4,607 research outputs found
Computing coset leaders and leader codewords of binary codes
In this paper we use the Gr\"obner representation of a binary linear code
to give efficient algorithms for computing the whole set of coset
leaders, denoted by and the set of leader codewords,
denoted by . The first algorithm could be adapted to
provide not only the Newton and the covering radius of but also to
determine the coset leader weight distribution. Moreover, providing the set of
leader codewords we have a test-set for decoding by a gradient-like decoding
algorithm. Another contribution of this article is the relation stablished
between zero neighbours and leader codewords
Two loops calculation in chiral perturbation theory and the unitarization program of current algebra
In this paper we compare two loop Chiral Perturbation Theory (ChPT)
calculation of pion-pion scattering with the unitarity second order correction
to the current algebra soft-pion theorem. It is shown that both methods lead to
the same analytic structure for the scattering amplitude.Comment: 13 pages, Revtex 3.0, no figures, submitted to Phys. Lett.
Handball coaches' perceptions about the value of working competences according to their coaching background
The purpose of this study was to analyze the value attributed to given working competences, by Portuguese handball coaches according to their coaching background, certification level, coaching experience, and level of education. A sample of 207 handball coaches responded to a questionnaire which included demographic characteristics and a scale focused on perceptions of the level of importance attributed to working competences. Data analysis included an exploratory factorial analysis applying Maximum Likelihood Factoring (MLF) and Oblimin rotation. These factors were submitted to a One-way ANOVA and Tukey's post hoc multiple comparisons to analyse coaches' perceptions according to their coaching background. A six factor solution was found where three major domains of competences were highlighted; the first one related to training and competition (e.g. planning and conducting the training, team administration in competition, annual and multi-annual planning, and coaching methodology); the second one related to social and cultural issues and management (e.g. implementation of youth sport development projects, team leadership and coach education) and the third one related to the cognitive background (meta-cognitive competences). The importance ascribed to some working competences was influenced by their coaching experience and certification level. Highly experienced and qualified coaches perceived competences of everyday practice, social, cultural and management issues related to training and competition as more important than the other coaches. This study suggests the need to consider some working competences, until now not explicitly present in the Portuguese coaching education curriculum which could enable coaches to choose the best way to practice/work in a manner that will foster and support their professional development. Key pointsThree major domains of competences were highlighted by Portuguese handball coaches. The first one related to training and competition, the second one related to social and cultural issues and management and the third one related to the cognitive background.The importance ascribed by Portuguese handball coaches to some working competences was influenced by their coaching experience and certification level, as high experienced coaches and coaches with higher certification levels perceived competences related to training and competition of the everyday practice and social, cultural issues and management as more important.The value attributed by Portuguese handball coaches to working competences did not vary according to the coaches' academic education level.Portuguese handball coaches valued the meta-cognitive competences, the competences to implement sport development project and related to annual and multi-annual planning independently of their coaching background
Estudos preliminares da floração e frutificação de jaborandi (Pilocarpus microphyllus Staff.) no banco de germoplasma da Embrapa Amazônia Oriental - CPATU - Belém-PA.
Phenomenology Tools on Cloud Infrastructures using OpenStack
We present a new environment for computations in particle physics
phenomenology employing recent developments in cloud computing. On this
environment users can create and manage "virtual" machines on which the
phenomenology codes/tools can be deployed easily in an automated way. We
analyze the performance of this environment based on "virtual" machines versus
the utilization of "real" physical hardware. In this way we provide a
qualitative result for the influence of the host operating system on the
performance of a representative set of applications for phenomenology
calculations.Comment: 25 pages, 12 figures; information on memory usage included, as well
as minor modifications. Version to appear in EPJ
Alterations in brain connectivity due to plasticity and synaptic delay
Brain plasticity refers to brain's ability to change neuronal connections, as
a result of environmental stimuli, new experiences, or damage. In this work, we
study the effects of the synaptic delay on both the coupling strengths and
synchronisation in a neuronal network with synaptic plasticity. We build a
network of Hodgkin-Huxley neurons, where the plasticity is given by the Hebbian
rules. We verify that without time delay the excitatory synapses became
stronger from the high frequency to low frequency neurons and the inhibitory
synapses increases in the opposite way, when the delay is increased the network
presents a non-trivial topology. Regarding the synchronisation, only for small
values of the synaptic delay this phenomenon is observed
Primary Antiphospholipid Syndrome: Pregnancy Outcome in a Portuguese Population
Introduction:Women with antiphospholipid syndrome(APS) may suffer from recurrent miscarriage, fetal death, fetal growth restriction (FGR), pre-eclampsia, placental abruption, premature delivery and thrombosis. Treatment with aspirin and
low molecular weight heparin (LMWH) combined
with close maternal-fetal surveillance can change these outcomes.
Objective: To assess maternal and perinatal outcome in a cohort of Portuguese women with primary APS.
Patients and Methods: A retrospective analysis of 51 women with primary APS followed in our institution (January 1994 to December 2007). Forty one(80.4%) had past pregnancy morbidity and 35.3%(n=18) suffered previous thrombotic events. In their past they had a total of 116 pregnancies of which
only 13.79 % resulted in live births. Forty four patients had positive anticardiolipin antibodies and 33 lupus anticoagulant. All women received treatment with low dose aspirin and LMWH.
Results: There were a total of 67 gestations (66 single and one multiple). The live birth rate was 85.1%(57/67) with 10 pregnancy failures: seven in the first and second trimesters, one late fetal death and two
medical terminations of pregnancy (one APS related).
Mean (± SD) birth weight was 2837 ± 812 g
and mean gestational age 37 ± 3.3 weeks. There were nine cases of FGR and 13 hypertensive complications(4 HELLP syndromes). 54.4% of the patients
delivered by caesarean section.
Conclusions: In our cohort, early treatment with aspirin and LMWH combined with close maternal-fetal surveillance was associated with a very high chance of a live newborn
Bloqueio Aurículo-Ventricular Completo Congénito. Caso Clínico e Revisão da Literatura
Introduction: Congenital complete atrioventricular block (AVB) without cardiac malformation is a rare and potentially fatal condition. In most cases it is associated with maternal systemic lupus erythematosus through transplacental passage of antibodies anti-SSA/Ro and/or anti-SSB/La. Antenatal fluorinated-steroids have been successful in reversing first and second degree congenital AVB but inconsistent in third degree block.
Case Report:The authors report a case of fetal bradycardia diagnosed at 24 weeks of gestation. The fetal echocardiogram revealed a second/third degree AVB without structural heart disease. Maternal anti-SSA/Ro antibodies were detected. There was no blockage improvement with maternal oral fluorinated-steroids. An elective cesarean section was performed at term with the delivery of a healthy girl that required an epicardical pacemaker on the 8th day of life.
Conclusion: In this case, treatment with maternal fluorinated corticosteroids was not effective in preventing progression of the heart block
Using quantum state protection via dissipation in a quantum-dot molecule to solve the Deutsch problem
The wide set of control parameters and reduced size scale make semiconductor
quantum dots attractive candidates to implement solid-state quantum
computation. Considering an asymmetric double quantum dot coupled by tunneling,
we combine the action of a laser field and the spontaneous emission of the
excitonic state to protect an arbitrary superposition state of the indirect
exciton and ground state. As a by-product we show how to use the protected
state to solve the Deutsch problem.Comment: 8 pages, 1 figure, 2 table
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