Probabilities of cooperative moves in all 67 symmetric ordinal two-player two-moves games

The symmetric 2x2 one-shot game is one of the simplest and most commonly used representations of strategic conflict. Among others, it includes the prisoner’s dilemma, the game of chicken, the volunteer’s dilemma, and the assurance game. All of these games share three characteristics: (1) both players have to make a single choice between two options; (2) they decide simultaneously; and (3) the payoff structure is symmetric. Typically, social scientists who examine (symmetric) 2x2 one-shot games either focus on one game or compare a small number of such games. There are comparatively few studies which analyzed (symmetric) 2x2 one-shot games in a more comprehensive manner. The goal of the present paper is to initiate research on the strategies people use to play any or all symmetric ordinal two-player two-moves games. We propose comparisons between eight different strategies. As will be shown, this analysis lays the groundwork for many possible follow-up projects

The Role of Certainty in a Two-Person Volunteer’s Dilemma

In the standard volunteer’s dilemma (VoD), a single prosocial act (i.e., volunteering) yields the optimal overall outcome. Whereas the volunteer’s outcome is certain, the defector’s outcome depends on what others do. This research addressed the confounding of prosocial responses with uncertainty avoidance in the standard VoD. In Experiment 1, participants (N = 102) considered 18 hypothetical one-shot two-person VoD scenarios with certain, risky, and uncertain outcomes when volunteering. In Experiment 2, participants (N = 496) considered three hypothetical one-shot two-person VoD scenarios; a certain VoD and two uncertain VoDs of which one had a lower expected collective outcome of volunteering than the certain VoD and the other a higher one. Results suggest that volunteering does not reflect a desire to avoid uncertainty but to maximize expected collective outcomes, reinforcing the assumption that the high volunteering rates we see in a standard VoD are due to social/moral preferences and social projection

Biosynthetic rivalry of o-aminophenol-carboxylic acids initiates production of hemi-actinomycins in Streptomyces antibioticus

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Actinomycins consist of two pentapeptide lactone rings attached to 2-amino-4,6-dimethyl-3-oxo-phenoxazine-1,9-dicarboxylic acid (actinocin). The actinocin moiety is formed through oxidative condensation of two 3-hydroxy-4-methylanthranilic acid (4-MHA) pentapeptide lactones (actinomycin halves) as the last step of actinomycin biosynthesis. We found that feeding of 4-MHA or its putative biogenetic precursor 3-hydroxyanthranilic acid (3-HA) to Streptomyces antibioticus induced formation of different new compounds at the expense of actinomycins. These contain only one pentapeptide lactone ring attached to the β-side of their phenoxazinone ring systems and are formed through premature condensation of the externally added abundant 4-MHA or 3-HA with actinomycin halves. They were termed hemi-actinomycins and C-demethyl-hemi-actinomycins, respectively, which differ from each other in the presence or absence of one or both methyl groups in their phenoxazinone moieties. 3-HA also induces synthesis of various C-demethylactinomycins formed through condensation of actinomycin halves in which 3-HA had been incorporated by the 4-MHA incorporating enzyme in lieu of 4-MHA. 3-HA was not converted to 4-MHA as revealed by its inability to stimulate synthesis of actinomycin or hemi-actinomycin synthesis and thus remained a substrate analogue of 4-MHA rather than its precursor. In contrast to S. antibioticus, actinomycin-producing streptomycetes such as Streptomyces chrysomallus or Streptomyces parvulus do not form hemi-structured actinomycins when fed with 3-HA or 4-MHA. They do not possess the enzyme phenoxazinone synthase (PHS) which in S. antibioticus is present and most probably catalyses premature condensation of abundant 4-MHA or 3-HA with actinomycin halves. Testing hemi-acinomycin IV for drug activity revealed that it intercalates into DNA and inhibits relaxation and supertwisting of DNA by topoisomerase I and DNA-gyrase like actinomycin IV (D). Moreover, it has inhibitory activity on growth of Bacillus subtilis.DFG, EXC 314, Unifying Concepts in Catalysi

Großtagespflegestellen in Niedersachsen : Abschlussbericht des EFRE-Forschungsprojektes

Ein Forschungsteam unter Leitung von Prof. Dr. Romppel hat zwischen 1.8.2011 und 31.7.2014 die Betreuung von Kindern in der Großtagespflege untersucht. Mit der Neufassung des § 24 Abs. 2 SGB VIII zum 1. August 2013 besteht für alle Kinder ab dem 2. Lebensjahr ein Rechtsanspruch auf individuelle Förderung. Der erwarteten wachsenden Nachfrage nach Plätzen für Kinder unter 3 Jahren soll neben dem Krippenausbau auch mit einem Ausbau der Kindertagespflege, in Niedersachsen besonders auch der Großtagespflege, begegnet werden. Großtagespflegestellen sind rechtlich ein gleichwertiges Angebot zur Krippe. Die vorliegende Untersuchung in Niedersachsen geht zum einen der Frage nach, ob die Qualität der pädagogischen Arbeit in den Großtagespflegestellen diesem Anspruch genügen kann. Mit der TAS-R, einem Beobachtungs- und Bewertungsverfahren werden ausgewählte Großtagespflegestellen beurteilt und mit strukturierten Interviews zu ihrer Arbeit befragt. Zudem wird die telefonische und schriftliche Befragung aller Jugendämter Niedersachsens zur Organisation der Fachberatung sowie zur Struktur der finanziellen und fachlichen Unterstützung der Großtagespflegestellen vor Ort vorgestellt. Die Ergebnisse und Empfehlungen für die Verantwortlichen verweisen auf Handlungsbedarf

Comment on Singly Ionizing 100-MeV/amu C⁶⁺+He Collisions with Small Momentum Transfer

In a recent article, Kouzakov suggested that experimental resolution effects can be responsible for discrepancies between measured and calculated fully differential cross sections for the ionization of helium by fast C6+ impact. They further asserted that projectile-coherence effects have no influence on the measured cross sections. In this Comment, we reiterate that the experimental resolution can only explain part of the discrepancies. Furthermore, we note that the conclusion regarding the role of projectile coherence neglects potential interference between first- and higher-order transition amplitudes

Teaching implementation science in a new Master of Science Program in Germany: a survey of stakeholder expectations

Background: Implementation science in healthcare is an evolving discipline in German-speaking countries. In 2015, the Medical Faculty of the University of Heidelberg, Germany, implemented a two-year full-time Master of Science program Health Services Research and Implementation Science. The curriculum introduces implementation science in the context of a broader program that also covers health services research, healthcare systems, research methods, and generic academic skills. Our aim was to assess the expectations of different stakeholder groups regarding the master’s program. Methods: An online survey listing desired competencies of prospective graduates was developed and administered to four groups: national experts in the field (including potential employers of graduates), teaching staff, enrolled students, and prospective students (N = 169). Competencies were extracted from the curriculum’s module handbook. A five-point Likert scale was used for the assessment of 42 specific items. Data were analyzed descriptively. Results: A total of 83 people participated in the survey (response rate 49%). The online survey showed a strong agreement across the groups concerning the desired competencies of graduates. About two-thirds of the listed competencies (27 items) were felt to be crucial or very important by 80% or more of participants, with little difference between stakeholder groups. Of the eight items specifically related to implementation in practice, six were in this category. Knowledge of implementation strategies (90% very important), knowledge of barriers and enablers of implementation (89%), and knowledge of evidence-based practice (89%) were the top priorities. Conclusions: The master’s program is largely orientated towards the desired competencies of graduates according to students, teaching staff, and national experts

Doubly Differential Electron-Emission Spectra in Single and Multiple Ionization of Noble-Gas Atoms by Fast Highly-Charged-Ion Impact

Low-energy electron emission spectra are studied in collisions of 3.6 MeV/amu Au53+ ions with neon and argon atoms for well-defined degrees of target ionization. We calculate doubly differential cross sections as functions of the recoil-ion charge state in the continuum-distorted-wave with eikonal initial-state approximation using a binomial analysis of the total and differential ionization probabilities, and compare them with the present and with previously published experimental data. Very good agreement is found for the single-ionization spectra and for double ionization of neon, while some discrepancies are observed in the spectra for double and triple ionization of argon

Strong-field physics with mid-IR fields

Strong-field physics is currently experiencing a shift towards the use of mid-IR driving wavelengths. This is because they permit conducting experiments unambiguously in the quasi-static regime and enable exploiting the effects related to ponderomotive scaling of electron recollisions. Initial measurements taken in the mid-IR immediately led to a deeper understanding of photo-ionization and allowed a discrimination amongst different theoretical models. Ponderomotive scaling of rescattering has enabled new avenues towards time resolved probing of molecular structure. Essential for this paradigm shift was the convergence of two experimental tools: 1) intense mid-IR sources that can create high energy photons and electrons while operating within the quasi-static regime, and 2) detection systems that can detect the generated high energy particles and image the entire momentum space of the interaction in full coincidence. Here we present a unique combination of these two essential ingredients, namely a 160\~kHz mid-IR source and a reaction microscope detection system, to present an experimental methodology that provides an unprecedented three-dimensional view of strong-field interactions. The system is capable of generating and detecting electron energies that span a six order of magnitude dynamic range. We demonstrate the versatility of the system by investigating electron recollisions, the core process that drives strong-field phenomena, at both low (meV) and high (hundreds of eV) energies. The low energy region is used to investigate recently discovered low-energy structures, while the high energy electrons are used to probe atomic structure via laser-induced electron diffraction. Moreover we present, for the first time, the correlated momentum distribution of electrons from non-sequential double-ionization driven by mid-IR pulses.Comment: 17 pages, 11 figure

Double ionization of helium by electron-impact: complete pictures of the four-body breakup dynamics

The dynamics of He double ionization by 2 keV electron impact is studied experimentally for a momentum transfer of 0.6 a.u. at excess energies of 10 and 40 eV. Complete sets of fivefold differential cross sections are presented for all electron emission angles in coplanar geometry. Contributions beyond the first Born approximation are identified comparing experimental data with first order convergent close-coupling calculations which are in considerably better agreement with the present experiment than with the earlier measurement of Kheifets et al. [J. Phys. B 32, 5047 (1999)]

Simultaneous Projectile-Target Ionization: A Novel Approach to (e, 2e) Experiments on Ions

A kinematically complete experiment for simultaneous ionization of a projectile and target has been performed for 3.6 MeV/u C2+ on He collisions measuring the final vector momenta of the He1+ recoil ion and of two electrons (projectile, target) in coincidence with the emerging C3+ projectile. The feasibility of an event-by-event separation of the various reaction channels, among them the ionization of C2+ by the interaction with a quasifree target electron, is demonstrated in agreement with six-body classical trajectory Monte Carlo calculations, paving the way to kinematically complete electron-ion scattering experiments