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Search Results: 1 - 10 of 902730 matches for " A. L. R. M.;Piedade "
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Production of 15N-enriched nitric acid (H15NO3)
Sant Ana Filho, C. R.;Bendassolli, J. A.;Rossete, A. L. R. M.;Piedade, S. M. S.;Prestes, C. V.;
Brazilian Journal of Chemical Engineering , 2008, DOI: 10.1590/S0104-66322008000400011
Abstract: techniques that employ 15n have proved to be an important tool in many areas of the agronomic and biomedical sciences. nevertheless, their use is limited by methodological difficulties and by the price of compounds in the international market. nitric compounds (15no3-) have attracted the interest of researchers. however, these compounds are not currently produced in brazil. thus, in the present work h15no3 was obtained from the oxidation of anhydrous 15nh3. the method we used differs from the industrial process in that the absorption tower is replaced with a polytetrafluoroethylene-lined, stainless-steel hydration reactor. the process output was evaluated based on the following parameters: reaction temperature; ratio of reagents; pressure and flow of 15nh3(g) through the catalyst (pt/rh). the results showed that, at the best conditions (500 oc; 50 % excess o2; 0.4 mpa; and 3.39 g.min-1 of 15nh3), a conversion percentage (n-15nh3 to n-15no3-) of 62.2 %, an overall nitrogen balance (n-15nh3 + n-15no3-) of 86.8 %, and purity higher than 99 % could be obtained.
Crescimento e qualidade de mudas de pinh?o-manso produzidas em ambiente protegido
Paulino, Janaina;Folegatti, Marcos V.;Flumignan, Danilton L.;Zolin, Cornélio A.;Barboza Júnior, Cícero R. A.;Piedade, S?nia M. de S.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2011, DOI: 10.1590/S1415-43662011000100006
Abstract: there has been an increasing interest in the commercial production of physic nut (jatropha curcas l.) due to the recent brazilian program of biofuel production. information on this crop is still scarce and more research is necessary to set the grounds of crop adaptability in different local conditions. an experiment was set up on this issue under greenhouse environment. growth and quality of physic nut seedlings was monitored up to transplanting time. the influence of types and volumes of seedling containers was analysed along with different substrates and fertilization strategies. the water use was also detailed in the trial. results showed the best achievements of growth rate and seedling quality, at appropriate transplanting time, were reached from the combination of the commercial substrate, largest containers and fertilizers of slow nutrient liberation.
Effects of caffeine on the electrophysiological, cognitive and motor responses of the central nervous system
Deslandes A.C.,Veiga H.,Cagy M.,Piedade R.
Brazilian Journal of Medical and Biological Research , 2005,
Abstract: Caffeine is the most consumed psychoactive substance in the world. The effects of caffeine have been studied using cognitive and motor measures, quantitative electroencephalography (qEEG) and event-related potentials. However, these methods are not usually employed in combination, a fact that impairs the interpretation of the results. The objective of the present study was to analyze changes in electrophysiological, cognitive and motor variables with the ingestion of caffeine, and to relate central to peripheral responses. For this purpose we recorded event-related potentials and eyes-closed, resting EEG, applied the Stroop test, and measured reaction time. Fifteen volunteers took caffeine (400 mg) or placebo in a randomized, crossover, double-blind design. A significant reduction of alpha absolute power over the entire scalp and of P300 latency at the Fz electrode were observed after caffeine ingestion. These results are consistent with a stimulatory effect of caffeine, although there was no change in the attention (Stroop) test or in reaction time. The qEEG seems to be the most sensitive index of the changes produced by caffeine in the central nervous system since it proved to be capable of detecting changes that were not evident in the tests of cognitive or motor performance.
Effects of caffeine on the electrophysiological, cognitive and motor responses of the central nervous system
Deslandes, A.C.;Veiga, H.;Cagy, M.;Piedade, R.;Pompeu, F.;Ribeiro, P.;
Brazilian Journal of Medical and Biological Research , 2005, DOI: 10.1590/S0100-879X2005000700011
Abstract: caffeine is the most consumed psychoactive substance in the world. the effects of caffeine have been studied using cognitive and motor measures, quantitative electroencephalography (qeeg) and event-related potentials. however, these methods are not usually employed in combination, a fact that impairs the interpretation of the results. the objective of the present study was to analyze changes in electrophysiological, cognitive and motor variables with the ingestion of caffeine, and to relate central to peripheral responses. for this purpose we recorded event-related potentials and eyes-closed, resting eeg, applied the stroop test, and measured reaction time. fifteen volunteers took caffeine (400 mg) or placebo in a randomized, crossover, double-blind design. a significant reduction of alpha absolute power over the entire scalp and of p300 latency at the fz electrode were observed after caffeine ingestion. these results are consistent with a stimulatory effect of caffeine, although there was no change in the attention (stroop) test or in reaction time. the qeeg seems to be the most sensitive index of the changes produced by caffeine in the central nervous system since it proved to be capable of detecting changes that were not evident in the tests of cognitive or motor performance.
Memória de procedimentos e SPECT cerebral: avalia??o de fluxo sanguíneo cerebelar e em córtex pré-frontal durante uma tarefa visuo-motora
Silva, Márcia Thereza;Piedade, Roberto;Ribeiro, Pedro;Fonseca, Léa Mirian B. da;Pellini, Marcos Pinto;Cagy, Maurício;
Arquivos de Neuro-Psiquiatria , 2007, DOI: 10.1590/S0004-282X2007000300022
Abstract: the objective of the present study was to evaluate the cerebral blood flow in the cerebellar (4 sub-regions) and pre-frontal cortex, when subjects were in rest and during a motor task performance. the sample consisted of 8 healthy subjects, male or female, between 23 and 36 of age. the visuo-motor task _ implicit memory _ requires the subjects to navigate and swerve a graphic submarine from missiles that run on the screen. semi-quantitative analysis with brain spect (99mtc-ecd) was used to evaluate regional perfusion. the results revealed an increased activity in all areas of interest during motor task. in conclusion, four sub-regions of cerebellar cortex and both pre-frontal hemispheres showed a simultaneous activation during task. moreover, our findings suggest as seen in previous experiments that the central nervous system operates in a parallel fashion, in order to integrate sensory and motor information.
Gamma band oscillations in parietooccipital areas during performance of a sensorimotor integration task: a qEEG coherence study
Teixeira, S;Velasques, B;Machado, S;Paes, F;Cunha, M;Budde, H;Anghinah, R;Basile, L F H;Cagy, M;Piedade, R;Ribeiro, P;
Arquivos de Neuro-Psiquiatria , 2011, DOI: 10.1590/S0004-282X2011000300007
Abstract: this study aimed to elucidate cortical mechanisms involved in anticipatory actions when 23 healthy right-handed subjects had to catch a free falling object through quantitative electroencephalogram (qeeg). for this reason, we used coherence that represents a measurement of linear covariation between two signals in the frequency domain. in addition, we investigated gamma-band (30-100 hz) activity that is related to cognitive and somatosensory processes. we hypothesized that gamma coherence will be increase in both parietal and occipital areas during moment after ball drop, due to their involvement in manipulation of objects, visuospatial processing, visual perception, stimuli identification and attention processes. we confirmed our hypothesis, an increase in gamma coherence on p3-p4 (t= -2.15; p=0.033) and pz-oz (t= -2.16; p=0.034) electrode pairs was verified for a paired t-test. we conclude that to execute tasks involving anticipatory movements (feedforward mechanisms), like our own task, probably, there is no need of a strong participation of visual areas in the process of information organization to manipulate objects and to process visuospatial information regarding the contact hand-object.
Active replication of hepatitis B virus (HBV) in HIV type 1 and in HIV type 2 infected patients
Barros, M.F.;Piedade, J.;Nunes, G.;Canas-Ferreira, W.;Silva, A.P.;Champalimaud, J.L.;Machado-Caetano, J.A.;
Revista do Instituto de Medicina Tropical de S?o Paulo , 1996, DOI: 10.1590/S0036-46651996000400003
Abstract: to evaluate the effect of concurrent infection by hiv on hbv infection or immunity, we have studied a group of 66 hiv1+ symptomatic caucasian patients and another of 38 african hiv2+ asymptomatic individuals, concerning their hbv status: serological markers of infection and presence of hbv-dna in serum, the last taken as sign of hepatitis b virus active replication, were monitored. hiv+ groups were compared with seronegative controls, adequately matched for age, sex and ethnological background. hbv dna was found in 7.6% of hiv1+ caucasian patients and 3.2% of seronegative controls; in african hiv2+ individuals 2.6% were also hbv dna+, a percentage close to that found in hiv2 seronegative controls (2.9%). no correlation was found between hiv infection and hbv active replication. immunodepression that follows hiv infection over time may be compatible with a degree of t cell function capable of avoiding reinfection with or reactivation of hbv, even in symptomatic stages of acquired immunodeficiency syndrome. our findings are relevant to the choice of preventive strategies in populations at risk for hiv and hbv infection.
Desempenho vegetativo e produtivo de cultivares e linhagens de soja de ciclo precoce no município de Piracicaba-SP
C?MARA, G.M.S.;PIEDADE, S.M.S.;MONTEIRO, J.H.;GUERZONI, R.A.;
Scientia Agricola , 1998, DOI: 10.1590/S0103-90161998000300008
Abstract: as part of the official network trials for soybean (glycine max l. merrill) cultivar screening in the state of s?o paulo-brazil, a field experiment was installed in piracicaba, to evaluate the growth and yield performance of short maturity genotypes. the experiment was arranged in a randomized block design with 20 treatments (cultivars and breeding lines) and 4 replications on a kandiudalfic eutrodox soil. the plots were 2.50 m wide and 5.0 m long, with 4 planting lines spaced 0.50 m. the cultivar ias-5 (the most used in the state of s?o paulo) and iac-17 (with high yields in the trials of the last years) were introduced as standards for comparision with the newly developed cultivars and lines. the following characteristics were evaluated: initial plant population, flowering date, maturation date, plant height at flowering and maturation, first pod insertion height, degree of lodging and grain yield. lower plant population reduced plant height at maturation, first pod insertion height and grain yield. the lines br 92-4428, br 92-6528, iac 93-680, iac 90-938, ids 413-f4, iac 93-598 and iac 90-1000 were the most productive, with yields above the standards. the lines ft 90-2687 and br 92-5261 presented the lowest yields.
Desempenho vegetativo e produtivo de cultivares e linhagens de soja de ciclo precoce no município de Piracicaba-SP
C?MARA G.M.S.,PIEDADE S.M.S.,MONTEIRO J.H.,GUERZONI R.A.
Scientia Agricola , 1998,
Abstract: Como parte da rede oficial do Estado de S o Paulo relativa à competi o de linhagens de soja, desenvolveu-se no município de Piracicaba-SP, durante o ano agrícola 1996/97, experimento de campo visando avaliar o desempenho vegetativo e produtivo de linhagens e cultivares de soja (Glycine max L. Merrill) pertencentes ao ciclo de matura o precoce. Delineado em blocos ao acaso com 20 tratamentos (linhagens e cultivares) e 4 repeti es, o experimento foi instalado em Terra Roxa Estruturada eutrófica. As parcelas foram constituídas por 4 linhas espa adas entre si de 0,50 m com 5,0 m de comprimento. Como padr es de compara o das novas linhagens, foram utilizados os cultivares IAS-5 (atualmente o mais cultivado no Estado de S o Paulo) e IAC-17 (com elevada produtividade nos últimos ensaios no Estado de S o Paulo). Foram avaliadas as seguintes características: estande inicial; época de florescimento; época de matura o; altura de planta no florescimento e na matura o; altura de inser o da primeira vagem; grau de acamamento e rendimento em gr os. Concluiu-se que: a) baixo estande de plantas promoveu menor altura final, menor altura de inser o de vagem e menor rendimento em gr os; b) as linhagens BR 92-4428, BR 92-6528, IAC 93-680, IAC 90-938, IDS 413-F4, IAC 93-598 e IAC 90-1000, foram as mais produtivas, superando ambos os padr es; c) as linhagens FT 90-2687 e BR 92-5261, apresentaram os piores rendimentos.
Effect of aerobic training on EEG alpha asymmetry and depressive symptoms in the elderly: a 1-year follow-up study
Deslandes, A.C.;Moraes, H.;Alves, H.;Pompeu, F.A.M.S.;Silveira, H.;Mouta, R.;Arcoverde, C.;Ribeiro, P.;Cagy, M.;Piedade, R.A.M.;Laks, J.;Coutinho, E.S.F.;
Brazilian Journal of Medical and Biological Research , 2010, DOI: 10.1590/S0100-879X2010007500041
Abstract: the effect of physical exercise on the treatment of depressive elderly adults has not been investigated thus far in terms of changes in cortical hemispheric activity. the objective of the present study was to identify changes in depressive symptoms, quality of life, and cortical asymmetry produced by aerobic activity. elderly subjects with a diagnosis of major depressive disorder (dsm-iv) were included. twenty patients (70% females, 71 ± 3 years) were divided into an exercise group (pharmacological treatment plus aerobic training) and a control group (undergoing pharmacological treatment) in a quasi-experimental design. pharmacological treatment was maintained stable throughout the study (antidepressants and anxiolytics). subjects were evaluated by depression scales (beck depression inventory, hamilton depression rating scale, montgomery-asberg depression rating scale) and the short form health survey-36, and electroencephalographic measurements (frontal and parietal alpha asymmetry) before and after 1 year of treatment. after 1 year, the control group showed a decrease in cortical activity on the right hemisphere (increase of alpha power), which was not observed in the exercise group. the exercise group showed a significant decrease of depressive symptoms, which was not observed in the control group. this result was also accompanied by improved treatment response and remission rate after 1 year of aerobic exercise associated with treatment. this study provides support for the effect of aerobic training on alpha activity and on depressive symptoms in elderly patients. exercise facilitates the treatment of depressive elderly adults, leading to clinical and physical improvement and protecting against a decrease in cortical activity.
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