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Golden Ratio Function: Similarity Fields in the Vector Space
No full textIn this work, we generalize and describe the golden ratio in multi-dimensional vector spaces. We also introduce the concept of the law of similarity for multidimensional vectors. Initially, the law of similarity was derived for one-dimensional vectors. Although it operated with the values of the ratio of the parts of the whole, it created linear dimensions (a line is one-dimensional). The presented concept of the general golden ratio (GGR) for the vectors in a multidimensional space is described in detail with equations. It is shown that the GGR is a function of one or more angles, which is the solution to the golden equation described in this work. The main properties of the GGR are described, with illustrative examples. We introduce and discuss the concept of the golden pair of vectors, as well as the concept of a set of similarities for a given vector. We present our vision on the theory of the golden ratio for triangles and describe similarity triangles in detail and with illustrative examples.Electrical and Computer Engineerin
Impact of Early Cretaceous Oceanic Anoxia on Carbonate Platforms From the Gargano Promontory, Italy
Get PDFCarbonate rock series withing the Gargano promontory preserve the record of carbonate platform evolution during the Early Cretaceous. Previous works reported on the evidence of global oceanic anoxia driven by a warmer climate and marine volcanism is present in these layers, as evidenced by large shifts in isotope geochemical signatures, and the destabilization/ local extinction of faunal groups. In particular major and minor changes in carbon isotope composition of carbonates help identify the OAE1a within Aptian sequences.
The goal of this study is to better understand the evolution of carbonate-producing ecosystems during this period of instability within the Gargano Promontory. Different lithographic columns are considered to better understand the timing and intensity of the impact of the OAE1a regionally. To identify the OAE1a signal in multiple localities we aim at documenting strong negative shifts in δ¹³C values as well as the changeover in fossil content within the carbonate platform. Moreover X-Ray Fluorescence geochemical data permit to to trace periods of paleoenvironmental instability when nutrient and/or detrital input changed.
Lithographic column, geochemistry and microfossil content show subdivisions of the carbon isotope record at Borgo Cerano and San Giovanni Retondo that includes major and minor fluctuations labeled C1-C11, following Menegatti et al. (1998). A sharp decline in local faunas associated with a strong negative spike (C3) and a positive pulse (C4) in δ13Cvalues, is paired with an expansion of opportunistic Chondrodonta populations. This period is followed by a relatively fast recovery period of benthic ecosystems, that was associated with warmer, meteoric conditions and low sea level, interpreted from the formation of dolomites at the top of samples at Borgo Cerano and sharp increases of magnesium content at both San Giovanni Rotondo and Borgo Cerano localities.
Carbon isotope segments C3-C5 are associated with regional and global anoxia, preceding continuing directly before and after the sharp negative pulse of C13, associated with the OAE1a. Comparing the assumed placement of carbonate sections in Glore 2025 and Carmona 2023 to Frijia, Morsilli and Suarez’s data helps to chronologically place the deposition in both SR and BC sections. Changes in fossil content is also used to determine placement of the OAE1a, shown by the appearance and expansion of Chodrondota and Bacinella-Lithocodium after a dramatic reduction of fauna has taken place, suggesting a niche vacuum was created during this period. Both of these lines of evidence, including the isotopic evidence of a negative carbon 13 spike and increasing magnesium in samples, shows a warming and anoxic environment at this time.Earth and Planetary Science
Investigating the Antimicrobial Properties of Local and Model Algal Species Through Chemical Extraction and LC-MS Profiling
Get PDFTo meet the increasing demand for new antimicrobial therapeutics against increasingly resistant strains of pathogenic microbes, the rich metabolic profiles of microalgae represent a promising, underexplored reservoir of chemical species with the potential to bypass current resistance mechanisms. The present study explores the antimicrobial activity of marine and freshwater algae, specifically concentrating on a Central Texas strain of the filamentous Spirogyra algae, along with other lab-grown genera (Cladophora and Mougeotia), as scalable sources of secondary metabolites with antibiotic properties. This project aimed to contribute to the developing body of literature surrounding algae-based solutions to the antimicrobial resistance (AMR) crisis. After culturing and preparation, chemical extraction was performed on algal samples using a four-solvent system of comprehensive polarities. Disc diffusion procedures were then performed using the resulting extracts rich in secondary metabolites. Lastly, Zones of Inhibition (ZOIs) were measured as an indication of antimicrobial activity against four ESKAPE pathogens/surrogates. Results demonstrated the superiority of acetonitrile and methanol in solvent efficiency accross all genera; these extracts from the local Spirogyra strain demonstrated significant activity against two Gram Positive pathogens. Moreover, acetonitrile and methanolic extracts consistently yielded the most frequent and largest ZOI sizes, establishing themselves as the most effective extraction solvents for the genera studied. While extracts from the locally sourced Spirogyra exhibited activity restricted only to Gram Positive strains, Cladophora and Mougeotia demonstrated broader efficacy, inhibiting both Gram-positive and Gram-negative targets. This project is ongoing, with current work focusing on fractionating active extracts for Liquid Chromatography-Mass Spectrometry (LC-MS) analysis to structurally characterize all metabolites responsible for the observed antimicrobial phenotypes.Biology, Health and the Environmen
From Search Engines to AI Overviews: A Comparative Study of Web Content Discovery
Get PDFAdvancements in Artificial Intelligence are transforming how information is delivered in search environments by incorporating synthesized AI overviews alongside traditional SERP listings. Unlike conventional retrieval algorithms that return indexed website links, AI Overviews generate integrated summaries derived from multiple web sources, reshaping the user’s informational experience and raising new challenges for platforms, SEO strategies, and digital information ecosystems.
Drawing from Media Richness Theory and Media Synchronicity Theory, this three-essay research investigates the extent, drivers, and consequences of divergence between AI Overviews and traditional search results. The first essay examines whether AI-generated results differ from SERP listings in terms of content selection and source overlap. Findings from 131 travel-related queries show an average URL overlap of only ~11%, indicating that AI-generated summaries draw from a comparably distinct source base.
The second essay applies Media Synchronicity Theory to explore why this divergence arises. Linguistic and structural analyses—including lexical diversity, cluster entropy, noun diversity, Gini index, and text-to-HTML ratio—reveal a consistent pattern: AI Overviews favor convergence-oriented communication marked by cohesion and semantic focus, whereas SERP results support conveyance-oriented exploration through broader, more varied sourcing.
The third essay examines how different display formats shape cognitive processing outcomes. Using a between-subjects experimental design, participants were exposed to either AI-generated overviews, traditional SERP results, or a hybrid display. Results show that AI Overviews increase processing fluency, which reduces psychological distance and produces higher satisfaction and decision readiness. These findings suggest that AI functions not merely as an informational overlay, but as a cognitive restructuring mechanism that alters how users mentally engage with search-based information.
Collectively, this work advances theoretical understanding of AI-mediated information environments and offers practical implications for search platform design, content strategy, and the future of digital knowledge access.Information Systems and Cyber Securit
A Lyapunov-Based Analysis on the Almost Periodicity of Impulsive Conformable Reaction–Diffusion Neural Networks with Distributed Delays
Get PDFThe focus of this research is the qualitative behavior of a reaction–diffusion neural network with distributed delays and conformable derivatives under impulsive perturbations. In particular, the almost periodic behavior of the proposed model is studied using a Lyapunov-based approach. By constructing an appropriate Lyapunov-type function, criteria that guarantee the existence and uniqueness of an almost periodic state are provided. The established criteria extend a few existing results on the almost periodicity of conformable models and contribute to the development of the field. In addition, the notion of global conformable exponential stability is introduced and analyzed for the developed model. A suitable example is discussed
Additive Manufacturing of 6061 Aluminum by Filament Based Material Extrusion (MEX): Process Development and Mechanical Characterization
Get PDFThis work examines how feedstock composition and process settings influence the performance of Al-6061 parts made through material extrusion (MEX). A feedstock with 57 vol% (78 wt%) solids loading was selected based on torque rheometry, showing stable flow and shear-thinning behavior with a measured viscosity of 710.9 ± 3.2 Pa·s. Filaments produced from this material had a consistent diameter of 1.74 ± 0.0064 mm and were used to print specimens at extrusion multipliers of 0.9, 0.95, and 1.0. Debinding and sintering procedures, guided by thermal analysis, resulted in a peak density over 97% of the theoretical value. Among the conditions tested, the 0.95 extrusion multiplier produced the most favorable mechanical properties, with an ultimate tensile strength of 153.5 ± 3 MPa, a yield strength of 68.2 ± 11.7 MPa, and elongation reaching 28 ± 3%, which aligns with values reported for annealed Al-6061. Fractographic analysis showed a ductile fracture mode, confirming good interlayer adhesion and consistent sintering. These results show that MEX is a reliable method for fabricating Al-6061 parts with complex geometries and stable mechanical performance
COVID-19 Oral Historias Project: Amplifying the Lived Experiences of San Antonio’s Hispanic Community
Get PDFThrough a series of over 100 bilingual interviews with Hispanic San Antonians, the COVID-19 Oral Historias Project documents the Latino/a/e community’s experiences through the pandemic by sharing individual stories, amplifying local voices, and creating compassion in a fragmented time. The present article documents the project itself, contextualizing its creation, detailing its methodology, highlighting the most common themes across interviews, and pointing out its novel contributions. While the interviewees’ experiences are inarguably diverse, narrative threads were found throughout the corpus, united by the duality of the narrators’ experiences; throughout this period, they simultaneously negotiated community norms and official health directives, local and international anxieties, and hopelessness and hope. The project is unique in (1) its language use, privileging minoritized ways of speaking (Spanish and Spanglish); (2) its size, with over 100 interviews; and (3) its clearly delimited scope, with all respondents living in San Antonio. This massive, unified resource creates a public collection of bilingual stories, highlighting non-hegemonic voices that are of value to the community itself, as well as to the recorded history of the pandemic, filling in historical gaps and providing real, lived accounts of this period that might otherwise be lost over time
Impact of Polyunsaturated Fatty Acid Structure on the Induction of Tau Aggregates
Get PDFTau aggregation is one of the main hallmarks of Alzheimer’s disease, and can lead to neuronal death. Finding tau aggregation inhibitors are vital for therapeutic treatments but have so far been unsuccessful. An important aspect of in vitro studies of tau is generating structures of filaments that replicate what is found in AD. Tau does not spontaneously aggregate and in vitro needs the presence of a cofactor to polymerize. One potential way to induce tau aggregation is with the use of polyunsaturated fatty acids (PUFAs) such as arachidonic acid. Thirteen different PUFAs will be used to determine if the carbon chain length or number of double bonds can be used to identify patterns of how the PUFA will impact tau aggregation. This can give insight into which PUFAs are potentially making similar or different tau fibril structures. Filaments induced by PUFAs that produce different aggregation patterns will be analyzed through cryo-electron microscopy (Cryo-EM) to determine if AD relevant structures are being produced.
Results showed that the structure of the PUFA does not seem to impact the aggregation patterns. Instead two patterns arose, in which one aggregation continues to increase as concentration of the PUFA increases. The other aggregation increases up to a certain concentration before declining. Utilizing Cryo-EM on filaments induced by PUFAs belonging to different patterns was unsuccessful as the resulting aggregates lacked a twist making it difficult to solve for the molecular structure and unable to determine if disease relevant structures are made by PUFAs.Neuroscience, Developmental and Regenerative Biolog
Archive of Blood and History: Finding Identity Through Gothic Archival Work
Get PDFThe purpose of this study is to explore the relationship between our identity and the archive through a fictional lens. Inspired by those stories that are often lost or silenced, this creative project highlights the grievances of unknowing oneself in relation to our past and tackles what it means to decipher the pieces that make up who we are. In applying a Theory in the Flesh perspective, I analyze the significance of having access to information, and how it drives us to make changes within our environments. I showcase these perspectives through forging together Gothic Fantasy and Latinx archival techniques, genres that both heavily rely on documentation to tell a story. By integrating these elements, this creative display intends to speak upon how we interpret ourselves due to our relationship with our history, how the act of documenting stories leads to knowing oneself, and how the darkest parts of our past often shape our perspectives. In working through my own story through a fictional lens, I attempt showcase the nuance, difficulty and significance of unlearning the patterns others have woven before us to create something new.Englis
Toward Designing Accessible and Meaningful Software for Cancer Survivors
Get PDFCancer survivors experience a wide range of impairments arising from cancer or its treatment, such as chemo brain, visual impairments, and physical impairments. These impairments degrade their quality of life and potentially make software use more challenging for them. However, there has been limited research on designing accessible software for cancer survivors, despite the rich literature on CSCW technologies for cancer survivors. To bridge this research gap, we conducted a formative study including a survey (n=46), semi-structured interviews (n=20), and a diary study (n=10) with cancer survivors. Our results revealed a wide range of impairments experienced by cancer survivors, including chemo brain, neuropathy, and visual impairments. Cancer survivors heavily relied on software for socialization, health purposes, and cancer advocacy, but their impairments made software use more challenging for them. Based on the results, we offer a set of accessibility guidelines that software designers can utilize when creating applications for cancer survivors. Further, we suggest design features for inclusion, such as health resources, socialization tools, and games, tailored to the needs of cancer survivors. This research aims to spotlight cancer survivors' software accessibility challenges and software needs and invite more research in this important yet under-investigated domain.Information Systems and Cyber Securit