Reproductive and vegetative phenology of the micro endemic Stachytarpheta cassiae (Verbenaceae) Guimarães, Gesline Ferreira; Soares, Michellia Pereira; dos Santos, Renata Moreira; dos Santos, Fabíola Mendes; Ashworth, Lorena; Negreiros, Daniel; Aguilar, Ramiro; Fernandes, Geraldo Wilson Afonso The flora of the Brazilian rupestrian grasslands represents a hotspot of species richness and endemisms. Stachytarpheta cassiae (Verbenaceae), is a micro endemic species, from which nothing is known. Here, we quantified the activity and intensity of vegetative and reproductive phenophases throughout 12 months and tested for their seasonality and their relationship with local climatic variables. Both vegetative and reproductive phenophases were continuous. No seasonality was observed in the vegetative phenophases and none of them was influenced by climatic variables. Only flower buds and mature fruits’ intensities showed seasonality in February (rainy season) and July (dry season), respectively. Accordingly, increased temperature and humidity combined explained increased production of flower buds whereas decreased rainfall explained increased mature fruits. Higher intensity in flower buds may respond to similar climatic conditions as other species in the community. However, S. cassiae is much different as it continues producing flowers continuously. Higher intensity of mature fruits in the dry season is expected as their seeds are abiotically dispersed. Due to constant flower and leaf production, S. cassia may be a key species for the conservation of many vertebrate and invertebrate species and for maintaining the biogeochemical functioning of the impoverished soils of the rupestrian grasslands.

Ver el tiempo: la imagen óptico-sonora pura y su vinculación con el tiempo Aión en Gilles Deleuze; To see the time: the pure optical-sound image and its link with the Aion in Gilles Deleuze Matti, Felipe Andres Este trabajo tiene como objetivo investigar el vínculo entre la imagen óptico-sonora pura y el Aión. Para ello, se propone como hipótesis principal la situación óptica-sonora pura es el puntapié inicial para adquirir una imagen directa del tiempo. En efecto, dicha imagen sería la del Aión, base del tiempo cronológico. La situación óptico-sonora pura describe el momento en el que ya no hay percepción seguida de acción, dando lugar a la percepción de la interioridad del tiempo fundamental. Por lo tanto, se sostiene aquí que lo visto en la imagen óptico-sonora pura es el tiempo Aión o tiempo del acontecimiento.; : This paper aims to investigate the link between the pure optical-sound image and the Aion. For this purpose, it is proposed as a main hypothesis that the pure optical-sound situation is the starting point for acquiring a direct image of time. Indeed, this image would be that of the Aion, the basis of chronological time. The pure optical-sound situation describes the moment in which there is no longer perception followed by action, giving rise to the perception of the interiority of fundamental time. Therefore, it is argued here that what is seen in the pure optical-sound image is the Aion time or time of the event.

Cómo lidiar con el rechazo de un manuscrito científico Gracia, Guadalupe; Grande Ratti, Maria Florencia A raíz de un proyecto de investigación clínica, aprovechamos la oportunidad para normalizar el rechazo de un manuscrito científico ante su envío a revistas científicas arbitradas e indexadas. Comentamos lecciones aprendidas de nuestra experiencia, haciendo hincapié sobre los pasos para seguir a fin de superar satisfactoriamente el proceso editorial y alcanzar una publicación.

Tensiones productivas de un archivo teatral audiovisual: reflexiones a partir de una experiencia de gestión e investigación; Productive tensions of an audiovisual theatrical archive: reflections from a management and research experience Girotti, Bettina Inés; Brownell, Pamela El presente artículo parte de la experiencia que venimos realizando desde el Grupo de Estudio sobre Teatro contemporáneo, política y sociedad en América Latina (IIGG-UBA), con la creación y gestión de un archivo de registros audiovisuales dedicados a la temática delgrupo. Se trata del Fondo Documental Teatro y Política en América Latina (TyPAL), radicado en el Archivo Audiovisual del Instituto deInvestigaciones Gino Germani, y en esta ocasión, en el marco de la convocatoria de un dossier dedicado a temáticas de archivo vinculadas al arte y la literatura, nos interesa abordar algunas de las tensiones productivas que surgen del trabajo con el archivo y que están en gran medida concentradas en su definición como archivo teatral audiovisual. Estructuramos estas reflexiones en torno de algunos binomios que condensan esas tensiones productivas –investigación teatral/archivo; lo teatral/lo audiovisual; analógico/digital; archivos personales/archivos institucionales– y que nos permiten analizar algunas de los circunstancias específicas y discusiones conceptuales en las que se enmarca el TyPAL y que permiten abordar cuestiones propias de la investigación en artes escénicas en el contexto del creciente interés archivístico extendido en la cultura contemporánea.; This paper presents the experience of the research group on Contemporary Theater, Politics and Society in Latin America (IIGGUBA) with the creation and management of an archive that collects videos connected to the group’s subject. It is called TyPAL (Teatro y Política en América Latina) and it is hosted as a fonds inside the Audiovisual Archive of the Gino Germani Research Institute at the University of Buenos Aires. Within the framework of this issue’s dossier, we aim to approach some of the productive tensions that emerge when working with the archive, and that are connected to its definition as an audiovisual theatrical archive. We organized our reflections on a series of pairings that condense these productive tensions ‒theatrical research/archive; theatrical/ audiovisual; analogical/digital; personal archives /institutional archives‒ and that allowed us to analyze some of the specific circumstances and conceptual discussions in which the TyPAL is framed and that let us address issues of performing arts research in the context of the growing archival interest widespread in contemporary culture.

Acute and chronic physical activity improves spatial memory in an immersive virtual reality task Ramírez Butavand, Daniela; Rodríguez, María Florencia; Cifuentes, Maria Virginia; Miranda, Magdalena; Garcia Bauza, Cristian Dario; Bekinschtein, Pedro Alejandro; Ballarini, Fabricio Matias Physical activity benefits both fitness and cognition. However, its effect on long-term memory is unclear. In this study, we evaluated the effect of acute and chronic exercise on long-term spatial memory for a new virtual reality task. Participants were immersed in the virtual environment and navigated a wide arena that included target objects. We assessed spatial memory in two conditions (encoded targets separated by a short or long distance) and found that 25 min of cycling after encoding — but not before retrieval — was sufficient to improve the long-term memory retention for the short, but not for the long distance. Furthermore, we found that participants who engaged in regular physical activity showed memory for the short-distance condition whereas controls did not. Thus, physical activity could be a simple way to improve spatial memories.

A Fully Integrated, MEMS Based, Micro-Scale Printer for Cryogenic Thin Film Structures Lally, Richard W.; Imboden, Matthias; Stange, Alexander; Barrett, Lawrence K.; Perez, Diego Javier; Bishop, David J. Cryogenically produced thin film structures at the research scale facilitate many novels experiments. This paper discusses the construction of a fully integrated, MEMS based, printer, capable of printing micro and nano-scale features. In this millimeter-sized device, many features of a nanofab are incorporated to fabricate and characterize thin films in situ. The micro-scale printer comprises surface micromachined MEMS, digitally programmable source of atoms; a stencil lithograpghy tool that uses a MEMS nanopositioner for alignment; a substrate with on-chip leads for electrical characterization; a film thickness monitor; a substrate thermometer and heater. The device consists of three separate silicon die, flip-chip bonded to each other, forming a fully integrated, fabrication system of systems. This device creates micro and nano structures ranging from a few monolayers thick up to micron scale circuits. Applications range from searching for the Casimir Energy to the direct fabrication of quantum circuits, in situ, at cryogenic temperatures. [2022-0132]

Orogenic magmatism along the transition Precordillera-Sierras Pampeanas, between 29° and 31° S, Argentina Poma, Stella Maris; Ramos, Adriana Maria; Litvak, Vanesa Dafne; Quenardelle, Sonia Monica; Maisonnave, Emma Beatriz; Rubinstein, Nora Alicia New geochemical data and petrological analysis of Neogene volcanic units from the Pampean Flat Slab Segment (29°-31°SL) are presented in this contribution. Rocks were collected along a cross-section from the Western Sierras Pampeanas to the Eastern Precordillera. The outcrops delimit areas with a sub-parallel disposition to the orogenic front and main Andean regional structures. The study involves several volcanic rocks of the Formación Cerro Morado, sampled from the Huachi eruptive center and the Helvecia and Portezuelo de Los Burros mine districts, with thick lava flows and pyroclastic rocks. Lavas and breccias from several medium size outcrops near Huaco are also analyzed. To the NE, near the town of Guandacol, the Unidad Volcánica El Corral crops out. These rocks constitute the easternmost outcrops of the Precordillera in San Juan. We also studied rocks from the La Ciénaga volcano of the Sierra del Pocho Volcanic Field within the Sierras Pampeanas of Cordoba, which are the easternmost magmatic expression of the volcanic arc in this shallow subduction zone of the Central Andes. The new geochemical and isotopic data obtained from Formación Cerro Morado and lava flows belonging to the Unidad Volcánica El Corral, and its comparison with new geochemical data of the La Ciénaga volcano of the Sierra de Pocho show that these rocks result from the melting of two sources coming from two different types of crustal basements (Precordillera and Sierras Pampeanas). We found a magmatic association with similar geochemical features within the Formación Cerro Morado in Huachi region and Helvecia mine and Agua de Los Burros. It shows abundant hydrothermal fluids, which are often related to mineralization of economic interest. On the other hand, the rocks of the Formación Cerro Morado from Huaco, of the Unidad Volcánica El Corral and El Pocho Volcanic Field have a similar isotopic signature that allows us to infer the participation of the underlying Sierras Pampeanas Crust in their development. This feature leads us to interpret the continuity of the Sierras Pampeanas Basement Crust below the Western Precordillera.

Are scale leaves essencial in temperate-cold climates? An evaluation in tree species from temperate rainforests of South America Sosa, Claudia Maricel; Puntieri, Javier Guido The development of scaly buds (= cataphylls) has been traditionally associated with seasonally cold climates, although only few species from the southern hemisphere were investigated in this regard. The present work focuses on apical and axillary buds of seven tree species native to the South-American Temperate Rainforests (STR). Due to differences in the lineages from which these species derived, high levels of inter-specific variation in bud structure were expected. Apical and axillary buds were dissected under stereomicroscope, and the sizes of their parent shoots were evaluated. Cataphylls and leaf primordia were counted, and the presence of colleters and/or trichomes registered. Both intraand inter-specific variations in bud structure were found. The apical buds were scaly in two out of seven species, and naked in the other species. Axillary buds were scaly in all but one species. In general terms, larger shoots developed buds with more organs. The presence of colleters (in four species) was not restricted to those buds lacking an outer cover of cataphylls. Further studies should focus on the relevance at a broader scale of colleters and trichomes as protective structures in tree buds.

Geographic distribution notes: Amphisbaena kingii Escudero, Paula Cecilia; Avila, Luciano Javier Citamos una nueva localidad para Amphisbaena kingii en la margen sur del Rio Chubut, extendiendo su distribución casi 100 km al S de las previamente conocidas.

Microfluidic Platform Integrated with Carbon Nanofibers-Decorated Gold Nanoporous Sensing Device for Serum PSA Quantification Felici, Carlos Emiliano; Regiart, Daniel Matias Gaston; Pereira, Sirley Vanesa; Ortega, Francisco G.; Angnes, Lúcio; Messina, Germán Alejandro; Fernández Baldo, Martín Alejandro Prostate cancer is a disease with a high incidence and mortality rate in men worldwide. Serum prostate-specific antigens (PSA) are the main circulating biomarker for this disease in clinical practices. In this work, we present a portable and reusable microfluidic device for PSA quantification. This device comprises a polymethyl methacrylate microfluidic platform coupled with electrochemical detection. The platinum working microelectrode was positioned in the outflow region of the microchannel and was modified with carbon nanofibers (CNF)-decorated gold nanoporous (GNP) structures by the dynamic hydrogen bubble template method, through the simultaneous electrodeposition of metal precursors in the presence of CNF. CNF/GNP structures exhibit attractive properties, such as a large surface to volume ratio, which increases the antibody’s immobilization capacity and the electroactive area. CNFs/GNP structures were characterized by scanning electron microscopy, energy dispersive spectrometry, and cyclic voltammetry. Anti-PSA antibodies and HRP were employed for the immune-electrochemical reaction. The detection limit for the device was 5 pg mL−1, with a linear range from 0.01 to 50 ng mL−1. The coefficients of variation within and between assays were lower than 4.40%, and 6.15%, respectively. Additionally, its clinical performance was tested in serum from 30 prostate cancer patients. This novel device was a sensitive, selective, portable, and reusable tool for the serological diagnosis and monitoring of prostate cancer.

Effect of ligand concentration and ultrasonic treatment on inclusion complexes of high amylose corn starch with chia seed oil fatty acids Di Marco, Andrea Esther; Ixtaina, Vanesa Yanet; Tomás, Mabel Cristina Chia seed oil is rich in α-linolenic and linoleic fatty acids, which have multiple health benefits but are prone to oxidation due to their high degree of unsaturation. The linear component of starch, amylose, can interact with hydrophobic molecules (ligand) forming amylose inclusion complexes, which may potentially act as delivery systems of polyunsaturated fatty acids. Their physicochemical and functional properties are influenced by the conditions of formation. In the present study, it was investigated the effect of ultrasonic treatment and different ligand/starch ratios (10, 20, and 30% w/w) on the physicochemical properties of inclusion complexes formed between high amylose corn starch and enzymatically hydrolyzed chia seed oil. The increase in ligand/starch ratio, especially from 10 to 20%, yielded complexes with a higher content of α-linolenic acid. The effect of ultrasonic treatment on the acidic composition of complexes depended on the initial ligand concentration. All samples displayed a V-type X-ray diffraction pattern, indicating an effective complexation. Ultrasonically treated complexes showed a higher crystallinity than the untreated ones, suggesting that sonication promoted the fatty acid complexation. All samples displayed the same thermal behavior (Tp > 90 °C, ΔH = 7 J/g) and similar structural properties at the microscopic level. Thermogravimetric analysis showed that the untreated complexes formed with a 10% ligand/starch ratio effectively protected hydrolyzed chia seed oil from oxidative deterioration, suggesting an appropriate behavior as potential carrier agents of fatty acids from chia seed oil in food.

Ordovician stratigraphy and biota of Mexico Cuen Romero, Francisco Javier; Buitrón-Sánchez, Blanca Estela; Beresi, Matilde Sylvia; Palafox Reyes, Juan J.; Monreal, Rogelio In Mexico, Ordovician sedimentary rocks are exposed in the states of Baja California, Sonora, Chihuahua and Oaxaca, comprising approximately 30 stratigraphic successions ranging from Lower to Upper Ordovician. The ages of the sequences have been established primarily by utilizing conodonts and graptolites, which have also allowed us to differentiate between platform and oceanic basin environments. The State of Sonora has the most complete Ordovician stratigraphic sequences, ranging from Tremadocian to Hirnantian. The deposits in Baja California are Floian in age, while the sequences of Chihuahua range from Sandbian to Katian, and the deposits in Oaxaca are Tremadocian. The Ordovician deposits of northern Mexico (Baja California, Sonora, and Chihuahua) present a palaeogeographic relationship to the North American craton, mainly owing to faunal interspecific affinities, while the southern deposits (Oaxaca) are controversial due to the high degree of endemism of the faunas; however, they show affinity with Gondwana, Baltica and Avalonia, with a possible insular origin. The biotic assemblages of the Ordovician of Mexico include a variety of taxa, including algae, poriferans, corals, bryozoans, brachiopods, molluscs, trilobites, echinoderms, graptolites and conodonts as predominant elements. Despite many years of field studies in Mexican Ordovician localities, biostratigraphic correlations are insufficient and incomplete or based on limited interpretations. Thus, the Ordovician biostratigraphic data from Mexico compiled in the present paper have great potential and significant value. The advancement in the knowledge of the Ordovician biostratigraphy of Mexico will contribute to a major understanding of the relationships with the Ordovician System on a continental scale. Future advances will come mainly through increasing the amount and quality of data and improving bio-correlations among the Ordovician sequences of Mexico.

Microencapsulation of Probiotics with Soy Protein Isolate and Alginate for the Poultry Industry Babot, Jaime Daniel; Argañaraz Martínez, Fernando Eloy; Apella, Maria Cristina; Perez Chaia, Adriana Beatriz Many probiotic products, with properly selected microorganisms, may not be effective for the intended purpose due to the low tolerance of microorganisms to gastrointestinal digestion. The microencapsulation seems to be one of the most promising techniques to protect probiotics against adverse environmental conditions. Therefore, the aim of this work was the design of soy protein isolate-alginate microcapsules for the encapsulation of probiotics for the poultry industry by the water-in-oil emulsion technique. To this end, the strain Ligilactobacillus salivarius CRL2217, with the ability to bind wheat germ agglutinin (WGA) on its surface and protect intestinal epithelial cells from the cytotoxicity of the glycoprotein, was used as model microorganism. Several parameters were varied in order to find the better conditions for microencapsulation: oil source and nature, SPI and sodium alginate concentration, stirring equipment and time for emulsion formation, CaCl2 concentration, and absence or presence of stirring after the addition of the CaCl2 solution. The survival of entrapped cells to a simulated gastric digestion and their survival and release during simulated intestinal digestion were also investigated. The obtained particles effectively protected L. salivarius CRL2217 from the proteolytic activity and low pH present in the gastric environment. Besides, their content was released in contact with a simulated intestinal juice, as viable counts and binding of WGA after a simulated intestinal digestion revealed. This work paves the way for the design of probiotic supplements for poultry including gastrointestinal digestion-susceptible bacteria.

La función de policía hacia el gobierno político-administrativo. Mendoza, Río de la Plata, 1820-1828; The police function towards the political-administrative government. Mendoza, Río de la Plata, 1820-1828 Molina, Eugenia Rosa Ana Existe cierto consenso historiográfico respecto de la configuración de espacios políticos a partir de la jurisdicción de las ciudades indianas en el periodo que siguió a la desintegración de las Provincias Unidas del Río de la Plata. En ese contexto, la eliminación de los cabildos habría resultado clave porque permitió que los ejecutivos terminaran de incorporar la función de policía antes detentada por estos. Utilizar a esta última como vía de abordaje puede permitir analizar cómo se configuró progresivamente un ejercicio gubernamental cada vez menos declarativo, en el sentido jurisdiccional de respetar y reproducir un orden indisponible a través de un gobierno de jueces, y más político-administrativo, en tanto fundaba la capacidad de intervención sobre la vida social en la consecución del bien público.

Fablar y sonar curso rimado por la cuaderna vía: la Cantiga de Santa María 420; Fablar and sonar curso rimado in the cuaderna vía: the Cantiga de Santa María 420 del Rio, María Gimena; Rossi, Germán Pablo El verso alejandrino es uno de los metros más usados en la poesía medieval castellana. Contemporáneo a otros ligados al ámbito de la lírica trovadoresca, fue históricamente estudiado en lo que respecta a la articulación del mester de clerecía y, por ende, abordado sin establecer relaciones formales con otro tipo de producción poética. Es nuestra intención vincularlo aquí a la compilación lírica medieval surgida en torno a Alfonso X, las Cantigas de Santa María, con especial interés en la forma métrico-estrófica y en el contenido y melodía de la cantiga 420, pieza que se transmite en un único manuscrito mariano, el códice de los músicos (E). Editada por Walter Mettman en seis estrofas de doce versos, creemos que cabe revisar su estructura formal partiendo de una divisio estrófica tripartita alrededor de diferentes núcleos temáticos relacionados con el relato de su vida de la Virgen María en los evangelios apócrifos. Desde lo filológico, esta propuesta nos dejaría ante un claro ejemplo de uso de la cuarteta monorrima de alejandrinos en cuaderna vía en el corpus alfonsí. El cruce interdisciplinario con la musicología nos permitiría, a su vez, dar cuenta de la organización y las características del material melódico de la cantiga con el objeto de analizar su complementariedad con la estructura formal. Estos datos sonoros posibilitan que el texto de carácter narrativo de la cantiga pueda destacarse dada la redundancia sonora y la relación de predominancia silábica con que cuenta la melodía conservada en el códice alfonsí. *Nota: Soy la editora de este volumen especial de Olivar.; The alexandrine is one of the most used verse meters in Hispanic Medieval Lyrical Poetry. In this article we analyze the use of the alexandrine verse in the medieval lyric compilation ordered by Alfonso Xth, the Cantigas de Santa María. We are especially interested in the metric-strophic form, and in the content and melody of the CSM 420, a cantiga copied in one single Marian manuscript also known as the Musicians Codex (E). The poem was edited by Walter Mettman in six strophes of twelve verses. Mettman followed strictly the mise en page of E. We consider that his proposal can be revised under the lens of a coordinated philological and musicological approach in which we can subdivide its long stanzas in shorter quartets of alexandrine verses that relate to the biblical apocrypha. The interdisciplinary approach between Philology and Musicology also allowed us to account for the organization and characteristics of the melodic material of the cantiga in order to analyze its relationship with the formal structure. Consequently, we revisit its formal structure and propose a divisio based on the different topics that also relate to the melodic and formal structure of the cantiga.

Ensemble based methods for leapfrog integration in the simplified parameterizations, primitive‐equation dynamics model Nino Ruiz, Elias D.; Consuegra Ortega, Randy S.; Lucini, María Magdalena This paper presents efficient and practical implementations of sequential dataassimilation methods for the Simplified Parameterizations, primitive-EquationDYnamics (SPEEDY) Model, a well-known numerical model, into the dataassimilation community for climate prediction. In the SPEEDY model, the timeevolution of dynamics is performed via the second-order Leapfrog integrationscheme; this time integrator relies on two steps: the position and the velocity. Thecomputational implementation of SPEEDY blends the time integrator and thespatial discretization of dynamics to accelerate algebraic computations. Thus,there is no access to the right-hand side function of the ordinary differentialequations governing the time evolution of model dynamics. Consequently, theSPEEDY model is often treated as a black box wherein positions and velocitieswork as inputs and outputs. Since observations in operational data assimilationonly match position states, we can exploit augmented vector states to propagateanalysis innovations frompositions to velocities. For this purpose, we formulatethree variants of ensemble-based filters and perform numerical experiments toassess their accuracies.We consider two scenarios for the experiments: an idealcase wherein positions and velocities can be observed and a more realistic onewherein measurements are only accessible for position states. Besides, we discussthe effects of the ensemble size on the accuracies of our formulations and,even more, the typical case in which velocities are not updated across assimilationsteps. The results reveal that all filter formulations? accuracies remainthe same in terms of Root-Mean-Square-Error by neglecting observations fromvelocities (a realistic scenario) even for cases wherein the number of measurementsdecreases to 6% of model components. Furthermore, for all discussedfilter implementations, the propagation of analysis increments from positionto velocities improves up to 100% the performance of filter implementationswherein velocities are not updated, a typical operational scenario.

PHANGS-JWST First Results: Dust-embedded Star Clusters in NGC 7496 Selected via 3.3 μm PAH Emission Rodriguez, Maria Jimena; Lee, Janice C.; Whitmore, B.C.; Thilker, David A.; Maschmann, Daniel; Chandar, Rupali; Deger, Sinan; Boquien, Médéric; Dale, Daniel A.; Larson, Kirsten L.; Williams, Thomas G.; Kim, Hwihyun; Schinnerer, Eva; Rosolowsky, Erik; Leroy, Adam K.; Emsellem, Eric; Sandstrom, Karin M.; Grasha, Kathryn; Watkins, Elizabeth J.; Barnes, Ashley. T.; Sormani, Mattia C.; Kim, Jaeyeon; Anand, Gagandeep S.; Chevance, Mélanie; Bigiel, F.; Klessen, Ralf S.; Hassani, Hamid; Liu, Daizhong; Cao, Yixian; Pessa, Ismael; Kreckel, Kathryn; Egorov, Oleg V. The earliest stages of star formation occur enshrouded in dust and are not observable in the optical. Here we leverage the extraordinary new high-resolution infrared imaging from JWST to begin the study of dust-embedded star clusters in nearby galaxies throughout the Local Volume. We present a technique for identifying dust-embedded clusters in NGC 7496 (18.7 Mpc), the first galaxy to be observed by the PHANGS-JWST Cycle 1 Treasury Survey. We select sources that have strong 3.3 μm PAH emission based on a F300M − F335M color excess and identify 67 candidate embedded clusters. Only eight of these are found in the PHANGS-HST optically selected cluster catalog, and all are young (six have SED fit ages of ∼1 Myr). We find that this sample of embedded cluster candidates may significantly increase the census of young clusters in NGC 7496 from the PHANGS-HST catalog; the number of clusters younger than ∼2 Myr could be increased by a factor of 2. Candidates are preferentially located in dust lanes and are coincident with the peaks in the PHANGS-ALMA CO (2-1) maps. We take a first look at concentration indices, luminosity functions, SEDs spanning from 2700 Å to 21 μm, and stellar masses (estimated to be between ∼104 and 105 M ⊙). The methods tested here provide a basis for future work to derive accurate constraints on the physical properties of embedded clusters, characterize the completeness of cluster samples, and expand analysis to all 19 galaxies in the PHANGS-JWST sample, which will enable basic unsolved problems in star formation and cluster evolution to be addressed.

Two phosphoenolpyruvate carboxykinases with differing biochemical properties in Chlamydomonas reinhardtii Torresi, Florencia; Rodriguez, Fernanda Mariana; Gomez Casati, Diego Fabian; Martín, Mariana Phosphoenolpyruvate carboxykinase (PEPCK) catalyses the reversible reaction of decarboxylation and phosphorylation of oxaloacetate (OAA) to generate phosphoenolpyruvate (PEP) and CO2 playing mainly a gluconeogenic role in green algae. We found two PEPCK isoforms in Chlamydomonas reinhardtii and we cloned, purified and characterised both enzymes. ChlrePEPCK1 is more active as decarboxylase than ChlrePEPCK2. ChlrePEPCK1 is hexameric and its activity is affected by citrate, phenylalanine and malate, while ChlrePEPCK2 is monomeric and it is regulated by citrate, phenylalanine and glutamine. We postulate that the two PEPCK isoforms found originate from alternative splicing of the gene or regulated proteolysis of the enzyme. The presence of these two isoforms would be part of a mechanism to finely regulate the biological activity of PEPCKs.

New insights into the Piedra de Afilar Formation, Canelones department of Uruguay: Very-low-grade metamorphism, pressure solution, and age Dristas, Jorge Anastasio; Masquelin, Henri; Wemmer, Klaus; Bianchi, Franco Denis; Martinez, Juan Cruz; Massonne, Hans Joachim A detailed microstructural, mineralogical, and geochronological study was carried out along a profile in the Piedras de Afilar Formation (PAF) at the González quarry and surroundings (Uruguay). Both the PAF and the Soca granite were affected by very-low-grade metamorphism and pressure-induced dissolution. These postdiagenetic processes resulted in intense corrosion and alteration indicated by sericitization, silicification, and crystallization of iron oxides. Major auto-metamorphism was identified between the intrusive gabbro and the PAF, with almost no effects on the wall rock. K-Ar ages of sericite indicate 609-604 Ma for the metamorphism and related pressure-solution in the PAF. This age is in agreement with the juxtaposition of the Edén or Nico Pérez terranes and the Piedra Alta Terrane along the Sarandí del Yí shear zone. K-Ar dating of the gabbro wall rock constrained a deposition age of the PAF between 1000 and ca. 734 Ma.

Skyrmion fluid and bimeron glass protected by a chiral spin liquid on kagome Rosales, Hector Diego; Gómez Albarracín, Flavia Alejandra; Pujol, Pierre; Jaubert, L. Skyrmions are of interest both from a fundamental and technological point of view, due to their potential to act as information carriers. But one challenge concerns their manipulation, especially at high temperature where thermal fluctuations eventually disintegrate them. Here we study the competition between skyrmions and a chiral spin liquid, using the latter as an entropic buffer to impose a quasi-vacuum of skyrmions. As a result, the temperature becomes a knob to tune the skyrmion density from a dense liquid to a diluted gas, protecting the integrity of each skyrmion from paramagnetic disintegration. With this additional knob in hand, we find at high field a topological spin glass made of zero- and one-dimensional topological defects (resp. skyrmions and bimerons).