Leaf Phenology and Freeze Tolerance of the Invasive Tree Pyrus calleryana (Rosaceae) and Potential Native Competitors

Pyrus calleryana is quickly becoming one of the most problematic invasive species in the Eastern and Central part of the United States. Pyrus calleryana is an early successional species that quickly proliferates in highly disturbed soils such as old fields and younger prairies. Currently, this species poses a large threat to land managers as it changes the successional trajectories of forest and prairie systems, creating new novel ecosystems. Pyrus calleryana outcompetes most native early successional species and is relatively understudied. The mechanism in which Pyrus calleryana utilizes to dominate ecosystems are not fully understood, but one theory is Pyrus calleryana extended leaf phenology in comparison to other native woody successional species. We hypothesized that Pyrus calleryana has a longer leaf phenology than two native woody species, Populus deltoides and Plantanus occidentalis. We observed these three species at 3 sites in Dayton, OH from December 2019 to November of 2020. A frost event in May also gave us the opportunity to understand frost tolerance with these species. We found that Pyrus calleryana began leafing out almost a month before its native competitors in the spring and kept its leaves on significantly longer than both P.deltoides and P.occidentalis (p\u3c0.001) throughout the fall. During the frost event, almost every single leaf on P.occidentalis died and almost 70% of the leaves on P.deltoides were damaged. However, Pyrus calleryana only had damage on 6% of its leaves. Our experiment suggests that Pyrus calleryana uses an extended leaf phenology as a mechanism to outcompete native successional species as it is able to photosynthesize longer, which builds up carbon and nutrient reserves, and is able to withstand frost events

Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana (Roseaceae) and potential native competitors

Pyrus calleryana is one of the most problematic invasive species in the eastern United States. The mechanisms that enable Py. calleryana to establish and outcompete native plants are not fully understood but likely include a profile of advantageous traits. Extended leaf phenology is a characteristic noted in many woody invasive plants. Leaf phenology of Py. calleryana and two native woody species, Populus deltoides and Platanus occidentalis, was observed in natural areas near Dayton, OH from December 2019 to November 2020. A frost event in May also gave us the serendipitous opportunity to assess frost tolerance of these species. We found that Py. calleryana began leafing out almost a month before its native competitors in the spring and kept its leaves on significantly longer than both Po. deltoides and Pl. occidentalis throughout the fall. After the frost event, almost every leaf on Pl. occidentalis died and almost 70% of the leaves on Po. deltoides were damaged; however, Py. calleryana exhibited damage on only 6% of its leaves. Our study suggests that Py. calleryana has a nearly 1-mo advantage in leaf phenology in both spring and fall, and much greater frost tolerance, as compared with native species. These attributes likely contribute to its capacity to outcompete native trees in early successional habitats

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Abstract social categories facilitate access to socially skewed words.

Recent work has shown that listeners process words faster if said by a member of the group that typically uses the word. This paper further explores how the social distributions of words affect lexical access by exploring whether access is facilitated by invoking more abstract social categories. We conduct four experiments, all of which combine an Implicit Association Task with a Lexical Decision Task. Participants sorted real and nonsense words while at the same time sorting older and younger faces (exp. 1), male and female faces (exp. 2), stereotypically male and female objects (exp. 3), and framed and unframed objects, which were always stereotypically male or female (exp. 4). Across the experiments, lexical decision to socially skewed words is facilitated when the socially congruent category is sorted with the same hand. This suggests that the lexicon contains social detail from which individuals make social abstractions that can influence lexical access

Leaf Phenology of Callery Pear: Frost Damage

This dataset is one of three affiliated with the paper Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana Roseaceae) and potential native competitors. The other two datasets are: Leaf Phenology of Callery Pear: Spring Leaf Phenology of Callery Pear: Fallhttps://ecommons.udayton.edu/mcewanlab_3_data/1008/thumbnail.jp

Leaf Phenology of Callery Pear: Fall

This dataset is one of three affiliated with the paper Leaf phenology and freeze tolerance of the invasive tree Pyrus calleryana Roseaceae) and potential native competitors. The other two datasets are: Leaf Phenology of Callery Pear: Spring Leaf Phenology of Callery Pear: Frost Damagehttps://ecommons.udayton.edu/mcewanlab_3_data/1007/thumbnail.jp

Leaf Phenology of Callery Pear: Spring

https://ecommons.udayton.edu/mcewanlab_3_data/1006/thumbnail.jp