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Constructivity conditions on immune sets
No full textThis article was originally published in Archive for Mathematical Logic]. The version of record is available at: https://doi.org/10.1007/s00153-024-00958-x
© The Author(s) 2025
This is an open access article distributed under the terms of the Creative Commons CC BY license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Definitionally: strongly effectively immune sets are infinite and their c.e. subsets have
maximums effectively bounded in their c.e. indices; whereas, for effectively immune
sets, their c.e. subsets’ cardinalities are what’re effectively bounded. This definitional
difference between these two kinds of sets is very nicely paralleled by the following
difference between their complements. McLaughlin: strongly effectively immune
sets cannot have immune complements; whereas, the main theorem herein: effectively
immune sets cannot have hyperimmune complements. Ullian: effectively immune sets
can have effectively immune complements. The main theorem improves Arslanov’s,
effectively hyperimmune sets cannot have effectively hyperimmune complements: the
improvement omits the second ‘effectively’. Two natural examples of strongly effectively
immune sets are presented with newcases of the first proved herein. The first is the
set of minimal-Blum-size programs for the partial computable functions; the second,
the set of Kolmogorov-random strings. A proved, natural example is presented of an
effectively dense simple, not strongly effectively simple set; its complement is a set of
maximal run-times. Further motivations for this study are presented. Kleene recursion
theorem proofs herein emphasize how to conceptualize them. Finally, is suggested,
future, related work—illustrated by a first, natural, strongly effectively 0
2 -immune set—included: solution of an open problem from Rogers’ book
Reward Hacking Mitigation using Verifiable Composite Rewards
No full textThis article was originally published in Proceedings of the 16th ACM International Conference on Bioinformatics, Computational Biology, and Health Informatics. The version of record is available at: https://doi.org/10.1145/3765612.3767230
This work is licensed under a Creative Commons Attribution 4.0 International License https://creativecommons.org/licenses/by/4.0/ BCB ’25, Philadelphia, PA, USA ©2025 Copyright held by the owner/author(s).Reinforcement Learning from Verifiable Rewards (RLVR) has recently shown that large language models (LLMs) can develop their own reasoning without direct supervision. However, applications in the medical domain, specifically for question answering, are susceptible to significant reward hacking during the reasoning phase. Our work addresses two primary forms of this behavior: i) providing a final answer without preceding reasoning, and ii) employing non-standard reasoning formats to exploit the reward mechanism. To mitigate these, we introduce a composite reward function with specific penalties for these behaviors. Our experiments show that utilizing RLVR with our proposed reward model leads to betterformatted reasoning with less reward hacking and good accuracy compared to the baselines. This approach marks a step toward reducing reward hacking and enhancing the reliability of models utilizing RLVR1.Our study was supported by NSF award 2443639, NIH awards, P20GM103446, and U54-GM104941. We also acknowledge computational credits from Amazon Web Services (AWS)
Bridging theory and practice in peer-to-peer energy trading: market mechanisms and technological innovations
No full textThis article was originally published in Environmental Research: Infrastructure and Sustainability. The version of record is available at: https://doi.org/10.1088/2634-4505/adac8a.
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license (https://creativecommons.org/licenses/by/4.0/). Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
© 2025 The Author(s). Published by IOP Publishing Ltd.The article provides a synthesis of the literature on the peer-to-peer (P2P) energy trading paradigm. P2P energy trading is a prosumer business model and a transformative concept that allows prosumers to sell surplus generation to other prosumers and consumers within an energy community or microgrid. P2P energy trading is a novel concept to promote decentralization, decarbonization, democratization, digitalization, and enhancing energy resilience of the energy sector. The article covers different facets of P2P energy trading, including market designs, changing actor roles, pricing mechanisms, enabling technologies, and challenges. The article thus addresses emerging and complementary aspects not covered in prior literature reviews. As such, three market designs are discussed: centralized, decentralized, and distributed, and four pricing mechanisms, which are optimization, game theory, auction-based, and reinforcement learning. Enabling technologies discussed are Energy Internet, Internet of Things, Artificial intelligence, Blockchain, Communication networks, and battery flexibility. The paper discusses the challenges that the development and commercialization of the P2P energy trading faces—especially focusing on the social ontology of the concept—and provides research directions to amplify the scaling up of the technology
Surface water quality patterns of White Clay Creek subwatersheds in Delaware and Pennsylvania
No full textKauffman, Gerald J.Changes in land use and land cover significantly impact surface water quality. Excess nutrients, chloride, and rising water temperatures from anthropogenic activity contribute to declining aquatic ecosystems, however, best management practices (BMPs) and restoration approaches allow us to mitigate these impacts. Ongoing monitoring is necessary to observe changes in water quality resulting from water quality improvement efforts and refine management approaches. This study examined water quality trends across monitoring sites within small-scale drainages in the White Clay Creek watershed and relationships with land cover, as well as recommendations for structural and non-structural BMPs based on results. Using simple linear regression and the nonparametric Mann Kendall test for monotonic trends, nutrients, chloride, and water temperature were examined with land and agricultural cover, seasons, and streamflow. Water temperature across all study sites exceeded the seasonal criteria for cold water fishes. Chloride concentrations remained, primarily, below the target level of 50.0 mg/L. Nitrate was found to remain consistently near or above the 3.0 mg/L TMDL target for total nitrogen at all sites, with five-year medians ranging from 3.2 mg/L to 10.0 mg/L, with the highest nitrate concentrations observed at East Branch sites. Orthophosphate concentrations were most frequently seen below the 0.2 mg/L TMDL target level for total phosphorus and were found to have significantly decreased throughout the study period. Weak correlations were present between several land cover types and water quality parameters, while weak to strong correlations were found among various farming types and annual median nitrate concentrations. Statistically significant relationships were seen between nitrate in surface waters and percent forest cover of the areas drained, and between nitrate and multiple farm types including percent mushroom, row crop, meadow, pasture (horse/cattle), and fallow cover. The percentage of mushroom farm cover and annual median nitrate concentrations within drainage areas displayed a very strong, positive correlation. Moderate, positive correlations were found among percent row crop cover and percent animal pasture with annual median nitrate concentrations across drainage areas. Further investigation is warranted in the White Clay Creek at East Branch sites exhibiting chronically poor nitrate concentrations and increased monitoring is needed to explore trends more thoroughly. These findings provide a foundation for recommendations or further research, and while this study is only focused on specific components of a larger issue, intervention at local levels is needed to contribute to the overall health of the watershed.M.S.University of Delaware, Water Science and Policy Progra
Sex differences in central neural activation during acute hypernatremia
No full textFarquhar, William B.Central salt sensing in the circumventricular organs (CVOs) is critical in regulating neurohormonal responses to acute relative hypernatremia as occurs with high dietary salt intake. The CVOs, including the organum vasculosum lamina terminalis (OVLT) and subfornical organ (SFO), are capable of sensing changes in the salt concentration in the blood and mediate salt-induced changes in sympathetic nerve activity (SNA), vasopressin (AVP), thirst, and blood pressure (BP). Central salt sensing is also associated with the development of salt sensitive hypertension in rodents. Studies in humans demonstrate that acute relative hypernatremia alters the activity or functional connectivity of the CVOs. However, no studies have investigated whether there are sex differences in central neural activation during acute hypernatremia in humans, which could underly sex differences in neurohumoral responses to salt loading. Therefore, the purpose of this study was to investigate whether there are sex differences in the activation patterns of salt sensing and sympathoregulatory brain regions during acute hypernatremia. Thirty-two young healthy adults (17 men/15 women) underwent blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) at rest and during a 30-minute intravenous (IV) hypertonic saline infusion (3% NaCl). Women were not using hormonal contraception and were tested during the follicular menstrual cycle phase. We calculated fractional amplitude of low frequency fluctuations (fALFF), which reflects the intensity of the spontaneous fluctuations in the BOLD signal in each brain region, and functional connectivity, which reflects the synchronization of low frequency fluctuations in the BOLD signal between our regions of interest. We hypothesized that acute hypernatremia would increase the fALFF in and functional connectivity between brain regions involved in sensing salt and increasing sympathetic outflow, while decreasing in nuclei that inhibit sympathetic outflow. We also hypothesized that these responses would be heightened in men. The main findings of this study were that acute relative hypernatremia increased fALFF in several brain regions associated with salt sensing and thirst, including the SFO, OVLT, anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), insula, and thalamus, and in several sympathoregulatory brain regions, including the paraventricular nucleus (PVN), supraoptic nucleus (SON), rostral ventrolateral medulla (RVLM), nucleus tractus solitarius (NTS), and caudal ventrolateral medulla (CVLM). Overall, changes in fALFF were similar between men and women. This is consistent with the changes observed for serum sodium, thirst, SBP, and plasma AVP, all of which increased to a similar extent between the sexes. However, functional connectivity between the SFO and OVLT increased in men but decreased in women, indicating a sex-specific response. Interestingly, serum testosterone was positively correlated with the change in SFO-OVLT functional connectivity in men and women combined, suggesting that testosterone may impact this response. Collectively, these results demonstrate that, in response to acute relative hypernatremia, these salt sensing and sympathoregulatory brain regions are activated similarly in both men and women tested during the follicular menstrual cycle phase (as assessed by fALFF); however, men seem to have a more synchronized neural response between the SFO and OVLT (as assessed via functional connectivity). This suggests that these regions are more tightly coupled in their neural response to acute hypernatremia in men. These findings set the stage for additional studies to investigate mechanisms of central salt sensing in humans, central salt sensing in the context of chronic salt loading, and sex differences across the lifespan.University of Delaware, Department of Kinesiology and Applied PhysiologyPh.D
Depth and Strain-Dependent Structural Responses of Mouse Lens Fiber Cells During Whole Lens Shape Changes
No full textThis article was originally published in Investigative Ophthalmology & Visual Science. The version of record is available at: https://doi.org/10.1167/iovs.66.2.53.
Copyright 2025 The Authors.
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (http://creativecommons.org/licenses/by-nc-nd/4.0/).Purpose: To study the relationship between whole lens shape changes and fiber cell responses to externally applied loads.
Methods: Freshly dissected mouse lenses were compressed by applying glass coverslips to the lens anterior, followed by fixation to preserve lens shape, and preparation for scanning electron microscopy (SEM). SEM images were collected from the outer cortex to the nucleus, and fiber cell end-to-end curvature and membrane paddle dimensions were measured using ImageJ.
Results: At 23% and 29% axial strain, cortical fiber bundle curvature increased significantly compared to control uncompressed lenses, whereas nuclear fiber bundle curvature was unaffected. Outer cortical fiber cell membrane paddles and protrusions were dramatically distorted in a radial direction, with loss of paddle-associated small protrusions in compressed lenses compared to controls, but nuclear fiber cell morphologies were unchanged. The compression-induced increases in cortical fiber cell curvature and distortion of membrane paddles were reversible, with fiber cell morphologies returning to those of control lenses after the release of load.
Conclusions: Whole lens shape changes due to an increase in axial strain result in increased fiber cell curvature and distorted membrane morphologies in cortical but not nuclear fiber cells, indicating that mechanical strain dissipates with depth. The recovery of normal cortical fiber cell curvature and membrane morphologies after the removal of load and lens rounding back to its original shape suggests elastic properties of the young and mature fiber cells and their membrane paddles.Supported by NIH-NEI grant R01 EY017724 (to V.M.F., J.P. and W.K.L.), and by a Core Center Access Award (to V.M.F.) from NIH-NIGMS grant P20 GM103446) to Delaware-INBRE
First whole-genome sequence of Triatoma sanguisuga (Le Conte, 1855), vector of Chagas disease
No full textThis article was originally published in Genes | Genomes | Genetics Published by Oxford University Press. The version of record is available at: https://doi.org/10.1093/g3journal/jkae308.
© The Author(s) 2024. Published by Oxford University Press on behalf of The Genetics Society of America.
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 reuse, distribution, and reproduction in any medium, provided the original work is properly cited.Triatoma sanguisuga is the most widespread triatomine bug species in the United States. The species vectors the human parasite Trypanosoma cruzi, which causes Chagas disease. Vector-borne Chagas disease is rarely diagnosed in the United States, but T. sanguisuga has been implicated in a handful of cases. Despite its public health importance, little is known about the genomics or population genetics of T. sanguisuga. Here, we used long-read sequencing to assemble the first whole-genome sequence for T. sanguisuga using DNA extracted from 1 adult specimen from Delaware. The final size of the genome was 1.162 Gb with 77.7× coverage. The assembly consisted of 183 contigs with an N50 size of 94.97 kb. The Benchmarking Universal Single-Copy Ortholog complete score was 99.1%, suggesting a very complete assembly. Genome-wide GC content was 33.56%, and DNA methylation was 18.84%. The genome consists of 62.75% repetitive DNAs and 17,799 predicted coding genes. The assembled T. sanguisuga genome was very close in size and BUSCO score to that of Triatominae species T. dimidiata (1.16 Gb with 99.1% BUSCO score for T. sanguisuga vs 1.22 Gb with 98.7% BUSCO score for T. dimidiata) and slightly larger than that of T. infestans and Rhodnius prolixus (949 Mb with 90.4% BUSCO score and 706 Mb with 96.5% BUSCO score, respectively). The T. sanguisuga genome is the first North American triatomine species genome to be sequenced, allowing for deeper investigations into epidemiologically relevant aspects of triatomines in temperate climates, thus providing potential vector-borne disease management targets and strengthening public health preparedness.Access to the University of Delaware Sequencing and Bioinformatics Core Centers was supported by the Institutional Development Award (IDeA) program from the National Institute of General Medical Sciences – NIGMS (P20 GM103446) from the National Institutes of Health. Support from the University of Delaware CBCB Bioinformatics Data Science Core Facility (RRID:SCR_017696) including use of the BIOMIX and BioStore computational resources was made possible through funding from Delaware INBRE (NIGMS P20 GM103446), NIH Shared Instrumentation grant (S10 OD028725), the State of Delaware, and the Delaware Biotechnology Institute. We would also like to acknowledge support from USDA Hatch (DEL00854 and NE1943)
Bacteria-Produced Algicide for Field Control of Toxic Dinoflagellates Does Not Cause a Cortisol Stress Response in Two Estuarine Fish Species
No full textThis article was originally published in Marine Biotechnology. The version of record is available at: https://doi.org/10.1007/s10126-024-10383-z.
© The Author(s) 2025.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Application of algicides produced by naturally occurring bacteria is considered an environmentally friendly approach to control harmful algal blooms. However, few studies assess the effects of bacterial algicides on non-target species, either independently or with other stressors. Here, we measured sub-lethal effects of dinoflagellate-specific algicide IRI-160AA on the estuarine fish Fundulus heteroclitus and Menidia menidia in laboratory experiments. Plasma cortisol levels were measured to test whether a neuroendocrine stress response was induced in these fish following exposure to the algicide alone, and in combination with diel-cycling hypoxia and/or pH, at 25 and 30 °C. Results show that exposure to IRI-160AA does not significantly affect cortisol levels in either species, at either temperature tested, whether exposure occurs independently or with co-occurring hypoxia and/or pH cycles as potential multiple stressors. These results support the application of IRI-160AA as an environmentally friendly approach to control harmful algal blooms in estuarine environments.Funding was provided by the National Oceanic and Atmospheric Administration; Prevention, Control, and Mitigation of Harmful Algal Blooms (NOAA PCMHAB) program (award #NA15NOS4780176; contribution #70) and the University of Delaware
Mechanical Properties of the Cortex in Older Adults and Relationships With Personality Traits
No full textThis article was originally published in Human Brain Mapping. The version of record is available at: https://doi.org/10.1002/hbm.70147.
© 2025 The Author(s). Human Brain Mapping published by Wiley Periodicals LLC.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.Aging and neurodegeneration impact structural brain integrity and can result in changes to behavior and cognition. Personality, a relatively stable trait in adults as compared to behavior, in part relies on normative individual differences in cellular organization of the cerebral cortex, but links between brain structure and personality expression have been mixed. One key finding is that personality has been shown to be a risk factor in the development of Alzheimer's disease, highlighting a structure–trait relationship. Magnetic resonance elastography (MRE) has been used to noninvasively study age-related changes in tissue mechanical properties because of its high sensitivity to both the microstructural health and the structure–function relationship of the tissue. Recent advancements in MRE methodology have allowed for reliable property recovery of cortical subregions, which had previously presented challenges due to the complex geometry and overall thin structure. This study aimed to quantify age-related changes in cortical mechanical properties and the relationship of these properties to measures of personality in an older adult population (N = 57; age 60–85 years) for the first time. Mechanical properties including shear stiffness and damping ratio were calculated for 30 bilateral regions of the cortex across all four lobes, and the NEO Personality Inventory (NEO-PI) was used to measure neuroticism and conscientiousness in all participants. Shear stiffness and damping ratio were found to vary widely across regions of the cortex, upward of 1 kPa in stiffness and by 0.3 in damping ratio. Shear stiffness changed regionally with age, with some regions experiencing accelerated degradation compared to neighboring regions. Greater neuroticism (i.e., the tendency to experience negative emotions and vulnerability to stress) was associated with high damping ratio, indicative of poorer tissue integrity, in the rostral middle frontal cortex and the precentral gyrus. This study provides evidence of structure–trait correlates between physical mechanical properties and measures of personality in older adults and adds to the supporting literature that neurotic traits may impact brain health in cognitively normal aging.This work was supported by a grant from the National Institutes of Health, R01-AG058853. Additional resources were provided by the Delaware Center for Cognitive Aging Research and the University of Delaware Center for Human Research Coordination
Deriving Models of Change with Interpretable Parameters: Linear Estimation with Nonlinear Inference
No full textThis article was originally published in Psychometrika. The version of record is available at: https://doi.org/10.1017/psy.2024.2.
© The Author(s), 2025. Published by Cambridge University Press on behalf of Psychometric Society.
This is an Open Access article, distributed under the terms of the Creative Commons Attribution-NonCommercial licence (https://creativecommons.org/licenses/by-nc/4.0), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original article is properly cited. The written permission of Cambridge University Press must be obtained prior to any commercial use.In modeling change over time, developmental theories often emphasize meaningful quantities like peaks, inflections, timing, and tempo. However, longitudinal analyses typically rely on simple polynomial models that estimate powered terms of time in a linear, additive form which are disconnected from these meaningful quantities. While these linear parameterizations are computationally efficient and produce stable results, the quantities estimated in these models are difficult to directly connect to theoretical hypotheses. To address this disconnect between estimation and theory development, I propose several approaches for linear estimation with nonlinear inference (LENI), a framework that transforms results from stable, easily-estimated linear models into nonlinear estimates which align with theoretical quantities of interest through a set of principled transformation functions. I first outline derivations for the interpretable nonlinear parameters, and transform the results of the corresponding linear model—including fixed and random effects as well as conditional covariates effects —into the results we would have obtained by fitting a nonlinear version of the model. I conclude by summarizing a linearized structural equation model approach which can flexibly accommodate any known nonlinear target function within a linearly-estimable framework. I conclude with recommendations for applied researchers and directions for fruitful future work in this area.EMM was supported with funds from the NWO (Nederlandse Organisatie voor Wetenschappelijk Onderzoek), Domain Social Sciences and Humanities (SSH) Sector Plan: Resilience in Youth, and Jacobs Foundation Fellowship 2023-1510-00. Special thanks go to supportive colleagues including Dr. G.686 R. Hancock, Dr. R. A. Kievit, and Dr. P. J. Curran for critical feedback on the article