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Characterizing PM2.5 Emissions and Temporal Evolution of Organic Composition from Incense Burning in a California Residence
Get PDFThe chemical composition of incense-generated organic aerosol in residential indoor air has received limited attention in Western literature. In this study, we conducted incense burning experiments in a single-family California residence during vacancy. We report the chemical composition of organic fine particulate matter (PM2.5), associated emission factors (EFs), and gas-particle phase partitioning for indoor semivolatile organic compounds (SVOCs). Speciated organic PM2.5 measurements were made using two-dimensional gas chromatography coupled with high-resolution time-of-flight mass spectrometry (GC×GC-HR-ToF-MS) and semivolatile thermal desorption aerosol gas chromatography (SV-TAG). Organic PM2.5 EFs ranged from 7 to 31 mg g-1 for burned incense and were largely comprised of polar and oxygenated species, with high abundance of biomass-burning tracers such as levoglucosan. Differences in PM2.5 EFs and chemical profiles were observed in relation to the type of incense burned. Nine indoor SVOCs considered to originate from sources other than incense combustion were enhanced during incense events. Time-resolved concentrations of these SVOCs correlated well with PM2.5 mass (R
2 > 0.75), suggesting that low-volatility SVOCs such as bis(2-ethylhexyl)phthalate and butyl benzyl phthalate partitioned to incense-generated PM2.5. Both direct emissions and enhanced partitioning of low-volatility indoor SVOCs to incense-generated PM2.5 can influence inhalation exposures during and after indoor incense use
Rhinocladiella similis: A Model Eukaryotic Organism for Astrobiological Studies on Microbial Interactions with Martian Soil Analogs.
Get PDFThe exploration of our solar system for microbial extraterrestrial life is the primary goal of several space agencies. Mars has attracted substantial attention owing to its Earth-like geological history and potential niches for microbial life. This study evaluated the suitability of the polyextremophilic fungal strain Rhinocladiella similis LaBioMMi 1217 as a model eukaryote for astrobiology. Comprehensive genomic analysis, including taxonomic and functional characterization, revealed several R. similis genes conferring resistance to Martian-like stressors, such as osmotic pressure and ultraviolet radiation. When cultured in a synthetic Martian regolith (MGS-1), R. similis exhibited altered morphology and produced unique metabolites, including oxylipins, indolic acid derivatives, and siderophores, which might be potential biosignatures. Notably, oxylipins were detected using laser desorption ionization mass spectrometry, a technique slated for its use in the upcoming European Space Agency ExoMars mission. Our findings enhance the understanding of extremophilic fungal metabolism under Martian-like conditions, supporting the potential of black yeasts as viable eukaryotic models in astrobiological studies. Further research is necessary to validate these biosignatures and explore the broader applicability of R. similis in other extraterrestrial environments
Social dominance influences individual susceptibility to an evolutionary trap in mosquitofish.
Get PDFPlastic pollution threatens almost every ecosystem in the world. Critically, many animals consume plastic, in part because plastic particles often look or smell like food. Plastic ingestion is thus an evolutionary trap, a phenomenon that occurs when cues are decoupled from their previously associated high fitness outcomes. Theory predicts that dominance hierarchies could dictate individual responses to evolutionary traps across social environments, but the social dimension of evolutionary trap responses has rarely been investigated. We tested how variation in group size influences the formation of dominance relationships and, in turn, how these dominance relationships drive differences in foraging behavior in Western mosquitofish (Gambusia affinis). This included foraging for a variety of familiar and novel food-like items, including microplastics. Overall, dominant individuals were often the first to sample food and had higher bite rates than subordinates, including when foraging for microplastics. Importantly, how dominance affected foraging behavior depended on group size and on whether groups were presented with familiar or novel foods. Furthermore, individuals were consistent in their foraging behavior across trials with different group sizes, indicating the formation of stable social roles. These results suggest that predicting the ecological and evolutionary consequences of evolutionary traps will require an understanding of how social structures influence trap susceptibility
Foreword: ʻAmui ʻi Muʻa/Ancient Futures—Back to the Future
Get PDFA short introduction to the ʻAmui ʻi Muʻa/Ancient Futures project, presented in both English and Tongan, by the Honorable Lord Vaea, ‘Alipate Tuʻivanuavou Vaea of Houma
What are the Public Health and Environmental Implications of Drayage Truck Electrification Targets in California?
Get PDFTo better understand the implications of transitioning drayage trucks to zero-emission, we analyzed the health impacts and GHG freeway emissions from diesel-powered drayage trucks and the benefits of replacing them with zero-emission trucks, accounting for current and expected air quality regulations. Our study area stretched between the San Pedro Bay and the Inland Empire, home to large warehouse complexes. We focused on two years: 2012 (when pre-2007 drayage trucks were phased out in the Clean Air Action Plan), and 2035 (the deadline in Executive Order N-79-20). Our analyses incorporated projections of the size and composition of the vehicle fleets from data collected by the California Air Resources Board (CARB), estimates of future emission factors from the U.S. Environmental Protection Agency that account for projected technology improvements, and projected increases in cargo demand at the ports in 2035 compared to 2012
CryoEM structure and small-angle X-ray scattering analyses of porcine retinol-binding protein 3.
Get PDFThe vertebrate visual cycle hinges on enzymatically converting all-trans-retinol (at-ROL) into 11-cis-retinal (11c-RAL), the chromophore that binds to opsins in photoreceptors, forming light-responsive pigments. When struck by a photon, these pigments activate the phototransduction pathway and initiate the process of vision. The enzymatic isomerization of at-ROL, crucial for restoring the visual pigments and preparing them to receive new light stimuli, relies on various enzymes found in both the photoreceptors and retinal pigment epithelium cells. To function effectively, retinoids must shuttle between these two cell types. Retinol-binding protein 3 (RBP3), located in the interphotoreceptor matrix, probably plays a pivotal role in this transport mechanism. Comprised of four retinoid-binding modules, RBP3 also binds fatty acids, potentially aiding retinal function by facilitating the loading and unloading of different retinoids at specific cell types thereby directing the cycle. In this study, we present a 3.67 Å cryoEM structure of porcine RBP3, along with molecular docking analysis and corroborative in-solution small-angle X-ray scattering data for titration of RBP3 with relevant ligands, that also give insights on RBP3 conformational adaptability
Superconducting quasiparticle-amplifying transmon: A qubit-based sensor for meV-scale phonons and single terahertz photons
Get PDFWith great interest from the quantum computing community, an immense amount of R&D effort has been invested into improving superconducting qubits. The technologies developed for the design and fabrication of these qubits can be directly applied to applications for ultralow-threshold particle detectors, e.g., low-mass dark matter and far-infrared photon sensing. We propose a novel energy-resolving sensor based on the transmon qubit architecture combined with a signal-enhancing superconducting quasiparticle amplification stage. We refer to these sensors as SQUATs: superconducting quasiparticle-amplifying transmons. We detail the operating principle and design of this new sensor and predict that, with minimal R&D effort, solid-state-based detectors patterned with these sensors can achieve sensitivity to single terahertz photons, and sensitivity to phonons in the detector absorber substrate on the microsecond timescale. Published by the American Physical Society 202
Single-Institution Experience With Nononcologic Total Femoral Replacement.
Get PDFBACKGROUND: Revision hip and knee arthroplasty volume continues to rise, and total femur replacement (TFR) remains a key salvage option in patients with extensive bone loss. Prior research has demonstrated mixed results of this procedure, and this study aimed to characterize the outcomes of nononcologic TFR in one of the largest single-center modern series. METHODS: A retrospective analysis was conducted on 23 nononcologic TFR procedures performed on 22 patients between 2012 and 2021. Primary outcomes included TFR revision rate and indication for revision, while secondary outcomes included overall reoperation rate, complications, patient ambulatory status, and assistive device requirements. RESULTS: The average age at time of TFR was 65.7 years, with periprosthetic fracture (65.2%) and periprosthetic joint infection (34.8%) as predominant indications. More than half of patients (52.2%) required TFR revision, primarily due to periprosthetic joint infection (75.0%). Despite a high complication profile, only 1 patient underwent limb amputation and there was only 1 mortality during the study period. Overall, 63.6% of patients were ambulating (assisted or unassisted) at final follow-up. CONCLUSIONS: Nononcologic TFR remains a viable limb-salvage option for patients undergoing revision arthroplasty with extensive bone loss. Despite a notable revision rate and infection risk, the majority of patients maintain or regain ambulatory function, emphasizing the procedures role in preserving limb function. Clinicians should weigh potential complications when considering TFR, emphasizing patient counseling and risk mitigation strategies
Changes in daily stress reactivity and changes in physical health across 18 years of adulthood.
Get PDFBACKGROUND: Stress plays a pivotal role in physical health. Although many studies have linked stress reactivity (daily within-person associations between stress exposure and negative affect) to physical health outcomes, we know surprisingly little about how changes in stress reactivity are related to changes in physical health. PURPOSE: The current study examines how change in stress reactivity over 18 years is related to changes in functional health and chronic health conditions. METHODS: Three measurement bursts from the National Study of Daily Experiences (N = 2880; 55% female) each included daily measures of stressor exposure and negative affect across 8 consecutive days, yielding 33 944 days of data across 18 years of adulthood. At each wave, participants reported their functional health limitations (ie, basic activities of daily living [ADL] and instrumental activities of daily living [IADL]) and chronic health conditions. Multilevel structural equation models simultaneously modeled stress reactivity at Level 1, longitudinal changes in stress reactivity at Level 2, and the association between changes in stress reactivity and changes in functional limitations and chronic conditions at Level 3. RESULTS: Higher levels of stress reactivity at baseline were associated with more functional health limitations 18 years later (ADLs: Est. = 0.90, P = .001; IADLs: Est. = 1.78, P < .001). Furthermore, individuals who increased more in their stress reactivity across the 18-year period also showed greater increases in their functional health limitations (ADLs: Est. = 4.02, P = .017; IADLs: Est. = 5.74, P < .001) and chronic conditions (Est. = 11.17, P = .008). CONCLUSIONS: These findings highlight the strong connection between health and stress in daily life, and how they travel together across adulthood
