Month: March 2021

SECOND WORKSHOP ON STOCHASTIC MODELS IN ECOLOGY AND BIOLOGY – VIRTUAL + VENICE

The workshop will virtually take place from the European Center of Living Technology in Venice on 22-25 June 2021. 

Confirmed Invited Speakers are: 

 · Rosalind Allen, University of Edinburgh 

 · Eric Dykeman, University of York 

 · Daniel Fisher, Standford University 

 · Nigel Goldenfeld, University of Illinois at UC 

 · Susan Holmes, Standford University 

 · Terry Hwa, UC San Diego 

 · Eleni Katifori, University of Pennsylvania 

 · David Nelson, Harvard University 

 · Alvaro Sanchez, Yale University 

 · Agnese Seminara, CNRS, Institut de physique de Nice 

 · Corina Tarnita, Princeton University 

 · Amandine Veber, CNRS and Univ. of Paris 

20 free waiver for Ph.D students, special discount for publishing in related joint special issue of #Entropy & #Life, prize for best poster and best talk!

Living systems are characterized by the emergence of recurrent dynamical patterns at all scales of magnitude. Self-organized behaviors are observed both in large communities of microscopic components – like neural oscillations and gene network activity – as well as on larger levels – as predator-prey equilibria to name a few. Such regularities are deemed to be universal in the sense they are due to common mechanisms, independent of the details of the system. This belief justifies investigation through quantitative models able to grasp key features while disregarding inessential complications. The attempt of modeling such complex systems leads naturally to consider large families of microscopic identical units. Complexity and self-organization then arise on a macroscopic scale from the dynamics of these minimal components that evolve coupled by interaction terms. Within this scenario, probability theory and statistical mechanics come into play very soon.
The aim of this conference is to bring together scientists with different backgrounds (maths, biology, physics and computing, theoreticians along with experimentalists), interested in macroecology, microbial ecology and evolutionary biology, to discuss important and recent research topics in these areas as well as exchange methods and ideas. The style of the conference will purposely be informal so as to encourage discussions.

Read the full article at: liphlab.github.io

Mutual anticipation can contribute to self-organization in human crowds

Hisashi Murakami, Claudio Feliciani, Yuta Nishiyama and Katsuhiro Nishinari

Science Advances 17 Mar 2021:
Vol. 7, no. 12, eabe7758
DOI: 10.1126/sciadv.abe7758

Human crowds provide paradigmatic examples of collective behavior emerging through self-organization. Understanding their dynamics is crucial to help manage mass events and daily pedestrian transportation. Although recent findings emphasized that pedestrians’ interactions are fundamentally anticipatory in nature, whether and how individual anticipation functionally benefits the group is not well understood. Here, we show the link between individual anticipation and emergent pattern formation through our experiments of lane formation, where unidirectional lanes are spontaneously formed in bidirectional pedestrian flows. Manipulating the anticipatory abilities of some of the pedestrians by distracting them visually delayed the collective pattern formation. Moreover, both the distracted pedestrians and the nondistracted ones had difficulties avoiding collisions while navigating. These results imply that avoidance maneuvers are normally a cooperative process and that mutual anticipation between pedestrians facilitates efficient pattern formation. Our findings may influence various fields, including traffic management, decision-making research, and swarm dynamics.

Read the full article at: advances.sciencemag.org

The effective graph reveals redundancy, canalization, and control pathways in biochemical regulation and signaling

Alexander J. Gates, Rion Brattig Correia, Xuan Wang, and Luis M. Rocha

PNAS March 23, 2021 118 (12) e2022598118

Many biological networks are modeled with multivariate discrete dynamical systems. Current theory suggests that the network of interactions captures salient features of system dynamics, but it misses a key aspect of these networks: some interactions are more important than others due to dynamical redundancy and nonlinearity. This unequivalence leads to a canalized dynamics that differs from constraints inferred from network structure alone. To capture the redundancy present in biochemical regulatory and signaling interactions, we present the effective graph, an experimentally validated mathematical framework that synthesizes both structure and dynamics in a weighted graph representation of discrete multivariate systems. Our results demonstrate the ubiquity of redundancy in biology and provide a tool to increase causal explainability and control of biochemical systems.

Read the full article at: www.pnas.org

Shifting attention to accuracy can reduce misinformation online

Gordon Pennycook, Ziv Epstein, Mohsen Mosleh, Antonio A. Arechar, Dean Eckles & David G. Rand
Nature (2021)

In recent years, there has been a great deal of concern about the proliferation of false and misleading news on social media1–4. Academics and practitioners alike have asked why people share such misinformation, and sought solutions to reduce the sharing of misinformation5–7. Here, we attempt to address both of these questions. First, we find that the veracity of headlines has little effect on sharing intentions, despite having a large effect on judgments of accuracy. This dissociation suggests that sharing does not necessarily indicate belief. Nonetheless, most participants say it is important to share only accurate news. To shed light on this apparent contradiction, we carried out four survey experiments and a field experiment on Twitter; the results show that subtly shifting attention to accuracy increases the quality of news that people subsequently share. Together with additional computational analyses, these findings indicate that people often share misinformation because their attention is focused on factors other than accuracy—and therefore they fail to implement a strongly held preference for accurate sharing. Our results challenge the popular claim that people value partisanship over accuracy8,9, and provide evidence for scalable attention-based interventions that social media platforms could easily implement to counter misinformation online. Surveys and a field experiment with Twitter users show that prompting people to think about the accuracy of news sources increases the quality of the news that they share online.

Read the full article at: www.nature.com