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The Lewis Basicity of Amines on the Legault Iodonium Lewis Acidity Scale.
No full textDiaryliodonium-amine complexes are proposed as key intermediates in metal-free C-N coupling reactions. Herein, H NMR titration is used to quantify association constants () between diaryliodonium triflates and synthetically relevant amines from which the amine Lewis basicity (LB) parameter is calculated. Compared to anionic Lewis bases, distinct solvent effects are observed
Sunrise at the Salton Sea: Environmental Justice, Land Use Change, and Hydrosocial Dynamics of Solar Energy Transitions in the Imperial Valley, California
No full textCalifornia\u27s Imperial Valley, with lithium-rich geothermal brines, extensive flat agricultural fields with abundant desert sunshine, and access to transmission lines, is a leading case to explore interconnected themes around just energy transitions. Despite being the poorest county in California and one of the smallest, Imperial already provides 15% of the state’s solar electricity, and the region as a whole represents on the order of 25% of the state’s electric power capacity. This paper brings to light frictions over solar energy development that have emerged over the history of solar power development in the southern Salton Sea region. It describes the history of solar development in the county and contextualizes in the broader hydrosocial territory and political economy, including how energy development patterns in the region are connected to regional and global energy markets. The analysis is based on analysis of media and news articles, public comments to official proceedings, hearings to environmental review or similar processes, and interviews, and involves a case study tracked closely since 2008. The findings show how social resistance to solar projects can result in better land use outcomes, but also points to different types of hydrosocial reconfigurations and environmental justice issues facing rural communities within and beyond the region. In the arid western United States, solar energy development is mediated by disputes over of Colorado River water, tribal sovereignty and cultural resources, raising questions about how new enterprises can finance ecological restoration of the degraded Salton Sea
Global Scale Assessment of the Human-Induced Extinction Crisis of Terrestrial Carnivores.
No full textHuman impacts on carnivores are a persistent conservation challenge worldwide. We present a global analysis showing the overlap of conservation lands and the cumulative impact of humans on the distribution ranges of 257 terrestrial carnivore species. Our findings reveal that 64% of carnivore ranges overlap with areas characterized by high human pressures. We found that Indigenous peoples\u27 lands emerge as crucial for carnivore population viability, potentially safeguarding 26% of carnivore ranges globally, while protected and wilderness areas cover roughly 10 and 16% of carnivore ranges, respectively. These three areas combined cover 35% of the global range of carnivores. Reducing human pressure on conservation lands and managing them to protect carnivores are therefore critical, yet challenging. The extent of carnivore ranges outside these areas underscores the necessity to expand the network of conservation lands, which are a pivotal component of global conservation planning, alongside broader proactive species-specific conservation measures
Detecting and Analyzing Frequency Events in Power Systems Using Tunable Parameters-Based Algorithms: Development, Optimization, and Analysis
No full textThe rapid growth in the integration of renewable energy sources into power grids has driven a transition from conventional thermal-based generation to inverter-based resources. As a result, power system inertia has decreased, and the rate of change of frequency has increased. This presents a challenge for frequency stability in modern power systems.
Power systems disturbances, such as significant faults or major disruptions in generation or load, cause imbalances between power supply and demand, which may result in severe frequency fluctuations known as frequency events. Following such events, fast frequency response is needed to provide frequency support and prevent system collapse. Therefore, monitoring and detecting frequency events promptly and accurately is critical to stabilizing power systems.
This dissertation addresses the challenge of detecting frequency events in diverse power systems by enhancing existing frequency event detection methods through detection process modifications and developing unique tunable parameters. Since system characteristics differ across regions, frequency event detection algorithms must be customized by domain experts for each balancing area using tunable parameters. By optimizing these parameters for specific power system, the algorithms can accurately detect frequency events and can also be used for further analysis to determine trends in frequency events over time, ensuring system stability.
This dissertation focuses on the enhancement and optimization of frequency event detection algorithms. These detection algorithms are compared with other state-of-the-art frequency detection methods. The study examines the impact of signal denoising techniques on detection accuracy, analyzes frequency performance over time, reviews global frequency performance standards, and conducts comprehensive sensitivity analyses.
The five primary contributions of this dissertation are: the development of frequency event detection algorithms with tunable parameters for specific balancing areas; optimization of the developed algorithms parameters to enhance results and adaptability, conducting a comprehensive analysis of signal denoising methods and their impact on frequency event detection; the proposal of criteria-based tunable parameters to assess frequency events trends and severity; presentation of an enhanced understanding of global frequency performance standards; and deeper insights into frequency specifications across diverse power systems
Assessing The Accessibility Of Queer Romance Book Covers As Digital Thumbnails: An Analysis Of Color Contrast, Colorblind Safety, And Typography Legibility
No full textThis research investigates the digital accessibility of queer romance book covers displayed as thumbnails online, focusing on the balance between creative freedom, genre appeal, and inclusive cover design. Using a dataset of 100 highest-rated queer romance titles from Goodreads (2020–2024), the study evaluates accessibility by examining color contrast ratios against Web Content Accessibility Guidelines (WCAG) standards, assessing colorblind safe design with Adobe Color, and measuring typography legibility through a custom-developed scale. Findings reveal that many covers fall short of WCAG color contrast requirements, yet a majority are colorblind safe, indicating that relatively minor design adjustments can significantly improve digital accessibility at thumbnail size without sacrificing visual identity. This paper argues that integrating digital accessibility into cover design—through WCAG-compliant color contrast, colorblind safe palettes, and clear typography—supports rather than limits genre appeal and creative expression. By prioritizing accessibility, publishers and designers can expand readership, improve discoverability in digital marketplaces, and unlock new market opportunities within queer romance
The Hydro-Geomorphic Response of the Ephemeral Lower Nahal Tzalmon Stream to Experimental Flow Releases Towards Replenishment of the Sea of Galilee, NE Israel
No full textStudy region:
The Sea of Galilee’s western watershed includes the Lower and Upper Galilee subregions in northern Israel. Nahal Tzalmon stream (110 km2) is one of the major gravel-bed channels draining those subregions into the lake. Study focus: The study focus was to monitor the immediate effects of introducing “hungry water” from the newly mega-project of the “Reverse National Water Carrier” (RNWC). The project was designed to convey desalinated water from the Mediterranean coastal desalination plants through a 5 km open channel into the lower Nahal Tzalmon stream in order to replenish the Sea of Galilee. During a 2-day experimental flow releases with three different peak flow discharges, the hydrologic and geomorphic outcomes were documented. New hydrological insights for the region: The three flow releases showed significant discharge attenuation (67–39 %) due to the large transmission losses over a dry bed (91 %) that was significantly reduced when the alluvium was moist (52 %) or wet (30 %). The suspended sediment concentrations and yields were low compared to natural flow events but also when compared to other Mediterranean streams. Bedload transport under the hydrological conditions of the experiment did not cause a major disruption to the armored channel bed. A conceptual model is proposed for the new hydrologic-geomorphic conditions the RNWC offers for channel restoration, making the stream a prominent perennial tributary to the Sea of Galilee
Complete Genome Sequence of Saccharolobus Solfataricus Strain S441, from Lassen Volcanic National Park
No full textHere, we present the complete genome sequence Saccharolobus solfataricus strain S441, isolated from Devil’s Kitchen, Lassen Volcanic National Park in Northern California, U.S.A. The genome for this strain is 2,766,550 base pairs, with a GC content of 35.7% and 3,031 genes
History’s Movement: The Historical Ontology in Social Ontology
No full textSocial ontology and the philosophy of history both concern themselves with human collectives. Social ontology is supposed to be theoretical, although the social sciences are supposed to be empirical. Philosophy of history is supposed to be theoretical, although historiography is supposed to be empirical. In fact, the a priori and the a posteriori mix in both theoretical and empirical endeavors in similar ways. Since the two endeavors hold part of their objects of inquiry in common, they should be able to speak to another. In what follows I aim to expose some of the ways their dialogue stresses and can nourish them both. Critical social ontology can enhance the moral purchase of social ontology. Re-conceiving ontology for social ontology must rely on developing an orientation toward diachronesis and history
Evaluating Gains in Student Self-Efficacy in Scientific Literacy Associated with a Brief Curricular Intervention
No full textUndergraduate research experiences (UREs) are high-impact practices that enhance retention, motivation, and self-efficacy in science, particularly for students with limited prior exposure to scientific environments. However, many students-especially those from underrepresented or marginalized backgrounds-enter these experiences with low research self-efficacy, stemming from limited familiarity with academic language, scientific literature, and research communication. The Research Induction Curriculum (RIC) was designed to address this challenge by providing early, structured training in scientific literacy through scaffolded journal club discussions. The RIC introduces students to progressively more complex scientific articles, supports peer discussion, and builds confidence in reading, interpreting, and presenting scientific information. This study investigates two research questions: (i) how does students\u27 self-perceived self-efficacy in scientific literacy change after completing the RIC? and (ii) are perceptions of these gains dependent on when the assessment is conducted? A total of 91 students in the National Institutes of Health (NIH)-funded Building Infrastructure Leading to Diversity (BUILD) Enhancing Cross-disciplinary Infrastructure and Training at Oregon (EXITO) program at Portland State University completed surveys either immediately before and after the RIC (prospective pre-post design) or nearly 1 year later (retrospective pre-post design), after participating in mentored research placements. While both groups demonstrated gains in their confidence after participating in the RIC, students assessed retrospectively reported significantly greater confidence gains than those assessed prospectively. This study highlights the benefits of a brief intervention in preparing students for UREs as well as the influence of evaluation timing and authentic research experience on students\u27 perceptions of growth
Evaluation of User Interactions and Preferences of Shared Bicycle and Pedestrian Transit Platforms
No full textShared bike and bus platforms have been deployed in an effort to minimize conflicts between bicycles and buses (and other motor vehicles) on streets with bike lanes and bus transit service. This paper assesses bicycle/micromobility user and pedestrian behavior in shared bicycle and transit platforms along a bus rapid transit corridor in Portland, OR. Research objectives include understanding interactions between these users and potential conflicts between people on foot (or wheelchair/mobility devices) who are waiting for, boarding, and/or alighting a bus and people on bicycles riding in the bike lane. The research also assessed how well the shared transit platforms are working for the visually impaired. The mixed methods approach included video observation of eight platforms (272 h for bicycle/micromobility users; 80 h for transit riders/pedestrians), intercept surveys of transit riders, and interviews of riders experiencing disabilities. Only 2% of bicyclists and other micromobility users (23 out of 1,059 observed) used motor vehicle travel lanes to move past buses, suggesting that the effort to minimize bike and bus conflicts is largely successful. Although bicyclists and other micromobility users rarely stopped for pedestrians in platform areas, they did travel more slowly when buses and transit riders were present. Given the volumes observed, bicycle and micromobility users and transit riders seem to be managing their interactions with few conflicts. However, it is important to note that observed bicycle volumes were low, and transit platforms were rarely crowded during the observed time periods