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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.

The fish clade Pelagiaria, which includes tunas as its most famous members, evolved remarkable morphological and ecological variety in a setting not generally considered conducive to diversification: the open ocean. Relationships within Pelagiaria have proven elusive due to short internodes subtending major lineages suggestive of rapid early divergences. Using a novel sequence dataset of over 1000 ultraconserved DNA elements (UCEs) for 94 of the 286 species of Pelagiaria (more than 70% of genera), we provide a time-calibrated phylogeny for this widely distributed clade. Some inferred relationships have clear precedents (e.g. the monophyly of ‘core’ Stromateoidei, and a clade comprising ‘Gempylidae’ and Trichiuridae), but others are unexpected despite strong support (e.g. Chiasmodontidae + Tetragonurus ). Relaxed molecular clock analysis using node-based fossil calibrations estimates a latest Cretaceous origin for Pelagiaria, with crown-group families restricted to the Cenozoic. Estimated mean speciation rates decline from the origin of the group in the latest Cretaceous, although credible intervals for root and tip rates are broad and overlap in most cases, and there is higher-than-expected partitioning of body shape diversity (measured as fineness ratio) between clades concentrated during the Palaeocene–Eocene. By contrast, more direct measures of ecology show either no substantial deviation from a null model of diversification (diet) or patterns consistent with evolutionary constraint or high rates of recent change (depth habitat). Collectively, these results indicate a mosaic model of diversification. Pelagiarians show high morphological disparity and modest species richness compared to better-studied fish radiations in contrasting environments. However, this pattern is also apparent in other clades in open-ocean or deep-sea habitats, and suggests that comparative study of such groups might provide a more inclusive model of the evolution of diversity in fishes.

The Cretaceous–Palaeogene (K–Pg) mass extinction is linked to the rapid emergence of ecologically divergent higher taxa (for example, families and orders) across terrestrial vertebrates, but its impact on the diversification of marine vertebrates is less clear. Spiny-rayed fishes (Acanthomorpha) provide an ideal system for exploring the effects of the K–Pg on fish diversification, yet despite decades of morphological and molecular phylogenetic efforts, resolution of both early diverging lineages and enormously diverse subclades remains problematic. Recent multilocus studies have provided the first resolved phylogenetic backbone for acanthomorphs and suggested novel relationships among major lineages. However, these new relationships and associated timescales have not been interrogated using phylogenomic approaches. Here, we use targeted enrichment of >1,000 ultraconserved elements in conjunction with a divergence time analysis to resolve relationships among 120 major acanthomorph lineages and provide a new timescale for acanthomorph radiation. Our results include a well-supported topology that strongly resolves relationships along the acanthomorph backbone and the recovery of several new relationships within six major percomorph subclades. Divergence time analyses also reveal that crown ages for five of these subclades, and for the bulk of the species diversity in the sixth, coincide with the K–Pg boundary, with divergences between anatomically and ecologically distinctive suprafamilial clades concentrated in the first 10 million years of the Cenozoic. Targeted enrichment of >1,000 ultraconserved elements and divergence time analysis resolves relationships among 120 major acanthomorph lineages and provides a new timescale for acanthomorph radiation in the wake of the K–Pg boundary.

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.

One of the moral questions concerning autonomous vehicles (henceforth AVs) is the choice between types that differ in their built-in algorithms for dealing with rare situations of unavoidable lethal collision. It does not appear to be possible to avoid questions about how these algorithms should be designed. We present the results of our study of moral preferences ( N  = 2769) with respect to three types of AVs: (1) selfish, which protects the lives of passenger(s) over any number of bystanders; (2) altruistic, which minimizes the number of casualties, even if this leads to death of passenger(s); and (3) conservative, which abstains from interfering in such situations. We differentiate between scenarios in which participants are to make their decisions privately or publicly, and for themselves or for their offspring. We aim to answer two research questions: (1) whether the public visibility of the choice of an AV type choice make this choice more altruistic and (2) which type of situation makes it more difficult to choose altruistically: when choosing for society as a whole, when choosing only for oneself, or when choosing only for one’s offspring. Our results show that respondents exhibit a preference for an altruistic strategy for AVs and that it is reinforced when signaled to others. The altruistic preference is strongest when applies to everybody else, weaker when it reflects a solely personal choice, and weakest when choosing for one’s own child. We conclude that a public choice is considerably more likely to pressure consumers into accepting a more socially beneficial solution.

In this paper, a special method based on the neural network is presented, which is conveniently used to precompute the steps of numerical integration. This method approximates the behaviour of the numerical integrator with respect to the local truncation error. In other words, it allows the precomputation of the individual steps in such a way that they do not need to be estimated by an algorithm but can be directly estimated by a neural network. Experimental tests were performed on a series of electrical circuits with different component parameters. The method was tested for two integration methods implemented in the simulation program SPICE (Trapez and Gear). For each type of circuit, a custom network was trained. Experimental simulations showed that for well-defined problems with a sufficiently trained network, the method allows in most cases reducing the total number of iteration steps performed by the algorithm during the simulation computation. Applications of this method, drawbacks, and possible further optimizations are also discussed.

GPU cards have been used for scientific calculations for many years. Despite their ever-increasing performance, there are cases where they may still have problems. This article addresses possible performance and memory issues and their solutions that may occur during GPU calculations of iterative algorithms. Specifically, the article focuses on the optimization of transient simulation of extra-large highly nonlinear time-dependent circuits in SPICE-like electronic circuit simulator core enhanced with NVIDIA/CUDA (Compute Unified Device Architecture) interface and iterative Krylov Subspace methods with emphasis on improved accuracy. The article presents procedures for solving problems that may occur during this integration and negatively affect either the simulation speed or the accuracy of the calculation. Finally, a comparison of the implementation of an iterative calculation procedure with the use of GPU cards, calculation by the direct method and calculation on the CPU only is presented.

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 . Graphical abstract

The fish clade Pelagiaria, which includes tunas as its most famous members, evolved remarkable morphological and ecological variety in a setting not generally considered conducive to diversification: the open ocean. Relationships within Pelagiaria have proven elusive due to short internodes subtending major lineages suggestive of rapid early divergences. Using a novel sequence dataset of over 1000 ultraconserved DNA elements (UCEs) for 94 of the 286 species of Pelagiaria (more than 70% of genera), we provide a time-calibrated phylogeny for this widely distributed clade. Some inferred relationships have clear precedents (e.g. the monophyly of ‘core’ Stromateoidei, and a clade comprising ‘Gempylidae’ and Trichiuridae), but others are unexpected despite strong support (e.g. Chiasmodontidae + Tetragonurus). Relaxed molecular clock analysis using node-based fossil calibrations estimates a latest Cretaceous origin for Pelagiaria, with crown-group families restricted to the Cenozoic. Estimated mean speciation rates decline from the origin of the group in the latest Cretaceous, although credible intervals for root and tip rates are broad and overlap in most cases, and there is higher-than-expected partitioning of body shape diversity (measured as fineness ratio) between clades concentrated during the Palaeocene–Eocene. By contrast, more direct measures of ecology show either no substantial deviation from a null model of diversification (diet) or patterns consistent with evolutionary constraint or high rates of recent change (depth habitat). Collectively, these results indicate a mosaic model of diversification. Pelagiarians show high morphological disparity and modest species richness compared to better-studied fish radiations in contrasting environments. However, this pattern is also apparent in other clades in open-ocean or deep-sea habitats, and suggests that comparative study of such groups might provide a more inclusive model of the evolution of diversity in fishes.

We previously demonstrated that the sodium/hydrogen exchanger NHA2, also known as NHEDC2 or SLC9B2, is critical for insulin secretion by β-cells. To gain more insights into the role of NHA2 on systemic glucose homeostasis, we studied the impact of loss of NHA2 during the physiological aging process and in the setting of diet-induced obesity. While glucose tolerance was normal at 2 months of age, NHA2 KO mice displayed a significant glucose intolerance at 5 and 12 months of age, respectively. An obesogenic high fat diet further exacerbated the glucose intolerance of NHA2 KO mice. Insulin levels remained similar in NHA2 KO and WT mice during aging and high fat diet, but fasting insulin/glucose ratios were significantly lower in NHA2 KO mice. Peripheral insulin sensitivity, measured by insulin tolerance tests and hyperinsulinemic euglycemic clamps, was unaffected by loss of NHA2 during aging and high fat diet. High fat diet diminished insulin secretion capacity in both WT and NHA2 KO islets and reduced expression of NHA2 in WT islets. In contrast, aging was characterized by a gradual increase of NHA2 expression in islets, paralleled by an increasing difference in insulin secretion between WT and NHA2 KO islets. In summary, our results demonstrate that loss of the sodium/hydrogen exchanger NHA2 exacerbates obesity- and aging-induced glucose intolerance in mice. Furthermore, our data reveal a close link between NHA2 expression and insulin secretion capacity in islets.