2 research outputs found
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Dormancy-defense syndromes and tradeoffs between physical and chemical defenses in seeds of pioneer species
Seeds of tropical pioneer trees have chemical and physical characteristics that determine their capacity to persist in the soil seed bank. These traits allow seeds to survive in the soil despite diverse predators and pathogens, and to germinate and recruit even decades after dispersal. Defenses in seedlings and adult plants often are described in terms of tradeoffs between chemical and physical defense, but the interplay of defensive strategies has been evaluated only rarely for seeds. Here we evaluated whether classes of seed defenses were negatively correlated across species (consistent with tradeoffs in defense strategies), or whether groups of traits formed associations across species (consistent with seed defense syndromes). Using 16 of the most common pioneer tree species in a neotropical lowland forest in Panama we investigated relationships among four physical traits (seed fracture resistance, seed coat thickness, seed permeability, and seed mass) and two chemical traits (number of phenolic compounds and phenolic peak area), and their association with seed persistence. In addition, seed toxicity was assessed with bioassays in which we evaluated the activity of seed extracts against representative fungal pathogens and a model invertebrate. We did not find univariate tradeoffs between chemical and physical defenses. Instead, we found that seed permeability – a trait that distinguishes physical dormancy from other dormancy types – was positively associated with chemical defense traits and negatively associated with physical defense traits. Using a linear discriminant analysis and a hierarchical cluster analysis we found evidence to distinguish three distinct seed defense syndromes that correspond directly with seed dormancy classes (i.e., quiescent, physical, and physiological). Our data suggest that short and long‐term persistence of seeds can be achieved via two strategies: having permeable seeds that are well defended chemically, corresponding to the physiologically dormant defense syndrome; or having impermeable seeds that are well defended physically, corresponding to the physically dormant defense syndrome. In turn, transient seeds appear to have a lower degree of chemical and physical defenses, corresponding to the quiescent defense syndrome. Overall, we find that seed defense and seed dormancy are linked, suggesting that environmental pressures on seed persistence and for delayed germination can select for trait combinations defining distinct dormancy‐defense syndromes
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Anticoagulation Quality Assessment and Risk Evaluation in Patients with Nonvalvular Atrial Fibrillation (NVAF)
Class of 2023 AbstractSpecific Aims: To describe patients’ antithrombotic selection based on their CHA2DS2-VASc
score to identify treatment gaps in preventing strokes among patients with nonvalvular atrial
fibrillation.
Methods: Retrospective descriptive study of patients diagnosed with nonvalvular atrial
fibrillation at an outpatient cardiology clinic. De-identified data was extracted from Aprima
electronic health record and was collected for patients seen between January 1, 2020 and April
15, 2022. Types of data collected included demographics, height and weight, labs, medications of
interest, and conditions of interest. Only patients with a high CHA2DS2-VASc score category
were included in the final data analysis, which was conducted using Minitab.
Results: A total of 213 patients were included in the final analysis (mean age = 78; SD = 9; 79%
Caucasian; 53% male). Overall, 65% of patients were on oral anticoagulants, and about 72% of
patients had a CHA2DS2-VASc score ≥4. 36% of high-risk patients were not receiving oral
anticoagulant therapy. For patients with CHA2DS2-VASc score of 2 through 5, more than 10%
of patients were not on antithrombotic therapy and met the criteria for therapy. Among patients
on alternative direct oral anticoagulant dosing, approximately 60% were dosed lower than label
dosing. Conclusions: This study highlights treatment gaps among patients with nonvalvular atrial
fibrillation and describes those not on guideline-based antithrombic therapy and the use of
alternative dosing with direct oral anticoagulants.This item is part of the Pharmacy Student Research Projects collection, made available by the College of Pharmacy and the University Libraries at the University of Arizona. For more information about items in this collection, please contact Jennifer Martin, Librarian and Clinical Instructor, Pharmacy Practice and Science, [email protected]