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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Insights on the Regulation of the PERIOD 2 Gene in the Cellular Response to DNA Damage

Jiang, Liang 24 May 2019 (has links)
Circadian rhythm is a ~24-h mechanism that keeps our physiology and behavior in synchrony with environmental changes. PERIOD2 (PER2) is a core component of the circadian clock and a candidate tumor suppressor as its knockout expression results in a cancer-prone animal. p53 is an effector in the DNA damage response and regulates downstream effectors by trans-activation. Recent studies in our lab show that PER2 can bind to p53, and regulates the trans-activation function. This project studied the subcellular distribution of PER2 in response to DNA damage, and explored the role of p53 in the regulation of PER2 subcellular distribution. We found that PER2 accumulates in the nucleus in response to DNA damage, and such accumulation is independent of p53. In addition, we analyzed Single Nucleotide Polymorphisms (SNP) of PER2 in the 1000 Genome project to gain insight onto how missense mutations in PER2 lay at the interface of p53:PER2 binding. In a separate project, we also performed bioinformatics analysis on the iron related genes to discuss the circadian regulation of iron genes in the liver. These findings shed light on the regulation of PER2 under genotoxic stress, genetic variations of Per2 in normal human population, and expression of circadian genes under iron controlled diets. / Master of Science / Circadian rhythm is a ~24-h mechanism that keeps the body in synchrony with the environment. Period2 (Per2) is a gene at the core of circadian rhythm in mammals. In this work, we found that PER2 accumulates in the nucleus of cells in response to DNA damage. In addition, we analyzed the genetic variation of PER2 in general human population to gain insight onto how mutations in PER2 affect the risk of cancer that’s associated to circadian disruption. In a separate project, we performed bioinformatics analysis on the genes related to iron metabolism, and showed pattern of circadian regulation of iron genes in the liver. These findings shed light on how circadian rhythm responds to genotoxic stress, and summarized genetic variations of Per2 in normal human population, and the expression of circadian genes under iron-controlled diets.
82

Behavioural circadian rhythms : a novel approach to monitor sheep in extensive systems and study the differences between beef steers for methane emission, feed efficiency and growth / Ritmos circadianos comportamentais : um novo modo de monitorar ovinos em sistemas extensivos e estudar a emissão de metano, eficiência alimentar e crescimento de bovinos de corte

Sarout, Bruna Nunes Marsiglio January 2017 (has links)
As tecnologias baseadas em sensores estão cada vez mais disponíveis e podem ser usadas para coletar informações detalhadas sobre o comportamento animal. Com esta informação é possível avaliar o ritmo circadiano de variáveis comportamentais e monitorar sua resposta. A identificação de variações na resposta deste ritmo tem o potencial de detectar problemas de saúde e questões de bem-estar animal. O objetivo deste trabalho foi estudar os ritmos circadianos comportamentais como uma nova abordagem para monitorar ovelhas em sistemas extensivos e estudar a emissão de metano, eficiência alimentar e crescimento de novilhos de corte. Este trabalho foi composto por dois experimentos (ovinos e bovinos). Foram utilizados cochos automatizados e sensores de atividade baseados em acelerômetro para coletar informações detalhadas do comportamento ingestivo (bovinos) e do comportamento de atividade (ovinos e bovinos), juntamente com as características de desempenho animal. Estes dados foram utilizados para calcular a percentagem de comportamento cíclico harmônico/sincronizado a cada período de 24 h. Essa porcentagem é chamada de grau de acoplamento funcional (DFC) e é calculada com uso de um período móvel de sete dias. No experimento com ovinos, um total de 29 ovelhas Scottish Blackface foram monitoradas por quatro semanas em cada estação do ano, em sistema extensivo nas terras altas da Escócia. Dados meteorológicos foram coletados diariamente. Modelos estatísticos de regressão com efeito aleatório foram utilizados para avaliar a variação da resposta entre indivíduos. Houve uma forte dinâmica criada pelas estações do ano e pelo ciclo produtivo/fisiológico das ovelhas. Durante a primavera e o verão, o desvio padrão do DFC foi um melhor estimador do ganho de peso quando comparado ao índice de moção. A combinação da análise do DFC e o agrupamento de indivíduos com base em sua resposta às variáveis ambientais oferece potencial para obter informações relevantes para o manejo do rebanho. O experimento de bovinos foi conduzido com duas dietas contrastantes (volumoso: concentrado 8:92 e 50:50) e duas raças (40 mestiços Charolês e 40 Luing). Os padrões diurnos de ingestão e atividade foram altamente sincronizados. O ritmo circadiano da atividade foi importante para explicar as diferentes emissões de metano entre indivíduos, independente da raça ou dieta, e também teve ligação com a eficiência alimentar e o crescimento dos novilhos. Este trabalho mostra a importância dos ritmos circadianos comportamentais e como essas abordagens podem melhorar a qualidade e o significado dos dados provenientes de sensores automatizados. / Sensor-based technologies are becoming increasingly available and can be used to gather detailed information about animal behaviour. With this information it is possible to assess animal behavioural circadian rhythm and monitor its response. Identifying breakdowns of this rhythm has the potential to detect health problems and animal welfare issues. The aim of this work was to study the behavioural circadian rhythms as a novel approach to monitor sheep in extensive systems and to study the differences between beef steers production traits, in methane emission, feed efficiency and growth. This work consisted of two experiments, one dealing with sheep in an extensive system and the other with housed beef steers. Automated feed intake equipment and accelerometer-based activity sensors were used to collect detailed information on feed intake (for cattle) and activity behaviour (for sheep and cattle), alongside animal performance characteristics. These data were used to calculate the percentage of cyclic behaviour that is harmonic/synchronized to each 24 h period as Degree of Functional Coupling (DFC) shown within rolling seven day periods. In the sheep experiment, in total twenty-nine Scottish Blackface ewes were monitored for four consecutive weeks in each season across a full year, in an extensive system on Scottish upland pastures. Weather data were collected daily. Random regression statistical models were used to assess between-individual variation in response to the weather. There was a strong dynamic created by the seasons and by the production and physiological cycle in sheep in these high latitude systems. Over the spring and summer period, the variation in the response of DFC was a better estimator of BWG (Body Weight Gain) than the use of a simple motion index. The combination of circadian rhythm analysis and the clustering of individuals into groups based around their regression response to environmental variables provides considerable potential to glean information relevant for group and individual animal management. The cattle experiment was conducted with two contrasting diets (concentrate-based and mixed diet) and two breeds (40 crossbred Charolais and 40 purebred Luing). The diurnal patterns of feeding and activity behaviours were strong and highly synchronised. Activity rhythmicity was well suited to show up differences between individual methane emissions independent of breed or diet, and it was also well related to important production traits as feed efficiency and growth of beef steers. This work shows the importance of the behavioural circadian rhythms and that these approaches may enhance the quality and meaningfulness of data coming from automated sensors.
83

Behavioural circadian rhythms : a novel approach to monitor sheep in extensive systems and study the differences between beef steers for methane emission, feed efficiency and growth / Ritmos circadianos comportamentais : um novo modo de monitorar ovinos em sistemas extensivos e estudar a emissão de metano, eficiência alimentar e crescimento de bovinos de corte

Sarout, Bruna Nunes Marsiglio January 2017 (has links)
As tecnologias baseadas em sensores estão cada vez mais disponíveis e podem ser usadas para coletar informações detalhadas sobre o comportamento animal. Com esta informação é possível avaliar o ritmo circadiano de variáveis comportamentais e monitorar sua resposta. A identificação de variações na resposta deste ritmo tem o potencial de detectar problemas de saúde e questões de bem-estar animal. O objetivo deste trabalho foi estudar os ritmos circadianos comportamentais como uma nova abordagem para monitorar ovelhas em sistemas extensivos e estudar a emissão de metano, eficiência alimentar e crescimento de novilhos de corte. Este trabalho foi composto por dois experimentos (ovinos e bovinos). Foram utilizados cochos automatizados e sensores de atividade baseados em acelerômetro para coletar informações detalhadas do comportamento ingestivo (bovinos) e do comportamento de atividade (ovinos e bovinos), juntamente com as características de desempenho animal. Estes dados foram utilizados para calcular a percentagem de comportamento cíclico harmônico/sincronizado a cada período de 24 h. Essa porcentagem é chamada de grau de acoplamento funcional (DFC) e é calculada com uso de um período móvel de sete dias. No experimento com ovinos, um total de 29 ovelhas Scottish Blackface foram monitoradas por quatro semanas em cada estação do ano, em sistema extensivo nas terras altas da Escócia. Dados meteorológicos foram coletados diariamente. Modelos estatísticos de regressão com efeito aleatório foram utilizados para avaliar a variação da resposta entre indivíduos. Houve uma forte dinâmica criada pelas estações do ano e pelo ciclo produtivo/fisiológico das ovelhas. Durante a primavera e o verão, o desvio padrão do DFC foi um melhor estimador do ganho de peso quando comparado ao índice de moção. A combinação da análise do DFC e o agrupamento de indivíduos com base em sua resposta às variáveis ambientais oferece potencial para obter informações relevantes para o manejo do rebanho. O experimento de bovinos foi conduzido com duas dietas contrastantes (volumoso: concentrado 8:92 e 50:50) e duas raças (40 mestiços Charolês e 40 Luing). Os padrões diurnos de ingestão e atividade foram altamente sincronizados. O ritmo circadiano da atividade foi importante para explicar as diferentes emissões de metano entre indivíduos, independente da raça ou dieta, e também teve ligação com a eficiência alimentar e o crescimento dos novilhos. Este trabalho mostra a importância dos ritmos circadianos comportamentais e como essas abordagens podem melhorar a qualidade e o significado dos dados provenientes de sensores automatizados. / Sensor-based technologies are becoming increasingly available and can be used to gather detailed information about animal behaviour. With this information it is possible to assess animal behavioural circadian rhythm and monitor its response. Identifying breakdowns of this rhythm has the potential to detect health problems and animal welfare issues. The aim of this work was to study the behavioural circadian rhythms as a novel approach to monitor sheep in extensive systems and to study the differences between beef steers production traits, in methane emission, feed efficiency and growth. This work consisted of two experiments, one dealing with sheep in an extensive system and the other with housed beef steers. Automated feed intake equipment and accelerometer-based activity sensors were used to collect detailed information on feed intake (for cattle) and activity behaviour (for sheep and cattle), alongside animal performance characteristics. These data were used to calculate the percentage of cyclic behaviour that is harmonic/synchronized to each 24 h period as Degree of Functional Coupling (DFC) shown within rolling seven day periods. In the sheep experiment, in total twenty-nine Scottish Blackface ewes were monitored for four consecutive weeks in each season across a full year, in an extensive system on Scottish upland pastures. Weather data were collected daily. Random regression statistical models were used to assess between-individual variation in response to the weather. There was a strong dynamic created by the seasons and by the production and physiological cycle in sheep in these high latitude systems. Over the spring and summer period, the variation in the response of DFC was a better estimator of BWG (Body Weight Gain) than the use of a simple motion index. The combination of circadian rhythm analysis and the clustering of individuals into groups based around their regression response to environmental variables provides considerable potential to glean information relevant for group and individual animal management. The cattle experiment was conducted with two contrasting diets (concentrate-based and mixed diet) and two breeds (40 crossbred Charolais and 40 purebred Luing). The diurnal patterns of feeding and activity behaviours were strong and highly synchronised. Activity rhythmicity was well suited to show up differences between individual methane emissions independent of breed or diet, and it was also well related to important production traits as feed efficiency and growth of beef steers. This work shows the importance of the behavioural circadian rhythms and that these approaches may enhance the quality and meaningfulness of data coming from automated sensors.
84

Behavioural circadian rhythms : a novel approach to monitor sheep in extensive systems and study the differences between beef steers for methane emission, feed efficiency and growth / Ritmos circadianos comportamentais : um novo modo de monitorar ovinos em sistemas extensivos e estudar a emissão de metano, eficiência alimentar e crescimento de bovinos de corte

Sarout, Bruna Nunes Marsiglio January 2017 (has links)
As tecnologias baseadas em sensores estão cada vez mais disponíveis e podem ser usadas para coletar informações detalhadas sobre o comportamento animal. Com esta informação é possível avaliar o ritmo circadiano de variáveis comportamentais e monitorar sua resposta. A identificação de variações na resposta deste ritmo tem o potencial de detectar problemas de saúde e questões de bem-estar animal. O objetivo deste trabalho foi estudar os ritmos circadianos comportamentais como uma nova abordagem para monitorar ovelhas em sistemas extensivos e estudar a emissão de metano, eficiência alimentar e crescimento de novilhos de corte. Este trabalho foi composto por dois experimentos (ovinos e bovinos). Foram utilizados cochos automatizados e sensores de atividade baseados em acelerômetro para coletar informações detalhadas do comportamento ingestivo (bovinos) e do comportamento de atividade (ovinos e bovinos), juntamente com as características de desempenho animal. Estes dados foram utilizados para calcular a percentagem de comportamento cíclico harmônico/sincronizado a cada período de 24 h. Essa porcentagem é chamada de grau de acoplamento funcional (DFC) e é calculada com uso de um período móvel de sete dias. No experimento com ovinos, um total de 29 ovelhas Scottish Blackface foram monitoradas por quatro semanas em cada estação do ano, em sistema extensivo nas terras altas da Escócia. Dados meteorológicos foram coletados diariamente. Modelos estatísticos de regressão com efeito aleatório foram utilizados para avaliar a variação da resposta entre indivíduos. Houve uma forte dinâmica criada pelas estações do ano e pelo ciclo produtivo/fisiológico das ovelhas. Durante a primavera e o verão, o desvio padrão do DFC foi um melhor estimador do ganho de peso quando comparado ao índice de moção. A combinação da análise do DFC e o agrupamento de indivíduos com base em sua resposta às variáveis ambientais oferece potencial para obter informações relevantes para o manejo do rebanho. O experimento de bovinos foi conduzido com duas dietas contrastantes (volumoso: concentrado 8:92 e 50:50) e duas raças (40 mestiços Charolês e 40 Luing). Os padrões diurnos de ingestão e atividade foram altamente sincronizados. O ritmo circadiano da atividade foi importante para explicar as diferentes emissões de metano entre indivíduos, independente da raça ou dieta, e também teve ligação com a eficiência alimentar e o crescimento dos novilhos. Este trabalho mostra a importância dos ritmos circadianos comportamentais e como essas abordagens podem melhorar a qualidade e o significado dos dados provenientes de sensores automatizados. / Sensor-based technologies are becoming increasingly available and can be used to gather detailed information about animal behaviour. With this information it is possible to assess animal behavioural circadian rhythm and monitor its response. Identifying breakdowns of this rhythm has the potential to detect health problems and animal welfare issues. The aim of this work was to study the behavioural circadian rhythms as a novel approach to monitor sheep in extensive systems and to study the differences between beef steers production traits, in methane emission, feed efficiency and growth. This work consisted of two experiments, one dealing with sheep in an extensive system and the other with housed beef steers. Automated feed intake equipment and accelerometer-based activity sensors were used to collect detailed information on feed intake (for cattle) and activity behaviour (for sheep and cattle), alongside animal performance characteristics. These data were used to calculate the percentage of cyclic behaviour that is harmonic/synchronized to each 24 h period as Degree of Functional Coupling (DFC) shown within rolling seven day periods. In the sheep experiment, in total twenty-nine Scottish Blackface ewes were monitored for four consecutive weeks in each season across a full year, in an extensive system on Scottish upland pastures. Weather data were collected daily. Random regression statistical models were used to assess between-individual variation in response to the weather. There was a strong dynamic created by the seasons and by the production and physiological cycle in sheep in these high latitude systems. Over the spring and summer period, the variation in the response of DFC was a better estimator of BWG (Body Weight Gain) than the use of a simple motion index. The combination of circadian rhythm analysis and the clustering of individuals into groups based around their regression response to environmental variables provides considerable potential to glean information relevant for group and individual animal management. The cattle experiment was conducted with two contrasting diets (concentrate-based and mixed diet) and two breeds (40 crossbred Charolais and 40 purebred Luing). The diurnal patterns of feeding and activity behaviours were strong and highly synchronised. Activity rhythmicity was well suited to show up differences between individual methane emissions independent of breed or diet, and it was also well related to important production traits as feed efficiency and growth of beef steers. This work shows the importance of the behavioural circadian rhythms and that these approaches may enhance the quality and meaningfulness of data coming from automated sensors.
85

Melanization and Hemocyte Homeostasis  in the Freshwater Crayfish, Pacifastacus leniusculus

Noonin, Chadanat January 2013 (has links)
Blood cells or hemocytes play important roles in immunity. They are a major source of many immune-related molecules such as antibodies in adaptive immunity of vertebrates and prophenoloxidase (proPO) in invertebrates. In the crayfish Pacifastacus leniusculus, the proPO-system has been reported to be an important component of immune responses against microorganisms. In this study, several mutant strains of Aeromonas hydrophila were used to reveal that LPS (lipopolysaccharide) is an important factor for the pathogenicity of A. hydrophila, strongly inducing the proPO system and melanization. This proPO activating system is a multistep process, which has to be tightly controlled to avoid the harmful side effects of toxic intermediates. Many regulating factors have been reported to fine-tune the proPO-system. In this study, the cleavage of caspase-1-like activity was shown to be a novel negative regulator of PO activity in crayfish. Moreover, the fragments obtained by cleavage of proPO by the proPO-activating enzyme and caspase-1-like protein increased bacterial clearance. Thus, the peptides generated also have important biological functions. In addition to being a source of immune proteins, hemocytes also participate in phagocytosis, encapsulation, and nodulation. An infection normally causes a reduction of hemocyte numbers. Consequently, hemocyte homeostasis is important for maintaining appropriate hemocyte numbers in the circulation of the animal. This study shows that the reactive oxygen species level in the anterior proliferation center of crayfish hematopoietic tissue (HPT), together with cell proliferation, was increased during infection. Pl-β-thymosins were proposed to be involved in hemocyte homeostasis by increasing stem cell migration and thus increasing the circulating hemocyte number. Crayfish hemocyte numbers, as well astakine (Ast1 and Ast2) expression in hemocytes and HPT, were previously shown to be under circadian regulation. Here, we show that Ast1, Ast2, and proPO exhibit rhythmic expression in the crayfish brain similarly to their orthologs, prokineticin 1, prokineticin 2 and tyrosinase, respectively, in the zebrafish brain. Tyrosinase expression was detected in zebrafish brain cells while PO-positive cells were identified as hemocytes that had infiltrated into the crayfish brain. Therefore, this information suggests a close relationship between crayfish hemocytes and the crayfish brain as well as vertebrate neurons.
86

Sleep, circadian and behavioural characterisation of two schizophrenia-relevant transgenic mouse models

Pritchett, David January 2015 (has links)
No description available.
87

Metabolismus železa a mědi u jednobuněčných mořských řas rodu Ostreococcus / Iron and copper metabolism in marine microalgae of the genus Ostreococcus

Pilátová, Jana January 2015 (has links)
The smallest free living eukaryote known as Ostreococcus tauri became along with some related species great experimental models for iron uptake research in marine picoplankton. The ecological context of such topic is very interesting considering the nature of adaptation to iron limitation and its connection to the copper metabolism. Our experiments has simulated iron and copper limiting conditions of the ocean, as a control we used iron and copper repleted cultivation media. The maximum cell counts were two- to threefold higher in iron-repleted medium compared to iron- depleted one. There was the only exception showing no difference in growth - O. lucimarinus coming from open ocean with high irradiance levels and very low iron concentrations, which all together made it the best adapted species. The reinoculation of cell cultures after a week cultivation into to the same iron/copper containing media led to unmasking the copper effect on growth, which was much weaker than encountered with iron (again except of O. lucimarinus). Iron sufficiency positively affects heme b and chlorophyll a and b content with no significant copper dependency. The circadian timing of heme b and chlorophyll a and b content shows the increasing trend during the day followed by decrease at night. This might be caused by...
88

En vårdande ljusmiljö inom intensivvård : Patienters upplevelser och effekter av en cyklisk belysningsintervention

Engwall, Marie January 2017 (has links)
Det övergripande syftet med avhandlingen var att beskriva och undersöka patienters - vårdade inom intensivvård - upplevelser och effekter av en cyklisk belysningsintervention utifrån hälsa, välbefinnande och återhämtning. Metod: En intervention bestående av ett automatiskt styrt belysningssystem var installerat på ett intensivvårdsrum. Belysningsinterventionens mål var att efterlikna dagsljuset i styrka, kvalitet, och lokalisation. Ett ordinarie intensivvårdsrum fungerade som kontrollmiljö. I studie I eftersöktes i en systematisk litteratursammanställning tidigare forskningsresultat rörande cykliska belysningsinterventioner inom intensivvård. Belysningsmiljöerna i intervention- och kontrollmiljön bedömdes i studie I av besökare och i studie II av patienter samt jämfördes och analyserades statistiskt. Ljus och belysningsmätningar utfördes i både forsknings- och kontrollmiljön. I studie II undersöktes patienters upplevelser av den cykliska belysningsmiljön genom kvalitativa intervjuer vilka analyserade med innehållsanalys. I studie II mättes och jämfördes patienters sömn, dygnsrytm samt fysiologiska parametrar och analyserades statistiskt. I studie IV undersöktes och jämfördes patienternas självskattade återhämtning efter sex och tolv månader. Resultat: Cykliska belysningsinterventioner exponerade för vuxna patienter var få. Resultatet visade dock att interventioner med cykliskt ljus inom neonatal intensivvård kunde inverka positivt på förtidigt födda barns hälsa. Den cykliska interventionsmiljön bedömdes som mer trivsam och mätningar av belysningen utförda i interventionsmiljön visade på samstämmighet med europeiska rekommendationer. Belysningsnivåerna i kontrolmiljön var manuellt styrda och mätningarna visade på antingen för låga eller för höga belysningsnivåer under dagtid jämfört med europeiska rekommendationer. Patienterna bedömde den cykliska belysningsmiljön som starkare dagtid och under nattetid bedömdes belysningen i kontrolmiljön som mer varierande. Patienters individuella upplevelser av den cykliska belysningsinterventionen presenterades i fyra kategorier: en dynamisk belysningsmiljö, belysningens påverkan på patientens sömn, ljus/belysnings påverkan på dygnsrytm samt en lugnande belysning. Patienternas dygnsrytm stärktes inte av den cykliska belysningsmiljön under deras sista 24-timmarsperiod. Patienternas självrapporterade återhämtning efter intensivvård var bättre efter 12-månader efter utskrivning hos de som vårdats i interventionsmiljön. Slutsatser: Genom att studera de båda forskningsområdena vårdvetenskap och ljus/belysning tillsammans skapades ny kunskap till vårdvetenskapen. Trots svår sjukdom eller skada kunde patienterna bedöma och reflektera kring belysningsmiljön. Ämnesområdet lämpar sig väl för att undersökas med både kvantitativa och kvalitativa metoder. / Aim: The overall aim of this thesis was to describe and evaluate patients’, who were cared for in the intensive care unit (ICU), experiences and effects concerning a cycled lighting intervention based on health, wellbeing and recovery. Methods: An automatically controlled cycled lighting intervention aimed to mimic natural light levels, quality and position throughout the day was evaluated. An ordinary lit room was used as a control. A multiple-method approach was used. In study I, there were three aspects: a systematic review of the previous research concerning cycled lighting interventions in the intensive care; visitor evaluations of the lighting environments in the intervention and ordinary room; and measurements of illuminance, luminance and irradiance in both conditions. In study II, the patients evaluated the lighting environment in the two rooms. Data were compared and analysed. Furthermore, patients’ experiences regarding the cycled lighting environment were investigated through qualitative interviews, which were subsequently analysed by content analysis. In study III, patients’ sleep, activity and physiological parameters were measured and compared. Study IV consisted of statistical analysis of a questionnaire concerning patients’ self-reported recovery six and 12 months after their ICU treatments. Results: The literature review on cycled lighting interventions in adult ICUs was rare but more common in the neonatal ICU (NICU). Findings showed that cycled lighting interventions improved health in preterm infants, but there were also non-significant results reported. The visitors reported the cycled lighting environment as more pleasant, and based on measurements, the lighting levels were at equivalent levels with European recommendations for hospitals. The lighting levels in the ordinary room were manually controlled and were reported as being either too low or too bright during the daytime. Patients evaluated the cycled lighting environment as brighter in daytime, and this was in coherence with the results from the measurements of illumination. Patients’ individual experiences concerning the cycled lighting environment were reported in four categories: a dynamic lighting environment, the impact of lighting on patients’ sleep, the impact of light/lighting on the circadian rhythm and the degree to which the lighting calmed them. Patients’ circadian rhythms were not further strengthened by the cycled lighting intervention during their final 24-period in the ICU. Twelve months after their ICU treatments, patients cared for in the intervention environment self-reported their recovery as significantly better than those who received treatment in the ordinary room. Conclusions: A multiple methodology was used to explore theresearch field from a wider perspective. Combining knowledge from both the lighting research field and caring science has brought new knowledge to both and especially to the practice of nursing. Despite their severe illnesses or injuries, patients were able to assess their experiences with the lighting environment and reflect on how the lighting was able to support their health. This thesis reports findings that indicate that environmental/lighting interventions may improvepatients’ health. Lighting interventions are harmless, safe, sustainable and, in comparison to technical and medical interventions, considerably cheaper. With this knowledge, we believe all vulnerable patients in the ICU should be surrounded by a lighting environment around the clock to support their health, wellbeing and recovery.
89

Efeitos dos ciclos de iluminação e de marés na ritmicidade da atividade locomotora de Bathygobius soporator (Valenciennes,1837) (Teleostei: Perciformes: Gobiidae) / The effect of the light and tidal cycles on the rhythmicity of the locomotor activity of Bathygobius soporator (Valenciennes 1837) (Teleostei: Perciformes: Gobiidae)

Nomura, Mariene Mitie 04 June 2008 (has links)
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.
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Alteração da concentração de glicogênio durante o dia em glândulas submandibulares e parótidas de ratos / Variation of glycogen concentration in parotid and submandibular gland of rats during the day

Matos, Jonas Alencar de 10 November 2009 (has links)
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.

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