Desempenho cognitivo-linguístico e leitura em escolares com transtorno do déficit de atençào e hiperatividade

OBJECTIVE: the aim of this study was to compare the cognitive-linguistic skills performance and reading of students with Attention Deficit and Hyperactivity Disorder and students without behavioral and/or learning disorders. METHOD: the study included 20 students from 5th to 8th grade of elementary school. The students were divided into: Group I (GI): composed by 10 students with an interdisciplinary diagnosis of Attention Deficit and Hyperactivity Disorder, and Group II (GII): composed by 10 students without complaints of behavioral and/or learning disorders. The tests of metalinguistic skills and reading (PROHMELE) were used as procedure, composed of syllabic and phonemic identification, syllabic and phonemic manipulation, repetition of nonwords and reading tests. RESULTS: the results showed statistically significant differences between GI and GII, demonstrating that students from GI presented superior performances when compared to the students from GII. CONCLUSION: according to the findings of this study we can conclude that the difficulties presented by students with Attention Deficit and Hyperactivity Disorder can be attributed to inattention, hyperactivity and disorganization, characteristic of this diagnosis, and not to a disorder of language of phonological basis.

Study of thermal decomposition of ignition temperature of bagasse, coal and their blends

In Brazil, due to its availability, sugar cane bagasse has a high potential for power generation. The knowledge of ignition behavior, as well as the knowledge of the chemical kinetics, in of fuels combustion process is important features in boilers projects and in the stability of the combustion process control. The aim of this study is to investigate the thermal behavior of sugar cane bagasse, coal and their blends. The methodology proposed by Tognotti et al. (1985) was applied to determine the ignition temperature for all samples. Ignition temperatures were 256oC for neat bagasse and 427oC for neat coal, and 275oC for both blends (50-50% and 25-75%). The ModelFree Kinetics was applied to determine the apparent activation energy (Eα) of the thermal decomposition of sugar cane bagasse. For the two major events of mass loss of bagasse which correspond to the thermal decomposition of organic matter (mainly hemicellulose, cellulose and lignin), average values of Eα were obtained for both combustion and pyrolysis processes. In synthetic air atmosphere, the Eα were 170.8±26.3 kJ⋅mol-1 and 277.8±58.6 kJ⋅mol-1, while in nitrogen atmosphere, the Eα were 185.0 ± 11.4 kJ⋅mol-1 and 82.1±44.4 kJ⋅mol-1. The results obtained can be explained by synergistic effects when both bagasse and coal were blended, changing the fuel reactivity.