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Abstract The subsurface oceans of Enceladus and Europa are thought to be some of the best candidate environments for finding life beyond Earth. Realistically, the first missions aimed at searching for life on these worlds will likely be restricted to the shallow subsurface. Here, we investigated whether indicators of life, or biosignatures, deposited near the surface could persist long enough to be detected, given that the extremely harsh conditions there would tend to degrade them. We exposed Bacillus subtilis spores to Ocean World surface conditions and used electron microscopy combined with spectroscopic approaches to assess the preservation potential of structural and morphological biosignatures derived from spores. Our results show that spore structure is highly resilient in the face of extreme conditions long after they have been inactivated, suggesting that methods targeting cell morphology would be valuable components in a suite of life detection strategies used in future missions to Ocean Worlds.

Abstract The aim of this study was to quantify the number of non-airborne bacteria that can passively penetrate the layers of four mask types (surgical mask, community face mask type 1 (CFM1), biocidal CFM1 and CFM2) and to determine the influence of wearing conditions for the surgical type. A mask wearer simulator consisting of a 3D anatomical replica of the upper airway connected to a breathing pump was used. Wearing time, filtration quality of the mask, fit (loose vs. tight) and breathing parameters (tidal volume, respiratory rate) were tested. A Staphylococcus epidermidis inoculum was applied to the inner layer. After the wearing simulation, the layers were separated and the bacteria counted. After four hours, no or only a few bacteria were present in the middle and outer layers. Most remained in the inner layer. Surgical mask and CFM1 retained more bacteria and provided a breeding ground for germs. The biocidal CFM1 rapidly reduced the number in the inner layer. The breathing parameters had no influence, in contrast to fit and wearing time. These results confirm that the standard test for bacterial filtration efficiency, which includes the active penetration of airborne bacteria into aerosol droplets, is the most objective measure of the ability of bacteria to penetrate through the mask layers, as the passive penetration ability of non-airborne bacteria is insignificant.

Biomass and carbon stocks of tropical African forests. A review. Introduction. Quantifying the biomass and carbon stocks contained in tropical forests has become an international priority for the implementation of the REDD+ mechanism. Forest biomass is estimated at three successive levels: the tree, the stand and the region level. This paper reviews the state of the art regarding the estimation of biomass and carbon stocks in tropical African forests. Literature. This review highlights the fact that very few allometric equations, equations used for estimating the biomass of the tree using non-destructive measurements (diameter, height), have been established for tropical African forests. At the stand level, the review highlights the spatial and temporal variations in biomass between forest types in Central and Eastern Africa. While biomass recovery after a disturbance (logging, for instance) is rather quick, a great deal of uncertainty still remains regarding the spatial variation in biomass, and there is no consensus on a regional biomass map. The quality of biomass mapping in tropical Africa strongly depends on the type of remotely-sensed data being used (optical, RADAR or LIDAR), and the allometric equation used to convert forest inventory data into biomass. Conclusions. Based on the lack of precision of the available allometric equations and forest inventory data and the large spatial scale involved, many uncertainties persist in relation to the estimation of the biomass and carbon stocks contained in African tropical forests.

Purpose: Entrepreneurship education (EE) through innovative teaching techniques (ITEE) and entrepreneurial intention (EI) are two essential components of entrepreneurship development. Using the assumptions of the Theory of Planned Behavior (TPB), we took three constructs: attitude (ATT), subjective norms (SUBNs), and perceived behavioral control (PBC), and from the assumption of Human Capital (HC) theory, we constructed another variable, ITEE. Thus, the fundamental objective of this study is to find out the essential predictor of EI between entrepreneurial antecedents (ATT, SUBNs, PBC) and ITEE through an artificial neural network (ANN). Design/methodology/approach: Using the snowball sampling technique, a highly structured questionnaire was sent to respondents. Finally, a sample size of 397 business graduate students was chosen. Findings: The findings revealed that two dimensions of entrepreneurial antecedents (attitude and subjective norm) positively impacted EI. Furthermore, ITEE partially mediated the relationship between two dimensions of entrepreneurial antecedents (attitude and subjective norm) and EI. Moreover, through ANN, we found that attitude (ATT) was a crucial predictor of EI among business graduate students in Bangladesh. Research limitations/implications: In this study, only business graduate students were included as respondents; thus, further research should include students from other departments or disciplines to generalize the findings. Practical implications: This study covers numerous actors in terms of practical contributions, including students, academics, the government, and the state. This article should draw the attention of Bangladesh government policymakers regarding the significance of ITEE for developing entrepreneurship. The research framework of this study proposed that ITEE should implement antecedents of entrepreneurship into business education, boosting the ability of students to make judgments, which will also enhance EI in the future. Originality/value: Integrating the TPB theory with human capital theory represents a significant scholarly advancement in business education for graduate students in Southeast Asia, namely Bangladesh. Furthermore, we developed a novel ITEE scale by synthesizing information from many literary sources, providing valuable insights for future researchers.

Ecology and management of the multipurpose Erythrophleum species (Fabaceae-Caesalpinioideae) in Africa. A review. Introduction. Widespread in Africa, the Erythrophleum genus includes four tropical tree species with a high economic and socio-cultural value: Erythrophleum ivorense, Erythrophleum suaveolens, Erythrophleum africanum and Erythrophleum lasianthum. Appropriate knowledge of the ecology and the distribution of these species is required for their sustainable management. This paper is based on an extensive literature review and summarizes the available information on the African Erythrophleum species in terms of botany, phylogeography, ecology, forestry and ethnobotany. Literature. Erythrophleum ivorense, E. suaveolens, E. africanum and E. lasianthum are morphologically different and occur in distinct climatic areas. They are non-pioneer light demander (E. ivorense and E. suaveolens) or pioneer species (E. africanum). Their primary mode of dispersal is via ballochore. The seeds have a dormancy period and can remain in the soil for several years. Their reproductive and foliar phenologies are regular and annual. Growth rate varies between species, ranging from 0.65 cm per year for E. ivorense to 0.16 cm per year for E. africanum. These trees are used in traditional medicine. Only E. ivorense and E. suaveolens (Tali) are mainly logged for timber. Conclusions. Erythrophleum species ecological data are better informed for E. ivorense and E. suaveolens because of their economic importance. This review highlights the existing lack of knowledge regarding the phenology (effects of climate, fructification periods), the minimum diameter of fructification and the mechanisms of natural seed dormancy breakage. Targeting such weaknesses is required to create or re-evaluate methods of conservation and/or enhancement of populations and logging practices.

Exploring the soil seed bank in order to gain a better understanding of the regeneration dynamic of African tropical forests. A review. The soil seed bank of the African moist forest has been very little studied in spite of the important role that it could play in natural sylvigenetic cycles. It could also be advantageously used in restoration programs, as has been seen on other continents. This review provides an update on the current knowledge regarding the soil seed bank, focusing, in particular, on the African continent. It reveals that a better characterization of the soil seed bank of different forest communities could constitute a significant contribution to the sustainable management of African tropical forests.

Abstract Engaging local communities is pivotal for wildlife conservation beyond protected areas, aligning with the 30 × 30 target of the Kunming-Montreal Global Biodiversity Framework. We assessed the effectiveness of 33 offtake indicators, derived from hunter declarations, in monitoring the status and extent of degradation of hunted wildlife sourced from camera trap surveys and faunal composition analysis. The rodents:ungulates ratio in offtake and the mean body mass of total offtake emerged as practical and robust indicators of faunal degradation within hunting systems, with significant potential for broader application in similar tropical forest environments. Our findings provide a blueprint for managing and conserving natural resources in tropical regions through community-based initiatives. Involving local stakeholders ensures sustainable wildlife use and fosters ownership and responsibility. This study advances conservation efforts, bridging scientific rigor with community engagement for effective biodiversity preservation.

Abstract A vast silvicultural experiment was set up in 1982 nearby the town of M’Baïki in the Central African Republic to monitor the recovery of tropical forests after disturbance. The M’Baïki experiment consists of ten 4-ha Permanent Sample Plots (PSPs) that were assigned to three silvicultural treatments in 1986 according to a random block design. In each plot, all trees with a girth at breast height greater than 30 cm were spatially located, numbered, measured, and determined botanically. Girth, mortality and newly recruited trees, were monitored almost annually over the 1982–2022 period with inventory campaigns for 35 years. The data were earlier used to fit growth and population models, to study the species composition dynamics, and the effect of silvicultural treatments on tree diversity and aboveground biomass. Here, we present new information on the forest stand structure dynamics and tree demography. The data released from this paper cover the three control plots and constitute a major contribution for further studies about the biodiversity of intact tropical forests.

Background: Long-read sequencing technology, widely used in research, is proving useful in clinical diagnosis, especially for infectious diseases. Despite recent advances, it hasn't been routinely applied to constitutional human diseases. Long-read sequencing detects intronic variants and phases variants, crucial for identifying recessive diseases. Methods: We integrated long-read sequencing into the clinical diagnostic workflow for the MEFV gene, responsible for familial Mediterranean fever (FMF), using a Nanopore-based workflow. This involved long-range PCR amplification, native barcoding kit library preparation, GridION sequencing, and in-house bioinformatics. We compared this new workflow against our validated method using 39 patient samples and 3 samples from an external quality assessment scheme to ensure compliance with ISO15189 standards. Results: Our evaluation demonstrated excellent performance, meeting ISO15189 requirements for reproducibility, repeatability, sensitivity, and specificity. Since October 2022, 150 patient samples were successfully analyzed with no failures. Among these samples, we identified 13 heterozygous carriers of likely pathogenic (LP) or pathogenic (P) variants, 1 patient with a homozygous LP/P variant in MEFV, and 4 patients with compound heterozygous variants. Conclusion: This study represents the first integration of long-read sequencing for FMF clinical diagnosis, achieving 100 % sensitivity and specificity. Our findings highlight its potential to identify pathogenic variants without parental segregation analysis, offering faster, cost-effective, and accurate clinical diagnosis. This successful implementation lays the groundwork for future applications in other constitutional human diseases, advancing precision medicine.

This study investigated the sanitary quality of digestates resulting from the mesophilic anaerobic digestion (AD) of urban and agricultural organic wastes (OWs). 40 sanitary indicators, including pathogenic bacteria, antimicrobial resistance genes, virulence factor genes, and mobile genetic elements were evaluated using real-time PCR and/or droplet digital PCR. 13 polycyclic aromatic hydrocarbons (PAHs) and 13 pharmaceutical products (PHPs) were also measured. We assessed agricultural OWs from three treatment plants to study the effect of different AD processes (feeding mode, number of stages, pH), and used three laboratory-scale reactors to study the effect of different feed-supplies (inputs). The lab-scale reactors included: Lab1 fed with 97% activated sludge (urban waste) and 3% cow manure; Lab2 fed with 85% sludge-manure mixture supplemented with 15% wheat straw (WS); and Lab3 fed with 81% sludge-manure mixture, 15% WS, and 4% zeolite powder. Activated sludge favored the survival of the food-borne pathogens Clostridium perfringens and Bacillus cereus, carrying the toxin-encoding genes cpe and ces, respectively. Globally, the reactors fed with fecal matter supplemented with straw (Lab2) or with straw and zeolite (Lab3) had a higher hygienization efficiency than the reactor fed uniquely with fecal matter (Lab1). Three pathogenic bacteria (Enterococcus faecalis, Enterococcus faecium, and Mycobacterium tuberculosis complex), a beta-lactam resistance gene (blaTEM), and three mobile genetic elements (intI1, intI2, and IS26) were significantly decreased in Lab2 and Lab3. Moreover, the concentrations of 11 PAHs and 11 PHPs were significantly lower in Lab2 and Lab3 samples than in Lab1 samples. The high concentrations of micropollutants, such as triclosan, found in Lab1, could explain the lower hygienization efficiency of this reactor. Furthermore, the batch-fed reactor had a more efficient hygienization effect than the semi-continuous reactors, with complete removal of the ybtA gene, which is involved in the production of the siderophore yersiniabactin, and significant reduction of intI2 and tetO. These data suggest that it is essential to control the level of chemical pollutants in raw OWs to optimize the sanitary quality of digestates, and that adding co-substrate, such as WS, may overcome the harmful effect of pollutants.

Key Clinical Message We present the case of a 54‐year‐old male with severe Parkinson's disease and chronic, non‐reversible pulmonary artery hypertension who had seizures and a cardiorespiratory arrest during surgery for deep brain stimulation, a minimally invasive procedure usually associated with a low risk of complications. This case illustrates how perioperative changes in antiparkinsonian therapy in patient with multiple comorbidities may significantly affect the risk profile.

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research-from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology-from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle.

Background: Gliomas, including the most severe form known as glioblastomas, are primary brain tumors arising from glial cells, with significant impact on adults, particularly men aged 45 to 70. Recent advancements in the WHO (World Health Organization) classification now correlate genetic markers with glioma phenotypes, enhancing diagnostic precision and therapeutic strategies. Aims and Methods: This scoping review aims to evaluate the current state of deep learning (DL) applications in the genetic characterization of adult gliomas, addressing the potential of these technologies for a reliable virtual biopsy. Results: We reviewed 17 studies, analyzing the evolution of DL algorithms from fully convolutional networks to more advanced architectures (ResNet and DenseNet). The methods involved various validation techniques, including k-fold cross-validation and external dataset validation. Conclusions: Our findings highlight significant variability in reported performance, largely due to small, homogeneous datasets and inconsistent validation methods. Despite promising results, particularly in predicting individual genetic traits, the lack of robust external validation limits the generalizability of these models. Future efforts should focus on developing larger, more diverse datasets and integrating multidisciplinary collaboration to enhance model reliability. This review underscores the potential of DL in advancing glioma characterization, paving the way for more precise, non-invasive diagnostic tools. The development of a robust algorithm capable of predicting the somatic genetics of gliomas or glioblastomas could accelerate the diagnostic process and inform therapeutic decisions more quickly, while maintaining the same level of accuracy as the traditional diagnostic pathway, which involves invasive tumor biopsies.

Objective: To determine if a lumbar musculature deficiency (paravertebral – PVM – and psoas – PM – muscles) is associated with a higher prevalence of vertebral fractures in osteoporotic patients. Methods: To constitute the fracture group, data were collected retrospectively from patients with one or more recent osteoporotic vertebral fractures between T10 and L5 such as non-injected computerized tomography (CT), dual-energy X-ray absorptiometry (DXA). A control group was made by matching the patients on age, bone mineral density measured by DXA and gender. We analyzed PM and PVM atrophy based on cross-sectional area (CSA) adjusted to the body area as well as fatty infiltration on a 3-level scale and the average muscle density in Hounsfield units (HU). Results: One hundred seventeen patients were included in each group. The fracture group had a lower PVM CSA than the control group (2197.92 ± 460.19 versus 2335.20 ± 394.42 mm2.m−2, respectively p = 0.015), but there was no significant difference in the PM (746.92 ± 197.89 versus 731.74 ± 215.53 mm2.m−2, respectively p = 0.575). The fracture group had a higher grade of fatty infiltration than the control group (PM: 1.3 ± 0.46 versus 1.07 ± 0.25, p < 0.001; PVM: 1.93 ± 0.5 versus 1.74 ± 0.5, p = 0.003) and a lower average muscle density (PM: 26.99 ± 12.83 versus 33.91 ± 8.12 HU, p < 0.001; PVM: 3.42 ± 21.06 versus 12.94 ± 18.88 HU, p < 0.001). Conclusion: This study shows an association between a lack of axial musculature and the occurrence of osteoporotic vertebral fractures. Preventive strengthening exercises could be proposed to osteoporotic patients.

IntroductionA substantial amount of research from the last two decades suggests that infants' attention to the eyes and mouth regions of talking faces could be a supporting mechanism by which they acquire their native(s) language(s). Importantly, attentional strategies seem to be sensitive to three types of constraints: the properties of the stimulus, the infants' attentional control skills (which improve with age and brain maturation) and their previous linguistic and non-linguistic knowledge. The goal of the present paper is to present a probabilistic model to simulate infants' visual attention control to talking faces as a function of their language learning environment (monolingual vs. bilingual), attention maturation (i.e., age) and their increasing knowledge concerning the task at stake (detecting and learning to anticipate information displayed in the eyes or the mouth region of the speaker).MethodsTo test the model, we first considered experimental eye-tracking data from monolingual and bilingual infants (aged between 12 and 18 months; in part already published) exploring a face speaking in their native language. In each of these conditions, we compared the proportion of total looking time on each of the two areas of interest (eyes vs. mouth of the speaker).ResultsIn line with previous studies, our experimental results show a strong bias for the mouth (over the eyes) region of the speaker, regardless of age. Furthermore, monolingual and bilingual infants appear to have different developmental trajectories, which is consistent with and extends previous results observed in the first year. Comparison of model simulations with experimental data shows that the model successfully captures patterns of visuo-attentional orientation through the three parameters that effectively modulate the simulated visuo-attentional behavior.DiscussionWe interpret parameter values, and find that they adequately reflect evolution of strength and speed of anticipatory learning; we further discuss their descriptive and explanatory power.

The contribution of dryland forests in West Africa to carbon stocks remains poorly documented due to the lack of appropriate allometric models and inventory data. In this study, we gathered such data for dryland forest relics of northern Côte d’Ivoire. Inventory data were used to determine and sample the dominant species, and to characterize the stand structure. Destructive biomass data were used to develop local mixed-species allometric models for estimating tree aboveground biomass (AGB) and test the validity of existing allometric models, and to characterize the stand structure (including carbon stock). A total of 118 tree species belonging to 102 genera and 36 families were inventoried in 41 plots of 25 × 25 m (625 m² each, totalling 2.56 ha) sampled in three sites in the Korhogo department. Among them, seven predominant species, including one exotic, were selected for destructive sampling in one site, the Lataha Forest Research Station. Destructive biomass data for 34 trees belonging to these dominant species and with diameter at breast height between 6 and 41 cm were used to fit allometric equations specific to this forest type and to test the predictions of existing equations earlier developed for the global tropics and for African dry forests. Six equations integrating three predictors, stem diameter (D), total tree height (H) and wood specific gravity (ρ) were developed and the models with the three predictors showed the best performance. Pantropical models significantly over-estimated tree AGB by 20 % while models developed for African dry forests provided reliable estimates, suggesting a specific allometry of trees in dryland forest relics that needs to be further explored.. With our best AGB model, a quantity of 141.26 ± 92.72 tDM.ha−1 was estimated confirming that these dryland forest relics are important carbon stocks for this region where open vegetation dominates. This study constitutes an important contribution for the carbon accounting programs related to the implementation of REDD+ initiatives in Côte d’Ivoire.