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The association of night-shift work with the development of breast cancer in womenMoukangoe, Phaswane Isaac Justice 10 1900 (has links)
Breast cancer poses a serious public health concern. This case-control study
describes the relationship of night-shift working on the development of breast cancer
in 57 women diagnosed with breast cancer compared to 49 women with other types
of cancer in the Vaal Triangle area (selected through non-probability purposive
sampling from CANSA). The study revealed that women who work night-shift
developed breast cancer 1.24 times more often than women who do not work nightshift
(OR=1.24 [95% CI 0.52 to 2.89]). The odds ratio was further increased in
women who worked rotating-shift (OR=1.44 [95% CI 0.58 to 3.59]). Night-shift work
exposure was not statistically related to the development of breast cancer. It is
recommended that the relationship between night-shift exposure and breast cancer
risk be further explored through cross-sectional and cohort studies, and other breast cancer pathways. / Health Studies / M. A. (Public Health)
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Photopic & scotopic light perceptionBell, Michelle A. January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / This paper discusses photopic and scotopic vision of the human eye and the implications that could result in the design process of the lighting industry. The incorporation of scotopic vision in lighting effects the perceived illumination in all settings; but these affects and benefits are seen more prevalently at night, as this is when scotopic vision is utilized by the eye the most.
The paper will begin with an overview of the eye including discussions of exactly what photopic and scotopic vision are, as well as how the eye works. This will lay a foundation for the paper to help the reader better comprehend and understand the remainder of the content. After the groundwork has been laid, the factors that affect how the eye perceives light will be discussed. These factors include pupil size and color of the light. A discussion of the basis for current lighting industry design and how light levels are measured will follow. Once these topics have been fully explored, there will be a discussion of the changes that could occur in the lighting industry if scotopic vision is taken into account. Increased energy efficiency would result if the scotopic vision is incorporated, resulting from the decrease in needed total lumen output. There have been a few applications that have utilized the effects of the scotopic vision in their design, these cases will be presented. Following the case study discussions, will be a discussion of a survey conducted by myself on the change-out of high pressure sodium (HPS) fixtures to LED fixtures in the downtown Poyntz Avenue area of Manhattan, KS. After all studies have been reviewed, conclusions and correlations among them will be explored. Following this analysis, suggestions will be given to improve the way lighting is designed in the industry.
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Sustainable cooling alternatives for buildingsVorster, Jacobus Adriaan 03 1900 (has links)
Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: The thesis was initiated by a Consulting Engineering Company (KV3) as a research project
to investigate various options in which the efficiency and energy utilisation of conventional
air conditioning systems may be enhanced by using alternative and renewable energy.
Initially, eight options had been identified and through a process of determining the degree of
commercialisation the alternative options were reduced to three. These options, referred to as
the sustainable cooling alternatives, are active mass cooling, night flushing and roof cooling
system.
The roof cooling system comprised a roof-pond, roof-spray, pump and storage tank. The roof
cooling system was mathematically and experimentally modelled. The roof cooling
experiment was performed under a variety of weather conditions with the roof-pond and
storage tank temperatures continuously recorded. The experimentally recorded temperatures
were compared to the temperatures generated by the theoretical simulation calculations for
the same input and weather conditions. Good agreement was found between the
mathematical and experimental model. The largest discrepancy found between the simulated
temperature and the experimental temperature was in the order of 1 ºC.
A one-room building has been assumed to serve as a basis to which the sustainable cooling
alternatives could be applied to for theoretical simulation. The one-room building had four
façade walls and a flat roof slab. Night flushing, active mass cooling and the roof cooling
system were applied to the one-room building such that the room air temperature and space
cooling load could theoretically be simulated. The theoretical simulations were also repeated
for the case where the roof-pond and roof-spray were applied as standalone systems to the
one-room building. The theoretical simulation calculations were performed for typical
summer weather conditions of Stellenbosch, South Africa.
Under base case conditions and for a room thermostat setting of 22 ºC the peak cooling load
of the one-room building was 74.73 W/m². With the application of night flushing between the
hours of 24:00 and 07:00, the room cooling load was reduced by 5.2% by providing
3.9 W/m² of cooling and reducing the peak room temperature by 1.4 ºC. The active mass
cooling system was modelled by supplying water at a constant supply temperature of 15 ºC to
a pipe network embedded in the roof slab of the one-room building. The sea may typically be
considered as a cold water source for buildings situated at the coast. The active mass cooling
system reduced the peak cooling load of the one-room building by 50% by providing
37.2 W/m² of cooling and reducing the peak room temperature by 6.7 ºC.
When the roof-spray and roof-pond systems were applied as standalone systems to the oneroom
building, the peak cooling load of the one-room building could be reduced by 30% and
51% respectively. This is equivalent to 22.3 W/m² of peak cooling by the roof-spray and
38 W/m² of peak cooling by the roof-pond. The roof-spray reduced the peak room
temperature by 3.71 ºC while the roof-pond reduced the peak room temperature by 5.9 ºC.
Applying the roof cooling system to the one-room building produced 46 W/m² of peak
cooling which resulted in a 61.1% reduction in peak cooling load. The roof cooling system
reduced the peak temperature by 8 ºC. By comparing the sustainable cooling alternatives, the roof cooling system showed to be the most effective in reducing the one-room building peak
cooling load. Over a 24 hour period the roof cooling system reduced the net heat entry to the
one-room building by 57.3%.
In a further attempt to reduce the peak cooling load, the sustainable cooling alternatives were
applied in combinations to the one-room building. The combination of night flushing and
roof-spray reduced the peak cooling load by 36% while a combination of night flushing and
active mass cooling reduced the peak cooling load by 55%. Combining night flushing with
the roof-pond also yielded a 55% peak cooling load reduction. The combination of roofpond,
active mass cooling and night flushing provided 51 W/m² of cooling which
corresponded to a 68% reduction in peak cooling load. Utilising the sustainable cooling
alternatives in a combination in the one-room building gave improved results when compared
to the case where the sustainable cooling alternatives were employed as standalone systems.
It is illustrated by means of a sensitivity analysis that the ability of the roof cooling system to
produce cool water is largely influenced by ambient conditions, droplet diameter and roofspray
rate. Under clear sky conditions, an ambient temperature of 15 ºC, relative humidity of
80%, a roof-spray rate of 0.02 kg/sm² and a roof-pond water level of 100mm, water could be
cooled at a rate of 113 W/m². The roof-spray energy contributed to 28 W/m² whilst the night
sky radiation was responsible for 85 W/m² of the water cooling. It must however be noted
that the water of the roof cooling system can never be reduced to a temperature that is lower
than the ambient dew point temperature. / AFRIKAANSE OPSOMMING: Die tesis is geïnisieer deur ‘n Raadgewende Ingenieurs Maatskappy (KV3) as a
navorsingsprojek om verskeie opsies te ondersoek waarmee die effektiwiteit en energie
verbruik van konvensionele lugversorgingstelsels verbeter kan word deur middel van
alternatiewe en hernubare energie. Agt opsies is oorspronglik geïdentifiseer en deur middel
van ‘n proses waarby die graad van kommersialisering van hierdie alternatiewe maniere
bepaal is, kon die opsies verminder word tot drie. Hierdie opsies, ook verwys na as die
volhoubare verkoelingsalternatiewe, sluit in aktiewe massa verkoeling, dakverkoeling en
nagventilasie.
Die dakverkoelingstelsel bestaan uit dakwater, ‘n dakspuit, ‘n pomp en ‘n stoortenk. Die
dakverkoelingstelsel is wiskundig en eksperimenteel gemodelleer. Die dakverkoelingseksperiment
is uitgevoer onder ‘n verskeidenheid van weersomstandighede. Die dakwater
asook die stoortenk se water temperatuur is voortdurend aangeteken. Dieselfde weer- en
insetkondisies is gebruik vir die simulasie berekening en die temperature van die stoortenk se
water en die dakwater is vergelyk met die temperatuurlesings van die eksperimentele werk.
Die temperature van die eksperimentele lesings het goed vergelyk met die temperatuur
simulasie berekeninge. Die grootste verskil tussen die simulasie en eksperimentele
temperatuur was in die orde grootte van 1 ºC.
‘n Een-kamer gebou is aangeneem om as basis te dien waarop die volhoubare
verkoelingsalternatiewe aangewend kon word vir teoretiese simulasie. Die een-kamer gebou
het uit vier buite mure en ‘n horisontale beton dak bestaan. Nag ventilasie, aktiewe massa
verkoeling en die dakverkoelingstelsel is toegepas op die een-kamer gebou en die kamer se
verkoelingslas asook die kamer se lugtempertuur is teoreties gesimuleer. Die teoretiese
simulasies is ook herhaal vir die geval waar die dakwater and dakspuitstelsel apart
aangewend is op die een-kamer gebou. Die teoretiese simulasie berekeninge is uitgevoer vir
tipiese somer weersomstandighede vir Stellenbosch, Suid Afrika.
Onder basisgeval omstandighede, waar die een-kamer gebou gesimuleer is, sonder enige
volhoubare verkoelingsalternatiewe en ‘n termostaat verstelling van 22 ºC, is die piek
verkoelingslas bereken as 74.73 W/m². Met die toepassing van nagventilasie tussen die ure
24:00 en 07:00 was die piekverkoelingslas van die kamer verminder met 5.2% deur 3.9 W/m²
se verkoeling te verskaf en die piekkamer temperatuur te verminder met 1.4 ºC. Aktiewe
massa verkoeling is gesimuleer deur water teen ‘n konstante temperatuur van 15 ºC te verskaf
aan ‘n pypnetwerk, geïnstalleer in the beton dak, van die een-kamer gebou. Geboue geleë aan
die kus kan tipies seewater oorweeg as ‘n bron van koue water. Aktiewe massa verkoeling
het die piekverkoelingslas van die een-kamer gebou verminder met 50% deur 37.2 W/m² se
verkoeling te verskaf en die piekkamer temperatuur te verminder met 6.7 ºC.
Wanneer die dakspuit- en dakwaterstelsel aangewend is op die een-kamer gebou as enkel
staande stelsels, is die piekverkoelingslas verminder met 30% en 51% onderskeidelik. Dit is
ekwivalent aan 22.3 W/m² se verkoeling vir die dakspuitstelsel en 38 W/m² se verkoeling vir
die dakwaterstelsel. Die dakspuitstelsel het die piekkamer temperatuur verminder met 3.71 ºC terwyl die dakwaterstelsel ‘n 5.9 ºC verlaging in piekkamer temperatuur tot gevolg
gehad het.
Die dakverkoelingstelsel het 46 W/m² se piekverkoeling verskaf wat ‘n 61.1% vermindering
in piekverkoelingslas tot gevolg gehad het. Die ooreenstemmende piek temperatuur
vermindering is 8 ºC. Deur die verskeie volhoubare verkoelingsalternatiewe met mekaar te
vergelyk, word getoon dat die dakverkoelingstelsel die mees effektiefste manier is om die
een- kamer se piekverkoelingslas te verminder. Oor ‘n tydperk van 24 uur het die
dakverkoelingstelsel die totale energievloei na die een-kamer gebou met 57.3% verminder.
In ‘n verdere poging om die piekverkoelingslas te verminder, is die volhoubare
verkoelingsalternatiewe toegepas in kombinasies op die een-kamer gebou. Die kombinasie
van nagventilasie met die dakspuitstelsel het die piekverkoelingslas met 36% verminder,
terwyl ‘n kombinasie van nagventilasie en aktiewe massa verkoeling ‘n 55% vermindering in
piekverkoelingslas tot gevolg gehad het. Die kombinasie van dakwater en nagventilasie het
ook ‘n piekverkoelingslas vermindering van 55% teweeggebring. Die kombinasie van
dakwater, aktiewe massa verkoeling en nagventilasie het 51 W/m² se verkoeling veskaf, wat
ooreenstem met ‘n 68% vermindering in piekverkoelingslas. Deur die volhoubare
verkoelingsalternatiewe in kombinasies toe te pas op die een-kamer gebou, kon beter
resultate verkry word toe dit vergelyk is met die geval waar die volhoubare
verkoelingsalternatiewe as enkelstaande stelsels toegepas is.
Dit is geïllustreer deur middel van ‘n sensitiwiteitsanalise dat die vermoë van die
dakverkoelingstelsel om koue water te produseer, beïnvloed word deur buitelug kondisies,
waterdruppel deursnee en dakspuit massa vloeitempo. Onder die oop hemelruimteomstandighede,
‘n buitelug temperatuur van 15 ºC, ‘n relatiewe humiditeit van 80%, ‘n
dakspuit massa vloeitempo van 0.02 kg/sm² en dakwatervlak van 100 mm, kon water verkoel
word teen ‘n tempo van 113 W/m². Die dakspuit gedeelte het 28 W/m² bygedra terwyl die
nagruim radiasie sowat 85 W/m² se verkoeling verskaf het. Daar moet egter kennis geneem
word dat die water temperatuur van die dakverkoelingstelsel nooit verminder kan word tot
onder die buitelug doupunttemperatuur nie.
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Exploring authenticity in performance : a comparative performance analysis of Arnold van Wyk’s Night Music for pianoPinto Ribeiro, Bruno Alfredo 03 1900 (has links)
Thesis (MMus (Music))--University of Stellenbosch, 2009. / Arnold van Wyk was a composer and a pianist. He recorded his largest work for
piano, Night Music (1958), on LP in 1963. Steven de Groote performed Night Music
on 21 July 1984 at the Cheltenham International Festival of Music. This live
performance was broadcast on BBC Radio 3 on 24 September 1984 and a copy of
this broadcast exists in the Arnold van Wyk collection in the J.S. Gericke Library at
Stellenbosch University.
Night Music is a perfect example of Van Wyk’s compositional techniques for
the keyboard. It demands a considerable musical imagination and piano technique
from the performer. The score of Night Music contains many detailed instructions
regarding the different musical parameters and it also encloses unusual terms such
as glacial or lugubre. It shows that the composer is extremely concerned to control
all aspects of the performance and expects great depth of interpretation of the
performer.
Analysing the score of Night Music together with a performance by the
composer enables one to consider two versions of “authenticated text”. The
comparison between Arnold van Wyk’s recording, score and Steven de Groote’s
performance allows the researcher to draw conclusions about score fidelity as a
condition for “authenticity” in performance. Therefore, the primary aim of this
research project is to yield interesting perspectives on notions of authenticity in
performance with regard to these two particular performances of Night Music.
The main body of this thesis consists of four chapters. In Chapter One a
philosophical discussion about authenticity in performance is presented. Chapter
Two focuses on the contextualisation of the work under discussion, including the
reception and a short analysis of Night Music. It is followed by Chapter Three which
compares the pianism of Arnold van Wyk and Steven de Groote. These latter two
chapters form the background of the comparative performance analysis of the
renditions of Night Music by these two performers which are presented in Chapter
Four.
Through the careful comparative analysis of Arnold van Wyk’s and Steven de
Groote’s performances of Night Music it was possible to observe that a composer
can present a version of his work that departs quite radically from the score. As
“authenticity in performance” strives to honour the composer’s intentions as notated
in the score, this discrepancy illustrates the controversial nature of the discourse on
the “authentic” in music.
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Drama and Characterization in Opera Settings of "A Midsummer Nightʼs Dream" by Britten and SiegmeisterAllen, Debra K. (Debra Kaye) 08 1900 (has links)
Although Shakespeare deliberately downplays characterization in his moonlit dream fantasy, both Britten and Siegmeister exploit this dramatic element as the basis of their opera settings of the play. Through the operas, the shallow characters take on new dimensions, creating musical experiences existing quite independently of Shakespeare, while at the same time retaining the atmosphere of a dream-fantasy. Placing emphases upon varying aspects of the play, the two composers create entirely different revelations from the Bard's dream. This paper presents a study of the way in which drama and characterization are treated in the operas, A Midsummer Night's Dream and Night of the Moonspell.
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Psychologická problematika obezity / The Psychological problems of ObesityMašková, Eva January 2013 (has links)
The aim of this thesis is to summarize findings of causes and consequences of obesity, the most common health problem in the world. The theoretical part deals with many key issues of obesity, from definition through the epidemiology, etiology and obesity prevention and treatment. However the main topics of this thesis are the psychological characteristics that are associated with obesity. It includes personality factors of obese people, willpower and self-control and specific psychopathology. The research part of this thesis is mapping the occurrence of a specific psychopathological phenomena focusing on the emotional eating disorder, night eating syndrome and binge eating and symptoms of eating disorder. Applied methods were "Eating Behavior and Emotionality Questionnaire" (JICHEM), "The Eating Disorder Examination Questionnaire 6.0" (EDE - Q) and "The Night Eating Questionnaire" (NEQ). The data of quantitative research was evaluated by standard statistical methods. Keywords: Obesity Psychopathology Eating Disorder Night Eating Syndrome Emocional eating theory
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O \"Livro das Mil e uma Noites\" em Jorge Luis Borges / \"The book of the Thousands Nights and a Night\" in Jorge Luis BorgesMorais, Thais de Godoy 07 June 2013 (has links)
O Livro das mil e uma noites, traduzido por Richard Francis Burton do árabe para o inglês, no séc. XIX, causou um forte impacto na sociedade vitoriana por seu conteúdo erótico. Ao tentar superar as traduções de seus antecessores, Burton reuniu diversos manuscritos e versões impressas, para tentar abarcar o máximo possível de contos, além de acrescentar abundantes notas de rodapé acerca dos costumes da sociedade árabe dos países por onde ele viajou como representante do governo britânico. Sua tradução, constante na biblioteca pessoal de Jorge Luis Borges, inspirou um considerável número de contos desse autor. No âmbito da literatura comparada, as Noites representam um importante hipotexto para a obra borgeana, que reutilizou seus temas, argumentos, imitou seu estilo. Analisar as formas de transcendência textual na obra do autor argentino, através das classificações de Gérard Genette, possibilita uma interpretação das suas relações inter e hipertextual com os contos árabes. Genette procura delimitar com mais precisão termos como paródia, charge, pastiche, sátira, por exemplo, que continuamente são confundidos numa análise mais geral. A obra borgeana tem sido muito genericamente taxada de paródica, mas suas relações intertextuais são muito mais complexas, não apenas com as Mil e uma Noites, mas com todos os autores por ele transformados. Além disso, Borges é o criador de uma nova linguagem, de certos gêneros: como o conto ensaístico e a pseudo-tradução, elencados por Genette, que tem como fonte as Noites. Borges reutiliza o tradicional conto árabe modernizando-o e adaptando-o ao seu próprio estilo e aos tempos modernos, criando formas inteiramente novas de narrativa. / The book of the Thousands Nights and a Night, translated by Richard Francis Burton from Arabic into English, in the century. XIX, caused a strong impact on Victorian society for its erotic content. In trying to overcome the translations of his predecessors, Burton met several manuscripts and printed versions, trying to cover as much of tales, while adding abundant footnotes about the customs of Arab society of the countries through which he traveled as a representative of the British government . His translation, the constant personal library of Jorge Luis Borges, inspired a considerable number of short stories by this author. In the context of comparative literature, the Nights represent an important hypotext to work Borges, who reused their themes, arguments, imitated his style. Analyze textual forms of transcendence in the work of the Argentine author, through the ratings Gérard Genette, provides an interpretation of their relationship with the inter-and hypertextual Arab tales. Genette seeks to define more precisely terms like parody, caricature, pastiche, satire, for example, are continually confounded a more general analysis. Borges\'s work has been very generically labeled as parody, but their intertextual relationships are much more complex, not only with the Thousand and One Nights, but with all the authors he transformed. Moreover, Borges is the creator of a new language, certain genres: the short story as essayistic and pseudo-translation, listed by Genette, whose source the Nights. Borges reuses the traditional Arabic tale modernizing it and adapting it to their own style and modern times, creating entirely new ways of storytelling.
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Efeitos do trabalho noturno nos ritmos circadianos de marcadores do processo inflamatório / Effects of night work on circadian rhythms of markers of inflammationBurgos, Leana Gonçalves Araujo 22 June 2015 (has links)
Introdução: Uma das reconhecidas consequências do trabalho noturno nos trabalhadores é a perda da ordem temporal interna, a qual resulta em alterações fisiopatológicas. Objetivo: O presente estudo teve o objetivo de avaliar os efeitos do turno noturno de traballho na concentração e no ritmo circadiano de citocinas inflamatórias de trabalhadores de linha de produção e operadores de máquinas. Material e Métodos: Estudo transversal realizado em uma empresa do setor de bebidas. Na Etapa 1 foram avaliados em 123 trabalhadores (56 do turno fixo diurno e 67 do turno fixo noturno), dados sociodemográficos, condições de vida e lazer, condições e organização do trabalho, morbidades, sintomas osteomusculares, fadiga, sonolência excessiva e dados antropométricos. Quinze voluntários do turno diurno, 15 do turno noturno em período de trabalho e em momento de férias participaram da Etapa 2. Durante sete dias foram coletados dados do padrão de sono e vigília e em um Dia de Trabalho e um Dia de Folga foram realizadas coletas salivares em intervalos de três horas, durante a vigília, para estimar a concentração de melatonina, IL-1 e IL-6, além de coletados dados de sonolência, fadiga e dor. Também foi realizada coleta de urina para medir 6-sulfatoximelatonina após o episódio principal de sono. Foram verificadas diferenças de médias entre os dados dos grupos obtidos na Etapa 1, assim como análises de Odds Ratio. A ANOVA Nested foi utilizada na Etapa 2 para comparar os grupos (Diurno, Noturno e Noturno-Férias), seguida do teste de contraste de Dunnet. A Etapa 3 comparou a curva das citocinas IL-1, IL-6 e TNF- na saliva e no sangue em 7 indivíduos saudáveis em laboratório. O método do Cosinor individual e populacional foi aplicado para verificar ritmicidade circadiana. Resultados: Os resultados revelaram que os trabalhadores noturnos tinham menor amplitude do ritmo da melatonina salivar que os diurnos. Embora a concentração de 6-sulfatoximelatonina também tenha sido menor entre os trabalhadores noturnos comparados com os diurnos, sua concentração foi mais elevada durante as férias. Nas férias se observou um aumento da duração do sono, apesar de não ter sido verificada nenhuma diferença entre os parâmetros do sono principal e do cochilo entre os trabalhadores dos turnos diurnos e noturno no período de trabalho. No entanto, a acrofase da citocina IL-6 ocorreu em horário similar nos três grupos, ainda que os trabalhadores noturnos tenham apresentado maior concentração dessa citocina. A IL-1 apresentou ritmicidade apenas para o grupo diurno. Não houve diferença na prevalência de doenças entre os Grupos Diurno e Noturno. Os dados com os indivíduos em laboratório com ambiente controlado demonstraram ausência de ritmicidade da IL-1 e presença de ritmicidade da IL-6 tanto no sangue quanto na saliva. Conclusão: Trabalhadores noturnos estavam dessincronizados e apresentaram privação parcial de sono. O período de férias levou ao aumento da duração do sono; aumento da secreção de melatonina medida pela 6-sulfatoximelatonina, além da diminuição da sonolência, fadiga, dor e concentração de IL-1. Esses achados evidenciam as consequências negativas na saúde que o turno noturno de trabalho pode ocasionar e demonstram que há parcial reversão desses efeitos nas férias. / Introduction: A recognized consequence of night shift work on employees is the loss of internal temporal order, which results in pathophysiological alterations. Objective: This study aimed to evaluate the effects of night shift work on the level and circadian rhythm of inflammatory cytokines of line workers and machine operators. Methods: A cross-sectional study was conducted in a beverage company. On stage 1 of the study, demographic data, living and leisure conditions, work conditions and organization, morbidity, musculoskeletal symptoms, fatigue, excessive sleepiness and anthropometric data of 123 workers (56 fixed day workers and 67 fixed night shift workers) were evaluated. Fifteen volunteers from day shift, 15 from night shift, and 15 from the same night shift during vacation participated in stage 2. During seven consecutive days, data were collected regarding the pattern of sleep and wakefulness. Also, on one work day and one day off, within this 7 days, saliva samples were collected every three hours while subjects were awake to evaluate melatonin, IL-1 and IL-6, in addition to drowsiness, fatigue and pain data were also collected. Furthermore, urine samples were collected to measure 6-sulphatoxymelatonin after the main sleep episode. Mean differences between groups and analysis of Odds Ratio were used to evaluate the data collected on stage 1. For the analysis of data collected on stage 2, Nested ANOVA followed by Dunnet contrast test were used in order to compare the three groups (Day, Night and Night-vacation). On stage 3, salivary and blood IL-1, IL-6 and TNF- citokine curves from seven healthy subjects kept in a controled laboratory environment were compared. Individual and populational Cosinor was the method used to verify circadian rhythmicity in stage 2 and 3. Results: The results showed that night workers had lower amplitude of the rhythm of salivary melatonin then day workers. Although the concentration of 6-sulphatoxymelatonin was lower among night shift workers compared to day workers, its concentration was higher during vacation time. During vacation, an increase in sleep duration was observed, even though no differences between the main parameters of sleep and nap between day and night workers during work period were found. However, the IL-6 cytokine acrophase occurred in similar periods among the three groups, even though the night shift workers had a higher concentration of this cytokine. The IL-1 showed rhythmicity only for day workers. There was no difference in the prevalence of diseases among day and night workers. The data collected from healthy subjects in controlled environment showed absence of rhythmicity for IL-1, but presence of rhythmicity for IL-6 present in both blood and saliva. Conclusion: Night shift workers were desynchronized and showed signs of partial sleep deprivation. During vacation, sleep duration was increased; melatonin secretion measured by the 6-sulphatoxymelatonin was increased, in addition to decreased drowsiness, fatigue, pain and concentration of IL-1. These findings highlight the negative health consequences that night shift work can cause and show that there are partial reverse effects of these changes during vacation.
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L’association entre les symptômes de la dépression chez les adolescents et l’alimentation nocturne chez les jeunes adultesGuentcheva, Iliana 08 1900 (has links)
No description available.
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Efeitos do trabalho noturno nos ritmos circadianos de marcadores do processo inflamatório / Effects of night work on circadian rhythms of markers of inflammationLeana Gonçalves Araujo Burgos 22 June 2015 (has links)
Introdução: Uma das reconhecidas consequências do trabalho noturno nos trabalhadores é a perda da ordem temporal interna, a qual resulta em alterações fisiopatológicas. Objetivo: O presente estudo teve o objetivo de avaliar os efeitos do turno noturno de traballho na concentração e no ritmo circadiano de citocinas inflamatórias de trabalhadores de linha de produção e operadores de máquinas. Material e Métodos: Estudo transversal realizado em uma empresa do setor de bebidas. Na Etapa 1 foram avaliados em 123 trabalhadores (56 do turno fixo diurno e 67 do turno fixo noturno), dados sociodemográficos, condições de vida e lazer, condições e organização do trabalho, morbidades, sintomas osteomusculares, fadiga, sonolência excessiva e dados antropométricos. Quinze voluntários do turno diurno, 15 do turno noturno em período de trabalho e em momento de férias participaram da Etapa 2. Durante sete dias foram coletados dados do padrão de sono e vigília e em um Dia de Trabalho e um Dia de Folga foram realizadas coletas salivares em intervalos de três horas, durante a vigília, para estimar a concentração de melatonina, IL-1 e IL-6, além de coletados dados de sonolência, fadiga e dor. Também foi realizada coleta de urina para medir 6-sulfatoximelatonina após o episódio principal de sono. Foram verificadas diferenças de médias entre os dados dos grupos obtidos na Etapa 1, assim como análises de Odds Ratio. A ANOVA Nested foi utilizada na Etapa 2 para comparar os grupos (Diurno, Noturno e Noturno-Férias), seguida do teste de contraste de Dunnet. A Etapa 3 comparou a curva das citocinas IL-1, IL-6 e TNF- na saliva e no sangue em 7 indivíduos saudáveis em laboratório. O método do Cosinor individual e populacional foi aplicado para verificar ritmicidade circadiana. Resultados: Os resultados revelaram que os trabalhadores noturnos tinham menor amplitude do ritmo da melatonina salivar que os diurnos. Embora a concentração de 6-sulfatoximelatonina também tenha sido menor entre os trabalhadores noturnos comparados com os diurnos, sua concentração foi mais elevada durante as férias. Nas férias se observou um aumento da duração do sono, apesar de não ter sido verificada nenhuma diferença entre os parâmetros do sono principal e do cochilo entre os trabalhadores dos turnos diurnos e noturno no período de trabalho. No entanto, a acrofase da citocina IL-6 ocorreu em horário similar nos três grupos, ainda que os trabalhadores noturnos tenham apresentado maior concentração dessa citocina. A IL-1 apresentou ritmicidade apenas para o grupo diurno. Não houve diferença na prevalência de doenças entre os Grupos Diurno e Noturno. Os dados com os indivíduos em laboratório com ambiente controlado demonstraram ausência de ritmicidade da IL-1 e presença de ritmicidade da IL-6 tanto no sangue quanto na saliva. Conclusão: Trabalhadores noturnos estavam dessincronizados e apresentaram privação parcial de sono. O período de férias levou ao aumento da duração do sono; aumento da secreção de melatonina medida pela 6-sulfatoximelatonina, além da diminuição da sonolência, fadiga, dor e concentração de IL-1. Esses achados evidenciam as consequências negativas na saúde que o turno noturno de trabalho pode ocasionar e demonstram que há parcial reversão desses efeitos nas férias. / Introduction: A recognized consequence of night shift work on employees is the loss of internal temporal order, which results in pathophysiological alterations. Objective: This study aimed to evaluate the effects of night shift work on the level and circadian rhythm of inflammatory cytokines of line workers and machine operators. Methods: A cross-sectional study was conducted in a beverage company. On stage 1 of the study, demographic data, living and leisure conditions, work conditions and organization, morbidity, musculoskeletal symptoms, fatigue, excessive sleepiness and anthropometric data of 123 workers (56 fixed day workers and 67 fixed night shift workers) were evaluated. Fifteen volunteers from day shift, 15 from night shift, and 15 from the same night shift during vacation participated in stage 2. During seven consecutive days, data were collected regarding the pattern of sleep and wakefulness. Also, on one work day and one day off, within this 7 days, saliva samples were collected every three hours while subjects were awake to evaluate melatonin, IL-1 and IL-6, in addition to drowsiness, fatigue and pain data were also collected. Furthermore, urine samples were collected to measure 6-sulphatoxymelatonin after the main sleep episode. Mean differences between groups and analysis of Odds Ratio were used to evaluate the data collected on stage 1. For the analysis of data collected on stage 2, Nested ANOVA followed by Dunnet contrast test were used in order to compare the three groups (Day, Night and Night-vacation). On stage 3, salivary and blood IL-1, IL-6 and TNF- citokine curves from seven healthy subjects kept in a controled laboratory environment were compared. Individual and populational Cosinor was the method used to verify circadian rhythmicity in stage 2 and 3. Results: The results showed that night workers had lower amplitude of the rhythm of salivary melatonin then day workers. Although the concentration of 6-sulphatoxymelatonin was lower among night shift workers compared to day workers, its concentration was higher during vacation time. During vacation, an increase in sleep duration was observed, even though no differences between the main parameters of sleep and nap between day and night workers during work period were found. However, the IL-6 cytokine acrophase occurred in similar periods among the three groups, even though the night shift workers had a higher concentration of this cytokine. The IL-1 showed rhythmicity only for day workers. There was no difference in the prevalence of diseases among day and night workers. The data collected from healthy subjects in controlled environment showed absence of rhythmicity for IL-1, but presence of rhythmicity for IL-6 present in both blood and saliva. Conclusion: Night shift workers were desynchronized and showed signs of partial sleep deprivation. During vacation, sleep duration was increased; melatonin secretion measured by the 6-sulphatoxymelatonin was increased, in addition to decreased drowsiness, fatigue, pain and concentration of IL-1. These findings highlight the negative health consequences that night shift work can cause and show that there are partial reverse effects of these changes during vacation.
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