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.

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.

Here, we present a comprehensive morphological and molecular phylogenetic analysis of Clinostomum sp. (Digenea: Clinostomidae) metacercariae parasitizing two freshwater fish species from Southeast Brazil: Serrasalmus spilopleura (piranha) and Callichthys callichthys (tambuatá). The morphological examination revealed distinct characteristics of metacercariae in each host. Using the cytochrome c oxidase I (COI) gene barcode region, we obtained DNA sequences that allowed for accurate phylogenetic placement. Phylogenetic analyses revealed that Clinostomum sp. HM41 (metacercariae), isolated from S. spilopleura, exhibited 86% similarity to Ithyoclinostomum yamagutii, while Clinostomum sp. HM125 (metacercariae), from C. callichthys, showed 98.7% similarity to Clinostomum sp. Cr_Ha1. The phylogenetic trees constructed through Bayesian Inference and Maximum Likelihood methods indicated high biodiversity within the Clinostomum genus and strong support for distinct lineages. These findings enhance our understanding of the diversity and ecological distribution of Clinostomum species in South American freshwater 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.