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A Geothermal Amoeba Sets a New Upper Temperature Limit for Eukaryotes
No full textThe study of temperature limits has transformed our knowledge of the boundaries of life but has been largely focused on bacteria and archaea. We isolated a novel geothermal amoeba, , that divides at 63°C (145.4°F), establishing a new record for the upper temperature limit across all eukaryotes. We demonstrated cellular proliferation with growth experiments and visualized mitosis expansion microscopy. Using high-temperature live-cell imaging, we quantified movement up to 64°C. We assembled the genome of and using comparative genomics found an enrichment of genes related to proteostasis, genome stability, and sensing the external environment. Taken together, our findings challenge the current paradigm of temperature constraints on eukaryotic cells and reshape our understanding of where and how eukaryotic life can persist
Culture Clash: New Majority Students at PSU
No full textAt the heart of this open access book are nearly 100 interviews that the authors conducted with New Majority Portland State University undergraduates, especially first-generation students from immigrant families. These young adults have a lot to say about the practical and emotional challenges of balancing their warm cultures and extensive family obligations with college and classroom experiences that are often intimidating and impersonal. The book includes suggestions from the students and some of the faculty and staff they praised for how Portland State might become a place where many more feel at home and fulfill their dreams.https://pdxscholar.library.pdx.edu/pdxopen/1051/thumbnail.jp
Spike Timing Depended Plasticity Produces Unsupervised Learning of Synergistic Muscle Feedback in a Synthetical Neural Network
No full textThis study investigates how type Ia feedback from muscle spindles can be organized into groups representing agonistic muscle pairs through Spike Timing Dependent Plasticity (STDP). A single degree of freedom joint is actuated with four biologically modeled muscles forming two agonistic pairs. In order to emulate the sensory dynamics of biological muscle spindles, sensors in the model record the active length and velocity states of each muscle, the two primary factors eliciting type Ia afferent responses. In biological networks, synapses from Ia sensory neurons frequently activate interneurons representing agonistic muscle sources. This research investigates whether this organization can emerge in an initially unsorted network through synaptic modulation via STDP. The network of interconnected Ia sensory neurons and interneurons initiates with random conductance values, without knowledge of the desired organization structure. Under semi-randomized muscle activation, STDP in the proprioceptive network demonstrates the ability to organize Ia sensory neuron signals into groups according to their agonistic sources, mirroring known architecture. STDP provides a biologically plausible, unsupervised learning mechanism by which the known connections in vivo may form. With continuing work, STDP may prove itself capable of organizing proprioceptive networks for larger musculoskeletal systems, possibly on the scale of biological creatures. Future investigations will explore how the application of STDP to the other known synaptic connections in the Ia afferent network may assist in additional organization of the network architecture
Interdependence and Identity: Moral Relation in an Historical World
No full textThe twin concepts in the title will be introduced in the contexts of the philosophy of history and of philosophical personalism, as distinct from (though related to) their uses as logical and metaphysical categories. Overviews of varieties of philosophy of history and of basic principles I employ are foundations of the argument. Concepts, or ideas, in general have, I argue, real existence through the way that personal agents use them in creating the histories of human relations. I introduce a Personalist account, which has a more thoroughly diachronic character. Further remarks on the power of ideas to create relations expands this idea into the key claim: that urgency derived from interdependent human relations links historical and moral considerations. Interdependence and identity are then considered in terms of systems theory, notably biological autopoiesis and panpsychism. The value of all this appears in terms of relationships in moral life and, in conclusion, in an understanding of the connections between moral philosophy and philosophy of history
More Than Just a Criminal: Talking Back As a Critical Autoethnographic Journey
No full textThis article explores the experiences of doctoral students with criminal records navigating higher education, using a critical theoretical framework to highlight the unique challenges and triumphs I faced. Drawing upon decoloniality and critical race theory perspectives and activism, I define my critical scholarship as challenging the dominant oppression through thoughts and actions. Through autoethnographic and self-reflective narratives, I reflect on how my lived experiences as a Latino who has experienced criminalization. I have shaped my academic pursuits and critical consciousness. The autoethnography discusses systemic barriers such as stigma, discrimination, and institutional biases, showing how these obstacles have informed the author’s path toward becoming a critical scholar. Also, I examine my development of a critical position outside the formal doctoral program, highlighting the influence of personal, community, and activist experiences. By sharing my stories, I offer insights into the intentionality of higher education programs in addressing or perpetuating inequalities and the commonalities that unite system-impacted students. This emphasizes the importance of creating decolonized and just spaces within academia and the need for institutions to critically examine and transform their practices to support marginalized students. Offering this perspective will help students benefit from exercising agency to offer a counter-story to the dominant narrative
From Banking to Propagation: Expanding the Roles of a Seed Bank in a Changing Climate
No full textThe Rae Selling Berry Seed Bank at Portland State University is dedicated to preserving Oregon native plant genetic diversity, with an emphasis on rare species. It houses one of the nation\u27s oldest rare native seed collections which includes 28,000 accessions representing 800 taxa and millions of seeds. A conservation seed bank is intended to serve as a safeguard against the extinction of rare plant species by curating collected seeds from populations along maternal lines in long-term cold storage. The goal is to utilize the seed for reintroduction projects. However, in a changing climate, the question of how to reintroduce species with limited or absent germination knowledge becomes a paramount. To begin addressing this issue, the Rae Selling Berry has initiated a Native Plant Propagation Program which provides the community with supporting knowledge for conservation success of rare (and common) species. Since its inception in 2022, the Native Plant Propagation Program has conducted approximately 767 propagation trials on 564 species. Trials have tested various seed pretreatments (such as cold stratification or hormones) and have recorded the time required to produce plants in 4-inch containers. Seed bank staff have propagated 494 species using seeds, cuttings, or divisions and successfully produced 451 species in 4-inch containers; this is approximately 15% of Oregon\u27s native vascular plant flora. Plants propagated during trials were distributed to the public, including nearly 4,000 plants in 4-inch containers provided to 16 community groups. Here we discuss highlights from germination trials and provide recommendations on how to use the data
Enabling New Synthetic Platforms for Aryne Synthesis with Aryl Thianthrenium Reagents
No full textThe enormous importance of aromatic rings in organic molecules cannot be understated. Aromatic rings are present in the majority of pharmaceuticals, agrochemicals, and consumer products. The way in which these rings are arranged and substituted results in a molecule’s unique properties. Because of this, the current limitations of the chemical methods used to synthesize these molecules results in limited structural diversity and thus missed opportunities for the development of value-added products. To this end, this work demonstrates novel methods of aryne synthesis, aryl thianthrenium synthesis and a unique approach to structural scaffold hopping. The approaches presented herein allow for rapid access to structurally complex molecules.
Current methods of aryne synthesis either suffer from a lack of chemoselectivity or are costly and time intensive to synthesize. To improve access to aryne intermediates, we have developed a formal dehydrogenation of arenes that utilizes site-selective C-H thianthrenation or iodination to generate aryne precursors (Chapter 2). The generation of the aryne intermediate is then triggered by sodium tert-butoxide or lithium bis(trimethylsilyl)amide. This method’s numerous benefits over conventional methods of aryne generation are described.
Arene functionalization via C-H thianthrenation is limited to electron rich arenes. To overcome this limitation, electron-deficient potassium aryl trifluoroborates can be used in lieu of electron-rich arenes (Chapter 3). These reagents are easily accessible from commercially available aryl boronic acids or pinacol esters in a single step. In this study, we compare the reactivity of aryl boronic acids to potassium aryl trifluoroborates and demonstrate the synthetic utility of electron-deficient aryl thianthrenium salts for metal-catalyzed cross couplings and photoredox catalysis.
Finally, we present efforts toward the use of the formal dehydrogenation methodology reported herein as a valuable synthetic platform for molecular scaffold hopping (Chapter 4). Scaffold hopping methodology is demonstrated by the synthesis of a derivative of the popular beta-blocker Propranolol from a cheap simple arene in a single reaction vessel. Furthermore, this platform is shown to be useful for the synthesis of naphthalenes, naphthols and 1,4-naphthoquinones
Women\u27s Social Roles and Alcohol Use Among Military-Connected Spouses
No full textIncreases in women\u27s alcohol use are an intensifying public health problem in the United States, contributing to a hidden epidemic of alcohol-related mortality. Women\u27s alcohol consumption is often not openly discussed or recognized due to social stigma, the perception that women drink less than men, and the fact that women can experience negative health consequences from lower levels of alcohol consumption (relative to men), making the issue less visible than it actually is. A range of factors potentially influence women\u27s drinking, including social roles (i.e., mother); yet, the literature is varied as to whether the combination of multiple-role demands/expectations fosters reduced consumption or maladaptive coping with alcohol. Considering the past three decades have involved shifts in women\u27s social and cultural landscapes (i.e., workforce participation; delaying or abstaining from motherhood), contextual data on women\u27s alcohol use is needed to understand better how societal influences through role demands and expectations work to shape health behaviors. This dissertation explored women\u27s drinking behavior with a specific focus on multiple role strain (MRS) among women military-connected spouses, who are an under-researched population vulnerable to heightened experiences of role strain and embedded in a culture of high and problematic alcohol use.
Study 1 examined synchronous role strain from occupational, parental, and household roles (i.e., MRS) associated with alcohol use behavior as a function of distress and drinking to cope (DTC) motivation among National Guard service member spouses who are mothers. Results demonstrated that MRS predicted increased drinking frequency, quantity, and heavy episodic drinking through a serial pathway: increased distress followed by heightened DTC motives. A suppression analysis revealed that distress alone predicted decreased consumption, but DTC motivation emerged as the critical catalyst driving increased alcohol use despite role constraints, helping explain conflicting literature on whether role strain increases or decreases women\u27s drinking.
Study 2 provides a descriptive analysis of drinking patterns across social roles among women military-connected spouses using daily diary data. Three distinct role-based risk profiles emerged: employed childless women exhibited a high-risk profile with the greatest consumption and heavy episodic drinking rates with concentrated risk in social contexts; unemployed parents showed a moderate-to-high risk pattern where drinking is infrequent but intense when it occurs suggesting opportunistic or circumstance-driven risk; and employed parents demonstrated the most frequent participation in moderate drinking, highest solitary consumption and all solitary HED, yet (relative to other role categories) exhibits the lowest per-occasion consumption and HED rates in social contexts, suggesting a risk pattern hidden by social self-regulation and maintained role performance. Findings also revealed that daily monitoring captured more frequent and heavier consumption than retrospective reports, highlighting systematic underreporting in general surveys.
Study 3 tested whether daily role strain is associated with negative affect and motivates alcohol consumption using consecutive daily assessments. Contrary to the negative reinforcement model, women military-connected spouses consumed significantly less alcohol on high-stress days with elevated role strain and negative affect. Instead, women demonstrated strategic recreational drinking: concentrating consumption during low-stress weekend periods, timing drinking to precede days with minimal demands, and avoiding alcohol when circumstances required full functioning. However, average consumption per drinking occasion exceeds recommended limits for women, revealing a critical functionality-risk disconnect wherein maintained role performance may mask accumulating health risks.
Comprehensively, this research challenges dominant self-medication frameworks and reveals that drinking to cope motivation, rather than stress or distress alone, drives increased consumption among mothers experiencing role strain, while more generally, women managing multiple roles demonstrate sophisticated self-regulation by strategically timing consumption rather than drinking reactively to stress. These findings necessitate fundamental shifts in prevention and intervention approaches: moving beyond traditional stress-management programs to interventions that address the functionality-risk disconnect, challenge wine mom culture narratives, provide competence-affirming health risk education, and offer harm reduction strategies. This work provides empirical groundwork for building nuanced conceptual frameworks that illuminate promising pathways for developing targeted theoretical models of women\u27s alcohol use more generally. The distinctive patterns observed among military-connected spouses offer critical insights for gender-informed treatment models while highlighting broader implications for civilian women managing comparable high-stress multiple role demands
Northern Red-Legged Frog Use of a New Under-Road Crossing and Adjacent Upland Habitat (Lunch and Learn Presentation)
No full textA lunch and learn presentation to go deeper in depth on Alyson\u27s 2025 UERC presentation: A population of northern red-legged frogs (Rana aurora) located in northwest Portland must make a perilous crossing over U.S. Hwy 30 to access their breeding habitat in the floodplain of the Willamette River. To address the significant frog mortality that has historically resulted from this seasonal crossing, the Oregon Department of Fish and Wildlife managed the installation of an under-road crossing structure, completed in October 2024. To date, no studies have documented the effectiveness of crossing structures installed for R. aurora use, and few studies have examined their effectiveness for amphibians after installation. To meet these needs, our research will determine the efficacy of the structure for facilitating the migration of red-legged frogs between their lowland and upland habitats by combining the use of passive camera monitoring, PIT tagging, radio tracking and upland habitat analysis, in collaboration with partners at Oregon Metro, ODFW and USGS. Our study aims to investigate structure use as a mechanism for improved habitat connectivity for R. aurora and other species, a key issue for wildlife managers identified in the Oregon Conservation Strategy (OCS), while simultaneously informing management for an OCS species. This presentation will outline our study objectives, predictions and hypotheses, describe ongoing field methods, and share our preliminary findings from the first frog migration following structure installation, with the goal of generating valuable discussion about amphibian movement and habitat connectivity in urban ecosystems
HPV Prevention in Men: A Narrative Review of Strategies, Risks, and Public Health Implications
No full textHuman papillomavirus (HPV) is the most common sexually transmitted infection worldwide, impacting both males and females. In men, HPV causes genital warts, more than 90% of anal cancers, and 60% of oropharyngeal cancers. Given that one in three men are infected with HPV worldwide, there is a pressing need for enhanced public health strategies focusing on prevention. This comprehensive narrative review presents an overview of HPV in men, key risk factors, and primary prevention in men. The most effective preventive measure for HPV in males is vaccination. Males at high risk for HPV include those who smoke, have human immunodeficiency virus, consume alcohol, engage with multiple sexual partners, fail to use barrier methods, and are unvaccinated. HPV vaccinations prevent most HPV-associated diseases; however, numerous barriers to vaccine uptake remain, including misconceptions that men do not benefit from vaccination, safety concerns, limited accessibility, and inconsistent vaccine recommendations