FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A sÃndrome alimentar noturna (SAN) à um distÃrbio alimentar caracterizada por um atraso no ritmo circadiano de apetite-saciedade, com ingestÃo calÃrica ≥ 25% do total diÃrio apÃs a refeiÃÃo da noite e / ou pelo menos trÃs despertares noturnos acompanhados de alimentaÃÃo por semana. O Night Eating à um instrumento, que contÃm 14 itens com cinco pontos, usado como triagem para o diagnÃstico da SAN. O principal objetivo deste estudo foi traduzir para o portuguÃs a versÃo em inglÃs, atualizada, do Night Eating Questionnaire e adaptÃ-la culturalmente para uso em pacientes brasileiros. Na primeira etapa do estudo, foi realizada traduÃÃo; retrotraduÃÃo para o InglÃs; revisÃo das traduÃÃes e avaliaÃÃo da equivalÃncia semÃntica. Em seguida, avaliou-se a reprodutibilidade intra e interobservador num grupo de 37 indivÃduos. A confiabilidade do questionÃrio foi avaliada pelo coeficiente de Cronbach em 90 indivÃduos. A escala brasileira apresentou excelente consistÃncia interna, com coeficiente alfa ligeiramente inferior a 0,9. A escala traduzida e adaptada apresentou ainda adequada reprodutibilidade intra-observador com coeficientes entre 0,95 e 1,0 e interobservador com coeficientes entre 0,92 e 1,0. Estes resultados mostram que o instrumento traduzido tem clareza e que conduz a respostas consistentes, que nÃo se confundem com o passar do tempo. Desse modo, ficam estabelecidas a equivalÃncia conceitual dos itens e a equivalÃncia operacional das versÃes em portuguÃs e inglÃs. Novos estudos da aplicabilidade da versÃo brasileira utilizando amostras estratificadas por escolaridade, faixa de renda e classe social deverÃo ser realizados para avaliar este instrumento de forma mais precisa. / Night eating syndrome (NES) is an eating disorder characterized by a delay in the circadian time of food intake, with more than 25% of daily caloric intake after the evening meal or at least 3 nocturnal awakenings with ingestion per week. The Night Eating Questionnaire (NEQ) has 14 items with a 5 point scale and has been used as a tool for NES evaluation. The main objective of this study was to translate the current English version of the NEQ into Portuguese and adapting to cultural differences to allow for its use in Brazilian patients. The first part of the study consisted of translation; back-translation to English; review of the translations and evaluation of semantic equivalence. After this initial phase, intra and inter-observer reproducibility was assessed in a group of 37 individuals. The reliability of the questionnaire was evaluated by the Cronbach coefficient in 90 individuals. The translated and adapted version showed excellent internal consistency, with an alfa coefficient slightly below 0.9. This new version also had adequate reproducibility both intra-observer, with coefficients between 0.95 and 1.0, and inter-observer, with coefficients between 0.92 and 1.0. These results show that the translated questionnaire is clear, and the answers elicited are consistent and remain stable over time. Therefore, equivalence of the concepts in each item and operational equivalence of the English and Portuguese versions are established. Future studies evaluating the applicability of the Brazilian version using samples stratified by schooling, income and social status are necessary for a more precise evaluation of this tool.

O sistema circadiano das aves é composto pela retina, a região homóloga aos núcleos supraquiasmáticos de mamíferos (NSQ) e a glândula pineal. A retina apresenta muitos eventos fisiológicos rítmicos, como por exemplo os movimentos das células fotorreceptoras em vertebrados não mamíferos, a expressão de opsinas, regeneração do cromóforo visual e produção e liberação de melatonina e dopamina. Todos estes eventos rítmicos são coordenados para prever alterações nas condições luminosas que ocorrem durante o dia, otimizando a função retiniana. Neste trabalho foi investigada a expressão de componentes chave de um sistema circadiano, incluindo os dois genes de melanopsina, Opn4x e Opn4m, os genes de relógio Clock e Per2, e os genes das enzimas chave da síntese de melatonina, N-Acetiltransferase, e de dopamina, Tirosina Hidroxilase, em células da retina de embriões de galinha. Culturas primárias de retina de embriões de galinha com 8 dias foram preparadas no ZT0 (quando as luz é acesa) e semeadas na densidade de 107 células por frasco de 25 cm2 . As células foram mantidas em ambiente úmido, com 5% CO2, a 40o C, em escuro constante, fotoperíodo 12C:12E, fotoperíodo 12C:12E seguido de escuro constante, ou em escuro constante na presença e na ausência de glutamato 100 μM por 12 h. A extração de RNA total foi feita ao longo de 24 horas com intervalo de três horas tendo início no ZT0 do sexto dia. As amostras foram submetidas a RT-PCR seguido de PCR quantitativo para a quantificação de RNAm. Para confirmar a expressão da proteína OPN4x foi realizado ensaio imunohistoquímico com anticorpos anti-melanopsina de galinha desenvolvidos em coelho. Também foi feita a quantificação da concentração das proteínas OPN4x, CLOCK e TIROSINA HIDROXILASE através da técnica de Western Blot. A quantificação do RNAm em escuro constante não apresentou ritmos de transcrição para nenhum gene. Já as células mantidas em fotoperíodo 12C:12E apresentaram padrões rítmicos de transcrição para Clock, Per2, Opn4m, N-Acetiltransferase e Tirosina Hidroxilase. Glutamato 100 μM foi eficaz em induzir ritmo em Clock, e inibiu drasticamente a expressão de Tirosina Hidroxilase e, apenas mais pontualmente, de Opn4x e Opn4m. Ensaios de viabilidade celular e fragmentação de DNA por citometria de fluxo demonstraram que essa inibição não foi resultante de ação tóxica ou apoptótica do glutamato. O neurotransmissor não teve qualquer efeito sobre a transcrição de Per2 e de N-Acetiltransferase. A quantificação protéica não indicou a presença de ritmo para CLOCK, OPN4x ou TIROSINA HIDROXILASE. A grande variabilidade inter-ensaios nos resultados de quantificação protéica sugere uma menor sensibilidade e precisão para esse método, quando comparado a PCR quantitativo. Nossos resultados indicam que as células de retina de embrião de 8 dias de galinha em cultura já contêm um relógio funcional, porém, este necessita do ciclo claro-escuro ou glutamato para sua sincronização. / The avian circadian system is composed by the retina, the mammalian homolog region of the supra-chiasmatic nucleus (SNC) and the pineal gland. The retina itself shows many rhythmic physiological events, such as movements of photoreceptor cells, opsin expression, retinaldehyde re-isomerization, melatonin and dopamine production and release. Altogether these rhythmic events are coordinated to predict environmental changes in light conditions during the day, optimizing retina function. In this work we investigated the expression of key components of a circadian system, including the two melanopsin genes, Opn4x, Opn4m, as well as the Clock, Per2, N-Acetyltransferase and Tyrosine Hidroxylase genes in chick embryo retinal cells. Primary cultures of chicken retina from 8-day-old embryos were prepared at ZT0 (lights on) and seeded at the density of 107 cells per 25 cm2 culture flask. The cells were kept in a humidified incubator in a 5% CO2 atmosphere at 40o C in constant dark, in 12L:12D, in 12L:12D followed by constant dark, or in constant dark in the absence or presence of 100 μM glutamate for 12 h starting at ZT0 of the fifth day in vitro. Total RNA extraction was performed along 24 hours every three hours starting at ZT0 of the sixth day. The samples were submitted to RT-PCR followed by quantitative PCR for mRNA quantification. To analyze the Opn4x expression in these cells we performed an immunocytochemistry analysis with antibodies anti-chicken melanopsin developed in rabbit. We also quantified the protein levels of OPN4x, CLOCK AND TYROSINE HYDROXYLASE by Western Blot. The mRNA quantification showed no rhythm of transcription for any gene in cells kept in constant dark. However under a light-dark cycle, Clock, Per2, Opn4m, N-Acetyltransferase and Tyrosine Hydroxylase presented rhythm patterns of transcription. 100 μM glutamate was able to induce rhythmic expression of Clock, and strongly inhibited the expression of Tyrosine Hydroxylase and, just punctually, of Opn4x and Opn4m. Assays of cell viability and DNA fragmentation using flow cytometry demonstrated that the inhibition did not result of glutamate toxic or apoptotic actions. The neurotransmitter had no effect on Per2 and N-Acetyltransferase transcription. Protein quantification by Western Blot showed no rhythmic oscillation of CLOCK, OPN4x or TYROSINE HYDROXYLASE. The great variability inter-assays seen in the results of protein quantification suggests that this method is less precise and sensitive than quantitative PCR. The present data show evidences that chicken embryonic retinal cells contain a functional circadian Clock. However light-dark cycle or glutamate stimuli are needed to its synchronization.

Este trabalho consiste em um estudo métrico e rítmico das Odes Píticas de Píndaro, bem como uma tradução desses mesmos poemas com o objetivo de reproduzir os aspectos métricos e rítmicos identificados durante o estudo. Trata-se, portanto, de uma abordagem que privilegia não o sentido, como se faz de costume no âmbito acadêmico, mas, sim, alguns elementos formais bem específicos (o metro e o ritmo), os quais são caros ao tema central da tese que defendemos: a da unidade rítmica nos epinícios aqui estudados. / This work is comprised of a metrical and rhythmical study of Pindar\'s Pythian Odes, as well as a translation of said poems with a view to reproduce the metrical and rhythmical aspects that were identified during the study. Hence, this approach focuses not on the meaning of the poems, as it is usually done in the academy, but on specific formal elements (meter and rhythm) that are dear to this thesis\' central theme: the rhythmic unity of these victory odes.

Orientador: Everardo Magalhães Carneiro / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T14:27:08Z (GMT). No. of bitstreams: 1 Borck_PatriciaCristine_M.pdf: 1384245 bytes, checksum: 89fa526347ae455e0cfcf6e3bd414018 (MD5) Previous issue date: 2014 / Resumo: Os processos fisiológicos como ciclo sono-vigília e o metabolismo estão sujeitos a oscilações circadianas e são regulados por um conjunto de genes conhecidos como genes do relógio, ou clock genes. Mutação nesses genes em camundongos reduz a secreção de insulina e a proliferação das células ? pancreáticas promovendo intolerância a glicose e hiperglicemia. Distúrbios nutricionais em fases iniciais da vida estão associados com o aparecimento do Diabetes Mellitus tipo 2 na vida adulta. Camundongos submetidos a restrição proteica intrauterina apresentam expressão alterada dos clock genes e maior suscetibilidade ao ganho de peso e intolerância a glicose. Neste trabalho tivemos como objetivo determinar a expressão diária dos clock genes em tecidos periféricos, hipotálamo e ilhotas pancreáticas de camundongos submetidos a restrição proteica. Avaliamos também o perfil oscilatório da secreção de insulina estimulada por glicose e pelo agonista colinérgico carbacol nesse modelo animal. Camundongos submetidos a restrição proteica (R) apresentaram características típicas de desnutrição como menor peso corpóreo, hipoinsulinemia, hipoproteinemia e maior tolerância a glicose e a insulina. Camundongos R apresentaram maior consumo alimentar, acompanhado de alterações no perfil oscilatório de genes hipotalâmicos Pomc (Pro-opiomelanocortina) e Npy (Neuropeptídeo Y). Nesse tecido, somente o gene do relógio Rev-erb? teve sua expressão influenciada pela restrição proteica. Camundongos R apresentaram, no fígado e músculo perda do perfil oscilatório para os genes Bmal1 e Clock. Ainda, no fígado e ilhotas pancreáticas a expressão de Rev-erb? foi alterada, com redução no conteúdo de mRNA. Em relação ao gene Per1, camundongos R exibiram adiantamento na expressão desse gene no tecido adiposo. No músculo e ilhotas houve perda da oscilação diária para esse gene. Camundongos R exibiram, no músculo e tecido adiposo, adiantamento na expressão do gene Per2. Ilhotas isoladas de camundongos controle (C) apresentaram padrão oscilatório de secreção de insulina sendo os maiores níveis atingido nos ZT 2 e 14 e redução no ZT 8. Contudo, camundongos R apresentaram redução na secreção de insulina estimulada por glicose, e perda do seu perfil oscilatório. O grupo R não apresentou alteração na liberação de insulina na presença do agonista e antagonista de Rev-erb?. Além disso, a expressão dos genes Sintaxina, Sinaptotagmina, e Insulina, estão reduzidos em camundongos R. O grupo R também apresentou perda oscilatória da secreção de insulina na presença de glicose associada ao Carbacol e redução na expressão do Receptor Muscarínico de Acetilcolina. Com os presentes resultados podemos concluir que camundongos submetidos a restrição proteica apresentaram características típicas de desnutrição com alteração na homeostase glicêmica e secreção de insulina. Ademais, camundongos R exibiram perda do perfil de secreção desse hormônio ao longo de 24 horas, o qual está relacionado com as alterações na expressão de Rev-erb?. Além disso, houve alteração no perfil de expressão dos genes clock, em especial Rev-erb?, Per1 e Per2 nos tecidos periféricos, fato que pode estar relacionado com as alterações na tolerância a glicose e insulina em camundongos R / Abstract: The physiological processes such as sleep-wake cycle and metabolism are subject to circadian fluctuations and are regulated by a group of genes known as clock genes or genes clock. Mutations in these genes in mice reduces insulin secretion and ?-pancreatic cell proliferation promoting impaired glucose tolerance and hyperglycemia. Nutritional disorders in the early stages of life are associated with the onset of type 2 diabetes in adulthood. Mice subjected to intrauterine protein restriction have altered expression of clock genes and increased susceptibility to weight gain and glucose intolerance. In this study we aimed to determine the daily expression of clock genes in peripheral tissues, hypothalamus and pancreatic islets of mice subjected to protein restriction. We also evaluated the oscillatory profile of the glucose stimulated insulin secretion and the cholinergic agonist carbachol in this animal model. Mice subjected to protein restriction (R) showed typical features of malnutrition as lower body weight , hypoinsulinemia , hypoproteinemia and increased glucose tolerance and insulin. R mice had higher food consumption, accompanied by changes in the oscillatory profile to Pomc and Npy gene in the hypothalamus. In this tissue, only the expression Rev- erb? gene was influenced by protein restriction. Mice R showed in the liver and muscle loss of the oscillatory profile to Clock and Bmal1 gene. Still, in liver and pancreatic islets the expression of Rev- erb? was changed, with reduction in mRNA content. Regarding the Per1 gene, R mice exhibited advance in the expression of this gene in adipose tissue. In muscle and islets there was loss of daily fluctuation for this gene. R mice exhibited, muscle and adipose tissue, in advance of Per2 gene expression. Islets isolated from control mice (C) showed oscillatory pattern of insulin secretion with the highest levels attained in the ZT 2 e 14 and reduction in the ZT 8. However, R mice had reduced glucose stimulated insulin secretion and loss of its oscillatory profile. R group showed no change in insulin release in the presence of Rev- erb? agonist and antagonist. Furthermore, the expression of Syntaxin, Synaptotagmin, and Insulin genes are reduced in R mice. R group also exhibited oscillatory loss of insulin secretion in the presence of glucose linked Carbachol and the reduction in the expression of Muscarinic Acetylcholine Receptor. With these results we can conclude that mice subjected to protein restriction showed typical features of malnutrition with alterations in glucose homeostasis and insulin secretion. Moreover, R mice exhibited loss of secretion of this hormone profile over 24 hours, which is associated with changes in the expression of Rev- erb?. In addition, there were changes in expression profile of clock genes, especially Rev-erb?, Per1 and Per2 in peripheral tissues, which may be related to changes in glucose tolerance and insulin in R mice / Mestrado / Fisiologia / Mestra em Biologia Funcional e Molecular

Sleep disturbance and behavioural difficulties are both prevalent problems in the intellectual and developmental disability population and can have a significant impact on quality of life for the individual and their family. This thesis investigated sleep, behaviour and circadian rhythm functioning in children with intellectual and developmental disabilities, and is presented in three sections. The first two papers have been prepared in accordance with the author guidelines of the journals proposed for submission, excluding tables and figures for ease of reading. The first paper is a systematic review of the literature examining the relationship between sleep disturbance and challenging behaviour in children with intellectual and developmental disabilities. 15 studies were included in the review and overall there were consistent findings of an association between the presence of sleep disruption and increased behavioural difficulties. A causal relationship could not be inferred due to the cross-sectional methodology of studies. Other factors, such as parental wellbeing, child level of intellectual disability and comorbidity of physical health conditions, need to be considered to understand the complexity of this relationship. Children with the neurodevelopmental disorder mucopolysaccharidosis type III (MPS III or Sanfilippo syndrome) present with high rates of sleep disturbance and challenging behaviour. The second paper investigates circadian rhythm functioning and activity levels in children with MPS III, compared to typically developing controls. Objective measurement of circadian rhythm and activity levels was obtained through actigraphic recording for 7-10 days. Children with MPS III had increased fragmentation of circadian rhythm, less stability of rhythm in relation to external cues and a differential pattern of activity across the day compared to controls. Overall, results were indicative of a disruption of circadian rhythm function in children with MPS III. The implications for clinical practice and future research are discussed. The third paper provides a critical appraisal of the overall research process, including further consideration of the strengths and limitations, implications for clinical practice, wider context of the research and personal reflections. An account of the project that was originally proposed with the MPS III population is also presented, alongside reflections on its termination.

TEETH AND OTHER TALES is a novella and a collection of short stories that explore the blurry lines between illusion and reality. Teeth, the novella, is narrated backward in time, chronicling the life of Lucy from the age of sixty-five back to seventeen. After years of surviving an oppressive marriage, Lucy escapes her husband, but in doing so abandons her three children. In order to rationalize her decisions, Lucy uses selective memory to create her own reality to the extent that she comes to believe her own delusions. The four short stories in the collection feature protagonists who create their own personal myths and struggle to protect their distorted truths, with mixed results. These struggles between the “real,” as conventionally defined, and personal fictions are complicated by elements of magical realism and surrealism. The stories were influenced by the short fiction of Nikolai Gogol, Franz Kafka and Haruki Murakami.

Experimental phonetic research on speech rhythm seems to have reached an impasse. Recently, this research field has tended to investigate produced (rather than perceived) rhythm, focussing on timing, i.e. duration as an acoustic cue, and has not considered that rhythm perception might be influenced by native language. Yet evidence from other areas of phonetics, and other disciplines, suggests that an investigation of rhythm is needed which (i) focuses on listeners' perception, (ii) acknowledges the role of several acoustic cues, and (iii) explores whether the relative significance of these cues differs between languages. This thesis, the originality of which derives from its adoption of these three perspectives combined, indicates new directions for progress. A series of perceptual experiments investigated the interaction of duration and f0 as perceptual cues to prosody in languages with different prosodic structures - Swiss German, Swiss French, and French (i.e. from France). The first experiment demonstrated that a dynamic f0 increases perceived syllable duration in contextually isolated pairs of monosyllables, for all three language groups. The second experiment found that dynamic f0 and increased duration interact as cues to rhythmic groups in series of monosyllabic digits and letters; the two cues were significantly more effective than one when heard simultaneously, but significantly less effective than one when heard in conflicting positions around the rhythmic-group boundary location, and native language influenced whether f0 or duration was the more effective cue. These two experiments laid the basis for the third, which directly addressed rhythm. Listeners were asked to judge the rhythmicality of sentences with systematic duration and f0 manipulations; the results provide evidence that duration and f0 are interdependent cues in rhythm perception, and that the weighting of each cue varies in different languages. A fourth experiment applied the perceptual results to production data, to develop a rhythm metric which captures the multi-dimensional and language-specific nature of perceived rhythm in speech production. These findings have the important implication that if future phonetic research on rhythm follows these new perspectives, it may circumvent the impasse and advance our knowledge and model of speech rhythm.

This study investigated relationships between 36 predictor variables and ensemble pitch and rhythm error discrimination ability. Precollege musical background and other demographic data were collected by means of the Musical Background Questionnaire. Musical achievement was measured by the Aliferis-Stecklein Music Achievement Test, College Midpoint Level. Undergraduate musical coursework data were obtained from transcripts. The criterion variables were measured by the Ramsey-Vincent Test of Instrumental Error Detection; a test of aural-visual pitch and rhythm error discrimination for full-score band music of medium difficulty. All three instruments were administered to 82 undergraduate music students. Subjects represented three Canadian universities and two community colleges. Pearson product-moment correlation tests were used to identify variables significantly related to musical ensemble error discrimination at the .10 level of significance. Eighteen variables were found to be significantly related to ensemble pitch error discrimination. Fourteen variables were found to be significantly related to ensemble rhythm error discrimination. Regression procedures were performed for each of the significant variables. These variables were then organized into blocks representing precollege musical background, other demographic variables, musical achievement, and undergraduate coursework. Regressions were performed for each of the blocks. Musical achievement, precollege musical background, demographic, and undergraduate coursework blocks of variables accounted for 5, 15, 35, and 21 percent of the variance in ensemble pitch error discrimination scores respectively. Musical achievement, precollege musical background, demographic, and undergraduate coursework blocks of variables accounted for 21, 16, 19, and 12 percent of the variance in ensemble rhythm error discrimination scores respectively. Combinations of variables from these blocks produced a linear model comprised of five demographic variables plus precollege choral experience that accounted for 42 percent of the variance in ensemble pitch error discrimination scores. Combinations of variables from the four blocks produced a linear model of ensemble rhythm error discrimination comprised of rhythmic discrimination, choice of a band instrument as one's major performance medium, composition as one's program major, and precollege band or orchestral experience. These four variables accounted for 32 percent of the variance in ensemble rhythm error discrimination scores. The variables selected for use in this study accounted for a substantial portion of the variance in error discrimination scores. To improve the predictive power of future studies, other variables need to be identified and included in the model. Ten conclusions were made regarding the prediction of ensemble error prediction ability. Three recommendations were made for improving error discrimination training and seven recommendations were made for future research in ensemble error discrimination. / Education, Faculty of / Graduate

The thesis presents a series of papers exploring catatonic symptoms and circadian rest-activity levels in autistic spectrum disorders (ASD). The thesis is presented in paper-based format and encompasses a literature review, an empirical paper and a critical appraisal. Paper 1 is a systematic review of available treatments for autistic catatonia. Catatonic symptoms are thought to occur in around 8% of young people with ASD, and it has been suggested that biological timing abnormalities may play a key role in the development of these difficulties. Twenty two papers were included in the final review, detailing treatment of a total of 28 cases of autistic catatonia. Both adult and paediatric cases were included. The range of treatments described encompassed electroconvulsive therapy, various psychotropic medications, behavioural and sensory therapies. The review highlights limitations in the available literature and suggests avenues for future research. Paper 2 explores circadian patterns in activity using actigraphy. A case series of 8 young people with an ASD diagnosis were recruited from specialist schools and asked to wear an actigraph for one week. Parents completed questionnaire measures of ASD traits and symptoms of autistic catatonia. Findings indicated a high degree of variability in circadian rest-activity cycles, both between participants and across the week. The study findings have implications for future research into circadian rest-activity levels in this population, as well as possible therapeutic applications. The final paper in the thesis presents a critical appraisal of the research, including discussion of strengths and limitations of the work, theoretical and clinical implications and directions for future research. Some personal reflections on the process of conducting the research are also included.

This thesis addresses some theoretical issues generated by the results of recent analysis of EEG time series proving the brain dynamics are driven by abrupt changes making them depart from the ordinary Poisson condition. These changes are renewal, unpredictable and non-ergodic. We refer to them as crucial events. How is it possible that this form of randomness be compatible with the generation of waves, for instance alpha waves, whose observation seems to suggest the opposite view the brain is characterized by surprisingly extended coherence? To shed light into this apparently irretrievable contradiction we propose a model based on a generalized form of Langevin equation under the influence of a periodic stimulus. We assume that there exist two different forms of time, a subjective form compatible with Poisson statistical physical and an objective form that is accessible to experimental observation. The transition from the former to the latter form is determined by the brain dynamics interpreted as emerging from the cooperative interaction among many units that, in the absence of cooperation would generate Poisson fluctuations. We call natural time the brain internal time and we make the assumption that in the natural time representation the time evolution of the EEG variable y(t) is determined by a Langevin equation perturbed by a periodic process that in this time representation is hardly distinguishable from an erratic process. We show that the representation of this random process in the experimental time scale is characterized by a surprisingly extended coherence. We show that this model generates a sequence of damped oscillations with a time behavior that is remarkably similar to that derived from the analysis of real EEG's. The main result of this research work is that the existence of crucial events is not incompatible with the alpha wave coherence. In addition to this important result, we find another result that may help our group, or any other research group working on the analysis of brain's dynamics, to prove or to disprove the existence of crucial events. We study the diffusion process generated by fluctuations emerging from the same model after filtering out the alpha coherence, and we study the recursion to the origin. We study the survival probability of this process, namely the probability that up to a given time no re-crossing of the origin occurs. We find that this is an inverse power law with a power that depends on whether or not crucial events exist.