4,413 research outputs found
Quantitative comparison of dynamic flux distribution of magnetic couplers for roadway electric vehicle wireless charging system
published_or_final_versio
Parameterized Directed -Chinese Postman Problem and Arc-Disjoint Cycles Problem on Euler Digraphs
In the Directed -Chinese Postman Problem (-DCPP), we are given a
connected weighted digraph and asked to find non-empty closed directed
walks covering all arcs of such that the total weight of the walks is
minimum. Gutin, Muciaccia and Yeo (Theor. Comput. Sci. 513 (2013) 124--128)
asked for the parameterized complexity of -DCPP when is the parameter.
We prove that the -DCPP is fixed-parameter tractable.
We also consider a related problem of finding arc-disjoint directed
cycles in an Euler digraph, parameterized by . Slivkins (ESA 2003) showed
that this problem is W[1]-hard for general digraphs. Generalizing another
result by Slivkins, we prove that the problem is fixed-parameter tractable for
Euler digraphs. The corresponding problem on vertex-disjoint cycles in Euler
digraphs remains W[1]-hard even for Euler digraphs
Comparison of labour induction with misoprostol and dinoprostone and characterization of uterine response based on electrohysterogram
[EN] Objective: The objective of this study is to compare the uterine activity response between women administered dinoprostone (prostaglandin E2) and misoprostol (prostaglandin E1) for induction of labour (IOL) by analysing not only the traditional obstetric data but also the parameters extracted from uterine electrohysterogram (EHG).
Methods: Two cohorts were defined: misoprostol (25-mg vaginal tablets; 251 women) and dinoprostone cohort (10 mg vaginal inserts; 249 women). All the mothers were induced by a medical indication of a Bishop Score < Âż 6.
Results: The misoprostol cohort was associated with a shorter time to achieve active labour (p Âż .017) and vaginal delivery (p Âż .009) and with a higher percentage of vaginal delivery in less than 24 h in mothers with a very unfavourable cervix score (risk ratio (RR): 1.41, IC95% 1.17Âż1.69, p Âż .002). Successful inductions with misoprostol showed EHG parameter values significantly higher than basal state for amplitude and pseudo Montevideo units (PMU) 60Âż after drug administration, while spectral parameters significantly increased after 150Âż. This response was not observed in failed inductions. In the successful dinoprostone group, the duration and number of contractions increased significantly after 120Âż, PMU did so after 180Âż, and no significant differences were found for spectral parameters, possibly due to the slower pharmacokinetics of this drug.
Conclusion: Successful inductions of labour by misoprostol are associated with earlier effective contractions than in labours induced by dinoprostone.This work was partially supported by the Spanish Ministry of Economy and Competitiveness and the European Regional Development Fund under grant [DPI2015-68397-R] and by the company Bial SA.Benalcazar-Parra, C.; Monfort-Orti, R.; Ye Lin, Y.; Prats-Boluda, G.; Alberola Rubio, J.; Perales MarĂn, AJ.; Garcia-Casado, J. (2019). Comparison of labour induction with misoprostol and dinoprostone and characterization of uterine response based on electrohysterogram. The Journal of Maternal-Fetal & Neonatal Medicine. 32(10):1586-1594. https://doi.org/10.1080/14767058.2017.1410791S15861594321
Reducing the contents of free phenol and formaldehyde in phenolic foam
The problem of overly high contents of remnant monomers (free phenol and free formaldehyde) in phenolic foam was studied. Free phenol was characterized by iodimetry, and free formaldehyde was characterized by a hydroxylamine hydrochloride method. The effect of the phenol /formaldehyde molar ratios and the reaction temperature on the contents of the remnant monomers was examined. The effect of adding urea on the content of free formaldehyde was investigated. The effect of the foaming process on the contents of the remnant monomers was examined in detail. Phenolic foams in which the content of free phenol was 0.09% and the content of free formaldehyde was less than 0.1% were successfully prepared. A prepolymer of polyurethane, which toughened the phenolic foam, lowered the contents of free phenol and free formaldehyde. (C) 2003 Wiley Periodicals, Inc
Constructing Dirac linear fermions in terms of non-linear Heisenberg spinors
We show that the massive (or massless) neutrinos can be described as special
states of Heisenberg nonlinear spinors. As a by-product of this decomposition a
particularly attractive consequence appears: the possibility of relating the
existence of only three species of mass-less neutrinos to such internal
non-linear structure. At the same time it allows the possibility that neutrino
oscillation can occurs even for massless neutrinos
Homochirality and the need of energy
The mechanisms for explaining how a stable asymmetric chemical system can be
formed from a symmetric chemical system, in the absence of any asymmetric
influence other than statistical fluctuations, have been developed during the
last decades, focusing on the non-linear kinetic aspects. Besides the absolute
necessity of self-amplification processes, the importance of energetic aspects
is often underestimated. Going down to the most fundamental aspects, the
distinction between a single object -- that can be intrinsically asymmetric --
and a collection of objects -- whose racemic state is the more stable one --
must be emphasized. A system of strongly interacting objects can be described
as one single object retaining its individuality and a single asymmetry; weakly
or non-interacting objects keep their own individuality, and are prone to
racemize towards the equilibrium state. In the presence of energy fluxes,
systems can be maintained in an asymmetric non-equilibrium steady-state. Such
dynamical systems can retain their asymmetry for times longer than their
racemization time.Comment: 8 pages, 7 figures, submitted to Origins of Life and Evolution of
Biosphere
Timescales of Massive Human Entrainment
The past two decades have seen an upsurge of interest in the collective
behaviors of complex systems composed of many agents entrained to each other
and to external events. In this paper, we extend concepts of entrainment to the
dynamics of human collective attention. We conducted a detailed investigation
of the unfolding of human entrainment - as expressed by the content and
patterns of hundreds of thousands of messages on Twitter - during the 2012 US
presidential debates. By time locking these data sources, we quantify the
impact of the unfolding debate on human attention. We show that collective
social behavior covaries second-by-second to the interactional dynamics of the
debates: A candidate speaking induces rapid increases in mentions of his name
on social media and decreases in mentions of the other candidate. Moreover,
interruptions by an interlocutor increase the attention received. We also
highlight a distinct time scale for the impact of salient moments in the
debate: Mentions in social media start within 5-10 seconds after the moment;
peak at approximately one minute; and slowly decay in a consistent fashion
across well-known events during the debates. Finally, we show that public
attention after an initial burst slowly decays through the course of the
debates. Thus we demonstrate that large-scale human entrainment may hold across
a number of distinct scales, in an exquisitely time-locked fashion. The methods
and results pave the way for careful study of the dynamics and mechanisms of
large-scale human entrainment.Comment: 20 pages, 7 figures, 6 tables, 4 supplementary figures. 2nd version
revised according to peer reviewers' comments: more detailed explanation of
the methods, and grounding of the hypothese
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