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En este trabajo indagamos el modo en que la ecología se dirige a su objeto de estudio, la naturaleza. “Ilustramos” este modo de estudiar la naturaleza mediante una crítica a la objetividad desarrollada por Theodore Roszak. Destacando que la ecología opera, en el contexto de la problemática ambiental, <> fuese objetiva. En este marco, problematizamos: (i) cómo se construye un significado de la naturaleza desde la ecología, (ii) cómo se silencia la experiencia del ecólogo en la naturaleza, (iii) cómo se da el vínculo entre valores (espirituales, estéticos o recreativos) y conocimiento ecosistémico y finalmente (iv) abordamos el carácter <> del conocimiento ecosistémico y su posición hegemónica en el contexto de la problemática ambiental. En líneas generales, las conclusiones del presente trabajo se dirigen a relegar al conocimiento ecosistémico a un lugar más modesto dentro de la actual crisis ambiental.

Abstract Mitogen-activated protein kinases 1 and 3 (MAPK1 and MAPK3), also called extracellular regulated kinases (ERK2 and ERK1), are serine/threonine kinase activated downstream by the Ras/Raf/MEK/ERK signal transduction cascade that regulates a variety of cellular processes. A dysregulation of MAPK cascade is frequently associated to missense mutations on its protein components and may be related to many pathologies, including cancer. In this study we selected from COSMIC database a set of MAPK1 and MAPK3 somatic variants found in cancer tissues carrying missense mutations distributed all over the MAPK1 and MAPK3 sequences. The proteins were expressed as pure recombinant proteins, and their biochemical and biophysical properties have been studied in comparison with the wild type. The missense mutations lead to changes in the tertiary arrangements of all the variants. The thermodynamic stability of the wild type and variants has been investigated in the non-phosphorylated and in the phosphorylated form. Significant differences in the thermal stabilities of most of the variants have been observed, as well as changes in the catalytic efficiencies. The energetics of the catalytic reaction is affected for all the variants for both the MAPK proteins. The stability changes and the variation in the enzyme catalysis observed for most of MAPK1/3 variants suggest that a local change in a residue, distant from the catalytic site, may have long-distance effects that reflect globally on enzyme stability and functions.

Desde la época en que emerge la problemática ambiental contemporánea, esta ha devenido en objeto de análisis e intervención tanto para la ecología (área de la biología) como para distintos organismos intergubernamentales de alcance mundial. En ambos ámbitos se han desarrollado una serie de marcos conceptuales dirigidos al abordaje de los cambios ecológicos, es decir, aquellas alteraciones que recaen sobre unidades que son objeto de estudio de la ecología. El objetivo de este trabajo es clarificar y contrastar los modos en que la ecología del disturbio (un reciente campo dentro de la ecología) y diferentes organismos intergubernamentales conceptualizan y abordan el cambio ecológico. Para ello, efectuamos una comparación analítica entre el concepto de ‘disturbio’ de la ecología y la noción de ‘driver’ proveniente de los organismos intergubernamentales. En la comparación, observamos que dichos conceptos buscan explicar procesos similares de cambio ecológico bajo una misma lógica causal, aunque manifiestan importantes diferencias en el tratamiento de las condiciones iniciales que permiten estudiarlos. Concluimos que la noción de ‘driver’ supone un empobrecimiento epistemológico en relación con el concepto de ‘disturbio’. Finalmente discutimos algunas implicancias de este problema epistemológico, dado que es la noción empobrecida de ‘driver’ la que se impone en el contexto internacional a la hora de explicar un cambio ecológico, materializándose en lineamientos reconocidos por naciones de todo el mundo que trasladan dicho empobrecimiento al terreno de las políticas públicas. Urge revisar en qué medida estamos contribuyendo a la construcción y reproducción de una problemática ambiental empobrecida epistemológicamente.

En Argentina, en el período 2019-2020 se experimentó el mayor brote de la historia del dengue en el país. Nuestro objetivo es comprender los sentidos que diferentes agentes de salud y vecinos y vecinas en un municipio de Buenos Aires le dan a la comunidad, a las diferencias de clases sociales, y a la presencia de migrantes, en relación con el dengue. Para esto, realizamos entrevistas semiestructuradas en 2021. Observamos que los y las agentes de salud recuperan las diferencias de clase social como un aspecto relevante para la intervención en dengue y mencionan dificultades de participación por parte de lo que denominan clases medias y altas. También encontramos que los y las agentes de salud asocian la movilidad de las y los migrantes con las epidemias de dengue. Sin embargo, en esta interpretación hay incertidumbres y se amplía al considerar otros factores.

El control biológico de especies no nativas que causan daños económicos y ambientales es la tecnología más importante de la Biología de las Invasiones. Si bien hay acuerdo que dicha tecnología es ambientalmente más amigable que el control químico, existen discusiones abiertas sobre los riesgos asociados a la misma. En el presente trabajo analizamos, utilizando como fuentes artículos científicos de revisión, las bases epistémicas subyacentes al desarrollo y la evaluación de riesgos asociados al control biológico. En particular, si sucede o no simplificación epistemológica y su vínculo con la subestimación de riesgos. El análisis muestra que suceden cuatro tipos interrelacionados de simplificación epistemológica: i) interacciones uno-a-uno de tipo fisiológicas, linealizadas y descontextualizadas entre agente de control y especies blanco o no-blanco; ii) predominancia de factores de niveles organísmico e infra-organísmico, en vinculación con teorías y conceptos de la Ecofisiología; lo que obvia interacciones, procesos y mecanismos que suceden a nivel de comunidad y ecosistemas, y los marcos teóricos de la Ecología asociados; iii) exclusión de mecanismos evolutivos relevantes como la adaptación y la plasticidad fenotípica post-introducción; y iv) restricción de temporalidades y espacialidades a aquellas de procesos fisiológicos y comportamentales del nivel organísmico o inferiores. Este escenario deriva en una subestimación, o directamente omisión, de riesgos ambientales como alteraciones potenciales que el evento de control biológico puede imponer sobre especies no-blanco y también sobre procesos y mecanismos comunitarios y ecosistémicos.

En este trabajo indagamos acerca de cómo las lógicas que impulsaron la creación de los primeros Parques Nacionales de Argentina, en el marco de la expansión del Estado-nación y el establecimiento del capitalismo en la región, continúan modelando los diseños actuales de conservación. Al respecto, nuestra hipótesis señala que a través de la implementación de nuevos Parques Nacionales se reproducen formas de pensar y relacionarse con el ambiente que, en lugar de brindar soluciones, en varios aspectos profundizan las problemáticas socioambientales. Para corroborar lo propuesto, revisamos el proceso de creación del Parque Nacional Nahuel Huapi, primero de Argentina, para luego ponerlo en relación con el diseño del Parque Nacional El Impenetrable, uno de los últimos en implementarse en el país. Tras analizar fuentes diversas, complementadas con instancias de observación participante, detectamos la continuidad de un abordaje fragmentario y la persistente negación de historias, relaciones y conocimientos propios de los mundos sobre los que recae la implementación de Parques Nacionales. Además, problematizamos sobre cómo las áreas naturales protegidas legitiman el modo de producción y la racionalidad utilitaria que condujeron a las crisis socioambientales actuales.

Objectives: To describe the sonographic features of the caudothalamic groove in the third trimester of pregnancy in a group of structurally normal fetuses and to report a small series of cases with abnormal appearance of the caudothalamic groove at antenatal cranial ultrasound. Methods: This was an observational study conducted at two fetal medicine referral units in Italy. A non‐consecutive cohort of pregnant women with a singleton non‐anomalous pregnancy were recruited prospectively and underwent three‐dimensional (3D) ultrasound assessment of the fetal brain at 28–32 weeks' gestation. At offline analysis, the ultrasound volumes were adjusted in the multiplanar mode, according to a standardized methodology, until the caudothalamic groove was visible in the parasagittal plane. To evaluate interobserver agreement, two operators were asked independently to indicate if the caudothalamic groove was visible unilaterally or bilaterally on each volume and Cohen's kappa (κ) coefficient was calculated. The digital archives of the two centers were also searched retrospectively to retrieve cases with abnormal findings at the level of the caudothalamic groove on antenatal cranial ultrasound that were confirmed postnatally. Results: A total of 180 non‐consecutive cases were included. At offline analysis of the 3D ultrasound volumes, the caudothalamic groove was identified in the parasagittal plane by both operators at least unilaterally in 176 (97.8%) cases and bilaterally in 174 (96.7%) cases. The κ‐coefficient for the agreement between the two independent operators in recognizing the caudothalamic groove was 0.89 and 0.83 for one and both hemispheres, respectively. The retrospective search of our archives yielded five cases with an abnormal appearance of the caudothalamic groove at antenatal cranial ultrasound, including two cases of hemorrhage and three cases of cyst. Conclusions: The caudothalamic groove is consistently seen in normal fetuses on multiplanar neurosonography in the third trimester, and abnormal findings in this region may be detected antenatally. © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

The poor preservation state of chitinozoans recovered from samples of the La Pola (Sandbian–Katian) and Don Braulio formations (Hirnantian-Llandovery), after being processed with standard methods, required significant modifications in processing. The sodium hexametaphosphate technique was used to avoid invasive mechanical procedures. Hence, more complete chitinozoans that preserved original features produced by biological, mechanical, and chemical degradation appeared. The processes that affected the good preservation of the chitinozoan exine are associated with factors inherent to the sedimentary environment, and biological and geological taphonomic effects that occurred in different regions of the Precordillera, added to the important associated tectonic activity. The thermal alteration was also an important factor in the fragile and brittle condition of the organic matter recovered. This transcends the preservation-processing technique relationship to be used. The results obtained from non-standard processing contribute to the paleoenvironmental interpretation of the Pola and Don Braulio successions, which are still widely discussed, and the determination of the most accurate age of the La Pola Formation. The latter will allow us to propose a biostratigraphic correlation between chitinozoan zones and graptolite zones, given the presence of both groups in the succession studied here, and to establish correlations with other successions in the Precordillera and elsewhere. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the interobserver agreement among midwives for the interpretation of intrapartum CTG traces, using both the 2015 FIGO guidelines and the physiology-based guidelines. Material and methods: Retrospective, single-center, observational study conducted at the Maternity Hospital of the University of Parma, Italy, between November 2022 and July 2023. We selected 100 nonconsecutive intrapartum CTG traces from women undergoing operative delivery (cesarean or instrumental vaginal delivery). Participating midwives received the last 60 min of CTG recording prior to the decision for an operative delivery was made. Five midwives with different professional experience classified the CTG tracing according to the 2015 FIGO guidelines and the physiology-based guidelines at the time of the decision for the operative delivery. Each midwife was categorized as senior or junior if her clinical experience was equal or more or less than 5 years. All participating midwives were blinded to the demographic and clinical variables of each case, as well as to the labor and neonatal outcome. The main outcome of the study was the interobserver agreement among the 5 midwives with either guideline. The secondary outcome was the interobserver agreement based on clinical experience. The agreement between the observers was estimated through the Krippendorff's alpha statistics. Results: The interobserver agreement for the interpretation of intrapartum CTG traces according to the 2015 FIGO guideline was in the upper limit of the "unacceptable" classification, with a Krippendorff's alpha of 0.632 (95% CI, 0.545–0.723). The interobserver agreement of the physiology-based CTG guideline was classified as "unacceptable" with a Krippendorff's alpha of 0.359 (95% CI, 0.125–0.582). The interobserver agreement among senior midwives according to the 2015 FIGO guidelines was considered as "tentative acceptable agreement" with a Krippendorff's alpha of 0.724 (95% CI, 0.636–0.805). Among junior midwives, the interobserver agreement according to the latter guideline was classified as "unacceptable" with a Krippendorff's alpha of 0.569 (95% CI, 0.359–0.751). Using the physiology-based guideline, the interobserver agreement of the senior midwives – Krippendorff's alpha 0.493 (95% CI, 0.320–0.623) – and "junior" midwives – Krippendorff's alpha 0.359 (95% CI, 0.100–0.581) – were considered both "unacceptable". Conclusions: Our study showed that intrapartum CTG interpretation is characterized by an overall unacceptable level of interobserver agreement among midwives, with the 2015 FIGO guidelines showing better agreement compared to physiology-based guidelines. The interpretation of intrapartum CTG by "senior" midwives using the 2015 FIGO guidelines showed the highest, interobserver agreement, indicating a "tentative acceptable agreement". [ABSTRACT FROM AUTHOR]

Desde la década de 1960, con el surgimiento de las problemáticas ambientales, el discurso hegemónico de la ecología es recibido, reproducido y amplificado por una amplia variedad de actores sociales. Aquí, analizaremos un aspecto que consideramos central de este discurso. Nuestro objetivo se dirige a indagar en qué medida la ecología recupera los dualismos y . Nuestra hipótesis de trabajo es que esta disciplina opera mediante un doble movimiento: mientras trae a primer plano el dualismo , simultáneamente, soslaya el dualismo . Bajo este doble movimiento, esperamos mostrar que el discurso ecológico logra despolitizar la naturaleza, relegando a la periferia diferentes formas de concebir el entorno. Nuestro enfoque epistemológico-metodológico descansará sobre una lógica de las distinciones, de aquí que trabajaremos sobre los dualismos mencionados, a partir de la distinción . Finalmente, presentaremos algunas consideraciones sobre el dominio del discurso ecológico y sobre la relevancia de una posición relativista en el contexto internacional de las problemáticas ambientales.

Background and aims: Taxonomic works of the modern pollen grains from the vegetation of the Iberá Wetlands from northeastern Argentina, and other areas of the Corrientes province, have mostly been carried out in last decade. However, very few of these taxonomic works include illustration of palynomorphs. The objective of this contribution is to provide the first morphological records of palynomorphs of angiosperms, ferns, lycophytes and bryophytes from sediments from the Holocene of the Iberá Wetlands. M&M: Core samples obtained by mean of a Livingston-type sampler from six lakes in their central and deepest parts on the western margin of the Iberá Wetlands were analyzed. Results: Fifty-five types of palynomorphs are described and illustrated: 46 pollen types correspond to 27 families of angiosperms and nine trilete spore-types to ferns, lycophytes and bryophytes. Information to differentiate local (species that form part of the natural vegetation of the Iberá Wetlands) and extra-local taxa (those that do not belong to the Iberá), that achieved to depocenters mostly by means of wind currents coming from farther regional vegetation, was included. Conclusions: Pollen grains and spores identifications up to species level enhances paleoenvironmental reconstructions based on more accurate ecologic information and geographical distribution. This work broadens the knowledge of the palynological flora of northeastern Argentina and it will contribute to differentiate the local vegetation from the extra-local in future paleocological and paleoenvironmental interpretations.

Abstract We present in this work a first X‐ray Absorption Spectroscopy study of the interactions of Zn with human BST2/tetherin and SARS‐CoV‐2 orf7a proteins as well as with some of their complexes. The analysis of the XANES region of the measured spectra shows that Zn binds to BST2, as well as to orf7a, thus resulting in the formation of BST2‐orf7a complexes. This structural information confirms the the conjecture, recently put forward by some of the present Authors, according to which the accessory orf7a (and possibly also orf8) viral protein are capable of interfering with the BST2 antiviral activity. Our explanation for this behavior is that, when BST2 gets in contact with Zn bound to the orf7a Cys15 ligand, it has the ability of displacing the metal owing to the creation of a new disulfide bridge across the two proteins. The formation of this BST2‐orf7a complex destabilizes BST2 dimerization, thus impairing the antiviral activity of the latter.