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Efforts to naturally remove atmospheric CO2 demand that largely intact forests be maintained. Our inter-cultural research initiative tested the hypothesis that Indigenous custody of the land is compatible with the maintenance of intact forests. Here we combined traditional knowledge, phytolith analysis, remote sensing, and tree inventories to study old-growth forests in Panama's Darién. Phytoliths served to elucidate historical vegetation, remote sensing revealed the current and past Indigenous footprints while tree stature and identity characterised the forest. Until now there has been very little to no human impact within these forests and current Indigenous footprint is both small and stable. Large trees accounted for 13% of trees in the plots that we established. For over half of the species, the measured tree height was taller than previously published maximum heights, leading us to conclude that these forests are a truly exceptional ecological refugium. Noting that the local communities are not rewarded for their custody of these exceptional forests we call to revisit the Good Practice Guidance for Land Use Land Use Change and Forestry to include intact forest land. In the context of sub-optimal carbon finance options, we also propose matching as a methodology that could prove additionality of forest conservation initiatives in climate mitigation portfolios.

Atmosphere-ocean interactions are particularly strong along the Chile-Peru coast and largely account for the extreme aridity of the Atacama Desert. Near the center of the driest part of this coastal desert, we found that the embayment Bahía Mejillones constitutes an unusually favorable setting for the formation and subsequent preservation of a sedimentary record of the successive oceanographic conditions of the last few thousand years. This work deals with relative abundance of various bio-indicators, including fish scales, foraminifers and phytoplankton, with a centimetre-scale resolution, in several gravity cores taken from 80 to 120 m depth, in a low-oxygen environment. We use this information to document ocean-climate changes at decadal to centennial time scales in the region. Radiocarbon dating on the bulk organic-rich sediment provides the chronological framework for the observed paleoceanographic changes. We interpret that an episode of relatively warmer water, with a stratified water column and enhanced anoxic (< 0.1 ml l-1O2) conditions at the bottom of the bay, might correlate with the Warm Medieval Interval (11th-15th centuries) of the northern hemisphere. A younger episode, characterised by cooler water, richer in planktonic foraminifers and anchovy remains, with dysoxic (0.1 to 0.3 ml l-1O2) or suboxic (> 0.3 ml l-1 O2) conditions at the bottom of the water column, may correspond to the Little Ice Age (16th to mid-19th centuries). During the first millennium of our era, two thin sedimentary layers which present similarities with the bed assigned to the warm episode are interpreted as possible remnants of very strong, or " mega " El Niño events. The study confirms that Bahía Mejillones sediments did record ocean-climate changes with a very high time-resolution, and thus deserve a closer attention to investigate the ocean-atmosphere interactions over the last few thousand yearsLas interacciones océano-atmósfera son particularmente fuertes a lo largo de la costa de Chile y Perú y explican en gran parte la extrema aridez del desierto de Atacama. Cerca del sector más seco del desierto costero, hemos encontrado que la bahía semi-cerrada de Bahía Mejillones constituye un sitio particularmente favorable para la formación y subsecuente preservación de registros sedimentarios de las condiciones oceanográficas sucesivas de los últimos miles de años. Este estudio analiza la abundancia relativa de varios bioindicadores, incluyendo escamas de peces, foraminíferos y fitoplancton, con una resolución de un centímetro, en muestras de testigos de gravedad obtenidas desde los 80 a 120 m de profundidad, en un ambiente muy pobre en oxígeno. Luego, se utiliza esta información para documentar cambios océano-climáticos en escalas decenales a seculares en la región. Fechamientos por radiocarbono, realizados sobre el componente orgánico del sedimento, proveen el marco cronológico para los cambios paleoceanográficos observados. Interpretamos que un episodio caracterizado por temperaturas relativamente cálidas, con una columna de agua estratificada y condiciones reforzadas de anoxia (< 0,1 ml l-1O2) en el fondo de la bahía, podría ser coetáneo con el Intervalo Cálido Medieval (siglos XI-XV) del hemisferio norte. Un episodio más reciente, caracterizado por aguas frías, rico en foraminíferos planctónicos y remanentes de anchoveta, con condiciones disóxicas (0,1 to 0,3 ml l-1O2) o subóxicas (> 0,3 ml l-1 O2) en la base de la columna de agua, podría corresponder a la "Pequeña Edad del Hielo" (siglo XVI a mediados del s. XIX). Durante el primer milenio de nuestra era, dos delgadas capas sedimentarias que presentan similitudes con la capa atribuída al episodio cálido son interpretadas como manifestaciones probables de eventos El Niño de intensidad muy fuerte (o "mega" El Niño). El estudio confirma que los sedimentos de Bahía Mejillones registraron efectivamente cambios oceano-climáticos con una resolución temporal muy alta, y en consecuencia, ameritan una mayor atención para investigar las interacciones atmósfera-océano durante los últimos miles de años

BackgroundHematopoietic cell transplantation (HCT) increases survival for acute leukemia. Outpatient allogeneic HCT reduces costs and increases transplant rates in developing countries. We report outcomes of outpatient HLA-identical and haploidentical HCT in acute leukemia.MethodsThis single-center retrospective cohort study analyzed 121 adult patients with acute myeloblastic (AML) and acute lymphoblastic leukemia (ALL) receiving an outpatient allogeneic HCT with peripheral blood allografts after reduced-intensity conditioning (RIC) from 2012-2022.ResultsThere were 81 (67%) haploidentical and 40 (33%) HLA-identical transplants. Complete chimerism (CC) at day +100 was not different in HLA-identical compared to haploidentical HCT (32.5% and 38.2%, P=0.054). Post-HCT complications, including neutropenic fever (59.3% vs. 40%), acute graft-versus-host-disease (aGVHD) (46.9% vs. 25%), cytokine release syndrome (CRS) (18.5% vs. 2.5%), and hospitalization (71.6% vs 42.5%) were significantly more frequent in haploidentical HCT. Two-year overall survival (OS) was 60.6% vs. 46.9%, (P=0.464) for HLA-identical and haplo-HCT, respectively. There was no difference in the 2-year disease-free-survival (DFS) (33.3% vs. 35%, P=0.924) between transplant types. In multivariate analysis, positive measurable residual disease (MRD) at 30 days (HR 8.8, P=0.018) and 100 days (HR 28.5, P=0.022) was associated with lower OS, but not with non-relapse mortality (NRM) (P=0.252 and P=0.123, univariate). In univariate analysis, both 30-day and 100-day MRD were associated with lower DFS rates (P=0.026 and P=0.006), but only day 30 MRD was significant in multivariate analysis (P=0.050). In the case of relapse, only MRD at day 100 was associated with increased risk in the univariate and multivariate analyses (HR 4.48, P=0.003 and HR 4.67, P=0.008). Chronic graft-versus-host-disease (cGVHD) was protective for NRM (HR 0.38, P=0.015). There was no difference in cumulative incidence of relapse (CIR) between transplant types (P=0.126). Forty-four (36.4%) patients died, with no difference between HCT type (P=0.307). Septic shock was the most frequent cause of death with 17 cases, with no difference between transplant typesConclusionsOutpatient peripheral blood allogenic HCT after RIC is a valid and effective alternative for adult patients suffering acute myeloblastic or lymphoblastic leukemia in low-income populations.

Abstract The Atacama Desert’s naturally elevated metal(loid)s pose a unique challenge for assessing the environmental impact of mining, particularly for indigenous communities residing in these areas. This study investigates how copper mining influences the dispersion of these elements in the wind‐transportable fraction (

Despite extensive research into the phylogenetic relationships of the genus Magnolia, Neotropical taxa have been neglected. This is partly because their numbers have recently doubled and now account for almost half of the global richness. Therefore, by sampling one-third of all Neotropical taxa their relationships were studied using morphological, nuclear, and plastome data. Two major clades were identified: Clade I, comprising Magnolia sect. Talauma, Magnolia sect. Splendentes from the Neotropics, and the Asian Magnolia sect. Gwillimia; while Clade II included the Neotropical clades Magnolia sect. Macrophylla and Magnolia sect. Magnolia, along with the remaining non-Neotropical sections. Within Clade I, Magnolia sect. Talauma was geographically divided into a northern subclade grouping Mexican and Central American taxa, and a southern subclade comprising South American and Caribbean taxa. Magnolia sect. Splendentes was also dichotomously divided, corresponding to the former Magnolia sect. Talauma subsect. Cubenses and Magnolia sect. Talauma subsect. Dugandiodendron. In Clade II, the relationships within Magnolia sect. Macrophylla and Magnolia sect. Magnolia were unclear, suggesting a species complex in all Magnolia sect. Macrophylla taxa. In total, 25 morphological traits were assessed, and ancestral state reconstructions were carried out. Only the joined clustering of mature follicles was a synapomorphy for the southern subclade of Magnolia sect. Talauma. In conclusion, this highlights the need to re-assess the taxonomic delimitation of certain groups, to update the infrageneric classification of Neotropical clades and to explore morphological traits to support them.

The oxygen minimum zone (OMZ) is an essential feature along the Pacific margin, extensively studied for its influence on benthic fauna, acquiring relevance in coastal zones due to its impact on aquaculture species, marine-managed areas, and marine-protected areas. The most evident temporal variability beyond seasonal timescales observed for the OMZ was related to inter-annual variability associated with El Niño, when warmer and more oxygenated waters arrive at shallower zones and the OMZ becomes deeper. However, the impact of oxygen-deficient water that appears sporadically over the shelf is not yet understood. This study provides an integrated view of the oceanographic and climatic conditions behind bottom oxygen conditions along the Chilean continental margin, considering the temporal variability in the South East (SE) Pacific during the last ~2000 years. We organized the information on redox-sensitive metals and δ15N from sedimentary cores obtained from shelf zones from 23°S to 36°S at water depths lower than 100 m. The results demonstrate the variability in the upper part of the OMZ over the shelf, which seems to respond to climatic oscillations. The element distribution indicated in particular a more intense OMZ was developed over the shelf before 1400 AD, followed by more oxygenated bottom conditions afterward, except between 1925 and 1970 off 36°S when the OMZ was intensified, a condition that was not observed at the northern sites. This period mostly coincided with a low Pacific Decadal Oscillation amplitude and reduced El Niño Southern Oscillation (ENSO) activity. In the last 50 years, the proxy data suggests less intense suboxic environment along the Chilean margin. This weakening of the upper boundary of the OMZ in the last decades is interpreted as resulting from the accumulative effect of ventilation processes at different time scales.

Taxonomic and functional microbial communities may respond differently to anthropogenic coastal impacts, but ecological quality monitoring assessments using environmental DNA and RNA (eDNA/eRNA) in response to pollution are poorly understood. In the present study, we investigated the utility of the co-occurrence network approach’s to comprehensively explore both structure and potential functions of benthic marine microbial communities and their responses to Cu and Fe fractioning from two sediment deposition coastal zones of northern Chile via 16S rRNA gene metabarcoding. The results revealed substantial differences in the microbial communities, with the predominance of two distinct module hubs based on study zone. This indicates that habitat influences microbial co-occurrence networks. Indeed, the discriminant analysis allowed us to identify keystone taxa with significant differences in eDNA and eRNA comparison between sampled zones, revealing that Beggiatoaceae, Carnobacteriaceae, and Nitrosococcaceae were the primary representatives from Off Loa, whereas Enterobacteriaceae, Corynebacteriaceae, Latescibacteraceae, and Clostridiaceae were the families responsible for the observed changes in Mejillones Bay. The quantitative evidence from the multivariate analyses supports that the benthic microbial assemblages’ features were linked to specific environments associated with Cu and Fe fractions, mainly in the Bay. Furthermore, the predicted functional microbial structure suggested that transporters and DNA repair allow the communities to respond to metals and endure the interacting variable environmental factors like dissolved oxygen, temperature, and salinity. Moreover, some active taxa recovered are associated with anthropogenic impact, potentially harboring antibiotic resistance and other threats in the coastal zone. Overall, the method of scoping eRNA in parallel with eDNA applied here has the capacity to significantly enhance the spatial and functional understanding of real-time microbial assemblages and, in turn, would have the potential to increase the acuity of biomonitoring programs key to responding to immediate management needs for the marine environment.

Arsenic is a highly toxic metalloid of major concern for public safety. However, microorganisms have several resistance mechanisms, particularly the expression of arsenic pumps is a critical component for bacterial ability to expel it and decrease intracellular toxicity. In this study, we aimed to characterize the biochemical, structural, and genomic characteristics of the Acr3 pump among a group of Exiguobacterium strains isolated from different sites of the arsenic-rich Salar de Huasco (SH) ecosystem. We also determined whether the differences in As(III) resistance levels presented by the strains could be attributed to changes in the sequence or structure of this protein. In this context, we found that based on acr3 sequences the strains isolated from the SH grouped together phylogenetically, even though clustering based on gene sequence identity did not reflect the strain’s geographical origin. Furthermore, we determined the genetic context of the acr3 sequences and found that there are two versions of the organization of acr3 gene clusters, that do not reflect the strain’s origin nor arsenic resistance level. We also contribute to the knowledge regarding structure of the Acr3 protein and its possible implications on the functionality of the pump, finding that although important and conserved components of this family of proteins are present, there are several changes in the amino acidic sequences that may affect the interactions among amino acids in the 3D model, which in fact are evidenced as changes in the structure and residues contacts. Finally, we demonstrated through heterologous expression that the Exiguobacterium Acr3 pump does indeed improve the organisms As resistance level, as evidenced in the complemented E. coli strains. The understanding of arsenic detoxification processes in prokaryotes has vast biotechnological potential and it can also provide a lot of information to understand the processes of evolutionary adaptation.

Indigenous communities from northern Chile have historically been exposed to the impacts of massive copper industrial activities conducted in the region. Some of the communities belonging to the Alto El Loa Indigenous Development Area are located less than 10 km from the “Talabre'' tailings dam, which contains residues from copper production and other metals that can be toxic to human health (e.g., As, Sb, Cd, Mo, Pb). Given the increasing demand of copper production to achieve net-zero emission scenarios and concomitant expansions of the tailings, the exposure to toxic metals is a latent risk to local communities. Despite the impact that copper production could generate on ancestral communities from northern Chile, studies and monitoring are limited and the results are often not made accessible for local communities. Here, we evaluate such risks by characterizing metal concentrations in dust collected from roofs and windows of houses from the Alto El Loa area. Our results showed that As, Sb, Cd, Cu, Mo, Ag, S, and Pb concentrations in these matrices can be connected to local copper mining activities. Additionally, air transport models indicate that high concentrations of toxic elements (As, Sb, and Cd) can be explained by the atmospheric transport of particles from the tailings in a NE direction up to 50 km away. Pollution indices and Health Risk Assessment suggested a highly contaminated region with a health risk for its inhabitants. Our analysis on a local scale seeks to make visible the case of northern Chile as a critical territory where actions should be taken to mitigate the effects of mining in the face of this new scenario of international demand for the raw materials necessary for the transition to a net-zero carbon global society.