Guano extraction in Atlantic Patagonia (1840–1880) Haller, Sofía Clara Between 1840 and 1880, multiple ships travelled towards the Atlantic coast of Patagonia, engaging in guano extraction. The Patagonian guano, though of inferior quality to the Peruvian product, was one of the most valuable coastal resources of the region. Drawing on a wide variety of documents and literature, the author has explored exploitation practices and logistics. 11 guano deposits exploited have been mapped and linked with details such as vessels, companies and harbours. The history of guano in the region shows an entanglement of connections and competition regarding the resource, raising inter-imperial disputes where different state and non-state agents operated to benefit both distant and regional economies.

Dysregulated light/dark cycle impairs sleep and delays the recovery of patients in intensive care units: A call for action for COVID-19 treatment Golombek, Diego Andrés; Pandi Perumal, Seithikurippu R.; Rosenstein, Ruth Estela; Lundmark, Per Olof; Spence, David Warren; Cardinali, Daniel Pedro; Reiter, Russel; Brown, Gregory M. Exposure to an adequate light–dark cycle is important for the speedy recovery of hospitalized and institutionalized patients. Light exposure, including natural light, offers several health benefits to both patients and nursing staff. This includes physical (e.g., decreased confusion and disorientation) and mental health benefits (e.g., prevention of depression) and a reduction in the hospital stay. Improved alertness and performance can also be noted among hospital staff. In this commentary, we discuss disrupting factors that 20 include light during the nighttime along with noise and physical procedures on the patient and others. We then address some of the important steps that can be undertaken to restore a more normal environment for patients in the intensive care unit, which can be particularly important for COVID-19 patients.

Producción de partículas virales pseudotipadas SARS-CoV-2 para la evaluación de nuevas terapias para COVID-19; Production of SARS-CoV-2 pseudotyped viral particles for the evaluation of new therapies against COVID-19 Etchevers, Lucas; Silvestrini, Paula; Velazquez, Natalia Soledad; Baravalle, María Eugenia; Renna, Maria Sol; Olmos Nicotra, Maria Florencia; Ortega, Hugo Hector; Marelli, Belkis Ester La inmunoterapia pasiva como tratamiento contra el virus SARS-CoV-2 (del inglés, severe acute respiratory syndrome coronavirus-2) requiere de la cuantificación de la capacidad neutralizante de los anticuerpos para el desarrollo de terapias efectivas. Para ello, es necesario el uso de partículas virales pseudotipadas no replicativas. Sin embargo, los reactivos de transfección necesarios para su producción son costosos y, en consecuencia, resulta una limitante al momento de escalar la producción. Una manera de eludir esta limitante es el uso de la polietilenimina (PEI), un polímero catiónico de bajo costo. El objetivo del trabajo consistió en optimizar un ensayo de transfección transitoria de bajo costo para producir pseudopartículas virales que expresen la proteína Spike del virus SARSCoV-2. Se realizaron ensayos de transfección en células HEK-293T evaluando diferentes concentraciones de PEI y tiempos de incubación. La transfección se evaluó mediante microscopía de epifluorescencia y citometría de flujo, mostrando que la condición de transfección que tiende a arrojar mejores resultados fue luego de 48 horas de incubación utilizando una relación 1/10 (ADNp/PEI). En conclusión, se ha logrado adaptar un protocolo para producir partículas lentivirales que expresan Spike utilizando un reactivo de transfección de bajo costo. Esto permitiría escalar la producción para, posteriormente, diseñar una plataforma para evaluar terapias para COVID-19.; Passive immunotherapy as a treatment against SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) requires to quantify neutralizing capacity of antibodies for development of effective therapies. However, the transfection reagents necessary for its production are expensive and, consequently, it is a limitation for the scaling up production. Using of polyethyleneimine (PEI), a lowcost cationic polymer, allows to avoid this. The objective of this work was to optimize a low-cost transient transfection assay to produce pseudoparticles that express the Spike protein of SARS-CoV-2. Transfection assays were performed in HEK-293T cells treated with different PEI concentrations and evaluating different incubation times. Transfection was assesed by epifluorescence microscopy and flow cytometry, showing that the transfection condition that tends to yield better results was after 48 hours of incubation using a 1/10 ratio (pDNA / PEI). In conclusion, it has been possible to adapt a protocol to produce spike-expressing lentiviral particles using a low-cost transfection reagent. This would allow to scale up the production and, following, to design a platform for evaluation of COVID-19 therapies.

La paleoherpetología en la Universidad de Buenos Aires: pasado y presente; Paleoherpetology at the Universidad de Buenos Aires: past and present Leardi, Juan Martín; Farina, Martin Ezequiel; Gomez, Raul Orencio; Marsicano, Claudia Alicia La Facultad de Ciencias Exactas y Naturales (FCEN) de la Universidad de Buenos Aires (UBA) se alojó inicialmente en la Manzana de las Luces de la Ciudad Autónoma de Buenos Aires, para luego reubicarse en los Pabellones I y II del complejo Ciudad Universitaria. Los estudios paleoherpetológicos en UBA se iniciaron con el Dr. Osvaldo Reig quien estuvo tres períodos en la institución: primero a fines de los 50, luego desde inicios a mediados de los 60 y finalmente a principios de los 80. Durante su primera época continuó con sus estudios de materiales fósiles de arcosaurios triásicos y anuros mesozoicos y cenozoicos. En su segundo período en la FCEN estuvo más enfocado en estudios microevolutivos basados en materiales actuales. La Dra. Ana María Báez se especializó en el estudio de los anfibios anuros, interactuando internacionalmente con destacados investigadores y formando profesionales en dicha temática y se desempeñó como profesora de la FCEN hasta el 2006. Tras su cese de actividades como profesora, este rol fue ocupado por su discípula la Dra. Claudia A. Marsicano, quien se dedicó al análisis de los anfibios temnospóndilos, aunque actualmente amplió sus estudios a las faunas de tetrápodos del Permo-Triásico de Gondwana. La Dra. C. A. Marsicano fundó el Laboratorio de Estudios Paleobiológicos en Ambientes Continentales y formó tesistas de grado y doctorado en paleoherpetología. En la actualidad los investigadores en paleoherpetología más jóvenes en la FCEN son Juan M. Leardi, que estudia crocodilomorfos, y Raúl O. Gómez, especializado en anuros y otros vertebrados.; The Facultad de Ciencias Exactas y Naturales (FCEN) of the Universidad de Buenos Aires (UBA) was originally located in the area of the Buenos Aires downtown known as the Manzana de las Luces and then was relocated to the buildings I and II of Ciudad Universitaria. The paleoherpetological studies in this institution began with the contributions of Dr. Osvaldo Reig, who was at UBA in three separate periods: first in the early ’50s, then during the earlies and mid ’60s, and finally in the mid ’80s. During his first period his research was focused on Triassic archosaurs and anurans from the Mesozoic and Cenozoic. On his second period at FCEN, his research was focused towards microevolutionary studies based on extant species. Dr. Ana María Báez is a specialist in fossil anurans, who had a high impact on the field and formed several students and acted as a professor at FCEN up to 2006. After A. M. Báez retired from her teaching duties, her place was filled by her disciple Dr. Claudia A. Marsicano. Dr. C. A. Marsicano centered her early studies on fossil temnospondyls to later expand her focus to the analyses of Permo-Triassic tetrapod faunas of Gondwana. C. A. Marsicano founded the Laboratorio de Estudios Paleobiológicos en Ambientes Continentales and has acted as advisor in several undergraduate and doctoral theses. The younger paleoherpetologists of the FCEN are Dr. Juan M. Leardi, whose research focuses in fossil crocodylomorphs, and Dr. Raúl O. Gómez, who studies fossil anurans and other vertebrates.

Silver nanoparticles synthesized by the heavy metal resistant strain Amycolatopsis tucumanensis and its application in controlling red strip disease in sugarcane Guerrero, Daiana Soledad; Bertani, Romina Priscila; Ledesma, Ana Estela; Frias, Maria de Los Angeles; Romero, Cintia Mariana; Dávila Costa, José Sebastián The production of bioethanol and sugar from sugarcane is an important economic activity in several countries. Sugarcane is susceptible to different phytopathogens. Over the last years, the red stripe disease caused by the bacterium Acidovorax avenae subsp. avenae produced significant losses in sugarcane crops. Bio-nanotechnology emerged as an eco-friendly alternative to the biosynthesis of antimicrobial molecules. The aims of this study were to (a) produce extracellular silver nanoparticles using the heavy metal resistant strain Amycolatopsis tucumanensis,(b) evaluate their antibacterial in vitro effect and (c) determine the potential of silver nanoparticles to protect sugarcane against red stripe disease. Amycolatopsis tucumanensis synthesized spherical silver nanoparticles with an average size of 35 nm. Nanoparticles were able to control the growth of A. avenae subsp. avenae in in vitro assays. In addition, in vivo assays in sugarcane showed a control upon the red stripe disease when silver nanoparticles were applied as preventivetreatment. The Disease Severity Index was 28.94% when silver nanoparticles were applied 3 days before inoculation with A. avenae subsp. avenae. To our knowledge, this is the first report of silver nanoparticles extracellularly synthesized by an Amycolatopsis strain that were able to inhibited the growth of A. avenae subsp. avenae and control the red stripe disease in sugarcane.

Quantitative matrix weighted estimates for certain singular integral operators Muller, Pamela Anahí; Rivera Ríos, Israel Pablo In this paper quantitative weighted matrix estimates for vector valued extensions of Lr′-Hörmander operators and rough singular integrals are studied. Strong type (p,p) estimates, endpoint estimates, and some new results on Coifman-Fefferman estimates assuming A∞ and Cp condition counterparts are provided. To prove the aforementioned estimates we rely upon some suitable convex body domination results that we settle as well in this paper.

TikTok, el salvavidas de la industria editorial Cuestas, Paula; Saez, Victoria La Feria del Libro de Buenos Aires reabre sus puertas después de tres años y la expectativa es inmensa: es el exorcismo con el que sueña la industria editorial argentina, una de las más golpeadas por la crisis económica y la pandemia. La esperanza descansa, principalmente, en el segmento que más lee y que mantuvo su amor por los libros a pesar del aislamiento: los y las jóvenes. Un grupo que crece día a día de la mano de tiktokers, youtubers, instagramers y bloggers.

Varieties with existentially definable factor congruences Badano, Mariana; Campercholi, Miguel Alejandro Carlos; Vaggione, Diego Jose We study the varieties with 0 → and 1 → where factor congruences are definable by existential formulas parameterized by central elements. This continues previous work on equational definability of factor congruences.

Registros paleobiogeográficos de graptoideos Floianos (Ordovícico Temprano) Registros de gaptolitos ordovícicos de la secciones de Muñayoc y Río Santa Rosa, provincia de Jujuy, y en otras regiones del mundo con el fin de realizar un análisis paleobiogeográfico.

Chaotic fluctuations in mitochondrial function under oxidative stress. Superoxide dismutatase (SOD2) concentrations of 0.013, 0.016,0.0164, 0.0216733 mM These chaotic time series of mitochondrial dynamics under conditions of oxidative stress are analyzed in detail in Kembro et al. 2018. Mitochondrial chaotic dynamics: Redox-energetic behavior at the edge of stability. Mitochondrial model used was described in the project overview and in detail (Kembro et al. 2013. Biophys J 104(2):332-343; Kembro et al., 2014. Front Physiol 5:257).

ECAUNGS La base de datos se centra en mediciones de material particulado y meteorología realizada con un equipo de bajo costo desarrollado denominado ECAUNGS. A su vez, se sincronizó con datos tomados con un fotómetro solar de bajo costo en la misma zona, y con meteorología descargada del SMN y de asimilación del NOAA, así como datos de contaminantes y meteorología de la estación de calidad de del aire en Dock Sud de ACUMAR. Esta base se utilizó para desarrollar un modelo de aprendizaje automático para predecir concentraciones de material particulado (Ver MÉTODOS DE BAJO COSTO PARA ESTUDIO PRELIMINAR DEL MATERIAL PARTICULADO EN EL CENTRO-NORTE DEL CONURBANO BONAERENSE, en Anales AFA 2022).

Planilla de sitios Planilla con sitios arqueológicos y sus características (sin curar)

Wildfire Smoke Effects on Lake-Habitat Specific Metabolism: Toward a Conceptual Understanding Scordo, Facundo; Sadro, Steven; Culpepper, Joshua; Seitz, Carina; Chandra, Sudeep The impacts of wildfire smoke on lake habitats remains unclear. We determined the metabolic response to smoke in the epi-pelagic and two littoral habitats in Castle Lake, California. We compared light regime, gross primary production, ecosystem respiration, and net ecosystem production in years with and without smoke. During the smoke period incident ultraviolet-B (UV-B) radiation and photosynthetically active radiation (PAR) decreased by 53% and 28%, respectively, while the water column extinction coefficient of UV-B and PAR increased by 20% and 18% respectively. Epi-pelagic productivity increased during smoke cover because of decreased solar inputs. PAR values remained sufficient to saturate productivity, suggesting observed differences were primarily the result of changes in UV-B. Littoral-benthic productivity did not change, possibly reflecting adaptation to high-intensity UV-B light in these habitats. Our results highlight the importance of understanding how prolonged wildfire smoke alters the amount of energy produced from specific habitats in lakes.

Actividad cuaternaria entre el piedemonte y la planicie orientales de la sierra de Comechingones asociada a la falla Santa Catalina, Sierras Pampeanas de Córdoba, Argentina; Quaternary activity associated with the Santa Catalina fault between the eastern piedemont and plain of the Comechingones mountain range, Sierras Pampeanas of Córdoba, Argentina Sagripanti, Guillermo Luis; Villalba, Diego; Andreazzini, María Jimena Las deformaciones neotectónicas asociadas al frente de levantamiento de la sierra de Comechingones se concentran en su piedemonte occidental, aunque también se han detectado deformaciones análogas vinculadas a fallas inversas ubicadas en el piedemonte oriental y en su límite con la planicie aledaña, entre estas fallas, las denominadas Las Lagunas y Las Rosas. El objetivo de la presente contribución es presentar evidencias neotectónicas que confirmen la actividad cuaternaria de la falla Santa Catalina situada al este de las antes mencionadas. Entre los métodos aplicados se destacan la toma de fotografías aéreas oblicuas, la descripción de perfiles naturales, un análisis de modelos de elevación digital, determinación de parámetros morfométricos en tramos de cauces y la utilización de información de perforaciones para la extracción de agua e información gravimétrica obtenida en un trabajo anterior. Los resultados indican que la falla Santa Catalina es una falla de movimiento inverso no emergente, responsable de la morfología que generan los mesobloques Santa Catalina-Golf y Espinillos, y de las modificaciones en la red de drenaje local. De acuerdo a las deformaciones detectadas, pliegues y flexuras, entre otras, se interpreta que la falla Santa Catalina ha tenido actividad durante el Cuaternario y que podría representar a las deformaciones neotectónicas más orientales de la provincia geológica “Sierras Pampeanas de Córdoba y San Luis” a los 33º S.; The neotectonic deformations associated with the uplift front of the Comechingones mountain range are concentrated in its western foothills, although analogous deformations associated with reverse motion faults located in the eastern foothills and on its border with the surrounding plain, such as the so-called Las Lagunas and Las Rosas, have also been detected. The objective of this contribution is to present neotectonic evidence confirming the quaternary activity of the Santa Catalina fault. Oblique aerial photos, description of natural profiles, a digital elevation models analysis, determination of morphometric parameters in river reaches and the use of drilling information for water extraction and gravimetric information obtained in previous works among others, were the applied methods. The results indicate that the Santa Catalina fault is a non-emergent reverse motion fault, responsible for the morphology generated by the Santa Catalina-Golf and Espinillos blocks, and for the modifications in the local drainage network. The deformations detected, folds and flexures among others, allow us to interpret that the Santa Catalina fault has been active during the Quaternary and that it could represents the easternmost neotectonic deformations of the geological province Sierras Pampeanas of Córdoba and San Luis to this latitude of 33º South.

Early-stage response in anaerobic bioreactors due to high sulfate loads: Hydrogen sulfide yield and other organic volatile sulfur compounds as a sign of microbial community modifications Olivera, Camila; Tondo, Maria Laura; Girardi, Valentina; Fattobene, Lucia; Herrero, María Sol; Perez, Leonardo Martin; Salvatierra, Lucas Matías In this work, the early-stage response of six lab-scale biogas bioreactors fed with different amounts of a sulfate-rich organic agro-industrial effluent was investigated. Biogas characterization, gas chromatography selective for sulfur compounds and high-throughput sequencing of 16S rRNA gene were performed. Hydrogen sulfide (H2S) yield went from transient to steady state in ∼ 2 weeks for all the studied conditions. In addition, volatile sulfur compounds (VSCs), like methanethiol (MeSH) and dimethyl sulfide (DMS), were generated at high sulfate loads. Changes were evidenced in the microbial community structures, with a higher abundance of genes involved in the dissimilatory sulfate-reduction pathway in high loaded sulfate bioreactors, as determined by PICRUSt analysis. Principal component analysis (PCA) and correlation analyses evidenced strong relationships between H2S, VSCs and the microbial community. Sulfate-reducing bacteria (SRB) like Desulfocarbo, Desulfocella and Desulfobacteraceae might be possibly linked with methylation processes of H2S.

El renacimiento del mundo antiguo en Italia: Diálogos y debates; The renaissance of the antiquity in Italy: Dialogues and debates Sverlij, Mariana Desde que Burckhardt encontrara en la cultura antigua resucitada en la Italia del siglo XIV una guía de acceso a los tiempos modernos, numerosos estudios han planteado sus propias certezas e interrogantes en torno al concepto de Renacimiento. Nuestra intención en las siguientes líneas es demorarnos en algunos de estos debates y diálogos historiográficos a fin de poner de relieve y en tensión la idea de retorno a un tiempo histórico-cultural anterior que subyace en el concepto de Renacimiento.; Since Burckhardt found a guide to access modern times through the Antiquity culture resurrected in fourteenth-century Italy, numerous studies have considered their own questions and notions surrounding the concept of Renaissance. In the following lines, it is intended to look into some of these historiographical debates and dialogues, with the aim to highlit and argue the idea of returning to a certain previous historical and cultural time, which underlies the concept of Renaissance.

Exp2GO: Improving Prediction of Functions in the Gene Ontology with Expression Data Di Persia, Leandro Ezequiel; Lopez, Tiago; Arce, Agustín Lucas; Milone, Diego Humberto; Stegmayer, Georgina The computational methods for the prediction of gene function annotations aim to automatically find associations between a gene and a set of Gene Ontology (GO) terms describing its functions. Since the hand-made curation process of novel annotations and the corresponding wet experiments validations are very time-consuming and costly procedures, there is a need for computational tools that can reliably predict likely annotations and boost the discovery of new gene functions. This work proposes a novel method for predicting annotations based on the inference of GO similarities from expression similarities. The novel method was benchmarked against other methods on several public biological datasets, obtaining the best comparative results. exp2GO effectively improved the prediction of GO annotations in comparison to state-of-the-art methods. Furthermore, the proposal was validated with a full genome case where it was capable of predicting relevant and accurate biological functions. The repository of this project withh full data and code is available at https://github.com/sinc-lab/exp2GO.

Caracterización morfo-fisiológica y respuesta germinativa de semillas de Delonix regia (Bojer) raf. sometidas a diferentes tratamientos pregerminativos; Morpho-physiological characterization and germinative response of Delonix regia (Bojer) raf seeds. subjected to different pregerminative treatments; Caracterização morfofisiológica e resposta germinativa das sementes de Delonix regia (Bojer) raf. sujeitas a diferentes tratamentos prégerminativos Luna, Claudia Verónica; Fontana, María Laura Delonix regia es una especie que adquirió importancia mundial debido a sus múltiples propiedades y aplicaciones. Esta presenta baja germinación por características propias de la semilla como: permeabilidad de la testa y presencia de inhibidores fenólicos que impide el flujo necesario de agua y oxígeno para desencadenarla. El objetivo del trabajo consistió en caracterizar la morfología y la respuesta germinativa de semillas de D. regia sometidas a diferentes tratamientos pregerminativos. Metodológicamente se aplicó un diseño experimental completamente al azar con cuatro repeticiones de 25 semillas cada uno. Los tratamientos fueron: escarificado físico, mecánico y combinado. En este contexto, se logró establecer la calidad de semillas indicando sus rasgos biométricos y caracterización colorimétrica, que son herramientas ventajosas para utilizarlas como sistemas de clasificación para la especie, ya que se ha determinado el tamaño y el color de las semillas más idóneas para obtener plántulas. En la evaluación de la calidad morfofisiológica de las simientes, se logró la interpretación de pruebas de viabilidad basados en patrones y detección de daños, por métodos destructivos y no destructivos. De los tratamientos pregerminativos considerados en esta investigación, el método de escarificado físico mediante la inmersión de las semillas por 15 minutos en agua a 100 ºC, con enfriamiento en agua a temperatura ambiente, ha influido de manera directa en la mayoría de los parámetros analizados para promover la emergencia de las plántulas.; Delonix regia is a species with a worldwide importance due to its multiple properties and applications. It has low the germination due seed characteristics like testa permeability and presence of phenolic inhibitors, which inhibits the necessary flow of water and oxygen to enhance the process. The objective of this study was to characterize the morphology and germination response of D. regia seeds subjected to different pregermination treatments. Methodologically, a completely randomized experimental design with four replicates of 25 seeds each was applied. The treatments were: physical, mechanical and combined scarification. In this context, it was possible to establish the quality of seeds by indicating their biometric traits and colorimetric characterization, which are advantageous tools to be used as classification systems for the species, since the size and color of the most suitable seeds for obtaining seedlings have been determined. In the assessment of the morphophysiological quality of the seeds, the interpretation of viability tests based on patterns and damage detection, by destructive and non-destructive methods, was achieved. Of the pregerminative treatments considered in this research, the physical scarification method by immersing the seeds for 15 minutes in water at 100 ºC, with cooling in water at room temperature, had a direct influence on most of the parameters analyzed to promote seedling emergence.; Delonix regia é uma espécie que adquiriu importância mundial devido a suas múltiplas propriedades e aplicações; mas apresenta deficiências na germinação de suas sementes; devido à variação no processo por suas características intrínsecas (problemas de permeabilidade do testa e presença de inibidores fenólicos), o que impede o fluxo necessário de água e oxigênio para desencadeá-lo. O objetivo deste estudo era caracterizar a morfologia e a resposta germinativa das sementes D. regia submetidas a diferentes tratamentos pré-germinativos. Metodologicamente, foi aplicado um projeto experimental completamente aleatório com quatro réplicas de 25 sementes cada. Os tratamentos foram: físicos, mecânicos e combinados de escarificação. Neste contexto, foi possível estabelecer a qualidade das sementes indicando seus traços biométricos e caracterização colorimétrica, que são ferramentas vantajosas para uso como sistemas de classificação das espécies, uma vez que o tamanho e a cor das sementes mais adequadas para a obtenção das mudas foram determinados. Na avaliação da qualidade morfofisiológica das sementes, foi feita a interpretação dos testes de viabilidade baseados em padrões e detecção de danos por métodos destrutivos e não-destrutivos. Dos tratamentos pré-germinativos considerados nesta pesquisa, o método de escarificação física por imersão das sementes durante 15 minutos em água a 100 ºC, com resfriamento em água à temperatura ambiente, teve uma influência direta na maioria dos parâmetros analisados para promover o surgimento de mudas.

Carbohydrate Metabolism in Bacteria: Alternative Specificities in ADP-Glucose Pyrophosphorylases Open Novel Metabolic Scenarios and Biotechnological Tools Bhayani, Jaina; Iglesias, María Josefina; Minen, Romina Inés; Cereijo, Antonela Estefanía; Ballicora, Miguel A.; Iglesias, Alberto Alvaro; Asención Diez, Matías Damián We explored the ability of ADP-glucose pyrophosphorylase (ADP-Glc PPase) from different bacteria to use glucosamine (GlcN) metabolites as a substrate or allosteric effectors. The enzyme from the actinobacteria Kocuria rhizophila exhibited marked and distinctive sensitivity to allosteric activation by GlcN-6P when producing ADP-Glc from glucose-1-phosphate (Glc-1P) and ATP. This behavior is also seen in the enzyme from Rhodococcus spp., the only one known so far to portray this activation. GlcN-6P had a more modest effect on the enzyme from other Actinobacteria (Streptomyces coelicolor), Firmicutes (Ruminococcus albus), and Proteobacteria (Agrobacterium tumefaciens) groups. In addition, we studied the catalytic capacity of ADP-Glc PPases from the different sources using GlcN-1P as a substrate when assayed in the presence of their respective allosteric activators. In all cases, the catalytic efficiency of Glc-1P was 1–2 orders of magnitude higher than GlcN-1P, except for the unregulated heterotetrameric protein (GlgC/GgD) from Geobacillus stearothermophilus. The Glc-1P substrate preference is explained using a model of ADP-Glc PPase from A. tumefaciens based on the crystallographic structure of the enzyme from potato tuber. The substrate-binding domain localizes near the N-terminal of an α-helix, which has a partial positive charge, thus favoring the interaction with a hydroxyl rather than a charged primary amine group. Results support the scenario where the ability of ADP-Glc PPases to use GlcN-1P as an alternative occurred during evolution despite the enzyme being selected to use Glc-1P and ATP for α-glucans synthesis. As an associated consequence in such a process, certain bacteria could have improved their ability to metabolize GlcN. The work also provides insights in designing molecular tools for producing oligo and polysaccharides with amino moieties.

Type II supernovae from the Carnegie Supernova Project-I: II. Physical parameter distributions from hydrodynamical modelling Martinez, Laureano; Bersten, Melina Cecilia; Anderson, J. P.; Hamuy, Mario; González Gaitán, S.; Förster, F.; Orellana, Mariana Dominga; Stritzinger, Maximilian; Phillips, M. M.; Gutiérrez, C. P.; Burns, C.; Contreras, C.; de Jaeger, T.; Ertini, Keila Yael; Folatelli, Gaston; Galbany, Lluís; Hoeflich, Peter; Hsiao, Eric; Morrell, Nidia Irene; Pessi, Priscila Jael; Suntzeff, Nicholas B. Linking supernovae to their progenitors is a powerful method for furthering our understanding of the physical origin of their observed differences while at the same time testing stellar evolution theory. In this second study of a series of three papers where we characterise type II supernovae (SNe II) to understand their diversity, we derive progenitor properties (initial and ejecta masses and radius), explosion energy, and 56Ni mass and its degree of mixing within the ejecta for a large sample of SNe II. This dataset was obtained by the Carnegie Supernova Project-I and is characterised by a high cadence of SNe II optical and near-infrared light curves and optical spectra that were homogeneously observed and processed. A large grid of hydrodynamical models and a fitting procedure based on Markov chain Monte Carlo methods were used to fit the bolometric light curve and the evolution of the photospheric velocity of 53 SNe II. We infer ejecta masses of between 7.9 and 14.8 M, explosion energies between 0.15 and 1.40 foe, and 56Ni masses between 0.006 and 0.069 M. We define a subset of 24 SNe (the gold sample) with well-sampled bolometric light curves and expansion velocities for which we consider the results more robust. Most SNe II in the gold sample (88%) are found with ejecta masses in the range of 810 M, coming from low zero-age main-sequence masses (912 M). The modelling of the initial-mass distribution of the gold sample gives an upper mass limit of 21.3{+3.8} {-0.4}M and a much steeper distribution than that for a Salpeter massive-star initial mass function (IMF). This IMF incompatibility is due to the large number of low-mass progenitors found when assuming standard stellar evolution. This may imply that high-mass progenitors lose more mass during their lives than predicted. However, a deeper analysis of all stellar evolution assumptions is required to test this hypothesis.