Minimal model of self-replicating nanocells: a physically embodied information-free scenario

The building of minimal self-reproducing systems with a physical embodiment (generically called protocells) is a great challenge, with implications for both theory and applied sciences. Although the classical view of a living protocell assumes that it includes information-carrying molecules as an essential ingredient, a dividing cell-like structure can be built from a metabolism-container coupled system, only. An example of such a system, modeled with dissipative particle dynamics, is presented here. This article demonstrates how a simple coupling between a precursor molecule and surfactant molecules forming micelles can experience a growth-division cycle in a predictable manner, and analyzes the influence of crucial parameters on this replication cycle. Implications of these results for origins of cellular life and living technology are outlined.Comment: 9 pages, 10 figure

A wider view of assessments of ecosystem services in coastal areas : the perspective of social-ecological complexity

This research was carried out under the framework of POLICLIMA project (CSO2016-76842-C2-1-R). The first author was supported by a PhD grant (FI-2017) from the Agència de Gestió d'Ajuts Universitaris. The second author was supported by Ramón y Cajal contract (RYC-2013-13392) from the Ministerio de Economía y Competitividad.Through complex interactions and feedback processes between coastal ecological and social components at different temporal and spatial scales, coastal environments coproduce a range of ecosystem services (ES) and benefit different social groups. In these highly populated areas, multiple actors, interests, and activities coexist, leading to intensified conflicts between stakeholders. The research presented here aims to understand how coastal social-ecological complexity is studied within coastal ES literature. A systematic review of the literature consisting of 199 manuscripts was performed using the PRISMA method (Preferred Reporting Items for Systematic Reviews and Meta-Analyses). The results show that coastal ES research has been focused on understanding ecological processes for ES provision and value. Hence, coastal ES studies fall short of considering the social components and social-ecological interactions of coastal systems: ES flows, demand, coproduction, power relations, institutions and governance, temporal and spatial scales, value pluralism, uncertainty, and human well-being multidimensions and distribution. The partial integration of social-ecological complexity within coastal ES research limits coastal ES management because nonlinear interactions among social and ecological components are not well understood, particularly stakeholders' relations, their roles, and the links to ES. Finally, we propose a conceptual framework that integrates the gaps identified during the review. The framework places coproduction and power relations as the core factors of assessments of coastal ES, as means to understand complex, nonlinear social-ecological interactions and feedback processes. Hence, it also provides necessary tools to address normative issues of coastal management such as control, access, trade-offs, and benefits

Red Queen Coevolution on Fitness Landscapes

Species do not merely evolve, they also coevolve with other organisms. Coevolution is a major force driving interacting species to continuously evolve ex- ploring their fitness landscapes. Coevolution involves the coupling of species fit- ness landscapes, linking species genetic changes with their inter-specific ecological interactions. Here we first introduce the Red Queen hypothesis of evolution com- menting on some theoretical aspects and empirical evidences. As an introduction to the fitness landscape concept, we review key issues on evolution on simple and rugged fitness landscapes. Then we present key modeling examples of coevolution on different fitness landscapes at different scales, from RNA viruses to complex ecosystems and macroevolution.Comment: 40 pages, 12 figures. To appear in "Recent Advances in the Theory and Application of Fitness Landscapes" (H. Richter and A. Engelbrecht, eds.). Springer Series in Emergence, Complexity, and Computation, 201

Sur certaines relations entre les intégrales trajectorielles et l'opérateur de translation et son dual dans l'espace de Poisson canonique

We study the relationship between the translation operator, its dual and the pathwise integral on the Poisson space with weak conditions on the processes

Pauli graphs, Riemann hypothesis, Goldbach pairs

Let consider the Pauli group $\mathcal{P}_q=$ with unitary quantum generators $X$ (shift) and $Z$ (clock) acting on the vectors of the $q$-dimensional Hilbert space via $X|s> =|s+1>$ and $Z|s> =\omega^s |s>$, with $\omega=\exp(2i\pi/q)$. It has been found that the number of maximal mutually commuting sets within $\mathcal{P}_q$ is controlled by the Dedekind psi function $\psi(q)=q \prod_{p|q}(1+\frac{1}{p})$ (with $p$ a prime) \cite{Planat2011} and that there exists a specific inequality $\frac{\psi (q)}{q}>e^{\gamma}\log \log q$, involving the Euler constant $\gamma \sim 0.577$, that is only satisfied at specific low dimensions $q \in \mathcal {A}=\{2,3,4,5,6,8,10,12,18,30\}$. The set $\mathcal{A}$ is closely related to the set $\mathcal{A} \cup \{1,24\}$ of integers that are totally Goldbach, i.e. that consist of all primes $p2$) is equivalent to Riemann hypothesis. Introducing the Hardy-Littlewood function $R(q)=2 C_2 \prod_{p|n}\frac{p-1}{p-2}$ (with $C_2 \sim 0.660$ the twin prime constant), that is used for estimating the number $g(q) \sim R(q) \frac{q}{\ln^2 q}$ of Goldbach pairs, one shows that the new inequality $\frac{R(N_r)}{\log \log N_r} \gtrapprox e^{\gamma}$ is also equivalent to Riemann hypothesis. In this paper, these number theoretical properties are discusssed in the context of the qudit commutation structure.Comment: 11 page

Unified "micro"- and "macro-" evolution of eco-systems: Self-organization of a dynamic network

Very recently we have developed a dynamic network model for eco-systems that achieved ``unification'' of ``micro'' and ``macro''-evolution. We now propose an extension of our model so as to stabilize the eco-system and describe {\it speciation} in a more realistic manner.Comment: 7 pages with 3 figures; for Max Born Symposium, Poland, Sept. 200

Sur certaines relations entre les intégrales trajectorielles et l'opérateur de translation et son dual dans l'espace de Poisson canonique

We study the relationship between the translation operator, its dual and the pathwise integral on the Poisson space with weak conditions on the processes

Some asymptotic properties of duplication graphs

Duplication graphs are graphs that grow by duplication of existing vertices, and are important models of biological networks, including protein-protein interaction networks and gene regulatory networks. Three models of graph growth are studied: pure duplication growth, and two two-parameter models in which duplication forms one element of the growth dynamics. A power-law degree distribution is found to emerge in all three models. However, the parameter space of the latter two models is characterized by a range of parameter values for which duplication is the predominant mechanism of graph growth. For parameter values that lie in this ``duplication-dominated'' regime, it is shown that the degree distribution either approaches zero asymptotically, or approaches a non-zero power-law degree distribution very slowly. In either case, the approach to the true asymptotic degree distribution is characterized by a dependence of the scaling exponent on properties of the initial degree distribution. It is therefore conjectured that duplication-dominated, scale-free networks may contain identifiable remnants of their early structure. This feature is inherited from the idealized model of pure duplication growth, for which the exact finite-size degree distribution is found and its asymptotic properties studied.Comment: 19 pages, including 3 figure