bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure of the CABIT2 domain of THEMIS reveals a novel protein fold with an inserted SH3-like domain
Authors: Beyett Tyler S. , Yurtsever Zeynep , Schaeffner Ilse K. , Rana Jaimin K. , Robbie Lucy K. , Ortiz-Salazar Daniela , Eck Michael J.
Published: October 2024

Maturation of thymocytes into T cells is critical for proper function of the adaptive immune system. During this developmental process, thymocytes undergo a highly-regulated selection process regulated by the signaling characteristics of the T cell receptor (TCR) pathway. Thymocyte-Expressed Molecule Involved in Selection (THEMIS) is an essential protein for T cell development. THEMIS regulates phosphatases downstream of the T cell receptor to ensure signaling thresholds are met during selection. Important features of THEMIS are its two uncharacterized CABIT (Cysteine-containing All-Beta In THEMIS) domains, which are intriguing because they have been proposed to participate in important protein-protein interactions (PPIs) that modulate immunological signals. Here, we report the 2.9 Å crystal structure of the THEMIS CABIT2 domain determined via heavy atom phasing. The structure revealed a novel protein domain fold comprised mainly of β-sheets with two distinct subdomains. This domain appears to have a different C-terminal boundary than predicted or found in previously used experimental constructs. Inclusion of the proline rich segment enables GRB2 to bind CABIT2. Isolated CABIT2 domain is unable to bind or modulate the function of SHP1 phosphatase. This structure will provide the foundation for future structure-function studies of CABIT domains and THEMIS.
Implementation challenges for an optimised surgery blueprint schedule in a children’s hospital: an exploratory qualitative study using the CFIR framework
Authors: Vos Kelly , van Essen Theresia , Ista Erwin , Staals Lonneke , Hinrichs-Krapels Saba
Published: October 2024

Capacity management and planning for operating theatres involves scheduling surgeries, preparing beds, and ensuring available workforce. Numerous mathematical models have been developed in the scientific literature to optimise these schedules to aid planning decisions, but such models are rarely assessed for applicability and implementation within a hospital’s existing planning system. We address this implementation research gap by identifying the barriers and facilitators for adopting a mathematically optimised surgery blueprint schedule within a children’s hospital, using the Consolidated Framework for Implementation Research (CFIR). Facilitators for implementation of the schedule included a strong motivation among staff to optimise schedules given resource constraints and work burdens, as well as positive reactions towards an objectively designed mathematical scheduling tool. Barriers for implementation included a resistance to change among some staff, and the need for more evidence about the new schedule’s benefits before implementation. We identified a strong culture of operational adjustments made to schedules, which is a challenge to any optimised and centralised scheduling tool. Overall, we found that CFIR was a helpful tool for identifying specific innovation adoption factors for a proposed surgery scheduling model.
Rapidly rotating quantum droplets confined in a harmonic potential
Authors: Nikolaou S. , Kavoulakis G. M. , Ögren M.
Published: October 2024

We consider a “symmetric” quantum droplet in two spatial dimensions, which rotates in a harmonic potential, focusing mostly on the limit of “rapid” rotation. We examine this problem using a purely numerical approach, as well as a semianalytic Wigner-Seitz approximation (first developed by Baym, Pethick, and their co-workers) for the description of the state with a vortex lattice. Within this approximation we assume that each vortex occupies a cylindrical cell, with the vortex-core size treated as a variational parameter. Working with a fixed angular momentum, as the angular momentum increases and depending on the atom number, the droplet accommodates none, few, or many vortices, before it turns to center-of-mass excitation. For the case of a “large” droplet, working with a fixed rotational frequency of the trap Ω, as Ω approaches the trap frequency ω, a vortex lattice forms, the number of vortices increases, the mean spacing between them decreases, while the “size” of each vortex increases as compared to the size of each cell. In contrast to the well-known problem of contact interactions, where we have melting of the vortex lattice and highly correlated many-body states, here no melting of the vortex lattice is present, even when Ω=ω. This difference is due to the fact that the droplet is self-bound. For Ω=ω, the “smoothed” density distribution becomes a flat top, very much like the static unconfined droplet. When Ω exceeds ω, the droplet maintains its shape and escapes to infinity, via center-of-mass motion.

Published by the American Physical Society
2024
Construction of superconducting dome and emergence of quantum critical region in holography
Authors: Seo Yunseok , Kim Sejin , Kim Kyung Kiu
Published: October 2024

In this work, we investigate an extended model of holographic superconductor by a nonlinear electrodynamic interaction coupled to a complex scalar field. This nonlinear interaction term can make a quantum phase transition at zero temperature with finite charge carrier density. By solving full equations of motion, we can construct various shapes of the superconducting phase in the phase diagram. With a specific choice of interaction coefficients, we can construct a phase diagram with a superconducting dome. Also, we find a new geometric solution inside the superconducting dome, which turns out to be a Lifshitz-type geometry. This geometry is characterized by a dynamical critical exponent, which plays a crucial role near the quantum critical point. We refer to this region of the phase diagram as a quantum critical region.

Published by the American Physical Society
2024
Vanishing conditions for higher order couplings in heterotic theories
Authors: Gray James
Published: October 2024

For compactifications of heterotic string theory, we elucidate simple cohomological conditions that lead to the vanishing of superpotential n-point couplings for all n. These results generalize some vanishing theorems for Yukawa couplings that have previously appeared in the literature to all higher orders. In some cases, these results are enough to show that certain fields do not appear in the perturbative superpotential at all. We illustrate our discussion with a number of concrete examples. In some cases, our results can be confirmed by showing that symmetries indeed forbid the couplings that vanish. In many, however, no such symmetries are known to exist and, as such, the infinite sets of vanishing couplings that are found are surprising from a four-dimensional perspective.

Published by the American Physical Society
2024
Impact of Nuclear Motion on Light-Induced Bimolecular Interaction Dynamics
Authors: Shi Menghang , Huang Hao , Lu Chenxu , Pan Shengzhe , Zhou Lianrong , Jiang Zhejun , Ni Hongcheng , Zhang Wenbin , Wu Jian
Published: October 2024

In chemical reactions, the nuclear motion of the molecules plays a crucial role in determining the reaction rates and outcomes. Employing the cold target recoil ion momentum spectroscopy and femtosecond pump-probe techniques, we perform a molecular-level study into the influence of nuclear vibrations on light-induced bimolecular reactions within H2−D2 dimers. The study focuses on the formation dynamics of D2H+ and H2D+ cations, shedding light on the interplay between translational and vibrational motions of the nuclei steering the bimolecular reactions. Our observations reveal a notable yield ratio of 1:1.6 between H2D+ and D2H+ channels, accompanied with a faster formation of D2H+ compared to H2D+. Molecular dynamics simulations unveil that the faster vibrational motion of H2+ than that of D2+ upon single ionization within the dimer accounts for these differences. Our findings provide new insight into the time-resolved kinetic isotope effect on the bimolecular reactions, highlighting the critical relationship between nuclear vibrational motions and reaction dynamics.

Published by the American Physical Society
2024
Exponential Learning Advantages with Conjugate States and Minimal Quantum Memory
Authors: King Robbie , Wan Kianna , McClean Jarrod R.
Published: October 2024

The ability of quantum computers to directly manipulate and analyze quantum states stored in quantum memory allows them to learn about aspects of our physical world that would otherwise be invisible given a modest number of measurements. Here we investigate a new learning resource, which could be available to quantum computers in the future—measurements on the unknown state accompanied by its complex conjugate ρ⊗ρ∗. For a certain shadow tomography task, we surprisingly find that measurements on only copies of ρ⊗ρ∗ can be exponentially more powerful than measurements on ρ⊗K, even for large K. This expands the class of provable exponential advantages using only a constant overhead quantum memory, or minimal quantum memory, and we provide a number of examples where the state ρ∗ is naturally available in both computational and physical applications. In addition, we precisely quantify the power of classical shadows on single copies under a generalized Clifford ensemble and give a class of quantities that can be efficiently learned. The learning task we study in both the single copy and quantum memory settings is physically natural and corresponds to real-space observables with a limit of bosonic modes, where it achieves an exponential improvement in detecting certain signals under a noisy background. We quantify a new and powerful resource in quantum learning, and we believe the advantage may find applications in improving quantum simulation, learning from quantum sensors, and uncovering new physical phenomena.

Published by the American Physical Society
2024
Low-dimensional metal–organic frameworks: a pathway to design, explore and tune magnetic structures
Authors: Calder Stuart , Baral Raju , Buchanan C. Charlotte , Gilbert Dustin A. , Terry Rylan J. , Kolis Joseph W. , Sanjeewa Liurukara D.
Published: October 2024

The magnetic structure adopted by a material relies on symmetry, the hierarchy of exchange interactions between magnetic ions and local anisotropy. A direct pathway to control the magnetic interactions is to enforce dimensionality within the material, from zero-dimensional isolated magnetic ions, one-dimensional (1D) spin-chains, two-dimensional (2D) layers to three-dimensional (3D) order. Being able to design a material with a specific dimensionality for the phenomena of interest is non-trivial. While many advances have been made in the area of inorganic magnetic materials, organic compounds offer distinct and potentially more fertile ground for material design. In particular magnetic metal–organic frameworks (mMOFs) combine magnetism with non-magnetic property functionality on the organic linkers within the structural framework, which can further be tuned with mild perturbations of pressure and field to induce phase transitions. Here, it is examined how neutron scattering measurements on mMOFs can be used to directly determine the magnetic structure when the magnetic ions are in a 2D layered environment within the wider 3D crystalline framework. The hydrated formate, in deuterated form, Co(DCOO)2·2D2O, which was one of the first magnetic MOFs to be investigated with neutron diffraction, is reinvestigated as an exemplar case.
Simultaneous inversion of four physical parameters of hydrate reservoir for high accuracy porosity estimation
Authors: Yan Yuning , Li Hongbing
Published: October 2024

Estimation of the porosity of a hydrate reservoir is essential for its exploration and development. However, the estimation accuracy was usually less certain in most previous studies that simply assumed that there is a linear relationship between the porosity and single‐elastic wave velocities or other rock physical parameters, thus affecting the evaluation of the reserves. In the three‐phase Biot‐type equations that are fundamental to model a hydrate‐bearing reservoir, porosity, alongside hydrate saturation, mineral constituent proportions and hydrate–grain contact factor, is non‐linearly responded by density, compressional and shear wave velocities. To improve porosity estimation, we propose to invert simultaneously four‐parameter (porosity, hydrate saturation, mineral constituent proportions and hydrate–grain contact factor) using an iteratively nonlinear interior‐point optimization algorithm to solve a nonlinear objective function that is a summation of the squared misfits between the well log and three‐phase Biot‐type equation–modelled density, compressional and shear wave velocities. A test in Mount Elbert gas hydrate research well was conducted for the case of a gas hydrate stratigraphic test well where elastic wave velocities, density, porosity and mineral composition analysis data are available. The four‐parameter inversion yielded a lower root mean square error for porosity (0.0245) across the entire well‐logging section compared to previous estimations from the linear relationship, post‐stacked and pre‐stacked seismic traces as well as the pore‐filling effective medium theory model applied to other well cases. Additionally, the other three parameters demonstrated good agreement with well logs. Inversion tests conducted at three additional hydrate sites also produced accurate results. Consequently, the new method surpasses previous approaches in porosity estimation accuracy.
Drivers of differentiation between EU Member‐states in the UN General Assembly
Authors: BLAVOUKOS SPYROS , GALARIOTIS IOANNIS
Published: October 2024

The European Union (EU) has laboured hard to gain the right to make oral interventions in the United Nations General Assembly (UNGA) in pursuit of a more active international role. At the same time, though, EU member‐states continue to take the floor to make their own interventions, thus differentiating – but not necessarily distancing – their stance from the officially expressed EU position. In that respect, it is important to examine the drivers behind the differentiating activity of EU member‐states and their engagement in UNGA deliberations. We identify structural, institutional, political and thematic drivers. They relate to resources, the EU system of external representation in the form of the EU rotating Council Presidency and the opportunities that it provides during each country's period in office, national political aspirations for greater influence, as well as issue‐specific assertiveness. We operationalize and control for these drivers by looking at the size and economic resources of EU member‐states, their individual statements while holding the EU rotating Council Presidency, their membership in the UN Security Council (UNSC) or candidacy for it, and the issue specificity of each UNGA Main Committee. Our analysis is based on a three‐level longitudinal multilevel random intercept model and relies upon a new dataset that compiles the oral interventions made by representatives of EU member‐states and by EU officials in UNGA through an automated content analysis of the verbatim records of the UNGA meetings from 1998 to 2017.
Herbicide‐resistant weed management with robots: A weed ecological–economic model
Authors: Yu Chengzheng , Khanna Madhu , Atallah Shady S. , Kar Saurajyoti , Bagavathiannan Muthukumar , Chowdhary Girish
Published: October 2024

The heavy reliance on herbicides for weed control has led to an increase in resistant weeds in the United States. Robotic weed control is emerging as an alternative technology for removing weeds mechanically using artificial intelligence. We develop an integrated weed ecological and economic dynamic (I‐WEED) model to examine the biophysical and economic drivers of adopting robotic weed management and simulate the optimal timing and intensity of robotic adoption within and across growing seasons. We specify a cohort‐based weed growth model that relates yield damages to effective weed density and treats the susceptibility of weeds to herbicides as a renewable resource that can be regenerated by using mechanical weeding robots, due to a fitness cost that makes resistant weeds less prolific. Compared to myopic weed management which ignores resistance development, forward‐looking management leads to earlier adoption of robots and treating robots as complements instead of substitutes to herbicides. This weed management results in adopting fewer robots, deploying robots on a smaller portion of the land, higher profitability, and lower yield loss in the long run, relative to myopic management. Counterintuitively, myopic management leads to a lower resistance level through its higher robot adoption intensity. We also find that a lower level of initial weed seed resistance and/or a higher fitness cost result in a higher level of resistance because they create incentives for farmers to delay the adoption of robotic weed control. Our analysis shows the importance of jointly considering the interactions between weed ecology and economics in analyzing the incentives and effects of robotic weed management on weed resistance.
Routine vaginal examination to assess labor progress at 8 compared to 4 h after early amniotomy following Foley balloon ripening in the labor induction of nulliparas: A randomized trial
Authors: Nashreen C. M. , Hamdan Mukhri , Hong Jesrine , Kamarudin Maherah , Saaid Rahmah , Tan Peng Chiong
Published: October 2024

Introduction

Our objective was to compare the performance of the first vaginal examination at 8 vs 4 h after amniotomy following Foley ripening in nulliparous labor induction.

Material and Methods

A randomized controlled trial was conducted from June 2021 to January 2022. 210 nulliparas at term for labor induction were randomized: 105 each to first vaginal examination at 8 or 4 h after Foley balloon ripening and amniotomy. Titrated oxytocin infusion was routinely commenced after amniotomy to expedite labor. Primary outcomes were the amniotomy‐to‐delivery interval (non‐inferiority hypothesis) and maternal satisfaction with their allocated labor care (superiority hypothesis) within 24 h after delivery. Analyses performed using t‐test, Mann–Whitney U test, and Chi‐squared test as appropriate.

Results

The amniotomy‐to‐delivery interval was mean ± standard deviation 8.7 ± 3.4 vs 8.4 ± 3.7, mean difference 0.4 (97.5% CI: −0.7 to 1.5) hours, p = 0.442 within the pre‐specified 2‐hour non‐inferiority margin, and maternal satisfaction score with allocated labor care was median [interquartile range] 8[7.5–10] vs 8[7.0–10], p = 0.248 for 8 vs 4 h arms, respectively. The amniotomy to first vaginal examination intervals was 5.9 ± 2.3 vs 3.6 ± 1.0 h, p < 0.001, and the number of vaginal examinations was 2[1–2.5] vs 3 [2, 3], p < 0.001 for 8 vs 4 h, respectively. The first vaginal examination was less likely to have been performed as scheduled, more likely to be indicated by the urge to bear down, and non‐reassuring cardiotocography for the 8 h arm (p < 0.001). Spontaneous vaginal delivery was significantly more likely and instrumental vaginal delivery less likely, but cesarean rate was not significantly different for the 8 h arm (p = 0.017).

Conclusions

A routine first vaginal examination at 8 h compared to 4 h is non‐inferior for the time to birth but does not increase maternal satisfaction although the number of vaginal examinations is fewer. The increase in spontaneous vaginal delivery and reduction in instrumental vaginal delivery rates warrant further powered primary evaluation.
A full‐factorial test of motivational and volitional intervention strategies for promoting exercise habit formation and exercise maintenance among new users of an online exercise class platform
Authors: Phillips L. Alison , More Kimberly R. , Lamoureux Nicholas R. , Dixon Philip M. , Meyer Jacob D. , Ellingson Laura , Welk Greg , Hastings Bryce
Published: October 2024

Interventions often fail to achieve long‐term behavioral maintenance. Utilizing motivational and volitional strategies to promote behavioral maintenance factors may improve this. Using a full‐factorial experiment, we tested the effects of three intervention components (focused on intrinsic motivation and identity, exercise preparation habit, and exercise instigation habit) on exercise participation over a year, among new users (N = 751; 91% identifying as female, 54% identifying as White race) of a global, online exercise class platform, run by Les Mills International Ltd, called LM+. We also tested the intervention components' theoretical mechanisms of action—habit formation, intrinsic motivation, identity, and self‐efficacy. Multi‐level models found some support for a main effect of the exercise preparation habit intervention component in promoting self‐reported and objective exercise participation (behavioral outcomes measured via monthly surveys and the LM+ platform; mechanisms measured via monthly surveys)—in particular online exercise class frequency (fixed effect estimate = 0.84, p < 0.05, and = 0.12, p < 0.05, respectively). The preparation habit component also significantly increased preparation habit strength (0.30, p < 0.05) and instigation habit strength (0.33, p < 0.05). Other expected effects were nonsignificant. Helping individuals form an exercise preparation habit may facilitate initiating and maintaining exercise over time, in particular for attending online exercise classes, potentially through promoting greater preparation and exercise instigation habit strength.
Individual preferences in multiple goal pursuit: Reconsidering the conceptualization and dimensionality of polychronicity
Authors: Yang Zhixu (Rick) , Kung Franki Y. H. , Schneider Darryl W.
Published: October 2024

With increasing demands in work and life, successful self‐regulation of multiple goals becomes critical to the well‐being and performance of individuals and organizations. When pursuing multiple goals, individuals may use different strategies and have divergent preferences toward these strategies. Polychronicity, or the preference for multitasking over sequential tasking, has long been considered a unidimensional construct with two opposing ends. To empirically test this assumption, we reconstructed existing polychronicity items to explore a new scale that measures preferences separately and synthesizes different operationalizations of multitasking (i.e., concurrent tasking and task switching) (study 1). We found that multitasking and sequential preferences, while related, have distinct components and can co‐occur within individuals, challenging the traditional bipolar assumption (study 2). Finally, we used a behavioral task‐switching paradigm to simulate a multitasking environment. We found that consistent with past research, the preferences were not associated with behavioral performance but were associated with subjective experience (study 3). Our findings suggest that assuming multitasking and sequential preferences are completely antithetical can be an oversimplification. This research opens opportunities for future research on multiple goals.
The effect of daily leader secure‐base support on employees' daily performance: An attachment theory perspective
Authors: Dong Niannian , Xing Lu (Lucy) , Zhang Yejun (John) , Sheldon Oliver J. , Yin Kui , Hu Xiaoran , Zhang Long
Published: October 2024

Drawing on attachment theory, the present study develops a theoretical model to explore whether, how, and when daily leader secure‐base support impacts employees' daily in‐role and extra‐role performance. To test this model, we employed an experience‐sampling method and collected daily diary data over 3 weeks. Results of multilevel path analysis indicated that daily leader secure‐base support was positively related to both employees' daily in‐role and extra‐role performance. Moreover, we found that daily leader secure‐base support indirectly influenced employees' in‐role performance via their self‐esteem, whereas it indirectly influenced employees' extra‐role performance via their gratitude. Finally, attachment anxiety moderated the within‐person relationship between daily leader secure‐base support and employees' self‐esteem as well as the indirect effect of daily leader secure‐base support on employees' subsequent in‐role performance via their self‐esteem. We discuss the theoretical and practical implications of these findings, as well as future research directions.
Matrix stiffness regulates mitochondria‐lysosome contacts to modulate the mitochondrial network, alleviate the senescence of MSCs
Authors: Wang Kang , Ho Chingchun , Li Xiangyu , Hou Jianfeng , Luo Qipei , Wu Jiahong , Yang Yuxin , Zhang Xinchun
Published: October 2024

The extracellular microenvironment encompasses the extracellular matrix, neighbouring cells, cytokines, and fluid components. Anomalies in the microenvironment can trigger aging and a decreased differentiation capacity in mesenchymal stem cells (MSCs). MSCs can perceive variations in the firmness of the extracellular matrix and respond by regulating mitochondrial function. Diminished mitochondrial function is intricately linked to cellular aging, and studies have shown that mitochondria‐lysosome contacts (M‐L contacts) can regulate mitochondrial function to sustain cellular equilibrium. Nonetheless, the influence of M‐L contacts on MSC aging under varying matrix stiffness remains unclear. In this study, utilizing single‐cell RNA sequencing and atomic force microscopy, we further demonstrate that reduced matrix stiffness in older individuals leads to MSC aging and subsequent decline in osteogenic ability. Mechanistically, augmented M‐L contacts under low matrix stiffness exacerbate MSC aging by escalating mitochondrial oxidative stress and peripheral division. Moreover, under soft matrix stiffness, cytoskeleton reorganization facilitates rapid movement of lysosomes. The M‐L contacts inhibitor ML282 ameliorates MSC aging by reinstating mitochondrial network and function. Overall, our findings confirm that MSC aging is instigated by disruption of the mitochondrial network and function induced by matrix stiffness, while also elucidating the potential mechanism by which M‐L Contact regulates mitochondrial homeostasis. Crucially, this presents promise for cellular anti‐aging strategies centred on mitochondria, particularly in the realm of stem cell therapy.
Investigating the impact of postponement and stock‐sharing strategies on prepositioned relief stocks
Authors: Kasap‐Şimşek Lamia Gülnur , Balcik Burcu , Chané Florent
Published: October 2024

Prepositioning is a critical disaster preparedness mechanism for humanitarian organizations (HOs) but requires significant investment. Improving the efficiency of prepositioned stocks is a primary concern within the humanitarian community. This study, conducted in collaboration with the Emergency Supply Prepositioning Strategy (ESUPS) Working Group, examines the impact of implementing postponement and stock‐sharing strategies in a regional humanitarian warehouse. We focus on a setting where multiple HOs preposition supplies within the same warehouse to serve disaster‐affected countries. Traditionally, these prepositioned supplies are branded with the respective HOs' logos, hindering the sharing of surplus stock during disaster response. Our system defers the branding process for a portion of the stockpile until after a disaster, facilitating the sharing of unbranded stock among HOs. To evaluate the benefits of postponement in this humanitarian context, we develop a two‐phase inventory allocation framework for distributing branded and unbranded stocks to disaster‐affected countries and for sharing unbranded stocks among HOs. We then incorporate our inventory allocation models into a Monte Carlo simulation algorithm that accounts for uncertainties regarding the occurrence and impact of disasters. Using a case study based on data from ESUPS members in the Caribbean region, we demonstrate that the proposed strategy can significantly enhance the efficiency and effectiveness of prepositioning. Remarkably, we observe a U‐shaped relationship in response time as the postponement rate increases, while the fill rate and inventory utilization consistently improve. Our numerical study provides valuable insights for decision making in humanitarian logistics.
Plant–Soil Moisture Positive Feedback Maintaining Alternative Stable States in the Alpine Marsh Ecosystem
Authors: Hu Guorui , Bai Haonan , Zhao Yunpeng , Chen Ning , Li Honglin , Mao He , Guo Zengpeng , Sheng Xiongjie , Zhang Hui , An Hang , Zhang Panhong , Zhang Zhengkuan , Sun Yinguang , Ma Miaojun
Published: October 2024

A self‐reinforcing positive feedback is regarded as a critical process for maintaining alternative stable states (ASS); however, identification of ASS and quantification of positive feedbacks remain elusive in natural ecosystems. Here, we used large‐scale field surveys to search for ASS and a positive feedback mechanism under a wide range of habitats on the Tibetan Plateau. Using multiple methods, we proved that three stable states exist that accompany alpine marsh degradation. Positive feedbacks between changing soil moisture and plant community composition forced the ecosystem into another stable state, and the alteration of water use efficiency (WUE) of the component species contributed to this shift. This study provides the first empirical evidence that positive feedback loops maintain ASS in the alpine marsh ecosystem on the Tibetan Plateau. Our research revealed the powerful driving role of plants in transitions between states, which may support the conservation and restoration of global alpine marsh ecosystems.
Asymmetric Biotic Interactions Cannot Be Inferred Without Accounting for Priority Effects
Authors: Powell‐Romero Francisca , Wells Konstans , Clark Nicholas J.
Published: October 2024

Understanding biotic interactions is a crucial goal in community ecology and species distribution modelling, and large strides have been made towards improving multivariate computational methods with the aim of quantifying biotic interactions and improving predictions of species occurrence. Yet, while considerable attention has been given to computational approaches and the interpretation of these quantitative tools, the importance of sampling design to reveal these biotic interactions has received little consideration. This study explores the influential role of priority effects, that is, the order of habitat colonisation, in shaping our ability to detect biotic interactions. Using a simple set of simulations, we demonstrate that commonly used cross‐sectional co‐occurrence data alone cannot be used to make reliable inferences on asymmetric biotic interactions, even if they perform well in predicting the occurrence of species. We then show how sampling designs that consider priority effects can recover the asymmetric effects that are lost when priority effects are ignored. Based on these findings, we urge for caution when drawing inferences on biotic interactions from cross‐sectional binary co‐occurrence data, and provide guidance on sampling designs that may provide the necessary data to tackle this longstanding challenge.
Deep‐Pelagic Fishes Are Anything But Similar: A Global Synthesis
Authors: Eduardo Leandro Nolé , Mincarone Michael Maia , Sutton Tracey , Bertrand Arnaud
Published: October 2024

Deep‐pelagic fishes are among the most abundant vertebrates on Earth. They play a critical role in sequestering carbon, providing prey for harvestable fishing stocks and linking oceanic layers and trophic levels. However, knowledge of these fishes is scarce and fragmented, hampering the ability of both the scientific community and stakeholders to address them effectively. While modelling approaches incorporating these organisms have advanced, they often oversimplify their functional and ecological diversity, potentially leading to misconceptions. To address these gaps, this synthesis examines the biodiversity and ecology of global deep‐pelagic fishes. We review pelagic ecosystem classifications and propose a new semantic framework for deep‐pelagic fishes. We evaluate different sampling methods, detailing their strengths, limitations and complementarities. We provide an assessment of the world's deep‐pelagic fishes comprising 1554 species, highlighting major groups and discussing regional variability. By describing their morphological, behavioural and ecological diversity, we show that these organisms are far from homogeneous. Building on this, we call for a more realistic approach to the ecology of deep‐pelagic fishes transitioning between very different ecological niches during diel vertical migrations. To facilitate this, we introduce the concept of ‘diel‐modulated realised niche’ and propose a conceptual model synthesising the multiple drivers responsible for such transitions.
Pre‐Copulatory Sexual Selection Predicts Sexual Size Dimorphism: A Meta‐Analysis of Comparative Studies
Authors: Winkler Lennart , Freckleton Robert P. , Székely Tamás , Janicke Tim
Published: October 2024

Size differences between males and females are common across the tree of life (termed sexual size dimorphism; SSD), and have fundamental implications for ecology, life history and behaviour of both sexes. Conventionally, SSD is thought to evolve in response to sex‐specific sexual selection but more recent work suggests that ecological processes can also promote sex‐differences in size. Here, we provide a global test for the role of sexual selection in the evolution of sexual size dimorphism using data from 77 comparative studies spanning the major classes of the animal kingdom. We show that intense sexual selection typically correlates with male‐biased SSD across species. Importantly, pre‐copulatory but not post‐copulatory sexual selection predicts SSD, suggesting a pervasive role of premating male–male competition and female choice to drive sex differences in body size. Collectively, our findings suggest that pre‐copulatory sexual selection plays a major role in the evolution of male‐biased SSD.
Decoding Information Flow and Sensory Pollution: A Systematic Framework for Understanding Species Interactions
Authors: Li Jingyi , Brose Ulrich , Rosenbaum Benjamin , Ryser Remo , Berti Emilio
Published: October 2024

Information transmission among species is a fundamental aspect of natural ecosystems that faces significant disruption from rapidly growing anthropogenic sensory pollution. Understanding the constraints of information flow on species' trophic interactions is often overlooked due to a limited comprehension of the mechanisms of information transmission and the absence of adequate analytical tools. To fill this gap, we developed a sensory information‐constrained functional response (IFR) framework, which accounts for the information transmission between predator and prey. Through empirical evaluation, the IFR provided a biologically grounded explanation for the systematic variation of functional responses. Specifically, it posits that the variation of different functional‐response shapes, associated with community stability, is attributable to limitations in sensory information transmission among species. This not only deepens our mechanistic understanding of species interactions but also elucidates how anthropogenic activities are reshaping species interactions and community dynamics by disrupting information exchange through sensory pollution.
Wind Shapes the Growth Strategies of Trees in a Tropical Forest
Authors: Jackson Toby D. , Bittencourt Paulo , Poffley Jakob , Anderson Juliet , Muller‐Landau Helene C. , Ramos Pablo A. R. , Rowland Lucy , Coomes David
Published: October 2024

In tropical forests, trees strategically balance growth patterns to optimise fitness amid multiple environmental stressors. Wind poses the primary risk to a tree's mechanical stability, prompting developments such as thicker trunks to withstand the bending forces. Therefore, a trade‐off in resource allocation exists between diameter growth and vertical growth to compete for light. We explore this trade‐off by measuring the relative wind mortality risk for 95 trees in a tropical forest in Panama and testing how it varies with tree size, species and wind exposure. Surprisingly, local wind exposure and tree size had minimal impact on wind mortality risk; instead, species wood density emerged as the crucial factor. Low wood density species exhibited a significantly greater wind mortality risk, suggesting a prioritisation of competition for light over biomechanical stability. Our study highlights the pivotal role of wind safety in shaping the life‐history strategy of trees and structuring diverse tropical forests.
Characterization of a membrane toxin‐antitoxin system, tsaAT, from Staphylococcus aureus
Authors: Kato Fuminori , Bandou Risa , Yamaguchi Yoshihiro , Inouye Keiko , Inouye Masayori
Published: October 2024

Bacterial toxin‐antitoxin (TA) systems consist of a toxin that inhibits essential cellular processes, such as DNA replication, transcription, translation, or ATP synthesis, and an antitoxin neutralizing their cognate toxin. These systems have roles in programmed cell death, defense against phage, and the formation of persister cells. Here, we characterized the previously identified Staphylococcus aureus TA system, tsaAT, which consists of two putative membrane proteins: TsaT and TsaA. Expression of the TsaT toxin caused cell death and disrupted membrane integrity, whereas TsaA did not show any toxicity and neutralized the toxicity of TsaT. Furthermore, subcellular fractionation analysis demonstrated that both TsaA and TsaT localized to the cytoplasmic membrane of S. aureus expressing either or both 3xFLAG‐tagged TsaA and 3xFLAG‐tagged TsaT. Taken together, these results demonstrate that the TsaAT TA system consists of two membrane proteins, TsaA and TsaT, where TsaT disrupts membrane integrity, ultimately leading to cell death. Although sequence analyses showed that the tsaA and tsaT genes were conserved among Staphylococcus species, amino acid substitutions between TsaT orthologs highlighted the critical role of the 6th residue for its toxicity. Further amino acid substitutions indicated that the glutamic acid residue at position 63 in the TsaA antitoxin and the cluster of five lysine residues in the TsaT toxin are involved in TsaA's neutralization reaction. This study is the first to describe a bacterial TA system wherein both toxin and antitoxin are membrane proteins. These findings contribute to our understanding of S. aureus TA systems and, more generally, give new insight into highly diverse bacterial TA systems.
Shaping linguistic input in parent‐infant interactions: The influence of the Infant's temperament
Authors: Götz Antonia , Altuntas Eylem , Kalashnikova Marina , Best Catherine , Burnham Denis
Published: October 2024

Parent‐infant interactions highlight the role of parental input, considering both the quality, infant‐directed speech, and quantity of interactions, adult words and communicative turns, in these interactions. However, communication is bidirectional, yet little is known about the infant's role in these interactions. This study (n = 35 4‐month‐old infants) explores how infant‐directed speech, the number of adult words and turn‐taking (both measured by the LENA system) are correlated with infants' temperament. Our findings reveal that, while mothers use the typical characteristics of infant‐directed speech, they are not correlated with the infant's temperament. However, we observe more adult‐infant turn‐taking in both introverted infants (with lower Surgency scores) and infants with lower attention regulation (with lower Regulatory/Orienting scores). The number of adult words was not correlated with infants' temperament. We suggest that infants with an introverted temperament prefer quieter exchanges that may lead to more turns and that infants with lower attention regulation might create more opportunities for interactions due to their lower level of self‐regulation. These findings suggest that infants' temperament is associated with how adults talk with infants (communicative turns) rather than how adults talk to infants (infant‐directed speech, number of adult words). Our results underscore the infant's role in parent‐infant communication.
Mobile People in Closed Networks? Complementary Methods of Studying Social Simultaneity in Transnational Settings
Authors: Sava Ionel N.
Published: October 2024

Social simultaneity describes individuals active in multiple social contexts. Migrant networks serve as a case study where social network analysis (SNA) has recently been applied to evaluate their assimilation and transnationality. Yet, networks are sometimes insubstantial, as all nominated nodes and bridges are part of the network graph except they are not part of the social grouping. This research attempts to look beyond the social networks metaphor as it reviews critical group size theory and complements SNA with network survey and ethnographic interpretation. The article questions the structural approach and argues that interaction among alters may not be accurately recorded by this method. A respondent‐driven sampling method was used to select and survey 55 egocentric networks out of some 248 Romanian migrant networks in Spain. Results endorse precautions of critical group size theory that do not fit prescriptions of SNA. Resilient social networks and strong reciprocity and exchanges support the moderate transnational space types within the surveyed case. The article concludes that smooth social embeddedness and neoteric cultural diversity eventually reveal characteristics of third‐generation migration in Europe. Despite this, the number of Romanians in Spain decreased at the end of COVID‐19 pandemic.
Exploring Emotional Well‐Being and Support of Midwives Who Provide Termination of Pregnancy Care: An International Survey
Authors: Armour Susanne , Keedle Hazel , Gilkison Andrea , Dahlen Hannah Grace
Published: October 2024

Aims

Assess the psychological impact that providing TOP care beyond 12 weeks gestation has on midwives in Australia and New Zealand, improve understanding of TOP care and explore what support midwives have and what they might need to deal with their work experiences.

Design

Online survey.

Methods

A web‐based, self‐reported questionnaire with a total of 63 questions collected data from June to October 2022. Two validated psychometric tools were included to assess emotional well‐being. Numerical data were analysed using descriptive statistics, frequencies, percentages and means. The STROBE guideline was used for reporting.

Results

Most midwives felt unsupported and affected by their experiences of providing termination of pregnancy care. Recognition and regular post‐care debriefing with management were minimal. Lack of staff impacted the ability to provide individualised care. Mental health support was not commonly offered to midwives. Psychometric tools showed burnout and high levels of compassion fatigue, but also compassion satisfaction. To feel supported midwives need a fully staffed workforce, the ability to provide one‐on‐one care, recognition from managers and team support.

Conclusion

Midwives who deliver termination of pregnancy care are unsupported and at high risk of burnout and compassion fatigue. Providing appropriate support is vital to increase midwives' well‐being and sustain women's access to safe, high‐quality care.

Impact

Study addresses a knowledge gap about midwives' support needs when caring for women undergoing termination of pregnancy beyond 12 weeks.

Findings show the urgent need to recruit and retain midwifery staff, acknowledge the mental health risks of termination of pregnancy care and implement mental health strategies for midwives.

Research benefits midwives who provide termination of pregnancy care, midwife managers, healthcare organisations and professional bodies.

Patient or Public Contribution

No patient or public involvement.
Charting the Course of the Nursing Professional Identity: A Qualitative Descriptive Study on the Identity of Nurses Working in Care for Older Adults
Authors: Bolt Ester Ellen Trees , Chee Shi Yin , van der Cingel Margreet
Published: October 2024

Aims

To explore and describe the meaning of nurses working in care for older adults give to the nursing professional identity.

Design

A qualitative approach was taken.

Methods

Semi‐structured interviews were conducted with 50 bachelor and vocational‐educated nurses working in care for older adults. Interviews were conducted between December 2019 and May 2020. Data were analysed and interpreted through inductive content analysis.

Results

Five themes embody the meaning of the nursing professional identity of nurses who work in care for older adults. The five themes are: born to care: a lifelong motivation to nursing; nursing through the noise: dedication in a demanding profession; the silent backbone: caught in the crossfire of interdisciplinary teams; learning under pressure: the demand for expanded nursing expertise and against the current: the barriers to advocacy in nursing.

Conclusion

The professional nursing identity of nurses working in care for older adults is multi‐faceted. A personal dedication to patient care, where patients ‘human’ aspect is heavily valued, commits nurses to their profession and underscores their dedication to upholding the quality standard in nursing practice.

Implications for the Profession

The older adults' nursing identity highlights that nursing deserves acknowledgement as a professional occupation. Nurses should speak to the public about their professional roles to improve the public view of older adult nursing.

Impact

A clear understanding of the older adult nursing professional identity clarifies specific roles, experiences and expectations. This can help attract and retain nurses whose views of older adult nursing align with the nursing professional identity. This could help resolve nurse turnover and reduce shortages in older adult care.

Reporting Method

We adhered to Consolidated Criteria For Reporting Qualitative Research guidelines.

Patient or Public Contribution

No patient or public contribution.
Effects of a Protease Inhibitor Protein on Buchnera aphidicola and Gene Expression in Pea Aphids (Acyrthosiphon pisum)
Authors: Zhang Tingting , Li Qiannan , Zheng Li , Mao Jianjun , Zeng Fanrong
Published: October 2024

Aphids are serious insect pests for agricultural and horticultural crops and may cause the major economic losses. Insecticides used to control aphids have caused environmental pollution and the insecticide residues in agricultural products. A new protease inhibitor gene from bacterium Xenorhabdus bovienii (Xbpi‐1) and the protease inhibitor protein expressed by the gene against the pea aphid (Acyrthosiphon pisum Harris; Hemiptera: Aphididae) have been reported, however, effects of the PIP on the symbiotic bacteria, Buchnera aphidicola, and gene expression in pea aphids are unknown. By assessing the quantity of B. aphidicola, the primary symbiotic bacterium, in the aphid fed on an artificial diet containing 100 and 500 μg/mL Xbpi‐1, we observed a substantial reduction in its population by 27% and 46%, respectively, as analysed by real‐time quantitative reverse transcription PCR (qRT‐PCR). Furthermore, the growth of other aphid‐associated bacteria was also significantly inhibited by Xbpi‐1. To elucidate the mechanisms at the gene level, we conducted transcriptome analysis and identified differentially expressed genes (DEGs). Subsequent Gene Ontology (GO) analysis of the 213 DEGs shed light on the impact of Xbpi‐1 on aphid metabolism processes and gene expression. Notably, the results highlighted several aphid nutrient metabolism pathways affected by Xbpi‐1, which are relevant to vector‐borne diseases. These pathways encompass crucial factors such as heat shock proteins, cuticle proteins and proteases. The results from this study revealed that the PIP had a novel mechanism against pea aphids by having adverse effects on the primary symbiotic bacteria in pea aphids and affecting aphid gene expression, showing that the PIP may be a promise bioinsecticide for aphid control in the future.