Publications by authors named "William Cornwell"

Cornwell, William, Aaron L Baggish, Christoph Dehnert, Benjamin D Levine, and Andrew M Luks. Clinical Conundrum: Climbing at the Extremes of High Elevation with Nonischemic Cardiomyopathy. 00:00-00, 2024.

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Deadwood represents globally important carbon (C), nitrogen (N), and phosphorus (P) pools. Current wood nutrient dynamics models are extensions of those developed for leaf litter decomposition. However, tissue structure and dominant decomposers differ between leaf and woody litter, and recent evidence suggests that decomposer stoichiometry, in combination with litter quality, may affect nutrient release.

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Exercise testing is frequently incorporated into management of patients with cardiovascular and/or pulmonary disease. A lifelong commitment to exercise promotes cardiac remodeling, leading to changes in structure and function of the atria and ventricles, commonly referred to as the "athletic heart." Stress testing is also incorporated into the management of athletes for a variety of reasons, such as identifying the cause of exertional symptoms, determining level of fitness and training zones, or assessing for acquired cardiomyopathies.

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  • The "2024 Guideline for the Primary Prevention of Stroke" updates the previous 2014 guidelines, providing new strategies for preventing strokes in individuals without a prior history.
  • A thorough review of relevant literature from various databases was conducted to inform these updated recommendations, ensuring they are based on the latest research.
  • The guidelines emphasize the preventability of strokes and include new sex-specific recommendations, aligning with the American Heart Association's Life's Essential 8, while also updating previous recommendations based on recent research findings.
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Identification of long-term calcium channel blocker (CCB) responders with acute vasodilator challenge is critical in the evaluation of patients with pulmonary arterial hypertension. Currently there is no standardized approach for use of supplemental oxygen during acute vasodilator challenge. In this retrospective analysis of patients identified as acute vasoresponders, treated with CCBs, all patients had hemodynamic measurements in three steps: (1) at baseline; (2) with 100% fractional inspired oxygen; and (3) with 100% fractional inspired oxygen plus inhaled nitric oxide (iNO).

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Acute hypoxia increases pulmonary arterial (PA) pressures, though its effect on right ventricular (RV) function is controversial. The objective of this study was to characterize exertional RV performance during acute hypoxia. Ten healthy participants (34 ± 10 years, 7 males) completed three visits: visits 1 and 2 included non-invasive normoxic (fraction of inspired oxygen ( ) = 0.

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Background: Detecting right heart failure post left ventricular assist device (LVAD) is challenging. Sensitive pressure-volume loop assessments of right ventricle (RV) contractility may improve our appreciation of post-LVAD RV dysfunction.

Methods: Thirteen LVAD patients and 20 reference (non-LVAD) subjects underwent comparison of echocardiographic, right heart cath hemodynamic, and pressure-volume loop-derived assessments of RV contractility using end-systolic elastance (Ees), RV afterload by effective arterial elastance (Ea), and RV-pulmonary arterial coupling (ratio of Ees/Ea).

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  • First-degree atrioventricular (AV) block is often found in athletes during ECG screenings, especially when the PR interval exceeds 200 ms.
  • Profound first-degree AV block (PR interval >400 ms) and Mobitz type I (Wenckebach) second-degree AV block are rarer and may need individual assessments, especially if there's concern about heart structure.
  • In one case, an asymptomatic athlete with profound first-degree AV block and Mobitz type I was cleared for sports after normal echocardiograms, highlighting the importance for physicians to recognize when further evaluation is necessary.
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  • Long COVID affects 25-30% of people who have had SARS-CoV-2, leading to symptoms like extreme fatigue, difficulty in performing daily activities, and rapid heart rate.
  • There is a need for specific treatment strategies to help manage these symptoms, particularly through tailored exercise programs that accommodate the unique challenges faced by Long COVID patients.
  • This review emphasizes that structured exercise can counteract the effects of deconditioning, which often results from prolonged inactivity, and may help reduce the symptom burden in those suffering from Long COVID.
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  • Patients with heart failure with reduced ejection fraction (HFrEF) show sustained limitations in their exercise capacity even after receiving a continuous-flow left ventricular assist device (CF-LVAD).
  • The study monitored ten patients' hemodynamics and functional capacity through a series of cardiopulmonary exercise tests before and after CF-LVAD implantation to assess changes with different pump speeds.
  • Results indicated no significant improvement in maximal oxygen uptake or cardiovascular measurements following implantation, suggesting the need for further research on enhancing exercise capacity in HFrEF patients post-device insertion.
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  • Understanding the impact of symbiotic relationships on the ecology and evolution of fungal spores has been overlooked in research, even though these interactions are common in various ecosystems.
  • A comprehensive database of spore morphology, encompassing over 26,000 species, revealed significant variations in spore size linked to changes in symbiotic relationships.
  • This study shows that symbiotic status plays a more crucial role than climate in determining spore size distribution among plant-associated fungi, affecting their dispersal abilities compared to free-living fungi.
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Cardiac rehabilitation has strong evidence of benefit across many cardiovascular conditions but is underused. Even for those patients who participate in cardiac rehabilitation, there is the potential to better support them in improving behaviors known to promote optimal cardiovascular health and in sustaining those behaviors over time. Digital technology has the potential to address many of the challenges of traditional center-based cardiac rehabilitation and to augment care delivery.

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  • * During exercise, the right ventricle faces increased afterload that requires heightened contractility to maintain cardiac output, and failure to do so can lead to reduced exercise ability and poorer prognoses.
  • * Exercise testing and various noninvasive and invasive techniques can help assess right ventricular function and pulmonary vascular response, which are crucial for diagnosing and managing PH, but more research is needed to clarify their role in treatment.
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Premise: Continental-scale leaf trait studies can help explain how plants survive in different environments, but large data sets are costly to assemble at this scale. Automating the measurement of digitized herbarium collections could rapidly expand the data available to such studies. We used machine learning to identify and measure leaves from existing, digitized herbarium specimens.

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Irruption of herbivore populations due to the extirpation of predators has led to dramatic changes in ecosystem functioning worldwide. Herbivores compete with other species for their primary source of nutrition, plant biomass. Such competition is typically considered to occur between species in closely related clades and functional groups but could also occur with detritivores that consume senescent plant biomass.

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The photographic record is increasingly becoming an important biodiversity resource for primary research and conservation monitoring. However, globally, there are important gaps in this record even in relatively well-researched floras. To quantify the gaps in the Australian native vascular plant photographic record, we systematically surveyed 33 sources of well-curated species photographs, assembling a list of species with accessible and verifiable photographs, as well as the species for which this search failed.

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  • Exertional dyspnea is a key symptom of heart failure with reduced ejection fraction (HFrEF), but detailed data on how exertion affects heart and lung function is limited.
  • This study involved 35 HFrEF patients, analyzing their cardiovascular and pulmonary responses during exercise to determine how exertion impacts their hemodynamics.
  • The results showed significant increases in pressures in both the right atrium and pulmonary artery during exercise, indicating serious cardiopulmonary dysfunction that affects exercise capacity in patients with HFrEF.
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  • The 'Global Spectrum of Plant Form and Function Dataset' includes mean values for six key vascular plant traits, essential for understanding plant variation.
  • This dataset aggregates around 1 million trait records from the TRY database and other sources, encompassing 92,159 species mean values across 46,047 species.
  • Comprehensive data quality management and validation ensure this is the largest and most reliable collection of empirical data on vascular plant traits available.
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  • A 37-year-old athlete underwent a 90 km bicycle test to analyze the pressure and volume in the right ventricle.
  • The test showed that increased pressure in the right ventricle led to decreased efficiency in how the heart and arteries worked together, as well as a drop in cardiac output.
  • To keep up oxygen delivery, the body had to increase the difference between oxygen in the arteries and veins, highlighting how right ventricle performance impacts exercise capacity.
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As the number of observations submitted to the citizen science platform iNaturalist continues to grow, it is increasingly important that these observations can be identified to the finest taxonomic level, maximizing their value for biodiversity research. Here, we explore the benefits of acting as an identifier on iNaturalist.

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Mechanisms causing the post-acute sequelae of SARS-CoV-2 (long COVID) remain elusive, but the clinical phenotype is consistent with cardiac deconditioning. We report a case series of patients with long COVID whose symptoms improved/resolved with exercise and present exercise training as a novel therapeutic strategy for management of long COVID syndrome. ().

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CD4 regulatory T cells (Tregs) respond to environmental cues to permit or suppress inflammation, and atherosclerosis weakens Treg suppression and promotes plasticity. However, the effects of smoking plus morphine (SM + M) on Treg plasticity remain unknown. To determine whether SM + M promotes Treg plasticity to T helper 17 (Th17) cells, we analyzed the RNA sequencing data from SM, M, and SM + M treated Tregs and performed knowledge-based and IPA analysis.

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