes of children who develop PVS after HTx. Methods: We performed a retrospective review of patients ≤18 years old who underwent HTx at two HTx centers between April 2012 and October 2023. Patients with PVS were identified via database queries. Cardiac diagnosis, PVS location and extent, and outcomes were recorded. Results: Over 11.5 years, 422 patients underwent HTx across both centers. Nineteen patients with PVS (10 male) were identified, 15 with de novo PVS. Sixteen had underlying congenital heart disease (CHD), two with anomalous pulmonary venous return. PVS was diagnosed at a median of 2 months (range 2 weeks to 14 years) after HTx. At time of initial diagnosis, 13 patients had one‐vessel PVS. At final follow‐up, 7/19 (37%) had increases in the number of vessels involved. Six patients underwent surgery, and nine patients had stent or balloon angioplasty. Two patients were treated for pulmonary hypertension following PVS diagnosis. Three patients died from right heart failure secondary to PVS. Conclusions: This is the largest study to describe the characteristics of post‐HTx PVS in children. PVS occurs in 4.5% of HTx, and underlying CHD is a strong risk factor. Multiple vessels can be involved and may require catheter‐based or surgical intervention. Clinicians must be vigilant in monitoring the development of PVS in this population. [ABSTRACT FROM AUTHOR]

This paper analyses the tangible and intangible Yagan heritage contents exhibited by the Museo del Fin del Mundo (MFM, Ushuaia, Tierra del Fuego, Argentina) and presented during its guided tour led by Yagan Community Counsellor Victor Vargas Filgueira. We show how the critical outlook of Fuegian history offered in the latter challenges the traditional past-only fossilized view of the Yagan, building past–present links and helping to overcome biased hegemonic discourses. We also discuss how employing a member of the Yagan Community at the MFM has been an efficient and low-budget strategy that helps to comply with some Goals of the UN 2030 Agenda for Sustainable Development, which are difficult to attain in developing countries. Significant outcomes of this process include: (a) providing a full-time formal job to a member of an Indigenous Community who has been traditionally dispossessed of/in their own territory; (b) acknowledging him as a knowledge holder and valuable member of society; (c) moving the role of Yagan People from subject to agent of the MFM. This process has fostered the dialogue between Yagan voices and academic discourses, challenging traditional Western dichotomies-ecology/economy, natural/cultural heritage, and so forth, and contributing to the discussion of key concepts on sustainability and engagement.

The evaluation of the quality of electric power distribution services in Brazil is regulated and monitored by the National Electric Energy Agency ANEEL, which uses metrics related to the duration frequency of power interruptions that occur in the power utilities’ networks. The methodology applied by the agency to establish financial compensation due to violations of the quality standards does not take into consideration the consumers’ production industry when establishing compensation for the transgression of service quality indicators. This study will analyze a case study of a group of industrial consumers linked to agribusiness in the southern region of Brazil, which have strongly seasonal use of distribution networks and are scattered in large, dispersed areas. Based on the evaluation of the impact of service quality indicators on financial compensation, a regulatory mechanism is proposed in the form of an interruptible tariff duly quantified in the form of a non-linear programming problem to find a discount range for uninterruptible tariffs. The results obtained with the real data for the group of irrigating consumers demonstrate the feasibility regarding the application of the proposed approach, whether due to the discounts offered or even the repercussions of the calculated financial amounts.

En este trabajo se analizan los artefactos producidos por poblaciones indígenas fueguinas expuestos en la exhibición antropológica/arqueológica del Museo del Fin del Mundo, ubicado en la ciudad de Ushuaia (Tierra del Fuego, Argentina), a fin de indagar en su proceso de patrimonialización como objetos museográficos. Para ello, se describe analíticamente dicha exhibición y se analizan: (a) los artefactos expuestos –arqueológicos, etnográficos y contemporáneos– y (b) la información escrita y visual asociada a dichos artefactos. De esta manera, se propone una aproximación a parte de los procesos de formación de la colección expuesta, centrándonos en discutir el proceso de selección y patrimonialización de estos objetos museográficos. Así, se indagan y discuten los contenidos, discursos e imaginarios que transmite el museo acerca del patrimonio cultural de los pueblos originarios fueguinos.

Background Although rare, classic viral myocarditis in the pediatric population is a disease that carries significant morbidity and mortality. Since 2020, myocarditis has been a common component of multisystem inflammatory syndrome in children (MIS‐C) following SARS‐CoV‐2 infection. In 2021, myocarditis related to mRNA COVID‐19 vaccines was recognized as a rare adverse event. This study aims to compare classic, MIS‐C, and COVID‐19 vaccine‐related myocarditis with regard to clinical presentation, course, and outcomes. Methods and Results In this retrospective cohort study, we compared patients aged

Cell migration, a fundamental process in development, wound healing, and immune function, is a common topic in undergraduate cell biology courses. We developed laboratory exercises with an inquiry-based learning (IBL) approach in which cell migration could be examined with the scratch assay, adapted from the primary literature. A narrow scratch was created in a confluent monolayer of cells growing on the bottom of a cell culture dish. Migration into the resultant cell-free zone from both sides of the scratch was measured after one day using the scale bar function of a digital camera. The Chinese hamster ovary cell line was used, but any adherent cell type could be examined. Students used the scratch assay to formulate hypotheses and design experiments in which variables affecting cell migration could be investigated. For example, the effect of cytoskeletal disruption was evaluated by adding the microtubule- and microfilament-disrupting drugs, colcemid and phallacidin, respectively, to the growth medium when the scratch was made. Optimal drug concentration parameters were determined for students to reference. Low drug concentrations inhibited cell migration, while higher concentrations killed the cells. This study demonstrated that the scratch assay is an accessible IBL method for studying cell migration.

Biomedicine requires materials able to respond to specific needs without affecting the organism. Organic–inorganic fibrillar polymeric matrices possess unique properties that may fulfill these needs. In the present study, different topology-controlled poly(ε-caprolactone)-based fibrillar matrices containing glycine betaine at varying concentrations (0.5, 1, and 2% w/v) were prepared via electrospinning. The matrices were used as substrates in calcium carbonate crystallization assays with gas diffusion to obtain a single organic–inorganic hybrid material. The resulting matrices and crystalline material were characterized using spectroscopic, microscopic, and thermogravimetric analyses. The incorporation of glycine betaine into a poly(ε-caprolactone) mesh modified the diameter of the fibers, without affecting the thermal behavior of the matrices. However, the chemical and morphological characteristics of the matrices did influence in vitro inorganic mineralization. The thermogravimetric analysis of the matrices, performed after the mineralization tests, demonstrated the existence of a new organic–inorganic hybrid material with unique properties, which is discussed in the present study.

In the rural regions of southern Brazil, electricity is largely directed to irrigation activities on rice crops at restricted periods of the year. Typically, customers in these regions are called “irrigators”, and have some characteristics different from loads in urban centers, such as high demand levels and sharp load variations. These characteristics can result in problems of excessive loading on distribution grids at certain times of the day, generating concerns for the power utilities in relation to the security of the electrical system, energy supply to customers, and the integrity of electrical equipment. An alternative to avoid or mitigate these possible problems may be the application of a demand management model to irrigator customers. In this context, a load shifting strategy can be inserted to reduce demand in more critical periods and move it to intervals with lower load on the power grid. In this context, this article presents a demand-side management methodology in distribution systems located in rural areas, employing the load shifting strategy for irrigator customers. The methodology proposed in this paper is not an entirely novel approach, but one specifically developed for the context of irrigator customers, a subject little studied in the literature. The load management model proposed by this study is segmented into three hierarchical levels. The first level is the identification of the electrical characteristics of the distribution systems, the second level is the power flow analysis of the distribution networks, and the third and last level consists in the application of load shifting to the irrigator customers of these electrical systems. The load shifting strategy is modeled by a linear programming algorithm and is only applied to irrigator customers in situations of excessive loading on power grid. The case studies were conducted on three distribution systems of a power utility, with more than 150 irrigator customers. The DSM model based on the load shifting strategy reduced the maximum demand and daily load variations on the three rural feeders evaluated. The proposed changes in load patterns can ensure the continuity of electric power supply service in future even with the high concentration of load on distribution networks, benefiting customers and power utilities.

In the last decade, we have witnessed an upsurge in nuclei-based studies, particularly coupled with next-generation sequencing. Such studies aim at understanding the molecular states that exist in heterogeneous cell populations by applying increasingly more affordable sequencing approaches, in addition to optimized methodologies developed to isolate and select nuclei. Although these powerful new methods promise unprecedented insights, it is important to understand and critically consider the associated challenges. Here, we provide a comprehensive overview of the rise of nuclei-based studies and elaborate on their advantages and disadvantages, with a specific focus on their utility for transcriptomic sequencing analyses. Improved designs and appropriate use of the various experimental strategies will result in acquiring biologically accurate and meaningful information.

Background: Children awaiting heart transplant (Tx) have a high risk of death due to donor organ scarcity. Historically, ventricular assist devices (VADs) reduced waitlist mortality, prompting increased VAD use. We sought to determine whether the VAD survival benefit persists in the current era. Methods: Using the Scientific Registry of Transplant Recipients, we identified patients listed for Tx between 3/22/2016 and 9/1/2020. We compared characteristics of VAD and non‐VAD groups at Tx listing. Cox proportional hazards models were used to identify risk factors for 1‐year waitlist mortality. Results: Among 5054 patients, 764 (15%) had a VAD at Tx listing. The VAD group was older with more mechanical ventilation and renal impairment. Unadjusted waitlist mortality was similar between groups; the curves crossed ~90 days after listing (p =.55). In multivariable analysis, infant age (HR 2.77, 95%CI 2.13–3.60), Black race (HR 1.57, 95%CI 1.31–1.88), congenital heart disease (HR 1.23, 95%CI 1.04–1.46), renal impairment (HR 2.67, 95%CI 2.19–3.26), inotropes (HR 1.28, 95%CI 1.09–1.52), and mechanical ventilation (HR 2.23, 95%CI 1.84–2.70) were associated with 1‐year waitlist mortality. VADs were not associated with mortality in the first 90 waitlist days but were protective for those waiting ≥90 days (HR 0.43, 95%CI 0.26–0.71). Conclusions: In the current era, VADs reduce waitlist mortality, but only for those waitlisted ≥90 days. The differential effect by race, size, and VAD type is less clear. These findings suggest that Tx listing without VAD may be reasonable if a short waitlist time is anticipated, but VADs may benefit those expected to wait >90 days. [ABSTRACT FROM AUTHOR]

En este trabajo indagaremos en los diferentes ritmos que tuvo la adopción de cultura material occidental por parte de la sociedad Yagán de Tierra de Fuego desde fines del siglo XIX hasta mediados del siglo XX. Para ello, centraremos el análisis en un corpus de 428 fotografías etnográficas de este pueblo originario, obtenidas entre 1881 y 1987 en Tierra del Fuego, a fin de analizar de manera diacrónica la adopción desigual de cultura material occidental, específicamente respecto de la vestimenta y los adornos. De esta manera, esperamos discutir los distintos procesos desarrollados respecto de esta cultura material a partir del contacto con los europeos: adopción plena, adopción parcial (ciclaje), reciclaje y resiliencia. Así, encontramos que los yaganes fueron agentes activos de su propio cambio cultural, que tuvo distintos ritmos vinculados a procesos de negociación y resiliencia, que permitieron la supervivencia física y cultural de este Pueblo Originario.

En este artículo presentaremos un panorama sistemático acerca las condiciones de accesibilidad a las fotografías etnográficas de indígenas patagónico-fueguinos, a fin de evaluar y discutir las posibilidades reales de ejercer el derecho de acceso público a la información que aportan estos documentos. Primero, indagaremos en el nuevo lugar que ocupa la fotografía en la investigación en ciencias sociales y en el rol que cumplen los archivos en la custodia de estos documentos. Luego, analizaremos de manera rigurosa la localización y las condiciones de accesibilidad a las 1465 fotografías relevadas en un total de 13 archivos, tanto públicos como privados y tanto centrales como locales y extranjeros. Para ello, analizaremos: a) la cantidad de fotografías conservadas en cada archivo, b) la existencia de datos contextuales como autor, fecha, lugar y epígrafe, c) las condiciones de preservación, d) el orden, clasificación y descripción, e) la consulta y el acceso y f) la difusión de cada archivo. Finalmente, indagaremos en cómo estos problemas de accesibilidad al patrimonio fotográfico indígena obstaculizan una valoración real de la historia, la memoria y la identidad.

Birk-Barel intellectual disability is an imprinting syndrome due to maternally-only transmitted mutations of KCNK9/TASK3. Here authors are using a heterozygous deletion of the active maternal Kcnk9 allele to model the disease and show phenotypic rescue by HDAC inhibition.