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Black Women In Oregon Academia
No full textBlack women scholars are a powerful demographic of intellectuals navigating a haunted house of academia, a structure erected upon the bones of a grotesque past. Black women scholars navigate a complex and often hostile academic landscape, a realm marked by under representation and the insidious interplay of race and gender. Oregon, a state steeped in a sinister history of racial terror, casts a long shadow over its present. Its soil, contaminated by the blood of countless Black lives, serves as a fertile ground for the insidious growth of systemic racism. Until 1905, a malevolent decree barred Black individuals from even setting foot on Oregon\u27s cursed land. A chilling testament to the state\u27s original sin, this edict laid the foundation for a legacy of oppression that continues to haunt its institutions. These women scholars are modern-day exorcists of racism, seeking to cleanse the academic temple of its demonic residue. Their journey is a perilous one, for the ghosts of Oregon\u27s racist past linger, seeking to extinguish the light of their knowledge. This study seeks to illuminate the experiences of Black women scholars as they confront the lingering specters of this oppressive past. By examining their triumphs and challenges, we aim to uncover the systemic barriers that persist within Oregon\u27s academic institutions
A Comprehensive Review of Food Waste Management in Attaining SDG 12.3 Goals: Insights from Asian Countries
No full textFood waste is one of the most important world-wide challenges whose environmental, economic and social impacts have far-reaching effects that include contributing to greenhouse gas emissions, resources depletion as well as the rising levels of food insecurity. These problems are further intensified in Asia due to high rate of urbanization, population growth, changing dietary habits, and lack of waste management facilities. These conditions complicate the fact that countries are increasingly struggling to achieve the United Nations Sustainable Development Goal (SDG) 12.3, which is to ensure that by 2030, half of the world has dropped per-capita food waste, and food losses at the entire supply chain spectrum are cut by half. This review discusses the latest food waste management activities, challenges, and developments in Asian nations based on the evidence found in 170 academic articles published between 2015 and 2025 and chosen according to PRISMA guidelines. This research paper assesses food waste sources different region, treatment, and policy responses, but with special attention to the realm of sustainability and a circular economy. The results indicate that East Asian nations have developed policy-making and waste-to-energy technologies. South Asian countries, on the contrary, remain plagued by structural issues, such as poor waste separation, lack of experience, low awareness of the population, and poor infrastructure. Such cross-cutting concerns as land shortages, financial constraints, and ineffective policy enforcement also make it less likely to achieve SDG 12.3. In general, the review determines some important gaps, regional differences and potential areas of improvement of food waste management systems in Asia. Therefore, this review shows the necessity of consistent strategies, more coordination, and better interaction with the population to contribute to sustainable and effective food waste reduction solutions throughout the region
Implementation of Soil Improvement Techniques in the Dhaka Mass Rapid Transit Project a Comprehensive Case Study
No full textThis paper evaluates Sand Compaction Pile (SCP) and Dynamic Compaction (DC) methods for enhancing soft soil in the Dhaka Mass Rapid Transit (MRT) project. Targeted interventions were required for the stratified soil profile, consisting of liquefiable sand (3–5 m thick) over soft clay (SPT ∼5): dynamic compaction for densifying the sand layer and soil-cement piles for stabilizing the underlying clay. Post-treatment Standard Penetration Test (SPT) values indicated that DC significantly improved the sand layer (SPT rose to 15–25) while SCP effectively strengthened the clay (SPT increased to 8–12). The Tongi-to-Uttara section (CP01) simultaneously addressed liquefaction concerns and settlement issues through the integration of both techniques. Field verification confirmed that DC’s high-energy impact (10–23 ton pounders from 6 to 20 m height) and SCP’s displacement piles (∅700 mm) provided a cost-effective and time-efficientsolution for the dual-layer geotechnical issue. These results underscore the necessity of site-specific, stratified soil improvement methods in megaprojects built on diverse soft soils
The Distribution of A-Numbers of Hyperelliptic Curves in Characteristic Three
No full textIn this paper we present a new approach to counting the proportion of hyperelliptic curves of genus g defined over a finite field Fq with a given a-number. In characteristic three this method gives exact probabilities for curves of the form Y 2 = f(X) with f(X) ∈ Fq[X] monic and cubefree, probabilities that match the data presented by Cais et al. in previous work. These results are sufficient to derive precise estimates (in terms of q) for these probabilities when restricting to squarefree f. As a consequence, for positive integers a and g we show that the nonempty strata of the moduli space of hyperelliptic curves of genus g consisting of those curves with a-number a are of codimension 2a − 1. This contrasts with the analogous result for the moduli space of abelian varieties in which the codimensions of the strata are a(a + 1)/2. Finally, our results allow for an alternative heuristic conjecture to that of Cais et al.; one that matches the available data
Quantitative Comparison of Different Ultrasound Simulation Approaches for Civil Engineering Applications
No full textInterpreting ultrasonic waveforms is often challenging, especially in the presence of tilted boundaries that introduce multiple reflections, mode conversions, and echoes. To analyze such complex signal patterns, wavefield simulations provide a valuable tool. To ensure confidence in the simulation results, the accuracy of the numerical method is crucial. Another consideration when using simulations is their computational expense. Especially in civil engineering applications, large structures need to be investigated, which may not be feasible given the available resources. In this study, different numerical methods and software implementations commonly used for simulations in civil engineering are compared, including the Elastodynamic Finite Integration Technique (EFIT), the Finite Element Method (FEM), and the Spectral Element Method (SEM). The first simulation algorithm was implemented in Fortran by the first co-author; the second and third by utilizing COMSOL and Salvus, respectively. This comparison is conducted through three case studies. In the first case study, the simulation results are compared to analytically determined reflection and transmission coefficients for a two-layered material. Here, COMSOL and Salvus show lower errors than EFIT, but all simulation algorithms achieve relative errors \u3c 8%. In the second case study, simulated waveforms of reflections from a circular void (2D) are compared to an analytical solution. Simulations were performed for differently fine grids/meshes using identical hardware. The results demonstrate that both EFIT and COMSOL require longer run times to reach the same level of accuracy in the simulated waveforms as Salvus. The third case study shows that an ultrasonic echo array measurement in a PMMA block containing a void can be accurately simulated. However, due to hardware limitations, COMSOL was only able to perform a 2.5D simulation, and not a full 3D simulation. Salvus and EFIT reached similar accuracies in this case
The Gut Microbiota Shapes the Human and Murine Breath Volatilome
No full textThe gut microbiota is crucial to health, yet implementation of microbiota-based therapeutics is limited by the lack of rapid diagnostics. We hypothesize that breath contains gut microbe-derived volatile organic compounds (VOCs) reflecting microbiota composition and metabolism. In healthy children, we found that breath VOC composition (or volatilome), assessed by gas chromatography-mass spectrometry, correlates with gut microbiome composition and function. By capturing exhaled breath from human-stool-colonized and monocolonized gnotobiotic mice, we profiled breath VOCs and discovered that murine breath is also significantly influenced by the gut microbiome. VOCs from cultured gut microbes were identified in vivo in monocolonized gnotobiotic colonized mice. As a proof of principle, we demonstrated that exhaled breath predicts the abundance of a disease-associated bacterium, Eubacterium siraeum, in children with asthma. Altogether, our studies identify microbe-derived VOCs in breath, show that gut bacterial metabolism directly contributes to mammalian breath VOC profiles, and inform the development of non-invasive microbiome diagnostics
Microbial Communities and Biogeochemistry of a Melting Rocky Mountain Glacier
No full textMountain glaciers are disappearing rapidly, and with their disappearance, we may be losing unstudied biodiversity and genetic resources. A variety of habitats for microorganisms exist on glaciers, especially within pockets of supraglacial sediments (cryoconite) that support high levels of biological activity and diversity. We used biogeochemical approaches, high-throughput DNA sequencing, and microscopy to describe the biogeochemistry and microbial communities of supraglacial sediments on the Dinwoody Glacier in the Wind River Range, Wyoming. Carbon (C) and nitrogen (N) concentrations were high, and C:N ratios were close to the Redfield ratio indicating active nutrient cycling. We found unique microbial communities in sediments at different elevations on the glacier, with greater diversity near the terminus. Bacterial communities were dominated by photosynthetic cyanobacteria and numerous polymer-decomposing members of the Bacteroidetes. Eukaryotic communities were dominated by snow algae and ciliated protists among other predators and decomposers. DNA sequencing also yielded evidence of past eolian inputs of insect and plant materials including DNA from Orthoptera that may be remnants of locust swarms that were entombed in the glacier in the past. Overall, we found a robustly functioning ecosystem on Dinwoody Glacier with distinct supraglacial habitats and organisms that are rapidly disappearing due to human-induced climate change
Crossing Boundaries: Brachinites and Their Diverse Asteroidal Origins
No full textBrachinite meteorites are typically linked to the olivine-rich A-type asteroids. In this study, however, they appear to exhibit unexpected spectral diversity. Spectroscopic analysis of seven meteorites from the brachinite clan reveals two distinct populations in band parameters, overlapping with both the A-type and S-complex asteroids. This dual association shows that a single meteorite group can originate from multiple asteroid taxonomies. Notably, one S-complex-like specimen, Northwest Africa (NWA) 14,635, displays band parameters similar to those of asteroid (65803) Didymos, the target of the European Space Agency\u27s (ESA) ongoing Hera mission. These results underscore the value of spectroscopic characterization of poorly understood meteorite groups and identifying potential analogs that are highly relevant for current and future mission planning
Post-Wildfire Water Quality and Aquatic Ecosystem Response in the U.S. Pacific Northwest: Science and Monitoring Gaps
No full textAn increase in the occurrence of large, high severity wildfires in the western Pacific Northwest (PNW), USA, has created an urgent need for science to better inform forest management and policy decisions to maintain source water quality in the region. The western PNW faces similar challenges to other regions with shifting wildfire regimes and large population centers reliant on surface water from forested catchments. However, the uniquely wet and highly seasonal climate of the western PNW suggests that findings from other, more frequently burned regions may not be directly applicable. To identify science, monitoring, and management gaps and opportunities in the western PNW, this review was collaboratively undertaken by academics, non-government and industry representatives, and local, state, and federal government entities who have been working together since the 2020 Labor Day fires in Oregon. Focusing on Oregon and Washington, we found that monitoring networks for continuous water quantity and quality cover much of the state with greater representation in western U.S. ecoregions, but few studies have analyzed and published these data to capture and communicate the post-wildfire response. Approximately half of the streamgages in Oregon and Washington record major water quality parameters, and hundreds of sites in the area have discrete sampling for a wide range of water quality constituents. Still, numerous gaps exist in understanding the short- and long-term impacts of wildfire on hydrology, water chemistry, including pH and dissolved oxygen, mobilization of metals, aquatic ecosystems, and downstream drinking water treatment. Collective action to further collect, analyze, interpret, and publish the key data could help improve our understanding of post-wildfire water quality impacts in this and other increasingly wildfire-affected regions
Characterizing Indoor Surface VOC Contamination After the 2025 Los Angeles Fires
No full textWe quantify volatile organic compound (VOC) emissions from indoor surface swabs and portable air cleaner (PAC) filters collected in a home 30 days after the 2025 Los Angeles wildland-urban interface (WUI) fires. We calculate emissions for 17 fire-relevant compounds. Surface emissions exceeded those of clean controls, and emissions from a windowsill in a room without a PAC were ∼15× and ∼2× higher for benzene and toluene, respectively, than rates reported in the literature for comparable materials unaffected by smoke/soot. Particle filters installed in PACs at the start of the fire emitted aromatics at rates comparable to those reported in a study where filters operated for 200 days in a city. Emissions from activated carbon filters exceeded those of the particle filters tested as part of the present study by \u3e3×. A windowsill in a room without a PAC off-gassed more VOC mass than a windowsill in a room with a PAC, suggesting that air cleaners can reduce surface contamination. Modeling with benzene emission rates from impacted surfaces in a hypothetical indoor space resulted in a predicted indoor concentration ∼6× greater than outdoors. This study shows surfaces act as persistent VOC sources following WUI fires and indicates indoor surfaces affect exposure during and after fire events