Muitos trabalhos sobre comportamento consideram que os ritmos observados são simplesmente uma resposta aos estímulos ambientais. No entanto, desde o século XVIII, sabe-se que a temporização é real e muitos organismos exibem ritmos endógenos que são arrastados por zeitgebers ou \"doadores de tempo\". Para a grande maioria dos seres vivos, o principal zeitgeber é o ciclo claro/escuro (CE). No entanto, para os organismos das zonas entremarés, o ciclo das marés é tão importante quanto o ciclo de luz. A maré e seus componentes agindo como zeitgeber têm sido estudados com invertebrados e pouca atenção tem sido dada aos peixes que vivem nas zonas entremarés. Uma das espécies mais comuns destes ambientes é o Bathygobius soporator, conhecido como amborê, e o presente trabalho teve como objetivo verificar a presença de ritmicidade em sua atividade locomotora, avaliando as contribuições endógenas e exógenas dos ciclos de luminosidade, da variação da coluna d\'água e da turbulência da água sobre este ritmo. Para isso, os amborês foram mantidos em aquários individuais onde as condições abióticas puderam ser controladas de acordo com os experimentos em andamento. A atividade locomotora foi registrada com câmeras de segurança e fontes de luz infravermelha acopladas a um vídeo \"time-lapse\" que fez o registro de um quadro a cada trinta segundos. As distâncias percorridas a cada trinta segundos foram categorizadas em quatro classes discretas, e esses valores foram agrupados a cada trinta minutos, compondo 48 pontos a cada 24 horas. A análise das séries temporais foi feita através do programa \"El Temps\" que gerou actogramas e periodogramas de Lomb-Scargle, que permitem identificar ritmos com períodos significativos. Diante dos resultados obtidos, pôde-se concluir que o ciclo CE e de variação na coluna d\'água são zeitgebers, enquanto a turbulência é um agente mascarador para a ritmicidade locomotora dos amborês. Concluiu-se, também, que os relógios biológicos nos amborês não são rígidos e possuem acoplamento extremamente frágil, gerando uma alta plasticidade na expressão dos ritmos endógenos e exógenos, o que está de acordo com o modo de vida dos amborês observados no ambiente natural. / Many organisms\' rhythms are considered to be simple reactions to the cyclical changes in the environment. However, the endogenous rhythms entrained by zeitgebers are well known and have been described for many organisms since the 18th century. Although the light/dark cycle (LD) is the main zeitgeber for most living beings, the tidal cycles are as important for the intertidal organisms. It has been studied as a zeitgeber mainly for invertebrates, and little attention has been given to the intertidal fish. Bathygobius soporator, also known as frillfin goby, is one of the most abundant species in the tropical intertidal zone, and this project was designed to verify the rhythmicity in its locomotor activity, and measure how the LD cycle, the cyclical change in water level, and the turbulence cycle affect the endogenous and/or exogenous aspects of this rhythm. The gobies were kept in individual aquariums where all abiotic conditions were controlled according to the requirements of each experiment. The locomotor activity was recorded with security cameras and infrared light bulbs connected to a time-lapse video recorder that taped one frame every thirty seconds. The distance moved by each fish every thirty seconds was categorized into four discrete classes. The values assigned to these classes of movements were added into thirty minutes blocks, thus giving 48 numbers for every 24 hours. The collected data was analyzed by the \"El Temps\" software that provided actograms and Lomb-Scargle periodograms which allowed the detection of rhythms and significant periods. The results led us to conclude that LD cycle and the cyclical change in water level are zeitgebers to locomotor activity of B. soporator, and that the turbulence is a masking agent. We could also affirm that the frillfin gobies\' biological clocks are weak and have a very fragile coupling, giving the fish a malleable expression of their endogenous and exogenous rhythms. This concurs with the natural history of B. soporator.

As glândulas salivares são glândulas exócrinas que vertem seus produtos para cavidade oral. As principais glândulas são as parótidas, sublinguais e submandibulares sendo elas as responsáveis pela contribuição do maior volume de saliva durante o processo de secreção que, assim como todas as atividades que nosso corpo exerce, também dependem de energia. A secreção salivar consome glicose e mobiliza o glicogênio para adquirir energia, e este processo pode sofrer influencia de alguns fatores dentre eles o estado diabético e o ritmo circadiano. O diabetes altera todo o metabolismo de carboidratos e diminui o fluxo salivar. Já o ritmo circadiano promove uma alteração fisiológica no fluxo e composição da saliva de acordo com o horário do dia. Desta forma o objetivo deste trabalho foi em um primeiro momento observar o comportamento da concentração de glicogênio em glândulas parótidas e submandibulares de ratos com diferentes idades e condições alimentares em um determinado período do dia. Em um segundo momento observar as alterações que ocorrem na concentração de glicogênio em ratos diabéticos durante o dia. Na primeira fase do estudo foram utilizados ratos saudáveis com 21, 30 e 60 dias de vida, divididos em grupos alimentado e alimentados com restrição. No grupo com restrição de alimento os animais ficaram restritos a alimentação noturna (19 7 horas) desde 2 dias antes do sacrifício. Na segunda fase do estudo, com ratos diabéticos, foram utilizados animais com 60 dias de vida e a indução do diabetes foi realizada através de uma injeção intraperitoneal de estreptozotocina (65 mg/Kg p.c.). 30 dias após a indução os animais foram sacrificados. Em todos os grupos o sacrifício foi realizado nos seguintes horários - 7, 9, 11, 13, 15, 17 e 19 horas. As glândulas submandibulares e parótidas foram removidas imediatamente para posterior análise da concentração de glicogênio. Os dados foram analisados estatisticamente pelos testes ANOVA e o teste de Tukey (p<0.05). Os resultados obtidos com os animais normais mostra uma variação da concentração de glicogênio durante o período analisado nas duas glândulas, sendo mais evidente quando os ratos não foram submetidos a restrição de alimento. Nesta condição a variação da concentração de glicogênio em glândulas parótidas pouco alterou independente da idade. Nos animais diabéticos observamos um acúmulo de glicogênio nas glândulas parótidas e uma diminuição da concentração de glicogênio em submandibulares. Durante o período analisado também houve pouca variação da concentração de glicogênio, assim como nos animais não diabéticos, sendo evidente a menor interferência do ritmo circadiano no estado diabético. Esse estudo nos mostrou que o ritmo circadiano interfere na concentração de glicogênio das glândulas salivares parótidas e submandibulares de ratos durante o período analisado e que a restrição de alimento durante o dia alterou a concentração de glicogênio principalmente nas glândulas parótidas. Observamos também que no estado diabético ocorre um acúmulo do glicogênio em glândulas parótidas e uma diminuição nas glândulas submandibulares. / The secretory process is very important for oral health. The majors salivary glands (parotid, submandibular and sublingual) are the most important for secretion of saliva, for this activity the glands needs energy and a common way obtain is using glucose from the mobilization of glycogen during the fast period. Because of the importance of glycogen in this process, this study aimed to analyze the behavior of glycogen concentration during the day (7 to 19 hours) in parotid, and submandibular glands of rats. In the first moment the study was made with health male rats in different ages (21, 30 and 60 days old), divided in a group with free access to food and other group fed only during the night (19 to 7 hours). The second part of the study was made using diabetic male rats to search for alterations caused by this disease in glycogen concentration. All animals were killed during the day in different hours (7, 9, 11, 13, 15, 17,19 hours), their glands were removed and clamped between aluminium plates pre-cooled in dry ice. The frozen glands were then stored at -80oC until analysis of glycogen concentration. The statistical analyses was made using ANOVA test and Tukey (p<0,5). In the group of health rats we observed a variation of the glycogen concentration during the period analyzed in both glands, but it became more evident when the animals had free access to food. When they were fed during the night the variation of the glycogen concentration in parotid glands were not so evident. The results with diabetics rats showed a higher accumulation of glycogen in parotid glands and a lower concentration of glycogen in submandibular glands. In this period we could not see the variation of glycogen that happen in health rats. This study showed that circadian rhythm modify the concentration of glycogen in parotid and submandibular glands in health rats and the restriction of food made alterations in glycogen concentration of parotid glands. In diabetic rats was possible to see a higher concentration of glycogen in parotid and lower concentration in submandibular gland compared with health rats.

Submitted by isabela.moljf@hotmail.com (isabela.moljf@hotmail.com) on 2017-05-15T14:42:15Z No. of bitstreams: 1 andredeassislauria.pdf: 4832173 bytes, checksum: 60c5b67c92e15253824a647cbc33e9ce (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-05-17T16:00:20Z (GMT) No. of bitstreams: 1 andredeassislauria.pdf: 4832173 bytes, checksum: 60c5b67c92e15253824a647cbc33e9ce (MD5) / Made available in DSpace on 2017-05-17T16:00:20Z (GMT). No. of bitstreams: 1 andredeassislauria.pdf: 4832173 bytes, checksum: 60c5b67c92e15253824a647cbc33e9ce (MD5) Previous issue date: 2010-03-12 / A FCrep é utilizada para a prescrição de exercícios aeróbicos, controle de cargas de treinamento, além de ser utilizado como um indicador dos fatores de risco. A medida da FCrep deve ser coletada na parte da manhã ao acordar e nem sempre é possível se fazer uma medida adequada por problemas metodológicos. A FCrep também muda de acordo com a hora do dia, com seu padrão já estabelecido em estudos anteriores. Sabendo da dificuldade de mensuração e da influência de fatores exógenos ao longo do dia, os objetivos do estudo foram de verificar: 1) A fidedignidade intra e interdias da FCrep; 2) A ritmicidade da FCrep em diferentes horas do dia em indivíduos com diferentes padrões de atividade física; 3) Predizer a FCrep através de equação de regressão. A amostra foi constituída de 107 sujeitos, 69 homens e 38 mulheres, escolhidos intencionalmente por conveniência. Para o estudo 1, 17 indivíduos foram avaliados e submetidos a 3 medições da FCrep, duas no laboratório (Lab 1 e 3 min depois Lab 2), e outra em casa (Casa). Para o estudo 2, 90 sujeitos, foram avaliados pelo nível de atividade física, identificado pelo questionário de atividade física habitual, e separados em 2 grupos, A (mais ativo) e B (menos ativo) respectivamente. Os sujeitos se auto-avaliaram em diferentes horários do dia: 6, 9, 12, 15, 18, 21 e 24 h. Para o estudo 3, utilizando os dados do estudo 2, foi adotado o valor de 6 h como sendo referencia, a partir daí os valores foram normalizados e apresentados mediante as médias dos aumentos % por hora. Foi feito um ajuste por equação de segundo grau para predizer a FCrep de 6 h. Foi realizada ANOVA, teste “t” Student e correlação de Pearson (p<0,05). No estudo 1, os valores registrados pelo sujeito foram: Lab 1: 67±7,1 bpm; Lab 2: 66±6,6 bpm e Casa: 68±6,8 bpm e pelo avaliador: Lab 1: 67±7,0 bpm; Lab 2: 66±6,8 bpm. Não houve diferenças significativas entre as coletas realizadas. Sobre a ritmicidade da FCrep investigada no estudo 2, não houve diferença entre o grupo mais ativo e menos ativo. Os valores de FCrep em diferentes horas do dia foram de 62 ± 8,6 (6h), 66 ± 9,9 (9h), 67 ± 10,1 (12h), 68 ± 9,2 (15h), 69 ± 9,5 (18h), 66 ± 8,9 (21h) e 64 ± 10,1 (24h). O estudo 3 mostrou ser possível predizer a FCrep com valores de R entre 0,70 e 0,83 e erro padrão de estimativa entre 4,8 e 6,2 bpm, dependendo do horário coletado. Conclui-se que indivíduos têm condições de se auto-avaliarem, independente do horário e do local da avaliação. A FCrep não é alterada quanto ao sua ritmicidade em indivíduos com diferentes padrões de atividade física. É possível predizer a FCrep através de uma equação simples. / The HRres is used for the prescription of aerobic exercise, control of training loads, and is used as an indicator of risk factors. The measure of HRres should be collected in the morning to wake up and is not always possible to make an appropriate assessment due to methodological problems. The HRres also changes according to time of day, with its pattern already established in previous studies. Knowing the difficulty of measurement and the influence of exogenous factors throughout the day, the study objectives were to determine: 1) The reliability of intra-and interday HRres; 2) The rhythmicity of HRres at different times of day when individuals with different patterns of physical activity; 3) Predicting the HRres through regression equation. The sample consisted of 107 subjects, 69 men and 38 women, intentionally chosen for convenience. For the study 1, 17 individuals were evaluated and subjected to 3 measurements HRres, two in the laboratory (Lab 1 and 3 min after Lab 2), and another at home (House). For study 2, 90 subjects were evaluated by the level of physical activity, identified by the questionnaire of habitual physical activity in which the sample was divided into 2 groups, A (most active) and B (less active) respectively, and the subjects were self-evaluated at different times of the day: 6, 9, 12, 15, 18, 21 e 24 h. For the study 3, using data from study 2, we adopted the value of 6 h as reference, thereafter the values were normalized and presented by the %mean increase per hour. Was made a quadratic fit to predict HRres 6 h. ANOVA was performed, "t" Student test and Pearson correlation (p <0.05). In study 1, the values recorded by the subject were: Lab 1: 67 ± 7,1 bpm; Lab 2: 66 ± 6,6 bpm and House: 68 ± 6,8 bpm and the evaluator: Lab 1: 67 ± 7,0 bpm; Lab 2: 66 ± 6,8 bpm. There were no significant differences between the collections. On the rhythmicity of HRres investigated in Study 2, there was no difference between the group more active and less active. Values HRres at different times of day were 62 ± 8,6 (6h), 66 ± 9,9 (9 am), 67 ± 10,1 (12h), 68 ± 9,2 (15h), 69 ± 9,5 (18h), 66 ± 8,9 (21h) and 64 ± 10,1 (24). The study 3 was conducted based on the data of the study 2, in which it was possible to predict the HRres with r values between 0.70 and 0.83 and a standard error of estimate between 4,8 and 6,2 bpm depending on the time of the collection. It follows that individuals are able to self-evaluation, independent of time and place of the evaluation. The HRres is not changed as to its rhythm in individuals with different patterns of physical activity. We can predict the HRres through a simple equation.

Orientador: Milva Maria Figueiredo De Martino / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T23:21:59Z (GMT). No. of bitstreams: 1 Carmona_LucianeRuiz_D.pdf: 4020231 bytes, checksum: 3a495b39346f1f0920874ed134289dec (MD5) Previous issue date: 2011 / Resumo: Introdução: Devido à crescente industrialização da sociedade, torna-se cada vez mais comum o trabalho em turnos, bem como o desenvolvimento do trabalho noturno, porém com pronunciado efeito negativo no sono, desempenho e saúde. Objetivo: Investigar os padrões do ciclo vigília-sono e a ritmicidade circadiana da temperatura corporal periférica, através das medidas tomadas no punho, do estudante de enfermagem do período diurno que trabalha no turno noturno. Método: Estudo longitudinal descritivo, com enfoque quantitativo, em que participaram 27 sujeitos adultos, auxiliares e técnicos de enfermagem que trabalhavam no turno noturno, e que eram alunos do curso de graduação em Enfermagem de uma faculdade particular do interior paulista, no período diurno. Foram utilizados os seguintes instrumentos: Ficha de Identificação, Questionário de Indivíduos Matutinos e Vespertinos (HO), Questionário de Sonolência de Epworth, Diário de Sono, durante 32 dias, divididos em período letivo e férias, e um termistor (Thermochron iButton®) no punho da mão não dominante, para verificação de temperatura do punho a cada 30 minutos. Resultados: Quanto ao ajuste dos dados de temperatura do punho a uma curva cosseno, com um período de 24 horas, foi verificada ritmicidade significante em 35,3% dos sujeitos no período letivo e em 93,7% dos sujeitos no período de férias, além da existência de ritmos diferentes de 24 horas, como de 12 e 16 horas. A média da amplitude rítmica da temperatura do punho foi menor no período letivo quando comparado ao período de férias. Houve diferença estatisticamente significativa no horário em que ocorreu a acrofase, quando comparado o período letivo sem trabalho e com trabalho (p<0,0001), período de férias sem trabalho e férias com trabalho (p<0,0001). Quanto ao tempo de sono, no período de férias, foi maior quando comparado ao letivo, assim como nos dias sem trabalho e nos dias em que não dormiram imediatamente após o trabalho noturno. Verificou-se diferença significativa quando comparado o tempo de sono no período de férias sem trabalho (8:34h) e período letivo sem trabalho (7:24h), com p<0,0001, e ainda nas férias com trabalho (5:11h) e letivo com trabalho (4:19h), com p=0,0496. Quanto à Meia Fase do Sono (MFS), houve diferença estatisticamente significativa entre os períodos letivo e férias com e sem trabalho. Os sujeitos apresentaram escores de sonolência entre 7,2 e 15,9, com média de 11,4, caracterizando prevalência de sonolência diurna excessiva. Conclusão: Verificou-se redução das horas de sono do estudante trabalhador noturno, devido a necessidade de frequentar as aulas no período matutino. Observou-se a presença de ritmos diferentes de 24 horas, especialmente durante o período letivo, e o deslocamento de fase da temperatura do punho, de acordo com a jornada de trabalho/estudo, com oposição de fase nos dias com trabalho quando comparado aos dias sem trabalho noturno. A maior potência espectral foi verificada no ritmo de 24 horas, tanto no período letivo como durante as férias, confirmando a hipótese de que a região do punho apresenta expressão rítmica bem definida e robusta. Os achados reforçam a ideia de que o estudo favorece o estabelecimento de rotina, porém pouco influencia no deslocamento da temperatura corporal, que demonstrou ser fortemente influenciada pelo trabalho noturno. Semelhantemente à acrofase, a meia fase do sono apresentou grande diversidade nos horários de ocorrência, porém com relação de fase mantida entre os ritmos, nos diferentes momentos do estudo / Abstract: Introduction: Due to the increasing industrialization of society, the work in shifts is becoming increasingly common, as well as the development of night work, although with a pronounced negative effect on the workers sleep, performance and health. Objective: to investigate the patterns of sleep-wake cycle and the circadian rhythmicity of peripheral body temperature, through measures taken at the wrist of nursing students who studies during the day and works on the night shift. Methods: longitudinal descriptive study, with a quantitative approach, involving 27 adult subjects, nursing assistants and technicians who worked in the night shift and were students of undergraduate nursing of a private college in São Paulo State, during the daytime. The following instruments were used: Identification Form, Morningness Eveningness Questionnaire of Horne and Östberg, Sleepiness Questionnaire Epworth, Sleep Diary, for 32 days, divided into school term and school vacations, and a thermistor (Thermochron iButton) on the non-dominant hand wrist to check the temperature of the wrist every 30 minutes. Results: The adjustment of the temperature data of the wrist to a cosine curve, within a 24-hour period, a significant rhythmicity was verified in 35.3% of subjects in the school term and 93.7% of subjects in the vacation period, apart from the existence of different rhythms of the 24 hours such as 12 and 16 hours. The average amplitude of the wrist temperature rhythm was lower in the scholl term when compared to the vacation period. There was a statistically significant difference in the time that the acrophase occurred, when comparing the school term on the days-off and on working days (p<0.0001), school vacation on the days-off and working days (p<0.0001). The sleep time during the school vacation was higher when compared to the school term, as well as on the days off and on the days when the subjects didn't sleep immediately after work. There was a significant difference when comparing the sleep time on the vacation period and days off (8:34) and school term and days off (7:24), p<0.0001, and also on vacation on working days (5:11) and school term on working days (4:19), p=0.0496. The Middle Phase of Sleep (MPS) there was a statistically significant difference between the school and vacation periods on working days and days off. The subjects presented EDS scores between 7.2 and 15.9, averaging 11.4, characterizing the prevalence of excessive daytime sleepiness. Conclusion: It was verified an intensification of the 14 reduction of hours of sleep of the night working student, because of the need to attend classes in the morning. The presence of rhythms different than 24 hours, was observed especially during the school term, and the phase transfer of the wrist temperature, according to the period of work/study, with phase opposition on working days when compared to days off. The greatest spectral power was observed in the 24-hour rhythm, either during school term or vacation, confirming the hypothesis that the region of the wrist shows a well-defined and robust rhythmic expression. The findings reinforce the idea that the study favors the establishment of routine, but has little influence in displacing the body temperature, wich proved to be strongly influenced by the night shift work. Similar to the acrophase, the MPS showed great diversity in times of occurrence, but with a phase relation maintained between the rhythms on the different times of study / Doutorado / Enfermagem e Trabalho / Doutor em Enfermagem

Abstract Light acts as the most important regulating and entraining factor of the mammalian circadian rhythm. This rhythm has evolved to set phases, in which different physiological and behavioral events occur at the right time of the day to synchronize the organism. The mechanism of light transduction via eyes to the brain and its effects on circadian rhythmicity is well known. Yet, it has also been shown that light is able to penetrate the skull bone directly, but it is still unknown, whether transcranial light is able to affect molecules regulating circadian rhythmicity. Monoamines and especially opsins have been shown to act as important regulators in circadian rhythmicity. Both group of molecules can mediate the effects of light on regulation and entrainment. In this thesis, mice and hamsters have been illuminated transcranially and the expression of three different opsins and the concentrations of several monoamines have been measured. The animals were illuminated under anesthesia either just after the onset of the light period or just after the beginning of the dark period. The opsin expression in rodent brain were measured by western blot and the monoamine concentrations from mouse brain, plasma and adrenal gland were measured by HPLC. It was observed that both opsin expression and monoamine concentrations can be influenced by transcranial illumination. The effect varied depending on the studied molecule, tissue and time of illumination. The findings of this study demonstrate that opsins, which are considered to be the most important molecules regulating circadian rhythmicity, can be directly and specifically affected not only via the eyes but also by light illuminated through the skull. Furthermore, monoamine production can be altered in both the central nervous system and the peripheral tissues by transcranial illumination. This thesis demonstrates an alternate pathway for circadian entrainment and regulation by light involving specific molecular mediators such as opsins and monoamines. / Tiivistelmä Valo on tärkein yksittäinen tekijä nisäkkäiden vuorokausirytmiikassa. Tämä rytmi on kehittynyt ajoittamaan fysiologiset ja käyttäytymiseen perustuvat ilmiöt tapahtumaan oikeaan aikaan vuorokaudesta. Valosignaalin välittyminen silmien kautta aivoihin ja sen vaikutukset vuorokausirytmiikkaan ovat hyvin tunnetut ja paljon tutkitut, mutta vielä on epäselvää, pystyykö kallon läpi annettava valo samaan, vaikka valon on osoitettu pystyvän läpäisemään nisäkkäiden kallon. Monoamiinit ja opsiinit ovat molekyylejä, jotka ovat tärkeässä roolissa vuorokausirytmiikan säätelyssä, ja molempien ilmeneminen on riippuvainen valon määrästä. Tässä väitöskirjassa valotettiin hiirien ja hamstereiden aivoja korvan kautta annettavalla valolla ja mitattiin kolmen eri opsiinin ekspressiota sekä monoamiinien määrää. Eläimiä valotettiin nukutuksessa joko valojakson alussa aamulla tai valojakson päätyttyä illalla. Opsiinien ekspressio aivoissa mitattiin western blot -menetelmällä ja monoamiinien HPLC-menetelmällä. Tuloksista huomattiin, että sekä opsiinien ekspressioon että monoamiinien pitoisuuksiin voidaan vaikuttaa suoraan kallon läpi annettavalla valolla. Valohoidon vaikutus riippui tutkittavasta molekyylistä, kudoksesta ja valohoidon ajankohdasta. Näiden tulosten avulla pystyttiin osoittamaan, että opsiinien, jotka ovat tärkeimpiä molekyylejä vuorokausirytmiikan säätelyssä, määrää voidaan manipuloida myös kallon läpi annettavan valon vaikutuksesta. Lisäksi kallon läpi annettavalla valolla voidaan vaikuttaa monoamiinien pitoisuuksiin sekä keskushermostossa että muissa kudoksissa. Tämä väitöskirja antaa tärkeää tietoa vuorokausirytmiikkaa säätelevistä molekyyleistä ja osoittaa, että niihin pystytään vaikuttamaan myös muuten kuin silmien kautta annettavalla valolla.

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På jordklotets nordliga breddgrader påverkas människor av mörka säsonger med liten tillgång till dagsljus, med fysiska påföljder så som sömnproblem och energibrist. Problemet kan minskas med ljuskällor som kan imitera soldygnet men dessa produkter lämnar föga åt fantasin. Denna studie har undersökt möjligheten att genom produktdesign imitera nordbors perception av dagsljus inomhus för att erbjuda användaren en emotionell upplevelse. Genom användarcentrerad design och kvalitativa metoder sammanställdes empiriska data för att skapa en samlad bild av nordbors perception av dagsljus inomhus. Studiens teoretiska ramverk berörde även ljusdesign och framför allt human-centric lighting samt ludisk design. Studien visar att det är av stor vikt att erbjuda individanpassning i denna typ av produkt för att förse användaren med en emotionell upplevelse. Slutkonceptet är en takarmatur för hemmet som erbjuder användaren lekfull design och interaktion, möjlighet att återskapa dygnsrytm samt en imitation av den egna perceptionen av dagsljus. / On the northern latitudes of the globe, people are affected by dark seasons with little access to daylight, with physical effects such as problems sleeping and loss of energy. The problems can be reduced with light sources that can imitate the sun, but these products leave little to the imagination.This study has investigated the possibility of imitating northerners’ perception of daylight indoors through product design to offer the user an emotional experience. Through user-centered design and qualitative methods, empirical data were compiled to create a unified image of northerners’ perception of daylight indoors. The study's theoretical framework also included lighting design, above all, human-centric lighting and ludic design.The study shows that it is of great importance to offer individual customization in this kind of product in order to provide the user with an emotional experience. The final concept is a light fixture for the home that offers the user playful design and interaction, the opportunity to recreate the circadian rhythm and an imitation of one's own perception of daylight.

It is well known that 24-hour day-night (light-dark) cycles can entrain the circadian rhythms of most species possessing circadian clocks. However, much less is understood about how other environmental cycles operate as entraining signals (zeitgebers) to synchronize (entrain) the internal clock with the outside world. Potential non-photic zeitgebers include daily cycles of temperature, food availability, and social signals. This project’s goal is to evaluate the efficacy of temperature cycles of varying amplitudes, ranging from 1°C to 10°C, as potential zeitgebers for two different circadian rhythms, eclosion and locomotor activity, in the flesh fly (Sarcophaga crassipalpis). Both rhythms were monitored in individual flies, using infrared motion detectors, under precisely controlled 24-hour temperature cycles (12 hours of high temperature [thermophase] alternating with 12 hours of low temperature [cryophase]) in constant darkness. Our results show clear entrainment of eclosion, a once-in-a-lifetime event, and locomotor activity, reflecting daily sleep-wake rhythms, in response to temperature cycles at amplitudes of 2.5, 5, and 10o C. At 1o C amplitudes, the evidence indicates a partial effect of temperature on the phasing of the two behaviors but not true entrainment (phase regulation), suggesting that 1o C amplitudes may be near the threshold for detection by the entrainment pathways communicating with the circadian clock. Interestingly, although both light and temperature cycles entrain the locomotor activity rhythm, the entrainment profiles are remarkably different, thereby suggesting that light and temperature cycles activate different behavioral programs. Finally, flies placed under different constant temperatures have endogenous circadian periods of locomotor activity that are remarkably similar, indicating a high level of temperature compensation. Our results provide conclusive evidence that temperature is a strong circadian zeitgeber in flesh flies, thereby expanding the known repertoire of environmental cues these organisms use to sync their internal clock with the world around them. These findings also set the stage for future experiments designed to explore the interactions between light and temperature entrainment mechanisms – these zeitgeber interactions almost certainly occur in nature but have received little or no attention.

No description available.

An organism’s circadian clock exists as a self-regulating oscillator that can synchronize with its surroundings. This manifests as physiological and behavioral output which can anticipate changes in environment. These rhythms may even persist internally and are known to oscillate at a period (tau) of around 24 hours even in the absence of external cues. In the laboratory, such rhythmic output is known as a free-running period (FRP). Given that circadian rhythms are distributed in a number of taxa as well as their tendency to oscillate along with the solar day, it has been suggested that they result from natural selection. The argument that tone’s clock is adaptive is based on how it is advantageous: the clock instills temporal order among physiological processes as well as enabling one to anticipate external cues. Losing that order in one’s clock has also been associated with a number of metabolic and neurological pathologies. Along with adaptive significance, it has been surmised that an internal clock which synchronizes with one’s surrounding environment is beneficial to an individual. An organism whose free-running period closest matches the rhythmic output of its external environment will exhibit a higher relative fitness as compared to those whose periods deviate from 24 hours. This forms the basis of the ‘circadian resonance hypothesis’. Circadian resonance has been examined in a number of species, from Cyanobacteria to mammals. Collectively, experimental results have supported the rationale that an individual does best when its internal clock resonates with the 24 hour day. The bowl and doily spider, Frontinella communis, not only has its own endogenous rhythm (free-running period), it exhibits an average free-running period of 28.26 hours, deviating from a usual period of ~24 hours. Keeping in mind the circadian resonance hypothesis, an internal clock with such an extreme deviation from the 24 hour day should prove detrimental to one’s overall health. Despite this, Frontinella communis not only has a long clock; among the species, their clocks also appear to be highly variable, FRPs ranging from ~24 to ~33 hours. This study monitored locomotor activity of Frontinella communis to examine whether its free-running period, on average, remained the same throughout its active season (May-September). It was found that average free-running period in F. communis varied significantly over a five-month period. Average FRP appears to peak in June followed by a steady, linear decline as the season continues. A variety of organisms have been shown to exhibit seasonal responses that allow them to cope with environmental change. It is not known whether the change in Frontinella’s FRP is such an advantage or is merely coincidental. Any free running period detected under the alpha level of 0.05 was not ruled significant. Along with the rise and fall of average FRPs, the presence of FRP deemed significant was found to decline as the season ended- 42% of individuals (n= 19) reported as arrhythmic. While age has been found to correlate with circadian desynchrony in other taxa (rats, humans), an association in Frontinella remains to be tested.