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PEACE AS JUSTIFICATION FOR WAR IN THE GESTA GUILLELMI OF WILLIAM OF POITIERS
No full textenterThis paper analyzes an eleventh-century biography of William the Conqueror,
the Gesta Guillelmi, written by William of Poitiers (WP), chaplain to the Norman
duke and English king. It particularly focuses on how the narrative of the biography
justifies the controversial career of the Conqueror in terms of peace and order;
ultimately, WP praises the Conqueror’s actions as divinely-inspired enforcement of
peace over unruly subjects. In this way, WP portrays his master as a pious and
virtuous king, concerned for the well-being of his people and determined to check the
disruption of sinful rebellion. The paper also discusses how the chaplain manipulates
historical details to mold such an image of William the Conqueror, as well as
speculating as to how the circumstances of the 1070s, when WP was writing, factor
into the meaning of the work as a whole. It argues that the Gesta functions as a work
of propaganda aiming to defend William from accusations of unkinglike behavior, to
celebrate his promotion to the status of king, and discourage current and potential
hostilities against the Norman king’s regime.ente
THE CERVETTI IN GEORGIAN LONDON: A STUDY OF CELLO PERFORMANCE, REPERTOIRE, AND THE SPREAD OF THE FORMA B STRADIVARIUS CELLO
No full textenterThe violoncello emerged in Italy in the mid-sixteenth century, gradually
spreading across Europe and fulfilling the role of an accompaniment instrument in
ensemble playing. By the middle of the seventeenth century, the instrument could be
found in England, though it had no solo repertoire designated for its performance.
With the arrival of Italian immigrants in the early eighteenth century, the cello began
its rise to prominence. Italian cellist Giacobbe Cervetto immigrated to London in the
1730s, and was a prominent performer and composer, writing solo pieces for the cello.
His son, James Cervetto, followed in his father’s footsteps, starting his career as a
child prodigy on the cello and becoming a well-known professional cellist by his
twenties.
The Cervetti were tied to several luthiers throughout their careers, including
Cremonese luthier Antonio Stradivari, British luthier William Forster Senior, and his
son, William Forster Junior. Their musical circle also included composers such as
Willem de Fesch, Karl Friedrich Abel, Johann Christian Bach, and Franz Joseph
Haydn. The performing careers of Giacobbe and James Cervetto also coincide with the
elevation of the cello from the confines of the continuo role to an instrument widely
regarded for its soloistic capability.
This thesis examines the Cervetto family and their circle, a study of the
individuals who shaped the advancements in construction and repertoire for the
violoncello throughout its development in the eighteenth century.ente
Floodplain storage and its influence on sediment transport: new insight from field and modeling studies
No full textPizzuto, James E.As sediment moves through a watershed, it cycles between periods of channelized transport and immobile storage in adjacent reservoirs. Floodplains serve as the largest and longest-lived reservoir in many river systems, storing sediment for years to millennia before remobilization. This dissertation investigates how floodplain storage influences sediment transport across space and time through a combination of field and numerical modeling studies. ☐ A field-based study of the Powder River in Montana quantifies the duration of storage and remobilization using a new methodology to reconstruct the age distribution of eroded material. Results indicate an exponential storage time distribution with a mean of ~800 years, suggesting sediment delivery is governed by meander belt reworking in laterally confined valleys. ☐ A numerical sediment routing model is then developed to simulate channel floodplain sediment exchange while tracking the age of stored sediment. The model tests both age-independent and age-dependent erosion functions. Results show that age-dependent erosion, where younger sediment is preferentially eroded, increases sediment delivery timescales. Model results are consistent with analytical solutions and reveal the importance of age structure in floodplain storage. ☐ The previous model is restricted to a single river valley with constant width and channel morphology. In the final chapter, these restrictions are addressed, and a model is developed to route sediment through a network of river valleys with spatially variable floodplain width, water discharge, and tributary sediment supply. This expanded framework is used to simulate a branched watershed network based on the White Clay Creek in southeastern Pennsylvania. This network model successfully reproduces sediment fluxes compared to sediment budget data and is used to test idealized restoration scenarios within a watershed network. Reducing upstream sediment input or limiting floodplain erosion produced only modest decreases in suspended sediment flux reaching the watershed outlet, indicating that common restoration practices may have limited effects. However, further validation of this is needed before it should be used to evaluate specific restoration scenarios. ☐ Together, these studies highlight the impact that floodplain sediment storage and remobilization have on sediment delivery timescales, as well as offering new tools for evaluating restoration strategies in sediment-impaired watersheds.University of Delaware, Department of Earth SciencesPh.D
The Taitao Ophiolite: Snapshot of Nascent Oceanic Mantle Emplaced Via Ridge-Trench Collision
No full text© The Author(s) 2025. Published by Oxford University Press. All rights reserved. For 23 permissions, please e-mail: [email protected].
This article was originally published in Journal of Petrology. The version of record is available at: https://doi.org/10.1093/petrology/egaf092
This article is embargoed until October 23, 2026The Taitao ophiolite is a sliver of oceanic lithosphere that formed at the Chile ridge at ~6 Ma and was emplaced shortly afterwards onto the Chilean continental margin during a ridge-trench collision. Located southeast of the modern-day Chile Triple Junction, the ophiolite provides a unique window into the mantle beneath an intermediate-spreading ridge axis, from which few peridotites have been recovered globally. We analyzed the compositions of harzburgites, plagioclase harzburgites, and clinopyroxenites from the mantle section of the Taitao ophiolite to investigate the history of partial melting, melt addition, and thermal evolution. Most Taitao harzburgites have spinel major element and clinopyroxene rare earth element contents that are consistent with residues after 12–15% melting of a depleted MORB mantle source. The compositional modifications due to melt addition are generally limited and spatially confined to plagioclase harzburgites near gabbroic intrusions and clinopyroxenites associated with dunites.
To constrain the thermal history of the Taitao ophiolite from formation at the Chile ridge to emplacement at the Chilean continental margin, we calculated closure temperatures by applying pyroxene- and olivine-based geothermometry to the Taitao peridotites. We compare these results with models for closure temperature as a function of initial temperature and cooling rate. Our results suggest that the Taitao peridotites underwent faster cooling (1–10°C/yr) than ophiolites globally, most of which cooled with rates <1°C/yr. This agrees with our calculation that the peridotites remained at high temperature for a relatively short time (<0.5 My) based on timescale estimates of emplacement using a ridge thermal model and mineral diffusive re-equilibration. Our rapid cooling rates for the Taitao peridotites exceed predictions from conductive cooling models, even those that account for hydrothermal effects, indicating the involvement of additional mechanisms. We interpret the fast cooling to result from ridge-trench collision and rapid obduction. This tectonic configuration juxtaposed hot sub-ridge mantle against a cold continental margin, leading to a significant temperature contrast and, therefore, faster average cooling rates during ophiolite emplacement. Other ophiolitic peridotites, in contrast, typically remain part of the oceanic lithosphere for longer and experience prolonged conductive cooling prior to obduction, resulting in slower cooling rates. Altogether, our results demonstrate that the Taitao ophiolite is an ideal archive for studying tectonic processes at intermediate-spreading ridges and during ridge-trench collision
Atmospheric refraction as a tool for stellar flare science in the Rubin LSST era
No full textBianco, FedericaI have developed and demonstrated a novel method to study stellar flare temperatures in the era of large, ground-based astronomical surveys by taking advantage of Differential Chromatic Refraction (DCR). This effect manifests as an apparent, color-dependent shift in source position towards the zenith of an observer, and must be corrected for in order to ensure accurate astrometric solutions. Despite this, multiple studies have shown how DCR can be employed as a tool to extract additional color information from source astrometry, and this work applies this method to stellar flares for the first time. Flares are particularly well suited to this technique due to their heightened frequency on M dwarfs, stars less massive than the Sun that make up the majority of stars in our galaxy. Due to their ubiquity across various regions of the sky, and the dramatic contrast between the red photosphere and blue flare emission, flares on M dwarfs offer an ideal opportunity to use DCR to infer effective flare temperatures across the unprecedentedly large sample of flares that will be detected in next-generation astronomical surveys, such as the Legacy Survey of Space and Time (LSST) that will be carried out by the Vera C. Rubin Observatory, starting in 2025. By combining Rubin's high image quality and astrometric precision with the truly massive amount of data it will produce over 10 years, DCR can be used to carry out a population-level statistical analysis of stellar flare temperatures. We additionally validated this technique on flare data obtained from an LSST precursor survey called the Deeper, Wider, Faster Programme, and showed how certain choices made when modeling the spectral and geometric properties of the flare could lead to overestimating the true flare temperature. Finally, we describe the framework for a value-added catalog of stellar flares detected in the LSST alert stream and data releases.University of Delaware, Department of Physics and AstronomyPh.D
Deterioration envelopes for predicting concrete bridge deck deterioration due to chloride exposure
No full textHead, Monique H.While bridge decks serve as the primary interface between vehicular loads and the underlying structural system, they are particularly susceptible to deterioration caused by environmental factors—most notably, chloride ingress from deicing salts, freeze-thaw cycles driven by temperature fluctuations, and repeated wetting and drying events due to precipitation and other water-related exposure to the base concrete material. Existing concrete deterioration models often fall short in capturing and predicting the effects of chloride exposure over time due to these evolving conditions, frequently treating concrete as a static material. This study, rather, focuses on the development of a revised, data-driven modeling approach that more accurately predicts the decrease in compressive strength and long-term material integrity based on extensive laboratory testing of concrete cylinder specimens and bridge deck cores extracted from bridges in Delaware. ☐ The overarching objective is to strengthen the predictive accuracy of deterioration models from experimental and in-situ data to better predict deterioration rates. The research draws upon three primary data sources that were generated: (1) controlled, accelerated laboratory testing, (2) core samples extracted from operational Delaware bridges provided by the Delaware Department of Transportation (DelDOT), and (3) climate-sensitive predictive modeling techniques through data collection from the National Oceanic and Atmospheric Administration (NOAA) and Federal Highway Administration (FHWA) InfoBridge™ database. Laboratory samples (n=300) were fabricated using mix designs representative of Delaware bridge construction practices from the 1970s and 1980s and testing using protocols from ASTM and ACI standards. These specimens were subjected to environmental conditioning protocols—including wet-dry and freeze-thaw cycling—at three levels of chloride concentration (low, medium, and high corresponding to 0, 3%, and 15% salt concentrations) to simulate field exposure from de-icing salts and sea spray. The laboratory specimens were designed to replicate multiple years of service-life deterioration within a condensed time frame, allowing for the observation of trends and prediction of long-term performance of degradation. Physical and mechanical parameters such as compressive strength, modulus of elasticity, resonance frequency, and chloride penetration. A comprehensive analysis of chloride-induced degradation mechanisms in concrete bridge decks was conducted to integrate the accelerated laboratory test results, in-situ field sampling, and historical inspection data to determine a representative durability index for new concrete deterioration envelopes that forecast the long-term response in terms of material degradation due to varying levels of chloride exposure. The experimental results reveal a gradual yet linear decline in both compressive strength and resonance frequency over time, accompanied by a corresponding increase in chloride content for up to 160 cycles, which corresponds to approximately 2-5 years. Resonance frequency emerged as the most sensitive and reliable indicator of internal concrete for damage, which showed a consistent decline across all chloride exposure conditions and served as a good predictor of material degradation. Overall, these findings emphasize the importance of combined in-situ and laboratory testing to better characterize material degradation of concrete that otherwise may not be fully captured by surface-based, visual bridge inspection methods alone.University of Delaware, Department of Civil, Construction and Environmental EngineeringM.C.E
Disclosing HIV status to sexual partner: Findings from a People Living with HIV Stigma Index 2.0 study in the country Georgia
No full textThis article was originally published in Plos ONE. The version of record is available at: https://doi.org/10.1371/journal.pone.0331919
© 2025 Zurashvili et al. This is an open access article distributed under the terms of the Creative Commons Attribution License https://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background
HIV status disclosure to sexual partner plays an important role in fostering transparency and reducing stigma, yet it remains a complex issue influenced by various sociodemographic, psychosocial, and experiential factors. This study investigated factors associated with HIV status disclosure to sexual partner among people living with HIV (PLHIV) in Georgia.
Methods
We conducted a secondary analysis of data from the PLHIV Stigma Index 2.0 study conducted in 2022–2023. Participants were recruited from HIV care centers and community-based organizations. Data collection utilized standardized questionnaires assessing sociodemographic factors, stigma, discrimination, and interactions with the healthcare system. Statistical analysis employed descriptive statistics, bivariate, and multivariate logistic regression to examine associations between stigma, sociodemographic factors, and status disclosure to sexual partner.
Results
Out of 765 participants, the mean age was 40.6 years, with a majority being male (67.4%). More than a fifth of respondents reported treatment interruptions, with 35.3% not disclosing their status to sexual partner. Disclosure was more common to close contacts than to others. Indicators of internalized stigma were common, with participants reporting feelings of guilt (40.1%), shame (36.1%), worthlessness (28.4%), and feeling ‘dirty’ (12.4%). Common behavioral reactions to stigma included avoiding medical visits (13.1%) and refraining from social support (10.5%). Over 40% did not disclose their status to sexual partner. Logistic regression highlighted that older age, knowing partner’s HIV status, positive disclosure experiences and enacted stigma were positively associated with status disclosure.
Conclusion
The complex dynamics between stigma and HIV status disclosure highlight the importance of providing decision support to PLHIV, helping them navigate disclosure process while considering potential risks and benefits. The findings emphasize the need for focused interventions that promote disclosure to sexual partner, especially among individuals with treatment interruptions, as it can significantly impact personal health and broader public health objectives, including the prevention of HIV transmission.The research reported in this publication was supported by the Fogarty International Center, of National Institute of Alcohol Abuse and Alcoholism of the National Institutes of Health under Award Number D43 TW011532 and K01DA053159. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
DIET-DEPENDENT EFFECTS OF DIGESTION ON METABOLIC RATE OF CLEARNOSE SKATES (Rostroraja eglanteria)
No full textenterThis study aimed to describe the impact of diet on specific dynamic action
(SDA) in Clearnose Skates (Rostroraja eglanteria). Metabolic rates of mature female
Clearnose Skates (n=2) were calculated before and after being fed anchovies and
shrimp. Metabolic rates were measured using static respirometry. Skates had an
increase of up to 1.68x pre-feeding MO2 when eating anchovy, and an increase of up
to 1.31x pre-feeding MO2 when eating shrimp. Meal size was also found to increase
the duration and peak of the SDA effect. Minimizing the amount of energy occupied
by SDA makes feeding more efficient and provides more available energy for
Clearnose Skates.ente
Intensification of Renewable 4,4′-Dimethylbiphenyl Synthesis for Recyclable Diesters
No full textThis document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Sustainable Chemistry and Engineering, copyright © 2025 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acssuschemeng.4c09233.
This article will be embargoed until 02/03/2026.Reducing the global dependence on petroleum-derived chemical products requires renewable alternatives to replace established materials. Recent investigations demonstrated a biobased pathway to prepare the platform chemical 4,4′-dimethylbiphenyl (4,4′-DMBP). The synthesis of 4,4′-DMBP follows a two-step process: (1) 2-methylfuran (2-MF) oxidative coupling to 5,5′-dimethyl-2,2′-bifuran (5,5′-DMBF) and (2) 5,5′-DMBF tandem Diels–Alder-dehydration with ethylene to afford 4,4′-DMBP. Here, we report the intensification of reaction conditions in step (1), improving 5,5′-DMBF space-time yield up to 1.10 mol L–1h–1, an 86% increase from the baseline. Scale-up of step (1) was hindered by oxygen-deprivation-induced palladium black formation and reaction exotherms decreasing yields at larger scales. Oxygen sparging, mechanical mixing, and internal cooling implemented simultaneously enabled a 108× increase in 5,5′-DMBF production to an average of 13 g/batch. In step (2), the use of a homogeneous La(OTf)3 catalyst in the Diels–Alder-dehydration reaction─instead of heterogeneous γ-Al2O3─led to a 54% increase in 4,4′-DMBP yield with a 70 °C temperature reduction to 180 °C. Scale-up of the Diels–Alder-dehydration to 3 g/batch maintained para-selectivity for 4,4′-DMBP with full conversion to the product within 20 h. Renewable 4,4′-DMBP is achieved from the improved pathway and isolated in 96.7% purity for further utilization downstream.The authors acknowledge the use of NMR facilities and instrumentation supported by the National Institute of General Medical Sciences under award number P20GM104316 from the National Institutes of Health and National Science Foundation Award CHE0421224
Resolving lipid-nanoparticle bleb structures from small angle scattering measurements
No full textWagner, Norman J.Lipid nanoparticles (LNPs) are delivery vehicles for nucleic acid payloads, such as siRNA and mRNA. Typical LNPs consist of the ionizable lipid, cholesterol, phospholipid, PEG-lipid, and nucleic acid, self-assembling into a nanostructure for biodistribution, endocytosis and endosomal escape necessary for RNA delivery and transfection. Recent studies report protruding structures on otherwise spherical LNPs, forming a two-compartment lipid-rich and aqueous-rich morphology termed LNP “blebs”. While Cryo-TEM measurements can identify bleb architectures, such measurements are limited in statistical sample size and require delicate sample preparation. Small-Angle Scattering (SAS) measurements of LNPs in formulation provide an alternative route to identify blebs, but existing analytical models are limited in resolving structural features. In this work, we present a computational workflow for efficient analysis of SAS experiments of LNP blebs to resolve their microstructure and composition. This workflow numerically calculates the pair distance distribution function (PDDF) for model LNP bleb structures via a simple Monte Carlo method, weights it by the product of excess scattering lengths based on the composition, and generates simulated SAS profiles by performing a 1D Fourier transform. ☐ A population-based evolutionary optimization algorithm, differential evolution (DE) is used to minimize the discrepancies between the simulated and experimental scattering profiles, refining structural parameters to reconstruct the representative morphology for the experimental sample. Recently published small-angle neutron scattering (SANS) experimental data of LNP-self-amplifying (SAM) RNA formulations (Thelen et al., ACS Nano, 2024) are analyzed. ☐ Simultaneous analysis of multiple SANS profiles measured under different solvent compositions enabled the quantification of average-size, structure and distribution of lipid components and RNA in the LNP bleb representative morphology for the formulations. Our computational workflow provides an efficient, automated, and physics-based approach for SAS analysis of complex morphologies and is shown to be an improvement over the prior, analytical approximations. The LNP model structure development and efficient calculation of PDDF shown in computational workflow is used for generating high-throughput data set of structure and PDDFs for a library of LNP morphologies. The data set developed is utilized in a separate work for developing Physics Informed Machine Learning model for LNP structure prediction. Additionally, a two-compartment core-shell bicelle analytical model is developed and tested as an approximate model for SAS analysis of LNP blebs which can be easily integrated with widely used SAS analysis software. The insights into the structure and composition of LNP blebs aid in the rational design of LNP formulations.University of Delaware, Department of Chemical and Biomolecular EngineeringM.Ch.E