Theta-associated high-frequency oscillations (110–160 Hz) in the hippocampus and neocortex

TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. . Theta-associated high-frequency oscillations (110-160 Hz) in the hippocampus and neocortex. Progress in Neurobiology , v. 100, p. 1-14, 2013.

Selective Coupling between Theta Phase and Neocortical Fast Gamma Oscillations during REM-Sleep in Mice

TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. . Theta-associated high-frequency oscillations (110-160 Hz) in the hippocampus and neocortex. Progress in Neurobiology , v. 100, p. 1-14, 2013.

Determining day length and temperature regulation of flowering: a molecular and modelling approach

Thesis (Ph.D.)--University of Washington, 2016-08

Exploring the cardiovascular disease continuum: blood pressure and target organ damage

Introduction The objectives of this thesis are to: (1) examine how ambulatory blood pressure monitoring (ABPM) refines office blood pressure (BP) measurement; (2) determine if absolute ambulatory BP or dipping status is better associated with target organ damage (TOD); (3) explore the association of isolated nocturnal hypertension (INH) with TOD; and (4) investigate the association of night-time BP with ultrasound markers of cardiovascular damage. Methods Data from the Mitchelstown Cohort Study was analysed to deliver objectives 1 and 2. Objective 3 was addressed by a systematic review and analysis of data from the Mitchelstown Study. A sample of participants from the Mitchelstown Study underwent an echocardiogram for speckle tracking analysis and carotid ultrasound to achieve objective 4. Results ABPM reclassifies hypertension status in approximately a quarter of individuals, with white coat and masked hypertension prevalence rates of 11% and 13% respectively. Night-time systolic BP is better associated with TOD than daytime systolic BP and dipping level. In multi-variable models the odds ratio (OR) for LVH was 1.4 (95% CI 1.1 -1.8) and for albumin:creatinine ratio ≥ 1.1 mg/mmol was 1.5 (95% CI 1.2 – 1.8) for each 10 mmHg rise in night-time systolic BP. The evidence for the association of INH with TOD is inconclusive. Night-time systolic BP is significantly associated with global longitudinal strain (GLS) (beta coefficient 0.85 for every 10 mmHg rise, 95% CI 0.3 – 1.4) and carotid plaques (OR 1.9 for every 10 mmHg rise, 95% CI 1.1 – 3.2) in univariable analysis. The findings persist for GLS in sex and age adjusted models but not in multivariable models. Discussion Hypertension cannot be effectively managed without using ABPM. Night-time systolic BP is better associated with TOD than daytime systolic BP and dipping level, and therefore, may be a better therapeutic target in future studies.

Asymmetric polygons with maximum area

We say that a polygon inscribed in the circle is asymmetric if it contains no two antipodal points being the endpoints of a diameter. Given n diameters of a circle and a positive integer k < n, this paper addresses the problem of computing a maximum area asymmetric k-gon having as vertices k < n endpoints of the given diameters. The study of this type of polygons is motivated by ethnomusiciological applications.

Desenvolver a consciência fonológica na educação pré-escolar : potencialidades da exploração da diversidade linguística

O presente trabalho centra-se no desenvolvimento de um projeto de sensibilização à diversidade linguística e cultural, intitulado “Por ritmos nunca dantes navegados”, numa sala de um jardim de infância português, tendo como finalidade avaliar e compreender o desenvolvimento da consciência fonológica de um grupo de doze crianças entre os 3 e os 4 anos de idade. Para o efeito, recorremos a uma metodologia mista, que se traduziu em procedimentos de tipo quantitativo e qualitativo de recolha e análise de dados: no primeiro caso, recorremos a testes de consciência fonológica e de discriminação auditiva, aplicados a um grupo experimental e a um grupo de controlo de seis crianças antes e após as sessões de sensibilização; no segundo caso, recorremos à observação direta e à vídeo gravação das quatro sessões do projeto. A análise dos dados recolhidos, realizada através de análise estatística e de conteúdo, permitiu alcançar resultados relevantes, tendo-se registado um desenvolvimento significativo das capacidades de discriminação auditiva e de consciência fonológica (silábica e da palavra) do grupo experimental que esteve presente nas sessões de sensibilização. Os resultados da análise estatística parecem sugerir que o contacto com línguas diferentes, através de atividades de sensibilização, contribui para a descoberta de unidades segmentais das línguas, essenciais para realizar tarefas de discriminação auditiva e de consciência fonológica. A análise de conteúdo ajudou a corroborar os resultados obtidos nos testes de discriminação auditiva e de consciência fonológica, tendo as crianças do grupo experimental revelado, nas suas interações, ser capazes de discriminar sons, bem como segmentar e manipular palavras e sílabas. Estes resultados sustentam a importância das abordagens plurais na educação pré-escolar, pois o contacto com sonoridades, línguas e palavras diferentes faz com que a criança atente no objeto-língua, realizando sobre ele múltiplas e ricas atividades para o desenvolvimento de competências metalinguísticas e também sociais.

Clustering through post inhibitory rebound in synaptically coupled neurons

Post inhibitory rebound is a nonlinear phenomenon present in a variety of nerve cells. Following a period of hyper-polarization this effect allows a neuron to fire a spike or packet of spikes before returning to rest. It is an important mechanism underlying central pattern generation for heartbeat, swimming and other motor patterns in many neuronal systems. In this paper we consider how networks of neurons, which do not intrinsically oscillate, may make use of inhibitory synaptic connections to generate large scale coherent rhythms in the form of cluster states. We distinguish between two cases i) where the rebound mechanism is due to anode break excitation and ii) where rebound is due to a slow T-type calcium current. In the former case we use a geometric analysis of a McKean type model to obtain expressions for the number of clusters in terms of the speed and strength of synaptic coupling. Results are found to be in good qualitative agreement with numerical simulations of the more detailed Hodgkin-Huxley model. In the second case we consider a particular firing rate model of a neuron with a slow calcium current that admits to an exact analysis. Once again existence regions for cluster states are explicitly calculated. Both mechanisms are shown to prefer globally synchronous states for slow synapses as long as the strength of coupling is sufficiently large. With a decrease in the duration of synaptic inhibition both systems are found to break into clusters. A major difference between the two mechanisms for cluster generation is that anode break excitation can support clusters with several groups, whilst slow T-type calcium currents predominantly give rise to clusters of just two (anti-synchronous) populations.

Verteilungsmuster der Mesofauna im hohen Ober-Hauterive Nordwestdeutschlands

The vertical distribution pattem of mesofaunal elements is described from clay-marl bedding rhythms from the Frielingen section (Hannover, NW Germany), which exposes latest Hau- terivian sediments (early Cretaceous). Some mesofaunal groups show a correlation with the pale- dark bedding rhythms. The pale, marly beds are chracterised by bryozoans. In addition remnants of crinoids, echinoids, asteroids, ophiuroids and holothuroids are more common in pale layers than in dark ones. Converseley, the relative abundance of serpulids, fish remains, bivalves and gastropods shows no relationship to the bedding rhythms.

Global slowing of network oscillations in mouse neocortex by diazepam

SCHEFFZUK, C. , KUKUSHKA, V. , VYSSOTSKI, A. L. , DRAGUHN, A. , TORT, A. B. L. , BRANKACK, J. . Global slowing of network oscillations in mouse neocortex by diazepam. Neuropharmacology , v. 65, p. 123-133, 2013.

Theta-associated high-frequency oscillations (110–160 Hz) in the hippocampus and neocortex

TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. . Theta-associated high-frequency oscillations (110-160 Hz) in the hippocampus and neocortex. Progress in Neurobiology , v. 100, p. 1-14, 2013.

Selective Coupling between Theta Phase and Neocortical Fast Gamma Oscillations during REM-Sleep in Mice

TORT, A. B. L. ; SCHEFFER-TEIXEIRA, R ; Souza, B.C. ; DRAGUHN, A. ; BRANKACK, J. . Theta-associated high-frequency oscillations (110-160 Hz) in the hippocampus and neocortex. Progress in Neurobiology , v. 100, p. 1-14, 2013.

Petr Eben's oratorio Apologia Sokratus (1967) and ballet Curses and Blessings (1983): An interpretative analysis of the symbolism behind the text settings and musical style

The Czech composer Petr Eben (1927-2007) has written music in all genres except symphony, but he is highly recognized for his organ and choral compositions, which are his preferred genres. His vocal works include choral songs and vocal-instrumental works at a wide range of difficulty levels, from simple pedagogical songs to very advanced and technically challenging compositions. This study examines two of Eben‘s vocal-instrumental compositions. The oratorio Apologia Sokratus (1967) is a three-movement work; its libretto is based on Plato‘s Apology of Socrates. The ballet Curses and Blessings (1983) has a libretto compiled from numerous texts from the thirteenth to the twentieth centuries. The formal design of the ballet is unusual—a three-movement composition where the first is choral, the second is orchestral, and the third combines the previous two played simultaneously. Eben assembled the libretti for both compositions and they both address the contrasting sides of the human soul, evil and good, and the everlasting fight between them. This unity and contrast is the philosophical foundation for both compositions. The dissertation discusses the multileveled meanings behind the text settings and musical style of the oratorio and ballet in analyses focusing on the text, melodic and harmonic construction, and symbolism. Additional brief analyses of other vocal and vocal-instrumental compositions by Eben establish the ground for the examination of the oratorio and ballet and for understanding features of the composer‘s musical style. While the oratorio Apologia Sokratus was discussed in short articles in the 1970s, the ballet Curses and Blessings has never previously been addressed within Eben scholarship. The dissertation examines the significant features of Eben‘s music. His melodic style incorporates influences as diverse as Gregorian chant and folk tunes on the one hand, and modern vocal techniques such as Sprechgesang and vocal aleatoricism on the other. His harmonic language includes bitonality and polytonality, used to augment the tonal legacy of earlier times, together with elements of pitch collections and limited serial procedures as well as various secundal and quartal harmonic sonorities derived from them. His music features the vibrant rhythms of folk music, and incorporates other folk devices like ostinato, repetitive patterns, and improvisation.

Um percurso vivido com um grupo heterogéneo de 3 e 4 anos

Relatório de Estágio apresentado à Escola Superior de Educação de Paula Frassinetti para a obtenção de grau de Mestre em Educação Pré-Escolar

Plasticity in Insect Olfaction: To Smell or Not to Smell?

International audience

Test-Retest Reliability of Resting-State Magnetoencephalography Power in Sensor and Source Space

Several studies have reported changes in spontaneous brain rhythms that could be used asclinical biomarkers or in the evaluation of neuropsychological and drug treatments in longitudinal studies using magnetoencephalography (MEG). There is an increasing necessity to use these measures in early diagnosis and pathology progression; however, there is a lack of studies addressing how reliable they are. Here, we provide the first test-retest reliability estimate of MEG power in resting-state at sensor and source space. In this study, we recorded 3 sessions of resting-state MEG activity from 24 healthy subjects with an interval of a week between each session. Power values were estimated at sensor and source space with beamforming for classical frequency bands: delta (2–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), low beta (13–20 Hz), high beta (20–30 Hz), and gamma (30–45 Hz). Then, test-retest reliability was evaluated using the intraclass correlation coefficient (ICC). We also evaluated the relation between source power and the within-subject variability. In general, ICC of theta, alpha, and low beta power was fairly high (ICC > 0.6) while in delta and gamma power was lower. In source space, fronto-posterior alpha, frontal beta, and medial temporal theta showed the most reliable profiles. Signal-to-noise ratio could be partially responsible for reliability as low signal intensity resulted inhigh within-subject variability, but also the inherent nature of some brain rhythms in resting-state might be driving these reliability patterns. In conclusion, our results described the reliability of MEG power estimates in each frequency band, which could be considered in disease characterization or clinical trials.