Effects of strontium and calcium simultaneous substitution on electrical and structural properties of Pb1-x-y Ca (x) Sr (y) TiO3 thin films

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

Encoding mechanisms based on fast oscillations in the retina of the cat and their dependencies on anesthesia

Processing in the visual system starts in the retina. Its complex network of cells with different properties enables for parallel encoding and transmission of visual information to the lateral geniculate nucleus (LGN) and to the cortex. In the retina, it has been shown that responses are often accompanied by fast synchronous oscillations (30 - 90 Hz) in a stimulus-dependent manner. Studies in the frog, rabbit, cat and monkey, have shown strong oscillatory responses to large stimuli which probably encode global stimulus properties, such as size and continuity (Neuenschwander and Singer, 1996; Ishikane et al., 2005). Moreover, simultaneous recordings from different levels in the visual system have demonstrated that the oscillatory patterning of retinal ganglion cell responses are transmitted to the cortex via the LGN (Castelo-Branco et al., 1998). Overall these results suggest that feedforward synchronous oscillations contribute to visual encoding. In the present study on the LGN of the anesthetized cat, we further investigate the role of retinal oscillations in visual processing by applying complex stimuli, such as natural visual scenes, light spots of varying size and contrast, and flickering checkerboards. This is a necessary step for understanding encoding mechanisms in more naturalistic conditions, as currently most data on retinal oscillations have been limited to simple, flashed and stationary stimuli. Correlation analysis of spiking responses confirmed previous results showing that oscillatory responses in the retina (observed here from the LGN responses) largely depend on the size and stationarity of the stimulus. For natural scenes (gray-level and binary movies) oscillations appeared only for brief moments probably when receptive fields were dominated by large continuous, flat-contrast surfaces. Moreover, oscillatory responses to a circle stimulus could be broken with an annular mask indicating that synchronization arises from relatively local interactions among populations of activated cells in the retina. A surprising finding in this study was that retinal oscillations are highly dependent on halothane anesthesia levels. In the absence of halothane, oscillatory activity vanished independent of the characteristics of the stimuli. The same results were obtained for isoflurane, which has similar pharmacological properties. These new and unexpected findings question whether feedfoward oscillations in the early visual system are simply due to an imbalance between excitation and inhibition in the retinal networks generated by the halogenated anesthetics. Further studies in awake behaving animals are necessary to extend these conclusions

Direct and simultaneous spectrophotometric determination of Ni (II) and Co (II) using diethanoldithiocarbamate as complexing agent

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

Finding the Higgs boson through supersymmetry

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Atividade do professor na educação a distância: interações com o gênero profissional docente

This research aimed to analyze the dynamics established between the activity of the teacher in Distance Education (DE) and professional gender of teaching, in terms of impact of DE in teacher s usual professional activity. Previous studies showed that one of the central discussions concerning DE refers to the role that the teacher is called to perform. The present research, based on theoretical and methodological assumptions issued from Clinic of Activity, analyzed the impact referred above. This central aim was operationally executed along three main stages: 1) survey study for description of socio-professional profile of teachers working in DE in two universities from Natal (RN-Brazil), 2) clinical analysis of professional activity of teachers working in DE, taking into account four simultaneous levels of psychological constitution and development of human activity: personal, interpersonal, transpersonal and impersonal; 3) analytical focus on transpersonal context in order to understand the influence of pedagogical practice in DE on professional gender of teaching. Documental research, audio recorded voice data and a multiple choice Likert scale questionnaire concerning socio-professional information were used as procedural tools. The qualitative-clinical procedural tool of instruction to the double , firstly proposed by Clinic of Activity research group, was used in order to obtain oral productions concerning professional activity. Data issued from stage 1 (n=70, 28 men and 41 women) was submitted to descriptive and inferential statistical analyzes. 65.7% of the sample worked in a public institution, 30% in a private institution, and 4.3% in public and private institutions. 31.4% of the sample of participants was formed by teachers having a master degree, 28.6% were doctors and 26.3% had degrees of specialists. 54.3% of participants acted as remote tutor, and 44.3% were regents teachers. After descriptive multidimensional cluster analysis, two groups emerged (remote tutors and regents teachers), the most important variables in terms of contributions to this distinction being: professional function, level of graduate formation, level of income, activities and forms of entry in DE. Clinical analysis of data produced by two participant-teachers of each group, issued from instruction to the double technique, was performed. This analysis indicated the existence of different models of distance education. A general concern referring to the need of both taking into account information technology and pedagogical attitudes was detected. On the other hand, participant-teachers considered that participation in DE activities could bring relevant contributions to general professional gender of teaching. . Finally, teachers warned against certain formats of organization of teachers professional activity, as found in the domain of DE, since these activities could promote the intensification and individualization of teachers` work activity, and even the worsening of relations, rather than exchanges and shares through collective bargaining. This process could compromise the renew of the professional gender, by losing its historical roots and diminishing activity possibilities of teachers in their labor context

Associação entre doença arterial coronariana e as pregas lobular diagonal e anterotragal em homens

FUNDAMENTOS: Diversas alterações dermatológicas foram associadas à doença arterial coronariana, representando achados de fácil constatação que podem contribuir na estratificação não invasiva do risco cardíaco. OBJETIVOS: Avaliar comparativamente a prevalência de certos achados dermatológicos em pacientes com ou sem doença arterial coronariana. MÉTODOS: Estudo caso/controle envolvendo pacientes do sexo masculino submetidos à cineangiocoronariografia. Foram considerados aqueles casos com obstrução de mais de 50% em pelo menos uma coronária. Avaliou-se a presença da prega lobular diagonal, prega anterotragal, alopecia e presença de pêlos no tórax nos dois grupos. Os resultados foram ajustados para os fatores de risco: tabagismo, hipertensão, diabetes, idade, dislipidemia e índice de massa corporal. RESULTADOS: Analisaram-se 110 pacientes (80 casos e 30 controles). A prevalência da prega lobular diagonal nos casos (60,0%) foi maior do que no grupo controle (30,0%) (p<0,05). Alopecia androgenética e distribuição de pêlos no tórax não demonstraram associação positiva com coronariopatia neste estudo. O Odds Ratio (IC 95%), da prega lobular diagonal foi de 3,1 (1,2-8,3) e para prega anterotragal foi de 5,5 (1,9-16,3). A verificação simultânea da prega lobular diagonal e prega anterotragal representou valor preditivo positivo de 90%. CONCLUSÕES: Detectou-se associação positiva entre a presença da prega lobular diagonal bilateral e prega anterotragal bilateral com doença arterial coronariana, sendo que a presença simultânea das duas pregas apresenta alta preditividade para doença arterial coronariana.

Recession Defects Associated With Scraped Roots Treated With Subepithelial Connective Tissue Graft

The objective of the current study was to assess histo-morphometrically the healing process of recession defects associated with scraped roots treated with subepithelial connective tissue graft (SCTG). Six dogs were used. Bone dehiscence defects (6 x 8 mm) and root planing were carried out on maxillary canine teeth. Following a split-mouth model, according to the treatment, left canines (control) were covered with coronally positioned flap (CPF). Right canines were submitted to treatments with SCTG. After a 3-month postoperative period, the animals were killed, and the blocks processed for the histomorphometric assessment. Data assessment demonstrated that the CPF group showed parameters of a new connective tissue attachment, length of new cement (NC), length of new bone (mean +/- SD: 0.95 +/- 0.53, 2.44 +/- 1.97, and 1.96 +/- 2.29 mm, respectively), which were higher than those of SCTG group (mean +/- SD: 0.71 +/- 0.36, 2.21 +/- 1.28, and 1.52 +/- 1.31 mm, respectively), although not significantly (P > 0.05). The length of both epithelial tissue and connective tissue apposition in the SCTG group (mean +/- SD: 1.70 +/- 0.53 and 2.62 +/- 1.52 mm, respectively) were higher than those of the CPF group (mean +/- SD: 1.18 +/- 0.49 and 2.03 +/- 1.03 mm, respectively), although showing no significant differences (P > 0.05). Within the limits of the current study, it was possible to conclude that there were no significant differences between the groups according to the histologic parameters assessed.

Fracture strength of flared bovine roots restored with different intraradicular posts

Objective: The aim of this study was to evaluate the fracture strength and failure mode of flared bovine roots restored with different intraradicular posts. Material and Methods: Fifty bovine incisors with similar dimensions were selected and their roots were flared until 1.0 mm of dentin wall remained. Next, the roots were allocated into five groups (n=10): GI-cast metal post-and-core; GII-fiber posts plus accessory fiber posts; GIII-direct anatomic post; GIV-indirect anatomic post and GV-control (specimens without intraradicular post). A polyether impression material was used to simulate the periodontal ligament. After periodontal ligament simulation, the specimens were subjected to a compressive load at a crosshead speed of 0.5 mm/min in a servo-hydraulic testing machine (MTS 810) applied at 135 to the long axis of the tooth until failure. The data (N) were subjected to ANOVA and Tukey's post-hoc test (alpha=0.05). Results: GI and GIV presented higher fracture strength (p<0.05) than GII. GIII presented intermediate values without statistically significant differences (p>0.05) from GI, GII and GIV. Control specimens (GV) produced the lowest fracture strength mean values (p<0.05). Despite obtaining the highest mean value, GI presented 100% of unfavorable failures. GII presented 20% of unfavorable failures. GIII, GIV and GV presented only favorable failures. Conclusions: Although further in vitro and in vivo studies are necessary, the results of this study showed that the use of direct and indirect anatomic posts in flared roots could be an alternative to cast metal post-and-core.

Phenylalanine ammonia-lyase activity in soybean roots extract measured by reverse-phase high performance liquid chromatography

The high performance liquid chromatography (HPLC) technique was applied to measure phenylalanine ammonia-lyase (PAL, EC 4.3.1.5) activity in soybean (Glycine max L. Merril cv. BR16) roots. t-Cinnamate, the catalytic product of the PAL reaction was quantified at 275 nm by isocratic elution with methanol:water through an ODS(M) column. Comparative experiments were carried out with 1.0 mM ferulic acid, an inducer of PAL activity. The results suggest that liquid chromatography is a rapid and sensitive method to analyze PAL activity in non-purified extract.

Perforated ray cells in the wood of roots and branches of cerrado species from Brazil

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

The Tomato (Solanum Lycopersicum cv. Micro-Tom) Natural Genetic Variation Rg1 and the DELLA Mutant Procera Control the Competence Necessary to Form Adventitious Roots and Shoots

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

Anti-inflammatory effects and acute toxicity of hydroethanolic extract of Jacaranda decurrens roots in adult male rats

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

MORPHOLOGICAL EVIDENCE FOR PROTANDRIC SIMULTANEOUS HERMAPHRODITISM IN THE CARIDEAN EXHIPPOLYSMATA OPLOPHOROIDES

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Population dynamics, sex ratio and size at sex change in a protandric simultaneous hermaphrodite, the spiny shrimp Exhippolysmata oplophoroides

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