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Behavior of Earthquake-Resistant Reinforced Concrete Column-Foundation Connections
No full textResults from these tests can be found at this reference:
Neupane, U., Niyonyungu, F., Lequesne, R. D., Lepage, A., and Darwin, D., DATASET: Results from Cyclic Tests of Reinforced Concrete Column-Foundation Connections, KU Scholarworks, Lawrence, KS, January 2025. https://hdl.handle.net/1808/35803Reversed-cyclic tests of large-scale reinforced concrete column-foundation connections with hooked column longitudinal bars were performed to investigate the mechanisms of moment-transfer and breakout failure. Two tests were conducted and then analyzed in combination with results from four tests reported in Niyonyungu (2024) and one test reported in Chen (2021). The columns were 2-ft (605 mm) square and longitudinally-reinforced with 12 or 16 No. 8 (25 mm) bars. Other variables included column hooked-bar embedment length (15 or 19 times the column bar diameter), foundation thickness (18 or 30 in. (460 or 760 mm)), the presence or absence of foundation shear reinforcement, and foundation flexural reinforcement (No. 6 (19 mm) bars spaced at 5.5, 9, or 12 in. (140, 225, or 300 mm) in two directions). The nominal concrete compressive strength was 6000 psi (42 MPa) and reinforcement was Grade 60 (420).
Test results show that specimen strength was limited by column bar yielding and drift ratio capacity was governed by breakout. Results show that, for connections like those tested, drift ratio increases when either: a) column longitudinal bar yield strain penetration from the top of the foundation to the onset of the bends is delayed, or b) breakout resistance is increased. Increased foundation longitudinal reinforcement ratio and longer column bar embedment both delayed yielding at the onset of the column-bar bend and correlated with greater drift ratio capacity. Providing foundation shear reinforcement with shear strength exceeding 40% of the transfer moment based on the eccentric shear stress model, ignoring the concrete contribution, was shown to delay breakout and increase drift ratio capacity. The top mat of foundation reinforcement participated more in resisting transfer moment than implied by a strength model based on equal participation of top and bottom mats, indicating the top mat of reinforcement should be designed for the full transfer moment instead of splitting the reinforcement between top and bottom mats. Top mat strains, which were much more sensitive to column bar embedment length than to foundation depth, were largest within the column width and decreased as the distance from the column face increased up to approximately 1.5 times the column hooked-bar embedment length, suggesting that the concept of a transfer width is useful for designing foundations for column moment transfer. Taken together with the observation that top mat strains were more affected by column hooked-bar embedment length than foundation thickness, the definition of transfer width for moment transfer calculations should based on column bar embedment length.The Electric Power Research Institut
Bees display limited acclimation capacity for heat tolerance
No full textBees are essential pollinators and understanding their ability to cope with extreme temperature changes is crucial for predicting their resilience to climate change, but studies are limited. We measured the response of the critical thermal maximum (CTMax) to short-term acclimation in foragers of six bee species from the Greek island of Lesvos, which differ in body size, nesting habit, and level of sociality. We calculated the acclimation response ratio as a metric to assess acclimation capacity and tested whether bees’ acclimation capacity was influenced by body size and/or CTMax. We also assessed whether CTMax increases following acute heat exposure simulating a heat wave. Average estimate of CTMax varied among species and increased with body size but did not significantly shift in response to acclimation treatment except in the sweat bee Lasioglossum malachurum. Acclimation capacity averaged 9% among species and it was not significantly associated with body size or CTMax. Similarly, the average CTMax did not increase following acute heat exposure. These results indicate that bees might have limited capacity to enhance heat tolerance via acclimation or in response to prior heat exposure, rendering them physiologically sensitive to rapid temperature changes during extreme weather events. These findings reinforce the idea that insects, like other ectotherms, generally express weak plasticity in CTMax, underscoring the critical role of behavioral thermoregulation for avoidance of extreme temperatures. Conserving and restoring native vegetation can provide bees temporary thermal refuges during extreme weather events
Auditing the Representation of Female Athletes in Sports Medicine Research: Fifth-Metatarsal Fractures
No full textA grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Background:
Female representation within athletics has increased as a result of Title IX, rising popularity, demand for equal compensation, and greater participation in multiple sports. Despite this, gender disparities in sports medicine research are apparent. This project serves to review the literature available on fifth-metatarsal fractures and assess the representation of female athletes in current literature.
Methods:
We used a standardized protocol to audit the representation of female athletes in sports science and sports medicine research for fifth-metatarsal fractures. Primary factors included population, athletic caliber, menstrual status, research theme, sample of males and females, journal impact factor, and Altmetric score.
Results:
Thirty articles met the inclusion criteria. A total of 472 fifth-metatarsal fractures were identified, with 373 of 472 fractures (79%) occurring in males and 99 of 472 (21%) in females. The majority of studies (18/30, 60%) were mixed cohort, followed by 10 male only (33.33%), 1 female only (3.33%), and 1 male vs female (3.33%). Out of 831 total patients in the 18 mixed-cohort studies, 605 of 831 patients (72.8%) were male and 226 of 831 patients (27%) were female. All 18 mixed-sex cohorts investigated health outcomes. Male-only studies evaluated health outcomes and performance metrics. No studies investigated female performance. The one female-only study investigated health outcomes and was the only study to account for menstrual status. There was a single metatarsal fracture in this study population.
Conclusion:
Females are underrepresented in research regarding sports science and sports medicine research for fifth-metatarsal fractures. Research focused on female-only fifth-metatarsal fracture studies exploring the potential impact of female sex–specific factors such as menstrual status in study design are needed
Ecosystems Designed for Change: An Evaluation Framework for Innovators & Leaders
No full textThis white paper in the Responsive Ecosystems for Change Series presents an evaluation framework to guide practitioners and ecosystem leaders toward a comprehensive approach for measuring change and impact. It discusses methodologies and analyses specifically designed for complex systems change at many levels. This paper walks readers through the framework, concepts, and examples to improve their understanding of how to evaluate a social ecosystem and measure its collective impact at scale
The impact of agricultural colonization and deforestation on orchid bees (Apidae: Euglossini) in the Brazilian Amazon
No full textResearchers have studied orchid bees for decades to determine the impact of tropical deforestation on biodiversity. Our objective was to determine impacts on orchid bees at scales other than forest patches/fragments, as called for in the broader literature on the impacts of habitat fragmentation on biodiversity. We examine an orchid bee survey, which employed chemical baits and live netting in rapid assessments, across the entire state of Rondônia in the Brazilian Amazon. We analyze the relationships between age of agricultural settlement of collection zones and the immediate land cover (closed vs. open canopy of land use/land cover) of collection sites on orchid bee abundance, richness, and composition. The survey reveals a highly diverse community (2497 individuals, represented by 5 genera and 48 species across 12 collection zones and 130 sample locations). Species richness declined significantly between conservation units and older settlement zones, but richness in newer settlement zones remained at an intermediate, insignificantly different level. Significantly greater abundance was found within conservation units, less in newer settlement zones, and even less in older settlement zones. Species composition was significantly different when comparing the conservation unit and older settlement categories of collection zone. Closed canopy species richness and abundance were significantly higher than that found in open canopy. Composition also differed significantly between open and closed canopy land cover canopy types. Eulaema nigrita and several Euglossa species are identified as particularly strong indicators of degraded and preserved environments, respectively
Identification of the chaA and fwA Spore Color Genes of Aspergillus nidulans
No full textWild-type asexual spores (conidia) are green due to a pigment that protects the spores against ultraviolet light. The pigment is produced by a biosynthetic pathway, the genes of which are dispersed in the genome. The backbone molecule of the pigment is a polyketide synthesized by a polyketide synthase encoded by the gene. If is not functional, the conidia are white. The polyketide is modified by a laccase encoded by the gene and inactivation of in an otherwise wild-type background results in yellow spores. Additional spore color mutations have been isolated and mapped to a locus genetically, but the genes that correspond to these loci have not been determined. Spore color markers have been useful historically, and they remain valuable in the molecular genetics era. One can determine if a transforming fragment has been successfully integrated at the or locus by simply looking at the color of transformant conidia. The genes of the potentially useful color loci (chartreuse conidia) and (fawn conidia) have not been identified previously. We chose a set of candidate genes for each locus by comparing the assembled genome with the genetic map. By systematically deleting these candidate genes, we identified a cytochrome P450 gene (AN10028) corresponding to . Deletions of this gene result in chartreuse conidia and chartreuse mutations can be complemented in trans by a functional copy of this gene. With , we found that the existing fawn mutation, , is a deletion of 2241 base pairs that inactivates three genes. By deleting each of these genes, we determined that is AN1088, an EthD domain protein. Deletion of AN1088 results in fawn conidia as expected. Neither deletion of nor restricts growth and both should be valuable target loci for transformations. Combinations of deletions have allowed us to investigate the epistasis relationships of , , and
Women and men in library and information science scholarship: Authorship trends from 2003 to 2021
No full textLibrary and information science (LIS) has long consisted of more women than men, at least in sheer numbers of library employees, but men are the primary authors of library literature. This study explores LIS literature published between 2003 and 2021 to identify if there are differences in the publishing patterns of women and men. The authors used content analysis to code the entire sample to identify overall subject trends after authors were categorized as women or men by mainly automated methods, using two R packages, genderize and ssa. The results show that there are overall inequities when compared to the profession as whole between the publishing rates of women and men in LIS, as well as differences in publication patterns by subjects and within specific journals. Shifts in subjects over the period under investigation did not increase the percentage of women publishing in the selected LIS journals. The authors conclude more research needs to be conducted to determine the cause of inequities in publishing not just among women and men, but all underrepresented voices in LIS
Compression Lap Splices and Compression Development of Headed and Hooked Bars in Beam-Column Joints
No full textACI 318-19 Building Code provisions for compression lap splices and for headed and hooked bar development in special moment frame (SMF) joints were evaluated against databases of test results. Recommendations are made for simplifying and improving code requirements.
Compression lap splice length provisions (ACI 318-19 §25.5.5) produce calculated lengths longer than Class B tension lap splice lengths under certain design conditions. The provisions were shown to also be a poor fit to a database of 89 test results (with 72 specimens in the database violating the ACI 318-19 minimum lap splice length). Several equations exist that better fit the dataset, including several tension development length equations. Defining compression lap splice length requirements as a function of the tension development length is a more accurate alternative to §25.5.5 that eliminates the need to calculate both tension and compression development lengths and prevents design cases where calculated lengths are longer in compression than in tension.
Provisions for headed and hooked bar development were compared against databases of exterior beam-column connection tests with 35 and 27 specimens, respectively. Analyses show that satisfying the compression development length requirements of §25.4.9, as mandated by §18.8.2.2, is not necessary for preventing anchorage distress in special moment frame joints with either headed or hooked bars. None of the 59 specimens (35 with headed bars and 24 with hooked bars) with drift ratio capacities above 3% satisfied §25.4.9. The analyses also show that joints that did not satisfy the ACI 318-19 provisions for headed or hooked bar tension development length (§18.8.5.2 for headed bars and §25.4.3 for hooked bars) still exhibited satisfactory behavior, suggesting that §18.8.5.2 and §25.4.3 are considerably conservative. Other equations were evaluated and found to better fit the data, including the equation in ACI 318-19 §18.8.5.1, which analyses suggest might be applicable to both headed and hooked bars.Concrete Reinforcing Steel Institute Education and Research Foundatio
