5,631 research outputs found
NetEvo: A computational framework for the evolution of dynamical complex networks
NetEvo is a computational framework designed to help understand the evolution
of dynamical complex networks. It provides flexible tools for the simulation of
dynamical processes on networks and methods for the evolution of underlying
topological structures. The concept of a supervisor is used to bring together
both these aspects in a coherent way. It is the job of the supervisor to rewire
the network topology and alter model parameters such that a user specified
performance measure is minimised. This performance measure can make use of
current topological information and simulated dynamical output from the system.
Such an abstraction provides a suitable basis in which to study many
outstanding questions related to complex system design and evolution
A 22-Week-Old Fetus with Nager Syndrome and Congenital Diaphragmatic Hernia due to a Novel SF3B4 Mutation.
Nager syndrome, or acrofacial dysostosis type 1 (AFD1), is a rare multiple malformation syndrome characterized by hypoplasia of first and second branchial arches derivatives and appendicular anomalies with variable involvement of the radial/axial ray. In 2012, AFD1 has been associated with dominant mutations in SF3B4. We report a 22-week-old fetus with AFD1 associated with diaphragmatic hernia due to a previously unreported SF3B4 mutation (c.35-2A>G). Defective diaphragmatic development is a rare manifestation in AFD1 as it is described in only 2 previous cases, with molecular confirmation in 1 of them. Our molecular finding adds a novel pathogenic splicing variant to the SF3B4 mutational spectrum and contributes to defining its prenatal/fetal phenotype
Increasing Competency for Parents of Adolescents with Executive Functioning Deficits: Enhancing Occupational Performance with Mindfulness
Background: Executive functions are higher order cognitive processes occurring in the frontal lobe that influence cognitive, emotional, and behavioral functions. Adolescents with executive functioning deficits are at risk for difficulties in all domains of occupational functioning. Parents of these adolescents often live in a persistent state of stress that leads to highly reactive exchanges with their children. Studies have shown that a mindful approach to parenting can enhance a parent’s caregiving ability and self-awareness in the family unit.
Methods: A pretest/posttest study evaluated the effectiveness of a 6-week mindful parenting program. Four parents of adolescents with executive function deficits participated in six consecutive group sessions for 1.5 hr each, one time per week, to learn mindful strategies.
Results: Although most results were not found to be statistically significant, findings demonstrated promising trends for three of the parents. Statistically significant results indicated that one parent experienced improved communication with his or her adolescent, two had fewer concerns at school for their adolescent, three showed increased ability to problem-solve, one decreased his or her perfectionistic parenting skills, and one was more likely to be in the middle between the other parent and their adolescent.
Conclusions: Support for parents after program conclusion may be necessary to promote lasting change. Further research is needed with larger groups and longer periods to determine the effectiveness of mindfulness programs for parents with adolescents with executive functioning deficits
Maximum Entropy and Bayesian Data Analysis: Entropic Priors
The problem of assigning probability distributions which objectively reflect
the prior information available about experiments is one of the major stumbling
blocks in the use of Bayesian methods of data analysis. In this paper the
method of Maximum (relative) Entropy (ME) is used to translate the information
contained in the known form of the likelihood into a prior distribution for
Bayesian inference. The argument is inspired and guided by intuition gained
from the successful use of ME methods in statistical mechanics. For experiments
that cannot be repeated the resulting "entropic prior" is formally identical
with the Einstein fluctuation formula. For repeatable experiments, however, the
expected value of the entropy of the likelihood turns out to be relevant
information that must be included in the analysis. The important case of a
Gaussian likelihood is treated in detail.Comment: 23 pages, 2 figure
Determinant factors of bank customers' demand for liquidity
In contexts of economic instability investors show an increase in aversion to risk and prefer high liquidity and low-risk financial products. In this paper, we study the reasons behind bank customers holding wealth in the form of immediate liquidity. Using micro data on clients’ portfolios of a Portuguese bank, we ask whether there is a relationship between the bank’s capital ratio and the proportion of wealth that clients allocate to demand deposits, which is a relatively unexplored topic in the literature. Special attention is also paid to the impact of investors' financial knowledge by looking at professional group and age. Results indicate that when banks’ capital ratio decreases, savers put a larger fraction of their investment into demand deposits, especially savers with greater risk aversion and knowledge. Finally, we find evidence of an “age effect” and also that investors belonging to professional groups with more skills follow more sophisticated investment strategies.FC
Effective Dielectric Response of Metamaterials
We use a homogenization procedure for Maxwell's equations in order to obtain
in the local limit the frequency () dependent macroscopic dielectric
response of metamaterials made of natural constituents
with any geometrical shape repeated periodically with any structure. We
illustrate the formalism calculating for several
structures. For dielectric rectangular inclusions within a conducting material
we obtained a very anisotropic response which changes along one direction from
conductor-like at low to a resonant dielectric-like at large ,
attaining a very small reflectance at intermediate frequencies unrelated to
surface plasmon excitation and which can be tuned through geometrycal
tayloring. A similar behavior is obtained for other shapes close to the
percolation threshold.Comment: 16 pages 7 figures. Accepted in Phys. Rev. B (2009-06-08
An Experimental Histopathological Rating Scale of Sedimentation Stress in the Caribbean Coral Montastraea cavernosa
Colonies of Montastraea cavernosa were exposed to daily applications of approx. 200–225 mg cm– 2 sediments, during a four-week period, in order to investigate coral responses to increased sedimentation. Effects were assessed based on the histopathological condition of specimen tissues. Mild stress responses were noted as early as week one, including tissue swelling and polyp retraction, as well as changes in size and appearance of mucous secretory cells. As stress progressed, further inflammation of the mucous secretory cells was observed. Severe effects were observed in weeks 3 and 4, including atrophy of the outer epidermis, increased granularity and debris in gastrodermal cells of the middle and lower polyp region, as well as swelling and granularity of the calicoblastic epithelium. A semiquantitative rating scale was developed to score tissue condition based on the histopathological changes observed in control and treated corals. Although some signs of stress were also present in some control colonies, statistical analyses indicated significant differences in histopathological condition between control and treated corals. Our results confirm previous research that sublethal effects of sedimentation on corals are complex, involving both localized and systemic cell injury. Our results offer insight with regards to the diagnosis of healthy vs. unhealthy condition in reef corals, and provide a framework to survey for cellular reactions to environmental stress in coral reefs
Polarization forces in water deduced from single molecule data
Intermolecular polarization interactions in water are determined using a
minimal atomic multipole model constructed with distributed polarizabilities.
Hydrogen bonding and other properties of water-water interactions are
reproduced to fine detail by only three multipoles , , and
and two polarizabilities and , which
characterize a single water molecule and are deduced from single molecule data.Comment: 4 revtex pages, 3 embedded color PS figure
Molecular analysis of sarcomeric and non-sarcomeric genes in patients with hypertrophic cardiomyopathy.
Background: Hypertrophic cardiomyopathy (HCM) is a common genetic heart disorder characterized by
unexplained left ventricle hypertrophy associated with non-dilated ventricular chambers. Several genes
encoding heart sarcomeric proteins have been associated to HCM, but a small proportion of HCM patients
harbor alterations in other non-sarcomeric loci. The variable expression of HCM seems influenced by genetic
modifier factors and new sequencing technologies are redefining the understanding of genotype–phenotype
relationships, even if the interpretations of the numerous identified variants pose several challenges.
Methods and results: We investigated 62 sarcomeric and non-sarcomeric genes in 41 HCM cases and in
3 HCM-related disorders patients. We employed an integrated approach that combines multiple tools for
the prediction, annotation and visualization of functional variants. Genotype–phenotype correlations
were carried out for inspecting the involvement of each gene in age onset and clinical variability of HCM. The
80% of the non-syndromic patients showed at least one rare non-synonymous variant (nsSNV) and among
them, 58% carried alterations in sarcomeric loci, 14% in desmosomal and 7% in other non-sarcomeric ones
without any sarcomere change. Statistical analyses revealed an inverse correlation between the number of
nsSNVs and age at onset, and a relationship between the clinical variability and number and type of variants.
Conclusions: Our results extend the mutational spectrum of HCM and contribute in defining the molecular
pathogenesis and inheritance pattern(s) of this condition. Besides, we delineate a specific procedure for the
identification of the most likely pathogenetic variants for a next generation sequencing approach embodied in
a clinical context
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