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The 16MnCr5 alloy steel samples are evaluated in a normalized condition and put through low cycle fatigue (LCF) under constant amplitude strains of εa = 0.2%, 0.25%, 0.4%, and 0.6%. Mechanical properties are reported based on the LCF results. Fatigue damage is checked in specimens that have reached 80% of their nominal fatigue life by two methods that are different from traditional electronic microscopy: measuring the roughness of the surface and looking at it through full‐field optical microscopy. In addition, the electric resistivity is determined for the test specimens. It presents an increment from the blank value of 6.5 × 10−8 Ωm (free of fatigue damage) to 1.25 × 10−7 Ωm for the fatigue test specimen (εa = 0.6%). Finally, X‐ray diffraction patterns are determined for analyzing the residual equivalent strain at the microscale for the fatigued samples. The residual equivalent strain exhibits a trend toward increasing. For instance, it increases from 18.5 (blank value) to 34.0 με for the fatigue test specimen with εa = 0.6%. [ABSTRACT FROM AUTHOR]

In this work, functional scaffolds based on electrospun chitosan nanofibers are unprecedentedly studied in terms of their force cell adhesion response. To prove cell compatibility of this biomaterial, chondrocyte interactions are investigated using atomic force microscopy in which a single cell is fixed to the cantilever and approached to the chitosan mat for a given contact time. Then, the cantilever is retracted and cell interactions are studied. Force jumps distribution for cell detachment is described and the adhesion energy is determined comparing nanofiber mats with homogeneous films and a BSA coated surface as control. Force adhesion on chitosan films, equals 460 ± 150 pN, is found slightly higher than on porous fiber mats (410 ± 135 pN) indicating that more cell-substrate bonds could be formed on a flat contact surface for a contact time of 60 s. The same trend was observed for a contact of 120 s between the cell and the substrate. The adhesion on hydrophilic chitosan surface at t = 60 s, is much larger than on the control surface (210 ± 90 pN) due to its positive character and ability for H-bond stabilization. [ABSTRACT FROM AUTHOR]

Assuming that the prey refuge is proportional to the prey density if its population size is below a critical threshold, or constant if its size is above the threshold, this paper proposes, and qualitatively analyzes, a Leslie–Gower predator–prey model assuming alternative feeding and harvesting in predators, and a Holling II function as the predator functional response. From the results of the mathematical analysis to the predator–prey models with proportional or constant prey refuge, the proposed model retains the same bifurcation cases obtained for each model analyzed. However, appropriate alterations of the parameters representing the critical threshold of prey population size and harvest in predators allows the formation of at least one limit cycle, stable or unstable, that lives in both vector fields of the proposed model. [ABSTRACT FROM AUTHOR]

Objective. To analyze the association of total globalization and its different dimensions with overweight and obesity in 10 Latin American and Caribbean (LAC) countries between 1995 and 2013. Materials and methods. A sample of 848 405 women aged 20-49 was analyzed. Multiple logistic regression models were used, adjusting for individual- and country-level confounding factors. To evaluate nonlinearities, four levels were defined through quartiles and divided into four dummy variables. Results. Total globalization had a positive association with overweight and obesity. Three dimensions of globalization (economic, political and social) indicated an increase in overweight and obesity. Social globalization presented polynomial behaviour, whereas, in political and economic globalization, a concave relation was observed. Conclusion. The economic, political and social dimensions had a positive association with overweight and obesity. [ABSTRACT FROM AUTHOR]

Nucleic acids are central to information transfer and replication in living systems, providing the molecular foundations of Darwinian evolution. Here we report that prebiotic acetylation of the non-natural, but prebiotically plausible, ribonucleotide α-cytidine-5′-phosphate, selectively protects the vicinal diol moiety. Vicinal diol acetylation blocks oxazolidinone formation and prevents C2′-epimerization upon irradiation with UV-light. Consequently, acetylation enhances (4-fold) the photoanomerization of α-cytidine-5′-phosphate to produce the natural β-pyrimidine ribonucleotide-5′-phosphates required for RNA synthesis. [ABSTRACT FROM AUTHOR]

Objective. Estimate mortality and economic costs from cardiovascular diseases attributable to physical inactivity in Argentina. Methods. Attributable mortality (AM) from physical inactivity was estimated as the product of the population attributable fraction and the number of deaths caused by associated cardiovascular diseases. Value of statistical life (VSL) was calculated using the human capital approach, in which VSL was estimated through lost productivity from premature death. Economic costs were calculated using AM and VSL, stratifying by sex, age group, and physical activity level. A sensitivity analysis was used to evaluate how costs vary in three possible scenarios. Results. AM from low and moderate physical activity ranged from 33 (18 to 24 years) to 7 857 (>84 years) deaths annually in both sexes. VSL ranged from I$441 005 (international dollars) (18 to 24 years) to I$4,121 (>84 years). Assessment of total costs by sex indicates that economic losses amounted to I$752.5 million for men and I$444.5 million for women. Conclusion. Economic losses ranged from 0.61% of GDP for the minimum scenario, 0.85% for the average scenario, and 1.48% for the maximum scenario. Stronger public policy-making aimed at reduction of sedentary lifestyles in Argentina is recommended. [ABSTRACT FROM AUTHOR]

The central role that phosphates play in biological systems, suggests they also played an important role in the emergence of life on Earth. In recent years, numerous important advances have been made towards understanding the influence that phosphates may have had on prebiotic chemistry, and here, we highlight two important aspects of prebiotic phosphate chemistry. Firstly, we discuss prebiotic phosphorylation reactions; we specifically contrast aqueous electrophilic phosphorylation, and aqueous nucleophilic phosphorylation strategies, with dry-state phosphorylations that are mediated by dissociative phosphoryl-transfer. Secondly, we discuss the non-structural roles that phosphates can play in prebiotic chemistry. Here, we focus on the mechanisms by which phosphate has guided prebiotic reactivity through catalysis or buffering effects, to facilitating selective transformations in neutral water. Several prebiotic routes towards the synthesis of nucleotides, amino acids, and core metabolites, that have been facilitated or controlled by phosphate acting as a general acid-base catalyst, pH buffer, or a chemical buffer, are outlined. These facile and subtle mechanisms for incorporation and exploitation of phosphates to orchestrate selective, robust prebiotic chemistry, coupled with the central and universally conserved roles of phosphates in biochemistry, provide an increasingly clear message that understanding phosphate chemistry will be a key element in elucidating the origins of life on Earth. [ABSTRACT FROM AUTHOR]

The role of Higher Education in developing scientific research at Ecuadorean Universities is presented in this paper, before and after the implementation of the education model established since 2008, which perceives these institutions as agents that generate social, cultural and environmental change with a vision of complex and integrating thought. It was found, through an exploratory and descriptive investigation, that the academic system in Ecuador over years had a teaching approach, different to the one used today. The successes achieved are presented mainly in scientific production at universities and in their staff's academic level. The need to implement strategies for eliminating the existing weaknesses in order to achieve international recognition is also stressed. [ABSTRACT FROM AUTHOR]

A convenient selective synthesis of 2′,3′-di-O-acetyl-nucleotide-5′-phosphates, 2′,3′-di-O-acetyl-nucleotide-5′-triphosphates and 2′,3′,5′-tri-O-acetyl-nucleosides in water has been developed. Furthermore, a long-chain selective glycerol-3-phosphocholine diacylation is elucidated. These reactions are environmentally benign, rapid, high yielding, and the products are readily purified. Importantly, this reaction may indicate a prebiotically plausible reaction pathway for the selective acylation of key metabolites to facilitate their incorporation into protometabolism. [ABSTRACT FROM AUTHOR]

A oxigenação por membrana extracorpórea é utilizada em casos de hipoxemia refratária em diversas condições clínicas. Pacientes vítimas de traumatismo torácico geralmente desenvolvem síndrome da angústia respiratória aguda. Em razão do elevado risco de sangramentos, as complicações trombóticas que se apresentam neste contexto são particularmente difíceis de tratar e, geralmente, demandam a inserção de um filtro na veia cava inferior, com a finalidade de prevenir a migração de êmbolos oriundos das veias distais para a circulação pulmonar. Neste artigo, apresentamos o caso de um paciente com traumatismo torácico, que apresentou grave síndrome de angústia respiratória aguda, com necessidade de utilizar oxigenação por membrana extracorpórea aplicada por meio da introdução de uma cânula com duplo-lúmen na veia jugular interna direita. Este procedimento foi realizado tendo em vista a prévia inserção de um filtro na veia cava inferior, por conta da ocorrência de trombose venosa profunda em ambas as panturrilhas. Extracorporeal membrane oxygenation is used in refractory hypoxemia in many clinical settings. Thoracic trauma patients usually develop acute respiratory distress syndrome. Due to high risk of bleeding, thrombotic complications present in this context are particularly difficult to manage and usually require insertion of an inferior vena cava filter to prevent embolism from the distal veins to the pulmonary circulation. Here, we present a case of a thoracic trauma patient with severe acute respiratory distress syndrome requiring venovenous extracorporeal membrane oxygenation via a right internal jugular double lumen cannula due to a previously inserted inferior vena cava filter caused by distal bilateral calf muscle vein deep vein thrombosis. [ABSTRACT FROM AUTHOR]

Abstract The biodiversity of animal species in the Última Esperanza inland sea (Magallanes region, Chile) provides an exceptional opportunity to study the economic and organizational strategies of maritime hunter-gatherer groups in the Fuego-Patagonian archipelago. The consumption of huemul (Hippocamelus bisulcus) in Southern South America is well documented since the Middle Holocene, although its role in the subsistence strategies of maritime hunter-gatherers varies depending on the geographical and environmental area. The aim of this paper is to assess the implications of huemul exploitation on organizational strategies by Late Holocene maritime hunter-gatherer groups from the Última Esperanza inland sea (Magallanes region, Chile). In this work we present the results of a zooarchaeological analysis of the huemul assemblage from the sites of Bahía Easter 1 and Bahía Easter 2 (Diego Portales Island, Última Esperanza, Chile). The results show the high importance of huemul in the maritime hunter-gatherer diet, and provide new insights into the hunting and transport strategies of this prey. Furthermore, the integration of the data within the local and regional archaeological record allowed us to identify similarities at the scale of the inland sea, where huemul was frequently exploited both in island and coastal environments in contrast to what is documented in the neighboring Skyring Sea and Otway Sea. [ABSTRACT FROM AUTHOR]

Respiratory diseases, including influenza and coronaviruses, pose recurrent global threats. This study delves into the respiratory surveillance systems, focusing on the effectiveness of SARI sentinel surveillance for total and severe cases incidence estimation. Leveraging data from the COVID-19 pandemic in Chile, we examined 2020–2023 data (a 159-week period) comparing census surveillance results of confirmed cases and hospitalizations, with sentinel surveillance. Our analyses revealed a consistent underestimation of total cases and an overestimation of severe cases of sentinel surveillance. To address these limitations, we introduce a nowcasting model, improving the precision and accuracy of incidence estimates. Furthermore, the integration of genomic surveillance data significantly enhances model predictions. While our findings are primarily focused on COVID-19, they have implications for respiratory virus surveillance and early detection of respiratory epidemics. The nowcasting model offers real-time insights into an outbreak for public health decision-making, using the same surveillance data that is routinely collected. This approach enhances preparedness for emerging respiratory diseases by the development of practical solutions with applications in public health. [ABSTRACT FROM AUTHOR]

Background: Minimally invasive surgery has a different visual and tactile perception compared with conventional surgery, which could lead to complications, especially in complex procedures. In these cases, flexible endoscopy can facilitate and prevent complications in minimally invasive procedures in children. The study aimed to clarify the utility of intraoperative endoscopy as an adjuvant to minimally invasive surgery in children. Materials and Methods: This retrospective study reviewed the medical records of pediatric patients who had undergone endoscopy during a minimally invasive surgery to treat an upper digestive pathology between January 2000 and December 2020. Results: The study included 83 patients who underwent a laparoscopic procedure with simultaneous endoscopy. The diagnosis was peptic stenosis in 9 patients, achalasia in 23, congenital embryonic tracheobronchial remnants in 4, re-fundoplication in 42, esophageal duplication in 2, superior mesenteric artery syndrome in 2, and giant gastric hemangioma in 1 patient. With adjuvant endoscopy, 7 digestive perforations were noted, 11 cases of short esophagus were diagnosed, and the permeability of the anastomosis was confirmed in 6 cases. No complications were related with the endoscopy procedures. Discussion: Minimally invasive surgery has a few special and tactile limitations that can lead to complications in certain procedures. Simultaneous digestive endoscopy in the upper gastrointestinal tract facilitates organ identification and dissection. Conclusion: Digestive endoscopy is an excellent adjunct to minimally invasive surgery in children because it facilitates and identifies complications and ensures safer minimally invasive surgeries. Future prospective studies are required to assess this conclusion. [ABSTRACT FROM AUTHOR]

as zonas verdes de áreas universitarias representan un valor más allá de un espacio de recreación y esparcimiento estudiantil, tienen un importante rol ecológico, pues son espacios de producción de oxígeno, retención de humedad, albergan fauna nativa de gran importancia, como polinizadores y dispersores de semillas, controlan la polución, actúan como amortiguadores de temperatura y permiten el establecimiento de especies silvestres de briófitos y hongos. La sede principal de la Universidad El Bosque se encuentra en la localidad de Usaquén, de la ciudad de Bogotá, en una altitud de 2553 m; por la ubicación del campus, sus zonas verdes pueden representar un área de comunicación de la biota, entre los cerros orientales y la urbe. Por estas razones es importante promover la conservación de las mismas, generando en primera medida el interés por el conocimiento de la riqueza vegetal que se tiene en la ciudad. Este trabajo fue desarrollado por los estudiantes del Semillero de Biología vegetal de la Universidad, se hizo un inventario de las plantas vasculares (angiospermas, gimnospermas y monilófitos) que se encontraban en las jardineras y otras áreas verdes del campus, de cada especie se tomó un registro fotográfico y se recolectó una muestra para la preparación de un un ejemplar botánico, el cual se depositó en el Herbario de la Universidad El Bosque HUEB. Como resultado se encontraron 137 especies de plantas vasculares, 88 dicotiledóneas, 35 monodicotiledóneas, 7 monilófitos y 6 gimnospermas. Las familias más abundantes fueron Fabaceae (8 especies), Orchidaceae (7 especies), Bromeliaceae (6 especies), Crassulaceae (6 especies), Poaceae, Verbenaceae y Lamiaceae, estas últimas con 4 especies cada una. De las plantas identificadas, 96 son plantas exóticas y 41 son nativas. Dentro de las especies nativas se destacan Retrophyllum rospigliosii, Quercus humboldtii, Lafoensia acuminata, Myrcianthes leucoxyla y Tibouchina lepidota, las cuales son unas de las especies arbóreas más importantes en el bosque andino, además hay que destacar que la universidad puede ser foco de dispersión de éstas, lo cual cobra importancia, teniendo en cuenta que las dos primeras se encuentran en las categoría de Casi Amenazada y Vulnerable, respectivamente [1]. Finalmente, en cuanto a hábitos de crecimiento, la flora de la Universidad está compuesta por un 74% de hierbas de bajo porte, 36% de árboles, 16% de arbustos, 6% de trepadoras y 5% de hierbas de gran porte. [ABSTRACT FROM AUTHOR]

Las zonas verdes de áreas universitarias representan un valor más allá de un espacio de recreación y esparcimiento estudiantil, tienen un importante rol ecológico, pues son espacios de producción de oxígeno, retención de humedad, albergan fauna nativa de gran importancia, como polinizadores y dispersores de semillas, controlan la polución, actúan como amortiguadores de temperatura y permiten el establecimiento de especies silvestres de briófitos y hongos. La sede principal de la Universidad El Bosque se encuentra en la localidad de Usaquén, de la ciudad de Bogotá, en una altitud de 2553 m; por la ubicación del campus, sus zonas verdes pueden representar un área de comunicación de la biota, entre los cerros orientales y la urbe. Por estas razones es importante promover la conservación de las mismas, generando en primera medida el interés por el conocimiento de la riqueza vegetal que se tiene en la ciudad. Este trabajo fue desarrollado por los estudiantes del Semillero de Biología vegetal de la Universidad, se hizo un inventario de las plantas vasculares (angiospermas, gimnospermas y monilófitos) que se encontraban en las jardineras y otras áreas verdes del campus, de cada especie se tomó un registro fotográfico y se recolectó una muestra para la preparación de un un ejemplar botánico, el cual se depositó en el Herbario de la Universidad El Bosque HUEB. Como resultado se encontraron 137 especies de plantas vasculares, 88 dicotiledóneas, 35 monodicotiledóneas, 7 monilófitos y 6 gimnospermas. Las familias más abundantes fueron Fabaceae (8 especies), Orchidaceae (7 especies), Bromeliaceae (6 especies), Crassulaceae (6 especies), Poaceae, Verbenaceae y Lamiaceae, estas últimas con 4 especies cada una. De las plantas identificadas, 96 son plantas exóticas y 41 son nativas. Dentro de las especies nativas se destacan Retrophyllum rospigliosii, Quercus humboldtii, Lafoensia acuminata, Myrcianthes leucoxyla y Tibouchina lepidota, las cuales son unas de las especies arbóreas más importantes en el bosque andino, además hay que destacar que la universidad puede ser foco de dispersión de éstas, lo cual cobra importancia, teniendo en cuenta que las dos primeras se encuentran en las categoría de Casi Amenazada y Vulnerable, respectivamente [1]. Finalmente, en cuanto a hábitos de crecimiento, la flora de la Universidad está compuesta por un 74% de hierbas de bajo porte, 36% de árboles, 16% de arbustos, 6% de trepadoras y 5% de hierbas de gran porte. [ABSTRACT FROM AUTHOR]

The central and conserved role of peptides in extant biology suggests that they played an important role during the origins of life. Strecker amino acid synthesis appears to be prebiotic, but the high pKaH of ammonia (pKaH = 9.2) necessitates high pH reaction conditions to realise efficient synthesis, which places difficult environmental constraints on prebiotic amino acid synthesis. Here we demonstrate that diamidophosphate reacts efficiently with simple aldehydes and hydrogen cyanide in water at neutral pH to afford N-phosphoro-aminonitriles. N-Phosphoro-aminonitrile synthesis is highly selective for aldehydes; ketones give poor conversion. N-Phosphoro-aminonitriles react with hydrogen sulfide at neutral pH to furnish aminothioamides. The high yield (73%–Quant.) of N-phosphoro-aminonitriles at neutral pH, and their selective transformations, may provide new insights into prebiotic amino acid synthesis and activation. The Strecker reaction is thought to offer a prebiotically plausible synthesis of amino acids, but is reversible at the high or low pH ranges needed to promote reactivity. Here the reaction of hydrogen cyanide and diamidophosphate is shown to provide stable phosphorylated amino acid precursors at neutral pH, which can be hydrolysed to amino acids or thiolysed to thioamides. [ABSTRACT FROM AUTHOR]

Peptide biosynthesis is performed by ribosomes and several other classes of enzymes, but a simple chemical synthesis may have created the first peptides at the origins of life. a-Aminonitriles—prebiotic a–amino acid precursors—are generally produced by Strecker reactions. However, cysteine’s aminothiol is incompatible with nitriles. Consequently, cysteine nitrile is not stable, and cysteine has been proposed to be a product of evolution, not prebiotic chemistry. We now report a high-yielding, prebiotic synthesis of cysteine peptides. Our biomimetic pathway converts serine to cysteine by nitrile-activated dehydroalanine synthesis. We also demonstrate that N-acylcysteines catalyze peptide ligation, directly coupling kinetically stable—but energy-rich—a-amidonitriles to proteinogenic amines. This rare example of selective and efficient organocatalysis in water implicates cysteine as both catalyst and precursor in prebiotic peptide synthesis. [ABSTRACT FROM AUTHOR]

Los páramos son ecosistemas estratégicos, debido a su gran poder de captación y regulación de agua. En ellos se generan y nacen gran parte de las fuentes de agua que comprenden una compleja red hidrológica, estas áreas prestan servicios ambientales muy importantes, siendo el más sobresaliente su papel en la producción y regulación hídrica. En estas áreas los hongos liquenizados se pueden utilizar como bioindicadores mediante el registro de todas las especies presentes en un área específica, y a través de la toma de muestras individuales de especies de líquenes y la medición de los contaminantes que se acumulan en el talo [1]; el efecto de la concurrencia entre las especies liquénicas que van a coexistir en la misma comunidad, provoca una competencia por espacio; aquellas poblaciones con adaptaciones morfológicas y fisiológicas más adecuadas para el ambiente, o con mayores rangos de tolerancia para ciertos factores, tendrán una mayor capacidad de colonización. En este estudio se evaluó la abundancia, riqueza y distribución de las especies de hongos liquenizados en relación con el tipo de vegetación y la distancia con el centro de la actividad extractiva de una mina de carbón, propiedad de la empresa "Minas El Santuario", ubicada en el municipio de Tausa - Cundinamarca. Se registraron 122 especies, distribuidas en 24 familias y 35 géneros. Las especies que se encontraron con mayor abundancia fueron Everniastrum catawbiense, Oropogon sp., Usnea fragilescens, Usnea silesiaca. En cuanto a géneros, los más abundantes fueron Everniastrum y Usnea; a su vez, la familia con más riqueza fue Parmeliaceae. Se encontró que en las áreas donde existe mayor grado de intervención se presentan las especies Candelariella sp., Hypocenomyce sp., Parmotrema dilatatum, Parmotrema rampoddense, Rhizocarpon distinctum, Stereocaulon tomentosum y Verrucaria sp., por lo cual se consideraron indicadoras de perturbación; mientras las especies Hypotrachyna meyeri, Parmotrema sp., Peltigera collina, Ramalina dendriscoide, Sticta andensis, Sticta fuliginoides, Sticta humboldtii, Sticta weigelii, Graphis sp., Pannaria sp., Parmotrema dominicanum, Phaeographis sp. y Usnea glabrescens solo se encontraron en las áreas donde aún se mantiene conservado la vegetación paramuna, por lo cual se consideraron indicadoras de zonas conservadas. Se observó que el índice de diversidad de Shannon es un buen indicador de los efectos de la intervención antrópica sobre la diversidad de estos organismos. [ABSTRACT FROM AUTHOR]

Los páramos son ecosistemas estratégicos, debido a su gran poder de captación y regulación de agua. En ellos se generan y nacen gran parte de las fuentes de agua que comprenden una compleja red hidrológica, estas áreas prestan servicios ambientales muy importantes, siendo el más sobresaliente su papel en la producción y regulación hídrica. En estas áreas los hongos liquenizados se pueden utilizar como bioindicadores mediante el registro de todas las especies presentes en un área específica, y a través de la toma de muestras individuales de especies de líquenes y la medición de los contaminantes que se acumulan en el talo [1]; el efecto de la concurrencia entre las especies liquénicas que van a coexistir en la misma comunidad, provoca una competencia por espacio; aquellas poblaciones con adaptaciones morfológicas y fisiológicas más adecuadas para el ambiente, o con mayores rangos de tolerancia para ciertos factores, tendrán una mayor capacidad de colonización. En este estudio se evaluó la abundancia, riqueza y distribución de las especies de hongos liquenizados en relación con el tipo de vegetación y la distancia con el centro de la actividad extractiva de una mina de carbón, propiedad de la empresa "Minas El Santuario", ubicada en el municipio de Tausa - Cundinamarca. Se registraron 122 especies, distribuidas en 24 familias y 35 géneros. Las especies que se encontraron con mayor abundancia fueron Everniastrum catawbiense, Oropogon sp., Usnea fragilescens, Usnea silesiaca. En cuanto a géneros, los más abundantes fueron Everniastrum y Usnea; a su vez, la familia con más riqueza fue Parmeliaceae. Se encontró que en las áreas donde existe mayor grado de intervención se presentan las especies Candelariella sp., Hypocenomyce sp., Parmotrema dilatatum, Parmotrema rampoddense, Rhizocarpon distinctum, Stereocaulon tomentosum y Verrucaria sp., por lo cual se consideraron indicadoras de perturbación; mientras las especies Hypotrachyna meyeri, Parmotrema sp., Peltigera collina, Ramalina dendriscoide, Sticta andensis, Sticta fuliginoides, Sticta humboldtii, Sticta weigelii, Graphis sp., Pannaria sp., Parmotrema dominicanum, Phaeographis sp. y Usnea glabrescens solo se encontraron en las áreas donde aún se mantiene conservado la vegetación paramuna, por lo cual se consideraron indicadoras de zonas conservadas. Se observó que el índice de diversidad de Shannon es un buen indicador de los efectos de la intervención antrópica sobre la diversidad de estos organismos. [ABSTRACT FROM AUTHOR]

Abstract Little is known about the prevalence of Balamuthia mandrillaris within the environment due to its difficult isolation, but once an axenic culture is established, it is relatively easy to maintain. As most of the time researchers are interested mainly in isolating B. mandrillaris from environmental samples, the flora that accompanies it becomes second in importance. Therefore, this study aimed to determine which potentially pathogenic free-living amoebae, in addition to B. mandrillaris , could be found co-inhabiting a source of natural thermal water called "Agua Caliente" (Mexico), where this amoeba has previously been detected twice by molecular methods. A third sampling from this same source was carried out to try to isolate B. mandrillaris and other free-living amoebae using 37 and 45 °C as isolation temperatures. For PCR techniques, specific primers were used for B. mandrillaris , Naegleria fowleri , and Acanthamoeba species, plus a universal primer set for the eukaryotic 18S SSU rRNA gene for other isolated amoebae. PCR products were sequenced for final identification. 42 strains of the primary isolate were obtained, but only 34 could be kept in culture. Of them, 23 strains were identified as Naegleria lovaniensis , eight strains as Acanthamoeba jacobsi , two strains as Stenamoeba sp. and only one was identified as Vermamoeba vermiformis. The isolation of B. mandrillaris was once again not successful, but the presence of potentially pathogenic and nonpathogenic free-living amoebae is reported for the first time in this type of water in Mexico thanks to molecular methodology. Graphical abstract Image Highlights • Pathogenic amoebae isolated from one natural thermal source water. • Balamuthia mandrillaris was identified by PCR in two different years from the same source water. • Acanthamoeba jacobsi and Stenamoeba spp. are reported for first time in Mexico. [ABSTRACT FROM AUTHOR]

Background: The criteria for the selection of COVID‐19 patients that could benefit most from ECMO organ support are yet to be defined. In this study, we evaluated the predictive performance of ECMO mortality predictive models in patients with COVID‐19. We also performed a cost–benefit analysis depending on the mortality predicted probability. We conducted a retrospective cohort study in COVID‐19 patients who received ECMO at two tertiary care hospitals between March 2020 to July 2021. Materials and Methods: We evaluated the discrimination (C‐statistic), calibration (Cox calibration), and accuracy of the prediction of death due to severe ARDS in V‐V ECMO score (PRESERVE), the Respiratory Extracorporeal Membrane Oxygenation Survival Score (RESP) score, and the PREdiction of Survival on ECMO Therapy‐Score (PRESET) score. In addition, we compared the RESP score with Plateau pressure instead of Peak pressure. Results: We included a total of 36 patients, 29 (80%) of them male and with a median (IQR) APACHE of 10 (8–15). The PRESET score had the highest discrimination (AUROCs 0.81 [95%CI 0.67–0.94]) and calibration (calibration‐in‐the‐large 0.5 [95%CI −1.4 to 0.3]; calibration slope 2.2 [95%CI 0.7/3.7]). The RESP score with Plateau pressure had higher discrimination than the conventional RESP score. The cost per QALY in the USA, adjusted to life expectancy, was higher than USD 100 000 in patients older than 45 years with a PRESET > 10. Conclusion: The PRESET score had the highest predictive performance and could help in the selection of patients that benefit most from this resource‐demanding and highly invasive organ support. [ABSTRACT FROM AUTHOR]

Aim: The aim of this case‐control study was to evaluate the association between the TNFSF13B rs9514828 (−871 C > T) polymorphism and soluble BAFF (sBAFF) in apical periodontitis (AP) patients. Methodology: Two hundred and sixty one healthy subjects (HS) and 158 patients with AP classified as: 46 acute apical abscess (AAA), 81 primary AP (pAP) and 31 secondary AP (sAP) patients were included. Genomic DNA (gDNA) was extracted from peripheral blood cells according to the salting out method. The TNFSF13B rs9514828 (NC_000013.11:g.108269025C > T) were identified using polymerase chain reaction (PCR) followed by restriction fragment length polymorphisms (RFLP). Serum sBAFF levels were measured by ELISA test. The chi‐squared or Fisher's exact test was performed. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to evaluate the risk of AP associated with the rs9514828. The Mann–Whitney U test and Kruskal–Wallis analysis were used for non‐normally distributed data. Differences were considered significant with a p‐value <.05. Results: No differences in the genotype/allele frequencies were shown between HS and patients with AAA. However, the TT genotype (OR = 2.68, 95% CI: 1.10–6.53; p =.025) and T allele (OR = 1.46, 95% CI: 1.00–2.12; p =.045) were associated with increased risk of pAP. In contrast, the minor allele T significantly decreased the risk of sAP (OR = 0.49, 95% CI: 0.024–0.99; p =.043). sBAFF serum levels were increased in AAA and pAP compared with HS (p <.01 and p =.021, respectively). The AAA patients had higher sBAFF serum levels than pAP (p =.034) and sAP (p <.01). Conclusions: These results suggest that the TNFSF13B rs9514828 (−871 C > T) polymorphism is associated with pAP susceptibility and that BAFF is a cytokine that might be involved in acute and chronic AP. The future exploration of the rs9514828 polymorphism in other AP cohorts is recommended. [ABSTRACT FROM AUTHOR]

The localized compressive deformation (LCD) effect generated by an indentation process at the crack tip on the fatigue crack growth of the 7075-T651 aluminum alloy is reported. Eccentrically loaded single-edge crack tension specimens (ESE(T)) were pre-cracked at a crack length of about 20 mm by applying a constant amplitude fatigue loading. Subsequently, the LCD process was performed by using a semi-spherical indenter with a radius of 16 mm to compress the crack tip zone at different forces (5.0, 7.0, 12.5, 13.5, 15.5 kN), applied on the opposite surfaces of the specimens. The fatigue cracking process was continued on the compressed samples until an overall crack length of about 30 mm was obtained. The compressive load and the number of delayed cycles is discussed in terms of crack length and crack tip opening displacement (CTOD). A direct relationship between the compressive force induced by the LCD process and the delay of the crack propagation due to the crack arrest was observed. This effect became evident at a compressive force of 5.0 kN, where the crack propagation was arrested for about 9000 cycles in comparison with the non-LCD sample. However, when the force increased, the crack arrest also increased. The crack was considered to be completely arrested at a compressive load of 15.5 kN, since the crack did not grow after the application of more than 3 × 106 cycles. [ABSTRACT FROM AUTHOR]

Abstract: We consider the Schrödinger equation in the Thomas–Fermi field, a model that has been used for describing electron systems in -doped semiconductors. It is shown that the problem becomes exactly-solvable if a particular effective (position-dependent) mass distribution is incorporated. Orthogonal sets of normalizable bound state solutions are constructed in explicit form, and the associated energies are determined. We compare our results with the corresponding findings on the constant-mass problem discussed by Ioriatti (1990) [13]. [Copyright &y& Elsevier]

Background: There is a strong spatial correlation between demographics and chronic diseases in urban areas. Thus, most of the public policies aimed at improving prevention plans and optimizing the allocation of resources in health networks should be designed specifically for the socioeconomic reality of the population. One way to tackle this challenge is by exploring within a small geographical area the spatial patterns that link the sociodemographic attributes that characterize a community, its risk of suffering chronic diseases, and the accessibility of health treatment. Due to the inherent complexity of cities, soft clustering methods are recommended to find fuzzy spatial patterns. Our main motivation is to provide health planners with valuable spatial information to support decision-making. For the case study, we chose to investigate diabetes in Santiago, Chile. Methods: To deal with spatiality, we combine two statistical techniques: spatial microsimulation and a self-organizing map (SOM). Spatial microsimulation allows spatial disaggregation of health indicators data to a small area level. In turn, SOM, unlike classical clustering methods, incorporates a learning component through neural networks, which makes it more appropriate to model complex adaptive systems, such as cities. Thus, while spatial microsimulation generates the data for the analysis, the SOM method finds the relevant socio-economic clusters. We selected age, sex, income, prevalence of diabetes, distance to public health services, and type of health insurance as input variables. We used public surveys as input data. Results: We found four significant spatial clusters representing 75 percent of the whole population in Santiago. Two clusters correspond to people with low educational levels, low income, high accessibility to public health services, and a high prevalence of diabetes. However, one presents a significantly higher level of diabetes than the other. The second pair of clusters is made up of people with high educational levels, high income, and low prevalence of diabetes. What differentiates both clusters is accessibility to health centers. The average distance to the health centers of one group almost doubles that of the other. Conclusions: In this study, we combined two statistical techniques: spatial microsimulation and selforganising maps to explore the relationship between diabetes and socio-demographics in Santiago, Chile. The results have allowed us to corroborate the importance of the spatial factor in the analysis of chronic diseases as a way of suggesting differentiated solutions to spatially explicit problems. SOM turned out to be a good choice to deal with fuzzy health and socioeconomic data. The method explored and uncovered valuable spatial patterns for health decision-making. In turn, spatial microsimulation. [ABSTRACT FROM AUTHOR]

Un herbario es una colección de especímenes vegetales destinada al estudio y a la enseñanza de la Botánica. Consiste en un conjunto de plantas secas, debidamente organizadas, lo cual hace de este no solo una colección de ejemplares sino un centro de información sobre diferentes aspectos de las plantas y su clasificación. El herbario de la Universidad El Bosque HUEB, a lo largo de los últimos 3 años ha empezado a sufrir una remodelación y reestructuración dentro de lo cual se han empezado a crear colecciones de grupos botánicos con los que no se contaba o que tenían un número escaso de muestras, además se empezó reorganizar y enriquecer la colección de traqueófitos. La colección del HUEB actualmente incluye plantas vasculares (Licófitos, Monilófitos, Gimnospermas y Angiospermas), Briófitos (Hepáticas, Musgos y Antocerotes), Hongos (Basidiomicetos, Ascomicetos, Glomeromicetos, Zigomicetos y otros), Algas (Rodofitas, Clorofitas, Ocrofitas y otras) y Cianobacterias. El herbario HUEB tiene como objetivo mantener una colección de referencia de las prácticas académicas que impliquen la caracterización de vegetación o la identificación de material vegetal; de igual forma, en este deben reposar los ejemplares de referencia de material vegetal utilizado en los proyectos de aula y en los trabajos de grado. Además de la colección de referencia, el herbario incluye material que es utilizado con fines de docencia para los cursos de botánica básica y taxonomía vegetal del programa de Biología de la universidad El Bosque. La nueva estructura del herbario implicó la adquisición de un archivo móvil, dos estantes para exhibición de muestras, un horno de secado, un estereoscopio con brazo extensible y un escáner para el registro de los especímenes botánicos. Además de esto se desarrolló un manual de procedimientos que incluye todos los aspectos que se deben tener en cuenta durante la recolección de muestras, el prensado, el secado, el montaje y el etiquetado [1]. La colección cuenta actualmente con aproximadamente 5.000 especímenes, de los cuales, los grupos más representativos son plantas vasculares con 60% y hongos liquenizados con 22%. [ABSTRACT FROM AUTHOR]

Un herbario es una colección de especímenes vegetales destinada al estudio y a la enseñanza de la Botánica. Consiste en un conjunto de plantas secas, debidamente organizadas, lo cual hace de este no solo una colección de ejemplares sino un centro de información sobre diferentes aspectos de las plantas y su clasificación. El herbario de la Universidad El Bosque HUEB, a lo largo de los últimos 3 años ha empezado a sufrir una remodelación y reestructuración dentro de lo cual se han empezado a crear colecciones de grupos botánicos con los que no se contaba o que tenían un número escaso de muestras, además se empezó reorganizar y enriquecer la colección de traqueófitos. La colección del HUEB actualmente incluye plantas vasculares (Licófitos, Monilófitos, Gimnospermas y Angiospermas), Briófitos (Hepáticas, Musgos y Antocerotes), Hongos (Basidiomicetos, Ascomicetos, Glomeromicetos, Zigomicetos y otros), Algas (Rodofitas, Clorofitas, Ocrofitas y otras) y Cianobacterias. El herbario HUEB tiene como objetivo mantener una colección de referencia de las prácticas académicas que impliquen la caracterización de vegetación o la identificación de material vegetal; de igual forma, en este deben reposar los ejemplares de referencia de material vegetal utilizado en los proyectos de aula y en los trabajos de grado. Además de la colección de referencia, el herbario incluye material que es utilizado con fines de docencia para los cursos de botánica básica y taxonomía vegetal del programa de Biología de la universidad El Bosque. La nueva estructura del herbario implicó la adquisición de un archivo móvil, dos estantes para exhibición de muestras, un horno de secado, un estereoscopio con brazo extensible y un escáner para el registro de los especímenes botánicos. Además de esto se desarrolló un manual de procedimientos que incluye todos los aspectos que se deben tener en cuenta durante la recolección de muestras, el prensado, el secado, el montaje y el etiquetado [1]. La colección cuenta actualmente con aproximadamente 5.000 especímenes, de los cuales, los grupos más representativos son plantas vasculares con 60% y hongos liquenizados con 22%. [ABSTRACT FROM AUTHOR]

Abstract: Paleontological and historical stock abundance estimates indicate that pelagic fish populations inhabiting upwelling ecosystems undergo large interdecadal variations in abundance with amplitudes equal to, if not larger than, the interannual variability. The interdecadal variability is characterized by periods of high and low abundance, termed “pseudo-cycles”, because of their irregular periodicity. Fisheries targeting small pelagic fish suffer from overall overcapitalization, like many other fisheries, but also from an additional overcapitalization problem: a phase displacement between rapid fish population decreases and a slower disinvestment which follows. This lag produces economic hardship. Here we document the fish:fishery relationship for the Peruvian anchoveta. Anchoveta pseudo-cycles of 20 to >100 years are observed, with the present stock abundance most likely located near upper part of the cycle. Fleet overcapacity expressed as the proportion of unused present capacity is estimated at 72% and processing overcapacity at 89%. A simple bio-economic model demonstrates the risks associated with the pseudo-periodicity in fish stock abundance in conjunction with fishery investment, open access, and overcapacity: a timing bomb for the fishing sector. The lag between disinvestment and decrease in fish abundance is quantified. A reduction of the fishing and processing capacity and measures to decrease the investment lag are recommended to limit the social, economical and political tensions that will result from the expected decrease in stock abundance. Finally, some management options to reduce these risks are discussed. [Copyright &y& Elsevier]