Convergence or redundancy: alternative views about the evolutionary genomics of character displacement.

An evolutionary debate contrasts the importance of genetic convergence versus genetic redundancy. In genetic convergence, the same adaptive trait evolves because of similar genetic changes. In genetic redundancy, the adaptive trait evolves using different genetic combinations, and populations might not share the same genetic changes. Here we address this debate by examining single nucleotide polymorphisms (SNPs) associated with the rapid evolution of character displacement in Anolis carolinensis populations inhabiting replicate islands with and without a competitor species (1Spp and 2Spp islands, respectively). We identify 215-outliers SNPs that have improbably large FST values, low nucleotide variation, greater linkage than expected and that are enriched for genes underlying animal movement. The pattern of SNP divergence between 1Spp and 2Spp populations supports both genetic convergence and genetic redundancy for character displacement. In support of genetic convergence: all 215-outliers SNPs are shared among at least three of the five 2Spp island populations, and 23% of outlier SNPS are shared among all five 2Spp island populations. In contrast, in support of genetic redundancy: many outlier SNPs only have meaningful allele frequency differences between 1Spp and 2Spp islands on a few 2Spp islands. That is, on at least one of the 2Spp islands, 77% of outlier SNPs have allele frequencies more similar to those on 1Spp islands than to those on 2Spp islands. Focusing on genetic convergence is scientifically rigorous because it relies on replication. Yet, this focus distracts from the possibility that there are multiple, redundant genetic solutions that enhance the rate and stability of adaptive change.

Singapore radiographers' perceptions and expectations of artificial intelligence - A qualitative study.

INTRODUCTION: With the emergence of artificial intelligence (AI) in medical imaging, radiographers are likely to be at the forefront of this technological advancement. Studies have therefore been conducted recently to understand radiographers' opinions on AI adoption. This study extends that work by using a qualitative approach to further explore radiographers' knowledge, perceptions, and expectations of AI. METHOD: Six online focus groups were conducted with 22 radiographers from the three public healthcare clusters in Singapore. They were purposively sampled, and participants were recruited from a broad demographic background with varying years of working experience and designations. The focus group sessions were transcribed verbatim and thematic analysis was performed on their responses. RESULTS: Participants demonstrated limited knowledge of AI. Their perceptions of AI were mixed, recognising its benefits in increasing efficiency and improving patient care, but also aware of its limitations in accuracy and bias. On how patients may perceive AI, participants felt that patients would accept AI if they felt it improves their care but may reject it once they lose trust in it. Expectations wise, participants envisioned several applications in pre-, peri­, and post-procedural workflows including order vetting, patient positioning, language translation, and artefact removal. On radiographers' role and career opportunities, some participants see an opportunity for radiographers to specialise in AI, becoming involved in algorithm development and its clinical implementation. DISCUSSION: Our findings suggest that widespread implementation of AI would require limited knowledge amongst radiographers and current AI limitations to be addressed. While radiographers are positively anticipating the integration of AI into their practices, they should also become actively involved in the development of AI tools such that those they envisioned. This would help align optimal use of AI tools and radiographer role changes. Patients' acceptance and reactions to AI also warrant further research.

Do reproductive hormones control Gulf toadfish pulsatile urea excretion?

Gulf toadfish (Opsanus beta) can excrete the majority of their nitrogenous waste as urea in distinct pulses across their gill. Urea pulses are controlled by cortisol and serotonin (5-HT) and are believed to contain chemical signals that may communicate reproductive and/or social status. The objectives of this study were to determine if reproductive hormones are involved in controlling pulsatile urea excretion, and if toadfish respond to prostaglandins as a chemical signal. Specifically, 11-ketotestosterone (11-KT), estradiol (E2), and the teleost pheromone prostaglandin E2 (PGE2) were investigated. Castration during breeding season did not affect pulsatile urea excretion but serial injections of 11-KT outside of breeding season did result in a 48% reduction in urea pulse size in fish of both sexes. Injections of E2 and PGE2, on the other hand, did not alter urea excretion patterns. Toadfish also did not pulse urea in response to waterborne exposure of PGE2 suggesting that this compound does not serve as a toadfish pheromone alone. Toadfish have significantly higher plasma 5-HT during breeding season compared to the months following breeding season. Future research should focus on the composition of the chemical signal in toadfish and the potential importance of seasonal changes in plasma 5-HT in toadfish pulsatile urea excretion and teleost reproduction in general.

Adult intussusception.

Recurrent abdominal pain is a common and challenging presenting chief complaint in the Emergency Department. Intussusception in adults, although rare, is an important etiology to consider. The diagnosis can often be delayed because of the nonspecific and intermittent nature of symptoms in adults. This report presents the case of a 37-year-old man with multiple Emergency Department visits for abdominal pain and with negative results for prior imaging studies, who was eventually diagnosed with intussusception after 5 years of recurrent symptoms. The case study is followed by a review of the literature regarding the diagnosis and management of intussusception in adults.

Airway management by US and Canadian emergency medicine residents: a multicenter analysis of more than 6,000 endotracheal intubation attempts.

STUDY OBJECTIVE: We determine success rates of endotracheal intubation performed in emergency departments (EDs) by North American emergency medicine residents. METHODS: During 58 months, physicians performing intubations at 31 university-affiliated EDs in 3 nations completed a data form that was entered into the National Emergency Airway Registry 2 database. Included were all patients undergoing endotracheal intubation in the ED. The data form included patients' age, sex, weight, indication for intubation, technique of airway management, names and dosages of all medications used to facilitate intubation, level of training and specialty of the intubator, number of attempts, success or failure, and adverse events. We queried this prospectively gathered, observational data to analyze intubations done by US and Canadian emergency medicine residents. RESULTS: Enrollment was incomplete (eg, 85% at the main study center), so the study sample did not include all consecutive patients. Emergency medicine residents performed 77% (5768/7498; 95% confidence interval [CI] 76% to 78%) of all initial intubation attempts in the United States and Canada. The first intubator was successful in 90% (5,193/5,757; 95% CI 89% to 91%) of cases, including 83% (4,775/5,757; 95% CI 82% to 84%) on the first attempt. Success rates on the first attempt were as follows: postgraduate year 1 = 72% (498/692; 95% CI 68% to 75%), postgraduate year 2 = 82% (2,081/2,544; 95% CI 80% to 83%), postgraduate year 3 = 88% (1,963/2,238; 95% CI 86% to 89%), postgraduate year 4+ = 82% (233/283; 95% CI 77% to 87%), and attending physician = 89% (689/772; 95% CI 87% to 91%). Success rates by the first intubator were as follows: postgraduate year 1 = 80% (553/692; 95% CI 77% to 83%), postgraduate year 2 = 89% (2,272/2,544; 95% CI 88% to 90%), postgraduate year 3 = 94% (2,105/2,238; 95% CI 93% to 95%), postgraduate year 4+ = 93% (263/283; 95% CI 89% to 96%), and attending physician = 98% (755/772; 95% CI 96% to 99%). Rapid sequence intubation technique was used in 78% (4,513/5,768; 95% CI 77% to 79%) of initial attempts: it resulted in 85% (3,843/4,513; 95% CI 84% to 86%) success on the first attempt and 91% (4,117/4,513; 95% CI 90% to 92%) success by the first intubator. The overall rate of cricothyrotomy for all emergency resident intubations was 0.9% (50/5,757; 95% CI 0.6% to 1.1%). When an initial intubator failed, 40% (385/954; 95% CI 37% to 44%) of rescue attempts were performed by emergency medicine residents. Among emergency medicine residents, success on the first rescue attempt was 80% (297/371; 95% CI 76% to 84%), and success by the first rescue intubator was 88% (328/371; 95% CI 85% to 91%). CONCLUSION: Success of initial intubation attempts increased over the first 3 years of residency. This large multicenter study demonstrates the success of airway management by emergency medicine residents in North America. Using rapid-sequence intubation predominantly, emergency medicine residents achieved high levels of success.

Epidemiology of epistaxis in US emergency departments, 1992 to 2001.

STUDY OBJECTIVE: The epidemiology of emergency department (ED) visits for epistaxis is unknown. We use national data to fill this gap and test hypotheses that epistaxis visits are more common with increasing age and in winter. METHODS: We identify ED visit with epistaxis from 10 years of the National Hospital Ambulatory Medical Care Survey. We calculate visit rates by age and other demographic characteristics and assess mode of arrival and disposition. Results are presented with 95% confidence intervals (CIs). RESULTS: From 1992 to 2001, epistaxis occurred at 4,503,000 ED visits, or 0.46% (95% CI 0.41% to 0.51%) of all visits. Per 1,000 population, 1.7 (95% CI 1.5 to 1.9) ED visits for epistaxis occurred annually. The age-related frequency was bimodal, with peaks among those younger than 10 years (4.0 per 1,000 visits) and aged 70 to 79 years (12.0 per 1,000 visits). Most cases (83%; 95% CI 80% to 86%) were atraumatic. Traumatic cases were younger than atraumatic cases (mean age 31 versus 49 years). From December to February, atraumatic epistaxis occurred in 0.50% (95% CI 0.40% to 0.60%) of all visits versus 0.34% (95% CI 0.30% to 0.39%) during nonwinter months. Fifteen percent (95% CI 12% to 18%) of cases arrived by ambulance, and 6% (95% CI 5% to 7%) of patients were hospitalized. CONCLUSION: Epistaxis accounts for about 1 in 200 ED visits in the United States. Although there is an early age peak (age >10 years), the frequency increases from age 20 years onward, with the highest rates in the elderly. Epistaxis visits are more common in the winter. Future efforts to decrease epistaxis visits might focus on education of the elderly and parents of young children about nasal mucosa care and basic approaches to home management.

A triage algorithm for the rapid clinical assessment and management of emergency department patients presenting with chest pain.

This article describes an algorithm for the rapid clinical assessment and evidence-based managemant of patients presenting to the Emergency Department (ED) with chest pain. While broadly applicable, it is specifically designed for use in an ED-based chest pain unit, and incorporates time-sensitive pathways for patients with acute coronary syndromes as well as observation protocols for patients in which the etiology of chest pain is less clear.

The effects of the introduction of a high-nutrient transitional formula on growth and development of very-low-birth-weight infants.

OBJECTIVE: The purpose of this study was to determine the impact of introducing a high-nutrient transitional formula (TF) for use after discharge on the growth and development of premature infants. STUDY DESIGN AND METHODS: This was a cohort study of all surviving infants with a birth weight < or =1250 g admitted to the neonatal intensive care unit between January 1, 1995 and December 31, 1996. Infants with major congenital abnormalities were excluded. There were 180 infants discharged, including 66 on TF and 114 on standard formulas for full-term infants. RESULTS: Use of TF started the week before discharge, and increased from 10% in 1995 to 66% in 1996 (p<0.001). Regression analyses controlling for multiple confounders identified TF as a significant contributor to improved weight at 3 months and length at 18 months. Bayley developmental scores were not affected. CONCLUSION: Introduction of a TF for very-low-birth-weight infants resulted in improved growth after discharge.