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Recent Submissions

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    Temporal misalignment of renal sodium transport promotes non-dipping blood presure phenotypes
    (Public Library of Science (PLOS), 2026-08-13) Layton, Anita T.
    Non-dipping blood pressure (BP) phenotypes are strongly associated with cardiovascular and renal morbidity, yet the physiological mechanisms governing nocturnal BP dipping remain incompletely understood. Experimental evidence suggests important roles for circadian timing, renal sodium handling, autonomic regulation, and sleep-wake behavior, but their interactions are difficult to isolate experimentally. We developed an integrated circadian-sleep/wake computational model of long-term BP regulation incorporating rhythmic modulation of renal sympathetic nervous activity, vascular tone, renin-angiotensin-aldosterone signaling, tubular sodium transport, and behavioral sleep-wake influences. The model reproduced a physiologically realistic healthy dipper phenotype with robust nocturnal BP reduction and daytime-predominant natriuresis. Component analyses demonstrated that vascular rhythmicity and sleep-wake modulation were dominant determinants of BP dipping, whereas intrinsic tubular sodium transport rhythmically redistributed natriuresis toward the nighttime period with modest effects on BP dipping. In contrast, altering the phase of tubular sodium transport produced marked effects on both natriuresis timing and BP regulation. Delayed tubular sodium transport phases shifted sodium excretion toward the nighttime period and converted the model from a dipper to a non-dipper phenotype despite preservation of rhythmic oscillations in other physiological systems. Sodium loading and enhanced salt-sensitive tubular sodium reabsorption amplified vulnerability when tubular sodium timing was delayed. These simulations suggest that physiological BP dipping emerges from coordinated temporal interactions among cardiovascular, renal, and behavioral regulatory systems. Non-dipping behavior may therefore arise not only from impaired rhythmicity, but also from misalignment among otherwise preserved physiological oscillators, particularly under sodium-loaded and salt-sensitive conditions.
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    Environemental impacts of laboratory and scientific equipment: Focus on equipment operation and procurement
    (Public Library of Science (PLOS), 2026-08-20) Cimprich, Alexander; Kasaeipour, Sahand; Young, Steven B.
    Climate change and environmental sustainability are major priorities across scientific and policy domains. Scientists themselves are starting to recognize that their own activities have direct and indirect environmental impacts. These impacts result from things like material and energy use and waste generation in conducting scientific research, particularly in laboratories. In this article, we build upon growing efforts to measure and manage these environmental impacts by conducting cradle-to-grave life cycle assessments (LCAs) of widely used scientific and laboratory equipment. We considered over 3000 pieces of equipment used by Government of Canada laboratories. Our study contributes in four ways. First, although previous work has examined laboratory consumables and other impact drivers like building energy consumption and transportation, our study draws attention to the environmental impacts of laboratory and scientific equipment. Second, our study demonstrates a novel approach for screening large and varied sets of equipment-level LCA results to sustainability transformations by highlighting leverage points informed by the life cycle profile of equipment. Our results suggest a tendency for laboratory and scientific equipment to be use-intensive (as seen, e.g., in the case of refrigerators and freezers where the use stage accounts for approximately 97% of life cycle GHG emissions). However, this life cycle profile varies across environmental indicators (e.g., climate change, acidification, smog formation, and ecological toxicity) and with changes in equipment usage frequency (i.e., hours per year in operation). Some equipment, like scanning electron microscopes, can be production-intensive. These findings suggest that sustainability transformations for laboratory equipment need to consider the life cycle profile of the equipment and involve leverage points beyond procurement decisions.
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    Reciprocity in global health: How successes from the global south can inform global health interventions in Canada and the U.S.
    (Public Library of Science (PLOS), 2026-08-27) Masvawure, Tsitsi B.; Ndu, Mary; Oga-Omenka, Charity
    Global health has traditionally functioned as a project of high-income countries (HICs) addressing health challenges in low- and middle-income countries (LMICs). This "outward facing" orientation has created conceptual and operational boundaries that obscure the persistence of health inequities within HICs and perpetuates the false assumption that resource-rich nations have resolved fundamental health equity challenges in their own countries. In this essay we argue that HICs have global health problems of their own and should be considered legitimate sites for global health intervention. We propose an approach to doing global health in the global north that is based on reciprocal learning and where solutions to global health problems can also be found outside the borders of HICs. Complementing the extant scholarship on the need to decolonize global health, this essay highlights LMIC-led successes that can inform global health practice in the U.S. and Canada thus positioning global health as a truly egalitarian project.
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    Theta burst stimulation of the visual cortex does not alter contrast sensitivity under optically induced blur
    (Public Library of Science (PLOS), 2026-09-01) Wong, Crystal Suei Cheng; Tan, Ken Wei Sheng; Li, Tingni; Gaultney, Linden; Thompson, Benjamin; Leung, Tsz Wing; Park, Adela So Yun
    This study investigated whether a single session of repetitive transcranial magnetic stimulation (TMS), specifically theta burst stimulation (TBS), acutely modulates visual function under conditions of induced optical defocus. Twelve adults with normal or corrected-to-normal vision participated in a pre-registered, within-subject, double-blind, sham-controlled study. Participants first adapted to an experimentally induced + 1.50D optical blur for 10 minutes. Following this, stimulation was applied to the primary visual cortex according to a pre-randomised allocation. Stimulation consisted of continuous TBS (cTBS), intermittent TBS (iTBS), or sham stimulation, with each condition applied to all participants over separate visits. Visual acuity (VA) and contrast discrimination thresholds were measured under the induced blur condition immediately before and after stimulation. Repeated measures ANOVA revealed no significant interaction between stimulation condition and time for either contrast discrimination threshold (F(2,22) = 0.03, p = 0.96, partial ηp² = 0.003) or VA (F(2,22) = 0.12, p = 0.88, partial ηp² = 0.011). Although a significant main effect of time was observed for VA (F(1,11) = 6.30, p = 0.029, partial ηp² = 0.364), reflecting an improvement across all conditions, there were no differential effects attributable to active cTBS or iTBS compared to sham. Consequently, a single session of TBS applied to the visual cortex did not result in a measurable modulation of visual performance under acute optical defocus in adults with typical vision. Rapid homeostatic mechanisms activated during short-term blur adaptation may reduce the susceptibility of the visual cortex to the acute effects of TBS.
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    Validating a novel measure of scientists' disciplinary affiliation that captures its complexity and plasticity
    (Public Library of Science (PLOS), 2026-08-26) Pizzo, Gina Marie; McCright, Aaron M.; Gonnerman, Chad; Hall, Troy E.; Plaisance, Kathryn S.; Robinson, Brian
    Much research since the 1950s has investigated scientists’ views and behaviors. Employing data from standardized surveys, researchers often analyze how such views and behaviors vary across scientific disciplines. The results of these efforts are likely influenced by the quality of the survey instrument(s) used to measure scientists’ discipline or “disciplinary affiliation” as well as the size and quality of respondent samples. Even though disciplinary affiliation is a complex, multi-dimensional construct, most surveys over the years include only a single nominal indicator of one dimension (e.g., the discipline of respondents’ highest degree, current department, or self-identity). Only using a nominal indicator—with respondents placing themselves into distinct disciplines assumed to be internally homogeneous—limits our ability to measure variation in their disciplinary affiliation within nominal disciplines. We refer to this variation, or plasticity, in scientists’ disciplinary affiliation as disciplinarity, or the extent to which their affiliation may vary along a continuum between strong connection to their discipline’s core to broader association with their discipline’s frontier—possibly leading to boundary transgression and eventual affiliation with a different nominal discipline. We created a multi-dimensional continuous measure of disciplinarity for use in tandem with a categorical disciplinary affiliation indicator (i.e., discipline of PhD degree) to capture this variation. We included both measures in a standardized survey on scientists’ views about the nature of science and experiences in cross-disciplinary research that we administered to a large sample of 4,113 tenure-system science faculty at 83 US research universities. After offering narrative evidence of the content validity of our novel five-dimension disciplinarity instrument, we provide statistical evidence that our resulting disciplinarity scale has construct, convergent, and concurrent criterion validity for measuring the complexity and plasticity of scientists’ disciplinary affiliation. We close with suggestions for how other researchers may employ this novel instrument for their own purposes.