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We define an E∞-coalgebra structure on the chains of multisimplicial sets. Our primary focus is on the surjection chain complexes of McClure-Smith, for which we construct a zig-zag of complexity preserving quasi-isomorphisms of E∞-coalgebras relating them to both the singular chains on configuration spaces and the Barratt–Eccles chain complexes.

En este artículo, realizamos un estudio de la literatura y de la historia de Valparaíso desde fines del período colonial hasta el terremoto de 1906. Proponemos que la ciudad tiene una trayectoria similar a la bíblica Babel, esto es, que pasa desde un territorio agreste a una de las ciudades latinoamericanas más poderosas del siglo XIX. Empleando una serie de recursos teóricos propios de la teoría y la crítica literaria, la filosofía, la historiografía y la geografía, se analiza la progresiva construcción de una “ciudad liberal” que está marcada por el desarrollo económico, demográfico, arquitectónico y, a su vez, por graves diferencias sociales, que generan, en definitiva, un complejo entramado urbano.

AbstractOver recent decades, numerous financial crises have affected the global economy, which were caused by the lack of ethical values and conflicts of interest amongst the leaders of organisations. To protect organisations and their interest groups, regulators have developed norms to discourage and prohibit unethical practices through promotion of good practices of corporate governance. However, the literature on good corporate governance practices focuses mainly on developed economies without considering the challenges of developing countries. Therefore, this research proposes an index to measure the degree of adherence to good corporate governance practices in an emerging economy, like Chile, and estimate its effect on the financial performance of companies. Through a panel analysis, this research provides evidence that shows the existence of a positive and significant relationship between this index and financial performance of organisations, as well as a persistence of its benefits over time when companies adopt good practices.

This article reports on the use of a digital application (EVALOE-SSD) for the professional development of teachers to improve the linguistic competence of their students. We conducted a multiple case study that involved five teachers and their students from different schools. Over a period of three months, the teachers used the digital application to assess their classes, make decisions and introduce changes in their teaching practices. The results show that the change process includes stages of progress and stages of regression, but in general the trend was to a progressive increase in scores. Therefore, the use of the digital application improved the competences of teachers and students, regardless of the type of school or students’ age. This is shown in the cases of two teachers, which are analysed in greater depth. We believe that our findings are important as they document how self-reflection, stimulated by aids such as video recordings, reflective questions and pictures, facilitates a change in teaching practices. At the end of the programme, all the teachers stated that the experience of using the digital tool had clearly been enriching, and they had learnt and improved teaching practice linked to communicative competence.

Coral reefs are highly diverse ecosystems that thrive in nutrient-poor waters, a phenomenon frequently referred to as the Darwin paradox1. The energy demand of coral animal hosts can often be fully met by the excess production of carbon-rich photosynthates by their algal symbionts2,3. However, the understanding of mechanisms that enable corals to acquire the vital nutrients nitrogen and phosphorus from their symbionts is incomplete4–9. Here we show, through a series of long-term experiments, that the uptake of dissolved inorganic nitrogen and phosphorus by the symbionts alone is sufficient to sustain rapid coral growth. Next, considering the nitrogen and phosphorus budgets of host and symbionts, we identify that these nutrients are gathered through symbiont ‘farming’ and are translocated to the host by digestion of excess symbiont cells. Finally, we use a large-scale natural experiment in which seabirds fertilize some reefs but not others, to show that the efficient utilization of dissolved inorganic nutrients by symbiotic corals established in our laboratory experiments has the potential to enhance coral growth in the wild at the ecosystem level. Feeding on symbionts enables coral animals to tap into an important nutrient pool and helps to explain the evolutionary and ecological success of symbiotic corals in nutrient-limited waters.

AbstractObjectiveThe aim of the present study was to compare the frequency of consumption, access to purchase, and type of preparations with pulses among people who eat a vegetarian/vegan or non-vegetarian diet during the COVID-19 pandemic.MethodsCross-sectional surveys were distributed using different digital platforms and social networks. We investigated the frequency of consumption, access to purchase any type of preparations. Descriptive analyses were performed. Differences between the types of diet were tested by Chi-squared statistics.ResultsA total of 3339 adults participated in the survey in March 2021, 80% of the total participants were females; 13.6% were vegetarian or vegan (VV). The consumption of pulses increased by 25% among non-vegetarians and 54.5% in VV (p by 25% among non-vegetarians and 54.5% in VV (vey in March 2021, 80% of the total participants were females; 13.6% were vegetarian or vegan (VV). The consumption of pulses preparations. Descriptive analyses were performfood with high satiating power, when compared with the opinions of non-vegetarians (p ood with high satiating power, when cconsumption of pulses were observed in less than 30% of the respondents, but the percentage was lower among VV, the most common negative beliefs are “They are difficult to prepare” and “My family does not like them.” Food preparations including pulses are more diverse among VV, and consumption being significantly higher in the 10 alternatives of preparations included in the study.ConclusionThese results highlight the importance of identifying the knowledge, practices, frequency, and preferences of consumption of legumes in the population to stimulate their consumption. Although we observed an increase in the consumption of legumes among those in the sample, the VV group showed a higher frequency of consumption, consumption of different types of legumes and varied preparation, and greater knowledge about the beneficial properties of legumes.

Small newborns are vulnerable to mortality and lifelong loss of human capital. Measures of vulnerability previously focused on liveborn low-birthweight (LBW) babies, yet LBW reduction targets are off-track. There are two pathways to LBW, preterm birth and fetal growth restriction (FGR), with the FGR pathway resulting in the baby being small for gestational age (SGA). Data on LBW babies are available from 158 (81%) of 194 WHO member states and the occupied Palestinian territory, including east Jerusalem, with 113 (58%) having national administrative data, whereas data on preterm births are available from 103 (53%) of 195 countries and areas, with only 64 (33%) providing national administrative data. National administrative data on SGA are available for only eight countries. Global estimates for 2020 suggest 13·4 million livebirths were preterm, with rates over the past decade remaining static, and 23·4 million were SGA. In this Series paper, we estimated prevalence in 2020 for three mutually exclusive types of small vulnerable newborns (SVNs; preterm non-SGA, term SGA, and preterm SGA) using individual-level data (2010–20) from 23 national datasets (∼110 million livebirths) and 31 studies in 18 countries (∼0·4 million livebirths). We found 11·9 million (50% credible interval [Crl] 9·1–12·2 million; 8·8%, 50% Crl 6·8–9·0%) of global livebirths were preterm non-SGA, 21·9 million (50% Crl 20·1–25·5 million; 16·3%, 14·9–18·9%) were term SGA, and 1·5 million (50% Crl 1·2–4·2 million; 1·1%, 50% Crl 0·9–3·1%) were preterm SGA. Over half (55·3%) of the 2·4 million neonatal deaths worldwide in 2020 were attributed to one of the SVN types, of which 73·4% were preterm and the remainder were term SGA. Analyses from 12 of the 23 countries with national data (0·6 million stillbirths at ≥22 weeks gestation) showed around 74% of stillbirths were preterm, including 16·0% preterm SGA and approximately one-fifth of term stillbirths were SGA. There are an estimated 1·9 million stillbirths per year associated with similar vulnerability pathways; hence integrating stillbirths to burden assessments and relevant indicators is crucial. Data can be improved by counting, weighing, and assessing the gestational age of every newborn, whether liveborn or stillborn, and classifying small newborns by the three vulnerability types. The use of these more specific types could accelerate prevention and help target care for the most vulnerable babies.

La alimentación complementaria (AC) se define como la alimentación de los lactantes que complementa a la lactancia materna o en su defecto, a la lactancia con un sucedáneo de la leche materna, y es un proceso que va más allá de simplemente una guía sobre qué y cómo introducir los alimentos. La información brindada por parte de los profesionales de la salud debe ser actualizada y basada en evidencia. Existen diferentes guías o documentos de posición a nivel internacional, que, aunque la mayoría de las recomendaciones pueden ser aplicables, hay algunas otras que requieren una regionalización o adecuación a las condiciones y realidad de cada zona. El grupo de trabajo de Nutrición de la Sociedad Latinoamericana de Gastroenterología, Hepatología y Nutrición Pediátrica convocó a un grupo de expertos, representantes de cada uno de los países que conforman la sociedad, con el objetivo de desarrollar un consenso sobre la AC, que incorporó cuando así fue posible, información local que se adapte a la realidad de la región. El objetivo de este documento es mostrar los resultados de dicho trabajo. A través de metodología Delphi, se evaluaron, discutieron y votaron un total de 34 declaraciones o enunciados con respecto a aspectos relevantes de la AC.

Complementary feeding (CF) is defined as the feeding of infants that complements breastfeeding, or alternatively, feeding with a breast milk substitute, and is a process that is more than simply a guide as to what and how to introduce foods. The information provided by healthcare professionals must be up-to-date and evidence-based. Most of the recommendations that appear in the different international guidelines and position papers are widely applicable, but some must be regionalized or adapted to fit the conditions and reality of each geographic zone. The Nutrition Working Group of the Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) summoned a group of experts from each of the society’s member countries, to develop a consensus on CF, incorporating, whenever possible, local information adapted to the reality of the region. The aim of the present document is to show the results of that endeavor. Utilizing the Delphi method, a total of 34 statements on relevant aspects of CF were evaluated, discussed, and voted upon.

AbstractWorking capital management is one of the most important decisions that affect an organisation’s financial performance. Despite the importance of this topic, the empirical evidence for emerging economies is scarce; therefore, this research attempts to estimate and compare how investment in working capital impacts the financial performance of companies listed on the stock exchanges in Chile, Mexico, Peru, and Brazil for the years 2000 to 2018. This study uses panel data methodology, and the results show the existence of a positive and significant but non-linear relationship between investments in working capital and firm performance. However, there are mixed results for different countries and industries that could be explained by macroeconomic variables that favour access to financing for such investments. Furthermore, the results show that investments in working capital perform better for larger companies than smaller companies.

It has long been envisioned that the strength of the barcode invariant of filtered cellular complexes could be increased using cohomology operations. Leveraging recent advances in the computation of Steenrod squares, we introduce a new family of computable invariants on mod 2 persistent cohomology termed Sqk-barcodes. We present a complete algorithmic pipeline for their computation and illustrate their real-world applicability using the space of conformations of the cyclo-octane molecule.

The internalization of the social cost of carbon (SCC) is the most efficient alternative to reduce the emissions that cause global warming. However, the carbon pricing initiatives implemented in many countries differ significantly from the empirical estimates of the SCC. Therefore, this study simulates the economic and environmental effects of internalizing the SCC in all the world’s nations through the environmental extension of a multi-regional input–output (MRIO) price model. The results show that the most affected countries economically are characterized by having an energy matrix with high participation of fossil fuels. In addition, there are relevant increases in the prices of energy and food, which are likely to raise poverty rates in low- and middle-income countries. It is concluded that the global emission reduction can vary between 5.1% and 50.3% depending on the SCC used, and only ten countries explain 77% of this reduction. In addition, global emissions reduction falls if data from a more recent base year is used, demonstrating that the structural transformations of the economy also strongly affect the impacts of carbon pricing. Finally, it is recommended that energy efficiency measures be incentivized to address partially this cost shock.

In this investigation, we propose a new species in Telimena, T. bromeliae sp. nov. growing on bromeliads with a detailed description, illustrations, and molecular characterisation based on material collected in Costa Rica and Panama. Additionally, four species of Phyllachora occurring on non-graminicolous hosts are transferred into Telimena based on morphological and molecular data: T. amphibola comb. nov. on Inga spp. and T. tenuis comb. nov. on Bauhinia spp. (Fabaceae, Cercidiodeae); T. dominicana comb. nov. on Coccoloba spp.; and T. rubefaciens comb. nov. on Clethra spp. (Clethraceae). The species with newly combined names are redescribed and fully illustrated from type specimens and material recently collected in Costa Rica, Florida (USA) and Panama. Additionally, a revision of tropical tar spot fungi on host species belonging to the family Polygonaceae is provided, including a dichotomous key of known species and geographical distribution data.

Eucryphia cordifoliaCav. native to the forests of southern Chile, was used for medicinal purposes by the Mapuche people in ancient times. However, there are no recent studies on the biological properties of its leaves in their natural habitat. This study assessed how the location of E. cordifoliapopulations in their ecological niche (center or periphery) impacts the chemical composition, antioxidant activity, and antimicrobial properties of leaf extracts.

The use of regional kinematic reference frames (mRFs) in seismic zones is uncommon worldwide. This article proposes a solution implemented for Chilean mining, whose current projects are based on the classic reference frames (PSAD56 and SAD69). The approach is to move from a classic reference frame to an mRF in seismic countries where earthquakes constantly alter the frame. Our research group calculated an mRF (REDGEOMIN) that includes interseismic, coseismic, and postseismic deformation using CORS with open data from 2009 to 2022 and processed with scientific standards global navigation satellite system. REDGEOMIN consists of a deformation model (ADELA) with an interpolation approach through thin plate spline, allowing the greatest deformation to be modelled at campaign points. The relationship between classical and modern systems was explored with conformal transformations and NTv2 grids to include deformations, especially coming from PSAD56 and SAD69. The results demonstrate that REDGEOMIN aligns with the IGb14 reference frame (<1.0 mm), SIRGAS (ENU = 1.0, 1, 0, 2.0 mm), and the Chilean national reference frame SIRGASChile@2021.00 (ENU = 1, 2, 1, 6, 4.3 mm) aligns with millimetric precision. ADELA deformation model accurately models period locations to within 5 mm. Densification of REDGEOMIN@2022.00 at passive points PSAD56/SAD69 shows centimetric precision. PSAD56/SAD69, adjusted in the 1970s, are outdated due to crustal movement and seismic events and have metric errors. Therefore, different types of transformations were evaluated between PSAD56/SAD69 and REDGEOMIN@2022, whose RMS is between 1.57 and 1.69 m, and national grid transformations (NTv2) with an RMS of 0.23 and 0.16 m for PSAD56 and SAD69, respectively. The relationship between the classic systems and REDGEOMIN allows the transformation of the entire Chilean mining cadastre to epoch 2022.00. Starting in 2022.00, REDGEOMIN/ADELA offers millimetre precision, which is crucial in seismic zones. Furthermore, it paves the way to implement an updated national-level mRF in case of seismic events. Currently, Chilean mining laws are rigid, geodesically speaking. Therefore, legal-technical suggestions for implementing REDGEOMIN are also included in this article.

El receptor de melanocortina 4 (MC4R)participa en el control del apetito a nivel del sistema nervioso central, a través de la vía de la leptina-melanocortina. Se ha reportado asociación entre diferentes polimorfismos del gen MC4Ry la obesidad; sin embargo, existen escasos estudios del polimorfismo de nucleótido simple (SNP) rs483145 de este gen.

In 1947, N.E. Steenrod defined the Steenrod Squares, which are mod 2 cohomology operations, using explicit cochain formulae for cup-iproducts of cocycles. He later recast the construction in more general homological terms, using group homology and acyclic model methods, rather than explicit cochain formulae, to define mod poperations for all primes p. Steenrod’s student J. Adem applied the homological point of view to prove fundamental relations, known as the Adem relations, in the algebra of cohomology operations generated by the Steenrod operations. In this paper we give a proof of the mod 2 Adem relations at the cochain level. Specifically, given a mod 2 cocycle, we produce explicit cochain formulae whose coboundaries are the Adem relations among compositions of Steenrod Squares applied to the cocycle, using Steenrod’s original cochain definition of the Square operations.

Background and objective: Lupus nephritis (LN) is a major complication in patients with systemic lupus erythematosus (SLE). Tubulointerstitial injury is an inflammatory process that, if not attenuated, can promote renal damage. Despite this, the current 2003 ISN/RPS “glomerulocentric” classification does not include a score for tubulointerstitial injury. We sought to establish predictors for tubulointerstitial injury and to determine their influence on renal outcomes. Methods: This is a retrospective study of a cohort of 166 patients with biopsy-proven LN diagnosed in a Spanish referral center, with a median follow-up of 86 months. Chronic tubulointerstitial lesions were defined as interstitial fibrosis and tubular atrophy (IF/TA), whereas tubulointerstitial inflammation (TII) was defined as an acute interstitial lesion. Activity (0–24) and chronicity (0–12) indices were assigned. Outcome: Composite outcome, defined as advanced CKD or development of kidney failure. Results: The prevalence of tubulointerstitial lesions was 69.3%. Eighty-one of the biopsies had features of tubulointerstitial inflammation and only 6 of these 81 (7%) patients had moderate/severe tubulointerstitial inflammation. The incidence of interstitial fibrosis and tubular atrophy was 56.6%. Renal survival was shorter in patients with moderate/severe as compared with absent/mild interstitial fibrosis and tubular atrophy (median: 15–19 years, p = 0.009). In the Cox regression model, the grade of interstitial fibrosis and tubular atrophy was independently associated with shorter renal survival (hazard ratio: 3.9, 95% CI 1.4–10.5; p = 0.008) after adjusting for degree of IF/TA and hypertension or diabetes. Conclusions: The extent of tubulointerstitial inflammation emerged as an independent predictor of renal survival after adjusting for the grade of interstitial fibrosis and tubular atrophy and co-morbid conditions including hypertension or diabetes. Regarding disease duration at the time of renal biopsy, no significant association was found between the interstitial fibrosis and tubular atrophy groups. The results reported herein need to be validated in future studies to include also groups of patients who usually have a worse prognosis. Consensus on histological classification is needed to aid in defining prognosis. Graphical abstract:

AbstractThe evolution of birth weight (BW), birth length (BL), and gestational age at delivery (GAD) and their correlation with various maternal sociodemographic variables were studied in Chilean newborns from years 1996 to 2017. A slight decrease in the mean values of these perinatal outcomes was observed; however, their risk sub-categories increased significantly, especially for GAD, indicating an important deterioration. GAD was strongly correlated with BW and BL. In the contingency tables, all sociodemographic variables, with the exemption of sex, had a higher proportion of early term 37–38-week and late pre-term 34–36-week newborns in women with a higher socioeconomic level; the strongest positive association was observed between mother’s years of education and the GAD risk category 37–38 weeks. Different maternal factors, such as a higher frequency of cesarean sections, including either obesity presence or smoking habit, could be influencing presented results.