203 research outputs found
Density-Functional-Theory Calculations of Matter in Strong Magnetic Fields: I. Atoms and Molecules
We present new ab initio calculations of the electronic structure of various
atoms and molecules in strong magnetic fields ranging from B=10^12 G to 2x10^15
G, appropriate for radio pulsars and magnetars. For these field strengths, the
magnetic forces on the electrons dominate over the Coulomb forces, and to a
good approximation the electrons are confined to the ground Landau level. Our
calculations are based on the density functional theory, and use a local
magnetic exchange-correlation function which is tested to be reliable in the
strong field regime. Numerical results of the ground-state energies are given
for H_N (up to N=10), He_N (up to N=8), C_N (up to N=5) and Fe_N (up to N=3),
as well as for various ionized atoms. Fitting formulae for the B-dependence of
the energies are also given. In general, as N increases, the binding energy per
atom in a molecule, |E_N|/N, increases and approaches a constant value. For all
the field strengths considered in this paper, hydrogen, helium, and carbon
molecules are found to be bound relative to individual atoms (although for B
less than a few x 10^12 G, the relative binding between C and C_2 is small).
Iron molecules are not bound at B<10^13 G, but become energetically more
favorable than individual atoms at larger field strengths.Comment: 19 pages, 4 figures. Minor changes, figure omissions. Phys. Rev. A in
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When helping is risky: the behavioral and neurobiological tradeoff of social and risk preferences
This is the final version. Available on open access from SAGE Publications via the DOI in this recordData availability: Methods and data for Study 1 can be accessed
at https://dataverse.nl/dataset.xhtml?persistentId=doi:10.34894/9UIPH4; for Study 2, please contact
dr. M.J. Crockett. The authors declare no conflict of interest.Helping other people can entail risks for the helper. For example, when treating infectious patients, medical volunteers risk their own health. In such situations, decisions to help should depend on the individual’s valuation of others’ well-being (social preferences) and the degree of personal risk the individual finds acceptable (risk preferences). We investigated how these distinct preferences are psychologically and neurobiologically integrated when helping is risky. We used incentivized decision-making tasks (Study 1; N = 292 adults) and manipulated dopamine and norepinephrine levels in the brain by administering methylphenidate, atomoxetine, or a placebo (Study 2; N = 154 adults). We found that social and risk preferences are independent drivers of risky helping. Methylphenidate increased risky helping by selectively altering risk preferences rather than social preferences. Atomoxetine influenced neither risk preferences nor social preferences and did not affect risky helping. This suggests that methylphenidate-altered dopamine concentrations affect helping decisions that entail a risk to the helper.Netherlands Science FoundationUniversity of AmsterdamWellcome TrustAcademy of Medical SciencesOxford Martin SchoolMedical Research Council (MRC)National Institute for Health Research (NIHR
A dispositional approach to psychological climate: relationships between interpersonal harmony motives and psychological climate for communication safety
This study examined the dispositional antecedents of a climate at the individual level, psychological climate for communication safety. The impact of two interpersonal harmony motives, harmony enhancement and disintegration avoidance, on psychological climate for communication safety, innovative performance and the moderated mediated processes associated with job autonomy were examined in a survey study in China. Results showed that harmony enhancement was positively related to innovative performance through psychological climate for communication safety. Moreover, job autonomy moderated the relationship between harmony motives and psychological climate for communication safety. Harmony enhancement was more strongly associated with psychological climate for communication safety when job autonomy was low. The relationship between disintegration avoidance and psychological climate for communication safety was positive when job autonomy was high, but negative when job autonomy was low. Conditional indirect effects consistent with these interaction effects were also found
Shared communication processes within healthcare teams for rare diseases and their influence on healthcare professionals' innovative behavior and patient satisfaction
<p>Abstract</p> <p>Background</p> <p>A rare disease is a pattern of symptoms that afflicts less than five in 10,000 patients. However, as about 6,000 different rare disease patterns exist, they still have significant epidemiological relevance. We focus on rare diseases that affect multiple organs and thus demand that multidisciplinary healthcare professionals (HCPs) work together. In this context, standardized healthcare processes and concepts are mainly lacking, and a deficit of knowledge induces uncertainty and ambiguity. As such, individualized solutions for each patient are needed. This necessitates an intensive level of innovative individual behavior and thus, adequate idea generation. The final implementation of new healthcare concepts requires the integration of the expertise of all healthcare team members, including that of the patients. Therefore, knowledge sharing between HCPs and shared decision making between HCPs and patients are important. The objective of this study is to assess the contribution of shared communication and decision-making processes in patient-centered healthcare teams to the generation of innovative concepts and consequently to improvements in patient satisfaction.</p> <p>Methods</p> <p>A theoretical framework covering interaction processes and explorative outcomes, and using patient satisfaction as a measure for operational performance, was developed based on healthcare management, innovation, and social science literature. This theoretical framework forms the basis for a three-phase, mixed-method study. Exploratory phase I will first involve collecting qualitative data to detect central interaction barriers within healthcare teams. The results are related back to theory, and testable hypotheses will be derived. Phase II then comprises the testing of hypotheses through a quantitative survey of patients and their HCPs in six different rare disease patterns. For each of the six diseases, the sample should comprise an average of 30 patients with six HCP per patient-centered healthcare team. Finally, in phase III, qualitative data will be generated via semi-structured telephone interviews with patients to gain a deeper understanding of the communication processes and initiatives that generate innovative solutions.</p> <p>Discussion</p> <p>The findings of this proposed study will help to elucidate the necessity of individualized innovative solutions for patients with rare diseases. Therefore, this study will pinpoint the primary interaction and communication processes in multidisciplinary teams, as well as the required interplay between exploratory outcomes and operational performance. Hence, this study will provide healthcare institutions and HCPs with results and information essential for elaborating and implementing individual care solutions through the establishment of appropriate interaction and communication structures and processes within patient-centered healthcare teams.</p
Social Expectations Bias Decision-Making in Uncertain Inter-Personal Situations
Understanding the role that social cues have on interpersonal choice, and their susceptibility to contextual effects, is of core importance to models of social decision-making. Language, on the other hand, is one of the main means of communication during social interactions in our culture. The present experiments tested whether positive and negative linguistic descriptions of alleged partners in a modified Ultimatum Game biased decisions made to the same set of offers, and whether the contextual uncertainty of the game modulated this biasing effect. The results showed that in an uncertain context, the same offers were accepted with higher probability when they were preceded by positive rather than by negative valenced trait-words. Participants also accepted fair offers with higher probability than unfair offers, but this effect did not interact with the valence of the social descriptive words. In addition, the speed of the decision was affected by valence: acceptance choices were faster when they followed a positive adjective, whereas rejection responses were faster after a negative-valenced word. However, these effects were highly reduced when the uncertainty was eliminated from the game. This suggests that positive and negative relevant social information can bias decisions made to the same pieces of evidence during interpersonal interactions, but that this mainly takes place when the uncertainty associated with the choices is high
U-Shaped Relation between Plasma Oxytocin Levels and Behavior in the Trust Game
10.1371/journal.pone.0051095PLoS ONE712
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