9,319 research outputs found
Synchronization of interconnected networks: the role of connector nodes
In this Letter we identify the general rules that determine the
synchronization properties of interconnected networks. We study analytically,
numerically and experimentally how the degree of the nodes through which two
networks are connected influences the ability of the whole system to
synchronize. We show that connecting the high-degree (low-degree) nodes of each
network turns out to be the most (least) effective strategy to achieve
synchronization. We find the functional relation between synchronizability and
size for a given network-of-networks, and report the existence of the optimal
connector link weights for the different interconnection strategies. Finally,
we perform an electronic experiment with two coupled star networks and conclude
that the analytical results are indeed valid in the presence of noise and
parameter mismatches.Comment: Accepted for publication in Physical Review Letters. Main text: 5
pages, 4 figures. Supplemental material: 8 pages, 3 figure
Supersymmetric Musings on the Predictivity of Family Symmetries
We discuss the predictivity of family symmetries for the soft supersymmetry
breaking parameters in the framework of supergravity. We show that unknown
details of the messenger sector and the supersymmetry breaking hidden sector
enter into the soft parameters, making it difficult to obtain robust
predictions. We find that there are specific choices of messenger fields which
can improve the predictivity for the soft parameters.Comment: 20 pages, 5 figure
Does Culture Affect Divorce? Evidence From European Immigrants in the United States
This article explores the role of culture in determining divorce by examining country-of-origin differences in divorce rates of immigrants in the United States. Because childhood-arriving immigrants are all exposed to a common set of U.S. laws and institutions, we interpret relationships between their divorce tendencies and home-country divorce rates as evidence of the effect of culture. Our results are robust to controlling for several home-country variables, including average church attendance and gross domestic product (GDP). Moreover, specifications with country-of-origin fixed effects suggest that immigrants from countries with low divorce rates are especially less likely to be divorced if they reside among a large number of coethnics. Supplemental analyses indicate that divorce culture has a stronger impact on the divorce decisions of females than of males, pointing to a potentially gendered nature of divorce taboos
A Note on the Symmetry of Sequence Spaces
[EN] We give a self-contained treatment of symmetric Banach sequence spaces and some of their natural properties. We are particularly interested in the symmetry of the norm and the existence of symmetric linear functionals. Many of the presented results are known or commonly accepted, but are not found in the literature.D. Carando and M. Mazzitelli were supported by CONICET-PIP 11220130100329CO, ANPCyT PICT 2015-2299 and PICT 2018-4104.
P. Sevilla-Peris was supported by MICINN and FEDER project MTM2017-83262-C2-1-PCarando, D.; Mazzitelli, M.; Sevilla Peris, P. (2021). A Note on the Symmetry of Sequence Spaces. Mathematical Notes. 110(1-2):26-40. https://doi.org/10.1134/S000143462107003826401101-
Unión de péptidos a superficies de titanio para la mejora de la osteointegración
El presente estudio pretende mejorar el proceso de osteointegración del implante de titanio mediante la biofuncionalización de su superficie. Para ello se ha realizado una previa silanización de la superficie y una posterior unión covalente entre el silano y un péptido el cual posee la secuencia RGD. Se han estudiado diferentes aspectos como es la estabilidad tanto de conjunto titanio-silano como silano-péptido. Finalmente se ha realizado un ensayo de adhesión celular utilizando células osteoblásticas MG63 cuyas muestras de titanio han sido previamente biofuncionalizadas con el proceso estudiado.This study aims to improve the osseointegration process of the titanium implant through surface biofunctionalization. Samples were silanised on the surface and afterwards a peptide with the RGD sequence was covalently attached to the silane. Specific characteristics of the stability of the union titanium-silane as well as silane-peptide were studied. Finally cell adhesion studies to samples biofunctionalized with the technique studied in this work were made with MG63 osteoblastic cells.Peer Reviewe
Node Sampling using Random Centrifugal Walks
Sampling a network with a given probability distribution has been identified
as a useful operation. In this paper we propose distributed algorithms for
sampling networks, so that nodes are selected by a special node, called the
\emph{source}, with a given probability distribution. All these algorithms are
based on a new class of random walks, that we call Random Centrifugal Walks
(RCW). A RCW is a random walk that starts at the source and always moves away
from it.
Firstly, an algorithm to sample any connected network using RCW is proposed.
The algorithm assumes that each node has a weight, so that the sampling process
must select a node with a probability proportional to its weight. This
algorithm requires a preprocessing phase before the sampling of nodes. In
particular, a minimum diameter spanning tree (MDST) is created in the network,
and then nodes' weights are efficiently aggregated using the tree. The good
news are that the preprocessing is done only once, regardless of the number of
sources and the number of samples taken from the network. After that, every
sample is done with a RCW whose length is bounded by the network diameter.
Secondly, RCW algorithms that do not require preprocessing are proposed for
grids and networks with regular concentric connectivity, for the case when the
probability of selecting a node is a function of its distance to the source.
The key features of the RCW algorithms (unlike previous Markovian approaches)
are that (1) they do not need to warm-up (stabilize), (2) the sampling always
finishes in a number of hops bounded by the network diameter, and (3) it
selects a node with the exact probability distribution
Differential Regulation of PI3K Related Transcripts in Visceral Adipose Tissue from Obese Adolescent African-American Females
Please view abstract in the attached PDF file
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