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Thermo-reversible gelation of self-assembled conducting polymer colloids
No full textThis article was originally published in Nature Communications. The version of record is available at: https://doi.org/10.1038/s41467-025-66034-x\
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© The Author(s) 2025Electrically conductive hydrogels based on conducting polymers have found increased use in bioelectronics due to their low moduli that mimic biological tissues, their ability to transport both ionic and electronic charges, and their ease of processing in various form factors via printing or injection. Current approaches towards conductive hydrogels, however, rely on covalent and therefore irreversible crosslinking mechanisms. Here, we report a thermo-responsive conducting polymer (TR-CP) that undergoes a fully reversible non-covalent crosslinking at 35 °C within less than a minute to form conductive hydrogels. The TR-CP is based on a block polyelectrolyte complex, that self-assembles into well-defined colloidal particles in water which undergo an isovolumetric sol-gel transition just below physiological temperature. The hydrogels have tunable mechanical properties in the 20 to 200 Pa range, are stable at various pH and salt conditions, self-healing, injectable, and biocompatible in vitro and in vivo. We demonstrate that the TR-CPs can be used to fabricate sensitive, conformal and reusable electrodes for surface electromyography. This thermo-responsive material provides exciting opportunities for stimuli-responsive and adaptive bioelectronics.This work was supported by a National Science Foundation (NSF) CAREER award (grant No. DMR-2237888) (synthesis and characterization), a Beckman Young Investigator award from the Arnold and Mabel Beckman Foundation (dx.doi.org/10.13039/100000997) (processing and applications), and a University of Delaware Research Foundation (UDRF) seed funding to L.V.K. X.X., and J.R. acknowledge support from the Army Research Office under Cooperative Agreement Number W911NF-23-2-0138. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Office or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes, notwithstanding any copyright notation herein. R.D. and J.R. acknowledge support from NIH grant 5T32EB031527-04. K.S. acknowledges funding support from National Institute of Standards and Technology (NIST), Department of Commerce under agreement #370NANB17H302. W.X. and D.P. acknowledge support by NSF through the University of Delaware Materials Research Science and Engineering Center (MRSEC) (DMR-2011824). M.G. and E.D.G. acknowledge support from NSF under Award DMR-1905550. C.L.C. acknowledges support from NIH grant 5T32HL094293-14. The use of facilities and instrumentation at the University of Delaware was supported by the National Institutes of Health (NIH), NSF awards CHE-0421224 (NMR), and CHE-1428149 (XPS). SAXS experiments (W. X.) were performed at the LiX beamline of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. The LiX beamline is part of the Center for BioMolecular Structure (CBMS) which is primarily supported by the NIH NIGMS through a Center Core P30 Grant (P30GM133893), and by the DOE Office of Biological and Environmental Research (KP1607011). K. O. acknowledges support from the University of Delaware Startup funds. The authors would like to thank Prof. Norman Wagner for access to the AR-G2 rheometer, Prof. Emil Hernandez-Pagan for access to the in-situ Raman spectrometer, and Prof. David Martin for access to electronic characterization equipment. We acknowledge Dr. Sung Hyun (Joseph) Cho’s assistance with cryo-EM data acquisition and the cryo-EM facility available in Huck Institutes of the Life Sciences at Penn State University. We would also like to thank Tulika Bhattacharya for her help in conducting rheology experiments, and Yaping Wang and Yong Zhao for their help in collecting preliminary data for TEM and cryo-EM. National Science Foundation, DMR-2237888: L.V.K. Beckman Young Investigator award: dx.doi.org/10.13039/100000997: L.V.K. University of Delaware Research Foundation: L.V.K. Army Research Office W911NF-23-2-0138: X.X. and J.R. National Institutes of Health: 5T32EB031527-04: R.D. and J. R. National Institute of Standards and Technology (NIST), Department of Commerce #370NANB17H302: K.S. University of Delaware Materials Research Science and Engineering Center (MRSEC) (DMR-2011824): W.X. and D.P. National Science Foundation, DMR-1905550: M.G., E.D.G. National Institutes of Health 5T32HL094293-14: C.L.C. National Institutes of Health (NIH), NSF awards CHE-0421224 (NMR), and CHE-1428149 (XPS): V.S.D., C.L., J.A.A. N.Y., T.S., and L.V.K
The relationship between home sound environment, sustained attention skills, and auditory cortex maturation in infants
No full textMorini, GiovannaThe purpose of this study was to investigate the relationship between household noise and development of early cognitive skills, as well as auditory cortex development – both of which are critical for early language development. Noise exposure affects important processes for cognition (e.g., sustained attention) and general learning. Evidence suggests that exposure to noise may disrupt the emergence of sound representations in the brain, which are needed to process auditory information (especially spoken language). The current project posed two interrelated questions: (i) What is the effect of noise exposure on real time measures of cognitive performance during infancy? and (ii) What is the effect of noise exposure on real time measures of auditory cortex function during infancy? Data were collected as part of a larger study. The current project combined naturalistic, behavioral, and neural measures. Seventeen infants completed a cognitive task, a cortical task, and an at-home sound environment measure at 8-10 months of age, in addition to caregiver reports regarding auditory development and noise exposure. Nine infants participated in the same study procedures at 17-19 months of age. Findings suggest that noise exposure and auditory development may impact performance during the cognitive task, and provide avenues for future research. Improving our understanding of the impact of noise on infant cognitive and cortical development may inform interventions within the household, childcare settings, and in public policy. This work may have implications for parental and childcare interventions, cognitive and cortical developmental research, and the understanding of noise exposure impact.University of Delaware, Department of Psychological and Brain SciencesM.S
Physical Activity in Pre-Ambulatory Children with Cerebral Palsy: An Exploratory Validation Study to Distinguish Active vs. Sedentary Time Using Wearable Sensors
No full textThis article was originally published in Sensors. The version of record is available at: https://doi.org/10.3390/s25041261.
© 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Wearable inertial sensor technology affords opportunities to record the physical activity of young children in their natural environments. The interpretation of these data, however, requires validation. The purpose of this study was to develop and establish the criterion validity of a method of quantifying active and sedentary physical activity using an inertial sensor for pre-ambulatory children with cerebral palsy. Ten participants were video recorded during 30 min physical therapy sessions that encouraged gross motor play activities, and the video recording was behaviorally coded to identify active and sedentary time. A receiver operating characteristic curve identified the optimal threshold to maximize true positive and minimize false positive active time for eight participants in the development dataset. The threshold was 0.417 m/s2 and was then validated with the remaining two participants; the percent of true positives and true negatives was 92.2 and 89.7%, respectively. We conclude that there is potential for raw sensor data to be used to quantify active and sedentary time in pre-ambulatory children with physical disability, and raw acceleration data may be more generalizable than the sensor-specific activity counts commonly reported in the literature.This research was funded by the National Institute on Disability, Independent Living, and Rehabilitation Research, Field-Initiated Research Grant H133G140166 (Prosser), National Institute of Child Health and Human Development award 1R01HD098364 (Prosser (contact), Kolobe, Smith), and the UNIDEL Distinguished Graduate Fellowship (Orlando)
Whose Geography, Whose History? Reimagining How We Teach the History of Geography
No full textThis article was originally published in The Professional Geographer. The version of record is available at: https://doi.org/10.1080/00330124.2025.2549768
This is an Accepted Manuscript version of the following article, accepted for publication in The Professional Geographer.
Kinkaid, E., Craig, B., Noble-Varney, R., Last, A., Ashutosh, I., Ehrkamp, P., … Wilson, M. (2025). Whose Geography, Whose History? Reimagining How We Teach the History of Geography. The Professional Geographer, 1–12. https://doi.org/10.1080/00330124.2025.2549768
It is deposited under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited.
This article will be embargoed until September 11, 2026What is the purpose of teaching the history of geography? To what end do we – or should we – tell stories of the discipline?
In this Roundtable, we join ongoing dialogues reflecting on the purpose and politics of teaching the history of geography (Kinkaid and Fritzsche 2022, Keighren et al. 2017, Cox 2006). As a group of faculty and students in the US, Canada, and Britain, we ask: How can we teach the history of geography within Anglo-American institutions in a present shaped by climate and environmental crisis; war and genocide; ongoing settler colonialism, imperialism, and militarism; contestations over borders, boundaries, and public space; and the ongoing exclusions and violence of our discipline’s spaces and histories?
To answer these questions, we approach History of Geographic Thought courses as a site of disciplinary reproduction (Kinkaid and Fritzsche 2022, Mayhew 2015) in which “the canon,” our professional identities, and our epistemologies and pedagogies are reproduced and potentially contested. In problematizing the “history of geography” enacted in these courses, we reflect on how a rather expansive and diverse intellectual history of geographic thought is selectively fashioned into disciplinary foundations and something of a canon (see Mayhew 2015 on debates about geography’s canon). In the process, history of geography courses can reproduce common exclusions and erase the diversity of geographic thought (see Kinkaid and Fritzsche 2022). Our goal in these commentaries is to propose ways in which the plural, polyvocal practice of geography that comprises the discipline’s actual history – which, for decades, has been shaped by strong currents of postcolonial, decolonial, feminist, Black, Indigenous, and queer thought and other perspectives outside of Anglo white male epistemologies – might become better aligned with “The History of Geographic Thought” as an intellectual, normative, and disciplinary formation we teach and situate ourselves within as scholars.
In each of the following commentaries, the contributors provide a “view from here” – grounding these concerns in their classrooms , subdisciplines, and geographic locations (in the US, UK, and Canada) and detailing how they have wrestled with geography’s legacies and attempted, in small ways, to rework them. In the conclusion, we reflect on the limitations of this dialogue and what is required to move it forward.
Reversible CO2 Hydrogenation, Neutron Crystallography, and Hydride Reactivity of a Triiridium Heptahydride Complex
No full textThis is the peer reviewed version of the following article: V. Cherepakhin, V. K. Do, A. J. Chavez, J. Kelber, R. A. Klein, E. Novak, Y. Cheng, X. Wang, C. M. Brown, T. J. Williams, Angew. Chem. Int. Ed. 2025, e202501943. https://doi.org/10.1002/anie.202501943, which has been published in final form at https://doi.org/10.1002/anie.202501943. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited.
© 2025 Wiley-VCH GmbH.
This article will be embargoed until 04/01/2026.The authors report the structure, reactivity, and catalytic utility of a triiridium complex, [Ir3H6(μ3-H)(PN)3]2+ (2-H, PN = (2-pyridyl)CH2PBut2). Despite its unusual stability to unsaturated organics, electrophiles, and even CF3SO3D, they find that complex 2-H catalyzes hydrogenation of CO2 to formate (TONIr = 9600) and reverse formic acid dehydrogenation (TONIr = 54 400). The hydrogenation operates via a reactive intermediate [Ir3H4(μ-H)4(PN)3]+ (5). Neutron crystallography and DFT-supported neutron vibrational spectroscopy of 2-H reveal Ir─H bond lengths and elucidate the vibration modes within the Ir3H7 core. Stoichiometric oxidation of 2-H produces four classes of iridium complexes of varied nuclearity and hydride structure: tetra- and pentanuclear clusters [Ir3H6(μ3-AuPPh3)(PN)3]2+ (2-Au) and [Ag{Ir2H4(μ-OAc)(PN)2}2]3+ (6) are generated using AuPPh3+ and AgOAc, respectively. Further oxidation to class [Ir2H3(μ-X)2(PN)2]+ is possible with AgOAc, Hg(OAc)2, or I2. Finally, a TEMPO/HCl system completely oxidizes the hydrides and gives [Ir2Cl4(μ-Cl)2(PN)2] (11).
Graphical Abstract available at: https://doi.org/10.1002/anie.202501943
A novel triiridium heptahydride cluster catalyzes reversible CO2 hydrogenation. Foundational structural and reactivity studies that combine neutron crystallography and spectroscopy, electrochemistry, synthetic studies, and kinetics uncover previously elusive metal–metal cooperative reactivity that enables a unique approach to functionalizing CO2.This work is sponsored by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (DE-EE-0011096). NIST contributed to performing this work. The authors thank the NSF (CHE-2018740, DBI-0821671, CHE-0840366), the NIH (S10 RR25432), and the USC Research and Innovation Instrumentation Awards for analytical equipment. Single-crystal neutron diffraction and vibrational spectroscopy measurements performed on TOPAZ and VISION beamlines used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory (ORNL). Computing resources were made available through the VirtuES and the ICE-MAN projects, funded by the Laboratory Directed Research and Development program and Compute and Data Environment for Science (CADES) at ORNL. X.W. acknowledges research sponsorship from the Laboratory Directed Research and Development Program at ORNL, managed by UT-Battelle, LLC, for the U.S. DOE. The authors are grateful to Dr. William Richards (USC), Juan Pablo De Los Rios (USC), and Dr. Thomas Saal (USC) for help with analytical equipment, and Dr. John Gordon (Brookhaven) for insightful discussions. Fellowship assistance from the Arnold and Mabel Beckman Foundation (A.J.C.) and NSF REU award CHE-1757942 (J.K.) is gratefully acknowledged. R.A.K. appreciates support from the U.S. DOE Office of Energy Efficiency and Renewable Energy (EERE), Hydrogen and Fuel Cell Technologies Office (contract no. DE-AC36-8GO28308) to the National Renewable Energy Laboratory (NREL). Certain commercial equipment, instruments, or materials are identified in this document. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the products identified are necessarily the best available for the purpose
Tellurite and selenite processing by tellurite resistant marine microbes
No full textThis article was originally published in Applied and Environmental Microbiology. The version of record is available at: https://doi.org/10.1128/aem.00881-25
Copyright © 2025 Ollivier et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license. https://creativecommons.org/licenses/by/4.0/Understanding microbial transformations of the group VIa/16 metalloids tellurium and selenium is important for the remediation of contaminated environments and has been proposed as a green route for Se/Te nanoparticle synthesis. We previously isolated several strains of aerobic tellurite resistant marine yeast and bacteria. Here, we explored the capability of these strains to metabolize selenite and mixtures of tellurite and selenite to quantify fate and identify volatile metabolic products. The experimental results indicate that selenite is metabolized differently than tellurite by the yeast Rhodotorula mucilaginosa and bacteria Bacillus spp. and Virgibacillus halodenitrificans. The production of volatile Se compounds appears to be positively correlated with selenite resistance. However, selenite fate, e.g., the proportion of volatilized or precipitated Se, was not predictable from tellurite resistance or fate of the same strain. Under non-aerated conditions, when cultures were provided mixtures of selenite and tellurite, tellurite strongly influenced the fate of selenite and the types of volatile products made. Tellurite in oxyanion mixtures appears to strongly inhibit Se volatilization and drive speciation to less complex Se volatiles. Mixtures boosted the production of Te and Se precipitates by Bacillus sp. strain 6A and the production of Te precipitates by Rhodotorula mucilaginosa strains 13B and decreased the production of both volatile Te and Se compounds. Dimethylselenide and dimethyltelluride are acutely toxic by inhalation and oral exposure, so understanding their production is a key consideration in any biologically based manufacture of Se/Te containing nanoparticles
AUTOMATIC ANALYSIS OF TIMING AND SYNCHRONY IN ROWING
No full textenterSynchrony and Timing are key components of the sport of rowing. This thesis
investigated different ways of determining the synchrony between two athletes on
rowing ergometers in a video. First, human pose estimation techniques were used to
extract body key points and compare the synchrony of one or multiple body parts across
the length of the video. Second, a video classification model based on either the R3D or
I3D model were trained to classify rowing videos as synchronized or unsynchronized
and their performance was compared.
The pose estimation approach could detect and highlight small asynchronies
between rowers that are hard to detect for humans and could provide valuable additions
to rowing training. For the video classification approaches, the R3D-based model
reliably classified rowing videos and generalized well to unseen and slightly different
data. It outperformed the I3D-based approach, which performed well on the training
data but generalized poorly to different data.ente
Racialized bias in pediatric pain: the role of observers’ attentional processing and estimations of children’s pain
No full textThis article was originally published in [Journal Name]. The version of record is available at: https://doi.org/10.7717/peerj.19969
©Copyright 2025 Kissi et al. Distributed under Creative Commons CC-BY 4.0Background: Research demonstrates racism in pediatric pain care. However, the
mechanisms underlying these injustices are not well understood. This study
examined White observers’ attentional processing of facial expressions of pain
demonstrated by White vs. Black children and observers’ estimations of the pain
expressiveness levels of these children. Furthermore, we assessed whether differences
in observers’ attentional processing were influenced by observers’ pain beliefs and the
pain expressiveness level.
Method: Eighty White adults (42 women; 38 men) performed the visual search task
(VST), rated the levels of pain that the children expressed, and reported their beliefs
concerning the pain experience of White vs. Black children.
Results: Findings revealed facilitated attentional engagement towards Black
compared to White child pain faces, particularly at high pain expressiveness levels.
No attentional disengagement effects were observed. Pain estimations increased with
increasing pain expressiveness but, contrary to prior findings, did not differ for
White vs. Black children. Observers’ false pain beliefs did not significantly impact
their attentional processing nor pain estimations.
Conclusions: The results underscore the importance of understanding how
racialized disparities in observers’ attentional processing of others’ pain may
contribute to racialized inequities in pediatric pain careThis work was supported by a FWO Grant (Research Foundation Flanders, n G023423N)
awarded to Tine Vervoort, Dimitri Van Ryckeghem & Adam Hirsh. The funders had no
role in study design, data collection and analysis, decision to publish, or preparation of the
manuscript
Measurement of Atmospheric Neutrino Oscillation Parameters Using Convolutional Neural Networks with 9.3 Years of Data in IceCube DeepCore
No full textPlease see publication for complete list of co-authors. This article was originally published in Physical Review Letters. The version of record is available at: https://doi.org/10.1103/PhysRevLett.134.091801.
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license (https://creativecommons.org/licenses/by/4.0/). Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP 3.
.The DeepCore subdetector of the IceCube Neutrino Observatory provides access to neutrinos with energies above approximately 5 GeV. Data taken between 2012 and 2021 (3387 days) are utilized for an atmospheric disappearance analysis that studied 150 257 neutrino-candidate events with reconstructed energies between 5 and 100 GeV. An advanced reconstruction based on a convolutional neural network is applied, providing increased signal efficiency and background suppression, resulting in a measurement with both significantly increased statistics compared to previous DeepCore oscillation results and high neutrino purity. For the normal neutrino mass ordering, the atmospheric neutrino oscillation parameters and their 1 errors are measured to be Δm2 32=2.40+0.05−0.04×10−3 eV2 and sin223=0.54+0.04−0.03. The results are the most precise to date using atmospheric neutrinos, and are compatible with measurements from other neutrino detectors including long-baseline accelerator experiments.The authors gratefully acknowledge the support from the following agencies and institutions: (USA) U.S. National Science Foundation-Office of Polar Programs, U.S. National Science Foundation-Physics Division, U.S. National Science Foundation-EPSCoR, U.S. National Science Foundation-Office of Advanced Cyberinfrastructure, U.S. National Science Foundation AI Institute for Artificial Intelligence and Fundamental Interactions, Wisconsin Alumni Research Foundation, Center for High Throughput Computing at the University of Wisconsin–Madison, Open Science Grid, Partnership to Advance Throughput Computing, Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support, Frontera computing project at the Texas Advanced Computing Center, U.S. Department of Energy National Energy Research Scientific Computing Center, Particle astrophysics research computing center at the University of Maryland, Institute for Cyber-Enabled Research at Michigan State University, Astroparticle physics computational facility at Marquette University, NVIDIA Corporation, and Google Cloud Platform; (Belgium) Funds for Scientific Research (FRS-FNRS and FWO), FWO Odysseus and Big Science programs, and Belgian Federal Science Policy Office; (Germany) Bundesministerium für Bildung und Forschung, Deutsche Forschungsgemeinschaft, Helmholtz Alliance for Astroparticle Physics, Initiative and Networking Fund of the Helmholtz Association, Deutsches Elektronen Synchrotron, and High Performance Computing cluster of the RWTH Aachen; (Sweden) Swedish Research Council, Swedish Polar Research Secretariat, Swedish National Infrastructure for Computing, and Knut and Alice Wallenberg Foundation; (European Union) EGI Advanced Computing for research; (Australia) Australian Research Council; (Canada) Natural Sciences and Engineering Research Council of Canada, Calcul Québec, Compute Ontario, Canada Foundation for Innovation, WestGrid, and Digital Research Alliance of Canada; (Denmark) Villum Fonden, Carlsberg Foundation, and European Commission; (New Zealand) Marsden Fund; (Japan) Japan Society for Promotion of Science and Institute for Global Prominent Research of Chiba University; (Korea) National Research Foundation of Korea; (Switzerland) Swiss National Science Foundation
Black Insurgency: the long struggle for land and national independence
No full textHicks, Cheryl D.The goal of Black Insurgency is to intervene in the classical period of Black Power Studies to produce scholarship that argues the perspectives of understudied organizations and activists who were not interested in reshaping American democracy, but rather sought to dismantle U.S. imperialism, colonialism, and white supremacy, in-favor of Black self-determination. Land is the paradigm through which Black Insurgency examines a protracted struggle against domestic colonialism by Black radical organizations. Political violence by these organizations was the mechanism by which an overturning of the colonial order could manifest Black self-determination. Violence against the state was characterized as revolutionary action, necessary to topple the United States as a colonial regime that had been oppressing African-Americans. Organizations like, the Revolutionary Action Movement (RAM), the Republic of New Afrika (RNA), and the Black Liberation Army (BLA), who embodied revolutionary Black nationalism, are either misunderstood or understudied within the field of Black Power Studies. Black Insurgency will intervene into the scholarship on Black Power to argue that not only was resistance as political violence an essential strategy for self-defense, but also a tactical response to the long-standing colonial war against Black America, while in pursuit of a Black nation-state. These revolutionary Black nationalist organizations and activists are ideologically similar in their approach to Black self-determination and demonstrate a central radical response within the Black Freedom Struggle that must be carefully engaged. The analysis of internal colonialism, Third World internationalism, armed struggle, land, and national independence are the politics of anti-imperialism by organizations that wish to dismantle U.S. imperialism internally, while simultaneously achieving national independence.University of Delaware, Department of Africana StudiesM.A