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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.
51

Změny vnitřní stavby klastických sedimentárních hornin při zkoušce Schmidtovým kladivem / Modification of rock fabric of clastic sedimentary rocks due to the Schmidt hammer test

Snížek, Petr January 2013 (has links)
iv Summary Schmidt hammer is the instrument which is used for the assessment of rock mechanical properties and this instrument is classified as the indirect method. This method is based on the assessment of rebound value (R) of the Schmidt hammer, which is measurred by the amount of rebound of the impact plunger from the surface of tested rock. Schmidt hammer is called as the non-destructive method of rock assessment and it is called as in situ testing method as well. The main objective of this work is provement, that Schmidt hammer testing is destructive method and define degree of damage which is caused in the rock mass. Sedimentary rocks were used for the testing, mostly sandstones and arkose sandstones with different types of cement. This made it possible to test the fraction of the rock mass and the relation between fraction and type of cement. The clasts of the rocks had different properties than it was possible to find the relation between grain size and fraction of the rock. Already in procedure of the testing by Schmidt hammer it was obvious, that this metod is definitely destructive. Rock surface after hitting by plunger of Schmidt hammer gains macroscopically observeable destruction. On the surface is the circular track of the plunger and the surface is grinded. It is possible to wipe the small...
52

Évolution des mécanismes de production et de régulation du sommeil paradoxale au cours du vieillissement chez le rat : implication de la NO-synthase inductible : conséquences sur la réponse au stress : rétablissement de la réponse au stress par un antidépresseur / Evolution of executive and permissive mechanisms of paradoxical sleep during aging in the rat : implication of the inducible NO-synthase : effects on the stress response : recovery of the stress response with an antidepressant

Descamps Lefebvre, Amandine 16 November 2009 (has links)
Cette étude a analysé l’influence qu’exerce le vieillissement sur les mécanismes du sommeil chez le rat. Dans un premier temps, nous avons abordé le rôle joué par la NO-synthase inductible (iNOS) dans la régulation du sommeil paradoxal (SP). Nous rapporterons que l’injection d’un inhibiteur spécifique de la iNOS dans le tegmentum latérodorsal (LDT), inhibe l’apparition du SP chez le rat âgé (24 mois) mais pas chez l’adulte (4 mois). Cet effet est antagonisé par une injection secondaire d’un donneur de NO. Les corps cellulaires exprimant la iNOS sont localisés dans des noyaux voisins du LDT, mais, seuls des prolongements neuronaux expriment la iNOS dans ce noyau. Aucune expression de la iNOS n’est apparente dans le cerveau du rat adulte. Ces résultats sont la première preuve du rôle joué par la iNOS dans la régulation du SP chez l’animal âgé. Nous avons ensuite comparé la capacité des rats adultes et âgés à répondre à un stress d’immobilisation sur le plan polysomnographique. Les résultats obtenus confirment que, chez le rat adulte, le stress d’immobilisation d’une heure, imposé en début de période d’obscurité, provoque un rebond de SP. Chez l’animal âgé, au contraire, le stress d’immobilisation reste sans effets sur les états de veille et de sommeil. Enfin, nous avons tenté de mettre en évidence si l’agomélatine, un antidépresseur de nouvelle génération, était capable de compenser l’absence de rebond de SP observée chez l’animal âgé après un stress d’immobilisation. Les résultats obtenus indiquent que l’agomélatine, administrée au début de la période d’obscurité pendant 3 jours consécutifs, pouvait vraisemblablement favoriser la réapparition d’un rebond de SP / This study analysed the influence exerted by aging on the rat sleep-wake cycle. We first considered the part played by the inducible NO-synthase (iNOS) in the regulation of paradoxical sleep (PS or REM sleep). We report that the injection of an iNOS inhibitor, within the laterodorsal pontin tegmentum (LDT), suppresses the occurrence of PS in the aged animals (24 months), but not in the adult ones (4 months). This effect can be reversed by a secondary injection of a NO donor. While the cell bodies expressing the iNOS are localized in the structures neighbouring the LDT, only nerves ending impinge this nucleus. The iNOS is not expressed in the brain of the adult rat. These data constitute the first demonstration of the part played by the iNOS in the regulation of PS in the aged animal. Afterwards, we compared the ability of adult and aged rats to reply to an immobilization stress by a sleep rebound. Data obtained confirm that a sleep rebound occurs after a 1h immobilization stress in the adult rat. In the same conditions, such a sleep rebound is not observed in the aged animal. Finally, we checked whether agomelatine, a new type of antidepressant, was able to compensate the loss of the sleep rebound observed in the aged rat after an immobilization stress. Data obtained indicate that agomelatine, administered at the beginning of the dark period during 3 consecutive days, might facilitate the occurrence of a sleep rebound related to stress in the aged rat
53

Reviewing environmental rebound effects from peer-to-peer boat sharing in Finland

Warmington-Lundström, Jon January 2019 (has links)
The world crucially needs to reduce the level of emissions being released in the environment in order to combat climate change. With the global population increasing and economies continuing to grow, the circular economy has been heralded by many as the potential solution to economic prosperity whilst also reducing primary resource use and emissions. However, the existence of environmental rebound effect has the potential to severely limit the emission reductions of the circular economy by increasing consumption elsewhere. This paper focuses on the definition of economic rebound effect and on its impact on a peer-to-peer boat sharing platform in Finland. A survey completed by users of the platform allowed for the quantitative analysis of environmental rebound effect experienced by the users and also provide insight into the consumption behaviour that created the most negative consequences. Rebound was experienced by almost all users with almost a third of users experiencing a backfire in which their overall emissions increased as a result of consumption made possible by the economic benefits of shared access. Primary production and the substitution of air travel for the leasing of a boat created large reductions in emissions, however, this was counteracted by increases in personal use and increased air travel by others. This real-life study of environmental rebound effect shows both its existence and impact on the peer-to-peer sharing of boats in Finland.
54

Excesso de peso corporal na adolescência segundo períodos críticos para a gênese da obesidade durante a infância / Excessive body weight during adolescence according to critical periods for the development of obesity in infancy

Nasr, Elizabeth Maria Bismarck 11 May 2012 (has links)
Introdução: Considerando-se a dificuldade e o elevado custo para o tratamento da obesidade, e seu papel como fator de risco para diversas patologias, sua prevenção mostra-se fundamental, por este motivo, a identificação precoce de fatores de risco evitáveis, como a inadequação do estado nutricional em períodos críticos para a gênese da obesidade, representa um interessante campo para investigação científica. Objetivo: Verificar a relação entre o excesso de peso corporal em adolescentes segundo estado nutricional ao nascer e excesso de peso durante o primeiro ano de vida e no período de repleção da adiposidade. Método: Participaram deste estudo alunos de ambos os sexos matriculados nos quintos e sextos anos de Unidades Escolares no Município de São José dos Campos-SP. A coleta de dados ocorreu em três etapas, a primeira consistiu na avaliação nutricional durante a adolescência, considerando-se as medidas de índice de massa corporal (IMC), circunferências abdominal e do braço e soma das pregas cutâneas triciptal e subescapular. Na segunda etapa foram coletadas informações referentes à escolaridade materna, aleitamento materno e estado nutricional ao nascer por meio de questionário respondido pelos pais. As crianças foram classificadas segundo os índices peso ao nascer por idade gestacional, índice ponderal ao nascer e peso ao nascer. Na última etapa foram obtidas informações de peso e estatura durante a infância nos prontuários de atendimento das Unidades Básicas de Saúde (UBS) do Município. Realizou-se análise de regressão logística para verificar associação entre excesso de peso aos 10 anos de idade, considerada variável dependente e, como variáveis independentes, estado nutricional ao nascer, excesso de peso corporal no primeiro ano de vida e no período de repleção da adiposidade (entre os 5 e 7 anos de idade). As análises foram ajustadas para demais variáveis. Resultados: Os estudantes apresentaram média (desvio-padrão) de 131,3 meses (10,99) de idade. Verificou-se elevada correlação entre o peso e comprimento ao nascer informado pelos responsáveis e registrado no prontuário das UBSs (coeficiente de correlação: 0,95 e 0,98, respectivamente). Com relação ao estado nutricional ao nascer, observou-se que o elevado peso ao nascer e o peso ao nascer pequeno para idade gestacional associaram-se ao excesso de peso corporal no início da adolescência. Foi identificado limiar de associação entre excesso de peso corporal no primeiro ano de vida e aos 10 anos de idade. Também foi encontrada associação entre excesso de peso corporal na adolescência e no período de repleção da adiposidade. Conclusão: Os achados mostram consistência com a hipótese de que períodos críticos do crescimento acarretariam em maior predisposição ao excesso de gordura corporal, identificada no presente estudo no início da adolescência / Introduction: Considering that obesity is a major risk for many diseases as well as the difficulties and elevated costs for its treatment, its prevention and the identification of early avoidable health risks, such as nutritional status in critical periods of life, represent important aspects for scientific investigation. Objective: Verify the relationship between excessive body weight during adolescence according to birth nutrition status and excessive body weight during the first year of life and at the period of adiposity rebound. Method: This study was conducted with schoolchildren of both sexes, enrolled in Public Schools in São José dos Campos - SP (SJC-SP). The data was collected in 3 phases, the first consisted of collecting anthropometric information during adolescence, considering body mass index (BMI), arm and abdominal circumferences and the sum of skin fold thickness (triceps and sub scapular). Information about mother´s education, breastfeeding and birth nutritional status was collected in the second phase through a survey which the parents answered. The children were classified according to birth weight for gestational age, ponderal index and birth weight. In the last phase, information about nutritional status during infancy was obtained from medical registers of primary health units in the city. Logistical regression analyses were made to investigate the association between excessive body weight at 10 years of age, considered as dependent variable and, as independent variables, the nutritional status at time of birth, the first year of age and during the period of adiposity rebound (between 5 and 7 years of age). The analyses were adjusted by other variables. Results: The students presented a mean of 131.3 months of age (10.99). An elevated correlation was observed between parents information about birth weight and length and the information registered at the medical documents of primary health units in the city (Correlation coefficient: 0.95 and 0.98, for weight and for length, respectively). An association between elevated birth weight and birth weight small for gestational age and excessive body weight during adolescence was observed. A weak association between excessive body weight during the first year of life and at 10 years of age was identified. It was also verified association in relation to adiposity during the period of adiposity rebound and excessive weight at 10 years of age. Conclusion: These results show consistency in the hypothesis that the critical period for growth development could predispose to future obesity, identified in the present study during early adolescence
55

Análise de prova de carga dinâmica em estacas metálicas do tipo trilho / Analysis of dynamic load tests on steel crane rail piles

Lima, Floriano Medeiros de Andrade 21 December 1999 (has links)
Este trabalho apresenta a análise de provas de carga dinâmica realizadas em estaca metálicas tipo trilho (TR - 68) cravadas no Campo Experimental de Fundações da USP/São Carlos. As estacas possuem segmentos de 12 e de 3 m, soldados segundo a NBR 8800/86, totalizando um comprimento máximo 27 m. Os objetivos desta análise são: 1) realizar um estudo abrangente da capacidade de carga do tipo trilho, 2) verificar a utilização de trilho usado como elemento estrutural de fundação, 3) comprovar o uso do repique como método de controle do estaqueamento, 4) demostrar a importância da energia crescente na prova de carga dinâmica. As medidas de repique foram realizadas com o uso de papel e lápis em vinte estacas, para níveis crescentes de energia. A energia foi aplicada pelo martelo de gravidade caindo de uma altura de 0,20 - 0,40 - 0,60 - 0,80 - 1,00 - 1,20 e 1,50 m. A capacidade de carga das estacas, determinada pela extrapolação da curva carga mobilizada - deslocamento, foi comparada com os valores obtidos pelos métodos de previsão da prática brasileira, bem como com os resultados de dois ensaios com PDA (Pile Driving Analyzer) e também com uma prova de carga estática, realizados em estacas representativas. / This paper presents an analysis of dynamic load tests performed on steel crane rails piles (TR-68) at the Experimental Foundation Field of USP/São Carlos. The piles have segments of 12 and 3 m, welded according to NBR 8800/86, comprising a maximum driving length of 27 m. The objectives of this analysis are: 1) to carry out a wide study of steel track pile bearing capacity, 2) verify the utilization of the steel crane rails piles with structural element of foundation, 3) to prove the use of the rebound with the control method of driving piles. 4) to demonstrate the importance of increasing energy in the dynamic load test. The rebound measurements were performed with paper and pencil in twenty piles and were analyzed by applying increasing energy level. The energy was applied by the gravity hammer falling of a drop heights of 0.2 - 0.4 - 0.6 - 0.8 - 1.0 - 1.2 and 1.5 m. The pile bearing capacity, determined by the extrapolations of the mobilized resistance - displacement curves was compared to the Brazilian experience methods, as well as to two load tests employing the Pile Driving Analyzer (PDA) and to one static load test carried out on representative piles.
56

Excesso de peso corporal na adolescência segundo períodos críticos para a gênese da obesidade durante a infância / Excessive body weight during adolescence according to critical periods for the development of obesity in infancy

Elizabeth Maria Bismarck Nasr 11 May 2012 (has links)
Introdução: Considerando-se a dificuldade e o elevado custo para o tratamento da obesidade, e seu papel como fator de risco para diversas patologias, sua prevenção mostra-se fundamental, por este motivo, a identificação precoce de fatores de risco evitáveis, como a inadequação do estado nutricional em períodos críticos para a gênese da obesidade, representa um interessante campo para investigação científica. Objetivo: Verificar a relação entre o excesso de peso corporal em adolescentes segundo estado nutricional ao nascer e excesso de peso durante o primeiro ano de vida e no período de repleção da adiposidade. Método: Participaram deste estudo alunos de ambos os sexos matriculados nos quintos e sextos anos de Unidades Escolares no Município de São José dos Campos-SP. A coleta de dados ocorreu em três etapas, a primeira consistiu na avaliação nutricional durante a adolescência, considerando-se as medidas de índice de massa corporal (IMC), circunferências abdominal e do braço e soma das pregas cutâneas triciptal e subescapular. Na segunda etapa foram coletadas informações referentes à escolaridade materna, aleitamento materno e estado nutricional ao nascer por meio de questionário respondido pelos pais. As crianças foram classificadas segundo os índices peso ao nascer por idade gestacional, índice ponderal ao nascer e peso ao nascer. Na última etapa foram obtidas informações de peso e estatura durante a infância nos prontuários de atendimento das Unidades Básicas de Saúde (UBS) do Município. Realizou-se análise de regressão logística para verificar associação entre excesso de peso aos 10 anos de idade, considerada variável dependente e, como variáveis independentes, estado nutricional ao nascer, excesso de peso corporal no primeiro ano de vida e no período de repleção da adiposidade (entre os 5 e 7 anos de idade). As análises foram ajustadas para demais variáveis. Resultados: Os estudantes apresentaram média (desvio-padrão) de 131,3 meses (10,99) de idade. Verificou-se elevada correlação entre o peso e comprimento ao nascer informado pelos responsáveis e registrado no prontuário das UBSs (coeficiente de correlação: 0,95 e 0,98, respectivamente). Com relação ao estado nutricional ao nascer, observou-se que o elevado peso ao nascer e o peso ao nascer pequeno para idade gestacional associaram-se ao excesso de peso corporal no início da adolescência. Foi identificado limiar de associação entre excesso de peso corporal no primeiro ano de vida e aos 10 anos de idade. Também foi encontrada associação entre excesso de peso corporal na adolescência e no período de repleção da adiposidade. Conclusão: Os achados mostram consistência com a hipótese de que períodos críticos do crescimento acarretariam em maior predisposição ao excesso de gordura corporal, identificada no presente estudo no início da adolescência / Introduction: Considering that obesity is a major risk for many diseases as well as the difficulties and elevated costs for its treatment, its prevention and the identification of early avoidable health risks, such as nutritional status in critical periods of life, represent important aspects for scientific investigation. Objective: Verify the relationship between excessive body weight during adolescence according to birth nutrition status and excessive body weight during the first year of life and at the period of adiposity rebound. Method: This study was conducted with schoolchildren of both sexes, enrolled in Public Schools in São José dos Campos - SP (SJC-SP). The data was collected in 3 phases, the first consisted of collecting anthropometric information during adolescence, considering body mass index (BMI), arm and abdominal circumferences and the sum of skin fold thickness (triceps and sub scapular). Information about mother´s education, breastfeeding and birth nutritional status was collected in the second phase through a survey which the parents answered. The children were classified according to birth weight for gestational age, ponderal index and birth weight. In the last phase, information about nutritional status during infancy was obtained from medical registers of primary health units in the city. Logistical regression analyses were made to investigate the association between excessive body weight at 10 years of age, considered as dependent variable and, as independent variables, the nutritional status at time of birth, the first year of age and during the period of adiposity rebound (between 5 and 7 years of age). The analyses were adjusted by other variables. Results: The students presented a mean of 131.3 months of age (10.99). An elevated correlation was observed between parents information about birth weight and length and the information registered at the medical documents of primary health units in the city (Correlation coefficient: 0.95 and 0.98, for weight and for length, respectively). An association between elevated birth weight and birth weight small for gestational age and excessive body weight during adolescence was observed. A weak association between excessive body weight during the first year of life and at 10 years of age was identified. It was also verified association in relation to adiposity during the period of adiposity rebound and excessive weight at 10 years of age. Conclusion: These results show consistency in the hypothesis that the critical period for growth development could predispose to future obesity, identified in the present study during early adolescence
57

Desenvolvimento de uma metodologia analítica  por LC-MS/MS para determinação de meta-clorofenilpiperazina em plasma de camundongos submetidos à privação de sono paradoxal / Development of an analytical methodology by LC-MS/MS for determination of meta-chlorophenylpiperazine in plasma of mice submitted to paradoxical sleep deprivation

Polesel, Daniel Ninello 13 December 2012 (has links)
O aumento no uso abusivo e nas apreensões de comprimidos contendo 1-(3-clorofenil)piperazina (mCPP) têm sido observado na Europa desde o final do século 20. A mCPP promove efeitos semelhantes a metilenodioximetanfetamina (ecstasy) e surgiu como uma alternativa menos neurotóxica. Os principais efeitos descritos pelos usuários são sensação de bem-estar, euforia e empatia. Os efeitos adversos observados em casos de intoxicação aguda são a ansiedade, confusão, insônia, ataques de pânico, estados convulsivos, taquicardia e até mesmo a morte. A mCPP frequentemente tem seu uso associado com a privação de sono dos usuários em ambientes noturnos (festas e danceterias). Além disso, o fármaco provoca insônia no usuário, agravando ainda mais as consequências ao sono do indivíduo. O sono REM, em humanos, ou chamado de sono paradoxal nos animais, é uma fase importante do sono, por ser ela a fase de retorno da homeostasia comportamental e bioquímica. O objetivo deste trabalho foi avaliar os efeitos comportamentais dos isômeros da clorofenilpiperazina e desenvolver um método analítico para identificar e quantificar a mCPP em amostras de plasma de camundongos submetidos à privação de sono paradoxal (PSP) por 24 e 48 horas. A ferramenta analítica empregada para identificar e quantificar a mCPP foi a cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS). As análises comportamentais de ansiedade e atividade locomotora dos camundongos utilizaram os testes do Labirinto em Cruz Elevado e o teste do Campo Aberto, respectivamente. Os resultados mostraram que a associação da PSP com o uso da mCPP acarretou mudanças comportamentais que voltaram ao nível homeostásico somente após 48 horas de rebote de sono. Além disso, observou-se um aumento significativo na concentração circulante de mCPP nos animais PSP por 48 horas em relação ao grupo controle. Por fim, concluiu-se que a privação de sono paradoxal associada com a administração da mCPP produziu graves consequências comportamentais em camundongos e que a concentração do fármaco encontrado no plasma foi maior nos animais submetidos à privação de sono paradoxal. / The increase on abusive use and seizures of tablets containing 1-(3-chlorophenyl)piperazine (mCPP) have been seen in Europe since the late 20th century. The mCPP promotes effects similar to methylenedioxymethamphetamine (ecstasy) and emerged as a less neurotoxic alternative. The main effects described by users are sense of well-being, euphoria and empathy. The adverse events observed in acute poisoning cases are anxiety, confusion, insomnia, panic attacks, convulsive states, tachycardia and even death. mCPP is often associated with sleep deprivation by their users and on night scenery (parties and discos). In addition, the drug causes insomnia on user, further aggravating the consequences to the individual sleep. REM sleep in humans or referred as to paradoxical sleep, in animals, is an important sleep phase, because it was the phase which promote the return of behavioral and biochemical homeostasis. The aim of this study was to evaluate the behavioral effects of the isomers of chlorophenylpiperazine and develop an analytical method to identify and quantify the mCPP in plasma samples from mice subjected to paradoxical sleep deprivation (PSD) for 24 and 48 hours. The analytical tool used to identify and quantify the mCPP was liquid chromatography coupled to mass spectrometry (LC-MS/MS). The behavioral analysis of anxiety and locomotor activity of mice used the Elevated Plus Maze and Open Field tests, respectively. The results showed that association of PSD with the use of mCPP led to behavioral changes that back to the homeostatic level only after 48 hours of rebound sleep. Furthermore, there was a significant increase in circulating concentration of mCPP in animals paradoxical sleep deprived for 48 hours compared to control group. Finally, it is concluded that paradoxical sleep deprivation associated with administration of mCPP produced severe behavioral effects in mice and concentration of drug found in plasma was greater in animals submitted to paradoxical sleep deprivation than control group.
58

Understanding the drivers behind high energy consumption within UK households : an interdisciplinary approach

Wang, Xinfang January 2018 (has links)
Anthropogenic climate change is a global problem that affects every country and each individual. The UK introduced its own carbon budgets, aiming to reduce its GHGs by 80% by 2050 compared with 1990 levels. The United Nations Conference of the Parties in Paris in 2015 came to an agreement on limiting the global average temperature rise to "well below 2oC". It has been argued that the Paris Agreement requires deeper and more rapid emission reductions than current UK targets. The CO2 emissions from energy use by households account for almost a third of total CO2 emissions in the UK in recent years. The research aims to explore drivers of high energy consumption in order to identify where there may be intervention points that can achieve a greater level of emission reductions than conventional policy tools in the short to medium term. Previous studies have focused on either socioeconomic factors or practices to explore household energy consumption and CO2 emissions, but have not integrated both aspects to identify drivers behind high energy consumption. To address this gap in the literature, the research applies an interdisciplinary approach to analyse the interconnected factors impacting on household energy consumption and CO2 emissions. Socioeconomic characteristics and practice theory are combined in order to understand how and why energy is consumed at home, and specifically to explore high energy consumption and related CO2 emissions at the household level. Both quantitative cluster analyses based on household socioeconomic factors and qualitative data collection and thematic analyses on energy-related practices at home have been conducted in the research. Results indicate that various combinations of socioeconomic factors and dwelling-related characteristics can collectively lead to high CO2 emissions from energy use at home. Nonetheless, these characteristics cannot fully explain why some households are high emitters, as they still share a variety of similar characteristics with average households in the UK. Besides household socioeconomic factors and dwelling-related characteristics, the materials, procedure and meanings of practices; people's discursive and practical consciousness; and dominant meanings of the home, also collectively influence energy use at home. Policymakers should consider not only improving the energy efficiency of the dwelling and appliances, but also how people's hidden knowledge and routines allow or constrain the performance of energy-related practices, as well as how the existing meanings of practices and dominant meanings of the home can be supported with less energy input and associated CO2 emissions. Energy efficiency related policies could focus more on how to reduce the interruption to people's everyday lives and the level of space loss. Policymakers could also work with different stakeholders, such as local authorities and community groups to tackle the challenges of installation of double gazing, cavity wall and roof insulation in the private rented sector. Policies for promoting renewable electricity micro-generation in the UK can target more effectively the high emitters who are at home most weekdays, as they can be more flexible in rearranging their use of appliances in daily routines and potentially reduce energy consumption during the peak time. In addition to combining a novel range of approaches and perspectives to understanding energy use at home, the research makes a contribution to achieving deeper and more rapid emission reductions in the short to medium term in the UK by focusing on the drivers behind high energy consumption at home than average energy consumption in general.
59

Desenvolvimento de uma metodologia analítica  por LC-MS/MS para determinação de meta-clorofenilpiperazina em plasma de camundongos submetidos à privação de sono paradoxal / Development of an analytical methodology by LC-MS/MS for determination of meta-chlorophenylpiperazine in plasma of mice submitted to paradoxical sleep deprivation

Daniel Ninello Polesel 13 December 2012 (has links)
O aumento no uso abusivo e nas apreensões de comprimidos contendo 1-(3-clorofenil)piperazina (mCPP) têm sido observado na Europa desde o final do século 20. A mCPP promove efeitos semelhantes a metilenodioximetanfetamina (ecstasy) e surgiu como uma alternativa menos neurotóxica. Os principais efeitos descritos pelos usuários são sensação de bem-estar, euforia e empatia. Os efeitos adversos observados em casos de intoxicação aguda são a ansiedade, confusão, insônia, ataques de pânico, estados convulsivos, taquicardia e até mesmo a morte. A mCPP frequentemente tem seu uso associado com a privação de sono dos usuários em ambientes noturnos (festas e danceterias). Além disso, o fármaco provoca insônia no usuário, agravando ainda mais as consequências ao sono do indivíduo. O sono REM, em humanos, ou chamado de sono paradoxal nos animais, é uma fase importante do sono, por ser ela a fase de retorno da homeostasia comportamental e bioquímica. O objetivo deste trabalho foi avaliar os efeitos comportamentais dos isômeros da clorofenilpiperazina e desenvolver um método analítico para identificar e quantificar a mCPP em amostras de plasma de camundongos submetidos à privação de sono paradoxal (PSP) por 24 e 48 horas. A ferramenta analítica empregada para identificar e quantificar a mCPP foi a cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS). As análises comportamentais de ansiedade e atividade locomotora dos camundongos utilizaram os testes do Labirinto em Cruz Elevado e o teste do Campo Aberto, respectivamente. Os resultados mostraram que a associação da PSP com o uso da mCPP acarretou mudanças comportamentais que voltaram ao nível homeostásico somente após 48 horas de rebote de sono. Além disso, observou-se um aumento significativo na concentração circulante de mCPP nos animais PSP por 48 horas em relação ao grupo controle. Por fim, concluiu-se que a privação de sono paradoxal associada com a administração da mCPP produziu graves consequências comportamentais em camundongos e que a concentração do fármaco encontrado no plasma foi maior nos animais submetidos à privação de sono paradoxal. / The increase on abusive use and seizures of tablets containing 1-(3-chlorophenyl)piperazine (mCPP) have been seen in Europe since the late 20th century. The mCPP promotes effects similar to methylenedioxymethamphetamine (ecstasy) and emerged as a less neurotoxic alternative. The main effects described by users are sense of well-being, euphoria and empathy. The adverse events observed in acute poisoning cases are anxiety, confusion, insomnia, panic attacks, convulsive states, tachycardia and even death. mCPP is often associated with sleep deprivation by their users and on night scenery (parties and discos). In addition, the drug causes insomnia on user, further aggravating the consequences to the individual sleep. REM sleep in humans or referred as to paradoxical sleep, in animals, is an important sleep phase, because it was the phase which promote the return of behavioral and biochemical homeostasis. The aim of this study was to evaluate the behavioral effects of the isomers of chlorophenylpiperazine and develop an analytical method to identify and quantify the mCPP in plasma samples from mice subjected to paradoxical sleep deprivation (PSD) for 24 and 48 hours. The analytical tool used to identify and quantify the mCPP was liquid chromatography coupled to mass spectrometry (LC-MS/MS). The behavioral analysis of anxiety and locomotor activity of mice used the Elevated Plus Maze and Open Field tests, respectively. The results showed that association of PSD with the use of mCPP led to behavioral changes that back to the homeostatic level only after 48 hours of rebound sleep. Furthermore, there was a significant increase in circulating concentration of mCPP in animals paradoxical sleep deprived for 48 hours compared to control group. Finally, it is concluded that paradoxical sleep deprivation associated with administration of mCPP produced severe behavioral effects in mice and concentration of drug found in plasma was greater in animals submitted to paradoxical sleep deprivation than control group.
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Income, Energy Taxation, and the Environment : An Econometric analysis

Ghalwash, Tarek January 2006 (has links)
<p>This thesis consists of four papers: two of them deal with the relationship between consumption, energy taxation, and emissions on macro level, and two of them focuses on the effects of changes in consumption and income on the environmental quality on a micro level.</p><p>The main objective of paper [I] is to examine how exogenous technological progress, in terms of an increase in energy efficiency, affects consumption choice by Swedish households and thereby emissions of carbon dioxide (CO2), sulphur dioxide (SO2) and nitrogen oxide (NOx). The aim of the paper is closely related to the discussion of what is known as the “rebound effect”. To neutralise the rebound effect, we estimate the necessary change in CO2 tax, i.e. the CO2 tax that keeps CO2 emissions at their initial level. In addition, we estimate how this will affect emissions of sulphur dioxide and nitrogen oxides. The results indicate that an increase in energy efficiency of 20 percent will increase emissions of CO2 by approximately 5 percent. To reduce the CO2 emissions to their initial level, CO2 tax must be raised by 130 percent. This tax increase will reduce the emissions of sulphur dioxide to below their initial level, but will leave the emissions of nitrogen oxides at a higher level than initially.</p><p>One of the premises implied in paper [II] is that the changes in consumer prices, as a result of changes in environmental taxes, may send a different signal to the consumer compared with other changes in consumer prices, such as changes in producer price. In addition, this assumed difference in the signaling effect of the changes in environmental taxes, compared to changes in the producer price, may also differ between different commodities. To achieve the objectives a system of demand functions for Swedish households is estimated. To test for the signalling effect of environmental taxes the consumer price for energy goods is partitioned into a producer price part and a tax part.</p><p>In Paper [III], we estimate the income elasticity of demand for recreational services and other traditional groups of goods in Sweden and we test for potential changes in such estimates over the twentieth century. The paper uses Swedish household surveys for the years 1913, 1984, 1988, and 1996. Because of the difficulty of directly observing the demand for recreational services, we employ an indirect methodology by using the demand for some outdoor goods as proxies for the recreational services demand.</p><p>In paper [IV], we investigate the relationship between pollution and income at the household level. Here we want to investigate, and hence contribute to the existing literature, under what conditions concerning individual preferences and the link between consumption and pollution a linear relationship are to be expected, but also to empirically assess the relationship. To achieve our objective we formulate a model determining different type of households’ choice of consumption for goods. Furthermore we link the demand model to emission functions for the various goods. The results from the empirical analysis show that, at least in a close neighbourhood of observed income/pollution, we can reject linearity for all three types of pollutions, CO2, SO2, and NOx. According to our results the pollution/income relationships are all strictly concave. Thus the implication is that the income distribution seems to matter in the sense that equalization of income will lead to higher emissions. Furthermore it is shown that the slope as well as the curvature differs between different types of households, which means that preferences differ across households.</p>

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