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Os efeitos do ensino de tato para itens de alta e baixa preferência na emergência do mando em crianças com autismo
(Universidade Federal de São Carlos, 2013-07-19) Mendes, Valeria; Goyos, Antônio Celso de Noronha; https://lattes.cnpq.br/3407008711535651; https://lattes.cnpq.br/1579234036925651
Children with atypical development and with verbal behavior deficits, specifically children with autism, can benefit from a systematic teaching of verbal operants and programs that promote its generalization. Verbal behavior is an operant behavior maintained by consequences mediated by a listener that was previously trained by the verbal community to respond to such verbal stimuli. Among the verbal operants, three were of particular interest to this research: echoic, tact and mand. The aim of this research was to examine the effects of tact training for high and low preferred leisure items in the emergence of mand for these same items. Five students with autism (aged from 5 to 14 years old) attending a special education school participated in this research. Participants were exposed one at a time to the experimental conditions and the behavior was observed in the test condition of mand, teaching tact and, then, the effects of the tact teaching was observed in the emergence of mand. The experimental stimuli (leisure items and edibles) were selected from the indication of the parents and teacher, followed by a Forced Choice preference assessment. At the end of the teaching procedure, participants presented tact for high (AP) and low preferred (BP) items. In the mand post-test, participants demonstrated the emergence of this operant with a higher frequency of responses for AP items. The results suggest that the emergence of mands with a higher frequency of responses for AP items may be related to the motivating operation, since the AP items could exert a more reinforcing function than the BP items, which has practical implications for the teaching of verbal behavior.
Desenvolvimento de um potenciostato/galvanostato portátil e eletrodos impressos para determinações in situ em análises em fluxo com transmissão de dados em tempo real
(Universidade Federal de São Carlos, 2013-07-19) Santos, Vagner Bezerra dos; Fatibello Filho, Orlando; https://lattes.cnpq.br/9859737944357808; https://lattes.cnpq.br/5690211284729828
The main purpose of this work was to develop a potentiostat/galvanostat (PG004) to perform the electroactive metallic ions determination in water samples automatically. A dry thermostated electrochemical cell and a flow system with multicommutation were developed based on the use of the solenoid micropumps and valves with screen-printed electrodes (SPE) for the electrochemical measurements with detection employing stopped flow or continuous flow techniques. Two types of the SPE were developed: i) the SPE based on bismuth film (SPE-BiF) electrochemically deposited for on-line and in situ or ex situ modes, and ii) the boron doped diamond coupled to the SPE (SPE-BDD). These devices, and the electrodes were optimized and their performances were evaluated firstly by employing commercially available potentiostat/galvanostat. Thus, individual or simultaneous determination of Zn2+, Cd2+, and Pb2+ ions were carried out using the stopped flow technique and detection employing square-wave anodic stripping voltammetry (SWASV) to the SPE-BiF, and differential pulse (DPASV) for the SPE-BDD. Limits of detection (LDs) of 1.60 μg L-1, 0.30 μg L-1 and 0.09 μg mL-1, respectively were obtained for the simultaneous determination of Zn2+, Cd2+, and Pb2+ ions by using the SPE BiF ex-situ with SWASV. For the BDD-SPE-DPASV, LDs of 2.50 μg L-1, 0.38 μg L-1 and 0.10 μg L-1 were obtained, respectively, for the determination mentioned previously. Determination of analytes individually or simultaneously were also carried out with SPE-BDD employing multiple pulse amperometry (MPA), and LDs of 150 μg L-1, 87.0 μg L-1 and 13.0 μg mL-1 were obtained respectively for simultaneous determination of Zn2+, Cd2+, and Pb2+ ions with a sampling rate of 54 determinations per hour. In parallel with the electroanalyticals determinations, the PG004 was developed according to the following sequence. i) development of the electronic circuits; ii) calibrations of the PG004; iii) assembly of the PG004 with the flow module coupled to it; iv) coupling of the peripheral devices to the CPU of the PG004 for the wireless transmission of the data with Bluetooth®, Wi-Fi® and 3G protocol, and a GPS receiver), and v) connections of the power unit (12 V batteries) and solar board. Then, the PG004 was employed to determine Cd2+ and Pb2+ ions with SPE-BDD and SWASV in laboratory to simulate in situ conditions. Then, the PG004 was placed to the field for in situ determinations of Cd2+ and Pb2+ ions with good results: i) individual and simultaneous determinations of the Cd2+ and Pb2+ ions with recoveries ranged from 93.3 to 109%; ii) voltammograms with no noises and with good resolutions; iii) reception of the geographical coordinates using the GPS receiver and sending experimental data via mobile technology (GPRS); iv) great autonomy of energy due to the solar board; v) automated capture, filtration and thermostatic temperature control for in situ analysis; vi) SPE-BDD and SPE-BiF reusable at the end of the analysis and vii) low waste generation per determination (700 μL).