1,324 research outputs found
A unified design space of synthetic stripe-forming networks
Synthetic biology is a promising tool to study the function and properties of gene regulatory networks. Gene circuits with predefined behaviours have been successfully built and modelled, but largely on a case-by-case basis. Here we go beyond individual networks and explore both computationally and synthetically the design space of possible dynamical mechanisms for 3-node stripe-forming networks. First, we computationally test every possible 3-node network for stripe formation in a morphogen gradient. We discover four different dynamical mechanisms to form a stripe and identify the minimal network of each group. Next, with the help of newly established engineering criteria we build these four networks synthetically and show that they indeed operate with four fundamentally distinct mechanisms. Finally, this close match between theory and experiment allows us to infer and subsequently build a 2-node network that represents the archetype of the explored design space
Inferring broken detailed balance in the absence of observable currents
Identifying dissipation is essential for understanding the physical
mechanisms underlying nonequilibrium processes. {In living systems, for
example, the dissipation is directly related to the hydrolysis of fuel
molecules such as adenosine triphosphate (ATP)}. Nevertheless, detecting broken
time-reversal symmetry, which is the hallmark of dissipative processes, remains
a challenge in the absence of observable directed motion, flows, or fluxes.
Furthermore, quantifying the entropy production in a complex system requires
detailed information about its dynamics and internal degrees of freedom. Here
we introduce a novel approach to detect time irreversibility and estimate the
entropy production from time-series measurements, even in the absence of
observable currents. We apply our technique to two different physical systems,
namely, a partially hidden network and a molecular motor. Our method does not
require complete information about the system dynamics and thus provides a new
tool for studying nonequilibrium phenomena.Comment: 14 pages, 6 figure
Depletion-Isolation Effect in Vertical MOSFETs During the Transition From Partial to Fully Depleted Operation
A simulation study is made of floating-body effects (FBEs) in vertical MOSFETs due to depletion isolation as the pillar thickness is reduced from 200 to 10 nm. For pillar thicknesses between 200â60 nm, the output characteristics with and without impact ionization are identical at a low drain bias and then diverge at a high drain bias. The critical drain bias Vdc for which the increased drainâcurrent is observed is found to decrease with a reduction in pillar thickness. This is explained by the onset of FBEs at progressively lower values of the drain bias due to the merging of the drain depletion regions at the bottom of the pillar (depletion isolation). For pillar thicknesses between 60â10 nm, the output characteristics show the opposite behavior, namely, the critical drain bias increases with a reduction in pillar thickness. This is explained by a reduction in the severity of the FBEs due to the drain debiasing effect caused by the elevated body potential. Both depletion isolation and gateâgate coupling contribute to the drainâcurrent for pillar thicknesses between 100â40 nm
Verification in Relevant Environment of a Physics-Based Synthetic Sensor for Flow Angle Estimation
In the area of synthetic sensors for flow angle estimation, the present work aims to describe the verification in a relevant environment of a physics-based approach using a dedicated technological demonstrator. The flow angle synthetic solution is based on a model-free, or physics-based, scheme and, therefore, it is applicable to any flying body. The demonstrator also encompasses physical sensors that provide all the necessary inputs to the synthetic sensors to estimate the angle-of-attack and the angle-of-sideslip. The uncertainty budgets of the physical sensors are evaluated to corrupt the flight simulator data with the aim of reproducing a realistic scenario to verify the synthetic sensors. The proposed approach for the flow angle estimation is suitable for modern and future aircraft, such as drones and urban mobility air vehicles. The results presented in this work show that the proposed approach can be effective in relevant scenarios even though some limitations can arise
Telling faults from cyber-attacks in a multi-modal logistic system with complex network analysis
We investigate the properties of systems of systems in a cybersecurity context by using complex network methodologies. We are interested in resilience and attribution. The first relates to the system's behavior in case of faults/attacks, namely to its capacity to recover full or partial functionality after a fault/attack. The second corresponds to the capability to tell faults from attacks, namely to trace the cause of an observed malfunction back to its originating cause(s). We present experiments to witness the effectiveness of our methodology considering a discrete event simulation of a multimodal logistic network featuring 40 nodes distributed across Italy and daily traffic roughly corresponding to the number of containers shipped through in Italian ports yearly averaged daily
Sostenible - No sostenible
Esta breve contribuciĂłn, dentro del bloque temĂĄtico âIniciativas-motor de cambioâ,
contiene una idea principal: la insostenibilidad intrĂnseca del desarrollo humano. Afortunadamente, esta âno-sostenibilidadâ es sĂłlo un tema de nomenclatura que se refiere al significado literal del tĂ©rmino; no es un problema de fondo que cuestione la
necesidad de desarrollar polĂticas y estrategias orientadas al Desarrollo Humano
âSostenibleâ (DHS).Peer Reviewe
Aldo Bernardini, Cinema muto italiano. Protagonisti | Itinerari nel cinema tra critica e storia
PrĂ©sentĂ© avec succĂšs aux derniĂšres « Giornate del Cinema Muto » de Pordenone (octobre 2018), lâouvrage dâAldo Bernardini sâimpose dâemblĂ©e comme un incontournable instrument de connaissance : prĂšs de 400 notices pour suivre la carriĂšre des « protagonistes » du cinĂ©ma muet italien. Dans sa prĂ©face, Pierre Sorlin Ă©crit « Le dictionnaire dâAldo Bernardini est la synthĂšse dâune longue investigation et de ses qualitĂ©s de chercheur : lâextraordinaire prĂ©cision, la maniĂšre brillante dâindiquer lâess..
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