Parasite biodiversity is underestimated or unknown in many regions, yet information on parasites is critical to understanding ecosystem structure and how this will change into the future. Understanding the diversity and role of parasites is especially important in regions exposed to anthropogenic pressures, such as aquatic ecosystems, as their interactions with other stressors can either exacerbate or mediate negative impacts. Water scarcity in the Brazilian semi-arid has led to a proliferation of reservoirs for human use. These artificial waterbodies host a diversity of taxa, including a large number of fish species; however, fish parasite diversity remains undocumented. This study investigated the parasitological diversity of fishes from reservoirs in the Paraíba and Mamanguape River basins in the Caatinga domain, Brazil – one of the most populated semi-arid regions worldwide. Eight reservoirs were studied, with fish sampled across the two phases of the hydrological cycle (dry and rainy seasons) using gillnets, cast nets, and trawl nets. Endo- and ecto-parasites were identified and enumerated, and parasitological indices (prevalence, intensity, and abundance) were calculated. In total, 1,170 individuals of 21 fish species were examined. Of these individuals, 42% were parasitized with at least one of 54 parasite taxa. We recorded 32 new geographical occurrences of parasites and 23 new fish-parasite interactions, expanding our understanding of ichthyoparasite diversity in the Brazilian semi-arid. Moving forward, it is important to develop knowledge around how anthropogenic changes (e.g., biological invasions, climate, and land use change) influence host-parasite structure and dynamics and ecosystem functioning in these ecosystems.

Objectives/Goals: pT217-tau is a novel fluid biomarker that predicts onset of Alzheimer’s disease (AD) symptoms, but little is known about how pT217-tau arises in brain, as soluble pT217-tau is dephosphorylated postmortem in the humans. Aging macaques naturally develop tau pathology with the same qualitative pattern and sequence as humans, including cortical pathology. Methods/Study Population: The etiology of pT217-tau in aging brains can be probed in rhesus macaques, where perfusion fixation allows capture of phosphorylated proteins in their native state. We utilized multi-label immunofluorescence and immunoperoxidase and immunogold immunoelectron microscopy to examine the subcellular localization of early-stage pT217-tau in entorhinal cortex (ERC) and dorsolateral prefrontal cortex (dlPFC) of aged rhesus macaques with naturally occurring tau pathology and assayed pT217-tau levels in blood plasma using an ultrasensitive nanoneedle approach. Results/Anticipated Results: pT217-tau labeling is primarily observed in postsynaptic compartments, accumulating in: 1) dendritic spines on the calcium-storing smooth endoplasmic reticulum spine apparatus near asymmetric glutamatergic-like synapses and 2) in dendritic shafts, where it aggregated on microtubules, often “trapping” endosomes associated with Aβ42. The dendrites expressing pT217-tau were associated with autophagic vacuoles and dysmorphic mitochondria, indicative of early neurite degeneration. We observed trans-synaptic pT217-tau trafficking between neurons within omega-shaped bodies and endosomes, specifically near excitatory, but not inhibitory synapses. We also examined pT217-tau in blood plasma in macaques across age-span and observed a statistically significant age-related increase in pT217-tau. Discussion/Significance of Impact: We provide direct evidence of pT217-tau trafficking between neurons near synapses to “seed” tau pathology in higher brain circuits, interfacing with the extracellular space to become accessible to CSF and blood. The expression of pT217-tau in dendrites with early signs of degeneration may help to explain why this tau species can herald future diseases.

Quorum sensing governs bacterial communication, playing a crucial role in regulating population behaviour. We propose a mathematical model that uncovers chaotic dynamics within quorum sensing networks, highlighting challenges to predictability. The model explores interactions between autoinducers and two bacterial subtypes, revealing oscillatory dynamics in both a constant autoinducer submodel and the full three-component model. In the latter case, we find that the complicated dynamics can be explained by the presence of homoclinic Shilnikov bifurcations. We employ a combination of normal-form analysis and numerical continuation methods to analyse the system.

Selenium is particularly necessary in infants because of their rapid physical growth period in addition to being indispensable for neurodevelopment. Severe deficiency can lead to cardiomyopathy, hypothyroidism and faltering growth. However, selenium can be toxic at high doses. In the pediatric age group, plasma/serum and erythrocyte selenium levels seem to increase with age, except in the first year of life. Understanding the variability in selenium status during this period can help to identify infants at risk of deficiency and develop strategies for controlling and preventing its consequences. This review aimed to identify the extent and characteristics of the variability of selenium status during the first year of life. A search was conducted across five databases to find articles published until July 30, 2024, with no limitations on the language or date of publication. Articles were screened, data were extracted independently by two reviewers, and any disagreement was resolved by a third reviewer. A total of 22 studies comprising 1288 participants were included in this review, 21 of which assessed plasma/serum selenium and 12 assessed erythrocyte selenium. In the first four months of age, serum/plasma selenium decreased, remained stable, or increased depending on feeding, with an increase in supplemented formula-fed infants and breastfed infants of supplemented mothers. Erythrocyte selenium levels showed a declining trend, except in infants fed supplemented formula or breastfed by supplemented mothers. Variability of serum/plasma and erythrocyte selenium levels in the first year was associated with maternal selenium intake/supplementation and the selenium content of the infant’s diet.

Auxinic herbicides are the second most-used herbicides in Brazil, and are often combined with glyphosate in pre-plant burndowns management. However, efficacy of these herbicides against Benghal dayflower at advanced growth stages remains poorly understood. Two field experiments were conducted in 2021 and 2022 on no-till fields naturally infested with Benghal dayflower at an advanced growth stage (approximately 50 cm height, 100% soil coverage) to evaluated the control efficacy of 2,4-D at 966 g ae ha−1, triclopyr at 720 g ae ha−1, fluroxypyr at 400 g ae ha−1, and dicamba at 720 g ae ha−1, alone or in combination with glyphosate (1,550 g ae ha−1). Dicamba was also tested at rates from 288 to 1,008 g ae ha−1. Results indicate that Benghal dayflower exhibits variable responses to auxin herbicides, and is influenced by both chemical family and the herbicide molecule. None of the treatments provided complete control at 8 wk after application (WAA). The highest visible control (∼77%) and dry mass reduction (∼57%) were provided by triclopyr (applied alone or combined with glyphosate) and 2,4-D (combined with glyphosate), followed by fluroxypyr (alone or combined with glyphosate) and 2,4-D (alone), providing approximately 69% visible control and 54% dry mass reduction. Even when statistical differences were detected by adding glyphosate to auxin herbicides, these differences were not sufficient to characterize a synergistic effect or improve control consistency. Dicamba (isolated or combined with glyphosate) provided the lowest control (∼54%) and dry mass reduction (∼30%). Additionally, dicamba doses up to 1,008 g ae ha−1 did not provide complete control (∼60% visible control and 51% dry mass reduction), suggesting that dicamba limitations cannot be mitigated through a dose increase. By highlighting the challenges in controlling Benghal dayflower at advanced growth stages, these results emphasize the importance of early-stage weed control and the need to carefully assess which auxin herbicides to use and when glyphosate mixtures are necessary.

The compromise effect arises when being close to the “middle” of a choice set makes an option more appealing. The compromise effect poses conceptual and practical problems for economic research: by influencing choices, it can bias researchers’ inferences about preference parameters. To study this bias, we conduct an experiment with 550 participants who made choices over lotteries from multiple price lists (MPLs). Following prior work, we manipulate the compromise effect to influence choices by varying the middle options of each MPL. We then estimate risk preferences using a discrete-choice model without a compromise effect embedded in the model. As anticipated, the resulting risk preference parameter estimates are not robust, changing as the compromise effect is manipulated. To disentangle risk preference parameters from the compromise effect and to measure the strength of the compromise effect, we augment our discrete-choice model with additional parameters that represent a rising penalty for expressing an indifference point further from the middle of the ordered MPL. Using this method, we estimate an economically significant magnitude for the compromise effect and generate robust estimates of risk preference parameters that are no longer sensitive to compromise-effect manipulations.

Drag reduction induced by a polydisperse solution of polyethylene oxide is investigated by direct numerical simulations of the Navier–Stokes equations coupled with the Lagrangian evolution of the polymers, modelled as dumbbells. Simulation parameters are chosen to match the experimental conditions of Berman (1977), who measured the polymer molecular weight distribution. Drag reduction is induced only by the few high molecular weight polymers fully stretched by the turbulent flow, whilst the hundreds of parts per million of low molecular weight chains are ineffective.

Quantum field theory predicts a nonlinear response of the vacuum to strong electromagnetic fields of macroscopic extent. This fundamental tenet has remained experimentally challenging and is yet to be tested in the laboratory. A particularly distinct signature of the resulting optical activity of the quantum vacuum is vacuum birefringence. This offers an excellent opportunity for a precision test of nonlinear quantum electrodynamics in an uncharted parameter regime. Recently, the operation of the high-intensity Relativistic Laser at the X-ray Free Electron Laser provided by the Helmholtz International Beamline for Extreme Fields has been inaugurated at the High Energy Density scientific instrument of the European X-ray Free Electron Laser. We make the case that this worldwide unique combination of an X-ray free-electron laser and an ultra-intense near-infrared laser together with recent advances in high-precision X-ray polarimetry, refinements of prospective discovery scenarios and progress in their accurate theoretical modelling have set the stage for performing an actual discovery experiment of quantum vacuum nonlinearity.

This study aimed to evaluate the effect of marine-based rumen buffer (Lithothamnium calcareum) supplementation on rumen health as well as milk yield and composition and also behavioural and metabolic parameters of dairy cows. Thirty-six lactating multiparous Holstein cows were used with a milk yield average of 39 kg/d and 64 d in milk. The experiment was conducted over 60 d using two groups: control (CON; n = 18) was supplemented with sodium bicarbonate at 1.1% dry matter and a treatment group that received Lithothamnium calcareum at 0.5% of dry matter (LITHO; n = 18). Each group was fed daily with the buffers mixed to the total mixed ration containing 29.28% starch. Ruminal fluid collections were performed weekly to evaluate pH and volatile fatty acids. Feeding behaviour data were obtained through automatic feeders, while overall behavioural data were obtained using monitoring collars. Milk yield was recorded daily and adjusted for fat and energy. Milk samples were retrieved once weekly for analysis of fat, protein, lactose and total solids. Blood samples were collected weekly for metabolic analysis and faecal samples were collected weekly to evaluate pH and starch concentrations. LITHO produced more fat- and energy-corrected milk (P ≤ 0.01) as well as the highest percentage of fat and solids (P < 0.05) when compared to the CON group. Data on feeding behaviour showed an increased eating time (P ≤ 0.01) in the LITHO group but a higher eating rate (P < 0.01) in the CON group. Animals from the LITHO group had lower faecal pH (P < 0.05). The treatment did not affect dry matter intake, animal behaviour, ruminal acid–base balance, or faecal starch. In summary, Lithothamnium calcareum supplementation at 0.5% of dry matter improved milk yield, milk composition and, presumably, feed conversion efficiency.

The Water-Enhanced Turbofan is a promising aero engine propulsion concept that could reduce the climate impact of aviation significantly by combining the conventional Joule/Brayton cycle with a Clausius-Rankine steam cycle. One important component with a high impact on the overall performance is the condenser, a heat exchanger cooling the core exhaust for water recovery. The design conditions for the Water-Enhanced Turbofan condenser have not been analysed from a system perspective in previous studies. Therefore, these operating conditions, which can be decisive for the dimensioning of the condenser, are investigated in the present work. These operating conditions include ambient temperature variations, different cruise altitudes, maximum cruise thrust and contrail avoidance. A conceptual design engine model is set up in the Numerical Propulsion System Simulation (NPSS) framework, incorporating a multi-point design scheme. The heat exchangers are modelled using a neural network surrogate model. The results show a trade-off between engine fuel burn and the cold size frontal area of the condenser, the latter being an indication for the integrability. It is shown that high ambient temperatures pose a challenge to the condenser design, necessitating consideration of such operating conditions in new engine concepts based on heat exchange with the environment. The condenser designed for typical cruise at 15K above standard atmosphere at 35,000 ft cruise altitude, enables sustained water cycle operations down to 10,000 ft under standard day conditions. Additionally, the complete cruise segment of the design mission can be flown with sustained water cycle operations at 10K above standard atmosphere conditions. A positive side effect of the condenser sizing for hot day conditions is that the probability of contrail formation is reduced because the condenser design results in excess water recovery at colder ambient conditions.

Basal bark application involves applying an oil-soluble herbicide in an oil carrier to the lower 0 to 45-cm of woody stems. For triclopyr, basal bark application typically requires the butoxyethyl ester formulation; however, this cannot be applied when standing water is present, which is common in seasonally flooded wetlands. Recently, the intermediate oil and water-soluble triclopyr acid formulation was registered for use in aquatic sites, allowing for basal bark applications in wetlands where standing water is present. Recent studies indicated that flooding after basal bark treatment can result in triclopyr release to surface waters and subsequent non-target injury. Elevated band application height (i.e., treating a higher band on each stem) may reduce non-target injury potential; however, this modified application technique has not been well tested on woody invasive species. To evaluate this approach, a field study on Schinus terebinthifolia was conducted near Melbourne and Wimauma, FL on well-established and juvenile rootstocks. Treatments included triclopyr acid at 17, 34, and 69 g L-1 applied in an oil carrier and treatment band heights of 0 to 45-cm and 61 to 107-cm from the ground line. At Melbourne, both band heights treated with 34 or 69 g L-1 resulted in 75 to 100% mortality of mature rootstocks. However, triclopyr applied at 17 g L-1 to the low and elevated band heights resulted in 70 and 11% mortality, respectively. All treatments resulted in 90 to 100% mortality at Wimauma, where the rootstocks were juvenile and much smaller. These findings indicate elevated band heights may be a useful approach for woody plant control and may support an effective management strategy in inundated wetlands that provides better prevention of non-target injury.

We present the first results from a new backend on the Australian Square Kilometre Array Pathfinder, the Commensal Realtime ASKAP Fast Transient COherent (CRACO) upgrade. CRACO records millisecond time resolution visibility data, and searches for dispersed fast transient signals including fast radio bursts (FRB), pulsars, and ultra-long period objects (ULPO). With the visibility data, CRACO can localise the transient events to arcsecond-level precision after the detection. Here, we describe the CRACO system and report the result from a sky survey carried out by CRACO at 110-ms resolution during its commissioning phase. During the survey, CRACO detected two FRBs (including one discovered solely with CRACO, FRB 20231027A), reported more precise localisations for four pulsars, discovered two new RRATs, and detected one known ULPO, GPM J1839 $-$10, through its sub-pulse structure. We present a sensitivity calibration of CRACO, finding that it achieves the expected sensitivity of 11.6 Jy ms to bursts of 110 ms duration or less. CRACO is currently running at a 13.8 ms time resolution and aims at a 1.7 ms time resolution before the end of 2024. The planned CRACO has an expected sensitivity of 1.5 Jy ms to bursts of 1.7 ms duration or less and can detect $10\times$ more FRBs than the current CRAFT incoherent sum system (i.e. 0.5 $-$2 localised FRBs per day), enabling us to better constrain the models for FRBs and use them as cosmological probes.