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Post-processing, and particularly the dry electropolishing process, is essential for improving the surface quality of 3D-printed Ti6Al4V samples, with specific emphasis on reducing roughness over extended polishing times while preserving mechanical properties. Reducing surface roughness enhances the reliability of hardness measurements and improves the consistency of elastic modulus measurements, as prolonged polishing time stabilizes the full width at half maximum values, thereby minimizing variability due to uniaxial indentation. This stability is crucial for maintaining the structural integrity and uniformity of mechanical properties, facilitating better performance and reliability in biomedical applications. Additionally, under service-like working conditions, solid electrolyte particles undergo dehydration due to the Joule effect, introducing a dynamic aspect to the system as the particle structure degrades with thermal cycling. EDX cross-sectional analysis reveals that TiO2 informs the particle’s surface, with an oxygen-to-titanium ratio that confirms the oxide’s composition. This TiO2 oxide layer demonstrates the progressive surface oxidation occurring under the post-processing process, further modifying the particle’s surface chemistry. This dual effect of roughness reduction and controlled surface chemistry highlights the role of dry electropolishing in enhancing the functional lifespan and mechanical reliability of Ti6Al4V components.

Background: The COVID-19 pandemic has highlighted a correlation between cardiac complications and elevated cardiac biomarkers, which are linked to poorer clinical outcomes. Objective: This study aims to determine the clinical impact of cardiac biomarkers in COVID-19 patients in Latin America. Subjects and methods: The CARDIO COVID 19-20 Registry is a multicenter observational study across 44 hospitals in Latin America and the Caribbean. It included hospitalized COVID-19 patients (n = 476) who underwent troponin, natriuretic peptide, and D-dimer tests. Patients were grouped based on the number of positive biomarkers. Results: Among the 476 patients tested, 139 had one positive biomarker (Group C), 190 had two (Group B), 118 had three (Group A), and 29 had none (Group D). A directly proportional relationship was observed between the number of positive biomarkers and the incidence of decompensated heart failure. Similarly, there was a proportional relationship between the number of positive biomarkers and increased mortality. In Group B, patients with elevated troponin and natriuretic peptide and those with elevated troponin and D-dimer had 1.4 and 1.5 times higher mortality, respectively, than those with elevated natriuretic peptide and D-dimer. Conclusions: In Latin American COVID-19 patients, a higher number of positive cardiac biomarkers is associated with increased cardiovascular complications and mortality. These findings suggest that cardiac biomarkers should be utilized to guide acute-phase treatment strategies.

Precision edge preparation techniques for cemented carbides enable optimization of the geometry of tools’ cutting edges. These techniques are frequently used in high-stress environments, resulting in substantial improvements in tools’ cutting performance. This investigation examined the impact and evolution of cutting edge parameters and resulting surface finishes as a function of dry-electropolishing time on an end-mill. Findings demonstrate enlargement of the cutting edge radius, a decrease in surface roughness, and the mitigation of defects induced during previous manufacturing stages (i.e., smashed ceramic particles, burrs, chipping, etc.). Additionally, a direct correlation between dry-electropolishing time and primary cutting edges’ micro-geometry parameters has been established.

Background: Socioeconomic factors contribute to a more severe impact of COVID-19 in Latin American and Caribbean (LA&C) countries than in developed countries. Patients with a severe or critical illness can develop respiratory and cardiovascular complications. Objective: To describe a LA&C population with COVID-19 to provide information related to this disease, in-hospital cardiovascular complications, and in-hospital mortality. Methods: The CARDIO COVID-19–20 Registry is an observational, multicenter, prospective, and hospital-based registry of patients with confirmed COVID-19 infection that required in-hospital treatment in LA&C. Enrollment of patients started on May 01, 2020, and ended on June 30, 2021. Results: The CARDIO COVID-19–20 Registry included 3260 patients from 44 institutions of 14 LA&C countries. 63.2% patients were male and median age was 61.0 years old. Most common comorbidities were overweight/obesity (49.7%), hypertension (49.0%), and diabetes mellitus (26.7%). Most frequent cardiovascular complications during hospitalization or reported at discharge were cardiac arrhythmia (9.1%), decompensated heart failure (8.5%), and pulmonary embolism (3.9%). The number of patients admitted to the Intensive Care Unit (ICU) was 1745 (53.5%), and median length of their stay at the ICU was 10.0 days. Support required in ICU included invasive mechanical ventilation (34.2%), vasopressors (27.6%), inotropics (10.3%), and vasodilators (3.7%). Rehospitalization after 30-day post discharge was 7.3%. In-hospital mortality and 30-day post discharge were 25.5% and 2.6%, respectively. Conclusions: According to our findings, more than half of the LA&C population with COVID-19 assessed required management in ICU, with higher requirement of invasive mechanical ventilation and vasoactive support, resulting in a high in-hospital mortality and a considerable high 30-day post discharge rehospitalization and mortality.

El sector minero mexicano representa una de las cadenas más productivas del país y el auge de esta actividad ha impulsado la manufactura a nivel nacional. Se identifican cuatro periodos de producción en la historia de este ramo: 1) extracción de metales preciosos; 2) desarrollo e implementación de nuevos métodos de extracción, procesamiento y fundición de metales; 3) la industrialización minera a través de la explotación de minerales no metálicos; y 4) la apertura de la economía nacional con la presencia de corporaciones trasnacionales. Este artículo se enfoca en la última etapa (1970-2020), donde se localiza la aplicación de sistemas científico-tecnológicos que dan paso a la creación de patentes. El objetivo es realizar un análisis sobre las tendencias en la concesión de éstas en la minería mexicana con el fin de conocer el nivel de su desarrollo tecnológico a nivel nacional. Se realizó un análisis patentométrico a partir de la información contenida en la base de patentes Lens, que considera indicadores temporales, de autoridad, de sectorización y de clasificación. Los resultados generales muestran la dinámica de producción actual en la concesión de patentes y la presencia de actores que contribuyen al desarrollo de esta labor.

Abstract Background The dynamics of the actomyosin machinery is at the core of many important biological processes. Several relevant cellular responses such as the rhythmic compression of the cell cortex are governed, at a mesoscopic level, by the nonlinear interaction between actin monomers, actin crosslinkers, and myosin motors. Coarse-grained models are an optimal tool to study actomyosin systems, since they can include processes that occur at long time and space scales, while maintaining the most relevant features of the molecular interactions. Results Here, we present a coarse-grained model of a two-dimensional actomyosin cortex, adjacent to a three-dimensional cytoplasm. Our simplified model incorporates only well-characterized interactions between actin monomers, actin crosslinkers and myosin, and it is able to reproduce many of the most important aspects of actin filament and actomyosin network formation, such as dynamics of polymerization and depolymerization, treadmilling, network formation, and the autonomous oscillatory dynamics of actomyosin. Conclusions We believe that the present model can be used to study the in vivo response of actomyosin networks to changes in key parameters of the system, such as alterations in the attachment of actin filaments to the cell cortex.

Cell proliferation and differentiation show a remarkable inverse relationship. The temporal coupling between cell cycle withdrawal and differentiation of stem cells (SCs) is crucial for epithelial tissue growth, homeostasis and regeneration. Proliferation vs. differentiation SC decisions are often controlled by the surrounding microenvironment, of which the basement membrane (BM; a specialized form of extracellular matrix surrounding cells and tissues), is one of its main constituents. Years of research have shown that integrin-mediated SC-BM interactions regulate many aspects of SC biology, including the proliferation-to-differentiation switch. However, these studies have also demonstrated that the SC responses to interactions with the BM are extremely diverse and depend on the cell type and state and on the repertoire of BM components and integrins involved. Here, we show that eliminating integrins from the follicle stem cells (FSCs) of the Drosophila ovary and their undifferentiated progeny increases their proliferation capacity. This results in an excess of various differentiated follicle cell types, demonstrating that cell fate determination can occur in the absence of integrins. Because these phenotypes are similar to those found in ovaries with decreased laminin levels, our results point to a role for the integrin-mediated cell-BM interactions in the control of epithelial cell division and subsequent differentiation. Finally, we show that integrins regulate proliferation by restraining the activity of the Notch/Delta pathway during early oogenesis. Our work increases our knowledge of the effects of cell-BM interactions in different SC types and should help improve our understanding of the biology of SCs and exploit their therapeutic potential.

Environmental, social, and economic sustainability patterns interact in various dimensions of an urban environment. Exacerbated population growth triggers an emphasis on better resource management strategies addressing the balance of supply and demand over food, energy, and water sectors while considering social and economic development. Promoting sustainable development goals requires governance structures and functions within and across the food, energy, and water sectors, specifically due to polycentric urban development. This study emphasizes food security via an urban agriculture network in the greater Miami metropolitan area, encompassing the three counties of Palm-Beach, Broward, and Miami-Dade. Given the existing governance structure, we quantified several sustainability indices for clustering analysis to agglomerate urban agricultural sites (UASs) and to help identify the priority of clusters in terms of vulnerability or risk level according to their priority index in multicriteria decision-making. The cases of eight clusters were selected for the visualization of the UASs ranked by multicriteria decision-making based on scenarios prioritized for governance under the impacts of climate change, social equity, and economic development. The role of governance structure was highlighted for signifying the incentive programs to enhance the overall sustainability performance of UASs in an urban food–energy–water nexus.

Multiple tissue perfusion markers are described to guide therapy in critically ill pediatric patients undergoing congenital heart surgery. Given the advantages of capillary refill time, our goal is to determine its predictive capacity for mortality and postoperative extracorporeal oxygenation requirements in congenital heart surgery and compare it to serum lactate. We conducted a prospective cohort observational study in a single high-complexity university hospital. Serum lactate and capillary refill time were measured at five predetermined time points: preoperative, immediate postoperative, 6, 12, and 24 h after the surgery. Prolonged immediate postoperative, 6 h, and 12 h capillary refill time measurements turned out to be independent risk factors for both outcomes. The capillary refill time area under the curve ranged between 0.70 and 0.80, while the serum lactate resulted between 0.79 and 0.92 for both outcomes. Both tissue perfusion markers resulted in mortality and extracorporeal oxygenation requirement predictors. Given the advantages of capillary refill time over serum lactate, a monitoring strategy including these two perfusion markers should be considered for congenital heart surgeries.

Adhesion to the extracellular matrix (ECM) is required for normal epithelial cell survival. Disruption of this interaction leads to a specific type of apoptosis known as anoikis. Yet, there are physiological and pathological situations in which cells not connected to the ECM are protected from anoikis, such as during cell migration or metastasis. The main receptors transmitting signals from the ECM are members of the integrin family. However, although integrin-mediated cell-ECM anchorage has been long recognized as crucial for epithelial cell survival, the in vivo significance of this interaction remains to be weighed. In this work, we have used the Drosophila wing imaginal disc epithelium to analyze the importance of integrins as survival factors during epithelia morphogenesis. We show that reducing integrin expression in the wing disc induces caspase-dependent cell death and basal extrusion of the dead cells. In this case, anoikis is mediated by the activation of the JNK pathway, which in turn triggers expression of the proapoptotic protein Hid. In addition, our results strongly suggest that, during wing disc morphogenesis, the EGFR pathway protects cells undergoing cell shape changes upon ECM detachment from anoikis. Furthermore, we show that oncogenic activation of the EGFR/Ras pathway in integrin mutant cells rescues them from apoptosis while promoting their extrusion from the epithelium. Altogether, our results support the idea that integrins promote cell survival during normal tissue morphogenesis and prevent the extrusion of transformed cells.

Autonomous oscillatory dynamics are ubiquitous at every level in Biology. At the cellular level, one of the most relevant and well characterized examples of periodic behavior is the cyclic assembly and disassembly of actomyosin networks. In Drosophila, these oscillations induce the robust contraction and expansion of individual cells required for correct dorsal closure, while in the follicular epithelium that surrounds the germline, periodic contractions of the basal actomyosin network are required for proper elongation of the egg chamber. While some studies suggest that actomyosin oscillations are driven by upstream signaling or mechanochemical features, we have recently proposed that they arise as a systems property from the competition between two well characterized features of the actomyosin machinery: 1) cooperative assembly of actin networks mediated by Actin crosslinker proteins and 2) tension-induced disassembly of actin networks mediated by myosin motors. Here, we perform experiments in amnioserosa and in the follicle cells of drosophila and simulations using a coarse-grained model of the actomyosin cortex to characterize the properties of the oscillations and how they depend on different features of the system. We also compare model and experiments to study the dynamics of actomyosin flows and the effect of mechanical coupling between cells in the tissue. In conclusion, our model is a powerful tool to study key features of actomyosin oscillations, from the effect of the individual components to network properties and finally supra-cellular organization of the oscillations at the tissue level.

En el presente artículo se describe una metodología que permite tener un acercamiento a modelos probabilísticos alternativos para el análisis de supervivencia, con censura por la derecha, distintos a los que usualmente se estudian (distribución: exponencial, gamma, Weibull y log-normal), ya que es posible que los datos no se ajusten siempre con suficiente precisión por las distribuciones existentes. La metodología utilizada permite mayor flexibilidad de modelar observaciones extremas, ubicadas generalmente en la cola derecha de la distribución de los datos, lo cual admite que algunos eventos aún tengan la probabilidad de ocurrir, lo que no sucede con los modelos tradicionales y el estimador de Kaplan-Meier, el cual estima para los tiempos más prolongados, probabilidades de supervivencia aproximadamente iguales a cero. Para mostrar la utilidad de la propuesta metodológica, se consideró una aplicación con datos reales que relaciona tiempos de supervivencia de pacientes con cáncer de colon.

Forces generated by the actomyosin cytoskeleton are key contributors to many morphogenetic processes. The actomyosin cytoskeleton organises in different types of networks depending on intracellular signals and on cell-cell and cell-extracellular matrix (ECM) interactions. However, actomyosin networks are not static and transitions between them have been proposed to drive morphogenesis. Still, little is known about the mechanisms that regulate the dynamics of actomyosin networks during morphogenesis. This work uses the Drosophila follicular epithelium, real-time imaging, laser ablation and quantitative analysis to study the role of integrins on the regulation of basal actomyosin networks organisation and dynamics and the potential contribution of this role to cell shape. We find that elimination of integrins from follicle cells impairs F-actin recruitment to basal medial actomyosin stress fibers. The available F-actin redistributes to the so-called whip-like structures, present at tricellular junctions, and into a new type of actin-rich protrusions that emanate from the basal cortex and project towards the medial region. These F-actin protrusions are dynamic and changes in total protrusion area correlate with periodic cycles of basal myosin accumulation and constriction pulses of the cell membrane. Finally, we find that follicle cells lacking integrin function show increased membrane tension and reduced basal surface. Furthermore, the actin-rich protrusions are responsible for these phenotypes as their elimination in integrin mutant follicle cells rescues both tension and basal surface defects. We thus propose that the role of integrins as regulators of stress fibers plays a key role on controlling epithelial cell shape, as integrin disruption promotes reorganisation into other types of actomyosin networks, in a manner that interferes with proper expansion of epithelial basal surfaces.

Cell arrangement in the plane of epithelia is well studied, but its three-dimensional packing is largely unknown. Here the authors model curved epithelia and predict that cells adopt a geometrical shape they call “scutoid”, resulting in different apical and basal neighbours, and confirm the presence of scutoids in curved tissues.

La interactividad es fundamental en el desarrollo de un servicio público televisivo adaptado a la era digital y a las nuevas demandas de los consumidores. Las redes sociales se han revelado como herramientas esenciales para fomentar la participación online y transformar las relaciones con el público. Partiendo de este contexto, la siguiente investigación analiza las estrategias de interacción desarrolladas por la corporación de Radio Televisión Pública en España (RTVE) a través de sus perfiles en las redes sociales. Para ello, se ha contabilizado, en primer lugar, el número de cuentas activas en distintas plataformas y dividido en subcategorías segundo su asociación a una serie de ficción, un programa, una de las cadenas o el grupo corporativo. Se ha restringido el recuento a los perfiles sociales relacionados con el medio televisivo, excluyendo así los radiofónicos. A partir de una metodología cuantitativa se han estudiado las estrategias de 3 de sus cuentas: RTVE, TVE y RTVE.es. El objetivo principal es examinar si su nivel de interacción se corresponde con las posibilidades que ofrece el espacio online.

En 2014 la Unión Europea de Radiodifusión (UER) presentaba un informe de valores con el fin de establecer un marco de indicadores intangibles de autoevaluación para los medios de servicio público. Los indicadores de valor e impacto de los servicios públicos y organizaciones se han convertido en uno de los retos de las actuales agendas de gestión. El presente artículo establece una propuesta que se nutre de la herramienta de la UER, compara y evalúa las estrategias de rendición de cuentas de tres radiotelevisiones autonómicas: EITB, CCMA y CRTVG. Los resultados evidencian que, aunque las tres corporaciones reflejan datos financieros, de gestión y gobernanza en sus páginas corporativas e informes anuales, y aunque incrementan las medidas de transparencia con respecto al ámbito institucional y el mercado de la competencia, resultan aún insuficientes a la hora de rendir cuentas a su principal stakeholder: la ciudadanía.

Actomyosin contractility is regulated by phosphorylation of myosin regulatory light chain; much of the work in this area has focused on the kinase. Here the authors use Drosophilafollicle cells and modelling to show that the phosphatase subunit Flapwing controls the initiation and dynamics of actomyosin oscillations.

El periodismo, sumido en la metamorfosis de la sociedad red, de la conectividad y la movilidad, necesita dotarse de técnicas que le permitan afrontar los nuevos desafíos de las complejas sociedades del tercer milenio. Aunque nunca tanto se ha investigado y teorizado sobre el periodismo, lo cierto es que la aplicación del conocimiento científico resultante llega con lentitud a la práctica profesional. Existe un convencimiento bastante extendido entre los actores del ecosistema comunicativo que otros periodismos son posibles. No sólo es preciso la aplicación de los cinco sentidos al ejercicio profesional, sino también la utilización de aparatos biónicos o no que potencien las capacidades de los profesionales. El periodismo biónico es, de momento, un futurible inmediato que puede ofrecer soluciones y que adelanta amenazas.

The original version of this Article contained an error in ref. 39, which incorrectly cited ‘Fristrom, D. & Fristrom, J. W. in The Development of Drosophila melanogaster (eds. Bate, M. & Martinez-Arias, A.) II, (Cold spring harbor laboratory press, 1993)’. The correct reference is ‘Condic, M.L, Fristrom, D. & Fristrom, J.W. Apical cell shape changes during Drosophila imaginal leg disc elongation: a novel morphogenetic mechanism. Development 111: 23-33 (1991)’. Furthermore, the last sentence of the fourth paragraph of the introduction incorrectly omitted citation of work by Rupprecht et al. The correct citation is given below. These errors have now been corrected in both the PDF and HTML versions of the Article. Rupprecht, J.F., Ong, K.H., Yin, J., Huang, A., Dinh, H.H., Singh, A.P., Zhang, S., Yu, W. & Saunders, T.E. Geometric constraints alter cell arrangements within curved epithelial tissues. Mol. Biol. Cell 28, 3582-3594 (2017).

In many regions of our country, and the world, access to laboratory practice in physics and especially electromagnetics is limited. The lack of access to laboratories has significant consequences for students, including the loss of practical experience, limited learning opportunities and less development of technical skills. For this reason, a prototype is presented in this work that allows, remotely, to recognize the capacitor as an energy storage device. For this purpose, a three-phase methodology was followed: i) first, requirements gathering; ii) then, a use case diagram was elaborated to provide a vision of how users interact with the hardware; iii) finally, the services and functions that the program offers to the user were implemented. This facilitates the student the remote execution of the laboratory test, the data collection, its visualization, the downloading of the required graphs and the calculation of the experimental error. Thus, with the data obtained it was possible to determine the time Tau constant of charge and discharge of the capacitor and to study the behavior of its curves. This ratifies the capacitor as an efficient charge storage device and this conclusion can be reached remotely, this type of laboratory tests also promotes a more accessible and inclusive education. [ABSTRACT FROM AUTHOR]