1,030 research outputs found
The destructive effect of human stupidity: a revision of Cipolla’s fundamental laws
In this work, we analyze an evolutionary game that incorporates the ideas presented by Carlo Cipolla in “The fundamental laws of human stupidity”. The game considers four strategies, three of them are inherent to the player behavior and can evolve via imitation dynamics, while the fourth one is associated with an eventual behavior that can be adopted by any player at any time with a certain probability. This fourth strategy corresponds to what Cipolla calls a stupid person. The probability of behaving stupidly acts as a parameter that induces a phase transition in the steady distribution of strategies among the population.Fil: Bárcenas, Donny R.. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; ArgentinaFil: Kuperman, Joel. Universidad Nacional de Córdoba. Facultad de Matemática, Astronomía y Física; ArgentinaFil: Kuperman, Marcelo Nestor. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Bariloche); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; Argentin
Cultural propagation on social networks
In this work we present a model for the propagation of culture on networks of
different topology and by considering different underlying dynamics. We extend
a previous model proposed by Axelrod by letting a majority govern the dynamics
of changes. This in turn allows us to define a Lyapunov functional for the
system.Comment: 8 pages, 9 figures include
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Certainty in ascending sensory signals - The unexplored driver of analgesic placebo response.
Previous frameworks have failed to adequately explain the observed correlation between within-subject variability in pain reporting and analgesic placebo response. These relationships have been observed in both clinical and experimental setups. Within-subject variability of clinical pain scores is traditionally assessed based on daily pain diaries collected during the pre-intervention stage. Experimental variability can be assessed by the Focused Analgesia Selection Test (FAST), which calculates the relationship between noxious stimuli administrated at various intensities and pain reports. The variability, either clinical or experimental, has been shown to predict the placebo response. In explaining the placebo response, Bayesian Brain Hypothesis (BBH) posits that pain perception (posterior), is composed of certainty (precision) of expectations (priors due to belief or conditioning) and incoming sensory information (likelihood), with the bulk of research focused on the precision of priors. Virtually all placebo analgesia research has focused on the priors and their certainty, rather than on the certainty of the likelihood, mainly because it cannot be assessed directly. We propose that the within-subject variability, as encapsulated by the FAST, is a proxy for certainty in (or, precision of) ascending sensory signals, and our results suggest that it could not only be assessed, but also manipulated. If true, our hypothesis will facilitate new lines of research and could potentially promote precision analgesic medicine by use of variability of pain scores as a diagnostic method to identify pain patients who will benefit from specific treatments
Development and Evaluation of the Eastern Pennsylvania and Delaware Geriatric Education Center’s (EPaD GEC) Geriatric Oncology Online Toolkit
Older adults have higher cancer rates than younger adults. Treating geriatric cancer patients is a challenge because they present with comorbidities, poly-pharmacy, physical frailty, and/or cognitive impairment. The interprofessional oncology treatment team may not be adequately trained to meet the special needs of geriatric cancer patients. The EPaD GEC focuses on interprofessional geriatric education targeting students, faculty and practitioners by developing and disseminating interprofessional geriatric training programs, including self-directed online learning modules. The Geriatric Oncology Care Module focuses on specialized considerations in the treatment/care of older cancer patients. The purpose of this project is to develop a Geriatric Oncology toolkit as a companion to the online learning module, and assess its benefits for enhancement of interdisciplinary health providers’ knowledge and ability to assist older adult cancer patients and their families. Specific aims are to evaluate the organizational utility and content of the toolkit from the perspective of healthcare providers and student and its ability to improve their knowledge of resources for older cancer patients/families. A qualitative and quantitative survey was administered to a convenience sample of 23 interprofessional healthcare students and practitioners. Results using Survey Monkey demonstrate that practitioners from geriatric-related specialties are more familiar with the content, that the toolkit can improve efficiency and effectiveness, and an overall satisfaction with organizational utility and content. Results support the following recommendations to the EPaD GEC: use of toolkit as a training tool for residents and fellows in Oncology, Geriatrics, and Family Medicine, and targeted dissemination to practitioners in the same sub-specialties. There is a continuing need to educate interprofessional health care providers on the specialized needs of older cancer patients.
45 PowerPoint slides (no audio)
Correlation effects in a simple model of small-world network
We analyze the effect of correlations in a simple model of small world
network by obtaining exact analytical expressions for the distribution of
shortest paths in the network. We enter correlations into a simple model with a
distinguished site, by taking the random connections to this site from an Ising
distribution. Our method shows how the transfer matrix technique can be used in
the new context of small world networks.Comment: 10 pages, 3 figure
Comparison of voter and Glauber ordering dynamics on networks
We study numerically the ordering process of two very simple dynamical models
for a two-state variable on several topologies with increasing levels of
heterogeneity in the degree distribution. We find that the zero-temperature
Glauber dynamics for the Ising model may get trapped in sets of partially
ordered metastable states even for finite system size, and this becomes more
probable as the size increases. Voter dynamics instead always converges to full
order on finite networks, even if this does not occur via coherent growth of
domains. The time needed for order to be reached diverges with the system size.
In both cases the ordering process is rather insensitive to the variation of
the degreee distribution from sharply peaked to scale-free.Comment: 12 pages, 12 figure
Effects of Mass Media and Cultural Drift in a Model for Social Influence
In the context of an extension of Axelrod's model for social influence, we
study the interplay and competition between the cultural drift, represented as
random perturbations, and mass media, introduced by means of an external
homogeneous field. Unlike previous studies [J. C. Gonz\'alez-Avella {\it et
al}, Phys. Rev. E {\bf 72}, 065102(R) (2005)], the mass media coupling proposed
here is capable of affecting the cultural traits of any individual in the
society, including those who do not share any features with the external
message. A noise-driven transition is found: for large noise rates, both the
ordered (culturally polarized) phase and the disordered (culturally fragmented)
phase are observed, while, for lower noise rates, the ordered phase prevails.
In the former case, the external field is found to induce cultural ordering, a
behavior opposite to that reported in previous studies using a different
prescription for the mass media interaction. We compare the predictions of this
model to statistical data measuring the impact of a mass media vasectomy
promotion campaign in Brazil.Comment: 10 pages, 3 figures; minor changes; added references. To appear in
IJMP
12/15-Lipoxygenase Is an Interleukin-13 and Interferon-γ Counterregulated-Mediator of Allergic Airway Inflammation
Interleukin-13 and interferon-γ are important effectors of T-helper cells. Interleukin-13 increases expression of the arachidonic acid-metabolizing enzyme, 15-lipoxygenase-1, in a variety of cell types. 15-lipoxygenase-1 is dramatically elevated in the airways of subjects with asthma. Studies in animals indicate that 15-lipoxygenase-1 contributes to the development of allergic airway inflammation but is protective in some other forms of inflammation. We tested the hypothesis that the ability of interleukin-13 and interferon-γ to counterregulate allergic airway inflammation was potentially mediated by counterregulation of 12/15-lipoxygenase, the mouse ortholog of 15-lipoxygenase-1. The airways of mice were treated with interleukin-13 or interferon-γ one day prior to each of the four allergen exposures. Interleukin-13 augmented and interferon-γ inhibited allergic airway inflammation independently of systemic IgE and mucosal IgA responses but in association with counterregulation of 12/15-lipoxygenase. Interleukin-13 and interferon-γ counterregulate 12/15-lipoxygenase potentially contributing to the effects of these cytokines on allergic airway inflammation
Opinion and community formation in coevolving networks
In human societies opinion formation is mediated by social interactions,
consequently taking place on a network of relationships and at the same time
influencing the structure of the network and its evolution. To investigate this
coevolution of opinions and social interaction structure we develop a dynamic
agent-based network model, by taking into account short range interactions like
discussions between individuals, long range interactions like a sense for
overall mood modulated by the attitudes of individuals, and external field
corresponding to outside influence. Moreover, individual biases can be
naturally taken into account. In addition the model includes the opinion
dependent link-rewiring scheme to describe network topology coevolution with a
slower time scale than that of the opinion formation. With this model
comprehensive numerical simulations and mean field calculations have been
carried out and they show the importance of the separation between fast and
slow time scales resulting in the network to organize as well-connected small
communities of agents with the same opinion.Comment: 10 pages, 5 figures. New inset for Fig. 1 and references added.
Submitted to Physical Review
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