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Detected Abundances of Nuclei Relative to 26Fe for Elements 14Si through 44Ru with CALET on the International Space Station
No full textThe Calorimetric Electron Telescope (CALET), launched to the International Space Station (ISS) in 2015 August and continuously operating since, measures cosmic-ray (CR) electrons, nuclei, and gamma rays. CALET, with its 27 radiation length deep Total Absorption Calorimeter, measures particle energy and allows for the measurement of spectra, secondary to primary ratios of the more abundant CR nuclei through 28Ni, while the main charge detector can measure ultra-heavy CR nuclei through 44Ru. The results for the abundances of elements from Z = 14 to Z = 44 relative to 26Fe over 7.5 yr of observation are presented here and compared to previous measurements from ACE-CRIS, SuperTIGER, and HEAO-3
Fermi detection of gamma-ray emission from the hot coronae of radio-quiet active galactic nuclei
No full textRelativistic jets around supermassive black holes are well-known powerful γ-ray emitters. In the absence of the jets in radio-quiet active galactic nuclei, how the supermassive black holes work in γ-ray bands is still unknown despite great observational efforts in the past three decades. Here, considering the previous efforts, we carefully select an active galactic nucleus sample composed of 37 nearby Seyfert galaxies with ultrahard X-rays for γ-ray detection by excluding all potential contamination in this band. Adopting a stacking technique, we report the significant γ-ray detection (test statistic 30.6, or 5.2σ) from the sample using 15-year Fermi-LAT observations. We find the average γ-ray luminosity of the sample to be (1.5 ± 1.0) × 1040 erg s−1 at energies of 1–300 GeV. Limited by the well-known pair production from the interaction of γ-rays with low-energy photons, γ-rays of more than several giga-electronvolts are found to originate from an extended corona (~2.7 × 106 gravitational radii), whereas the canonical much more compact X-ray corona (~10 gravitational radii) is responsible for γ-rays of one to several giga-electronvolts. The finding of the compact region lends strong support to the long-time theoretical expectations, but the extended corona is an unexpected finding. One promising scenario is that the electron–positron pairs produced in the compact X-ray corona would expand as a fireball, similar to that in γ-ray bursts, forming the structure of extended corona
A polarized view of the young pulsar wind nebula 3C 58 with IXPE
No full textPulsar wind nebulae (PWNe) are among the most efficient particle accelerators in the Universe; however, the physical conditions and magnetic geometry in their inner regions remain poorly understood. X-ray polarization now provides a unique opportunity to investigate the magnetic field structure and turbulence properties close to the sites where high energy particles are accelerated. Here, we report on recent X-ray polarization measurements of the PWN 3C 58 by the International X-ray Polarimeter Explorer (IXPE). 3C 58 is a young system that displays a characteristic jet-torus structure that, unlike those in other PWNe, is observed almost edge-on. This nebula exhibits a high level of integrated polarization, approximately 22%, at an angle near 97, with an implied magnetic field oriented parallel to the major axis of the inner torus. This suggests a toroidal magnetic geometry with little turbulence in the interior and an intrinsic level of polarization possibly approaching the theoretical limit for synchrotron emission. No significant detection of a polarized signal from the associated pulsar was found. These results confirm that the internal structure of young PWNe is far less turbulent than previously predicted and is at odds with multidimensional numerical simulations
Supporting Managed Honey Bee (Apis mellifera) Health with Diverse Natural Products: Impacts on Nutrition, Immunity, and Gut Microbiota
No full textTo support honey bee (Apis mellifera L.) colony health in the context of modern agricultural systems, which are often characterized by many interacting abiotic and biotic factors that harm pollinator health, beekeepers tend to implement a variety of hive treatments. The exact treatment regimen used can depend on beekeepers’ geography, operation size, and goals, but most often includes supplemental nutrition, miticide treatments, and antibiotics. Growing awareness of the downsides of artificial and synthetic chemical inputs, in addition to some longstanding beekeeper preferences for “natural” management styles, has contributed to the popularization of natural product-based feed additives to support colony health. However, despite the widespread use and anecdotal benefits of such products, several knowledge gaps persist regarding their specific effects on bee health.
In this dissertation, I investigate the impacts of plant- and microalgae-derived natural product feed additives on honey bee health, focusing on the impacts on worker nutrition, immunity, and gut microbiota. Essential oils and propolis extracts exhibited mostly positive impacts on worker lifespan while supporting a healthy core gut microbiome. Spirulina and Chlorella feed additives improved longevity, and spirulina additionally stimulated key immune responses. These immunostimulatory effects, however, did not translate to improved survival or resistance to the microsporidian gut parasite Nosema ceranae. Additionally, artificial diets containing microalgae ingredients result in distinct gut microbiome composition and reduced gut symbiont strain diversity compared to diets containing natural pollen, those these effects were mediated by the honey bee’s genetic background. These findings contribute to a stronger understanding of how natural product feed ingredients can support honey bee health and open the door for future research to further optimize feed additives for bees
Examining Diet Quality and Food Insecurity Among Louisiana EFNEP Participants
No full textFor nearly 6 decades, the Expanded Food and Nutrition Education Program (EFNEP) has served marginalized communities by providing peer-led nutrition education to improve dietary behaviors and practices and addressing food insecurity among low-income families. Despite its longstanding impact with limited resource audiences, limited research has examined how EFNEP participant data can be leveraged to assess both diet quality and food insecurity in Louisiana.
This study utilized quantitative design through secondary analysis of data from EFNEP’s Web-Based Nutrition Education Evaluation and Reporting System (WebNEERS). The research examined participant demographics, perceptions of diet quality and food security, and food choice behaviors before and after program participation. Key objectives included evaluating EFNEP’s influence on perceptions of dietary behavior, understanding the role of food insecurity in diet quality, and identifying barriers and facilitators to improve nutrition in LSU AgCenter’s EFNEP framework.
The study sample consisted of 102 EFNEP graduates., with 70.3% identifying as Black or African American, 76.8% as women, 54.9% reporting living in towns under 10,000 and non-rural farms, and 56.9% reporting an education level of less than a college degree. Findings revealed modest improvements in food-related behaviors, including diet quality, food resource management, and food security. Statistically significant differences were observed in post-program perceptions of diet quality (p \u3c .05) and healthy eating behaviors (p \u3c .01). Female participants and those with higher education attainment reported greater adoption of healthy eating behaviors, suggesting EFNEP-acquired skills.
The findings contribute to the academic literature on nutrition education and food insecurity among limited-resource populations in Louisiana. Results provide EFNEP administrators with evidence to strengthen and realign the program to effectively in address dietary behaviors and food insecurity throughout statewide among vulnerable populations
The Multiband Imaging Survey for High-alpha PlanetS (MISHAPS). I. Preliminary Constraints on the Occurrence Rate of Hot Jupiters in 47 Tucanae
No full textThe first generation of transiting planet searches in globular clusters yielded no detections, and in hindsight only placed occurrence rate limits slightly higher than the measured occurrence rate in the higher-metallicity Galactic thick disk. To improve these limits, we present the first results of a new wide-field search for transiting hot Jupiters in the globular cluster 47 Tucanae (47 Tuc). We have observed 47 Tuc as part of the Multiband Imaging Survey for High-Alpha PlanetS. Using 24 partial and full nights of observations taken with the Dark Energy Camera on the 4 m Blanco telescope at Cerro-Tololo Interamerican Observatory, we perform a search on 19,930 stars in the outer regions of the cluster. Though we find no clear planet detections, by combining our result with the upper limit enabled by R. L. Gilliland et al.’s Hubble search for planets around an independent sample of 34,091 stars in the inner cluster, we place the strongest limit to date on hot Jupiters with periods of 0.8 ≤ P ≤ 8.3 days and 0.5RJup ≤ RP ≤ 2.0RJup of fHJ \u3c 0.11%, a factor of ∼4 below the occurrence rate in the Kepler field. Our search found 35 transiting planet candidates, though we are ultimately able to rule out each without follow-up observations. We also found four eclipsing binaries (EBs), including three previously uncataloged detached EB stars
Phase-amplitude separation of wave function as local gauge transformation
No full textA quantum-mechanical wave function is complex, but all observations are real, expressible through expectation values and transition matrix elements that involve the wave functions. It can be useful to separate at the outset the amplitude and phase as real quantities that together carry the same information that is contained in the complex wave function. Two main avenues for doing so go way back in the history of the subject and have been used both for scattering and bound states. A connection is made here to gauge transformations of electrodynamics where the advent of quantum mechanics and later quantum field theory showed the central role that local gauge transformations play in physics
EXPLORING THE RECOGNITION OF INTERNALIZING PROBLEMS AMONG BLACK STUDENTS: DELVING INTO THE YOUTH MENTAL HEALTH HELP-SEEKING PATHWAY
No full textThe mental health of Black adolescents is a growing concern, with high prevalence rates of internalizing disorders such as anxiety and depression. National studies report that nearly 47% of Black adolescents experience a mental health disorder by age 18, with over 60% reporting moderate to severe depressive symptomology. Despite these alarming rates, Black youth underutilize mental health services, often due to cultural stigma, limited access to culturally competent care, and under-recognition of their mental health needs. This study aimed to explore problem recognition as a key component in the mental health help-seeking pathway for Black adolescents in school settings. Grounded in the Youth Help-Seeking Pathway (YHSP) framework, the research focuses on the initial stage of problem recognition—whether Black youth can identify internalizing symptoms of anxiety and depression and have positive intentions of seeking school-based mental health help. The study also investigates the role of gender, school connectedness, cultural stigma, and the perceived cultural responsiveness of the school environment as potential factors influencing problem recognition and help-seeking intent. Data was collected from a sample of 5th-8th grade Black/African American students (N = 197) in a southern Louisiana school using a combination of mental health screening tools, demographic questionnaires, and scales measuring school environment perceptions. Through this research, we explored barriers and facilitators influencing Black students\u27 mental health service use to develop culturally-responsive programming to promote early identification and help-seeking in the schools. The results confirmed a significant positive correlation between internalizing symptom severity and problem recognition (r = .40, p \u3c .001), and contrary to assumptions of underreporting, Black students exhibited a high sensitivity rate (82%) in recognizing clinical-level distress. Participants overwhelmingly reported reliance on informal supports such as parents/caregivers (61.4%) and friends (57.6%), as well as self-reliance, over seeking help from formal school mental health staff. Critically, the intention to seek help from school personnel was not primarily driven by clinical need, but was significantly predicted by environmental factors, including school connectedness and perceived diverse teaching practices, underscoring the necessity of creating culturally safe and inclusive school environments for Black students
Bomba E: Tradition and Eclecticism in Selected Choral Works of Ángel Cucco Peña
No full textThis monograph presents a musical analysis of three choral works by Puerto Rican composer Ángel “Cucco” Peña: Negra Majestad, Bomba E, and Aleluya Criollo. Although Peña is widely recognized for his contributions to popular music and production, these pieces highlight a lesser-known side of his creative output in the choral realm. Each work draws from traditional Puerto Rican genres—bomba, plena, and aguinaldo—while incorporating modern compositional techniques that reflect Peña’s eclectic style and his engagement with both popular and classical traditions.
The study situates these pieces within their historical and cultural contexts, particularly the African diaspora’s influence on Puerto Rican identity. Through a combination of harmonic and rhythmic analysis, text study, and interpretive insights from interviews with the composer, this research examines how Peña adapts Afro-Puerto Rican idioms into a choral language. Key features identified include the integration of rhythmic units characteristic of bomba and plena, instrumental onomatopoeia in the vocal lines, and idiomatic writing that imitates the textures of traditional Puerto Rican ensembles. His harmonic language blends tonal and modal approaches, frequently incorporating chromatic modulations, jazz sonorities, and rich divisi textures while preserving melodic clarity and tonal centers.
Findings suggest that Peña’s choral works function not only as artistic compositions but also as cultural artifacts, encapsulating Puerto Rico’s layered traditions and its ongoing dialogue with global musical practices
Optimizing a Cooperative Procurement Policy of Perishable Precast Materials for a Single Buyer, Single Manufacturer under Demand and Lead Time Uncertainty
No full textModern innovations have made it possible to cast concrete elsewhere and then place it in buildings or other construction sites as needed and this technique is called precast. Precast materials have a limited shelf life, so considering it in planning, inventory, and supply-chain design helps reduce waste and keep materials dependable in modern construction. Efficient management of precast concrete supply chain is essential for ensuring that construction projects of various transportation infrastructures are completed on time and within budget. This research introduces an integrated inventory model based on a cooperative policy between a single precast manufacturer and a single precast material vendor. Unlike traditional inventory models that assume constant demand, this study incorporates probabilistic demand to reflect market variability more realistically. Additionally, the perishability of various precast materials is explicitly considered, influencing the inventory and procurement strategies significantly. The developed model aims to minimize the integrated cost of inventory management, accounting for ordering, holding, backordering, perishability-related wastage, and penalty costs incurred from delayed shipments beyond specified thresholds. A nonlinear mathematical formulation captures these complex interactions and serves as the basis for deriving optimal inventory policies, including reorder points and order quantities. The solution methodology combines analytical solutions with iterative numerical techniques, accommodating diverse scenarios with varying probabilistic demand distributions. Numerical examples illustrate the practical application and efficacy of the proposed model, offering critical insights for precast concrete supply chains aiming to balance cost-efficiency and material utilization effectively