Fragmentation transitions in multi-state voter models

Adaptive models of opinion formation among humans can display a fragmentation transition, where a social network breaks into disconnected components. Here, we investigate this transition in a class of models with arbitrary number of opinions. In contrast to previous work we do not assume that opinions are equidistant or arranged on a one-dimensional conceptual axis. Our investigation reveals detailed analytical results on fragmentations in a three-opinion model, which are confirmed by agent-based simulations. Furthermore, we show that in certain models the number of opinions can be reduced without affecting the fragmentation points.Comment: 11 pages, 8 figure

Tragulidae and pecoran ruminants from the latest Middle Miocene (Sarmatian, late Astaracian) of Austria.

One of the richest and most complete European terrestrial vertebrate faunas of late Middle Miocene age (12.2¿12.0 Ma; Gross et al., in press) was found near Gratkorn, at the northeastern realm of the Styrian Basin (Austria). It is one of the rare localities from the Sarmatian sensu stricto (late Serravallian) in the Central Paratethys area with a vertebrate fauna, both high in quality as well as rich in quantity. So far, 62 taxa are recorded, including Euprox furcatus, Micromeryx flourensianus and Dorcatherium naui. This is one of the rare records of Dorcatherium naui older than Vallesian and the oldest finding of the species from the Paratethys realm so far. Up to now, Dorcatherium naui of pre-Vallesian ages have only been described from Przeworno (Poland; Glazek et al., 1971), and Abocador de Can Mata (Spain; Alba et al., 2011), which are of latest Middle Miocene age like Gratkorn. Therefore the latter does not only represent one of the oldest records of Dorcatherium naui but also supports the wide distribution of the taxon already at the latest Middle Miocene. In contrast to the site of Abocador de Can Mata, where Dorcatherium naui is an infrequent element (Alba et al., 2011), the species is abundant at the locality of Gratkorn. Apart from this the larger mammal fauna of Abocadar de Can Mata and Gratkorn is quite similar, except of proboscidean and bovid taxa. While in Abocador de Can Mata Gomphotherium, Deinotherium and bovids are present (Alba et al., 2009), in Gratkorn only Deinotherium giganteum was found until now. Bovids were found in contemporaneous sediments in the eastern Styrian Basin (Gross et al., in press), though. With the material of Gratkorn previous ideas on ecological adaptations in Dorcatherium (Rössner, 2004) are supported and the understanding of the ecological niche of the ¿forest-dweller¿ Dorcatherium is specified. Besides new ideas on dispersal, evolution and ecology of Dorcatherium the locality of Gratkorn also enables an in-depth evaluation of its species separation. The specimens from Gratkorn demonstrate, in comparison with other Material from the Paratethys area, a clear distinction between Dorcatherium crassum and Dorcatherium naui and underline the taxonomic separation of both species as accepted by several authors (e.g. Alba et al., 2011). REFERENCES Alba, D.M. et al. (2009). Middle Miocene vertebrate localities from Abocador de Can Mata (els Hostalets de Pierola, Vallès Penedès Basin, Catalonia, Spain): An update after the 2006-2008 field campaigns. Paleolusitana, 1, 59¿73. Alba, D.M. et al. (2011). Middle Miocene tragulid remains from Abocador de Can Mata: the earliest record of Dorcatherium naui from Western Europe. Geobios, 44, 135-150. Glazek, J. et al. (1971). Miocene vertebrate faunas from Przeworno (Lower Silesia) and their geological setting. Acta Geologica Polonica, 21(3), 473-516. Gross, M. et al. (in press). Gratkorn ¿ A benchmark locality for the continental Sarmatian s. str. of the Central Paratethys. International Journal of Earth Sciences, doi: 10.1007/s00531-010-0615-1. Rössner, G.E. (2004). Community structure and regional patterns in late Early to Middle Miocene Ruminantia of Central Europe. Courier Forschungs-Institut Senckenberg, 249: 91-100.Peer Reviewe

Jumping the Queue:Willingness to Pay for Faster Access to COVID-19 Vaccines in Seven European Countries

Introduction: Given the initial shortage of vaccines to protect against coronavirus disease 2019 (COVID-19), many countries set up priority lists, implying that large parts of the population had to wait. We therefore elicited the willingness to pay (WTP) for access to two hypothetical COVID-19 vaccines. Methods: Respondents were asked how much they would be willing to pay to get an immediate COVID-19 vaccination rather than waiting for one through the public system. We report data collected in January/February 2021 from the European COVID Survey (ECOS) comprising representative samples of the population in Denmark, France, Germany, Italy, Portugal, the Netherlands, and the UK (N = 7068). Results: In total, 73% (68.5%) of respondents were willing to pay for immediate access to a 100% (60%) effective vaccine, ranging from 66.4% (59.4%) in the Netherlands to 83.3% (81.1%) in Portugal. We found a mean WTP of 54.36 euros (median 37 euros) for immediate access to the 100% effective COVID-19 vaccine and 43.83 euros (median 31 euros) for the 60% effective vaccine. The vaccines’ effectiveness, respondents’ age, country of residence, income, health state and well-being were significant determinants of WTP. Willingness to be vaccinated (WTV) was also strongly associated with WTP, with lower WTV being associated with lower WTP. A higher perceived risk of infection, higher health risk, more trust in the safety of vaccines, and higher expected waiting time for the free vaccination were all associated with a higher WTP. Conclusion: We find that most respondents would have been willing to pay for faster access to COVID vaccines (jumping the queue), suggesting welfare gains from quicker access to these vaccines. This is an important result in light of potential future outbreaks and vaccines.</p

Early Miocene gastropod and ectothermic vertebrate remains from the Lesvos Petrified Forest (Greece)

The Lesvos Petrified Forest (western Lesvos, Greece) has long been famous for its plant fossils. Recently, one proboscidean (from the Gavathas locality) and seven micromammalian species (from the Lapsarna locality) were described; these were the first animals to be found in the Early Miocene subtropical forest. For the first time, a fauna of gastropods and ectothermic vertebrates from the Lapsarna locality is now available. This fauna derives from lacustrine sediments under the pyroclastic material that contains the petrified plants. Based on fragmented mollusc remains, isolated fish pharyngeal teeth and utricular otoliths (lapilli), fragmented amphibian vertebrae and a tooth-bearing element, and reptile fragmented dentaries, teeth, osteoderms and vertebrae, the presence of eight freshwater and three terrestrial gastropod species, three freshwater cyprinid species, and two amphibian and five reptile taxa has been confirmed. Stratigraphical and radiometric data suggest an age older than 18.4 ± 0.5 Ma (latest Early Miocene), in good agreement with the faunal composition. This paper is the first report of the concurrent presence of three cyprinid fish species in a Greek Early Miocene locality, as well as the first documentation of an Early Miocene proteid amphibian in southeastern Europe. The present findings represent one of the best- documented Early Miocene gastropod and fish faunas in the Aegean/southern Balkans, thus adding to our knowledge of Early Miocene amphibians and reptiles from that region and providing valuable information on the local subtropical ecosystem

Extraction of the frequency moments of spectral densities from imaginary-time correlation function data

We introduce an exact framework to compute the positive frequency moments $M^{(\alpha)}(\mathbf{q})=\braket{\omega^\alpha}$ of different dynamic properties from imaginary-time quantum Monte Carlo data. As a practical example, we obtain the first five moments of the dynamic structure factor $S(\mathbf{q},\omega)$ of the uniform electron gas at the electronic Fermi temperature based on \emph{ab initio} path integral Monte Carlo simulations. We find excellent agreement with known sum rules for $\alpha=1,3$, and, to our knowledge, present the first results for $\alpha=2,4,5$. Our idea can be straightforwardly generalized to other dynamic properties such as the single-particle spectral function $A(\mathbf{q},\omega)$, and will be useful for a number of applications, including the study of ultracold atoms, exotic warm dense matter, and condensed matter systems

A Human-Oriented Term Rewriting System

© Springer Nature Switzerland AG 2019. We introduce a fully automatic system, implemented in the Lean theorem prover, that solves equality problems of everyday mathematics. Our overriding priority in devising the system is that it should construct proofs of equality in a way that is similar to that of humans. A second goal is that the methods it uses should be domain independent. The basic strategy of the system is to operate with a subtask stack: whenever there is no clear way of making progress towards the task at the top of the stack, the program finds a promising subtask, such as rewriting a subterm, and places that at the top of the stack instead. Heuristics guide the choice of promising subtasks and the rewriting process. This makes proofs more human-like by breaking the problem into tasks in the way that a human would. We show that our system can prove equality theorems simply, without having to preselect or orient rewrite rules as in standard theorem provers, and without having to invoke heavy duty tools for performing simple reasoning

Safety and Efficacy of Itraconazole Compared to Amphotericin B as Empirical Antifungal Therapy for Neutropenic Fever in Patients with Haematological Malignancy

Safety, tolerability and efficacy of itraconazole and amphotericin B (AMB) were compared for empirical antifungal treatment of febrile neutropenic cancer patients. Patients and Methods: In an open, randomised study, 162 patients with at least 72 h of antimicrobial treatment received either intravenous followed by oral itraconazole suspension or intravenous AMB for a maximum of 28 days. Permanent discontinuation of study medication due to any adverse event was the primary safety parameter. Efficacy parameters included response and success rate for both treatment groups. Results: Significantly fewer itraconazole patients discontinued treatment due to any adverse event (22.2 vs. 56.8% AMB; p < 0.0001). The main reason for discontinuation was a rise in serum creatinine (1.2% itraconazole vs. 23.5% AMB). Renal toxicity was significantly higher and more drug-related adverse events occurred in the AMB group. Intention-to-treat (ITT) analysis showed favourable efficacy for itraconazole: response and success rate were both significantly higher than for AMB (61.7 vs. 42% and 70.4 vs. 49.3%, both p < 0.0001). Treatment failure was markedly reduced in itraconazole patients (25.9 vs. 43.2%), largely due to the better tolerability. Conclusions: Itraconazole was tolerated significantly better than conventional AMB and also showed advantages regarding efficacy. This study confirms the role of itraconazole as a useful and safe agent in empirical antifungal therapy of febrile neutropenic cancer patients.Hintergrund: Es wurden die Sicherheit, Verträglichkeit und Wirksamkeit von Itraconazol und Amphotericin B (AMB) in der antimykotischen Therapie der persistierend febrilen Neutropenie verglichen. Patienten und Methoden: In einer offenen, randomisierten Studie erhielten 162 Patienten mit mindestens 72-stündiger antibiotischer Therapie entweder Itraconazol (erst intravenös, dann oral) oder AMB (intravenös) für maximal 28 Tage. Primärer Sicherheitsparameter war die dauerhafte Unterbrechung der Studienmedikation aufgrund von Nebenwirkungen. Die Wirksamkeitsparameter umfassten die Ansprech- und Erfolgsrate für beide Behandlungsgruppen. Ergebnisse: Signifikant weniger Itraconazol-Patienten brachen die Behandlung wegen Nebenwirkungen ab (22,2 vs. 56,8% AMB; p < 0,0001). Hauptursache für Studienabbrüche war der Anstieg des Serum-Kreatinin-Spiegels (1,2% Itraconazol vs. 23,5% AMB). Nephrotoxische und weitere Nebenwirkungen traten im AMB-Studienarm signifikant häufiger auf. Intention-to-Treat (ITT)-Analysen zeigten eine bessere Wirksamkeit von Itraconazol: Ansprech- und Erfolgsrate waren signifikant höher als unter AMB (61,7 vs. 42% und 70,4 vs. 49,3%, beide p < 0,0001). Behandlungsversagen trat bei Itraconazol-Patienten merklich weniger auf (25,9 vs. 43,2%). Schlussfolgerungen: Die Verträglichkeit von Itraconazol war signifikant höher als beim herkömmlichen AMB. Itraconazol zeigte ebenfalls Vorteile in der Wirksamkeit. Diese Studie bestätigt die Rolle von Itraconazol als sinnvolles und sicheres Medikament in der empirischen antimykotischen Therapie von fiebrigen neutropenischen Tumorpatienten.Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich