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Recent Submissions

Tourisms’ Tristes Tropiques II: Cultural Landscapes
(eTropic: electronic journal of studies in the Tropics, 2026-04-11) Guerrón Montero, Carla; Lundberg, Anita
In this second special issue on “Tourisms’ Tristes Tropiques” we explore “Cultural Landscapes” socio-culturally and ecologically to show how they are intertwined with historical, colonial, and neocolonial aspects of tourism. The anthropology of tourism and critical tourism studies recognize tourism as both an industry and a cultural phenomenon, and this dual approach provides a lens for exploring how cultural landscapes are created, transformed, activated, and morphed by tourism. In this Introduction, we discuss how such studies have contributed to a nuanced and careful understanding of tourism's effects on cultural landscapes. The title of this special issue pays homage to Lévi-Strauss’s Tristes Tropiques, a memoir that, in many ways, anticipated the subfields explored here. Although Tristes Tropiques remains a controversial text, on its publication in 1955, it presented an intrepid indictment of racism and colonialism, and of travellers whose very act of mobility contributes to both. In this second issue, we venture across a range of tropical landscapes, from South America and Northern Australia to the Seychelles and the Andaman Islands, through India, Southeast Asia, and finally to tropical Africa. The contributors examine how tourism shapes and is shaped by cultures, ecologies, heritage, and history. Their analyses reveal cultural landscapes that are not merely scenic backdrops but rich spaces that local people engage with to counter the touristic forces of commodification and inequality. This second part of the double special issue on “Tourisms’ Tristes Tropiques” complements the analysis established in the first issue on the subtheme of “Literary Travels,” and furthers that analytical journey.
Snapshot of Diabetes Risk, Risk Awareness, and Lifestyle Change Factors in Older Adults Attending Delaware Senior Centers
(Delaware Journal of Public Health, 2026-04-15) Ruggiero, Laurie; Orsega-Smith, Elizabeth
Diabetes prevalence increases with age. Senior centers offer an opportunity to reach community dwelling older adults to educate them about diabetes and its prevention. Objective. The objective of the study was to examine diabetes/pre-diabetes occurrence, risk factors, and awareness, and lifestyle behaviors; and compare lifestyle behaviors in three diabetes risk-related subgroups (diabetes, lower risk; higher risk) in older adults attending senior centers. Methods. A single occasion cross-sectional self-report survey was conducted at two Delaware senior centers. A total of 159 individuals participated in the survey. Results. Demographic characteristics were: 76.08 years old on average (SD = 7.89); 77.4% female; 1.9% Hispanic/Latino/Latinx; 84.2 White, and 13.3% Black/African American. Of this sample, 20.0% self-reported a diabetes diagnosis, 66.3% without known diabetes may have increased risk, and 29.8% were aware of their diabetes risk. Furthermore, more than half reported a lack of knowledge about pre-diabetes. For lifestyle behaviors, 73% reported being in the action/maintenance stages of change for physical activity, 53%-72% across areas of healthy eating, and 93% were nonsmokers. No significant differences were found between risk groups for these lifestyle areas. Conclusions/Policy Implications. These findings suggest potential gaps in older adults’ awareness of diabetes risk and opportunities for promoting healthy lifestyle behaviors. Senior centers offer a convenient opportunity to reach older adults, to offer tailored approaches to address gaps in their awareness of pre-diabetes and diabetes risk, and to link individuals with current senior center, state, and other programs to further support diabetes prevention in older adults.
Tandem bulk oxygen diffusion and surface reactions in reducible metal oxides control redox cycle dynamics
(Nature Communications, 2026-04-11) Quentin Kim; George, Yan; Worrad, Alfred; Srinivas, Sanjana; Yoon, Sinmyung; Sourav, Sagar; Boscoboinik, J. Anibal; Zheng, Weiqing; Vlachos, Dionisios G.
The interplay between bulk oxygen diffusion and surface reactions in reducible metal oxides is key in heterogeneous catalysts, but direct measurements of oxygen mobility, transient kinetics, and in situ spectroscopies have been lacking. Here, we reveal complex dynamic behavior of ceria-zirconia by H2 using transient kinetics via mass spectrometry and in situ Raman and near-ambient pressure x-ray photoelectron spectroscopies. Molecular dynamics simulations with a machine learning potential delineate competitive oxygen diffusion mechanisms, with an optimal mobility at intermediate reductions. We expose a compensation between vacancy availability and lattice distortion at intermediate to high reductions and Frenkel defects at low reductions, underscoring a potential deficiency of 16O/18O exchange experiments in deducing oxygen mobility. Vacancies in proximity require electron localization on Ce atoms further away. The continuous replenishment of surface oxygen results in a varying reduction rate, with H2 dissociation being the rate-limiting step. Multiscale transient simulations, consistent with experiments, indicate catalysts of potentially spatially varying oxidation states. The approach is broadly applicable to reducible oxide materials.
Diffusion-Controlled Solute and Isotope Transport in the Milk River Aquifer System, Alberta, Canada: Implications for Dating Old Groundwater
(ACS Earth and Space Chemistry, 2026-04-09) Musy, Stephanie L.; Purtschert, Roland; Sturchio, Neil C.; Heraty, Linnea J.; Mueller, Peter; Lantis, Jeremy; Bishof, Michael N.; Vockenhuber, Christof; Date, Avadhoot; Mayer, Bernhard; Yokochi, Reika
Krypton-81 (81Kr) and chlorine-36 (36Cl) are among the few isotopic tracers capable of constraining groundwater residence times on 105–106 year timescales. In sedimentary aquifer systems bounded by low-permeability units, however, diffusive solute exchange can strongly modify tracer distributions and bias apparent ages derived from concentration ratios. In the transboundary Milk River Aquifer (MRA), progressive chloride enrichment caused by diffusion across shale aquitards complicates the interpretation of 36Cl/Cl as a chronometer. Here, we combine new measurements of 81Kr, 36Cl, stable chlorine isotopes (37Cl/35Cl), and 14C with advection–diffusion transport modeling to quantify the importance of matrix diffusion on tracer systematics and inferred groundwater ages. The simulations reproduce the observed decrease in 36Cl/Cl and concomitant increase in δ37Cl along regional flow paths, demonstrating that diffusive influx of Cl-rich aquitard water dominates the evolution of the chlorine isotope system. In contrast, modeled and observed 81Kr activities show substantially lower sensitivity to diffusive exchange over the timescales considered. A comparison of simulated and measured tracer relationships indicates that, in the MRA, apparent ages derived from 36Cl primarily reflect chloride addition rather than radioactive decay, whereas 81Kr provides a more robust and conservative chronometer for fossil groundwater. These results highlight the value of integrating stable and radioactive chlorine isotopes with noble gas dating and explicit transport modeling to disentangle decay from transport effects. The approach developed here provides a quantitative framework for interpreting multitracer data sets in regional aquifers affected by long-term diffusive exchange and has broader implications for assessing fossil groundwater resources in similar hydrogeological settings.
White matter microstructure of sensorimotor projection fibers in chronic low back pain
(PAIN Reports, 0026-04-07) Gilliam, John R; Vendemia, Jennifer M.C; Baty, Zachary; Silfies, Sheri P.; Coombes, Stephen A.
Introduction: Chronic low back pain (cLBP) is linked to altered cortical sensorimotor structure and function, yet white matter microstructure in sensorimotor projection fibers remains poorly characterized. Objective: To address this gap, we used diffusion MRI to comprehensively characterize sensorimotor projection fibers in 44 patients with cLBP and 41 matched healthy controls. Methods: We estimated an array of microstructural measures, including fractional anisotropy (FA), extracellular free water fraction (FW), free water–corrected FA (fwcFA), and neurite orientation dispersion and density imaging (NODDI) metrics. Results: General linear models identified significantly higher FA and fwcFA and lower orientation dispersion index (ODI) in cLBP vs HC within projection fibers emanating from the primary somatosensory and motor cortices (all corrected P-values <0.05). Conjunction analyses indicated spatial overlap between increased anisotropy and reduced ODI, suggesting a reduction in geometric complexity of neurites underlies this group difference. Partial correlations revealed significant relationships between diffusion metrics and anxiety and depressive symptoms (FA: r = −0.41, P < 0.01; fwcFA: r = −0.38, P = 0.01; ODI: r = 0.38, P = 0.01). The relationships between anxiety and depressive symptoms and diffusion MRI metrics are consistent with work outside of chronic pain. Conclusion: Our results align differences in white matter microstructure with previous neurophysiological evidence that identifies the primary sensorimotor cortices as relevant in cLBP and emphasizes the interrelatedness of anxiety and depressive symptoms and sensorimotor structure.