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The interrelationships of the three major dinosaur clades (Theropoda, Sauropodomorpha, and Ornithischia) have come under increased scrutiny following the recovery of conflicting phylogenies by a large new character matrix and its extensively modified revision. Here, we use tools derived from recent phylogenomic studies to investigate the strength and causes of this conflict. Using maximum likelihood as an overarching framework, we examine the global support for alternative hypotheses as well as the distribution of phylogenetic signal among individual characters in both the original and rescored dataset. We find the three possible ways of resolving the relationships among the main dinosaur lineages (Saurischia, Ornithischiformes, and Ornithoscelida) to be statistically indistinguishable and supported by nearly equal numbers of characters in both matrices. While the changes made to the revised matrix increased the mean phylogenetic signal of individual characters, this amplified rather than reduced their conflict, resulting in greater sensitivity to character removal or coding changes and little overall improvement in the ability to discriminate between alternative topologies. We conclude that early dinosaur relationships are unlikely to be resolved without fundamental changes to both the quality of available datasets and the techniques used to analyze them. [ABSTRACT FROM AUTHOR]

Background: Providing palliative care at the end of life (EOL) in intensive care units (ICUs) seems to be modified during the COVID-19 pandemic with potential burden of moral distress to health care providers (HCPs). We seek to assess the practice of EOL care during the COVID-19 pandemic in ICUs in the Czech Republic focusing on the level of moral distress and its possible modifiable factors.Methods: Between 16 June 2021 and 16 September 2021, a national, cross-sectional study in intensive care units (ICUs) in Czech Republic was performed. All physicians and nurses working in ICUs during the COVID-19 pandemic were included in the study. For questionnaire development ACADEMY and CHERRIES guide and checklist were used. A multivariate logistic regression model was used to analyse possible modifiable factors of moral distress.Results: In total, 313 HCPs (14.5% out of all HCPs who opened the questionnaire) fully completed the survey. Results showed that 51.8% (n = 162) of respondents were exposed to moral distress during the COVID-19 pandemic. 63.1% (n = 113) of nurses and 71.6% of (n = 96) physicians had experience with the perception of inappropriate care. If inappropriate care was perceived, a higher chance for the occurrence of moral distress for HCPs (OR, 1.854; CI, 1.057-3.252; p = 0.0312) was found. When patients died with dignity, the chance for moral distress was lower (OR, 0.235; CI, 0.128-0.430; p < 0.001). The three most often reported differences in palliative care practice during pandemic were health system congestion, personnel factors, and characteristics of COVID-19 infection.Conclusions: HCPs working at ICUs experienced significant moral distress during the COVID-19 pandemic in the Czech Republic. The major sources were perceiving inappropriate care and dying of patients without dignity. Improvement of the decision-making process and communication at the end of life could lead to a better ethical and safety climate.Trial Registration: NCT04910243 . [ABSTRACT FROM AUTHOR]

Changes in speciation and extinction rates are key to the dynamics of clade diversification, but attempts to infer them from phylogenies of extant species face challenges. Methods capable of synthesizing information from extant and fossil species have yielded novel insights into diversification rate variation through time, but little is known about their behavior when analyzing entirely extinct clades. Here, we use empirical and simulated data to assess how two popular methods, PyRate and Fossil BAMM, perform in this setting. We inferred the first tip-dated trees for ornithischian dinosaurs and combined them with fossil occurrence data to test whether the clade underwent an end-Cretaceous decline. We then simulated phylogenies and fossil records under empirical constraints to determine whether macroevolutionary and preservation rates can be teased apart under paleobiologically realistic conditions. We obtained discordant inferences about ornithischian macroevolution including a long-term speciation rate decline (BAMM), mostly flat rates with a steep diversification drop (PyRate) or without one (BAMM), and episodes of implausibly accelerated speciation and extinction (PyRate). Simulations revealed little to no conflation between speciation and preservation, but yielded spuriously correlated speciation and extinction estimates while time-smearing tree-wide shifts (BAMM) or overestimating their number (PyRate). Our results indicate that the small phylogenetic data sets available to vertebrate paleontologists and the assumptions made by current model-based methods combine to yield potentially unreliable inferences about the diversification of extinct clades. We provide guidelines for interpreting the results of the existing approaches in light of their limitations and suggest how the latter may be mitigated. [BAMM; diversification; fossils; macroevolutionary rates; Ornithischia; PyRate.] [ABSTRACT FROM AUTHOR]

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