Investigating the drivers of maturation dynamics in Barents Sea haddock (Melanogrammus aeglefinus)

Changes in size and age at maturation of many exploited fish stocks have been investigated and the influences of environmental factors and exploitation have often been inferred, but not explicitly investigated. Here we determine probabilistic maturation reaction norms (PMRNs) for Barents Sea haddock (Melanogrammus aeglefinus) using generalized linear models (GLMs) and mixed effect models (GLMMs), which account for the correlation among samples within a tow station, and investigate the effects of fishing mortality, environmental factors (NAO, water temperature, and salinity), and potential density dependence or species interaction effects. We found little evidence of a consistent trend in maturation tendencies for Barents Sea haddock for cohorts 1983–2003, ages 4–6 years. Female haddock matured at larger lengths for a given age than males, but overall patterns were similar for both sexes. The GLMM approach gave consistently higher PMRN midpoint estimates than the GLM approach, which indicated that PMRNs that do not account for correlations within the data may bias estimates. Environmental factors, rather than exploitation, density dependence, or species interactions, were responsible for the observed changes in size and age at maturation in Barents Sea haddock during the late 1980s through early 2000s. Little evidence of fisheries-induced evolution was found in these fish over the time period investigated. The lack of a significant temporal trend in maturation may be due to several challenges in estimating representative population parameters for this stock, the trait change being in a period of stasis or reversal, or adaptation by the fish to higher exploitation in the past resulting in negligible evolutionary selection during the study period when exploitation has been more moderate

Temporal trends in a large marine ecosystem

Different scales of change imply the need for different approaches to study change in ecosystems. I determined if proximate causes for ecosystem change are apparent at different biological and spatial scales by analyzing time series at fairly short temporal scales (< 30 years). I determined whether complex dynamics involving abundance could be described for a single species whose population units are distinctly defined, for two deep-sea species, and for the demersal fish community of the northeast Newfoundland-Labrador Shelf using two newer approaches of multivariate time series analysis: minimax autocorrelation factor analysis (MAFA) and dynamic factor analysis (DFA). I analyzed trends in abundance and, for the demersal community, mean size and investigated the relationships between observed trends and external factors (environmental, exploitation and natural (non-human) predation) operating on time lags. No one factor fully explained fish population and community dynamics in the Northwest Atlantic, but rather a combination of factors operating over several temporal scales were largely responsible for the dynamics seen today. No one scale captures all the dynamics in abundance and mean size for populations, deep-sea species, or the fish community. -- Before using the techniques on deep-sea species, I wanted to determine if the data were adequate to describe trends in "non-traditional" fishery species; for this, I used generalized linear models. I discovered several deep-sea species qualified as endangered. From that analysis arose questions regarding statistical rigor: does the loss of comprehensiveness bias results? I assessed several approaches to analyzing population change that explicitly dealt with differing degrees of data filtering and the comprehensiveness of associated metrics with a detailed examination of two North Atlantic endemic deep-sea species, Macrourus berglax and Coryphaenoides rupestris. Statistical rigor is necessary, not to show that a trend exists in available data for deep-sea species, but to ensure that the trend is real. When assessing temporal trends under any conditions, ensuring the comparability of the index over time is extremely important

Oxo-aglaiastatin-mediated inhibition of translation initiation

We thank Dr. Elias George (McGill University) for the kind gift of Pgp-1-expressing HeLa cells. RIM was supported by a doctoral fellowship from the Cole Foundation. This research was supported by a grant from the Canadian Institutes of Health Research (FDN-148366) to JP. J.A.P., Jr. is supported by NIH Grant R35 GM118173. Work at the Boston University Center for Molecular Discovery is supported by Grant R24 GM111625. (Cole Foundation; FDN-148366 - Canadian Institutes of Health Research; R35 GM118173 - NIH; R24 GM111625)Published versionSupporting documentatio

“Do you Know What's Underneath your Feet?”: Underground Landscapes & Place‐Based Risk Perceptions of Proposed Shale Gas Sites in Rural British Communities

Resource extraction relies on human interaction with the underground, often near rural communities. Yet, little research has explored localized, place-based relationships to the underground and subsequent concerns tied to proposed energy activities. This paper highlights the importance of place in localized risk perceptions of proposed shale exploration in two rural communities in the United Kingdom. Through qualitative case studies we examine how senses of place and place-based knowledges are shaped by underground landscapes. Further, we explore how these inform local risk perceptions of shale gas exploration. Our findings demonstrate how senses of place and place-based knowledges in each community are embedded in local rural culture that stretches back multiple generations, and are at least in part rooted in human connections to, and understanding of, the subsurface. Connections between surface and underground aspects of places create concerns about distinctiveness, which heighten residents' perceptions of more generalized shale gas risks. The research findings broaden our understanding of how places encompass both surface and underground landscapes, with significant implications for risk perceptions in energy contexts. These findings raise important questions for incorporating place-based and plural sets of knowledge in risk management and decision-making for future underground energy projects that contribute to net-zero strategies

Rocaglates induce gain-of-function alterations to eIF4A and eIF4F

Rocaglates are a diverse family of biologically active molecules that have gained tremendous interest in recent years due to their promising activities in pre-clinical cancer studies. As a result, this family of compounds has been significantly expanded through the development of efficient synthetic schemes. However, it is unknown whether all of the members of the rocaglate family act through similar mechanisms of action. Here, we present a comprehensive study comparing the biological activities of >200 rocaglates to better understand how the presence of different chemical entities influences their biological activities. Through this, we find that most rocaglates preferentially repress the translation of mRNAs containing purine-rich 5' leaders, but certain rocaglates lack this bias in translation repression. We also uncover an aspect of rocaglate mechanism of action in which the pool of translationally active eIF4F is diminished due to the sequestration of the complex onto RNA.P50 GM067041 - NIGMS NIH HHS; R24 GM111625 - NIGMS NIH HHS; R35 GM118173 - NIGMS NIH HHSPublished versio

Thermal reshaping as a route for reuse of end-of-life glass fibre-reinforced acrylic composites

Thermal reshaping has been employed to simulate the end-of-life reuse of liquid-resin-infused thermoplastic acrylic composite laminates, and the associated effects on matrix-dominated mechanical performance and microstructure have been studied. L-shaped laminates were infused at room temperature and subjected to 1 or 4 hot-press flattening cycles (25 min at 120 °C; 11 bar). Compared to the original references, up to 13% higher transverse flexural strengths were measured for the reprocessed laminates. Such a scheme may be readily implemented for high-value reuse without sacrificing fibre length scales, and with minimal cumulative mass loss over successive reheating cycles (10 cycles: 2% and 15 cycles: 2.6%). This study provides important insights to foster a greater understanding of the performance limits of hot-press reprocessing to inform the practical reuse and re-application of sustainable composites in a circular economy

Environmental stressors may cause unpredicted, notably lagged life-history responses in adults of the planktivorous Atlantic herring

Here we challenge traditional views on the direction of change in teleost body condition and reproductive traits in response to abiotic and biotic factors by studying the data-rich, planktivorous Norwegian spring-spawning herring (NSSH), a member of the abundant Atlantic herring (Clupea harengus) stock complex. To test potential influential factors, we focused on the last twenty years, i.e. a period with ocean warming, a transient but significant drop in zooplankton biomass, and accelerating interspecific competition resulting from primarily Atlantic mackerel (Scomber scombrus) entering these high-latitude waters in large quantities, “the new mackerel era” in the Nordic Seas. Adult NSSH concurrently allocated relatively less to growth in length than weight resulting in higher body condition. Growth likely decreased in warmer waters under stiff prey competition to support reproductive costs. Condition and reproductive responses were not only immediate but were also lagged by three seasons, corresponding to the period when new oocytes are produced. Furthermore, fecundity increased in warmer waters while egg size dropped. Hence, fine-tuned trade-off mechanisms were apparent and varied. We demonstrate that evaluations of reproductive trade-offs based on pooled data are misleading; poor- and good-condition NSSH followed different reproductive trajectories. These findings emphasize difficult-to-predict trends in life-history traits should be tracked longitudinally by the individuals and their aggregate cohort, as they are linked to complex overarching environmental phenomena, like ecosystem carrying capacity and climate fluctuations.publishedVersio

A model for malaria treatment evaluation in the presence of multiple species

Plasmodium (P.) falciparum and P. vivax are the two most common causes of malaria. While the majority of deaths and severe morbidity are due to P. falciparum, P. vivax poses a greater challenge to eliminating malaria outside of Africa due to its ability to form latent liver stage parasites (hypnozoites), which can cause relapsing episodes within an individual patient. In areas where P. falciparum and P. vivax are co-endemic, individuals can carry parasites of both species simultaneously. These mixed infections complicate dynamics in several ways; treatment of mixed infections will simultaneously affect both species, P. falciparum can mask the detection of P. vivax, and it has been hypothesised that clearing P. falciparum may trigger a relapse of dormant P. vivax. When mixed infections are treated for only blood-stage parasites, patients are at risk of relapse infections due to P. vivax hypnozoites. We present a stochastic mathematical model that captures interactions between P. falciparum and P. vivax, and incorporates both standard schizontocidal treatment (which targets blood-stage parasites) and radical treatment (which additionally targets liver-stage parasites). We apply this model to assess the implications of different treatment coverage of radical cure for mixed and P. vivax infections and a so-called "unified radical cure" treatment strategy for P. falciparum, P. vivax and mixed infections. We find that a unified radical cure strategy, with G6PD screening, leads to a substantially lower incidence of malaria cases and deaths overall. We perform a one-way sensitivity analysis to highlight important model parameters

Investigating the structural compaction of biomolecules upon transition to the gas-phase using ESI-TWIMS-MS

Collision cross-section (CCS) measurements obtained from ion mobility spectrometry-mass spectrometry (IMS-MS) analyses often provide useful information concerning a protein’s size and shape and can be complemented by modeling procedures. However, there have been some concerns about the extent to which certain proteins maintain a native-like conformation during the gas-phase analysis, especially proteins with dynamic or extended regions. Here we have measured the CCSs of a range of biomolecules including non-globular proteins and RNAs of different sequence, size, and stability. Using traveling wave IMS-MS, we show that for the proteins studied, the measured CCS deviates significantly from predicted CCS values based upon currently available structures. The results presented indicate that these proteins collapse to different extents varying on their elongated structures upon transition into the gas-phase. Comparing two RNAs of similar mass but different solution structures, we show that these biomolecules may also be susceptible to gas-phase compaction. Together, the results suggest that caution is needed when predicting structural models based on CCS data for RNAs as well as proteins with non-globular folds

A scoping review of mathematical models of Plasmodium vivax

Plasmodium vivax is one of the most geographically widespread malaria parasites in the world due to its ability to remain dormant in the human liver as hypnozoites and subsequently reactivate after the initial infection (i.e. relapse infections). More than 80% of P. vivax infections are due to hypnozoite reactivation. Mathematical modelling approaches have been widely applied to understand P. vivax dynamics and predict the impact of intervention outcomes. In this article, we provide a scoping review of mathematical models that capture P. vivax transmission dynamics published between January 1988 and May 2023 to provide a comprehensive summary of the mathematical models and techniques used to model P. vivax dynamics. We aim to assist researchers working on P. vivax transmission and other aspects of P. vivax malaria by highlighting best practices in currently published models and highlighting where future model development is required. We provide an overview of the different strategies used to incorporate the parasite's biology, use of multiple scales (within-host and population-level), superinfection, immunity, and treatment interventions. In most of the published literature, the rationale for different modelling approaches was driven by the research question at hand. Some models focus on the parasites' complicated biology, while others incorporate simplified assumptions to avoid model complexity. Overall, the existing literature on mathematical models for P. vivax encompasses various aspects of the parasite's dynamics. We recommend that future research should focus on refining how key aspects of P. vivax dynamics are modelled, including the accumulation of hypnozoite variation, the interaction between P. falciparum and P. vivax, acquisition of immunity, and recovery under superinfection