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Motivations for early high-profile FRIB experiments
No full textThis white paper is the result of a collaboration by many of those that attended a workshop at the facility for rare isotope beams (FRIB), organized by the FRIB Theory Alliance (FRIB-TA), on ‘Theoretical Justifications and Motivations for Early High-Profile FRIB Experiments’. It covers a wide range of topics related to the science that will be explored at FRIB. After a brief introduction, the sections address: section 2: Overview of theoretical methods, section 3: Experimental capabilities, section 4: Structure, section 5: Near-threshold Physics, section 6: Reaction mechanisms, section 7: Nuclear equations of state, section 8: Nuclear astrophysics, section 9: Fundamental symmetries, and section 10: Experimental design and uncertainty quantification
Genomic Insights to Shrew (Mammalia: Soricidae) Evolution: From Rapid Radiations to Morphological Innovations
No full textUncovering the genetic components of adaptation is fundamental for understanding evolution by natural selection. Recently, genomic analyses have been applied to an increasing number of non-model organisms to better explain the evolution of biodiversity. I applied analyses of whole genome datasets to better understand the evolutionary history of Sulawesi white-toothed shrews (genus Crocidura) and phenotypic evolution in the hero shrew, Scutisorex somereni.
Sulawesi is a large Indonesian island located in the Wallacea biogeographic region of the Indo-Australian Archipelago. Many lineages that colonized Sulawesi have undergone in-situ diversification, resulting in a high number of endemic species arising over relatively short geological timescales. One such lineage is Crocidura, which comprises 20 endemic species.
Previous work describing the diversity of Crocidura in Sulawesi used molecular and morphological analyses and found well-supported species boundaries. However, interspecific relationships were less resolved. To better understand evolutionary history in Sulawesi Crocidura, I assembled a large, whole-genome variant dataset that I used to estimate phylogenies. I inferred a well-supported phylogeny for Sulawesi Crocidura which is a critical tool for understanding evolution in this clade.
Using the variant dataset together with the well-supported phylogeny, I next sought to characterize the evolutionary processes occurring in Sulawesi Crocidura, an exemplar system for studying rapid radiation. I found a signal of low-magnitude geneflow, which was widespread and statistically significant. I hypothesize that parallel speciation is the process that has resulted in high species richness but relatively conserved phenotypic diversity in Sulawesi Crocidura.
Scutisorex somereni has what is perhaps the most unique axial skeleton of all vertebrates. Given the distinctiveness of this trait, there is a need to understand the evolution of underlying genomic elements. Using a comparative genomics approach comparing S. somereni to 30 other mammal species, I found HOX genes that were under positive selection. This highlights at least one plausible evolutionary mechanism contributing to this extreme phenotype.
Overall, my dissertation demonstrates how analyses of genomic datasets can be used to understand evolution in non-model species that are difficult to observe
Timing and Spectral Evolution of the Magnetar 1E 1841-045 in Outburst
No full textWe present timing and spectral analyses of Neutron star Interior Composition Explorer (NICER), Nuclear Spectroscopic Telescope Array (NuSTAR), and IXPE observations of the magnetar 1E 1841−045 covering 82 days following its 2024 August bursting activity as well as radio observations utilizing MeerKAT and Effelsberg. We supplement our study with a historical NuSTAR observation and all 2024 preoutburst NICER observations. The outburst is marked by an X-ray flux enhancement of a factor of 1.6 compared to the historical level, predominantly driven by a newly formed nonthermal emitting component with a photon index Γ = 1.5. This flux showed a 20% decay at the end of our monitoring campaign. The radio monitoring did not reveal any pulsed radio emission with an upper limit of 20 mJy and 50 mJy ms on the mean flux density and single pulse fluence, respectively. We detect a spin-up glitch at outburst onset with Δν = 6.1 × 10−8 Hz and Δ ν ̇ = − 1.4 × 1 0 − 14 Hz s−1, consistent with the near universality of this behavior among the continuously monitored magnetars. Most intriguingly, the 1E 1841−045 2-10 keV pulse profile is markedly different compared to preoutburst: it shows a new, narrow (0.1 cycle) peak that appears to shift toward merging with the main, persistently present, pulse. This is the second case of pulse-peak migration observed in magnetars after SGR 1830−0645, and the two sources exhibit a similar rate of phase shift. This implies that this phenomenon is not unique and might present itself in the broader population. The newly formed peak for 1E 1841−045 is nonthermal, with emission extending to ≳20 keV, in contrast to the case of SGR 1830−0645. Our results are consistent with an untwisting magnetic field bundle with migration toward the magnetic pole, perhaps accompanied by plastic motion of the crust
A systematic review of environmentally persistent free radical (EPFR) formation, characteristics, and health effects: are there sufficient data for risk assessment?
No full textEnvironmentally persistent free radicals (EPFRs) are stable free radicals formed on particulate matter (PM) through processes such as combustion and pyrolysis. These free radicals are generated on transition metal oxide surfaces in the presence of aromatic precursors. Exposure to EPFRs occurs primarily via inhalation of PM deriving from combustion, traffic, industrial activities, and both indoor and outdoor burning. Other environmental factors that might generate EPFRs are radon, electronic and tobacco cigarettes. EPFRs exhibit unexpectedly long half-lives, ranging from several weeks to, in some cases, several years. EPFRs may be carbon-centered, oxygen-centered or mixed, identified by g-values exhibited in electron paramagnetic resonance analysis. The radicals undergo redox cycling within aqueous solutions and in biological tissues/fluids triggering production of reactive oxygen species (ROS), comprised primarily of hydroxyl, superoxide, and peroxyl radicals. The stability of EPFRs, their association with PM2.5, and their ability to generate ROS may pose significant concerns for human health. To determine whether there are sufficient data for risk assessment, recent advances were examined in the following important aspects of EPFR research: (1) atmospheric chemistry, (2) human exposures, (3) animal toxicity, and (4) epidemiology. Our review found insufficient epidemiological and exposure studies; however, toxicological data in animals suggested that EPFR inhalation contributes to cardiovascular, respiratory, and metabolic diseases. Although EPFRs are not currently surveyed by a regulatory monitoring system, data indicate their widespread presence in the environment and their potential to initiate/exacerbate diseases
EXTRUSION PROCESSING AND FUNCTIONAL CHARACTERIZATION OF HIGH-VALUE EXTRUDATES FROM CRAWFISH MEAT POWDER AND ENCAPSULATED ASTAXANTHIN
No full textThis study explored the processing of extrudates enriched with crawfish meat powder (CP) and microencapsulated crawfish astaxanthin. The extrudates were produced using CP, chickpea flour (CPF), corn flour (CF), and/or tapioca starch. Proximate analysis revealed that CP contained 12.3% protein and 8.3% fat, while CPF and CF contributed higher fiber and carbohydrate contents, respectively. Extrudates with different CPF: CP ratios significantly affected product properties, including water absorption, expansion, hardness, and color. Extrusion temperature and CP content significantly influenced water retention, expansion, and color, bulk density, and thermal stability. Fourier Transform Infrared (FTIR) spectroscopy and Thermogravimetric Analysis (TGA) confirmed that both ingredient composition and processing temperature influenced starch gelatinization, protein denaturation, lipid oxidation, and product stability. Extraction of astaxanthin from crawfish shells using medium-chain triglyceride (MCT) oil yielded the highest astaxanthin recovery and antioxidant activity, along with lower peroxide and Thiobarbituric Acid Reactive Substances (TBARS) values compared to flaxseed and canola oils. Cold plasma pretreatment did not improve extraction efficiency. Microencapsulation of astaxanthin in MCT oil (MA) through spray drying produced a powder with low water activity (0.46), high radical scavenging activity (65.9%), and a stable fatty acid profile dominated by medium-chain saturated fatty acids. TGA and Differential Scanning Calorimetry (DSC) analyses showed that the encapsulated powder remained stable up to 141 °C, indicating its suitability for high-temperature extrusion.
The effects of extruder screw speed, starch source, and MA inclusion were evaluated. Increasing screw speed from 60 to 120 rpm improved expansion and reduced bulk density, especially in tapioca-based extrudates, which exhibited the most significant expansion and lowest density. MA inclusion of up to 10% enhanced the red-orange coloration and increased antioxidant capacity, especially in tapioca and corn formulations. Protein retention and omega-3 content were highest in tapioca extrudates at 120 rpm, while FTIR confirmed effective incorporation of astaxanthin and MCT oil, as indicated by increased C–H and C=O stretching peaks. The best combination of tapioca starch, 120 rpm, and MA addition resulted in extrudates with superior texture, color, nutrition, and functional properties. Overall, this research demonstrated that adding moderate amounts of CP and MA, combined with optimized extrusion parameters, significantly enhanced the physical and chemical qualities of the extrudates
PHYSIOLOGICAL RESPONSES TO ACUTE AND CHRONIC ENVIRONMENTAL AND OPERATIONAL STRESSORS IN WARFIGHTER PERSONNEL AND POSSIBLE THERAPEUTICS
No full textWarfighter-like personnel face extreme physical and psychological demands that necessitate optimized performance and resilience. This dissertation investigates the physiological and molecular adaptations to acute and chronic physical stressors and evaluates the potential of therapeutic interventions to mitigate negative effects. Three interrelated studies were conducted to address key gaps in understanding the effects of stressors and interventions on performance and recovery.
The first study assessed the impact of a multi-ingredient sport supplement on moderate-intensity exercise performance, muscle damage, oxidative stress, and inflammation. Using a double-blind, placebo-controlled, crossover design, no significant differences were observed between the treatment and placebo groups on the assessed variables, suggesting the need for further exploration under varied conditions or populations.
The second study examined the effects of caloric restriction combined with testosterone supplementation on cytokine dynamics during a 28-day, 1,500 calorie energy deficit. A randomized, double-blind, placebo-controlled design revealed significant increases in circulating concentrations of IL-10, and IFNy in the testosterone group, indicating an increased immunomodulatory response that may support inflammation regulation during sustained physical and nutritional stress. These findings indicate testosterone’s potential to influence cytokine responses during sustained stress and highlight its therapeutic relevance.
The third study focused on circulating plasma miRNA levels in response to high-volume exercise and energy deprivation, with and without testosterone supplementation. Results demonstrated significant alterations in 17 miRNAs between testosterone and placebo groups, while the placebo group showed no significant changes from baseline. These findings emphasize the role of miRNA in cellular communication and adaptation to physical and nutritional stressors, particularly in response to testosterone supplementation.
Overall, the findings of this dissertation provide critical insights into the physiological and molecular mechanisms underpinning recovery, resilience, and performance optimization. Testosterone supplementation emerged as a potent modulator of cytokine activity and exosome-mediated signaling, offering insight as a possible therapeutic intervention for high-stress populations. While the multi-ingredient supplement showed no efficacy, the study highlights the importance of tailoring interventions to specific stress profiles and populations. The identification of exosomal miRNAs as biomarkers offers new avenues for biomarker monitoring and possible precision medicine applications. These results contribute to advancing evidence-based strategies to enhance performance and health in warfighter-like personnel and other high-stress populations
Quantum Panprotopsychism and the Structure and Subject-Summing Combination Problem
No full textIn a previous paper, we have shown that an ontology of quantum mechanics in terms of states and events with internal phenomenal aspects, that is, a form of panprotopsychism, is well suited to explaining consciousness. We have proved there that the palette and grain combination problems of panpsychism and pan-protopsychism arise from implicit hypotheses based on classical physics about supervenience that are inappropriate at the quantum level, where an exponential number of emergent properties and states arise. In this article, we address what is probably the first and most important combination problem of panpsychism: the subject-summing problem originally posed by William James. Due to the indeterminacy of quantum mechanics and its causal openness, this ontology also seems to be suitable for the analysis of the remaining aspects of the structure combination problem that treat about how the structuration capacity of consciousness evolved from primitive animals to humans