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Proliferation of \u3cem\u3eChondrodonta\u3c/em\u3e as a Proxy of Environmental Instability at the Onset of OAE1a: Insights from Shallow-Water Limestones of the Apulia Carbonate Platform
Get PDFChondrodonta is an opportunistic, oyster-like bivalve, common in shallow-water carbonates of the Cretaceous Tethyan Realm. Despite its high abundance and widespread geographic distribution, the precise relationship between the early Aptian proliferation and environmental perturbations resulting from the Oceanic Anoxic Event 1a (OAE1a), has not been investigated. Stratigraphic and geochemical analyses of the lower Aptian Chondrodonta bedsets within the inner platform limestones of the Apulia Carbonate Platform (Gargano Promontory, southern Italy) are conducted to assess the environmental controls on the Chondrodonta proliferation and its timing and causal relationship to OAE1a. Chondrodonta occurs with sparse to common individuals within requieniid rudist floatstone–rudstones, forms monospecific biostromes during the early phase of stressed environmental conditions and then rapidly disappears at the peak of OAE1a. It proliferates in dysoxic seawater with relatively increased trophic sources, which correlate to increasing nutrient levels in the nearby pelagic realm. Chondrodonta-rich beds are associated worldwide with the onset of OAE1a and occur in a transitional context between a stable and a strongly stressed environment, where the opportunistic behaviour of Chondrodonta is rather efficient. Increasing nutrient load and unstable environmental conditions right below the peak of OAE1a created an environmental ‘window’ favourable for Chondrodonta to proliferate, outplaying the less tolerant benthos (for example, rudists). The occurrence, duration and position of the environmental window were controlled by local palaeogeographic and hydrodynamic settings (i.e. low energy, decreased seawater oxygenation and circulation). Further increase in inhospitable conditions, leading to OAE1a, constituted an upper threshold for Chondrodonta and allowed mesotrophic taxa like Bacinella–Lithocodium and orbitolinids to dominate the benthic communities. The present study suggests that the proliferation of Chondrodonta in shallow-water platform carbonates can be used as proxy for the initial phase of ecological stress related to OAE1a
Linking Ecomechanical Models and Functional Traits to Understand Phenotypic Diversity
Get PDFPhysical principles and laws determine the set of possible organismal phenotypes. Constraints arising from development, the environment, and evolutionary history then yield workable, integrated phenotypes. We propose a theoretical and practical framework that considers the role of changing environments. This \u27ecomechanical approach\u27 integrates functional organismal traits with the ecological variables. This approach informs our ability to predict species shifts in survival and distribution and provides critical insights into phenotypic diversity. We outline how to use the ecomechanical paradigm using drag-induced bending in trees as an example. Our approach can be incorporated into existing research and help build interdisciplinary bridges. Finally, we identify key factors needed for mass data collection, analysis, and the dissemination of models relevant to this framework
Influencer Marketing Between Mothers: The Impact of Disclosure and Visual Brand Promotion
No full textMothers are among the original social media influencers and their social media content plays a vital role in supporting and sustaining motherhood through relationships of social exchange while simultaneously supporting brand marketing efforts. This study, then, uses a within-subjects, repeated-measure experimental design to examine how increasing the overtness in the promotional explicitness through the text and images of mother influencers’ (Insta-Moms) Instagram posts disrupts mother consumers’ affective responses toward the messages either directly or indirectly, through perceptions of manipulative intent. Findings indicate adverse response when promotional disclosure was present but brand promotion was less overtly explicit, but when brands were both textually and visually promoted, it assuaged feelings of manipulative intent and enhanced affective response to the posts
Months-Long Spike in Aqueous Arsenic Following Domestic Well Installation and Disinfection: Short- and Long-Term Drinking Water Quality Implications
Get PDFExposure to high concentration geogenic arsenic via groundwater is a worldwide health concern. Well installation introduces oxic drilling fluids and hypochlorite (a strong oxidant) for disinfection, thus inducing geochemical disequilibrium. Well installation causes changes in geochemistry lasting 12 + months, as illustrated in a recent study of 250 new domestic wells in Minnesota, north-central United States. One study well had extremely high initial arsenic (1550 µg/L) that substantially decreased after 15 months (5.2 µg/L). The drilling and development of the study well were typical and ordinary; nothing observable indicated the very high initial arsenic concentration. We hypothesized that oxidation of arsenic-containing sulfides (which lowers pH) combined with low pH dissolution of arsenic-bearing Fe (oxyhydr)oxides caused the very high arsenic concentration. Geochemical equilibrium considerations and modeling supported our hypothesis. Groundwater equilibrium redox conditions are poised at the Fe(III)(s)/Fe(II)(aq) stability boundary, indicating arsenic-bearing Fe (oxyhydr)oxide mineral sensitivity to pH and redox changes. Changing groundwater geochemistry can have negative implications for home water treatment (e.g., reduced arsenic removal efficiency, iron fouling), which can lead to ongoing but unrecognized hazard of arsenic exposure from domestic well water. Our results may inform arsenic mobilization processes and geochemical sensitivity in similarly complex aquifers in Southeast Asia and elsewhere
Hope, Form, and Future in the Work of James Joyce
No full textHope and future are not the terms with which James Joyce has usually been read, but this book paints a picture of Joyce\u27s fiction in which hope and future assume the primary colo(u)rs.
Rando explores how Joyce\u27s texts, as early as Dubliners and A Portrait of the Artist as a Young Man, delineate a complex hope that is oriented toward the future with restlessness, dissatisfaction, and invention. He examines how Joyce envisions alternatives to the prevailing conventions of hope throughout his works and, in Ulysses and Finnegans Wake, develops formal techniques of spatializing hope to contemplate it from all sides.
Casting fresh light on the ways in which hope animates key aspects of Joyce\u27s approach to literary content and form, Rando moves beyond the limitations of negative critique and literary historicism to present a Joyce who thinks agilely about the future, politics, and possibility.https://digitalcommons.trinity.edu/mono/1175/thumbnail.jp
Accessible, Sustainable Outreach: New Priorities for an Online Orientation Program
Get PDFWhen paradigm-shifting events like the COVID-19 pandemic disrupt planning, as usual, libraries must rethink how they conduct traditional marketing and outreach activities like new student orientations. At Trinity University’s Coates Library, the traditional in-person orientation shifted to an asynchronous, online format. This article will detail how this change led to the development of new and reusable digital content for sustainable teaching and outreach, prioritized accessibility, and offered an alternative means of program assessment. Further, these changes provided an opportunity to reexamine some of the library’s previous goals and methods for first-year student outreach
[Review of the Book \u3cem\u3eChristianity, Empire, and the Spirit: (Re)Configuring Faith and Culture\u3c/em\u3e, by N. Medina]
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Triassic Foraminifera From the Great Bank of Guizhou, Nanpanjiang Basin, South China: Taxonomic Account, Biostratigraphy, and Implications for Recovery From End-Permian Mass Extinction
No full textForaminifera are important components of tropical marine benthic ecosystems and their recovery pattern from the end-Permian mass extinction can yield insights into the Mesozoic history of this group. Here we report the calcareous and agglutinated foraminifera recovered from five measured stratigraphic sections on the Great Bank of Guizhou, an uppermost Permian to Upper Triassic isolated carbonate platform in the Nanpanjiang Basin, south China. The material contains \u3e100 Triassic species, including three that are newly described (Arenovidalina weii n. sp., Meandrospira? enosi n. sp., and Spinoendotebanella lehrmanni n. gen., n. sp.), ranging from Griesbachian (Induan) to Cordevolian (Carnian) age. The species belong to the classes Miliolata, Textulariata, Fusulinata, Nodosariata, and to an unknown class housing all aragonitic forms of the orders Involutinida and Robertinida. Based on previously established conodont zones and carbon isotope chemostratigraphy, the Griesbachian (early Induan) through Illyrian (late Anisian) interval has been subdivided into 12 foraminiferal zones and two unnamed intervals devoid of foraminifera. Following the extinction at the Permian-Triassic boundary, habitable ecological niches of Griesbachian age were invaded by disaster taxa that subsequently became extinct during the Dienerian (late Induan) and left no younger descendants. The disaster taxa were replaced by Lazarus taxa with Permian origins, which were then decimated by the Smithian-Spathian (mid-Olenekian) boundary crisis. The tempo of recovery appears to have been modulated by environmental changes during the Griesbachian through Smithian that involved both climate change and expansion of anoxic ocean bottom waters. Uninterrupted and lasting recovery of benthic foraminifera did not begin until the Spathian