Social interactions in Hypsiboas albomarginatus (Anura : Hylidae) and the significance of acoustic and visual signals

Social behavior of Hypsiboas albomarginatus was studied in the Atlantic rain forest, Municipality of Ubatuba, in the north coast of the State of São Paulo, southeastern Brazil. Vocalizations of H. albomarginatus are described, including contexts in which they were emitted and temporal and spectral parameters differentiating advertisement from aggressive calls. Dominant call frequency was inversely correlated with male length and body mass but not with environmental temperature. Number of pulses per note was not correlated with any variable, and advertisement call amplitude was influenced by temperature and time. During chorus aggregation, males interacted acoustically by emitting advertisement calls in antiphony, or by emitting aggressive calls. Some disputes among males culminated in physical combat; males performed kicks and slaps on rivals' heads, in an apparent attempt to dislodge rivals from perches. Visual signals were also displayed during conflicts between males, contributing to an escalation of aggressive behavior. Visual signals were not recorded during courtship between males and females but may help in the accurate localization of the signaling male during aggressive interactions.

L-R asymmetries and signals for new bosons

Several left-right parity violating asymmetries in lepton-lepton scattering in fixed target and collider experiments are considered as signals for doubly charged vector bosons (bileptons).

Radion and Higgs signals in peripheral heavy ion collisions at the LHC

We investigate the sensitivity of the heavy ion mode of the LHC to Higgs boson and Radion production via photon-photon fusion through the analysis of the processes gammagamma --> gammagamma, gammagamma --> b (b) over bar, and gammagamma --> gg in peripheral heavy ion collisions. We suggest cuts to improve the Higgs and Radion signal over standard model background ratio and determine the capability of LHC to detect these particles production. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Remarks on Bessel beams, signals and superluminality

We address the question about the velocity of signals carried by Bessel beams wave packets propagating in vacuum and having well defined wavefronts in time. We find that this problem in analogous to that of propagation of usual plane wave packets within dispersive media and conclude that the signal velocity cannot be superluminal. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Signals for new spin-1 resonances in electroweak gauge boson pair production at the LHC

The mechanism of electroweak symmetry breaking ( EWSB) will be directly scrutinized soon at the CERN Large Hadron Collider. We analyze the LHC potential to look for new vector bosons associated with the EWSB sector, presenting a possible model independent approach to search for these new spin-1 resonances. We show that the analyses of the processes pp -> l(+)l(1-)E(T), l +/- jjE(T), l(1 +/-)l(+)l(-)E(T), l(+/-)jjE(T), and l(+)l(-) jj (with l, l' = e or mu and j = jet) have a large reach at the LHC and can lead to the discovery or exclusion of many EWSB scenarios such as Higgsless models.

Can we observe the radion and Higgs signals in peripheral heavy ion collisions?

We investigate the sensitivity of the heavy ion mode of the LHC to Higgs boson and Radion production via photon-photon fusion through the analysis of the processes gg -> gg, gg ->, and gg ® ggin peripheral heavy ion collisions. We suggest cuts to improve the Higgs and Radion signal over standard model background ratio and determine the capability of LHC to detect these particles production.

Analysis of transient otoacoustic emissions and brainstem evoked auditory potentials in neonates with hyperbilirubinemia

A hiperbilirrubinemia é tóxica às vias auditivas e ao sistema nervoso central, deixando sequelas como surdez e encefalopatia. OBJETIVOS: avaliar a audição de neonatos portadores de hiperbilirrubinemia, utilizando-se a pesquisa das emissões otoacústicas evocadas transientes (EOAET) e dos potenciais evocados auditivos do tronco encefálico (PEATE). Estudo prospectivo. CASUÍSTICA E MÉTODOS: Constituíram-se dois grupos: GI (n-25), neonatos com hiperbilirrubinemia; GII (n-22), neonatos sem hiperbilirrubinemia e sem fatores de risco para surdez. Todos os neonatos tinham até 60 dias de vida e foram submetidos à EOAET e ao PEATE. RESULTADOS: 12 neonatos de GI e 10 de GII eram meninas e 13 de GI e 12 de GII eram meninos. As EOAET estavam presentes em todas as crianças, porém com amplitudes menores em GI, especialmente nas frequências de 2 e 3KHz (p < 0,05). No PEATE, observou-se discreto prolongamento de PV e de LI-V em GI. As alterações observadas nesses testes não se correlacionaram aos níveis séricos da bilirrubinemia. CONCLUSÕES: em neonatos portadores de hiperbilirrubinemia, menores amplitudes das EOAET e discreto prolongamento de PV e de LI-V foram constatados indicando comprometimento coclear e retrococlear das vias auditivas, salientando-se a importância da utilização e da interpretação minuciosa de ambos os testes nessas avaliações.

Auditory processing in children and adolescents in situations of risk and vulnerability

CONTEXTO E OBJETIVO: Crianças e adolescentes que vivem em situação de vulnerabilidade social apresentam uma série de problemas de saúde. Apesar disso, ainda é controversa a afirmação sobre a existência de alterações cognitivas e/ou sensoriais. O objetivo deste estudo foi investigar aspectos relacionados ao processamento auditivo, através da aplicação de testes de potencial evocado auditivo de tronco encefálico (PEATE) e avaliação comportamental do processamento auditivo em crianças em situação de rua, comparando a um grupo controle. TIPO DE ESTUDO E LOCAL: Estudo transversal no Laboratório de Processamento Auditivo, Faculdade de Medicina da Universidade de São Paulo. MÉTODOS: Os testes de processamento auditivo foram aplicados em um grupo de 27 indivíduos, subdivididos em grupos de 11 crianças (7 a 10 anos) e 16 adolescentes (11 a 16 anos) de ambos os sexos, em situação de vulnerabilidade social, e comparado a um grupo controle, formado por 21 crianças, subdivididas em grupos de 10 crianças e 11 adolescentes, pareados por idade, sem queixas. Também se aplicou os PEATE para investigação da integridade da via auditiva. RESULTADOS: Para ambas as faixas etárias, foram encontradas diferenças significantes entre grupos estudo e controle para a maioria dos testes aplicados, sendo que o grupo estudo apresentou desempenho estatisticamente pior do que o controle para todos os testes, exceto para o teste pediatric speech intelligibility. Apenas uma criança apresentou resultado alterado para os PEATE. CONCLUSÕES: Os resultados demonstraram pior desempenho do grupo estudo (crianças e adolescentes) para os testes comportamentais de processamento auditivo, apesar de estes apresentarem integridade da via auditiva em nível de tronco encefálico, demonstrada pela normalidade nos resultados do PEATE.

TEMPORAL COUPLING BETWEEN EXTERNAL AUDITORY INFORMATION AND THE PHASES OF WALKING

The purpose of this study was to investigate the effects of an imposed external auditory constraint upon the temporal organization of walking. Ten subjects were videotaped walking normally (N) and with instructions to couple naturally, at mid-swing, or at toe-off to a metronome beat. Based upon an analysis of variance and post hoc Scheffe tests most temporal variables were not significantly different among conditions. The duration of swing phase was significantly different between natural coupling and toe-off. The deviation from the metronome beat was significantly different between the natural coupling and both mid-swing and toe-off. Subjects generally were not successful in achieving coupling during the latter conditions. Thigh and shank phase portraits were used to describe the system's organization to the external constraint.

Economic design of two-stage (X)over-bar charts: the Markov chain approach

When the (X) over bar chart is in use, samples are regularly taken from the process, and their means are plotted on the chart. In some cases, it is too expensive to obtain the X values, but not the values of a correlated variable Y. This paper presents a model for the economic design of a two-stage control chart, that is. a control chart based on both performance (X) and surrogate (Y) variables. The process is monitored by the surrogate variable until it signals an out-of-control behavior, and then a switch is made to the (X) over bar chart. The (X) over bar chart is built with central, warning. and action regions. If an X sample mean falls in the central region, the process surveillance returns to the (Y) over bar chart. Otherwise. The process remains under the (X) over bar chart's surveillance until an (X) over bar sample mean falls outside the control limits. The search for an assignable cause is undertaken when the performance variable signals an out-of-control behavior. In this way, the two variables, are used in an alternating fashion. The assumption of an exponential distribution to describe the length of time the process remains in control allows the application of the Markov chain approach for developing the cost function. A study is performed to examine the economic advantages of using performance and surrogate variables. (C) 2003 Elsevier B.V. All rights reserved.

Auditory processing disorder in patients with language-learning impairment and correlation with malformation of cortical development

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Auditory processing disorder in perisylvian syndrome

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)