2,666 research outputs found

    Climate change influences foliar nutrition and metabolism of red maple (Acer rubrum) trees in a northern hardwood forest

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    © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Blagden, M., Harrison, J. L., Minocha, R., Sanders-DeMott, R., Long, S., & Templer, P. H. Climate change influences foliar nutrition and metabolism of red maple (Acer rubrum) trees in a northern hardwood forest. Ecosphere, 13(2), (2022): e03859. https://doi.org/10.1002/ecs2.3859.Mean annual air temperatures are projected to increase, while the winter snowpack is expected to shrink in depth and duration for many mid- and high-latitude temperate forest ecosystems over the next several decades. Together, these changes will lead to warmer growing season soil temperatures and an increased frequency of soil freeze–thaw cycles (FTCs) in winter. We took advantage of the Climate Change Across Seasons Experiment (CCASE) at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire, USA, to determine how these changes in soil temperature affect foliar nitrogen (N) and carbon metabolism of red maple (Acer rubrum) trees in 2015 and 2017. Earlier work from this study revealed a similar increase in foliar N concentrations with growing season soil warming, with or without the occurrence of soil FTCs in winter. However, these changes in soil warming could differentially affect the availability of cellular nutrients, concentrations of primary and secondary metabolites, and the rates of photosynthesis that are all responsive to climate change. We found that foliar concentrations of phosphorus (P), potassium (K), N, spermine (a polyamine), amino acids (alanine, histidine, and phenylalanine), chlorophyll, carotenoids, sucrose, and rates of photosynthesis increased with growing season soil warming. Despite similar concentrations of foliar N with soil warming with and without soil FTCs in winter, winter soil FTCs affected other foliar metabolic responses. The combination of growing season soil warming and winter soil FTCs led to increased concentrations of two polyamines (putrescine and spermine) and amino acids (alanine, proline, aspartic acid, γ-aminobutyric acid, valine, leucine, and isoleucine). Treatment-specific metabolic changes indicated that while responses to growing season warming were more connected to their role as growth modulators, soil warming + FTC treatment-related effects revealed their dual role in growth and stress tolerance. Together, the results of this study demonstrate that growing season soil warming has multiple positive effects on foliar N and cellular metabolism in trees and that some of these foliar responses are further modified by the addition of stress from winter soil FTCs.This research was supported by an NSF Long Term Ecological Research (LTER) Grant to Hubbard Brook (NSF 1114804 and 1637685) and an NSF CAREER grant to PHT (NSF DEB1149929). RSD was supported by NSF DGE0947950, a Boston University (BU) Dean's Fellowship, and the BU Program in Biogeoscience. Jamie Harrison was supported by a BU Dean's Fellowship. Megan Blagden was supported by a BU Undergraduate Research Opportunity Program fellowship. This manuscript is a contribution to the Hubbard Brook Ecosystem Study. Hubbard Brook is part of the LTER network, which is supported by the NSF

    Endovascular treatment for ischemic stroke patients with and without atrial fibrillation, and the effects of adjunctive pharmacotherapy:a narrative review

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    Introduction: Endovascular thrombectomy (EVT) is associated with good clinical outcomes in patients with ischemic stroke, but the impact of EVT on clinical outcomes in patients with ischemic stroke with and without atrial fibrillation (AF), and the effect of adjunctive pharmacological therapies with EVT, remains unclear. Areas covered: The goal of this narrative review is to provide an overview of studies which have examined: 1) associations between EVT and outcomes for patients following ischemic stroke, 2) associations between EVT and outcomes for patients following ischemic stroke with and without AF, including function, reperfusion, hemorrhage, and mortality, 3) the effect of adjunctive pharmacological therapies peri- and post-thrombectomy, and 4) integration of prehospital care on endovascular treatment outcomes. Expert opinion: There is little evidence from randomized controlled trials on the effect of AF on stroke outcomes following EVT and the safety and efficacy of AF treatment in the peri-EVT such as tirofiban or Intravenous thrombolysis with Non-vitamin K Antagonist Oral Anticoagulant. The available evidence from observational studies on AF and EVT outcomes is inconsistent, but factors such as procedural EVT devices, the center volume, clinician experience, stroke recognition, and inclusion criteria of studies have all been associated with poorer clinical outcomes. Enhancing the clinical network among prehospital and hospitals will facilitate direct transfer to EVT centers, reducing stroke onset to EVT time and optimizing stroke outcomes.</p

    Risk of myocardial infarction and ischemic stroke in individuals with first-diagnosed paroxysmal vs. non-paroxysmal atrial fibrillation under anticoagulation

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    AimsThere is conflicting evidence on whether the type of atrial fibrillation (AF) is associated with risk of cardiovascular events, including acute myocardial infarction (MI) and ischemic stroke. The aim of the present study was to investigate whether the risk of MI and ischemic stroke differs between individuals with first-diagnosed paroxysmal vs. non-paroxysmal AF treated with anticoagulants.Methods and resultsDe-identified electronic medical records from the TriNetX federated research network were used. Individuals with a new diagnosis of paroxysmal AF who had no evidence of other types of AF in their records were 1:1 propensity score-matched with individuals with non-paroxysmal AF, defined as persistent or chronic AF, who had no evidence of other types of AF in their records. All patients were followed for three years for the outcomes of MI and ischemic stroke. Cox proportional hazard models were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). In the propensity-matched cohort, among 24 848 well-matched AF individuals [mean age 74.4 ± 10.4; 10 101 (40.6%) female], 410 (1.7%) were diagnosed with acute MI and 875 (3.5%) with ischemic stroke during the three-year follow-up. Individuals with paroxysmal AF had significantly higher risk of acute MI (HR: 1.65, 95%CI: 1.35-2.01) compared to those with non-paroxysmal AF. First diagnosed paroxysmal AF was associated with higher risk of non-ST elevation MI (nSTEMI) (HR: 1.89, 95%CI: 1.44-2.46). No significant association was observed between the type of AF and risk of ischemic stroke (HR: 1.09, 95%CI: 0.95-1.25).ConclusionPatients with first-diagnosed paroxysmal AF had higher risk of acute MI compared to individuals with non-paroxysmal AF, attributed to the higher risk of nSTEMI among patients with first-diagnosed paroxysmal AF. There was no significant association between type of AF and risk of ischemic stroke

    Combating the Business Manipulator Using Armor of God: Faith Integration Cycle for Ephesians 6:10-18

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    This paper is designed to provide a framework, the Faith Integration Cycle (FIC), for developing,implementing, assessing, and evaluating faith integration in business courses. The paper also demonstrates how faculty—working together—created a multi-disciplinary faith integration effort by providing the theological link between the Bible passage Ephesians 6:10-18 and business disciplines. To assist faculty with faith integration, specific examples of utilizing the FIC are demonstrated with class activities or assignments, including sample syllabus descriptions and grading rubrics. In addition, a general pre- and post-assessment has been provided to assist with the evaluation of the effectiveness of an activity/assignment to achieve faith integration in the classroom. Utilizing the FIC has the potential to be expanded to an entire business program-level faith integration project as suggested by Holder (2006)

    Associations between COVID-19 and 30-day thromboembolic events and mortality in people with dementia receiving antipsychotic medications

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    BACKGROUND: Antipsychotic medications are frequently prescribed to people with dementia to manage behavioural and psychological symptoms. Using a global federated research network, the objectives were to determine: 1) if COVID-19 is associated with 30-day thromboembolic events and mortality for people with dementia receiving antipsychotic medications; and 2) if the proportion of people with dementia receiving antipsychotics is higher during the COVID-19 pandemic compared to 2019. METHODS: A retrospective cohort study was conducted using TriNetX, a global federated health research network. The network was searched for people aged ≥ 65 years with dementia, COVID-19 and use of antipsychotics in the 30-days prior to COVID-19 recorded in electronic medical records between 20/01/2020 and 05/12/2020. These individuals were compared to historical controls from 2019 with dementia and use of antipsychotics in the 30-days before a visit to a participating healthcare organisation. Propensity score matching for age, sex, race, co-morbidities and use of antidepressants and anticonvulsants was used to balance cohorts with and without COVID-19. RESULTS: Within the TriNetX network, 8414 individuals with COVID-19, dementia and use of antipsychotics and 31,963 historical controls were identified. After propensity score matching there were 8396 individuals with COVID-19 and 8396 historical controls. The cohorts were well balanced for age, sex, race, co-morbidities and use of antidepressants and anticonvulsants. The odds of 30-day thromboembolic events and all-cause mortality were significantly higher in adults with COVID-19 (Odds Ratios: 1.36 (95% confidence interval (CI): 1.21–1.52) and 1.93 (1.71–2.17), respectively). The number of people with dementia with a visit to a participating healthcare organisation was lower between 20/01/2020 and 05/12/2020 (n = 165,447) compared to the same period in 2019 (n = 217,391), but the proportion receiving antipsychotics increased from 14.7% (95%CI: 14.6–14.9%) to 16.4% (95%CI: 16.2–16.5%), P < .0001. CONCLUSIONS: These findings add to the evidence base that during the COVID-19 pandemic there was an increase in the proportion of people with dementia receiving antipsychotics. The negative effects of antipsychotics in patients with dementia may be compounded by concomitant COVID-19
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