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Arsenic contamination of soils threatens the health of millions globally through accumulation in crops. While plants detoxify arsenic via phytochelatin (PC) complexation and efflux of arsenite from roots, arsenite efflux mechanisms are not fully understood. Here, white lupin (Lupinus albus) was grown in semi-hydroponics and exudation of glutathione (GSH) derivatives and PCs in response to arsenic was scrutinised using LC-MS/MS. Inhibiting synthesis of PC precursor GSH with L-buthionine sulfoximine (BSO) or ABC transporters with vanadate drastically reduced (>22%) GSH-derivative and PC2 exudation, but not PC3 exudation. This was accompanied by arsenic hypersensitivity in plants treated with BSO and moderate sensitivity with vanadate treatment. Investigating arsenic-phytochelatin (As-PC) complexation revealed two distinct As-PC complexes, As bound to GSH and PC2 (GS-As-PC2) and As bound to PC3 (As-PC3), in exudates of As-treated lupin. Vanadate inhibited As-PC exudation, while BSO inhibited both the synthesis and exudation of As-PC complexes. These results demonstrate a role of GSH-derivatives and PC exudation in lupin arsenic tolerance and reveal As-PC exudation as a new potential mechanism contributing to active arsenic efflux in plants. Overall, this study uncovers insight into rhizosphere arsenic detoxification with potential to help mitigate pollution and reduce arsenic accumulation in crops.

BackgroundThere is little robust data about the cardiovascular safety of hydroxychloroquine in patients with rheumatoid arthritis (RA), who often have cardiovascular comorbidities. We examined the association between use of hydroxychloroquine (HCQ) in patients with RA and major adverse cardiovascular events (MACE).MethodsIn a retrospective cohort of Medicare beneficiaries aged ≥ 65 years with RA, we identified patients who initiated HCQ (users) and who did not initiate HCQ (non-users) between January 2015-June 2017. Each HCQ user was matched to 2 non-users of HCQ using propensity score derived from patient baseline characteristics. The primary outcome was the occurrence of MACE, defined as acute admissions for stroke, myocardial infarction, or heart failure. Secondary outcomes included all-cause mortality and the composite of MACE and all-cause mortality. Cox proportional hazards model was used to compare outcomes between HCQ users to non-users.ResultsThe study included 2380 RA patients with incident HCQ use and matched 4633 HCQ non-users over the study period. The mean follow-up duration was 1.67 and 1.63 years in HCQ non-users and users, respectively. In multivariable models, use of HCQ was not associated with the risk of MACE (hazard ratio 1.1; 95% CI: 0.832-1.33). However, use of HCQ was associated with a lower risk of all-cause mortality (HR: 0.54; 95% CI: 0.45-0.64) and the composite of all-cause mortality and MACE (HR 0.67; 95% CI: 0.58-0.78).ConclusionHCQ use was independently associated with a lower risk of mortality in older adults with RA but not with incidence of MACE events. Key Points • Using an incident user design (to avoid the biases of a prevalent user design) and a population-based approach, we examined the effect of hydroxychloroquine (HCQ) on the risk of major cardiovascular events (MACE) in older patients with RA. • We did not find an association between HCQ use and incident MACE. We did, however, find a significant association with the composite outcome (MACE and all-cause mortality) driven by a significant reduction in all-cause mortality with HCQ use.

Abstract Aim The diagnosis of hypertrophic cardiomyopathy (HCM) with moderate hypertrophy is challenging. Hypertensive heart disease (HHD) is the most common differential diagnosis that mimics the LVH of HCM. The aim of this study was to compare the QRS duration in HCM and HHD to create a novel diagnostic tool to identify primary HCM. Methods and results We conducted an international retrospective multicentre study enrolling patients with true HCM and HHD. A total of 547 individuals with HCM and 139 with HHD were included. The median QRS duration was significantly shorter in HCM than in HHD (88 ms [80–94] vs. 98 ms [88–108]; P

Abstract Background Mycobacterium abscessus is an emerging pathogen causing severe pulmonary infections, particularly in individuals with underlying conditions, such as cystic fibrosis or chronic obstructive pulmonary disease. Macrolides, such as clarithromycin (CLR) or azithromycin (AZM), represent the cornerstone of antibiotherapy against the M. abscessus species. However, prolonged exposure to these macrolides can induce of Erm(41)-mediated resistance, limiting their spectrum of activity and leading to therapeutic failure. Therefore, inhibiting Erm(41) could thwart this resistance mechanism to maintain macrolide susceptibility, thus increasing the rate of treatment success. In our previous study, the Erm(41) methyltransferase was identified as a possible target enzyme of Cyclipostins and Cyclophostin compounds (CyC). Methods Herein, we exploited this feature to evaluate the in vitro activity of CLR and AZM in combination with different CyC via the checkerboard assay on macrolide-susceptible and induced macrolide-resistant M. abscessus strains selected in vitro following exposure CLR and AZM. Results Our results emphasize the use of the CyC to prevent/overcome Erm(41)‑induced resistance and to restore macrolide susceptibility. Conclusion This work should expand our therapeutic arsenal in the fight against a antibioticresistant mycobacterial species and could provide the opportunity to revisit the therapeutic regimen for combating M. abscessus pulmonary infections in patients, and particularly in erm(41)-positive strains.

Knowledge about the long history of the anthropogenic inputs of nitrogen (N) and phosphorus (P) is crucial to capture long-term N and P processes (legacies) and to investigate water quality and ecosystem health. These inputs include N and P point sources, which mainly originate from wastewater and which are directly discharged into surface waters, thus having an immediate impact on ecosystem functioning. However, N and P point sources are challenging to estimate, due to the scarcity of and uncertainty in observational data. Here, we contribute towards improved characterisation of N and P point sources from wastewater by providing a long-term (1950–2019), high-resolution (0.015625° ≈1.4 km on average) dataset for Germany. The dataset includes both domestic and industrial emissions treated in wastewater treatment plants and untreated domestic emissions that are collected in the sewer system. We adopt a modelling approach that relies on a large range of data collected from different sources. Importantly, we account for the uncertainties arising from different modelling choices (i.e. coefficients and downscaling approach). We provide 200 gridded N and P point source realisations, which are constrained and evaluated using available (recent) observations of wastewater treatment plants' outgoing loads. We discuss the uncertainties in our reconstructed dataset over a large sample of river basins in Germany and provide guidance for future uses. Overall, by capturing the long-term spatial and temporal variations in N and P point sources and accounting for uncertainties, our dataset can facilitate long-term and large-scale robust water quality studies. The dataset is available at https://doi.org/10.5281/zenodo.10500535 (Sarrazin et al., 2024).

Abstract Background The present study assessed physical activity (PA) and sedentary behavior (SB) levels and their motivational and emotional health-related correlates, in outpatients following a cardiovascular rehabilitation (CR) program, and compared these variables with those of a healthy control group. Methods The study included 119 participants: 68 CR outpatients (M age 57.76 ± 10.76; 86.76% males) and 51 control participants matched on age (M age 57.35 ± 6.33 years; 45.10% males). PA and SB were assessed using accelerometers during the first week post-discharge for outpatients and during a typical week for controls. Motivational (i.e., perceived capabilities, affective and instrumental attitudes, intention, approach-avoidance tendencies) and emotional health-related variables (i.e., anxiety, depressive symptoms, fatigue, pain intensity) were measured using validated scales. PA and SB data from 17 outpatients and 42 controls were valid for analysis, resulting in a final sample of 59 participants. Results CR outpatients engaged an average of 60.21 (± 34.79) min of moderate-to-vigorous PA (MVPA), and 548.69 (± 58.64) min of SB per day, with 18 more minutes of MVPA per day than controls (p = .038). Univariate and multivariate regressions indicated that positive affective attitudes were associated with higher MVPA (b = 10.32, R2 = 0.07, p = .029), and that males spent more time in SB than females (b = 40.54, R2 = 0.09, p = .045). Univariate and multivariate logistic regressions showed that meeting the World Health Organization’s weekly guidelines for MVPA was associated with higher perceived capabilities toward PA and more positive affective attitudes (OR = 1.17, p = .030; OR = 1.26, p

In the last decade, video games became a common vehicle for citizen science initiatives in life science, allowing participants to contribute to real scientific data analysis while learning about it. Since 2010, our scientific discovery game (SDG) Phylo enlists participants in comparative genomic data analysis. It is frequently used as a learning tool, but the activities were difficult to aggregate to build a coherent teaching activity. Here, we describe a strategy and series of recipes to facilitate the integration of SDGs in courses and implement this approach in Phylo. We developed new roles and functionalities enabling instructors to create assignments and monitor the progress of students. A story mode progressively introduces comparative genomics concepts, allowing users to learn and contribute to the analysis of real genomic sequences. Preliminary results from a user study suggest this framework may help to boost user motivation and clarify pedagogical objectives.

Abstract Over the past two decades, scientists have increasingly realized the importance of the three-dimensional (3D) genome organization in regulating cellular activity. Hi-C and related experiments yield 2D contact matrices that can be used to infer 3D models of chromosome structure. Visualizing and analyzing genomes in 3D space remains challenging. Here, we present ARGV, an augmented reality 3D Genome Viewer. ARGV contains more than 350 pre-computed and annotated genome structures inferred from Hi-C and imaging data. It offers interactive and collaborative visualization of genomes in 3D space, using standard mobile phones or tablets. A user study comparing ARGV to existing tools demonstrates its benefits.

Abstract Depression is associated with dysregulated circadian rhythms, but the role of intrinsic clocks in mood-controlling brain regions remains poorly understood. We found increased circadian negative loop and decreased positive clock regulators expression in the medial prefrontal cortex (mPFC) of a mouse model of depression, and a subsequent clock countermodulation by the rapid antidepressant ketamine. Selective Bmal1KO in CaMK2a excitatory neurons revealed that the functional mPFC clock is an essential factor for the development of a depression-like phenotype and ketamine effects. Per2 silencing in mPFC produced antidepressant-like effects, while REV-ERB agonism enhanced the depression-like phenotype and suppressed ketamine action. Pharmacological potentiation of clock positive modulator ROR elicited antidepressant-like effects, upregulating plasticity protein Homer1a, synaptic AMPA receptors expression and plasticity-related slow wave activity specifically in the mPFC. Our data demonstrate a critical role for mPFC molecular clock in regulating depression-like behavior and the therapeutic potential of clock pharmacological manipulations influencing glutamatergic-dependent plasticity.

Abstract Marine fisheries are increasingly impacted by climate change, affecting species distribution and productivity, and necessitating urgent adaptation efforts. Climate vulnerability assessments (CVA), integrating expert knowledge, are vital for identifying species that could thrive or suffer under changing environmental conditions. This study presents a first CVA for the Western Baltic Sea's fish community, a crucial fishing area for Denmark and Germany. Characterized by a unique mix of marine, brackish, and freshwater species, this coastal ecosystem faces significant changes due to the combined effects of overfishing, eutrophication and climate change. Our CVA involved a qualitative expert scoring of 22 fish species, assessing their sensitivity and exposure to climate change. Our study revealed a dichotomy in climate change vulnerability within the fish community of the Western Baltic Sea because traditional fishing targets cod and herring as well as other species with complex life histories are considered to face increased risks, whereas invasive or better adaptable species might thrive under changing conditions. Our findings hence demonstrate the complex interplay between life-history traits and climate change vulnerability in marine fish communities. Eventually, our study provides critical knowledge for the urgent development of tailored adaptation efforts addressing existing but especially future effects of climate change on fish and fisheries in the Western Baltic Sea, to navigate this endangered fisheries systems into a sustainable future.

Hematopoietic stem cells (HSCs) are a rare, long-lived and multipotent population that give rise to majority of blood cells and some tissue-resident immune cells. There is growing evidence that inflammatory stimuli can trigger persistent reprogramming in HSCs that enhances or inhibits the cellular functions of these HSCs and their progeny in response to subsequent infections. This newly discovered property makes HSCs a reservoir for innate immune memory. The molecular mechanisms underlying innate immune memory in HSCs are similar to those observed in innate immune cells, although their full elucidation is still pending. In this review, we examine the current state of knowledge on how an inflammatory response leads to reprogramming of HSCs. Understanding the full spectrum of consequences of reshaping early hematopoiesis is critical for assessing the potential benefits and risks under physiological and pathological conditions.

Rationale and Objective: Acute kidney injury (AKI) is a common complication among hospitalized adults, but AKI prediction and prevention among adults has proved challenging. We used machine learning to update the nephrotoxic injury negated by just-in time action (NINJA), a pediatric program that predicts nephrotoxic AKI, to improve accuracy among adults. Study Design: A retrospective cohort study. Setting and Population: Adults admitted for > 48 hours to the University of Iowa Hospital from 2017 to 2022. Exposure: A NINJA high-nephrotoxin exposure (≥3 nephrotoxins on 1 day or intravenous aminoglycoside or vancomycin for ≥3 days). Outcomes: AKI within 48 hours of high-nephrotoxin exposure. Analytical Approach: We collected 85 variables, including demographics, laboratory tests, vital signs, and medications. AKI was defined as a serum creatinine increase of ≥0.3 mg/dL. A gated recurrent unit (GRU)-based recurrent neural network (RNN) was trained on 85% of the data, and then tested on the remaining 15%. Model performance was evaluated with precision, recall, negative predictive value, and area under the curve. We used an artificial neural network to determine risk factor importance. Results: There were 14,480 patients, 18,180 admissions, and 37,300 high-nephrotoxin exposure events meeting inclusion criteria. In the testing cohort, 29% of exposures developed AKI within 48 hours. The RNN-GRU model predicted AKI with a precision of 0.60, reducing the number of false alerts from 2.5 to 0.7 per AKI case. Lowest hemoglobin, lowest blood pressure, and highest white blood cell count were the most important variables in the artificial neural network model. Acyclovir, piperacillin-tazobactam, calcineurin inhibitors, and angiotensin-converting enzyme inhibitor/angiotensin receptor blockers were the most important medications. Limitations: Clinical variables and medications were not exhaustive, drug levels or dosing were not incorporated, and Iowa’s racial makeup may limit generalizability. Conclusions: Our RNN-GRU model substantially reduced the number of false alerts for nephrotoxic AKI, which may facilitate NINJA translation to adult hospitals by providing more targeted intervention. Plain-Language Summary: Nephrotoxic acute kidney injury (AKI) is common and can potentially be prevented through preemptive adjustments of medications, as demonstrated by the success of the nephrotoxic injury negated by just-in time action (NINJA) program in pediatric populations. Translation of NINJA to the adult population has been challenging, and major barriers include high alert volume in adults that can lead to high resource utilization and alert fatigue. To address this issue, we developed a machine learning model for nephrotoxic AKI in adults that reduced the number of false alerts per AKI event from 2.5 to 0.7, which can enhance future NINJA implementation in adults by allowing for a more targeted intervention with fewer alerts and more efficient resource utilization.

This article introduces the GALDITE methodology, an adaptation of GALDIT used to assess seawater intrusion in coastal aquifers. GALDITE incorporates a new parameter (E) focusing on groundwater exploitation through artesian wells, previously overlooked in GALDIT. The methodology evaluates vulnerability using parameters like aquifer type, hydraulic conductivity, distance to coastline, and now groundwater extraction impact. Statistical validation using Barreiras aquifer data confirms the effectiveness of (E) in enhancing model accuracy. Sensitivity analysis highlights the parameter's significant influence on overall vulnerability assessment. The results indicate that the key impact zones identified include the downstream regions of the São Mateus, Doce, and Itabapoana rivers, as well as the municipality of Vitória, highlighting the applicability of GALDITE. The utility of GALDITE in managing coastal water resources, enhancing governance, and guiding sustainable strategies is emphasized, particularly in the face of increasing seawater intrusion risks exacerbated by intensive groundwater extraction. This study underscores the necessity of integrating groundwater exploitation into aquifer vulnerability assessments for effective coastal water management.

Abstract Background Identifying patient‐, facility‐, and environment‐level factors that influence the initiation and retention of comprehensive lifestyle management interventions (CLMI) for urban and rural Veterans could improve obesity treatment and reach at Veterans Affairs (VA) facilities. Aims This study identified factors at these various levels that predicted treatment engagement, retention, and weight management among urban and rural Veterans. Methods A retrospective cohort study of 631,325 Veterans was designed using VA databases to identify Veterans with class II and III obesity during 2015–2017. Primary outcomes were initiation of CLMI, bariatric surgery, or obesity pharmacotherapy within 1 year of index date. Secondary outcomes included treatment retention and successful weight loss. Generalized linear mixed models were used to evaluate the relationships between factors and obesity‐related outcomes, with rurality differences assessed through interaction terms. Results Patient characteristics associated with increased odds of initiating CLMI included female sex (p

Abstract X-ray Phase Contrast Tomography (XPCT) based on wavefield propagation has been established as a high resolution three-dimensional (3D) imaging modality, suitable to reconstruct the intricate structure of soft tissues, and the corresponding pathological alterations. However, for biomedical research, more is needed than 3D visualisation and rendering of the cytoarchitecture in a few selected cases. First, the throughput needs to be increased to cover a statistically relevant number of samples. Second, the cytoarchitecture has to be quantified in terms of morphometric parameters, independent of visual impression. Third, dimensionality reduction and classification are required for identification of effects and interpretation of results. To address these challenges, we here design and implement a novel integrated and high throughput XPCT imaging and analysis workflow for 3D histology, pathohistology and drug testing. Our approach uses semi-automated data acquisition, reconstruction and statistical quantification. We demonstrate its capability for the example of lung pathohistology in Covid-19. Using a small animal model, different Covid-19 drug candidates are administered after infection and tested in view of restoration of the physiological cytoarchitecture, specifically the alveolar morphology. To this end, we then use morphometric parameter determination followed by a dimensionality reduction and classification based on optimal transport. This approach allows efficient discrimination between physiological and pathological lung structure, thereby providing quantitative insights into the pathological progression and partial recovery due to drug treatment. Finally, we stress that the XPCT image chain implemented here only used synchrotron radiation for validation, while the data used for analysis was recorded with laboratory $$\mu$$ μ CT radiation, more easily accessible for pre-clinical research.

Abstract In this study, we explored spatial-temporal dependencies and their impact on the tactile perception of moving objects. Building on previous research linking visual perception and human movement, we examined if an imputed motion mechanism operates within the tactile modality. We focused on how biological coherence between space and time, characteristic of human movement, influences tactile perception. An experiment was designed wherein participants were stimulated on their right palm with tactile patterns, either ambiguous (incongruent conditions) or non-ambiguous (congruent conditions) relative to a biological motion law (two-thirds power law) and asked to report perceived shape and associated confidence. Our findings reveal that introducing ambiguous tactile patterns (1) significantly diminishes tactile discrimination performance, implying motor features of shape recognition in vision are also observed in the tactile modality, and (2) undermines participants’ response confidence, uncovering the accessibility degree of information determining the tactile percept’s conscious representation. Analysis based on the Hierarchical Drift Diffusion Model unveiled the sensitivity of the evidence accumulation process to the stimulus’s informational ambiguity and provides insight into tactile perception as predictive dynamics for reducing uncertainty. These discoveries deepen our understanding of tactile perception mechanisms and underscore the criticality of predictions in sensory information processing.

OBJECTIVES:. Anemia has been associated with an increased risk of both cardiac arrest and stroke, frequent complications of COVID-19. The effect of hemoglobin level at ICU admission on a composite outcome of cardiac arrest or stroke in an international cohort of COVID-19 patients was investigated. DESIGN:. Retrospective analysis of prospectively collected database. SETTING:. A registry of COVID-19 patients admitted to ICUs at over 370 international sites was reviewed for patients diagnosed with cardiac arrest or stroke up to 30 days after ICU admission. Anemia was defined as: normal (hemoglobin ≥ 12.0 g/dL for women, ≥ 13.5 g/dL for men), mild (hemoglobin 10.0–11.9 g/dL for women, 10.0–13.4 g/dL for men), moderate (hemoglobin ≥ 8.0 and < 10.0 g/dL for women and men), and severe (hemoglobin < 8.0 g/dL for women and men). PATIENTS:. Patients older than 18 years with acute COVID-19 infection in the ICU. INTERVENTIONS:. None. MEASUREMENTS AND MAIN RESULTS:. Of 6926 patients (median age = 59 yr, male = 65%), 760 patients (11.0%) experienced stroke (2.0%) and/or cardiac arrest (9.4%). Cardiac arrest or stroke was more common in patients with low hemoglobin, occurring in 12.8% of patients with normal hemoglobin, 13.3% of patients with mild anemia, and 16.7% of patients with moderate/severe anemia. Time to stroke or cardiac arrest by anemia status was analyzed using Cox proportional hazards regression with death as a competing risk. Covariates selected through clinical knowledge were age, sex, comorbidities (diabetes, hypertension, obesity, and cardiac or neurologic conditions), pandemic era, country income, mechanical ventilation, and extracorporeal membrane oxygenation. Moderate/severe anemia was associated with a higher risk of cardiac arrest or stroke (hazard ratio, 1.32; 95% CI, 1.05–1.67). CONCLUSIONS:. In an international registry of ICU patients with COVID-19, moderate/severe anemia was associated with increased hazard of cardiac arrest or stroke.

Abstract Restoring ecological dynamics is a key objective of conservation translocations. Exemplarily, reconnecting the reintroduced alpine populations with native Pyrenean populations through re‐establishing locally extinct populations in between, in the Causses and the Pre‐Alps, is a major goal for the long‐term conservation of Bearded Vultures in Europe. Understanding Bearded Vultures' post‐release movements and foraging behavior is critical to understanding the settlement of newly restored populations and to supporting conservation measures. The telemetric monitoring of 43 translocated and wild‐born juveniles allowed us to investigate whether differences exist in post‐release movements and foraging behavior during the first year of life between reintroduced and native populations. Medium‐ and long‐distance exploration movements start during the spring following fledging for both translocated and wild‐born individuals. However, birds translocated in the most distant release site (Causses) exhibited greater exploration distances with no clear directional movement pattern, had smaller home ranges, and had a stronger preference for supplementary feeding stations than those from other populations. Although some birds translocated in the Pre‐Alps displayed similar behaviors, the pattern is not as strong as in the Causses, likely because of the proximity to the breeding populations reintroduced in the Alps or differences in the number and management of supplementary feeding stations. Preference for supplementary feeding stations (SFS) mostly occurred in the Pre‐Alps and the native populations, but was lower in the Causses. Seasonal variations in SFS preference were consistent among populations, with a peak in the first spring following fledging. Beyond documenting post‐release movements in Bearded Vultures, we suggest better accounting for the demographic consequences of behaviors to track conservation translocation effectiveness, at both local and regional scales.

Background and Aims: Data on the prevalence and characteristics of so-called rare HCV genotypes (GTs) in larger cohorts is limited. This study investigates the frequency of rare GT and resistance-associated substitutions and the efficacy of retreatment in a European cohort. Methods: A total of 129 patients with rare GT1-6 were included from the European resistance database. NS3, NS5A, and NS5B were sequenced and clinical parameters and retreatment efficacies were collected retrospectively. Results: Overall 1.5% (69/4,656) of direct-acting antiviral (DAA)-naive and 4.4% (60/1,376) of DAA-failure patients were infected with rare GT. Although rare GTs were almost equally distributed throughout GT1-6 in DAA-naive patients, we detected mainly rare GT4 (47%, 28/60 GT4; of these n = 17, subtype 4r) and GT3 (25%, 15/60 GT3, of these n = 8, subtype 3b) among DAA-failures. A total of 62% (37/60) of DAA failures had not responded to first-generation regimes and the majority was infected with rare GT4 (57%, 21/37). In contrast, among patients with failure to pangenotypic DAA regimens (38%, 23/60), infections with rare GT3 were overrepresented (57%, 13/23). Although NS5A RASs were uncommon in rare GT2, GT5a, and GT6, we observed combined RASs in rare GT1, GT3, and GT4 at positions 28, 30, 31, which can be considered as inherent. DAA failures with completed follow-up of retreatment, achieved a high SVR rate (94%, 45/48 modified intention-to-treat analysis; 92%, 45/49 intention-to-treat). Three patients with GT4f, 4r, or 3b, respectively, had virological treatment failure. Conclusions: In this European cohort, rare HCV GT were uncommon. Accumulation of specific rare GT in DAA-failure patients suggests reduced antiviral activities of DAA regimens. The limited global availability of pangenotypic regimens for first line therapy as well as multiple targeted regimens for retreatment could result in HCV elimination targets being delayed. Impact and implications: Data on the prevalence and characteristics of rare HCV genotypes (GT) in larger cohorts are still scarce. This study found low rates of rare HCV GTs among European HCV-infected patients. In direct-acting antiviral (DAA)-failure patients, rare GT3 subtypes accumulated after pangenotypic DAA treatment and rare GT4 after first generation DAA failure and viral resistance was detected at NS5A positions 28, 30, and 31. The limited global availability of pangenotypic DAA regimens for first line therapy as well as multiple targeted regimens for retreatment could result in HCV elimination targets being delayed.

As the vegetation in the Arctic changes, tundra ecosystems along the southern border of the Arctic are becoming greener and gradually giving way to boreal ecosystems. This change is affecting local populations, wildlife, energy exchange processes between environmental compartments, and the carbon cycle. To understand the progression and the implications of this change in vegetation, satellite measurements and surface models can be employed. However, in situ observational data are required to validate these measurements and models. This paper presents observational data from two nearby sites in the forest–tundra ecotone in the Tasiapik Valley near Umiujaq in Northern Quebec, Canada. One site is on a mixture of lichen and shrub tundra. The associated data set comprises 9 years of meteorological, soil and snow data as well as 3 years of eddy covariance data. The other site, 850 m away, features vegetation consisting mostly of tall shrubs and black spruce. For that location, 6 years of meteorological, soil and snow data are available. In addition to the data from the automated stations, profiles of snow density and specific surface area were collected during field campaigns. The data are available at https://doi.org/10.1594/PANGAEA.964743 (Domine et al., 2024).

As sea-ice cover is shrinking, polar bears (Ursus maritimus, Phipps, 1774) face decreased access to seals, their primary prey, resulting in a greater dependence on terrestrial food sources. Whether polar bears can benefit from these terrestrial food sources, however, depends on their ability to find and capture prey items without expending more energy than is acquired. Here, we report one of the northernmost observations of polar bear predation on adult birds. The bear used a dive-hunting technique, which consisted of submerging itself, approaching underwater, and catching flightless greater snow geese (Anser caerulescens caerulescens (Linnaeus, 1758)) from beneath the surface of a tundra pond. After evaluating energy expenditures during swimming and energy intakes from consuming geese, we estimated that this rarely documented dive-hunting technique could be energetically profitable for a certain range of pursuit durations. This observation highlights the behavioral plasticity that polar bears can deploy to punctually exploit land-based food sources.

Abstract The recently discovered deep-sea Capelinhos hydrothermal edifice, ~ 1.5 km of the main Lucky Strike (LS) vent field (northern Mid-Atlantic Ridge), contrasts with the other LS edifices in having poorly-altered end-member hydrothermal fluids with low pH and chlorine, and high metal concentrations. Capelinhos unique chemistry and location offer the opportunity to test the effects of local abiotic filters on faunal community structure while avoiding the often-correlated influence of dispersal limitation and depth. In this paper, we characterize for the first time the distribution patterns of the Capelinhos faunal communities, and analyze the benthic invertebrates (> 250 µm) inhabiting diffusive-flow areas and their trophic structures (δ13C, δ15N and δ34S). We hypothesized that faunal communities would differ from those of the nearest LS vent edifices, showing an impoverished species subset due to the potential toxicity of the chemical environment. Conversely, our results show that: (1) community distribution resembles that of other LS edifices, with assemblages visually dominated by shrimps (close to high-temperature focused-fluid areas) and mussels (at low-temperature diffuse flow areas); (2) most species from diffuse flow areas are well-known LS inhabitants, including the bed-forming and chemosymbiotic mussel Bathymodiolus azoricus and (3) communities are as diverse as those of the most diverse LS edifices. On the contrary, stable isotopes suggest different trophodynamics at Capelinhos. The high δ15N and, especially, δ13C and δ34S values suggest an important role of methane oxidation (i.e., methanotrophy), rather than the sulfide oxidation (i.e., thiotrophy) that predominates at most LS edifices. Our results indicate that Capelinhos shows unique environmental conditions, trophic structure and trophodynamics, yet similar fauna, compared to other LS edifices, which suggest a great environmental and trophic plasticity of the vent faunal communities at the LS.