Recent publications
The spatial variation of soil water isotopes (SWI)—representing the baseline for investigating root water uptake (RWU) depths with water stable isotope techniques—has rarely been investigated. Here, we use spatial SWI depth profile sampling in combination with unmanned aerial vehicle (UAV) based land surface temperature estimates and vegetation indices (VI) in order to improving process understanding of the relationships between the spatial variability of soil water content and soil water isotope patterns with canopy status, represented in the form of VI. We carried out a spatial sampling of 10 SWI depth profiles in a tropical dry forest. UAV data were collected and analyzed to obtain detailed characterization of soil temperature and canopy status. We then performed a statistical analysis between the VI and land surface temperatures with soil water content and SWI values at different spatial resolutions (3 cm–5 m). Best relationships were used for generating soil water isoscapes for the entire study area. Results suggest that soil water content and SWI values are strongly mediated by canopy parameters (VI). Various VI correlate strongly with soil water content and SWI values across all depths. SWI at the surface depend on land surface temperature (R² of 0.66 for δ¹⁸O and 0.64 for δ²H). Strongest overall correlations were found at a spatial resolution of 0.5 m. We speculate that this might be the ideal resolution for spatially characterizing SWI patterns and investigate RWU in tropical dry forest environments. Supporting spatial analyses of SWI with UAV‐based approaches might be a future avenue for improving the spatial representation and credibility of such studies.
Solid forms transformations and new crystal structures of an active pharmaceutical ingredient (API) can occur due to various manufacturing process conditions, especially if the drug substance is formulated as a hydrate. The conversion between hydrate and anhydrate forms caused by changes in temperature and humidity must be evaluated because of the risk of dehydration and phase transitions during the manufacturing process. Differences in physicochemical, mechanical, and rheological properties have been observed between solid forms of the same API that can cause manufacturing and product-related issues. Atorvastatin calcium trihydrate (ACT) is a synthetic lipid-lowering agent that was discovered during Lipitor® (its anhydrous form) Phase 3 clinical trials after passing Phase I and II. This case highlights the importance of routinely performing solid form screenings because of the probability of finding new solid forms during the development and scale-up process. Therefore, in this contribution, ACT tablet formulation was performed and evaluated starting from the compatibility of 1:1 proportions of drug and the excipients microcrystalline cellulose 101 (MCC 101), calcium carbonate, lactose monohydrate, croscarmellose sodium, hydroxypropyl cellulose, magnesium stearate, and polysorbate 80. Then, 40 mg ACT tablets were prepared on a small pilot scale, and manufacturing process assessment was conducted by sampling process stages selected as critically prone to solid forms formation or phase transition. Final product quality was evaluated regarding weight variation, hardness, disintegration, dissolution, and assay tests. Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) were applied to solid state evaluation. The starting raw material was confirmed to be ACT Form I. From the preformulation studies, PXRD, FT-IR and TGA analyses showed no interactions between ACT and excipients, while DSC results revealed a physical interaction with MCC 101, not considered an incompatibility. The effect of the tablet manufacturing process was achieved by amorphization, while some ACT long-range crystalline structure remained, as confirmed by PXRD, FT-IR and DSC. However, the tablets’ quality parameters were found to be within the acceptable range of both the pharmacopeia guidelines and manufacturer parameters regarding weight variation, hardness, disintegration, dissolution, and assay tests.
Ecotourism promises to reconcile wildlife conservation and human development if negative impacts of human visitation and associated infrastructure can be minimized. Animal behavior studies can be used to identify individual and population responses to anthropogenic impacts before other fitness consequences are documented. With input from professionals in animal behavior and ecotourism, we identified key questions needed to better understand the impact of ecotourism on wildlife. Activity budgets, foraging, movement, stress, habituation, and reproduction were themes that emerged from our survey. We highlight promising research on these themes and identify remaining behavioral research questions about conserving wildlife in the context of ecotourism. Although ecotourism activities often have detrimental effects on animal behavior, we highlight research needs that can inform management and ecotourist education to improve human behavior to be more compatible with sustainable use of nature.
The first successful resolution of phylogenetic relationships within main lineages in the diverse Neotropical orchid genus Lepanthes Sw. is presented here. Genome skimming produced ten newly sequenced chloroplast genomes, with additional plastome coding genes (17–86) retrieved from GenBank, alongside 26 amplified matK and rITS genes, enabling phylogenetic reconstruction. The Lepanthes plastomes (157,185 − 158,260 bp, 37.15% GC content) contained 136 annotated genes, including 86 protein-coding, 42 tRNA, and 8 rRNA genes. Six hypervariable regions, including parts of the ycf1 gene, were identified as potential DNA barcodes. Phylogenetic analyses revealed that Carl Luer’s subgeneric classifications are non-monophyletic, reflecting significant morphological homoplasy. PCA and correlation analyses confirmed widespread homoplasy in continuous morphological characters. Six major clades were identified, though backbone resolution remains unresolved at two nodes of the phylogeny, requiring the use of nuclear markers or expanded sampling. Subgenus Marsipanthes species are non-monophyletic and constitute an East Andean early divergent clade with species from subgenus Lepanthes, while some derived Biogeographic Choco Marsipanthes clades were recovered, forming a polytomy with species from subgenus Lepanthes. The genus likely originated in southern Ecuador or northern Peru, dispersing across the Andes into the broader Neotropics. Although only a subset of Lepanthes diversity was sampled, the study captures significant taxonomic, geographic, and morphological variation. It provides foundational insights into the genus’s evolution, along with tools and hypotheses that can be expanded upon in future research to further refine our understanding of its evolutionary history.
Increased human activities on sandy beaches have significantly impacted ecosystems. This study aims to determine whether beaches with higher tourism and human activities exhibit greater impact on various ecological indicators compared to less-visited beaches. Ecological monitoring was performed across three sandy beaches, where sand samples were collected during three visits. Sediment characteristics, macrofauna presence, crab burrows abundance, and solid waste were analyzed. Fourteen benthic macrofauna taxa, 1209 crab burrows, and 7645 intertidal organisms were recorded. Notably, 98.8 % of the solid waste consisted of plastic items. Differences in organic matter, carbonates, the number of crab burrows, and macrofauna were observed, indicating that increased tourism and human activity influence these ecological indicators. These findings represent an initial step toward more rapid and comprehensive ecological monitoring of beaches, contributing to coastal environmental management and decision-making.
Leucine is an essential branched-chain amino acid required for skeletal muscle protein synthesis as a substrate and as a key anabolic signaling molecule primarily via activation of the mTORC1. Leucine supplementation has been proposed to enhance muscle adaptations, with some studies showing improvements in muscle growth. However, results from randomized controlled trials (RCTs) have been inconclusive, potentially due to variations in resistance exercise protocols and Leu dose or duration of supplementation. This systematic review explores the effects of leucine supplementation on resistance-training-induced muscle growth, strength, and recovery in healthy individuals.
A systematic literature search was conducted across multiple databases (MedLine, EMBASE, PubMed, Science Direct, Scopus, and Cochrane) to identify RCTs investigating the effect of leucine intake on markers of muscle growth, strength, and recovery in trained adults aged 18 to 40 years old.
A total of 14 RCTs were identified including acute (n = 5) and chronic leucine (n = 9) supplementation. A total of 13 studies did not find significant differences in muscle mass, strength, or recovery between leucine-supplemented and placebo groups.
The evidence from this systematic review suggests that leucine supplementation does not confer significant benefits in muscle growth, strength, or recovery in healthy, trained young adults.
Many Drosophila species coexist by sharing their feeding and breeding sites, which may influence their oviposition choices in an interspecies social context. Whether and where to lay eggs is a crucial decision for female flies as it influences the success of their offspring, by minimizing the risk of predation, competition, or cannibalism. Significant gaps exist in our understanding of Drosophila oviposition dynamics in co-occurring species. Here we tested oviposition strategies of Drosophila melanogaster and its close relative Drosophila simulans under different conditions, to assess whether a single female would prefer to oviposit separately or together with another female, be it a conspecific or not. We find that ovipositing females, regardless whether they are conspecifics or not, prefer to oviposit at the same site. This might suggest that the flies regard the benefits of sharing oviposition sites as higher than the potential risks of competition or cannibalism. The willingness to share oviposition sites was lower when the nutritional value of the medium was increased by adding yeast, and was lost when flies were allowed to lay the eggs consecutively, instead of being tested together. The latter might be explained by our additional finding that females become attracted by the presence of other females on oviposition substrates and that this attraction is partly driven by visual cues. Ovipositing in groups might facilitate intra- and interspecific social feeding of same age offspring, as well as enrichment of microbes. However, this cooperation dynamic might change if another female’s offspring is already present, as it might be perceived as danger of competition or cannibalism.
Urban green spaces (UGS) provide essential ecosystem services (ES), for example, precipitation infiltration for flood mitigation, transpiration (Tr) for local atmosphere cooling and groundwater recharge (Gr) for drinking water provision. However, vegetation type impacts the ecohydrological partitioning of incoming precipitation and therefore ES provision, whilst flux rate potential is different in disparate hydroclimates. Consequently, paired studies in different hydroclimates are useful to understand similarities and differences in vegetation controlled ecohydrological partitioning to effectively guide UGS management. We simultaneously undertook sub‐daily soil moisture measurements beneath three contrasting urban vegetation types (grass, shrub, mature tree) between 01/01/2021 and 31/12/2023 for an inter‐comparison of an energy‐limited Scottish and a moisture‐limited region of Germany. These data were integrated with hydroclimatic and sapflux data in the EcoHydroPlot model to constrain estimates of ecohydrological fluxes. Soil moisture data showed clear effects of the contrasting hydroclimates, with high and low VWC values in Scotland and Germany, respectively, whilst evapotranspiration potential was ~50% greater in Germany. Consequently, ecohydrological functioning and flux rates were fundamentally different, with Tr dominant in Germany and Gr dominant in Scotland. However, vegetation cover was shown in both countries to be a key control on urban ecohydrological partitioning with grass encouraging Gr, contrasting to evergreen shrubs in Scotland and mature trees in Germany elevating Tr. In Germany, impacts to hydrological functioning due to low soil VWC were marked with the mature trees high Tr rate shutting down Gr for the majority of the study period. The German site also showed greater hydrological functioning susceptibility to inter‐annual hydroclimatic variability with all fluxes heavily suppressed during the 2022 drought. In contrast, the high VWC in Scotland provided some buffer against ongoing negative rainfall anomalies. Overall, the study indicated the importance of diverse UGS vegetation cover to encourage contrasting ecohydrological fluxes.
Background
Snakebite (SB) envenoming is an acute emergency requiring early care delivery. However, sometimes, patients can take several hours before receiving antivenom (AV). We conducted this study to assess the effectiveness of antivenom in the recovery of clotting parameters in patients consulting tardily after SB envenoming in French Guiana. The primary endpoint of our study was to investigate the time needed from SB to recovery from SB-induced coagulopathy. The secondary endpoint was to investigate the time needed from AV administration to recovery from SB-induced coagulopathy in patients receiving AV (late or very late administration).
Methods
This prospective observational study was conducted in the Intensive Care Unit (ICU) of Cayenne General Hospital between January 2016 and September 2023. We included all patients hospitalized for SB envenoming who either did not receive AV or received it more than 6 h after SB. We excluded patients who received antivenom in less than 6 h from the SB and those who received incomplete AV doses.
Findings
We included 58 patients in the No AV group, 51 in the late AV group (6 h ≤ AV < 12 h), and 50 in the very late AV group (AV≥12 h). The median age of patients was 42 years (IQR: 29–53), 65.4% were male and 34.6% were female (104 and 55 out of 159 patients) without difference regarding the demographic parameters between groups. Data regarding ethnicity was not available. The median time from SB to AV was 8.5 h (IQR: 6.9–10) in the late AV group and 21.1 h (IQR: 16.7–27.4) in the very late AV group (p < 0.001). The time from SB to normal clotting parameters was shorter in patients receiving late AV than in those receiving very late AV and those not receiving AV. No differences were observed in the time from SB and recovery of fibrinogen and activated partial thromboplastin time (aPTT) between very late AV and no AV. However, the International Normalized Ratio (INR) recovery was shorter in the very late AV group than in the no AV group. On the other hand, the time from AV to normal fibrinogen was shorter in patients receiving very late AV than in patients receiving late AV (Log-Rank = 0.020). Meanwhile, the time from AV to normal INR or normal aPTT was similar in patients receiving very late AV compared to patients receiving late AV (Log-Rank = 0.722 and 0.740, respectively).
Interpretation
Late AV administration effectively reverses coagulopathic manifestations after SB envenoming. However, very late AV administration did not improve the correction of some clotting parameters when compared to patients not receiving AV. Our findings could be explained by the combination of venom toxicokinetics and the kinetics of the synthesis of clotting factors.
Funding
No funding.
Background: Several studies have shown that tranexamic acid (TXA), an anti-fibrinolytic agent, may reduce hematoma expansion (HE) in intracerebral hemorrhage (ICH), but its therapeutic time window is unclear. We analyzed the efficacy and safety of TXA based on its time of administration after hemorrhage onset.
Methods: We searched PubMed, Embase and Cochrane databases for randomized controlled trials (RCTs) published up to July 27, 2024 comparing TXA with placebo in ICH. We excluded trials that used TXA for longer than 3 days which causes delayed vasospasm, increasing the risk of cerebral ischemia. The primary outcomes were HE, 24-hour hemorrhagic volume change, 90-day mortality and poor functional outcome. We grouped the trials into 2 hours, 8 hours or 24 hours of TXA administration after hemorrhage onset. We pooled odds ratios (OR) and mean differences (MD) with 95% confidence intervals (CI) using Rstudio. Heterogeneity was examined with the I2 test.
Results: We included 12 studies with 3,567 patients. Most of the studies used 1 g TXA in patients with Glasgow Coma Scale score ranging from 13-15. TXA reduced HE risk (OR 0.85; 95% CI 0.73 to 0.98; p= 0.03; I2= 0%). This reduction was observed in studies that administered TXA within 8 hours of ICH onset (OR 0.82; 95% CI 0.70 to 0.97; p= 0.02; I2= 0%). TXA slightly reduced 24-hour hemorrhagic volume (MD -1.30 mL; 95% CI -2.51; -0.09; p= 0.04; I2= 47%). This reduction was mainly seen in patients who were administered TXA within 8 hours of hemorrhage onset (MD -1.86 mL; 95% CI -3.15 to -0.58; p< 0.01; I2= 35%). There were no significant differences in poor functional outcome (OR 0.87; 95% CI 0.67 to 1.15; p= 0.34; I2= 24%), 90-day mortality (OR 1.00; 95% CI 0.84 to 1.19; p= 0.96; I2= 0%), major thromboembolic events (OR 1.22; 95% CI 0.82 to 1.82; p= 0.33; I2= 0%), neurosurgical intervention (OR 0.94; 95% CI 0.61-1.45; p= 0.78; I2= 0%) or length of hospital stay (MD -0.49 days; 95% CI -3.27 to 2.29; p= 0.73; I2= 0%).
Conclusion: TXA reduced the risk of HE and slightly reduced 24-hour hemorrhagic volume in patients with ICH within 8 hours. Larger RCTs stratifying administration timing are required to establish these findings.
Energy poverty remains a critical challenge in Central America, where significant disparities in access to modern energy services persist. These disparities are closely linked to income inequality and are more pronounced in rural areas than in urban centers. In 2014, Guatemala had the highest level of unequal access to electricity across all income levels, while Costa Rica had the best access. Despite improvements in countries such as Panama, Costa Rica, and El Salvador between 2016 and 2022, many households, particularly in economically disadvantaged regions, still rely on low-quality energy sources such as firewood and charcoal for cooking. Indigenous populations in Guatemala, Nicaragua, and Panama face severe ethnic segregation in access to electricity, although access among these communities is gradually increasing. This chapter explores the multifaceted issue of energy poverty in Central America, examining its social, economic, and geographic dimensions. It highlights key challenges, including limited electricity infrastructure, high energy costs, political instability, and climate vulnerability. It also discusses potential solutions and initiatives, such as the development of renewable energy, the implementation of energy efficiency measures, policy and regulatory reforms, and improved access to financing. It also reviews government efforts to promote an integrated energy policy agenda focused on renewable energy, energy transition and energy security. These challenges can be addressed through comprehensive and sustainable strategies, the region can work towards equitable access to modern energy services for all its inhabitants.
As scientists, change is the only constant in our journey. We often find ourselves in transition from one laboratory to another, and during our training we are fortunate to experience the excitement of pursuing postgraduate studies abroad in well‐funded, high‐level research centers. However, after completing doctoral or postdoctoral training, we are frequently drawn to return to our home countries, where funding and support for science are significantly more limited. In this brief commentary, first, I would like to highlight the challenges faced by scientists from developing countries who have had the opportunity to train internationally and then choose to return home, driven both by personal motivations (e.g., family) and by the desire to contribute to the scientific advancement of their regions. Second, I would like to share some advice that has been especially useful to me in establishing my laboratory, defining research topics, and maintaining academic productivity. I hope these insights can be useful to colleagues in similar situations across different regions. Although starting a research group in regions with less investment in Research and Development is challenging, it is achievable with perseverance and the implementation of concrete actions.
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