933 resultados para Estudos de validação


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Formulation Additives on Formation of Films isolated from Ethylcellulose. Physicochemical and Morphological Studies. In this work were developed free films from Surelease (R), additives alpha-GOS (alfa-glucooligosaccharide) and/or Tween (R) 80 in aqueous solution. It was obtained by Teflon plates casting process. The free films were characterized by thermal analysis (DSC and TGA), infrared spectroscopy (FTIR-ATR) and scanning electron microscopy (SEM). DSC and TO analysis showed that the additives do not influenced in the thermal stability of Surelease (R) films. SEM analysis observed homogeneous morphological characteristics and phase detachment absence. FTIR-ATR spectra were used to confirm the physical mixture between the components of films.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work is part of an effort of consolidation of a daily search for powder technology at the Department of Physics of the Universidade Federal do Rio Grande do Norte. This work objective the study and development of new ceramic materials from raw materials abundant at the region. For this, were studied ceramic mixtures of powders from diatomite-titania to aiming at a new ceramic material from powder technology. The experimental work involved a characterization of ceramic powders from a diatomite-titania mixture. The powders obtained were pressed and then parameters like variation of mass, linear shrinkage, activation energy and the mechanism of sintering are studied in function of the time and temperature of sintering, beyond microstructural analysis. The obtained results allow us estimate the optimizing of sintering conditions of this material

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The term fatigability concerns the degree of fatigue associated with performing an activity of any type (physical, mental, emotional and / or social). Recently scales for assessing fatigue in the English language were created, however, gaps exist regarding the validity of these scales in relation to oxygen consumption and levels of perceived fatigue. Objective: To investigate the validity of perceived fatigability scale in older women frail and non-frail by the expired gases kinetics. Methods: This is a study of type validation, where were evaluated 48 elderly. The evaluation was conducted at two different sessions. In the first, data were collected demographic partners, as well as assessment of cognitive function, physical health, and the phenotype of frailty. The second was composed by the test 6-minute walk (6MWT) associated the expired gases kinects and assessment of perceived fatigability. Statistical analysis was performed a descriptive analysis and then we used the Pearson correlation test to evaluate the relationship between the measure of perceived fatigue and variables oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER)before and after 6MWT. We used a linear regression model initially considering the following explanatory variable: age, Body Mass Index (BMI), presence of frailty, comorbidities, level of physical activity, distance covered in the 6MWT , the energy cost of walking and severity of fatigability on performance. Results: The final sample consisted of 44 elderly women, 4 elderly were excluded because they didn t complete all phases of this study. The mean age obtained was 75 years (± 7.2 years). There was no significant correlation between fatigability measures and the values of VO2 ( r = .09 , p = .56 ) , VCO2 ( r = .173 , p = .26 ) , RER ( r = - .121 , p = .43 ). The final linear regression model showed that the energy cost of walking, the usual level of physical activity and the performance severity of fatigability explained 83.5 % (R2 = 0.835, p < 0.01) of the variation in the perceived fatigability. Conclusion: Our findings indicate a relationship between greater severity of fatigability and lower levels of physical activity and increased energy cost in walking, suggesting that the fatigability analyses using a simple numeric scale is valid and viable for assessment of fatigue in older women

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Bacteria trom Shewanella and Geobacter ganera are the most studied iron-reducing microorganisms particularly due to their electron transport systems and contribution to some industrial and environmental problems, including steel corrosion, bioenergy and bioremediation of petroleum-impacted sites. The present study was focused in two ways: the first is an in silico comparative ecogenomic study of Shewanella spp. with sequenced genomes, and the second is an experimental metagenomic work to detect iron-reducing Shewanella through PCR-DGGE of a metabolic gene. The in silico study resulted in positive correIation between copy number of 16S rDNA and genome size in Shewanella spp., with clusters of rrn near lhe origin of replication. This way, the genus is inferred as opportunist. There are no compact genomes and their sequences length varied, ranging from 4306142 nt in S. amazonensis SB2B to 5935403 nt in S. woodyi ATCC 51908, without correIation to temperature range characteristic of each specie. Intragenomic 16S rDNA sequences possess little divergence, but reasonable to resuIt in different phyIogenetic trees, depending on the sequence that is chosen to compare. For moIecuIar detection of iron-reducing Shewanella, it is proposed the mtrB gene as new biomarker. because it codes to a fundamental protein at Fe (III)-reduction. The specific primers were designed and evaluated in silico and resulted in a fragment of 360 pb. In the second study, these primers were tested in a genomic sample from S. oneidensis MR-1, amplifying the expected region. After this successfuI resuIt, the primer set was used as a tool to assess the iron-reducing communities of ShewaneIla genus under an environmental stress, i.e. crude oil contamination in mangrove sediment in Rio Grande do Norte State (Brazil). The primers presented high specificity and the reactions performed resulted in one single band of ampIification in the metagenomic samples. The fingerprinting obtained at DGGE reveaIed temporal variation of Shewanella spp. in analyzed samples. The resuIts presented show the detection of a biotechnological important group of microorganisms, the iron-reducing Shewanella spp. using a metabolic gane as target. It is concluded there are eight or more 16S rDNA sequences in Shewanella genus, with little divergence among them that affects the phylogeny; the pair of primers designed to ampIify mtrB sequences is a viable alternative to detect iron-reducing ShewanelIa in metagenomic approaches; such bacteria are present in the mangrove sediment anaIyzed, with temporal variations in the samples. This is the first experimental study that screened the iron-reducing Shewanella genus in a metagenomic experiment of mangrove sediments subjected to oil contamination through a key metabolic gene

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Some microorganisms from virgin ecosystems are able to use petroleum it as source of carbon and energy. The knowledge of microbial biodiversity can help to reveal new metabolic systems for utilization alkanes with biotechnological importance. The aim of this study is: i) Accomplish an in silico study of the AlkB protein aimed to understand the probable mechanism involved on selectivity of alkanes in Gram positive and Gram negative bactéria. ii) prospect and analyze the response of the microbial alkanotrophics communities in soil and mangrove sediments of BPP RN and soil of Atlantic forest in the Horto Dois Irmãos Reserve area/PE using the molecular biomarker, gene alkB; with the PCR and PCR-DGGE approach

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Esse estudo se propôs a avaliar um método auxiliar de diagnóstico (DIAGNOdent®) na predição de cárie de dentina em dentes decíduos, através de validação histológica e de microdureza. Verificando possíveis diferenças entre os valores obtidos através do método auxiliar, além de determinar um ponto de corte para parada de remoção de tecido cariado. A amostra do estudo foi de 15 crianças que apresentaram 21 cavidades de cárie, tratadas e analisadas desde antes da realização da restauração até quando da exodontia do elemento dentário. Os espécimes foram analisados através do DIAGNOdent® antes da abertura das cavidades, após a remoção do tecido cariado e depois da reabertura das cavidades que se deu após a exodontia dos elementos dentários. Posteriormente, receberam preparo metalográfico para realização de testes de microdureza e microscopia óptica que serviram como forma de validação para as mensurações obtidas pela fluorescência a laser. Houve diferença significativa entre os valores DIAGNOdent® encontrados antes da abertura da cavidade e os demais (p < 0,0001). Havendo correlação significativa (r = 0,432 ; p = 0,019) apenas para as aferições obtidas antes da abertura das cavidades e quando do término da remoção do tecido cariado. Para a microdureza, as médias axiais foram significativamente maiores que as pulpares, existindo correlação entre a microdureza pulpar e os valores do DIAGNOdent® após a reabertura (r = - 0,472 ; p = 0,002). Valores de 15,38% para a sensibilidade, 100% para a especificidade, 100% para o valor preditivo positivo e 71,79% para o valor preditivo negativo, foram obtidos quando se utilizou um ponto de corte de 30 para fluorescência a laser, tendo como padrão-ouro a microdureza pulpar. Partindo da média dos valores de fluorescência a laser obtidos após a remoção do tecido cariado e acrescentando-se um desvio-padrão a esta, o método indicou o valor de 19 como ponto de corte para cessar a remoção de dentina. Concluiu-se que, nas condições analisadas, o método auxiliar de diagnóstico (DIAGNOdent®) é um método acurado na predição de cárie de dentina em dentes decíduos. Além disso, o método comprovou que o padrão usual de remoção de dentina garante a remoção do tecido cariado

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Episodic memory refers to the recollection of what, where and when a specific event occurred. Hippocampus is a key structure in this type of memory. Computational models suggest that the dentate gyrus (DG) and the CA3 hippocampal subregions are involved in pattern separation and the rapid acquisition of episodic memories, while CA1 is involved in memory consolidation. However there are few studies with animal models that access simultaneously the aspects ‗what-where-when . Recently, an object recognition episodic-like memory task in rodents was proposed. This task consists of two sample trials and a test phase. In sample trial one, the rat is exposed to four copies of an object. In sample trial two, one hour later, the rat is exposed to four copies of a different object. In the test phase, 1 h later, two copies of each of the objects previously used are presented. One copy of the object used in sample trial one is located in a different place, and therefore it is expected to be the most explored object.However, the short retention delay of the task narrows its applications. This study verifies if this task can be evoked after 24h and whether the pharmacological inactivation of the DG/CA3 and CA1 subregions could differentially impair the acquisition of the task described. Validation of the task with a longer interval (24h) was accomplished (animals showed spatiotemporal object discrimination and scopolamine (1 mg/kg, ip) injected pos-training impaired performance). Afterwards, the GABA agonist muscimol, (0,250 μg/μl; volume = 0,5 μl) or saline were injected in the hippocampal subregions fifteen minutes before training. Pre-training inactivation of the DG/CA3 subregions impaired the spatial discrimination of the objects (‗where ), while the temporal discrimination (‗when ) was preserved. Rats treated with muscimol in the CA1 subregion explored all the objects equally well, irrespective of place or presentation time. Our results corroborate the computational models that postulate a role for DG/CA3 in spatial pattern separation, and a role for CA1 in the consolidation process of different mnemonic episodes

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Bipolar disorder has been growing in several countries. It is a disease with high mortality and has been responsible by the social isolation of the patients. Bipolar patients have alterations in circadian timing system, showing a phase shift in various physiological variables. There are several arguments demonstrating alterations in circadian rhythms may be part of the bipolar disorder pathophysiology. Given the necessity for further elucidation, the goal of this study was to validate the forced desynchronization protocol as an animal model for bipolar disorder. To do this, Wistar rats were submitted to a forced desynchronization protocol which consists in a symmetrical light dark cycle with 22h. Under this protocol, rats dissociate the locomotor activity rhythm into two components: one synchronized to the light / dark cycle with 22h, and another component with period longer than 24 hours following the animal endogenous period. These rhythms with different periods sometimes there is coincidence, which we named CAP (Coincidence Active Phase) and the opposite phase, non-coincidence, called NCAP (Non-Concidence Active Phase). The hypothesis is that in CAP animals present a mania-like behavior and animals in NCAP depressive-like behavior. We found some evidence described in detail throughout this thesis. In sum, the animals under forced desynchronization protocol were more stressed, showed an increase in stereotypic behaviors such as grooming and reduction in other behaviors such as risk assessment and vertical exploration when compared to the control group. The CAP animals showed increased locomotor activity, especially during the dark phase when compared to controls (rats under T24) and less depressive behavior in the forced swim test. The animals in NCAP showed a higher anxiety in elevated plus maze, but they don t have ahnedonia. The animals under dissociation have more labeled 5HT1A cells at the amygdala area, which appoint that they have more amygdala inhibition. Taking these data together, we could partially validated the forced desynchronization protocol as an animal model for mood oscillations

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Currently, several psychological and non-psychological tests can be found in publishes without standardization on procedures set in different psychological areas, like intelligence, emotional states, attitudes, social skills, vocation, preferences and others. The computerized psychological testing is a extension of traditional testing psychological practices. However, it has own psychometrics qualities, either by its matching in a computerized environment or by the extension that can be developed in it. The current research, developed from a necessity to study process of validity and reliability on a computerized test, drew a methodological structure to provide parallel applications in numerous kinds of operational groups, evaluating the influences of the time and approach in the computerization process. This validity refers to normative values groups, reproducibility in computerized applications process and data processing. Not every psychological test can be computerized. Therefore, our need to find a good test, with quality and plausible properties to transform in computerized application, leaded us to use The Millon Personality Inventory, created by Theodore Millon. This Inventory assesses personality according to 12 bipolarities distributed in 24 factors, distributed in categories motivational styles, cognitive targets and interpersonal relations. This instrument doesn t diagnose pathological features, but test normal and non adaptive aspects in human personality, comparing with Theodore Millon theory of personality. In oder to support this research in a Brazilian context in psychological testing, we discuss the theme, evaluating the advantages and disadvantages of such practices. Also we discuss the current forms in computerization of psychological testing and the main specific criteria in this psychometric specialized area of knowledge. The test was on-line, hosted in the site http://www.planetapsi.com, during the years of 2007 and 2008, which was available a questionnaire to describe social characteristics before test. A report was generated from the data entry of each user. An application of this test was conducted in a linear way through a national coverage in all Brazil regions, getting 1508 applications. Were organized nine groups, reaching 180 applications in test and retest subject, where three periods of time and three forms of retests for studies of on-line tests were separated. Parallel to this, we organized multi-application session offline group, 20 subjects who received tests by email. The subjects of this study were generally distributed by the five Brazilian regions, and were noticed about the test via the Internet. The performance application in traditional and on-line tested groups subsidies us to conclude that on-line application provides significantly consistency in all criteria for validity studied and justifies its use. The on-line test results were related not only among themselves but were similar to those data of tests done on pencil and paper (0,82). The retests results demonstrated correlation, between 0,92 and, 1 while multisessions had a good correlation in these comparisons. Moreover, were assessed the adequacy of operational criteria used, such as security, the performance of users, the environmental characteristics, the organization of the database, operational costs and limitations in this on-line inventory. In all these five items, there were excellent performances, concluding, also, that it s possible a self-applied psychometric test. The results of this work are a guide to question and establish of methodologies studies for computerization psychological testing software in the country

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Parenting styles concern overall interaction characteristics between parents and children. To assess them, it is important to build and adapt valid and reliable instruments. The main objectives of this dissertation were to translate, adapt and evaluate the psychometric properties of the Young Parenting Inventory (YPI) for the Brazilian context, as seek associations between the YPI and Familiogram Test (FG). In current study, YPI was adapted to Portuguese by backtranslation method. Content analyses were made by five judges. 920 high school and college students (543 females), whose ages were between 14 and 69 years (M = 21.3, SD = 6.1), filled out the research instruments. Data were collected in Natal, Petrolina and Brasilia cities and Porto Alegre metropolitan region. The results confirmed the existence of five factors. Final version of the YPI was composed by 49 items. Exploratory factorial analysis (principal components) were conducted using oblimin rotation. Five factors extracted explained 45.12% of the maternal scale variance and 47.59% of paternal scale. Each factor explained, at least, 3% of the variance and showed Eigenvalue over than 1.5. All items have factorial loadings values above 0.3. The confirmatory factorial analysis has showed fit statistics reasonably adequate: for maternal scale,  ² [1114] = 4636.38, p < 0.001,  ² / df = 4.16, with GFI = 0.83, AGFI = 0.81 and RMSEA = 0.06; for paternal scale,  ² [1114] = 5133.69 p < 0.001,  ² / df = 4.61, with GFI = 0.81, AGFI = 0.79 and RMSEA = 0,06. Thus, final instrument was composed by the following factors: (I) Disconnection and Rejection ( = 0.89 and 0.90), (II) Affectivity and Emotional Stability ( = 0.85 and 0.88); (III) Overvigilance and Other Directedness ( = 0.83 and 0.85), (IV) Overprotection and Impaired Autonomy ( = 0.78 and 0.79) and (V) Impaired Limits ( = 0.66 and 0.71). Finally, relations between the YPI and FG were assessed. Pearson's correlations between the YPI and FG showed moderated associations, particularly between the factors Affectivity (YPI) and Affection (FG) (r = 0.69 and 0.7 for maternal and paternal scale, respectively); and the factors Disconnection and Rejection (YPI) and Conflict (FG) (r = 0.59 and 0.58). The regression models indicated that over than 40% of variance of factors of FG can be predicted by factors of YPI. Beta coefficients for Affection-Affectivity relation were 0.67 (maternal scale) and 0.53 (paternal scale); for Disconnection-Conflict relation were 0.31 (maternal scale) and 0.44 (paternal scale). We conclude the YPI has adequate psychometric parameters and can be used in future research in this area. However, adjustments in the structure of the YPI were made. Moreover, it is suggested further studies to consider other samples and variables, increasing the knowing of parenting styles and the Young‟s theory in the Brazilian context

Relevância:

20.00% 20.00%

Publicador:

Resumo:

While providing physical and psychological benefits, excessive exercise could be or cause a compulsive behavior, making the individual dependent on it. In a parallel discussion, computerized psychological instruments, for a hand, reflects the development of information technology and your applicability to other areas, but also shows little advance for Psychological Assessment. In this perspective, this study aims to adapt the Exercise Dependence Scale (EDS-R) in two formats (paper-and-pencil and computerized) and evaluate evidence of factorial and convergent validity, and reliability of each version and compare them with each other. It is also proposed to observe the relationship of some bio-demographic (Sex, age, frequency, duration and intensity of practice exercise) and the exercise dependence (DEF). For this purpose, 709 regular physical activity practitioners, selected by procedures non-probabilistic sampling, responded a adapted version of EDS-R, Muscle Appearance Satisfaction Scale (MASS), Body Modification Scale (BMS) and a demographic questionnaire, analyzed through Exploratory Factor Analysis, Cronbach's Alpha and not parametric tests. Both the traditional version and the computer showed a seven factors structure, explaining 57 and 62% of the variance, respectively, and Cronbach's alphas of 0.83 and 0.89. Factors were: (1) intentionality, (2) continuity, (3) tolerance, (4) reduction of other activities, (5) lack of control, (6) abstinence and (7) time spent on exercise. Relationships were observed between the Exercise Dependence and the variables: age, diets, consumption of food supplements and medicines for weight change, desire to do plastic surgery and body satisfaction. We observed also a positive correlation between the DEF and the frequency, duration and intensity of exercise, and the factor "Dependence on exercising" from MASS, indicating convergent validity of the EDS-R. Finally, comparisons between the two formats were equivalent, with few changes: computerized version achieved higher DEF scores. Based on these results, it can be concluded that the EDS-R has factorial and convergent validity, reliability, to measure exerceise dependence on traditional e computerized formats. DEF is related to actions used to body modification and behaviors toward exercise. Finally, it was found equivalence between the formats, especially in psychometric parameters, thus suggesting feasibility of a computerized assessment. However, it was observed that the computerized data has sample recruiting strategies more limited