Search results for "Theory"
showing 10 items of 24627 documents
11 and 15-month-old infants do not compensate immediately for energy variation, and no further adjustment occurs 12 or 24 hours later
2021
International audience; Previously, we demonstrated that, in the short term, infants undercompensated for the energy from a preload given 25 min before an ad libitum meal. However, although not consistent, there is evidence in young children that caloric adjustment may occur over longer periods. We investigated the extent to which further energy adjustment occurs up to 24 h after a single meal preceded by preloads of varying energy density (ED) in infants that are 11 and 15 months old. Short-term caloric adjustment was measured in 11- and 15-month-old infants through a preload paradigm meal in the laboratory. To assess their caloric adjustment over longer periods (12 and 24 h), we used 24 h…
Wavelength selection of rippling patterns in myxobacteria
2016
Rippling patterns of myxobacteria appear in starving colonies before they aggregate to form fruiting bodies. These periodic traveling cell density waves arise from the coordination of individual cell reversals, resulting from an internal clock regulating them, and from contact signaling during bacterial collisions. Here we revisit a mathematical model of rippling in myxobacteria due to Igoshin et al.\ [Proc. Natl. Acad. Sci. USA {\bf 98}, 14913 (2001) and Phys. Rev. E {\bf 70}, 041911 (2004)]. Bacteria in this model are phase oscillators with an extra internal phase through which they are coupled to a mean-field of oppositely moving bacteria. Previously, patterns for this model were obtaine…
Quantum field inspired model of decision making: Asymptotic stabilization of belief state via interaction with surrounding mental environment
2018
This paper is devoted to justification of quantum-like models of the process of decision making based on the theory of open quantum systems, i.e. decision making is considered as decoherence. This process is modeled as interaction of a decision maker, Alice, with a mental (information) environment ${\cal R}$ surrounding her. Such an interaction generates "dissipation of uncertainty" from Alice's belief-state $\rho(t)$ into ${\cal R}$ and asymptotic stabilization of $\rho(t)$ to a steady belief-state. The latter is treated as the decision state. Mathematically the problem under study is about finding constraints on ${\cal R}$ guaranteeing such stabilization. We found a partial solution of th…
Generalized Molecular Descriptors Derived From Event-Based Discrete Derivative.
2016
In the present study, a generalized approach for molecular structure characterization is introduced, based on the relation frequency matrix (F) representation of the molecular graph and the subsequent calculation of the corresponding discrete derivative (finite difference) over a pair of elements (atoms). In earlier publications (22- 24), an unique event, named connected subgraphs, (based on the Kier-Hall's subgraphs) was systematically employed for the computation of the matrix F. The present report is a generalization of this notion, in which eleven additional events are introduced, classified in three categories, namely, topological (terminal paths, vertex path incidence, quantum subgrap…
2019
Background: Network science provides powerful access to essential organizational principles of the brain. The aim of this study was to investigate longitudinal evolution of gray matter networks in early relapsing–remitting MS (RRMS) compared with healthy controls (HCs) and contrast network dynamics with conventional atrophy measurements. Methods: For our longitudinal study, we investigated structural cortical networks over 1 year derived from 3T MRI in 203 individuals (92 early RRMS patients with mean disease duration of 12.1 ± 14.5 months and 101 HCs). Brain networks were computed based on cortical thickness inter-regional correlations and fed into graph theoretical analysis. Network conne…
Statistical characterization of deviations from planned flight trajectories in air traffic management
2016
Understanding the relation between planned and realized flight trajectories and the determinants of flight deviations is of great importance in air traffic management. In this paper we perform an in depth investigation of the statistical properties of planned and realized air traffic on the German airspace during a 28 day periods, corresponding to an AIRAC cycle. We find that realized trajectories are on average shorter than planned ones and this effect is stronger during night-time than daytime. Flights are more frequently deviated close to the departure airport and at a relatively large angle to destination. Moreover, the probability of a deviation is higher in low traffic phases. All the…
Dissipation in suspension system augmented by piezoelectric stack: port-Hamiltonian approach
2020
Analysis of damping in semi-active and active suspension systems is prerequisite for an advanced control and, eventually, energy harvesting functions. This paper addresses the damping in suspension system augmented by the piezoelectric (PE) stack. The Hamiltonian system approach with port-power modeling of single subsystems is used for describing and studying the dissipative properties of piezoelectric stack element, integrated in series with a standard quarter-car suspension. The slightly improved, compared to the underlying passive suspension system, frequency response of the sprung mass acceleration is demonstrated. Moreover, the overall power flow in the system, caused by the disturbing…
A New Experiment for the Measurement of the g-Factors of 3He+ and 3He2+.
2018
We describe a new experiment that aims at a parts per billion measurement of the nuclear magnetic moment of 3He2+ and a 100 parts per trillion measurement of the Zeeman effect of the ground-state hyperfine splitting of 3He+. To enable ultrafast and efficient experiment cycles the experiment relies on new technologies such as sympathetic laser cooling of single 3He-ions coupled to a cloud of Doppler-cooled 9Be-ions in a Penning trap or a novel spin-state detection scheme.
Modulation of information processing by AMPA receptor auxiliary subunits
2020
AMPA-type glutamate receptors (AMPARs) are key molecules of neuronal communication in our brain. The discovery of AMPAR auxiliary subunits, such as proteins of the TARP, CKAMP and CNIH families, fundamentally changed our understanding of how AMPAR function is regulated. Auxiliary subunits control almost all aspects of AMPAR function in the brain. They influence AMPAR assembly, composition, structure, trafficking, subcellular localization and gating. This influence has important implications for synapse function. In the present review, we first discuss how auxiliary subunits affect the strength of synapses by modulating number and localization of AMPARs in synapses as well as their glutamate…
A Thermodynamic Model of Monovalent Cation Homeostasis in the Yeast Saccharomyces cerevisiae
2016
Cationic and heavy metal toxicity is involved in a substantial number of diseases in mammals and crop plants. Therefore, the understanding of tightly regulated transporter activities, as well as conceiving the interplay of regulatory mechanisms, is of substantial interest. A generalized thermodynamic description is developed for the complex interplay of the plasma membrane ion transporters, membrane potential and the consumption of energy for maintaining and restoring specific intracellular cation concentrations. This concept is applied to the homeostasis of cation concentrations in the yeast cells of S. cerevisiae. The thermodynamic approach allows to model passive ion fluxes driven by the…