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We present a lattice QCD calculation of the hadronic form factors for the semileptonic decays B→π and B(s)→D(s)ℓν, computed using the highly improved staggered quark action for both valence and sea quarks on the MILC collaboration’s 2+1+1-flavor ensembles with lattice spacings ranging from 0.09fm to 0.03fm, many with physical pion masses. On our finest ensembles, we compute the form factors directly at the physical b-quark mass. We discuss the computational setup and analysis strategies for two- and three-point correlation functions. For B(s)→D(s), we present preliminary results of chiral-continuum fits for the scalar and vector form factors. The goal of this project is a percent-level determination of the scalar and vector form factors to enable high-precision determinations of |Vub| and|Vcb|. This work fits into a broader program of lattice-QCD studies of weak B-meson decays by the MILC and Fermilab Lattice collaborations. 

We present the status of calculations of the form factors of the most relevant heavy-to-heavy and heavy-to-light decay channels. Using seven Nf=2+1+1 HISQ ensembles, with lattice spacings ranging from 0.15 fm down to 0.06 fm, we calculate the form factors of the decays, including correlations among them. More than half of our ensembles feature physical pion masses, and the heavy quarks are simulated at their physical masses using the Wilson-clover action with the Fermilab interpretation. Even though we have recently seen huge qualitative and quantitative leaps in the characterization of heavy-to-heavy decays, these advances have failed to translate into improvements for the inclusive vs exclusive question, or the matter of the Lepton Flavor Universality ratios. In particular, in the B→D∗ℓν channel, the current situation of the lattice-QCD form factors is far from clear. Further, the latest lattice-QCD results on the heavy-to-light form factors display unexplained tensions that must urgently be resolved. The work presented here is an attempt to address these issues. 

Precision tests of the Standard Model (SM) currently show a deficit in first-row Cabibbo-Kobayashi-Maskawa (CKM) unitarity. In this talk, we discuss progress towards a correlated analysis of the lattice-QCD inputs needed to test this relation with kaon data using highly improved staggered quarks (HISQ) on the MILC Nf=2+1+1 configurations. We present the status of a new analysis of light-meson decay constant data where chiral-continuum fits are guided by staggered chiral perturbation theory (SChPT). The goal of SChPT is twofold: it allows us to use data not only at physical pion mass but also at unphysical masses. Moreover, it provides values of ChPT low energy constants (LECs) as well as their correlations. We also present a reanalysis of our previous kaon semileptonic form factor calculation, aiming to estimate correlations between the form factor and light-meson decay constants. We discuss the new methodology, new data included, and present some preliminary results. 

Precision tests of the Standard Model (SM) currently show a deficit in first-row Cabibbo-Kobayashi-Maskawa (CKM) unitarity. In this talk, we discuss progress towards a correlated analysis of the lattice-QCD inputs needed to test this relation with kaon data using highly improved staggered quarks (HISQ) on the MILC Nf=2+1+1 configurations. We present the status of a new analysis of light-meson decay constant data where chiral-continuum fits are guided by staggered chiral perturbation theory (SChPT). The goal of SChPT is twofold: it allows us to use data not only at physical pion mass but also at unphysical masses. Moreover, it provides values of ChPT low energy constants (LECs) as well as their correlations. We also present a reanalysis of our previous kaon semileptonic form factor calculation, aiming to estimate correlations between the form factor and light-meson decay constants. We discuss the new methodology, new data included, and present some preliminary results. 

Abstract The idea that organisms benefit by acquiring information through social connections is a cornerstone of our understanding of social evolution and collective behaviour. Yet, while learning about the world through social ties can confer many benefits, these connections can also serve as conduits for misinformation. Studies of misinformation in human social systems are rapidly proliferating, yet our understanding of the biological origins of misinformation remains surprisingly limited. In this review, we survey examples of socially transmitted misinformation across biological systems. Our central findings are (i) that the transmission and use of misinformation is widespread in biological systems spanning levels of organization, and (ii) that the production and transmission of misinformation is probably an inevitable property that inherits from fundamental constraints on biological communication systems, rather than a pathology that lies apart from the normal functioning of such systems. In this light, we argue that there is a need for a more integrated theoretical and empirical science of misinformation in biology. We end by highlighting four emerging questions about misinformation and its role in driving ecological and evolutionary dynamics that this new field of inquiry should address. 

Wepresentpreliminaryresultsfromalattice-QCDstudyofthehadroniccontributionstotherun- ningoftheelectromagneticcoupling,Δ𝛼(𝑄2),andtheelectroweakmixingangle,Δsin2 𝜃W(𝑄2). Using 𝑁𝑓=2 +1 +1 HISQensemblesatphysicalquarkmasses,wediscussthechallengesposed by strong statistical correlations in the time-momentum representation and propose a spectral- reconstruction strategy to obtain controlled continuum-extrapolated results across the full energy range. 

Aim: As climate warms, contemporary tree regeneration patterns will affect future forest composition. Yet the factors influencing forest regeneration across environmental gradients remain difficult to disentangle. We studied how conspecific canopy tree dominance (as a proxy for seed availability) interacts with microsite factors along elevational climatic gradients to affect regeneration patterns and recruitment limitations across temperate deciduous and montane boreal forests. Location: Adirondack and Appalachian Mountains (NY, VT, NH, and ME), USA. Taxa: Abies balsamea, Acer saccharum, Betula alleghaniensis, B. papyrifera var. cordifolia, Fagus grandifolia, and Picea rubens. Methods: We measured overstory tree dominance (via species-specific basal area), understory seedling abundance, and microsite factors (e.g., understory vegetation cover, canopy openness) across elevation on ten mountains. Generalised linear regression models were fit to quantify the importance of conspecific tree basal area (representing seed availability), microsite factors, and their interaction on recruitment for each species along elevational climatic gradients. Results: Seedling abundance increased with greater conspecific adult basal area (i.e., overstory-understory relationships were positive) for all species except the shade-intolerant and wind-dispersed B. papyrifera var. cordifolia. Sparse understory vegetation amplified positive overstory-understory relationships for A. saccharum and B. alleghaniensis, while closed canopies dampened them for the shade-intolerant B. alleghaniensis and B. papyrifera var. cordifolia. The positive overstory-understory relationship for F. grandifolia was weaker in warmer microclimates, while that for the shade-tolerant A. balsamea was greater under closed canopies, likely owing to seedling banks. Main Conclusions: Nearly ubiquitous positive overstory-understory relationships indicated that local conspecific adult tree dominance drives recruitment (likely through seed dispersal) as expected. However, microsite conditions interacted with overstory basal area and modified these overstory-understory relationships differently for each species to either inhibit or facilitate tree recruitment. This framework integrates broad-scale density-dependent processes (i.e., overstory-understory conspecific relationships) with fine-scale drivers to better understand tree species recruitment across biome boundaries. 

Abstract Private woodland owners (PWOs) face an increasing number of considerations for climate change adaptation and mitigation activities in their forest management. Evidence suggests there may be a disconnect between PWOs’ climate change perceptions and behaviors, which can limit implementation. We conducted seventeen semistructured interviews in Maine to develop a typological framework of PWOs based on their perceptions of climate-induced threats and efficacy. Our results produced three types of PWOs: the steady-as-they-go landowner (low perceived threat), the science-driven landowner (high perceived threat; high efficacy), and the seeking-support landowner (high perceived threat; low efficacy). Although all three types of PWOs regularly implemented resistance and resilience practices, their attitudes toward transition practices (i.e., assisted migration) diverged based on their perceptions of threat and efficacy. This typological framework can be used when targeting communications to PWOs regarding the overlap between climate adaptive management and traditional best management practices. Study Implications: PWOs in our study recognized climate-related impacts while implementing diverse forest management practices to meet both climate-related and non-climate-related objectives. The divergent attitudes toward transition practices exhibited by our three PWO types highlight the notion that adaptive practices can be both intentional and incidental. Our findings suggest that outreach efforts should understand PWO perceptions of climate change threats and their feelings of efficacy in responding to such threats. When combined with knowledge about the overlap between traditional best management practices and new climate-adaptive strategies, extension and outreach efforts can tailor their messaging to fit the appropriate audience. 

Accurately predicting protein behavior across diverse pH environments remains a significant challenge in biomolecular simulations. Existing constant-pH molecular dynamics (CpHMD) algorithms are limited to fixed-charge force fields, hindering their application to biomolecular systems described by permanent atomic multipoles or induced dipoles. This work overcomes these limitations by introducing the first polarizable CpHMD algorithm in the context of the Atomic Multipole Optimized Energetics for Biomolecular Applications (AMOEBA) force field. Additionally, our implementation in the open-source Force Field X (FFX) software has the unique ability to handle titration state changes for crystalline systems including flexible support for all 230 space groups. The evaluation of constant-pH molecular dynamics (CpHMD) with the AMOEBA force field was performed on 11 crystalline peptide systems that span the titrating amino acids (Asp, Glu, His, Lys, and Cys). Titration states were correctly predicted for 15 out of the 16 amino acids present in the 11 systems, including for the coordination of Zn2+ by cysteines. The lone exception was for a HIS-ALA peptide where CpHMD predicted both neutral histidine tautomers to be equally populated, whereas the experimental model did not consider multiple conformers and diffraction data are unavailable for rerefinement. This work demonstrates the promise polarizable CpHMD simulations for pKa predictions, the study of biochemical mechanisms such as the catalytic triad of proteases, and for improved protein–ligand binding affinity accuracy in the context of pharmaceutical lead optimization.