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The savannah–forest mosaic of the Rupununi region of Guyana is a dispersal corridor between large tracts of intact Guiana Shield forests and a subsistence hunting ground for Indigenous Makushi and Wapichan communities. We conducted a camera-trap survey at 199 sites across four major forested habitat types and used multi-species occupancy modelling to determine regional-scale drivers of mammalian occupancy at both species and community levels, accounting for imperfect detection. We detected 47 savannah- and forest-dwelling mammal species, with the occupancy of medium- and large-bodied terrestrial mammal species (community occupancy) positively related to per cent forest cover and negatively to the presence of gallery forest habitat. The occupancy of 15 of 30 species was positively related to forest cover, suggesting the importance of maintaining forested habitat within the broader mosaic comprising savannahs and intermediate habitats for sustaining maximum mammal diversity. Jaguar Panthera onca occupancy was associated with the presence of livestock, and giant anteater Myrmecophaga tridactyla occupancy was negatively associated with distance to the nearest road, both results of concern in relation to potential human–wildlife conflict. The probability of detecting terrestrial mammal species (community detectability) increased away from villages, as did the detectability of two large-bodied, hunted species, the lowland tapir Tapirus terrestris and collared peccary Pecari tajacu, potentially indicating the negative effects of subsistence and commercial hunting in this savannah mosaic habitat. We use our findings to discuss how management strategies for hunting, fire, timber harvest and agriculture within Indigenous titled lands could help ensure the sustainability of these traditional livelihood activities.
Plasmodium simium, a parasite of platyrrhine monkeys, is known to cause human malaria outbreaks in Southeast Brazil. It has been hypothesized that, upon the introduction of Plasmodium vivax into the Americas at the time of the European colonization, the human parasite adapted to neotropical anophelines of the Kerteszia subgenus and to local monkeys, along the Atlantic coast of Brazil, to give rise to a sister species, P. simium. Here, to obtain new insights into the origins and adaptation of P. simium to new hosts, we analysed whole-genome sequence (WGS) data from 31 P. simium isolates together with a global sequence dataset of 1086 P. vivax isolates. Population genomic analyses revealed that P. simium comprises a discrete parasite lineage with greatest genetic similarity to P. vivax populations from Latin America – especially those from the Amazon Basin of Brazil – and to ancient European P. vivax isolates, consistent with Brazil as the most likely birthplace of the species. We show that P. simium displays half the amount of nucleotide diversity of P. vivax from Latin America, as expected from its recent origin. We identified pairs of sympatric P. simium isolates from monkeys and from humans as closely related as meiotic half-siblings, revealing ongoing zoonotic transmission of P. simium. Most critically, we show that P. simium currently causes most, and possibly all, malarial infections usually attributed to P. vivax along the Serra do Mar Mountain Range of Southeast Brazil.
The micronutrient chloride (Cl―) plays key roles in plant physiology, from photosystem II and vacuolar ATPase activity to osmoregulation, turgor maintenance and drought resilience, while also posing toxicity risks at high concentrations. This review examines Cl― uptake, transport and homeostasis, focussing on adaptations balancing its dual roles as a nutrient and toxicant. Key transporters, including NPF, SLAH, ALMT, CLC and CCC families, mediate Cl― fluxes to maintain ionic balance and prevent toxicity. Plants employ strategies such as selective uptake and vacuolar compartmentalization to cope with high salinity. Cl― also influences nitrogen-use efficiency and plant productivity. Advances in transporter biology reveal the role of Cl― in water-use efficiency, drought resilience and stress adaptation.
The stars of the Milky Way carry the chemical history of our Galaxy in their atmospheres as they journey through its vast expanse. Like barcodes, we can extract the chemical fingerprints of stars from high-resolution spectroscopy. The fourth data release (DR4) of the Galactic Archaeology with HERMES (GALAH) Survey, based on a decade of observations, provides the chemical abundances of up to 32 elements for 917 588 stars that also have exquisite astrometric data from the Gaia satellite. For the first time, these elements include life-essential nitrogen to complement carbon, and oxygen as well as more measurements of rare-earth elements critical to modern-life electronics, offering unparalleled insights into the chemical composition of the Milky Way. For this release, we use neural networks to simultaneously fit stellar parameters and abundances across the whole wavelength range, leveraging synthetic grids computed with Spectroscopy Made Easy. These grids account for atomic line formation in non-local thermodynamic equilibrium for 14 elements. In a two-iteration process, we first fit stellar labels to all 1 085 520 spectra, then co-add repeated observations and refine these labels using astrometric data from Gaia and 2MASS photometry, improving the accuracy and precision of stellar parameters and abundances. Our validation thoroughly assesses the reliability of spectroscopic measurements and highlights key caveats. GALAH DR4 represents yet another milestone in Galactic archaeology, combining detailed chemical compositions from multiple nucleosynthetic channels with kinematic information and age estimates. The resulting dataset, covering nearly a million stars, opens new avenues for understanding not only the chemical and dynamical history of the Milky Way but also the broader questions of the origin of elements and the evolution of planets, stars, and galaxies.
Aerosol-cloud interactions contribute significant uncertainty to modern climate model predictions. Analysis of complex observed aerosol-cloud parameter relationships is a crucial piece of reducing this uncertainty. Here, we apply two machine learning methods to explore variability in in-situ observations from the NASA ACTIVATE mission. These observations consist of flights over the Western North Atlantic Ocean, providing a large repository of data including aerosol, meteorological, and microphysical conditions in and out of clouds. We investigate this dataset using principal component analysis (PCA), a linear dimensionality reduction technique, and an autoencoder, a deep learning non-linear dimensionality reduction technique. We find that we can reduce the dimensionality of the parameter space by more than a factor of 2 and verify that the deep learning method outperforms a PCA baseline by two orders of magnitude. Analysis in the low dimensional space of both these techniques reveals two consistent physically interpretable regimes—a low pollution regime and an in-cloud regime. Through this work, we show that unsupervised machine learning techniques can learn useful information from in-situ atmospheric observations and provide interpretable results of low-dimensional variability.
Today, the range of the genus Euthria encompasses the Mediterranean and the eastern Atlantic, the region around southern Africa, and extends into the western Indo-Pacific. The genus, which has a geological history dating back to the Eocene of Europe, has recently undergone taxonomic revision in several European Neogene basins. These studies revealed a pronounced expansion during the Oligocene and Neogene in the Atlanto-Mediterranean region and the Paratethys, and these studies highlighted the overall diversity of the genus combined with a pronounced regional endemism. This paper reviews the fossil record of the genus in the western Iberian Pliocene of the Cainozoic Mondego Basin of Portugal. Two new species endemic to western Iberia with protoconchs showing non-planktotrophic developmental traits have emerged: Euthria galopimi n. sp. and Euthria lockleyi n. sp. These results reinforce the glocal character of Euthria, a genus that is both widespread and diversified, but simultaneously showing a high endemism. The contribution of nonplanktotrophic development to this scenario is discussed. Although well represented in the fossil record of Atlantic France, in present-day European waters, Euthria is represented by a single species, E. cornea (Linnaeus, 1758), and only in the Mediterranean and the northern shores of the Gulf of Cadiz. As with other warm-water molluscan taxa, the northern distribution limit of Euthria in the Atlantic has shifted southward since the Early to mid-Pliocene due to global cooling events and decreasing sea surface temperatures.
The description and delineation of trematode species is a major ongoing task. Across the field there has been, and currently still is, great variation in the standard of this work and in the sophistication of the proposal of taxonomic hypotheses. Although most species are relatively unambiguously distinct from their congeners, many are either morphologically very similar, including the major and rapidly growing component of cryptic species, or are highly variable morphologically despite little to no molecular variation for standard DNA markers. Here we review challenges in species delineation in the context provided to us by the historical literature, and the use of morphological, geographical, host, and molecular data. We observe that there are potential challenges associated with all these information sources. As a result, we encourage careful proposal of taxonomic hypotheses with consideration for underlying species concepts and frank acknowledgement of weaknesses or conflict in the data. It seems clear that there is no single source of data that provides a wholly reliable answer to our taxonomic challenges but that nuanced consideration of information from multiple sources (the ‘integrated approach’) provides the best possibility of developing hypotheses that will stand the test of time.
Whole-body and regional raw bioelectrical impedance analysis (BIA) parameters have been used to develop lean soft tissue estimation prediction models. Still, no regional fat mass (FM) assessment models have been provided. Hence, we aimed to develop and validate BIA-derived equations to predict regional FM against dual-energy X-ray absorptiometry (DXA) in healthy adults. One hundred and forty-eight adults (77 females) were included in this cross-sectional investigation. DXA assessed whole-body and regional FM and raw bioelectrical parameters of distinct body regions were measured using a 50 kHz phase-sensitive BIA analyser. BIA-derived equations were developed for each sex using a stepwise multiple linear regression approach in 2/3 of the sample and cross-validated in the remaining sample. The BIA-derived equations exhibited moderate to very strong relationships (P < 0·001) with DXA-measured FM of all body regions in females (r = 0·650 to 0·907) and males (r = 0·401 to 0·807). Also, for all the models, no significant deviation from linearity was found (P > 0·10). Agreement analyses revealed no associations between the differences and the means of the predicted and DXA-derived FM. However, the limits of agreement were large, with individual errors exceeding 50 % in females and 70 % in males. While the new BIA-derived equations provide a valid estimate of regional FM in middle-aged healthy adults at the population level, demonstrating a cost-effective alternative to DXA for assessing regional FM, caution is advised when applying these equations for individual-level analysis.
Epidemiological evidence shows a concerning rise in youth mental health difficulties over the past three decades. Most evidence, however, comes from countries in Europe or North America, with far less known about changes in other global regions. This study aimed to compare adolescent mental health across two population-based cohorts in the UK, and two population-based cohorts in Pelotas, Brazil.
Methods
Four population-based cohorts with identical mental health measures were compared. In Brazil, these included the 1993 Pelotas Birth Cohort and the 2004 Pelotas Birth Cohort. In the UK, cohorts included the Avon Longitudinal Study of Parents and Children, and the Millennium Cohort Study. Mental health was measured in all cohorts using identical, parent-rated scores from the Strengths and Difficulties Questionnaire (SDQ). This was assessed in both countries over approximately the same time periods, when adolescents were aged 11 (2004 vs 2015 in Brazil, and 2003 vs 2012 in the UK), with follow-up analyses focused on outcomes in later adolescence.
Results
Mental health problems were higher in the UK for adolescents born in the early 2000s compared to those born in the early 1990s. In Pelotas, the opposite was found, whereby problems were lower for adolescents born in the early 2000s compared to those born in the early 1990s. Despite these promising reductions in mental health problems in Pelotas over time, SDQ scores remained higher in Pelotas compared to the UK.
Conclusions
Our study represents the first to compare two population-based cohorts in the UK, and two population-based cohorts in Pelotas, Brazil, to understand how mental health problems have changed over time across the two settings. Our findings provide the most up-to-date insight into population-level rates of youth mental health problems in Pelotas, and shed novel insight into how these have changed over the last two decades in comparison to the UK. In doing so, our study provides a tentative first step towards understanding youth mental health over time at a more global scale, and presents a valuable opportunity to examine putative contributors to differences across time.
Though Health Technology Assessment (HTA) has steadily grown over the past decades, less attention has been paid to the way HTA may prove more responsive to the broader economic, social, and environmental challenges that health systems are facing today. In view of climate change, chronic diseases, an aging population, inequalities, and workforce issues, the HTA community’s unique set of skills nonetheless holds great potential to help decision-makers strengthen many publicly funded health systems around the world.
Methods
This article adopts an integrated system-wide perspective guided by the Responsible Innovation in Health (RIH) framework to explore how the HTA community may not only adapt to the speed of innovation but also consider its direction.
Results
Because RIH aims to steer innovation toward a more sustainable pathway, it can help HTA agencies anticipate decision-makers’ informational needs regarding four systemic challenges: (1) equitable access; (2) workforce issues; (3) accountable policy trade-offs; and (4) environmental sustainability. We clarify how key elements of the RIH framework may be used by HTA agencies to: (1) supplement their evaluation process; (2) align their priority-setting or strategic planning activities with their health system challenges; or (3) inform the production of early HTAs, horizon scans, or reports that are broader in scope than a single technology review.
Conclusions
The article concludes with three practical implications that were identified by the Institut National d’Excellence en Santé et Services Sociaux (INESSS) (Québec, Canada) and may inspire other HTA agencies.
Metal pollution is a major global issue in aquatic environments, affecting environmental quality and potentially altering host–parasite dynamics. This study evaluates the buffering role of a larval trematode Himasthla sp. under experimental conditions to test the effect of copper (Cu) exposure on the survival of the marine snail Echinolittorina peruviana. Snails were collected from intertidal rocky pools over a two-month period from Coloso (23°45’S, 70°28’W), northern Chile, and identified as parasitized or unparasitized. Both groups were then exposed to Cu concentrations (3 and 6 mg/L). Kaplan–Meier curves were used to determine the percentage of survival over time and the respective confidence intervals (CI). A nested ANOVA was conducted to assess whether rediae abundance per snail varied by experiment time, snail status, and Cu concentration. Snail survival was affected by both Cu-concentrations, but the effect was greater at 6 mg/L. At 3 mg/L, 57% (CI: 49.9–66.6%) of unparasitized snails were alive at 192 h, while 56% (CI: 46.6–67.4%) of parasitized snails survived at 216 h. At 6 mg/L, 42% (CI:35-51%) of unparasitized snails survived at 192 h, while 48% of parasitized snails survived at 216 h (CI:39-59%). Regardless of Cu concentration, after 240 h, all unparasitized snails had died, while 15% of parasitized snails remained alive. Dead snails harboured 125±53 rediae, while survivors had 194±73 rediae, with no significant differences between treatments. Our results show that parasitized snails survived longer than unparasitized snails, suggesting a trade-off between parasitism and host survival in polluted environments.
This study evaluated the effects of capsaicin (CAP) supplementation on the intake, nutrient digestibility, ruminal fermentation, nitrogen balance, microbial protein synthesis and health traits of bulls managed on pasture. Eight crossbred (Holstein x Zebu) cattle averaging 313 ± 31 kg of body weight (BW) were arranged in a replicated 4 × 4 Latin square design (one square of four bulls, rumen fistulated with 4-inch silicone cannulas and one square of four non-fistulated bulls), which were kept on Pangola grass pasture (Digitaria decumbens). Each experimental period consisted of 21 days, with 7 days for data collection (no washout between periods). Bulls were randomly assigned to the following treatments: CON (control): concentrate supplementation at 0.5% live weight (BW) and no additive (CAPCIN®), or concentrate supplementation at 0.5% BW in association with CAPCIN® (NutriQuest, Campinas, Brazil) fed at the inclusion rates of 150 (CAP150), 300 (CAP300) and 450 (CAP450) mg/animal/day. Digestibilities of dry matter, organic matter and neutral detergent fibre showed quadratic responses to CAP supplementation. Rumen pH linearly increased with CAP supplementation. The numbers of lymphocytes and eosinophils were linearly increased with CAP supplementation. The use of encapsulated pepper in supplements of crossbred (Holstein x Zebu) bulls managed on D. decumbens pasture up to 450 mg/animal/day improves nutrients digestibility and ruminal fermentation and can positively influence the health status of beef cattle managed under tropical conditions.
Clastic sedimentary systems and their characteristics are assumed not to have been modified by carbonate bioclastic grains until the Phanerozoic. Here, we show that the presence of carbonate bioclasts produced by disintegrated biomineralizing metazoans modified fine-grained siliciclastic facies in the Late Ediacaran Tamengo Formation, Brazil, ca. 555–542 Ma. The analysis of both polished sections and thin sections shows that sand-sized carbonate bioclasts (< 2 mm) derived from the Ediacaran metazoan Corumbella created diverse sedimentary features later found in the Phanerozoic record, such as bioclastic-rich horizontal and low-angle cross-laminations, erosive pods and lenses, bioclastic syneresis cracks, ripples preserved by bioclastic caps, microbial lamination eroded and filled with bioclasts, and entrapped bioclasts within microbial mats. These sedimentary features would have hardly been recorded in fine siliciclastic facies without the sand-sized bioclasts. Based on these features, together with other sedimentary evidence, Corumbella depositional settings in the Tamengo Fm. are reinterpreted as mid-ramp, subtidal settings. The multi-component organization of the skeleton of Corumbella favoured disarticulation to yield a sand-sized bioclast, so in turn creating a new complexity to shallow marine clastic settings typical of Phanerozoic marine depositional systems.
There is renewed interest in direct-drive inertial confinement fusion, following the milestone December 2022 3.15 MJ ignition result on the National Ignition Facility. A key obstacle is the control of the two-plasmon decay instability. Here, recent advances in inhomogeneous turbulence theory are applied to the broadband parametric instability problem for the first time. A novel dispersion relation is derived for the two-plasmon decay in a uniform plasma valid under broad-bandwidth laser fields with arbitrary power spectra. The effects of temporal incoherence on the instability are then studied. In the limit of large bandwidth, the well-known scaling relations for the growth rate are recovered, but it is shown that the result is more sensitive to the spectral shape of the laser pulse rather than to its coherence time. The range of wavenumbers of the excited plasma waves is shown to be substantially broadened, suggesting that the absolute instability is favoured in regions further away from the quarter critical density. The intermediate-bandwidth regime is explored numerically – the growth rate is reduced to half its monochromatic value for laser intensities of $10^{15} \ \text {W}\ \text {cm}^{-2}$ and relatively modest bandwidths of $5 \ \text {THz}$. The instability-quenching properties of a spectrum of discrete lines spread over some bandwidth have also been studied. The reduction in the growth rate is found to be somewhat lower compared with the continuous case but is still significant, despite the fact that, formally, the coherence time of such a laser pulse is infinite.
Evidence-based insertion and maintenance bundles are effective in reducing the incidence of central line-associated bloodstream infections (CLABSI) in intensive care unit (ICU) settings. We studied the adoption and compliance of CLABSI prevention bundle programs and CLABSI rates in ICUs in a large network of acute care hospitals across Canada.
Verrill's modern Mussismilia (the ‘brain corals’) were described in the 19th century, being hitherto considered endemic reef-building species to Brazil. Contrasting with the original diagnoses, highly variable morphological patterns have been observed among the congeners. Interspecific overlapping of major taxonomical characters has resulted in quite inconclusive use of the skeleton macromorphology for the genus. Intending to corroborate the Mussismilia taxonomy, a comparative morphological approach was developed, combining skeleton macro- and micromorphology. A total of 132 colonies was collected between 13°S and 17°S latitude (Mussismilia hispida = 53, Mussismilia harttii = 41, and Mussismilia braziliensis = 38). Qualitative (n = 9) and quantitative characters (n = 7) were selected (the latter was analysed with Kruskal–Wallis and a principal component analysis). A non-parametric test was adopted due to heteroscedasticity and the irregular sampling among populations. As a result, the corallite diameter and number of septa were significantly distinct among the species (α = 0.05). Micromorphology also differs interspecifically, being distribution and size of septal spines diagnostic for the congeners. Intraspecific variation and morphs are approached, ensuring the relevance of the skeleton for the interspecific delimitation and the species identities. Finally, field identification and/or methods based on image analyses from video transects should be adopted with caution. These practices may provide unreliable data, once the information is restricted to the view of the colony top, resulting in biased identification – majorly if the morphotypes of M. harttii and M. hispida share closely spaced corallites.
Visceral leishmaniasis (VL) is a tropical disease that can be fatal if acute and untreated. Diagnosis is difficult, the treatment is toxic and prophylactic vaccines do not exist. Leishmania parasites express hundreds of proteins and several of them are relevant for the host's immune system. In this context, in the present study, 10 specific T-cell epitopes from 5 parasite proteins, which were identified by antibodies in VL patients’ sera, were selected and used to construct a gene codifying the new chimeric protein called rCHI. The rCHI vaccine was developed and thoroughly evaluated for its potential effectiveness against Leishmania infantum infection. We used monophosphoryl lipid A (MPLA) and polymeric micelles (Mic) as adjuvant and/or delivery system. The results demonstrated that both rCHI/MPLA and rCHI/Mic significantly stimulate an antileishmanial Th1-type cellular response, with higher production of IFN-γ, TNF-α, IL-12 and nitrite in vaccinated animals, and this response was sustained after challenge. In addition, these mice significantly reduced the parasitism in internal organs and increased the production of IgG2a isotype antibodies. In vivo and in vitro toxicity showed that rCHI is safe for the mammalians, and the recombinant protein also induced in vitro lymphoproliferative response and production of Th1-type cytokines by human cells, which were collected from healthy subjects and treated VL patients. These data suggest rCHI plus MPLA or micelles could be considered as a vaccine candidate against VL.