Equilíbrio líquido-líquido de sistemas aquosos com tensoativos polietoxilados: dados experimentais e modelagem

The nonionic surfactants when in aqueous solution, have the property of separating into two phases, one called diluted phase, with low concentration of surfactant, and the other one rich in surfactants called coacervate. The application of this kind of surfactant in extraction processes from aqueous solutions has been increasing over time, which implies the need for knowledge of the thermodynamic properties of these surfactants. In this study were determined the cloud point of polyethoxylated surfactants from nonilphenolpolietoxylated family (9,5 , 10 , 11, 12 and 13), the family from octilphenolpolietoxylated (10 e 11) and polyethoxylated lauryl alcohol (6 , 7, 8 and 9) varying the degree of ethoxylation. The method used to determine the cloud point was the observation of the turbidity of the solution heating to a ramp of 0.1 ° C / minute and for the pressure studies was used a cell high-pressure maximum ( 300 bar). Through the experimental data of the studied surfactants were used to the Flory - Huggins models, UNIQUAC and NRTL to describe the curves of cloud point, and it was studied the influence of NaCl concentration and pressure of the systems in the cloud point. This last parameter is important for the processes of oil recovery in which surfactant in solution are used in high pressures. While the effect of NaCl allows obtaining cloud points for temperatures closer to the room temperature, it is possible to use in processes without temperature control. The numerical method used to adjust the parameters was the Levenberg - Marquardt. For the model Flory- Huggins parameter settings were determined as enthalpy of the mixing, mixing entropy and the number of aggregations. For the UNIQUAC and NRTL models were adjusted interaction parameters aij using a quadratic dependence with temperature. The parameters obtained had good adjust to the experimental data RSMD < 0.3 %. The results showed that both, ethoxylation degree and pressure increase the cloudy points, whereas the NaCl decrease

A new method to quantify macroalgae and a practical sampler for experimentation in lotic habitats

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Trabalhos prático-experimentais no ensino da biologia: Uma análise dos livros didáticos de Biologia aprovados no PNLD/2012

El trabajo práctico experimental en la educación en Ciencias y en el contexto de la enseñanza de la Biología es un objetivo clave. Teniendo en cuenta la influencia de los libros de texto en la actividad profesional de docentes, interesado en este estudio para caracterizar la orientación de este tipo de materiales, para el trabajo práctico experimental y el uso de la medición en esta actividad. Para ello analizaron las ocho colecciones de libros de Biología aprobado en PNLD en 2012. La investigación es de naturaleza descriptiva e interpretativa y de recogida de datos ha sido elegida por el método de análisis de contenido (BARDIN, 2002). El análisis de los trabajos práctico experimentales buscó caracterizar su naturaleza epistemológica, concepción de la ciencia implícita, conceptual, tipología, contenido conceptual de Biología utilizado, cuántos implican medidas, y cómo se utiliza en este contexto según el procedimiento general para medir propuesto por Núñez y Silva (2008). Los trabajo práctico experimental ha sugerido una epistemología de la enseñanza conceptual, carácter racionalista en su mayoría y dominada por las actividades del tipo de ejercicio práctico, a necesidad de medir está presente en una minoría de estos y se se utiliza el procedimiento general de medición de forma parcial e implícito en la mayoría de los trabajos prático experimentales. Por lo tanto, proponemos en este actividades de estudio a desarrollar una guía de análisis de los trabajo práctico experimentales propuesto en los libros de texto de Biología

Antibióticos antifúngicos produzidos por actinomicetos do Brasil e sua determinação preliminar nos meios experimentais

Várias amostras de solo do Brasil foram semeadas em placas de ágar e diversas cepas de actinomicetos produtoras de antibióticos antifúngicos foram isoladas. Foram desenvolvidos meios para eliciação da biossíntese dos antibióticos e métodos para determinação rápida do seu rendimento. Ao todo, foram isoladas 41 cepas de actinomicetos aeróbios produtoras de metabólitos antifúngicos. Destes, 11 (26,8%) eram macrolídeos tetraênicos, 13 (31,7%) macrolídeos pentaênicos, 1 (2,4%), macrolídeo oxopentaênico, 1 (2,4%) macrolídeo hexaênico e 6 (14,6%) macrolídeos heptaênicos. Os antibióticos antifúngicos produzidos pelas restantes 9 cepas ativas (21,9%) não eram poliênicos. Os poliênicos mais utilizados atualmente na clínica são do tipo tetraênico (nistatina) e heptaênico (anfotericina B). Um meio à base de leite de soja favoreceu extraordinariamente a eliciação da biossíntese de polienos por algumas cepas, enquanto que para outras não houve favorecimento e para outras foi prejudicial. Os rendimentos obtidos atingiram cerca de 6000 U de antibióticos poliênicos por mL.

Espectro das ondas de spin lineares e não-lineares em multicamadas magnéticas anisotrópicas

Conselho Nacional de Desenvolvimento Científico e Tecnológico

Efeitos do treino em esteira com suporte parcial de peso e do método de facilitação neuromuscular proprioceptiva na marcha hemiparética: estudo comparativo

Objective: To compare the effects of the treadmill training with partial body-weight support (TPBWS) and Proprioceptive Neuromuscular Facilitation (PNF) method on gait of subjects with chronic stroke. Design: Quasi-experimental study. Setting: Laboratorial research. Participants: Twenty-three subjects (13 men and 10 women), with a mean age of 56,7 ± 8,0 years and a mean time since the onset of the stroke of 27,7 ± 20,3 months, and able to walk with personal assistance or assistive devices. Interventions: Two experimental groups underwent gait training based on PNF method (PNF group, n=11) or using the TPBWS - Gait Trainer System 2, Biodex, USA (TPBWS group, n=12), for three weekly sessions, during four weeks. Measures: Evaluation of motor function - using the Stroke Rehabilitation Assessment of Movement (STREAM) and the motor subscale of the Functional Independence Measure (motor FIM) -, and kinematic gait analyze with the Qualisys System (Qualisys Medical AB, Gothenburg, Sweden) were carried out before and after the interventions. Results: Increases in the STREAM scores (F=49.189, P<0.001) and in motor FIM scores (F=7.093, P=0.016), as well as improvement in symmetry ratio (F=7.729, P=0.012) were observed for both groups. Speed, stride length and double-support time showed no change after training. Differences between groups were observed only for the maximum ankle dorsiflexion over the swing phase (F=6.046, P=0.024), which showed an increase for the PNF group. Other angular parameters remain unchanged. Conclusion: Improvement in motor function and in gait symmetry was observed for both groups, suggesting similarity of interventions. The cost-effectiveness of each treatment should be considered for your choice

Stress entre calouros e veteranos de jornalismo

A vida na universidade corresponde a um período no qual os indivíduos são expostos a influências psicossociais que podem desencadear situações estressoras, prejudicando a saúde e a qualidade de vida dos estudantes. Nessa perspectiva, o objetivo deste estudo foi analisar as diferenças de sintomas, níveis e presença de stress entre calouros (n=57) e veteranos (n=48), de ambos os sexos, do curso de jornalismo de uma universidade pública no interior do Estado de São Paulo. Foi aplicado aos participantes o Inventário de Sintomas de Stress de Lipp. Dos resultados obtidos, destacam-se: predominância de stress entre as mulheres; maior número de alunos estressados e na fase de quase-exaustão no último ano; predomínio de sintomas físicos entre calouros e psicológicos entre veteranos. Pesquisas são necessárias para elaboração de políticas institucionais que promovam condições favoráveis a um melhor desenvolvimento das potencialidades acadêmicas dos alunos.

Estudo da adsorção de hidrogênio e sulfeto na superfície de paládio: aspectos experimentais (eletroquímica) e teóricos (ab initio e Teoria do Funcional da Densidade)

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

Avaliação longitudinal do impacto da saúde bucal na estratégia saúde da família em Natal

As a result of the financial incentive provided by the GM / MS 1.444, since 2000, Brazil has experienced a substantial increase in the number of oral health services at the Family Health Strategy. There is, however, evidence that these teams have produced qualitatively different experiences which do not translate necessarily into improved quality of life and health. Thus, evaluative research of great importance. This study aims to assess the impact of the Family Health Strategy in oral health in a longitudinal perspective natalense the years 2006 and 2009. This is an intervention study whose design is a community trial in parallel, nearly randomized. The sample consisted of census tracts covered by oral health teams in the Family Health and the Traditional Model (Basic Health Units and non-FHS Program of Community Health Agents and areas not covered.) The sample was determined by drawing ten census tracts to form the experimental group and ten other sectors for the control group by pairing intentional based on socio-economic and geographic. To check the net effect of the intervention was performed multivariate analysis by Poisson regression. As a result of cross-sectional analysis of year 2009, it was found that the effects of the ESF in Natal were satisfactory only for the variables of injuries and for other purposes without and with negative impact on stock coverage reclaimers. However, the longitudinal analysis revealed that the ESB / ESF improved their performance in dealing with grievances, access and coverage of the type of actions and this fact is independent of age, sex and social and economic conditions. In other employees' words are related to the presence of the Family Health Strategy in the region. However it does not say that both models under study (the Family Health Strategy Model and Traditional) are different in terms of performance and it is pertinent to reflect on the need for further development of evaluation studies that use other approaches able to clarify the dynamics of the process whose results can come to the knowledge of the actors responsible for leading the ESF and encourage them to incorporate the assessment in their routine

Caracterização comportamental endócrina das fases ontogenéticas de sagüi comum (Callithrix jacchus)

The use of animal models in biomedical research is ever increasing. Models that use primates might also have advantages in terms of low maintenance costs and availability of biological knowledge, thereby favoring their use in different experimental protocols. Many current stress studies use animal models at different developmental stages since biological response differs during ontogeny. The aims of this study were to perform a detailed characterization of the developmental stages of common marmosets (Callithrix jacchus), a very important animal model used in biomedical research. Ten subjects, 6 females and 4 males, were followed from birth to initial adult age (16 months). Behavioral and fecal collection for measurement of adrenal (cortisol) and sex (progesterone, estradiol and androgens) hormones took place twice a week during the first month of life and once a week for the remainder of the study. Behavior was observed for 30 minutes in the morning (0700-09:00h) and afternoon (12:00-14:00h). Behavioral profile showed changes during ontogeny, characterizing the 4 developmental stages and the respective phases proposed by Leão et al (2009).. Differentiation of developmental stages was considered using the onset, end, change and stabilization of the behavioral profile parental care (weaning and carrying), ingestion (solid food), affiliation (social grooming) and autogrooming, agonism (scent marking and piloerection) and play behavior and endocrine profile. Infant weaning and carrying terminated within the infantile stage and the peak of solid food ingestion was recorded in the infantile III phase. Receiving grooming was recorded earlier than grooming performed by the infant and autogrooming. The first episode of scent marking was recorded in the 4th week and it was the least variable behavior, in terms of its onset, which, in almost all animals, was between the 5th and 7th week of life. Solitary play and play with the twin started around the 7th week and play with other members of the group started 8 weeks later. Sex hormone secretion started to differ from basal levels between the 21st and 23rd week of life, in males and females, suggesting that puberty occurs simultaneously in both sexes. Basal cortisol, even at an early age, was higher in females than in males. However, cortisol was not correlated with the juvenile stage, as expected, since this stage corresponds to the transition between infancy and adult age and most behaviors are intensified by this time. The behavioral and endocrine profile of subadult animals did not differ from that of the adults. These results provide more detailed parameters for the developmental process of C. jacchus and open new perspectives for the use of experimental approaches focused on the intermediate ontogenetic phases of this species

O papel das relações sociais e da atenção social durante tarefas cooperativas em Callithrix jacchus

Several studies on nonhuman primates show that the relationships between individuals strongly influence the expression of cooperative behavior, both in natural environment and in captivity settings. Recent studies suggest that cooperative breeders present outstanding performance in tasks involving social cognition, such as cooperative tasks with experimental apparatuses. In experimental research on this subject it is crucial to differentiate between real cooperation (or communicative cooperation, mediated by social attention) and by-product cooperation that results from simultaneous actions of individuals. The present study assessed, in Callithrix jacchus, a cooperative breeder species, if social relationships and social attention between subjects are important factors during performance in cooperative tasks. During the experimental procedure the animals participated in three different cooperative tasks: cooperation task, prosocial task and control task. Diverging from the literature, matrix correlation tests revealed no significant relationship between grooming or proximity and the execution of the tasks, suggesting that other factors such as age or hierarchy may have an effect on the performance in cooperative tasks in this species. There was also no relationship between the execution of the cooperative tasks and social glances, suggesting that there was no social attention during the tasks. Moreover, there were lower rates of social glances in the cooperative tasks as opposed to the control tasks. However, the small number of pulls in prosocial tasks suggests that the animals distinguished between tasks that benefited only a partner and tasks that generated benefits to themselves, choosing the latter. We conclude that, for the tasks presented in this study, we could neither detect the role of social relationships on the cooperative tasks nor assert that there were true cooperation and prosocial behavior

Resiliência e socialização organizacional de novos servidores: um estudo transcultural

The main aim of the study was to analyze the relationship between resilience and organizational socialization among newcomers from the Federal University of Rio Grande do Norte (UFRN), and the Norwegian University of Science and Technology (NTNU), comparing the results obtained in a cross-cultural perspective. The sample (N=205) was composed of mentored (N=70) and non-mentored (N=72) professors and technical-administrative employees at UFRN, and their non-mentored counterparts at NTNU (N=63). The data collection instruments used were the Organizational Socialization Inventory (OSI), the Resilience Scale for Adults (RSA) and a sociodemographic form. Data analysis was preceded by a number of tests to verify possible distinct response styles among the respondents, as they came from different cultures. Descriptive analysis and t-tests were performed to identify and compare organizational socialization and resilience outcomes. Hierarchical regression analyses were carried out, the first ones involving all participants (N=205), to observe the predictive power of resilience factors in relation to organizational socialization factors, beyond the effects of nationality, occupation and mentoring experience. The other hierarchical regression analyses were conducted separately for the professors (N=109) and technical-administrative employees (N=96); and for the mentored (N=70) and non-mentored newcomers from UFRN (N=72), and nonmentored newcomers from NTNU (N=63), to compare the predictive power of resilience in relation to organizational socialization between newcomers from the two occupations, and also among the three groups of participants. The results of this study showed that socialization and resilience profiles differed according to demographic and cultural characteristics, and to the socialization strategies adopted in the institutions studied. Furthermore, it was observed that resilience added a significant incremental prediction to all socialization factors, beyond nationality, occupation, and mentoring experience. The predictive contribution from each of the resilience factors was also noteworthy, mainly those of Planned Future and Social Resources. With respect to nationality, occupation and mentoring experience, it was noted that they explained a significant part of the variance in almost all organizational socialization factors, in addition to playing a meaningful role in predicting the scores of such factors, with some evidence of moderation or mediation by the resilience factors. Considering these and the comparative results of the predictive power of resilience in relation to the organizational socialization, between the two occupations and among the three groups of participants, as a whole, the main findings of this study were as follows: resilience tends to contribute to organizational socialization outcomes; the resilience of some subjects may be a differential factor for success in those situations in which individuals face working conditions that are less favorable to promoting their adaptation; and, a formal mentoring program may contribute to improving newcomer resilience, producing better and more homogeneous organizational socialization outcomes. The practical implications, limitations and main contributions of the study are discussed, with a number of suggestions for future research

Crianças no pátio escolar :a utilização dos espaços e o comportamento infantil no recreio

The interest for understanding the relationship of the child with its environment has increased in the whole world during the last few years. Several researchers, using Environmental Psychology as basis, have analyzed the implications of this relation for the child development and the organization of playful spaces. Being a place where children spend a great part of their time and develop many intellectual and social abilities, the school becomes one of the main focus of this research. This study investigated different sectors of the outdoor area of NEI -UFRN, during the recreation time, in which the use of space and the interaction between children were analyzed, through the observation of the child behavior (place-centered and individual-centered mapping). The results had disclosed that the school s outdoor area and its equipments presents a great range of choices possible to the children, however its occupation is not uniform: there are areas very used and others almost without use. Generally, this heterogeneity happens again in relation to the distribution of the interaction states in the sectors, the friendly associative behavior being the most present. The observation of children behaviors favored a better understanding of the use of the spaces, and contributed for discussion about the environment what these users really need for a healthy development, including differences in related to gender, age and daytime. In spite of the studied outdoor areas being vast, pleasant and varied, it needs a better distribution of its equipments and a plan that allows greater children participation in the place organization

Análise dos Processos de Flotação e Oxidação Avançada para o Tratamento de Efluente Modelo da Indústria do Petróleo

The generation of wastes in most industrial process is inevitable. In the petroleum industry, one of the greatest problems for the environment is the huge amount of produced water generated in the oil fields. This wastewater is a complex mixture and present great amounts. These effluents can be hazardous to the environmental without adequate treatment. This research is focused in the analysis of the efficiencies of the flotation and photo-oxidation processes to remove and decompose the organic compounds present in the produced water. A series of surfactants derivated from the laurilic alcohol was utilized in the flotation to promote the separation. The experiments have been performed with a synthetic wastewater, carefully prepared with xylene. The experimental data obtained using flotation presented a first order kinetic, identified by the quality of the linear data fitting. The best conditions were found at 0.029 g.L-1 for the surfactant EO 7, 0.05 g.L-1 for EO 8, 0.07 g.L-1 for EO 9, 0.045 g.L-1 for EO 10 and 0.08 g.L-1 for EO 23 with the following estimated kinetic constants: 0.1765, 0.1325, 0.1210, 0.1531 and 0.1699 min-1, respectively. For the series studied, the most suitablesurfactant was the EO 7 due to the lower reagent consumption, higher separation rate constant and higher removal efficiency of xylene in the aqueous phase (98%). Similarly to the flotation, the photo-Fenton process shows to be efficient for degradation of xylene and promoting the mineralization of the organic charge around 90% and 100% in 90 min

As relações afetivas na prática tutorial e sua relações com a aprendizagem no curso a distância de licenciatura plena em Química

In distance learning degree in Chemistry in full of the Secretária de Educação a distância da Universidade Federal do Rio Grande do Norte (SEDIS / UFRN). The teacher-tutor to establish the experimental subjects closer relationships with students, mediating the pedagogical actions that develop in the distance learning course, with a view to achieving the principles of autonomy and learning, contributing to the creation of learning environments collaborative, guided by affection.The article presents the results of an empirical research on affectivity in practice this tutorial experimental classes in higher distance education in the full degree course in Chemistry Polo Currais Novos/ RN, held between 2009 and 2010. The study is based on qualitative methodology, whose data were collected through questionnaires and semi-structured interviews with 48 (forty eight) students involved in distance learning courses and selected in order to compose a group of subjects who showed variability, as guidelines that guide the sampling procedures in qualitative research. The results, based on category theory and empirical analysis of data from the interviews were supplemented by information obtained from participant observation which also served to guide the data collection of the corpus of this work. With the results we understand that there is clarity about what characterizes a loving relationship between those involved in the process of teaching and learning in experimental classes in high school chemistry Distance Education. Furthermore, it was also clear that the communication process in dialogic teaching and learning in higher distance education in chemistry at the trial need to mark out in balanced affective attitudes, the experimental error that value and respect the many possible construction of knowledge by movements social interaction of individual and collective