48 resultados para alfa-Fetoproteína


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The Nursing Process (NP) is considered as the dynamics of the systemized and inter-related actions of human care. We believe that the nursing manager, as the representative of all the nursing care provided in the hospital setting, is an important agent for the implementation of institutional policies, such as the NP, in the service. However, there is little information in the literature about the NP in the perspective of the nurse manager. The objective of this study was to analyze the viability of the Nursing Process in the hospital context based on the attitudes of the nurse managers toward the Process. We conducted a descriptive-exploratory research study, of quantitative approach, with a population of 45 nurse managers that worked in the state hospitals located in Natal, RN and in the university hospitals of the UFRN. Two instruments were used for the collection of data: a nursing process questionnaire, constructed for use in this study, and the scale for the measurement of the attitudes titled Positions on the Nursing Process. The population is predominantly feminine (91,0%) and have relative nursing practice experience (Mean=17,6 years). However, they have little experience in management (Mean=8,6 years). They express little knowledge of the PE nursing terms and little experience with the Process. They have a positive atitude toward the NP (Mean = 110,9); are favorable to its developement in the service (86,7%); 48,9% indicated little possibility of institutionalization in the service and 37,8% indicated large possibility. The Spearman test for association between the variables of attitude about the NP and the possibility of its institutionalization demonstrated a weak negative association in the total individual scores of the attitudes (-,316) as in the 20 itens of the instrument, with coefficients varying from 0,014 to 0,464. Factorial analysis of the instrument identified three underlying factors to the attitudes of the managers in this study: relevance, operationalization and collaboration, with Cronbach Alpha coeficients of 0,955, 0,844 and 0,807, respectively, and 0,956 for the whole instrument, indicating that the scale and its factorial subscales have internal consistency. We conclude that there is a weak tendency for the managers with a favorable attitude to have a negative perception about the possibility of institutionalization of the NP in the service. The favorable position does not appear to be sufficient for the viability of this methodology in the hospital sector, results that is worrisome for nursing. This situation suggests that the difficulties with the institution of the NP in the hospitals may be related to other factors, including the organizational conditions. We believe that the institucionalization of the NP in a servisse where it is not known and not practiced, constitutes the introduction of an innovative work technology that involves many demands, among them the adherence of the persons to the proposed innovation. This demands time and the institutional adjustments and the human resources necessary. In this process, the involvement of the health professional of the institution is necessary. This situation brings to light the discussions of professional autonomy, the action limits and perspectives, the redefinition of roles, delimiation (or consensus) of the objects of study and of the work processes, among others.

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Exploratory descriptive study, prospective with quantitative approach, performed in the nefrology outpatient service from the Onofre Lopes University Hospital (HUOL), Natal/RN, aiming to identify aspects that concern Quality of Life (QOL) on transplanted and hemodialysis patients, as measured by WHOQOL-bref and describe the aspects that differentiate QL between the two groups as measured by the same instrument. The population was of 62 renal patients in hemodialysis and 58 transplantd, with data collected from february to march 2006. The instrument used was WHOQOL-bref, translated to and validated for Portuguese by the multicentric group of the World Health Organization (WHO) in Brazil. The results show predominance of the masculine gender both in the post-transplant group (55,17%), as well as in the hemodialysis group (51,61%); the age strip of 28 to 43 prevailed, among which were 53,45% transplanted and 48,99% hemodialysis patients; 79,93% of the hemodialysis patients and 62,07% of the transplanted were provenient from ouside the capital of the state; from the hemodialysis population, 59,68% were married, while among the transplanted 48,28% were single; 58,06% of the hemodialisys patients had 1 to 3 children, while the majority of the transplanted, 44,83%, had no children; regarding scholarity level on both groups, there was a predominance of incomplete fundamental school, representing 62,9% of the hemodialysis patients and 46,6% of the transplanted; regarding work status, 98,39% of those in hemodialysis informed not to be working, and the same applied to the transplanted, with 75,86%; regarding treatment time, most patients of both populations were in the 1- to 4-year interval, of which were 62,9% of the hemodialisys patients and 53,45% of the transplanted. The analysis of WHOQOL-bref reliability through Crobach s Alpha coefficient had a value of 0,8816, demonstrating good internal consistency for the instrument. Regarding description of QOL tests, the average scores of the post-transplant were (Q-1) 18,14 e (Q-2) 18,69, and 12,3 (Q-1) and 11,29 (Q-2) for the group in hemodialisys. Regarding the aspects that differentiate QOL on the two groups observed through average scores from the Domains: Physical, 15,91 for the post-transplant group and 12,71 for the hemodialisys group; Psychological, 16,75 for the post-transplant group and 14,84 for the hemodialisys group; Social Relations, 17,79 on the post-transplant group and 16,58 on the hemodialisys group; Environment, 14,16 on the post-transplant group and 12,38 on the hemodialisys group. On every evaluated item, the post-transplant group achieved higher scores when compared to the hemodialisys group. The diference in QOL for both populations was significant on all items evaluated with a p<0,005

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Empathy is a basic facilitating element of the therapeutic helping relationship and the humanization process in health care. The objectives of this study were to identify the empathy level of health professionals working in the obstetrical sector of a university hospital recognized for its humanistic care and the perceptions of the women under their care regarding the empathic behavior shown by these professionals during hospitalization. We conducted a quanti/qualitative study with 47 health professionals that worked in the obstetrical sector (13 obstetricians, 12 nurses, 22 nurse technicians) and an intentional sample of 101 women that received cared from these professionals during the study period. We collected data by means of the Jefferson Empathy Scale for Health Professioals (JEPS-HR) and the Patient´s Perception of Health Professional Empathy (PPHPE), and two additional open questions designed to obtain the subjective opinion about the empathic behavior during the care. We utilized thematic analysis for the data obtained through the open questions and descriptive and inferential statistics for the quantitative data. We identified five thematic categories that represent the aspects valued by the professionals in their relationship with the women under their care: emotional involvement, communication, warm environment, integral vision and technical/scientific knowledge. The mean score on the JEPS-HR reported for the health professionals was 120,40, being that the maximum possible was 140.The Cronbach Alpha for the JEPS-HR was 0,83, indicating an acceptable level of reliability for this population. We consider therefore, that these professionals presented an acceptable empathy level when compared to other populations observed with the JEPS-HR. The results also indicated that women had statistically significant (p ≤ 0,05) higher scores than men and that professionals with higher working hours tended to have lower scores in the empathy scale (r = -0,288; p ≤ 0,05). The analysis of the subjective responses of the women indicated that they were satisfied with the humanistic care provided by the professionals but they also point out the existence of some power relationships. There were no significant differences in the empathy level of the medical or nursing team perceived by the women who registered means of 41,90 and 41,20 respectively on the PPHPE. In view of these results and considering the relevance of the element of empathy for care based on humanistic values, we reiterate the importance of further in-service training for the health team of the hospital in focus, on the topics of empathy and global aspects of humanized care for the implementation of its mission

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This master's thesis aims to ascertain how the Stakeholders interactions influence the adoption of green marketing strategies from the perspective of the Alpha Company, a furniture industry located in Rio Grande do Norte, Brazil. The methodology has a qualitative approach and uses the exploratorydescriptive case study method as model of formal and systematic study. Following the theoretical and conceptual propositions of Polonsky (1995), Michell, Angle and Wood (1997) and Frooman (1999) as a reference base. This study identifies and assesses the importance degree of the relevant stakeholders, shows their expectations and needs and describes the tactics used by the company for the implementation of green marketing strategies. The study describes the reality of a furniture industry in Rio Grande do Norte, and shows his philosophy and background; identifies present stakeholders that influence the decision process of the company and also, analyzes the degree of importance of each group showing their needs and expectations and, finally, it states the changes in the organization with the implementation of green marketing strategies. The results it s concluded that stakeholders are taken into consideration in the adoption of green marketing strategies, even without a proper strategic perception from the company, an imperative to advance towards the adoption of the green marketing philosophy. This case study explores knowledge that may be used and suited to small companies that act in the strategic segment-trend of green marketing

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The increasing demand for high performance wireless communication systems has shown the inefficiency of the current model of fixed allocation of the radio spectrum. In this context, cognitive radio appears as a more efficient alternative, by providing opportunistic spectrum access, with the maximum bandwidth possible. To ensure these requirements, it is necessary that the transmitter identify opportunities for transmission and the receiver recognizes the parameters defined for the communication signal. The techniques that use cyclostationary analysis can be applied to problems in either spectrum sensing and modulation classification, even in low signal-to-noise ratio (SNR) environments. However, despite the robustness, one of the main disadvantages of cyclostationarity is the high computational cost for calculating its functions. This work proposes efficient architectures for obtaining cyclostationary features to be employed in either spectrum sensing and automatic modulation classification (AMC). In the context of spectrum sensing, a parallelized algorithm for extracting cyclostationary features of communication signals is presented. The performance of this features extractor parallelization is evaluated by speedup and parallel eficiency metrics. The architecture for spectrum sensing is analyzed for several configuration of false alarm probability, SNR levels and observation time for BPSK and QPSK modulations. In the context of AMC, the reduced alpha-profile is proposed as as a cyclostationary signature calculated for a reduced cyclic frequencies set. This signature is validated by a modulation classification architecture based on pattern matching. The architecture for AMC is investigated for correct classification rates of AM, BPSK, QPSK, MSK and FSK modulations, considering several scenarios of observation length and SNR levels. The numerical results of performance obtained in this work show the eficiency of the proposed architectures

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In the present work are established initially the fundamental relationships of thermodynamics that govern the equilibrium between phases, the models used for the description of the behavior non ideal of the liquid and vapor phases in conditions of low pressures. This work seeks the determination of vapor-liquid equilibrium (VLE) data for a series of multicomponents mixtures of saturated aliphatic hydrocarbons, prepared synthetically starting from substances with analytical degree and the development of a new dynamic cell with circulation of the vapor phase. The apparatus and experimental procedures developed are described and applied for the determination of VLE data. VLE isobarics data were obtained through a Fischer s ebulliometer of circulation of both phases, for the systems pentane + dodecane, heptane + dodecane and decane + dodecane. Using the two new dynamic cells especially projected, of easy operation and low cost, with circulation of the vapor phase, data for the systems heptane + decane + dodecane, acetone + water, tween 20 + dodecane, phenol + water and distillation curves of a gasoline without addictive were measured. Compositions of the equilibrium phases were found by densimetry, chromatography, and total organic carbon analyzer. Calibration curves of density versus composition were prepared from synthetic mixtures and the behavior excess volumes were evaluated. The VLE data obtained experimentally for the hydrocarbon and aqueous systems were submitted to the test of thermodynamic consistency, as well as the obtained from the literature data for another binary systems, mainly in the bank DDB (Dortmund Data Bank), where the Gibbs-Duhem equation is used obtaining a satisfactory data base. The results of the thermodynamic consistency tests for the binary and ternary systems were evaluated in terms of deviations for applications such as model development. Later, those groups of data (tested and approved) were used in the KijPoly program for the determination of the binary kij parameters of the cubic equations of state original Peng-Robinson and with the expanded alpha function. These obtained parameters can be applied for simulation of the reservoirs petroleum conditions and of the several distillation processes found in the petrochemistry industry, through simulators. The two designed dynamic cells used equipments of national technology for the determination of VLE data were well succeed, demonstrating efficiency and low cost. Multicomponents systems, mixtures of components of different molecular weights and also diluted solutions may be studied in these developed VLE cells

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The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

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In the present work are established initially the fundamental relationships of thermodynamics that govern the equilibrium between phases, the models used for the description of the behavior non ideal of the liquid and vapor phases in conditions of low pressures. This work seeks the determination of vapor-liquid equilibrium (VLE) data for a series of multicomponents mixtures of saturated aliphatic hydrocarbons, prepared synthetically starting from substances with analytical degree and the development of a new dynamic cell with circulation of the vapor phase. The apparatus and experimental procedures developed are described and applied for the determination of VLE data. VLE isobarics data were obtained through a Fischer's ebulliometer of circulation of both phases, for the systems pentane + dodecane, heptane + dodecane and decane + dodecane. Using the two new dynamic cells especially projected, of easy operation and low cost, with circulation of the vapor phase, data for the systems heptane + decane + dodecane, acetone + water, tween 20 + dodecane, phenol + water and distillation curves of a gasoline without addictive were measured. Compositions of the equilibrium phases were found by densimetry, chromatography, and total organic carbon analyzer. Calibration curves of density versus composition were prepared from synthetic mixtures and the behavior excess volumes were evaluated. The VLE data obtained experimentally for the hydrocarbon and aqueous systems were submitted to the test of thermodynamic consistency, as well as the obtained from the literature data for another binary systems, mainly in the bank DDB (Dortmund Data Bank), where the Gibbs-Duhem equation is used obtaining a satisfactory data base. The results of the thermodynamic consistency tests for the binary and ternary systems were evaluated in terms of deviations for applications such as model development. Later, those groups of data (tested and approved) were used in the KijPoly program for the determination of the binary kij parameters of the cubic equations of state original Peng-Robinson and with the expanded alpha function. These obtained parameters can be applied for simulation of the reservoirs petroleum conditions and of the several distillation processes found in the petrochemistry industry, through simulators. The two designed dynamic cells used equipments of national technology for the determination Humberto Neves Maia de Oliveira Tese de Doutorado PPGEQ/PRH-ANP 14/UFRN of VLE data were well succeed, demonstrating efficiency and low cost. Multicomponents systems, mixtures of components of different molecular weights and also diluted solutions may be studied in these developed VLE cells

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Introduction: The human gestation period is 40 weeks. This is the essential time for maternal psychosocial adaptation, in which there is the intense transformation of a life without offspring into a life with one or more children. The Pregnancy Self-Evaluation Questionnaire (PSEQ) has 79 items, subdivided into seven subcategories: acceptance of pregnancy, identification with the maternal role, well-being of mother and baby, preparing for labor, control in labor, relationship with the mother and the relationship with the partner. Objective: To translate and cross-culturally adapt the instrument PSEQ to be used with Brazilian women. Methods: It is a cross-sectional observational study. We followed some methodological steps to achieve the cross-cultural adaptation of this measuring instrument. They are: translation, synthesis, back translation, analysis of the committee of specialists and pre-test. Another questionnaire was applied to characterize the socio-demographic and clinical status of the pregnant women (n = 36). The descriptive statistics was gotten through the average, standard deviation (SD), absolute and relative frequency. The statistical test used for the analysis of the internal consistency was Cronbach's alpha coefficient, using SPSS version 17.0. Results: The volunteers had low socioeconomic status, average age of 25.1 years (± 5.52), and average gestational age of 25.9 weeks (± 8.11). 58.3% of these volunteers had not planned their current pregnancy. The pretest showed that 75% of pregnant women found the questionnaire easy to understand. There was an average of 76.9 (± 3.23) answered items among the participants. Regarding the instrument PSEQ, the identification with the maternal role was the subcategory which showed the highest average 24.8 (± 5.6), while the relationship with the mother had the lowest average 15.4 (± 7.7). The internal consistency ranged from 0.52-0.89. Conclusion: The translation and cross-cultural adaptation of the PSEQ to Portuguese language were carried out with methodological rigor and can be considered an instrument with good internal consistency

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Activation of the kynurenine (KYN) pathway (KP) by modulators of immune system has been observed during several neurological diseases. Here we assessed the association of chemo-/cytokine levels with the concentration of KP metabolites in cerebrospinal fluid (CSF) and plasma samples from patients with bacterial meningitis (BM). All samples were collected from 42 patients diagnosed with acute bacterial meningitis (ABM), aseptic meningitis, tuberculous meningitis and patients without infection neurological disorders. CSF and plasma concentration of metabolites from the KP was assessed by high pressure liquid chromatography (HPLC) and cytokines and chemokines by Bio-plex 200 suspension array system. Concentrations of the KP metabolites KYN and kynurenic acid (KYNA) were significantly higher in CSF of patients with ABM compared to other groups. Tryptophan (TRP), anthranilic acid (AA), 3-hydroxykynurenine (3HK) and 3-hydroxyanthranilic acid (3HAA) did not show statistical significance, although some of them presented a good accumulation during ABM. The expression of TNF-alpha, IL-6, IL-1beta, IFN-gamma, IL-10, IL-1 receptor antagonist (IL-1Ra), MIP-1alpha, MIP-1beta, MCP-1 and G-CSF was about 100-fold higher in CSF from ABM patients than other infected groups. In all CSF and plasma samples, the concentration of IL-2, IL-12(p70), IL-4, IL-8 and GM-CSF was not significant. ABM still showed significant concentrations of IL-6, IL-10, IL-1Ra and MCP-1 in plasma samples. Based on the comparison of KP metabolites concentrations between plasma and CSF samples we conclude that the activation of the tryptophan pathway upon BM occurs within the brain. This increase in KP metabolites is most due to activation of the KP by molecules as IFN-gamma and TNF-alpha in response to infection.

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Gluconacetobacter diazotrophicus é uma alfa-proteobactéria Gram-negativa, tolerante a meios ácidos, fixadora de nitrogênio atmosférico e foi a primeira bactéria diazotrófica endofítica isolada da cana-de-açúcar. Por sua vez, Gluconobacter oxydans, também alfa-proteobactéria Gram-negativa, possui a capacidade de oxidar incompletamente alcoóis e carboidratos. Ambas de interesse biotecnológico e industrial, essas bactérias tiveram seus genomas seqüenciados completamente em 2007. Desta forma, foi de interesse desse trabalho analisar e comparar os genes de reparo do DNA devido sua importância na manutenção da integridade genômica. Sendo assim, as vias de reparo presentes nos dois organismos foram identificadas, utilizando como base uma terceira alfa-proteobactéria, a Caulobacter crescentus, cujos genes de reparo foram descritos por um trabalho anterior e também os genes bem estabelecidos para o reparo do DNA em Escherichia coli. Para esse estudo, um banco de dados contendo ortólogos para os genes de reparo de DNA encontrados nos organismos foi criado e análises comparativas por similaridade usando o pacote Blast e o software Clustal foram feitas. Este estudo demonstrou que as principais vias de reparo ao DNA reparos por excisão, reparo direto, reparo recombinacional e reparo pelo sistema SOS estão presentes nos organismos analisados, demonstrando, na maioria das vezes, boa similaridade com E. coli. Interessantemente, foram encontradas duplicações gênicas nos quais uma das cópias estava presente no cromossomo e a outra, no plasmídeo, como no caso de UvrD, DnaE e Ssb, possivelmente caracterizando eventos de transferência lateral. Por fim, uma grande novidade foi a identificação de ortólogos para RecB em G. diazotrophicus e G. oxydans e de ortólogos duplicados de RecD em G. diazotrophicus. Até o momento, não havia sido relatada a presença de membros da via de iniciação RecBCD do reparo recombinacional em alfaproteobactérias

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Periodontal disease is an infection initiated by oral periodontal pathogens that trigger an immune response culminating in tissue destruction. This destruction is mediated by the host by inducing the production and activation of lytic enzymes, cytokines and the stimulation of osteoclastogenesis. The aim of this study was to compare the immunohistochemical expression of factors involved in bone resorption, RANKL (Ligand Receptor Activator of Nuclear Factor kappa B), OPG (Osteoprotegerin) and TNF-α (tumor necrosis factor alpha) between the gingival healthy, gingivitis and chronic periodontitis and correlate them with clinical parameters. The sample consisted of 83 cases and 12 clinically healthy gums, 42 gingivitis and 29 periodontitis, from 74 adolescent and adult patients with a mean age of 35 years, without systemic changes and non-smokers, predominantly female and race brown. There was no statistically significant difference for the expression of anti-RANKL (p = 0.581) and RANKL / OPG ratio (p = 0.334) when comparing the three conditions, but the anti-OPG and anti-TNF-α showed statistically significant between the types of injury (p = 0.001 and p <0.001, respectively), showing greatest expression in periodontitis. In cases of periodontitis, the variable clinical attachment loss (PIC) was statistically significant and positive correlation, respectively, with immunostaining of anti-RANKL (p = 0.002, p = 0.001 and r = 0.642), anti-OPG (p = 0.018, p = 0.014 and r = 0.451), anti-TNF-α (p = 0.032, p = 0.014 and r = 0.453) and the percentage ratio of RANKL / OPG (p = 0.018, p = 0.002 and r = 0.544). The tooth mobility (MB) showed a statistically significant difference only with immunohistochemical anti-RANKL (p = 0.026), and probing depth (PD) was positively correlated with anti-RANKL (p = 0.028 and r = 0.409), both in cases of periodontitis. Only in cases of gingivitis TNF-α was positively correlated with RANKL (p = 0.012 and r = 0.384) and the RANKL / OPG ratio (p = 0.027 and r = 0.341). Given these results, we conclude that the greatest expression of TNF-α in periodontitis demonstrates a relationship with the progression and severity of periodontal disease and the correlation between all antibodies and clinical attachment loss demonstrates their involvement in periodontal bone resorption

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Lucid dreaming (LD) is a mental state in which the subject is aware of being dreaming while dreaming. The prevalence of LD among Europeans, North Americans and Asians is quite variable (between 26 and 92%) (Stepansky et al., 1998; Schredl & Erlacher, 2011; Yu, 2008); in Latin Americans it is yet to be investigated. Furthermore, the neural bases of LD remain controversial. Different studies have observed that LD presents power increases in the alpha frequency band (Tyson et al., 1984), in beta oscillations recorded from the parietal cortex (Holzinger et al., 2006) and in gamma rhythm recorded from the frontal cortex (Voss et al., 2009), in comparison with non-lucid dreaming. In this thesis we report epidemiological and neurophysiological investigations of LD. To investigate the epidemiology of LD (Study 1), we developed an online questionnaire about dreams that was answered by 3,427 volunteers. In this sample, 56% were women, 24% were men and 20% did not inform their gender (the median age was 25 years). A total of 76.5% of the subjects reported recalling dreams at least once a week, and about two-thirds of them reported dreaming always in the first person, i.e. when the dreamer observes the dream from within itself, not as another dream character. Dream reports typically depicted actions (93.3%), known people (92.9%), sounds/voices (78.5%), and colored images (76.3%). The oneiric content was related to plans for upcoming days (37.8%), and memories of the previous day (13.8%). Nightmares were characterized by general anxiety/fear (65.5%), feeling of being chased (48.5%), and non-painful unpleasant sensations (47.6%). With regard to LD, 77.2% of the subjects reported having experienced LD at least once in their lifetime (44.9% reported up to 10 episodes ever). LD frequency was weakly correlated with dream recall frequency (r = 0.20, p <0.001) and was higher in men (χ2=10.2, p=0.001). The control of LD was rare (29.7%) and inversely correlated with LD duration (r=-0.38, p <0.001), which is usually short: to 48.5% of the subjects, LD takes less than 1 minute. LD occurrence is mainly associated with having sleep without a fixed time to wake up (38.3%), which increases the chance of having REM sleep (REMS). LD is also associated with stress (30.1%), which increases REMS transitions into wakefulness. Overall, the data suggest that dreams and nightmares can be evolutionarily understood as a simulation of the common situations that happen in life, and that are related to our social, psychological and biological integrity. The results also indicate that LD is a relatively common experience (but not recurrent), often elusive and difficult to control, suggesting that LD is an incomplete stationary stage (or phase transition) between REMS and wake state. Moreover, despite the variability of LD prevalence among North Americans, Europeans and Asians, our data from Latin Americans strengthens the notion that LD is a general phenomenon of the human species. To further investigate the neural bases of LD (Study 2), we performed sleep recordings of 32 non-frequent lucid dreamers (sample 1) and 6 frequent lucid dreamers (sample 2). In sample 1, we applied two cognitive-behavioral techniques to induce LD: presleep LD suggestion (n=8) and light pulses applied during REMS (n=8); in a control group we made no attempt to influence dreaming (n=16). The results indicate that it is quite difficult but still possible to induce LD, since we could induce LD in a single subject, using the suggestion technique. EEG signals from this one subject exhibited alpha (7-14 Hz) bursts prior to LD. These bursts were brief (about 3s), without significant change in muscle tone, and independent of the presence of rapid eye movements. No such bursts were observed in the remaining 31 subjects. In addition, LD exhibited significantly higher occipital alpha and right temporo-parietal gamma (30-50 Hz) power, in comparison with non-lucid REMS. In sample 2, LD presented increased frontal high-gamma (50-100 Hz) power on average, in comparison with non-lucid REMS; however, this was not consistent across all subjects, being a clear phenomenon in just one subject. We also observed that four of these volunteers showed an increase in alpha rhythm power over the occipital region, immediately before or during LD. Altogether, our preliminary results suggest that LD presents neurophysiological characteristics that make it different from both waking and the typical REMS. To the extent that the right temporo-parietal and frontal regions are related to the formation of selfconsciousness and body internal image, we suggest that an increased activity in these regions during sleep may be the neurobiological mechanism underlying LD. The alpha rhythm bursts, as well as the alpha power increase over the occipital region, may represent micro-arousals, which facilitate the contact of the brain during sleep with the external environment, favoring the occurrence of LD. This also strengthens the notion that LD is an intermediary state between sleep and wakefulness

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O estado vibracional (EV) é descrito como uma sensação de vibração intensa por todo o corpo, em que o sujeito se mantém num estado de relaxamento psicofisiológico que pode ser gerado de forma espontânea ou autoinduzida. Pessoas que aplicam esta técnica relatam alterações do estado mental e emocional, tais como: relaxamento, disposição, limpidez de pensamento, equilíbrio emocional, melhoria do raciocínio, bemestar, entre outros. Estas são, entretanto observações subjetivas, sendo a mensuração deste fenômeno uma lacuna e um desafio para a ciência. O objetivo desta pesquisa é explorar sistematicamente o estado vibracional no âmbito da neurociência. Desta forma, medidas eletroencefalográficas (EEG) foram utilizadas para observar se a sensação subjetiva de EV é acompanhada por mudanças na atividade elétrica cerebral. Além disso, para avaliar se o EV provoca algum efeito positivo em funções cognitivas como atenção e memória, foi utilizado um teste de reconhecimento de palavras antes e depois da aplicação da técnica de EV. Foram também aplicados questionários de dados gerais socioeconômicos e de saúde, do perfil de estados de humor, de qualidade do sono, além de inventários psicológicos. O foco inicial do trabalho foi a análise estatística dos dados de EEG, ficando as outras análises para uma etapa posterior. Dois grupos de voluntários foram analisados, o primeiro formado por 14 sujeitos que praticam a técnica de EV há pelo menos 10 anos (Grupo Experiente - GEXP), e o segundo formado por 11 sujeitos que nunca haviam realizado a técnica (Grupo Controle - GCONT). O GCONT obteve instruções sobre a técnica de EV antes dos experimentos. Foram realizadas análises estatísticas dos registros eletroencefalográficos, para comparar os grupos, em quatro condições: Basal, Relaxamento, Não-EV (período em que o sujeito está engajado na tarefa, mas ainda não percebe o EV) e EV (período em que o sujeito percebe o EV). Uma vez que os sujeitos do GCONT relataram não ter conseguido atingir a condição de EV propriamente, a comparação entre grupos foi feita apenas nas três condições, Basal, Relaxamento e Não-EV. Para isso, foi usado o teste de Mann-Whitney U com um limiar estatístico de p<0,05. De forma geral, o GEXP apresentou maior potência na banda de frequência alfa 2 (9,5-11,0 Hz) em todas as condições. Durante o período Não-EV, o GEXP também apresentou uma maior potência na banda de frequência alfa 3 (11,5-13,0 Hz) na região temporal esquerda, e gama 1 (30,5-55,0 Hz) e gama 2 (65,0-80,0 Hz) em regiões central, parietal e temporal esquerda, mas menor potência na banda de frequência teta 1 (3,5 - 5,0 Hz), em regiões centro-parietais. Para a análise estatística intragrupo, entre as condições, utilizou-se o teste estatístico Wilcoxon pareado. Observaram-se diferenças significativas (p<0,005), principalmente em regiões centrais, em teta 1 (3,5-5,0 Hz), sendo maior no Relaxamento, quando comparado com as condições Basal e Não-EV, no GCONT, e com o Não-EV e EV, no GEXP. No GEXP, a potência de gama 1 (30,5-55,0 Hz) e gama 2 (65,0-80,0 Hz) foi difusamente maior durante o EV, se comparado às outras três condições. Para o GCONT, apenas a condição Basal apresentou maior potência de gama 1 (30,5-55,0 Hz) e gama 2 (65,0- 80,0 Hz), se comparado com o Relaxamento. O aumento de teta 1 no Relaxamento, principalmente no GCONT, pode estar associado a uma maior sonolência deste grupo durante esta condição. Já o aumento de alfa 2 durante o Não-EV e o EV, pode estar associado com processos de atenção e cognição (DOLPPERMAYR et al., 2002; FELL et al., 2010; KLIMESCH et al., 1999; RAY E COLE, 1985). Por outro lado, o aumento da potência de gama em sujeitos experientes na técnica de EV encontrado aqui e em trabalhos anteriores, em meditadores experientes (FELL et al., 2010; LEHMANN et al., 2001; LUTZ et al., 2004), poderia estar associado a alterações nos processos mentais e cognitivos destes praticantes, tais como atenção, memória operacional, aprendizagem e percepção consciente embora, análises adicionais devam ser realizadas para excluir a possibilidade de interferência de artefatos musculares nos dados de EEG. Estes resultados suscitam a hipótese de que no engajamento da tarefa do EV e durante o EV, os sujeitos do GEXP conseguem manter-se em um estado de alerta, porém com maior nível de relaxamento e concentração. Uma inspeção mais detalhada dos dados, além de outros experimentos com diferentes protocolos, um maior número de sujeitos e pesquisas longitudinais são necessários para que testar esta hipótese

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The study of the motivation to practice physical activities is relevant once through this it is possible to develop intervention strategies for sedentary population. In this way, the present dissertation aimed to adapt and validate for the Brazilian context the Motives for Physical Activity Measure Revised (MPAM-R). It was investigated yet the relation of some socio-demographic variables (age, gender, Body Mass Index - BMI, types of physical activity; way to practice and time of practice) and the participants means in the motives studied. The physical activity (PA) is defined as any bodily movement produced by skeletal muscles resulting in energy expenditure above the basal level. However, in the present study it was considered motivation for two types of PA: the physical exercises and sports. The Self-Determination Theory (SDT) underlay this research, once it has been used in the sportive context, beyond the facto of it was used as theoretical base to the development of MPAM-R. To attain the proposed goals, it was accomplished translations to Portuguese of the original English scale. Next, was carried out the semantic analysis and the judge analysis. For the empirical analysis of items, participated 309 practitioner of PA, classified in physical exercises practitioners and sports practitioners, with ages between 16 and 74 years, distributed equally by sex. They answered the final version in Portuguese of the MPAM-R and socio-demographic questions. The data was collected in Natal/RN, where the researcher approached people in some places where the PA is practiced, following she communicated that their involvement will be spontaneous and their responses will be confidential. The obtained results pointed the confirmation of the existence of five factors in the final version of the instrument, that was composed by 26 items that presented the following statistics indexes: x² (289) = 757.75, p < 0.000, x²/DF = 2.62, with GFI of 0.83, AGFI of 0.80 and RMSEA of 0.07. The reliability (Cronbach Alpha) of the complete instrument was 0.90, and the indexes of each factor were considered satisfactory too: Enjoyment (α = 0.88), Health (α = 0.84), Appearance (α = 0.79), Competence (α = 0.85) and Social (α = 0.75). It was observed that, in general, the main motive presented by the participants to practice PA was Health. It was verified yet, that women and aged had a higher mean in the Health factor; among the exercise practitioners was found a higher mean in the Appearance factor; and a higher mean in the Social factor was found among those that practice PA with accompaniment. It was concluded that the MPAM-R presented satisfactory psychometric parameters, became it useful in futures researches. Moreover, proposed the accomplishment of new studies that considered others variables to the intent of the better understanding of motivation to practice physical activity