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O conceito de símbolo em Sidman e Skinner - uma análise epistemológica
(Universidade Federal de São Carlos, 2012-06-04) Rocca, Julia Zanetti; Pessotti, Isaias; https://lattes.cnpq.br/2793069740146109; https://lattes.cnpq.br/7678523240628345
The theory of language created by Skinner in the 1950s rejected traditional terms such as reference , meaning and symbol , due to considering such terms useless and inadequate to a science of verbal behavior. Still, since the 1960s new theories of language in behavioral analysis have come to make use of these terms both to describe phenomena and to define concepts. In order to investigate this theoretical dissonance, the present work analyses the concepts of reference , meaning and symbol in the theories of Skinner and Sidman. In regards to Skinner, the investigation has implied in (I) the analysis of the theories of language that have exerted influence on his work in order to understand the rejection of both reference and symbolism; (II) the description of the theoretical path of construction of a science of verbal behavior through an operationalist conception of language. In the case of Sidman, the theory of language arises as a result of experimental discoveries, which by its turn demanded from the conceptual investigation: (I) the description of the origin of the technical terms used in the field through Sidman s and his predecessor s researches; (II) the analysis of potential theoretical influences upon conceptual formalization of the stimulus equivalence paradigm. As the result, it has been verified that the theories of both Sidman and Skinner share the influence of the logical branch of the Philosophy of Language, and especially of the Logical Positivists. However, while Sidman s work is close to these philosopher s initial theories, Skinner s work is characterized as critical in relation to them. Moreover, the epistemological analysis of the stimulus equivalence paradigm has allowed the conclusion that this model adopts strictly operationalist presuppositions, and beyond that, of an Skinnerian Operationalism that is to say, different both from Bridgman s original version and from other psychological versions, such as Stevens . And since Operationalism would be the most important basis for the analysis of language proposed by Skinner, the conceptual differences between the theories of Sidman and Skinner appear to coexist with a confluence in their epistemological foundations.
Participação dos neurônios noradrenérgicos da região A5 no controle cardiorrespiratório durante a hipercapnia e hipóxia em ratos
(Universidade Federal de São Carlos, 2012-06-04) Taxini, Camila Linhares; Moreira, Thiago dos Santos; https://lattes.cnpq.br/0243906744273591; Batalhão, Luciane Helena Gargaglioni; https://lattes.cnpq.br/5850453468994497; https://lattes.cnpq.br/6604038939386546
The noradrenergic A5 group is an important group of neurons located in the ventrolateral pons and receives projections from several medullar areas related to cardiorespiratory regulation. The A5 region contributes to the maturation of the respiratory system before birth and in adult rats these neurons are connected with the neural network responsible for respiratory rhythmogenesis. The A5 neurons have an important involvement in autonomic control, these neurons send and receive projections from various regions involved in cardiovascular control, and send projections directly to the intermidial column lateral. Thus, we tested the hypothesis that noradrenergic neurons of A5 region participate in cardiorespiratory responses produced by hypercapnia or hypoxia in anesthetized and ananesthetized rats. In ananesthetized animals without and sino-aortic denervation, the lesion of the noradrenergic neurons in the A5 region with anti-dopamine β-hydroxylase-saporin (anti-DβH-SAP, 4.2 ng) promoted a decrease of tidal volume response to acute hypercapnia (7% CO2, 30 minutes) and acute hypoxia (7% O2, 30 minutes), but did not alter the cardiovascular response. In anesthetized animals during the acute hypercapnia (5% to 10% CO2, 5 minutes), the bilateral microinjection of muscimol (GABA-A agonist; 2 mM) and the chemical injury with anti-DβH-SAP on the A5 region reduced the increase of mean arterial pressure (MAP), splanchnic sympathetic activity (sSNA), frequency and amplitude of phrenic nerve produced by hypercapnia. During acute hypoxia (8-10% O2, 30 seconds) the bilateral microinjection of muscimol in the A5 region attenuated the increase in MAP and sSNA promoted by hypoxia without affecting the activity of the phrenic nerve, but the chemical injury of A5 region not altered responses promoted by hypoxia. The results of this study show that the participation of the A5 region in cardiorespiratory response depends on the animal's condition, anesthetized or not, as well as CO2 and O2 levels. In animals ananesthetized, the noradrenergic neurons of A5 region exert an excitatory modulation in control of tidal volume in response to hypercapnia and hypoxia. While in anesthetized animals, this region stimulates the cardiorespiratory response to hypercapnia, increasing the amplitude and frequency of the phrenic nerve, and sympathetic activity.
Avaliação da resposta de bovinos Nelore e cruzados, Senepol x Nelore e Angus X Nelore, infestados com carrapato Rhipicephalus (Boophilus) microplus
(Universidade Federal de São Carlos, 2012-06-04) Ibelli, Adriana Mércia Guaratini; Regitano, Luciana Correia de Almeida; https://lattes.cnpq.br/4729789236742545
Infestations caused by ectoparasites are among the main problems that affect stock raising in tropical countries, and in Brazil, the Rhipicephalus (Boophilus) tick is responsible for substantial losses in the animal production. The aim of this study was to evaluate the response of three genetic groups of cattle artificially infested with Rhipicephalus (Boophilus) microplus. For this, skin samples from Nellore (NX) and crossbreeds, Senepol x Nellore (SN) and Angus x Nellore (TA) heifers were collected before and 24 hours after the last artificial infestation with Rhipicephalus (Boophilus) microplus larvae for gene expression analysis and histology. We collected hair and performed behavioral analysis in order to relate them to the cattle parasite load. There were significant differences (P <0.01) for the tick count within three studied groups. TA animals (0.92 ± 0.07) had higher mean and the NX group (0.28 ± 0.07), the lowest mean. In the differential leukocyte count, TA animals had higher numbers of monocytes that NX (P <0.05), not differing from SN. No significant differences were evaluated for other leukocytes. However, the NX genetic group had higher mean for mast cells than SN and TA (P <0.01). NX had more CD4 cells that TA that did not differ from SN. Negative correlation was observed between the number of ticks and CD4 T cells. In the hair and haircoat analysis, TA showed the higher values of haircoat mean (CP) and mass density (MD) of hair than SN and NX (p <0.05), which did not differ from each other. For the number of hairs per sample and number of hair/cm2, NX had larger mean (p <0.05) than SN and TA, which did not differ. Results of Pearson correlations indicated that CP and DM have a positive correlation (p <0.05) with tick count. Regarding grooming behavior it has been observed that the total of self-grooming, as well as, allogrooming events influenced the tick count evaluated, and that there is a negative correlation with the tick number, helping to reduce this parasite, especially in Nellore. On 1, 4, 6 and 7 days after infestation and at the times 7:00, 9:00 and 12:00 h animals performed more grooming events when compared to other periods. According to the large scale gene expression results, there was no difference within genetic groups. The comparison between the groups before and after 24 hours infestation showed that 1,502 genes were differentially expressed. Of these, 851 were activated and 651 had reduced expression after challenge. The microarray experiment was validated by quantitative real time PCR. 12 Among the genes and pathways activated in response to tick, the chemokine genes, MAPK signaling pathways and Jak-Stat, cytokine receptors, complement and focal adhesion molecules as well as calcium channel genes stood out. Such genes and pathways can be identified as candidates to play the role of host protection at this time of bovine parasitic cycle. In this way, it was observed that mechanisms as grooming and increase of mast cells should confer resistance to tick. Furthermore, we found metabolic pathways that were not previously described in the literature may be novel targets for the development of strategies prevent tick infestation, as vaccines and drugs.