837 resultados para Salt stress. Osmolytes. Halobacteria and metagenome
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Caregivers are often under a great deal of stress while caring for their spouses with dementia. It is when the stress builds up and becomes overwhelming that the caregiver is at risk for developing depression. The primary objective of this study was to determine which cognitive and behavioral coping strategies are associated with lower levels of depression; once these strategies are identified, interventions can be established to educate these caregivers. Thirty-two spousal caregivers participated in this study. They each filled out a questionnaire, which contained three sections. The first section asked them for demographic information about themselves and their spouses; the second section consisted of a coping strategies scale; and, the third section contained a depression scale. Results of this study indicate that problem-focused coping strategies were associated with a lesser degree of depressive symptomatology, whereas most of the emotion-focused strategies were associated with a greater degree of depressive symptomatology among the present sample of spousal caregivers. In addition, no relationship was found between the length of time providing care to their spouses and their level of depression.
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Ocean acidification, recognized as a major threat to marine ecosystems, has developed into one of the fastest growing fields of research in marine sciences. Several studies on fish larval stages point to abnormal behaviours, malformations and increased mortality rates as a result of exposure to increased levels of CO2. However, other studies fail to recognize any consequence, suggesting species-specific sensitivity to increased levels of CO2, highlighting the need of further research. In this study we investigated the effects of exposure to elevated pCO2 on behaviour, development, oxidative stress and energy metabolism of sand smelt larvae, Atherina presbyter. Larvae were caught at Arrábida Marine Park (Portugal) and exposed to different pCO2 levels (control: 600 µatm, pH = 8.03; medium: 1000 µatm, pH = 7.85; high: 1800 µatm, pH = 7.64) up to 15 days, after which critical swimming speed (Ucrit), morphometric traits and biochemical biomarkers were determined. Measured biomarkers were related with: 1) oxidative stress-superoxide dismutase and catalase enzyme activities, levels of lipid peroxidation and DNA damage, and levels of superoxide anion production; 2) energy metabolism - total carbohydrate levels, electron transport system activity, lactate dehydrogenase and isocitrate dehydrogenase enzyme activities. Swimming speed was not affected by treatment, but exposure to increasing levels of pCO2 leads to higher energetic costs and morphometric changes, with larger larvae in high pCO2 treatment and smaller larvae in medium pCO2 treatment. The efficient antioxidant response capacity and increase in energetic metabolism only registered at the medium pCO2 treatment may indicate that at higher pCO2 levels the capacity of larvae to restore their internal balance can be impaired. Our findings illustrate the need of using multiple approaches to explore the consequences of future pCO2 levels on organisms.
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The use of fossil fuels has been considered one of reason for the increase of pollution in the atmosphere and it may be related to the climate changes. Then, the research of the new sources of fuels will be important. Considering this, the use of biodiesel has been considered not as bad as petrol. The castor bean (Ricinus communis L.) is an important oilseed, which belongs to Euphorbiaceae family, and the oil found in the seed has important characteristics for biodiesel. This plant is considered as “rustic” as it does not need so much water for its development and oil production. Due to this, this plant has been considered to be ideal in semi-arid regions, such as the Northeast of Brazil. The aim of his study is to better understand the responses to abiotic stresses (drought and salinity) from castor bean plants using morphological, physiological and molecular tools. In order to do this, the castor bean plants were subjected to salt stress (50, 100, 150 and 200 mM NaCl) in a controlled environment and drought stress (5, 10, 15 days and 10 days cyclic). After these treatments, these plants were subjected to different analyzes: a) the expansion and retention of water from leaves; b) anatomy using leaves and roots. Based on these results, we found that castor suffered decrease in leaf area with increase drought stress, however restricted water loss, probably by accumulation of compatible solutes in the leaves. The anatomy data showed modifications in the vascular system. These modifications observed suggested that castor bean plant may be resistant to stress as it was verified in 5 days of drought as well as in 100 mM NaCl. In both conditions, these plants were fine. Probably these plants keep some solutes in the cell and then maintain the cell tugor. The data obtained in this study gave a better idea how castor bean plant responds to abiotic stress conditions - drought and salt stress
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The condition and quality of cultured blue mussels (Mytilus edulis) are affected by various environmental characteristics including temperature, salinity, food concentration, composition and year-to-year variability, waves, tides, and currents. Mussels are a keystone species in the ecosystem, affecting the surrounding environment through filtration, biodeposition and nutrient recycling. This study evaluated the effects of culture depth and post-harvest handling on cultured blue mussels in Newfoundland, Canada. Depth was examined over two years; three shallow water (5 m depth) and three deep water sites (15 m depth) were compared for environmental characteristics, mussel physiological stress response, growth, and biochemical composition. The area examined presented complex hydrodynamic characteristics; deep water sites appeared to be located more often near or within the pycnocline than shallow water sites. Deep water sites presented lower temperatures than shallow sites from spring to fall. Physiological stress response varied seasonally, but was unaffected by culture depth. In Year 1 shallow and deep water mussels presented similar growth, while in Year 2 deep water mussels showed better final condition. Lipid and glycogen showed seasonal variation, but no significant differences between shallow and deep water were noted. Fatty acid profiles showed a higher content of omega-3s PUFA in deep water sites at the end of Year 2. Under extreme weather conditions, deep water appeared to provide a more stable environment for mussel growth than shallow water. Harvested mussels were kept under ambient live-holding conditions for one month during the fall, winter, and spring seasons. They were compared to freshly harvested mussels for condition, biochemical profile and palatability. A progressive loss of dry tissue weight and an increase in water content were shown over the holding period during the fall and spring seasons, when compared to field controls. The biochemical analysis suggested seasonal changes; differences in triacylglycerol content were found in the spring season when compared with controls. The palatability data indicated that the panellists were unable to determine a difference between mussels kept in holding and those freshly harvested from the site. This study presents new knowledge for mussel farming, especially in terms of environmental interactions and deep water culture.
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Background The growing prevalence and associated burden of diet-related non-communicable diseases is a global public health concern. The environments in which people live and work influences their dietary behaviours. Aim The focus of this thesis was on the effectiveness of complex workplace dietary interventions. The comparative effectiveness of a complex workplace environmental dietary modification intervention and an educational intervention were assessed both alone and in combination relative to a control workplace setting. Methods The systematic review was guided by the PRISMA statement. In a cluster controlled trial, four workplaces were purposively allocated to control, nutrition education alone (Education), environmental dietary modification alone (Environment) and nutrition education and environmental dietary modification (Combined intervention). The interventions were guided by the MRC framework. In the control workplace, data were collected at baseline and follow-up. In the intervention related sub-study, the relationships between nutrition knowledge, diet quality and hypertension were examined. Results The systematic review provided limited evidence. In the FCW study, 850 employees aged 18-64 years were recruited at baseline with N(response rate %) in each workplace as follows: Control: 111(72%), Education: 226(71%), Environment: 113(91%), Combined intervention: 400(61%). Complete follow-up data was obtained for 517 employees (61%). There were significant positive changes in dietary intakes of saturated fat(p=0.013), salt(p=0.010) and nutrition knowledge(p=0.034) between baseline and follow-up at 7-9 months in the combined intervention versus the control workplace in the fully adjusted multivariate analysis. Small but significant changes in BMI(-1.2kg/m2 (p=0.047) were also observed in the combined intervention. In the sub-study, nutrition knowledge was positively significantly associated with diet quality and blood pressure but no evidence of a mediation effect of the DASH score was detected between nutrition knowledge and blood pressure. Conclusion This thesis provides critical evidence on the effectiveness of complex workplace dietary interventions in a manufacturing working population.
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Far-field stresses are those present in a volume of rock prior to excavations being created. Estimates of the orientation and magnitude of far-field stresses, often used in mine design, are generally obtained by single-point measurements of stress, or large-scale, regional trends. Point measurements can be a poor representation of far-field stresses as a result of excavation-induced stresses and geological structures. For these reasons, far-field stress estimates can be associated with high levels of uncertainty. The purpose of this thesis is to investigate the practical feasibility, applications, and limitations of calibrating far-field stress estimates through tunnel deformation measurements captured using LiDAR imaging. A method that estimates the orientation and magnitude of excavation-induced principal stress changes through back-analysis of deformation measurements from LiDAR imaged tunnels was developed and tested using synthetic data. If excavation-induced stress change orientations and magnitudes can be accurately estimated, they can be used in the calibration of far-field stress input to numerical models. LiDAR point clouds have been proven to have a number of underground applications, thus it is desired to explore their use in numerical model calibration. The back-analysis method is founded on the superposition of stresses and requires a two-dimensional numerical model of the deforming tunnel. Principal stress changes of known orientation and magnitude are applied to the model to create calibration curves. Estimation can then be performed by minimizing squared differences between the measured tunnel and sets of calibration curve deformations. In addition to the back-analysis estimation method, a procedure consisting of previously existing techniques to measure tunnel deformation using LiDAR imaging was documented. Under ideal conditions, the back-analysis method estimated principal stress change orientations within ±5° and magnitudes within ±2 MPa. Results were comparable for four different tunnel profile shapes. Preliminary testing using plastic deformation, a rough tunnel profile, and profile occlusions suggests that the method can work under more realistic conditions. The results from this thesis set the groundwork for the continued development of a new, inexpensive, and efficient far-field stress estimate calibration method.
Colonialism, political unconscious and cognitive mapping in the space of the film "Captain Phillips"
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The purpose of this article has been made through a Marxist analysis of the US film "Captain Phillips" (PaulGreengrass, 2013), based on a true story. I have found how the evolution of capitalism in the West continuesto consolidate the belief reified in a historical and geographical superiority of the political and socioeconomicwestern models regarding Africa and Asia lowers models. At the same time, through categories like dialecticalmaterialism, criticism of diffusionist theory and application of cognitive mapping to large geopoliticalspaces located in most poor areas of the world, I have realized a remark about currently being articulatingthe political unconscious of working class in rich countries and the poor in poor countries, establishing arelationship between the ideological representation that takes an individual from his historical reality (ona scale that moves from local to global), and how he has developed a mental ability to escape of the responsibilityto make a critical review of what's happening around him in all areas. Finally, through physicalspace captured in the film, I have realized a materialist critique of globalized business process that takesplace through the carriage of goods, outlining spatial and cognitively limits of the mentality of our time, bothamong "winners"as among the "losers", based on the spatial movement of capital.
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Objectives: Elevated shame and dissociation are common in dissociative identity disorder (DID) and chronic posttraumatic stress disorder (PTSD) and are part of the constellation of symptoms defined as complex PTSD. Previous work examined the relationship between shame, dissociation, and complex PTSD and whether they are associated with intimate relationship anxiety, relationship depression, and fear of relationships. This study investigated these variables in traumatized clinical samples and a nonclinical community group.
Method: Participants were drawn from the DID (n = 20), conflict-related chronic PTSD (n = 65), and nonclinical (n = 125) populations and completed questionnaires assessing the variables of interest. A model examining the direct impact of shame and dissociation on relationship functioning, and their indirect effect via complex PTSD symptoms, was tested through path analysis.
Results: The DID sample reported significantly higher dissociation, shame, complex PTSD symptom severity, relationship anxiety, relationship depression, and fear of relationships than the other two samples. Support was found for the proposed model, with shame directly affecting relationship anxiety and fear of relationships, and pathological dissociation directly affecting relationship anxiety and relationship depression. The indirect effect of shame and dissociation via complex PTSD symptom severity was evident on all relationship variables.
Conclusion: Shame and pathological dissociation are important for not only the effect they have on the development of other complex PTSD symptoms, but also their direct and indirect effects on distress associated with relationships.
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Bakgrund: Sjuksköterskan har stor del i den nära patientvården och förväntas vara en god lyssnare genom sitt personcentrerade vårdgivande. Händelser som är traumatiska drabbar förutom den direkt berörda patienten även sjuksköterskan genom sekundär exponering. Syfte: Syftet med studien var att belysa förekomst av STS hos sjuksköterskor samt beskriva hur det påverkar vårdkvalitet och personcentrerad vård. Metod: Litteraturstudie med en översikt av relevanta artiklar i databaserna PubMed och CINAHL. Resultatet baseras på 14 artiklar som uppfyllde inklusionsoch kvalitetskrav. Resultat: Sjuksköterskan påverkas av STS på flera plan, både professionellt och personligt. Vårdkvaliteten blir lidande om STS påvisas. Den personcentrerade vården utgör grunden i sjuksköterskans yrkesutövande men om medvetenhet saknas för STS finns risken att sjuksköterskan påverkas så till den grad att hen väljer att sjukskriva sig och/eller byta arbetsplats. Slutsats: STS är ett relativt okänt begrepp och det kan vara svårt att se tecken på begynnande symtom. Sjuksköterskan kan utsättas för STS oberoende arbetsplats. Detta kan sänka effekten i yrkesutövandet genom personliga symtom som; irritabilitet, trötthet, minskad empati, depression, återupplevelser av tidigare upplevda traumatiska händelser med flera. Arbetsplatsens ledarskap inverkar på identifieringen av sjuksköterskans utveckling/hanterande av STS.
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There is an established relationship between salt intake and risk of high blood pressure (BP). High blood pressure (hypertension) is a risk factor for cardiovascular disease (CVD) and scientific evidence shows that a high salt intake can contribute to the development of elevated blood pressure. The Scientific Advisory Committee on Nutrition (SACN) recommend a target reduction in the average salt intake of the population to no more than 6g per day. This figure has been adopted by the UK government as the recommended maximum salt intake for adults and children aged 11 years and over. Following publication of the SACN report in 2003, the government began a programme of reformulation work with the food industry aimed at reducing the salt content of processed food products. Voluntary salt reduction targets were first set in 2006, and subsequently in 2009, 2011 and 2014, for a range of food categories that contribute the most to the population’s salt intakes. Population representative urinary sodium data were collected in England in 2005-06, 2008 (UK), 2011 and 2014. In the latest survey assessment, estimated salt intake of adults aged 19 to 64 years in England was assessed from 24-hour urinary sodium excretion of 689 adults, selected to be representative of this section of the population. Estimated salt intake was calculated using the equation 17.1mmol of sodium = 1g of salt and assumes all sodium was derived from salt. The data were validated as representing daily intake by checking completeness of the urine collections by the para-amino benzoic acid (PABA) method. Urine samples were collected over five months (May to September) in 2014, concurrently with a similar survey in Scotland. This report presents the results for the latest survey assessment (2014) and a new analysis of the trend in estimated salt intake over time. The trend analysis is based on data for urinary sodium excretion from this survey and previous sodium surveys (including data from the National Diet and Nutrition Survey Rolling Programme (NDNS RP) Years 1 to 5) carried out in England over the last ten years, between 2005-06 and 2014. This data has been adjusted to take account of biases resulting from differences between surveys in laboratory analytical methods used for sodium. The analysis provides a revised assessment of the trend in estimated salt intake over time. The trend analysis in this report supersedes the trend analysis published in the report of the 2011 England urinary sodium survey.
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Introdução: O stress condiciona o comportamento e desenvolvimento pessoal, podendo ter consequências preocupantes ao nível individual e organizacional. Os professores são uma classe reconhecida como estando sujeita a elevados níveis de stress, fator que prejudica a qualidade do ensino em geral. Objetivos: Avaliar a vulnerabilidade ao stress; identificar os principais fatores de stress e avaliar a correlação entre autoestima e stress, em professores do 1.º, 2.º e 3.º ciclos do ensino básico. Metodologia: Estudo correlacional, com uma amostra constituída por 60 professores do 1.º, 2.º e 3.º ciclos de escolaridade, de escolas do concelho de Leiria. Para a análise das variáveis em estudo foram aplicados: um questionário sociodemográfico; a Rosenberg Self-Esteem Scale (RSES); o Questionário de stress nos professores: ensino básico e secundário (QSPEBS) e a Escala de vulnerabilidade ao stress (23 QVS). Resultados: O estudo revela que 65% dos professores percecionam a profissão como stressante e que 30% são vulneráveis ao stress. O principal fator de stress identificado foi comportamentos inadequados/indisciplina dos alunos. Verificou-se uma correlação negativa entre a autoestima e a vulnerabilidade ao stress dos professores. Conclusão: Conclui-se que, quanto mais elevada é a auto-estima, menor é a vulnerabilidade dos professores ao stress e que, apesar de não se registarem níveis significativos de vulnerabilidade ao stress na população docente, a maioria dos professores perceciona a sua atividade profissional como geradora de elevados níveis de stress, sendo os comportamentos inadequados/indisciplina dos alunos o fator que mais contribui para o stress nos docentes. / Introduction: Stress affects behavior and personal development, and may have severe consequences either at the individual or organizational level. Teachers are identified as a class exposed to high levels of stress, factor that affects the quality of education in general. Objectives: To assess stress vulnerability; identify key stressors and assess the correlation between self-esteem and stress in primary and secondary school teachers. Methodology: A sociodemographic questionnaire and three self-report measures were administered to a sample of 60 primary and secondary teachers from Leiria district: the Rosenberg Self-Esteem Scale (RSES); a teachers stress questionnaire for primary, secondary and high school (QSPEBS) and a scale to access stress vulnerability (23 QVS). Results: The study reveals that 65% of teachers perceive the profession as stressful and that 30% are vulnerable to stress. The main stressor identified is inappropriate/disruptive behavior of students. There is a negative correlation between self-esteem and vulnerability to stress of teachers. Conclusion: We conclude that a higher self-esteem leads to less stress vulnerability in teachers and that, despite the non-significant level of vulnerability determined in this study, most teachers perceive their activity as stressful, being inappropriate/disruptive behavior of students the factor that most contributes for that.
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Behavior of granular material subjected to repeated load triaxial compression tests is characterized by a model based on rate process theory. Starting with the Arrhenius equation from chemical kinetics, the relationship of temperature, shear stress, normal stress and volume change to deformation rate is developed. The proposed model equation includes these factors as a product of exponential terms. An empirical relationship between deformation and the cube root of the number of stress applications at constant temperature and normal stress is combined with the rate equation to yield an integrated relationship of temperature, deviator stress, confining pressure and number of deviator stress applications to axial strain. The experimental program consists of 64 repeated load triaxial compression tests, 52 on untreated crushed stone and 12 on the same crushed stone material treated with 4% asphalt cement. Results were analyzed with multiple linear regression techniques and show substantial agreement with the model equations. Experimental results fit the rate equation somewhat better than the integrated equation when all variable quantities are considered. The coefficient of shear temperature gives the activation enthalpy, which is about 4.7 kilocalories/mole for untreated material and 39.4 kilocalories/mole for asphalt-treated material. This indicates the activation enthalpy is about that of the pore fluid. The proportionality coefficient of deviator stress may be used to measure flow unit volume. The volumes thus determined for untreated and asphalt-treated material are not substantially different. This may be coincidental since comparison with flow unit volumes reported by others indicates flow unit volume is related to gradation of untreated material. The flow unit volume of asphalt-treated material may relate to asphalt cement content. The proposed model equations provide a more rational basis for further studies of factors affecting deformation of granular materials under stress similar to that in pavement subjected to transient traffic loads.
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Apesar de todos nós nos esquecermos, é comum atribuir-se os lapsos de memória às pessoas com idades avançadas. A evidência científica tem, no entanto, demonstrado que o esquecimento advém de uma multiplicidade de factores, como por exemplo, o excesso de trabalho, falta de descanso, entre outros. Neste estudo pretende-se saber se existe associação entre a tríade conceptual ansiedade, stress e depressão e os lapsos de memória, numa população em idade activa e com habilitações académicas de nível superior. A amostra é constituída por 68 professores que exercem a sua actividade profissional na Escola E.B. 2,3 de Cantanhede. A recolha dos dados foi efectuada recorrendo a: um questionário elaborado por nós, constituído por questões abertas e fechadas, uma Escala de Ansiedade, Depressão e Stress (EADS-21) e um Questionário de lapsos de memória (QLM). As análises estatísticas dos questionários foram efectuadas recorrendo ao programa informático SPSS (versão 15). As análises tiveram com objectivo final a testagem das hipóteses e tomaram em consideração a natureza métrica das variáveis. / In spite of all of we forget ourselves, it is common the lapses of memory are attributed to the persons with advanced ages. The scientific evidence has, however, when that the oblivion results from a multiplicity of factors was demonstrated, I eat for example, the excess of work, rest lack, between others. In this study one intends to know if there is association between the conceptual triad anxiety, stress and depression and the lapses of memory, in a population in active age and with academic competences of superior level. The sample is constituted by 68 teachers who practice his professional activity in the School E.B. 2,3 of Cantanhede. The gathering of the data was effectuated resorting to: a questionnaire prepared by us, constituted by questions open and shut, a Scale of Anxiety, Depression and Stress (EADS-21) and a Questionnaire of lapses of memory (QLM). The statistical analyses of the questionnaires were effectuated when there is resorting to the program informatics SPSS (version 15). The analyses had with final objective the testate of the hypotheses and took in consideration the metric nature of the variables.
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PURPOSE: The use of information and communication technology (ICT) is common in modern working life. ICT demands may give rise to experience of work-related stress. Knowledge about ICT demands in relation to other types of work-related stress and to self-rated health is limited. Consequently, the aim of this study was to examine the association between ICT demands and two types of work-related stress [job strain and effort-reward imbalance (ERI)] and to evaluate the association between these work-related stress measures and self-rated health, in general and in different SES strata. METHODS: This study is based on cross-sectional data from the Swedish Longitudinal Occupational Survey of Health collected in 2014, from 14,873 gainfully employed people. ICT demands, job strain, ERI and self-rated health were analysed as the main measures. Sex, age, SES, lifestyle factors and BMI were used as covariates. RESULTS: ICT demands correlated significantly with the dimensions of the job strain and ERI models, especially with the demands (r = 0.42; p < 0.01) and effort (r = 0.51; p < 0.01) dimensions. ICT demands were associated with suboptimal self-rated health, also after adjustment for age, sex, SES, lifestyle and BMI (OR 1.49 [95 % CI 1.36-1.63]), but job strain (OR 1.93 [95 % CI 1.74-2.14) and ERI (OR 2.15 [95 % CI 1.95-2.35]) showed somewhat stronger associations with suboptimal self-rated health. CONCLUSION: ICT demands are common among people with intermediate and high SES and associated with job strain, ERI and suboptimal self-rated health. ICT demands should thus be acknowledged as a potential stressor of work-related stress in modern working life.
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Mestrado em Segurança e Higiene no Trabalho