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Metrological approach to the emergence of classical objectivity
No full textWe present a precise characterization of the onset of classicality that combines the formalism of quantum Darwinism with the tools from quantum metrology. We show that the quantum Fisher information provides a useful metric for assessing the rate at which classical objectivity emerges. Furthermore, our formalism allows us to explore how the choice of measurement impacts the precision with which an observer can determine the state of the system. For a paradigmatic example of the spin-star model, we demonstrate that optimal measurements lead to the emergence of classicality at an exponential rate. Although other measurements necessarily lead to slower emergence, we importantly show that suboptimal measurements can still saturate the Cramér-Rao bound. By recasting emergent classicality as an information acquisition protocol, our framework provides a precise operational description of quantum Darwinism.AK, SD, and SC acknowledge the support of the John Templeton Foundation under Grant No. 62422. DAC acknowledges support from the “Italian National Quantum Science and Technology Institute (NQSTI)” (PE0000023) - SPOKE 2 through project ASpEQCt. A.T. is supported by the U.S DOE under the LDRD program at Los Alamoshttp://arxiv.org/abs/2510.1231
Oyster Restoration under the 2014 Chesapeake Bay Watershed Agreement: Three Takeaways for Success in Environmental Betterment Efforts
No full textFor decades, the Chesapeake Bay has suffered from a multitude of environmental issues, including the dramatically reduced population of its native eastern oyster (Crassostrea virginica). Primarily due to the proposed environmental and economic benefits a restored bay oyster population could provide to the region; there have been multiple federally-led oyster restoration projects in the bay since the 1980s. The most recent large-scale federally-led project, the oyster outcome of the 2014 Chesapeake Bay Watershed Agreement, set a goal of restoring ten tributaries’ oyster population, five in Maryland and five in Virginia. As of 2025, the Ten Tributary Project is on track to meet its criteria for restoration success in these tributaries while performing oyster restoration at an unprecedented scale for both the U.S. and the broader globe. This thesis asks how and why the 2014 oyster outcome has met its oyster restoration goals while preceding agreements under the CBP could not. After interviewing restoration officials affiliated and/or contributing to the 2014 oyster outcome, I argue three components as key to the project’s success among other less successful outcomes in the 2014 Agreement: pragmatism in the planning stage, continuous coordination throughout implementation, and meeting challenges during both planning and implementation. As other environmental projects in the bay produce mixed results, projects which meet their goals for success need to be examined and potentially learned from. Incorporating pragmatism, cooperation, and issue management, as demonstrated in the 2014 oyster outcome, into future oyster restoration projects and broader environmental efforts in the Chesapeake Bay could offer increased potential to meet environmental goals
Structures and interactions of the enteroviral replication platform
No full textThe Enterovirus genus includes RNA viruses responsible for several human diseases, such as the common cold, poliomyelitis, acute flaccid paralysis, and myocarditis. These viruses contain conserved RNA structures at the extreme 5′ end of their genomes that recruit essential viral and host proteins, such as 3CD and PCBP2, to promote viral genome replication. This dissertation investigated the high-resolution structures of REPLRs from different humaninfecting enteroviral species and uncovered a conserved structural basis of enteroviral genome replication, illuminating promising opportunities to develop universal anti-enteroviral therapeutics targeting this platform. First, two crystal structures of the CVB3 REPLR were determined. In these crystals, the REPLR RNA folded into an antiparallel H-type four-way junction comprising four subdomains, sA, sB, sC and sD, with co-axially stacked sA-sD and sBsC helices and stabilized by a tertiary interaction between a conserved adenine within the sCloop and the sD-helix. Using NMR, mutagenesis, phylogenetic, and 3C and PCBP2 binding studies, this research also revealed that these crystal structures represent a conserved architecture of enteroviral REPLRs, including the sC-sD interactions and the H-shaped architecture provides a ready-made platform to recruit 3CD and PCBP2 for viral replication. Second, the crystal structures of the rhinoviruses B14 (RVB14) and rhinoviruses C15 (RVC15) REPLRs were determined. These structures revealed a highly conserved H-type fourway junction almost identical to the CVB3 REPLR, including the sC-sD long-range interactions. Such conserved features observed in the crystal structures also allowed us to predict the models of several other five enteroviral REPLRs using homology modeling. The structure-guided binding studies with full-length human PCBP2 showed that two previously proposed binding sites within REPLRs reside proximally and bind a single PCBP2 molecule. The DNA oligos complementary to the REPLRs abrogated their interactions with the PCBP2, illuminating promising prospects for developing therapeutics against enteroviral infections targeting this replication platform. Third, the structural basis of the enteroviral REPLR-3CD interactions was investigated using X-ray crystallography and other biophysical methods. 3CD is an enteroviral protein (fusion of 3C protease and 3D RNA-dependent RNA polymerase) required for viral RNA synthesis during replication. The crystal structures of both intact REPLR-3C and isolated sD-3C complexes were determined using CVB3 REPLR as a model system. These structures revealed that the sD stem-loop is the sole determinant for binding two 3C monomers, with each monomer recognizing the lateral surface of the sD helix. Binding studies with structure-guided REPLR and 3C mutants further clarified the roles of specific nucleotides and residues involved in the interactions between REPLR and 3C, explaining earlier virological observations. Comparative structural and binding studies of 3C, 3D, and 3CD with REPLRs from seven different enteroviral species further showed that while the 3D domain does not contribute to REPLR binding, the sD sequence and its structural pattern govern 3CD-REPLR interactions through the 3C domain. Although several more aspects of this RNA-based enteroviral genome replication need to be investigated, this research has set an initial foundation for pursuing structure-guided studies of enteroviral replication in vivo
What Made MCPS Magnet Programs Work?
No full textMontgomery County Public Schools is proposing to expand its magnet programs to build on a pedagogical method seen as highly successful over four decades, but faces criticism that their actual plans are unlikely to provide the necessary resources and support. Sunil Dasgupta asks former longtime coordinators of two of the most successful MCPS magnet programs, Eileen Steinkraus, at Montgomery Blair High School Math and Science magnet, and Mark Curran, at coordinator of the Poolesville High School, about what make those programs work and what it might take to replicate them. Music by Drew Pictures and the Lead Extras.https://open.spotify.com/episode/4C4Kjk7wxeTDfRceTaT5U
Sufficient conditions for strong discrete maximum principles in finite element solutions of linear and semilinear elliptic equations
No full textWe introduce a novel technique for proving global strong discrete maximum principles for finite element discretizations of linear and semilinear elliptic equations for cases when the common, matrix-based sufficient conditions are not satisfied. The basic argument consists of extending the strong form of discrete maximum principle from macroelements to the entire domain via a connectivity argument. The method is applied to discretizations of elliptic equations with certain pathological meshes, and to semilinear elliptic equations.http://arxiv.org/abs/2509.0093
Investigating recent decadal trends in the Pacific westerly jet in response to various atmospheric forcings using CMIP6 model results and reanalysis data
No full textThe strength and location of the North Pacific westerly jet (NPWJ) affects weather and trans-Pacific pollution transport as it triggers and directs atmospheric river events toward North America. We used four reanalysis datasets and eight Coupled Model Inter-comparison Project Phase 6 (CMIP6) models to investigate the characteristics and changes of the NPWJ during 1980-2019. The NPWJ climatologic core seasonally swings between north and south, being most southerward (~33° N) in winter and most northward (~45° N) in summer, as shown by the observation-based reanalysis data. All data provide strong evidence for the weakening (up to -0.45 and -0.68 ms⁻¹ decade⁻¹) and northward shift (0.2° and 1.0°) of the NPWJ in summer and autumn during the study period. Various atmospheric forcing experiments performed by the CMIP6 models further reveal aerosol forcing being the main driver, which can be traced back to the spatially inhomogeneous anthropogenic aerosol emission changes that increase in Asia and decrease in Europe. When we apply Earth system climate models to investigate the feedback between atmospheric forcings and atmospheric dynamical fields on decadal scales, two points should be noted. First, there is a need to include interactive chemistry in the CMIP6 model simulations to bring the dynamical fields closer to those based on observational data. Second, in addition to the well-mixed greenhouse gases, anthropogenic aerosols, and natural forcings proposed in the Detection and Attribution Model Intercomparison Project (DAMIP) single-forcing simulations, time-varying ozone radiative forcing is also important to climate change.The authors thank the four institutional centers (ERA5, JRA55, MERRA2, and NCEP) for providing long-term reanalysis data, as well as the eight modeling groups (BCC-CSM2-MR, CanESM5, CNRM-CM6-1, GISS-E2-1-G, HadGEM3-GC31-LL, IPSL-CM6A-LR, MIROC6, and MRI-ESM2-0) who contributed to the CMIP6 multi-model intercomparison. This research was funded by the NASA Atmospheric Composition Modeling and Analysis Program (ACMAP 80NSSC23K1000). Computational resources supporting this research were provided by the NASA GMAO SI Team and the High-End Computing (HEC) Program at the NASA Center for Climate Simulation (NCCS) at Goddard Space Flight Center (GSFC).https://egusphere.copernicus.org/preprints/2025/egusphere-2025-4501
Determining the taxonomic and functional profile of marine bacterial copper systems involved in marine early copper surface colonization
No full textCopper-based antimicrobial paints are frequently used to inhibit the biofouling of marine vessels. However, some bacterial species can overcome this copper challenge and colonize the surfaces. The early adherent bacterial population of marine vessels plays an important role because of its ability to produce extracellular polymeric substances (EPSs), forming a thin layer of organic matter that traps nutrients from the water and protects other colonizers by blocking the toxic antifouling (AF) coatings. It is of interest to study the factors that drive the initial colonization of copper surfaces. We used a metagenomic sequencing approach to analyze the microbial diversity and potential functional abilities of early biofilm communities on copper surfaces and discovered enriched copper-specific functional traits in early colonizers compared to the bacterial community of the surrounding seawater. The functional analysis of early biofilm colonizers on copper surfaces in marine coastal environments provides insights into molecular mechanisms that support biofilm formation on copper surfaces. The taxa associated with copper resistance traits were found to dominate initial microbial communities on copper surfaces, allowing these organisms to survive on copper surfaces despite copper toxicity. Our analysis reveals the dominance of the genera Allomuricauda and Ruegeria, carrying several copper resistance genes, as the early colonizers of copper surfaces.The author(s) declare financial support was received for the research and/or publication of this article. This work was supported by UMBC internal funding. Portions of this work were funded through the U.S. Naval Research Laboratories under its base funds to the Nanoscience Institute, but the paper does not represent the U.S. Navy, the Office of Naval Research, or the U.S. Government.https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2025.1661535/ful
Eclipsing Stellar Flare on the Demon Star Algol Binary System Observed during the MAXI-NICER Follow-up Campaign in 2018
No full textAlgol is a well-known eclipsing binary hosting an active and variable star that exhibits frequent stellar flares. Here, we report our pre-planned and coordinated rapid X-ray follow-up observations of an eclipsing flare on Algol. The Monitor of All-sky X-ray Image (MAXI) detected a flare on Algol at 05:52 UT on 2018 July 4. Subsequently, we carried out a prompt X-ray monitoring with the Neutron star Interior Composition Explorer (NICER) starting at 19:45 UT on the same day, and the observation ended at 06:02 UT on 2018 July 6. During the decaying phase of the flare, we successfully detected a 5.8-hour-long eclipse, corresponding to the secondary eclipse in which Algol A blocks the line of sight to Algol B. During the eclipse, the 2–10 keV X-ray flux is decreased to 20% level from 1.9 × 10⁻¹⁰ erg cm⁻² s⁻¹ to 4.5 × 10⁻¹¹ erg cm⁻² s⁻¹ . We found a configuration of the flare size and location to explain the X-ray observations; e.g., the flare occurred at the latitude 45°S of the Algol B surface with a flare height of 1.9 × 10¹¹ cm, corresponding to 0.8 times the stellar radius of Algol B, giving 80% obscuration of the flare loop by Algol A. The apparent absorption increase before the eclipse might originate from coronal mass ejection (CME) in the line of sight ejected during the flare.We sincerely thank Dr. Jerzy M Kreiner of Mt. Suhora Astronomical Observatory for kindly providing the O-C data (Kreiner 2004) of Algol used in this study. Some/all of the data presented in this article were obtained from the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute. The specific observations analyzed can be accessed via doi: 10.17909/5dyy-t366. The NICER analysis software and data calibration were provided by the NASA NICER mission and the Astrophysics Explorers Program. This research has made use of the MAXI data provided by RIKEN, JAXA and the MAXI team. W.I was supported by JSPS KAKENHI JP24K00673. T.E. was supported by the JST, Japan grant number JPMJFR202O (Sohatsu). Y.N. acknowledges the support from the NASA ADAP award program Number 80NSSC21K0632, the NASA TESS Cycle 6 Program 80NSSC24K0493, and the NASA NICER Cycle 6 Program 80NSSC24K1194. The work of K.H. is supported by NASA under award number 80GSFC24M0006.http://arxiv.org/abs/2510.1458
Meeting report: CEPI workshop on Rift Valley fever epidemiology and modeling to inform human vaccine development, Nairobi, 4–5 June 2024
No full textCoalition for Epidemic Preparedness Innovations (CEPI) two-day workshop in Nairobi, Kenya, 4–5 June 2024Rift Valley fever (RVF) is a zoonotic viral disease that causes epidemics and epizootics among humans and livestock, resulting in substantial health and socioeconomic consequences. Currently, there are no RVF vaccines licensed for humans, but several candidates show promise in early-stage development. Existing gaps in RVF epidemiological data and challenges associated with predicting RVF outbreak risk complicate the planning of efficacy studies, making the pathway to licensure for promising candidates unclear. In June 2024, the Coalition for Epidemic Preparedness Innovations (CEPI) convened a two-day workshop in Nairobi, Kenya, to discuss RVF epidemiology, modeling priorities, and specific gaps relevant to human RVF vaccine development. The workshop included representatives from multiple RVF-endemic countries, key global collaborators, and international health organizations. Workshop participants identified five key priorities: (1) Looking beyond outbreaks: There is a need to better characterize the complex One Health epidemiology of RVF and understand interepidemic persistence of the virus; (2) Better data for better models: Epidemiological modeling is crucial for research, prediction, and planning, but it requires accurate and representative data; (3) New, improved and accessible diagnostics and serological assays: These are needed to inform epidemiology and case definitions, without which RVF research will continue to suffer due to paucity of data and challenges in determining infection and exposure; (4) Defining use cases, regulatory pathways, and implementation strategies for human vaccines: Clarity on these topics will facilitate licensure and effective use of RVF vaccines; and (5) People-centered approaches: Community engagement and involvement of social and behavioral scientists are key to the success of human vaccine research and development and implementation, particularly as the virus impacts livestock and livelihoods. Workshop participants welcomed a renewed focus for RVF epidemiology and modeling, and expressed enthusiasm for continued multidisciplinary collaborations to support enabling sciences for human RVF vaccine research and development.This workshop was funded by the Coalition for Epidemic Preparedness Innovations (CEPI)https://www.sciencedirect.com/science/article/pii/S0264410X2500157
Religious Minority Youth’s Civic Engagement: A Focus on the Role of Parenting and Social Identity
No full textThis dissertation examined the complex and culturally grounded mechanisms that support civic development among Muslim American youth, with a focus on parental socialization, religiosity, and identity. Across three studies, this work adopted a strength-based, developmental approach to highlight how family and cultural contexts can foster positive youth outcomes in a socio-political climate marked by marginalization. Paper 1 explored the mediating role of multiple dimensions of religiosity, religious attitudes, practices, and struggles, in the association between maternal promotion of volitional functioning and adolescents’ civic engagement. Using data from 221 Muslim American adolescents (ages 13–18 years; Mage = 16.4), results indicated that maternal support for autonomy was positively linked to adolescents’ civic engagement through their engagement in religious practices, suggesting that autonomous religious internalization can serve as a foundation for civic responsibility. Paper 2 investigates how maternal religious and civic socialization practices predict emerging adults’ civic engagement through their religious identity. Among 329 Muslim American emerging adults (Mage = 21.4 years), path analyses revealed that maternal religious socialization promoted emerging adults’ civic behavior indirectly through their religious identity private regard, while maternal civic socialization was directly associated with emerging adults ' civic attitudes. These findings underscore the distinct yet complementary roles of culturally rooted and civically focused parenting in shaping youth’s civic attitudes and behaviors. Paper 3 employed a person-centered approach (Latent Profile Analysis) with longitudinal data to identify distinct profiles of Muslim American youth (n = 168; Mage = 21.4 years) based on maternal socialization practices and youth identity dimensions. Results revealed nuanced combinations of socialization and identity configurations associated with divergent youth civic outcomes one year later. Importantly, profiles with high maternal socialization but low American identity were associated with higher critical action, while profiles with bicultural identity and moderate socialization demonstrated lower political engagement, suggesting that youth civic actions are shaped by the intersection of socialization exposure and identity salience. Furthermore, youth who receive less maternal religious and civic socialization messages reported being less civically engaged compared to other profiles. Together, these three papers advance developmental theory by highlighting the dynamic interplay between parenting, religiosity, identity, and civic engagement within a marginalized cultural context. The findings offer actionable insights for educators, policymakers, and community-based programs seeking to promote inclusive civic development among Muslim American youth.
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