Secondary stress in Brazilian Portuguese: the interplay between production and perception studies

This paper reports experiments on speech production showing that secondary stress in Brazilian Portuguese (BP) can be best described as phrase-initial prominence cued by greater duration and pitch accent excursion in initial position. It also reports a perception experiment in which clicks were associated to consecutive V-to-V positions in stress groups. Mean click detection RTs are gradient, but show no influence of initial lengthening. RTs near the phrasally stressed position are shorter and almost 60% of RT variance can be accounted for by produced timing patterns

Surface magnetization in non-doped ZnO nanostructures

We have investigated the magnetic properties of non-doped ZnO nanostructures by using {\it ab initio} total energy calculations. Contrary to many proposals that ferromagnetism in non-doped semiconductors should be induced by intrinsic point defects, we show that ferromagnetism in nanostructured materials should be mediated by extended defects such as surfaces and grain boundaries. This kind of defects create delocalized, spin polarized states that should be able to warrant long-range magnetic interactions.Comment: 8 pages, 3 figure

VCube-PS: A Causal Broadcast Topic-based Publish/Subscribe System

In this work we present VCube-PS, a topic-based Publish/Subscribe system built on the top of a virtual hypercube-like topology. Membership information and published messages are broadcast to subscribers (members) of a topic group over dynamically built spanning trees rooted at the publisher. For a given topic, the delivery of published messages respects the causal order. VCube-PS was implemented on the PeerSim simulator, and experiments are reported including a comparison with the traditional Publish/Subscribe approach that employs a single rooted static spanning-tree for message distribution. Results confirm the efficiency of VCube-PS in terms of scalability, latency, number and size of messages.Comment: Improved text and performance evaluation. Added proof for the algorithms (Section 3.4

A Bag-of-Tasks Scheduler Tolerant to Temporal Failures in Clouds

Cloud platforms have emerged as a prominent environment to execute high performance computing (HPC) applications providing on-demand resources as well as scalability. They usually offer different classes of Virtual Machines (VMs) which ensure different guarantees in terms of availability and volatility, provisioning the same resource through multiple pricing models. For instance, in Amazon EC2 cloud, the user pays per hour for on-demand VMs while spot VMs are unused instances available for lower price. Despite the monetary advantages, a spot VM can be terminated, stopped, or hibernated by EC2 at any moment. Using both hibernation-prone spot VMs (for cost sake) and on-demand VMs, we propose in this paper a static scheduling for HPC applications which are composed by independent tasks (bag-of-task) with deadline constraints. However, if a spot VM hibernates and it does not resume within a time which guarantees the application's deadline, a temporal failure takes place. Our scheduling, thus, aims at minimizing monetary costs of bag-of-tasks applications in EC2 cloud, respecting its deadline and avoiding temporal failures. To this end, our algorithm statically creates two scheduling maps: (i) the first one contains, for each task, its starting time and on which VM (i.e., an available spot or on-demand VM with the current lowest price) the task should execute; (ii) the second one contains, for each task allocated on a VM spot in the first map, its starting time and on which on-demand VM it should be executed to meet the application deadline in order to avoid temporal failures. The latter will be used whenever the hibernation period of a spot VM exceeds a time limit. Performance results from simulation with task execution traces, configuration of Amazon EC2 VM classes, and VMs market history confirms the effectiveness of our scheduling and that it tolerates temporal failures

Specificity and performance evaluation of a novel RNA-FISH probe for the identification of Rhodotorula sp.

To distinguish Rhodotorula sp., from other microorganisms that produce the same type of alterations on CH materials, proper identification methods must be applied. RNA-fluorescence and in situ hybridization (RNA-FISH) has the potential to specifically identify the target microorganism of interest in complex microbial communities (it is based on hybridization of fluorescently-labeled oligonucleotide probes targeting to specific regions of the ribosomal RNA). Thus, the aim of this study was to design a novel genus specific RNAFISH probe against Rhodotorula sp., and to evaluate its specificity and performance both in silico and experimentally. This will contribute for facilitating Rhodotorula sp., identification in degraded CH materials by RNA-FISH.This work was co-financed by FCT through PTDC/BBB-IMG/0046/2014 project and SFRH/BPD/100754/2014 grant and by ALT20-03-0246-FEDER-000004-ALENTEJO 2020 project

Sexto ciclo de seleção recorrente fenotípica visando resistência à mancha-angular no feijoeiro.

Neste trabalho são apresentados os resultados obtidos na avaliação de progênies do sexto ciclo de seleção do referido programa

Interplay between dipole and quadrupole modes of field influence in liquid-crystalline suspensions of ferromagnetic particles

In the framework of continuum theory we study orientational transitions induced by electric and magnetic fields in ferronematics, i.e., in liquid-crystalline suspensions of ferromagnetic particles. We have shown that in a certain electric field range the magnetic field can induce a sequence of re-entrant orientational transitions in ferronematic layer: nonuniform phase --- uniform phase --- nonuniform phase. This phenomenon is caused by the interplay between the dipole (ferromagnetic) and quadrupole (dielectric and diamagnetic) mechanisms of the field influence on a ferronematic structure. We have found that these re-entrant Freedericksz transitions exhibit tricritical behavior, i.e., they can be of the first or the second order. The character of the transitions depends on a degree of redistribution of magnetic admixture in the sample exposed to uniform magnetic field (magnetic segregation). We demonstrate how electric and magnetic fields can change the order of orientational transitions in ferronematics. We show that electric Freedericksz transitions in ferronematics subjected to magnetic field have no re-entrant nature. Tricritical segregation parameters for the transitions induced by electric or magnetic fields are obtained analytically. We demonstrate the re-entrant behavior of ferronematic by numerical simulations of the magnetization and optical phase lag.Comment: 12 pages, 9 figures, to be published in Soft Matte