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Análise de medidas mitigatórias de impactos antrópicos negativos à mastofauna em uma paisagem rural em São Carlos-SP
(Universidade Federal de São Carlos, 2011-06-09) Tezori, Rogerio Franco Flores; Garavello, Júlio César; https://lattes.cnpq.br/2778105126670170; https://lattes.cnpq.br/6262000648248079
The human pressures on natural environments generate fragmentation and loss of habitat, one of the main threats to biodiversity. Using the terrestrial mammals as indicators, it were evaluated the ecological corridor Embrapa- Fazenda Engenho Velho (Old Mill Farm) and a silvopastoral system to determine if they actually mitigate the negative impacts of local farming. Four linear transects were laid in two fragments of semideciduous forest in the ecological corridor that connects them and made 24 observations, including the branch tunnels (one with 0.9 m in diameter and another with 2.5 x2m) under the highway Guilherme Scatena (that divides the ecological corridor) and its coasting. With the data was constructed a dendrogram of similarity (Jaccard coefficient). In the silvopastoral system and conventional grazing, were placed four cages (15x15x40cm) in each and 20 observations were made. The results demonstrate the presence of 27 species in the fragments, seven of which use the corridor and only two uses the tunnel passage. The similarity between the fragments is high (65%), but decays over the corridor (44%) and the tunnel passage (19%), which shows that the ecological corridor is not fulfilling its role of facilitating the exchange of individuals among the fragments for greater genetic variability in local populations. Furthermore, the coasting had 11 species (45% similarity with fragments), but no individual was found run over, suggesting that in this case, the speed bumps installed on the highway are the most effective tools for conservation than the actual tunnel passage. The largest tunnel presented seven species, but lacks the vegetation in the surroundings unlike smaller tunnel, suggesting that for the branch tunnels, it is extremely important to their size. In the silvopastoral system were found four individuals from three genera (Calomys, Akodon and Oligorizomys) and in the common grazing, eight individuals of the genus Calomys, suggesting that silvopastoral systems are better to maintain species richness. We conclude that there are viable alternatives to improve production and maintain biodiversity, native vegetation with the best connection, but the deployments must be accomplished effectively and not only for law enforcement, without ever having a monitoring of its function, as occurs in most rural areas of the country subjected to this type of activity. Also we can t think that the mere fact of clearing vegetation and deploy these systems are solutions to the environmental crisis, but to optimize the use of land already cleared for such deployment.
Registros de movimentos do pescoço: estado da arte, validação e aplicação e avaliação durante o trabalho de técnicos de enfermagem
(Universidade Federal de São Carlos, 2011-06-09) Carnaz, Letícia; Coury, Helenice Jane Cote Gil; https://lattes.cnpq.br/3021199199918426
Neck pain has been highly prevalent among workers. In occupational settings physical risk factors, especially posture, are considered fundamental in neck pain development. However, neck posture and movements have not been properly evaluated at workplace due to the use of not reliable measurement methods. Furthermore, most of the studies that evaluate posture during occupational activities have focused on the wrist and hand assessment. Thus, in order to contribute with information about neck movements recording in occupational settings, three related studies were developed. The aim of the first study was to investigate the applications and limitations of the systems for direct measurement of neck movement in the workplace. The results of this study showed that in most of the articles the three axes of neck movement were not simultaneously recorded. Deficiencies in available equipment explain this flaw, demonstrating that sensors and systems need to be improved so that a true understanding of real occupational exposure can be achieved. Further studies are also needed to assess neck movement in those who perform heavy‐duty work, such as nurses and electricians, since no report about such jobs was identified. Based on these results, an option to record three‐dimensional neck movements in occupational settings is the use of flexible electrogoniometers. But neither electrogoniometers, nor inclinometers (direct measurement most commonly used) were compared with a system considered more accurate and precise. Then, the objective of the second study was to assess concurrent validity between flexible electrogoniometers (EGM), inclinometers (INC) and a three‐dimensional analysis system based on video recording (IMG) in simultaneous and synchronized data collection. EGM presented high differences when compared with INC and IMG. Moreover, the EGM sensors physically restricted the full neck flexion‐extension range of motion. Inclinometers, which cannot record rotation movement, presented good concurrent validity in relation to IMG, except for flexion‐extension movement. Due to non‐optimal conditions during flexion‐extension movement, IMG underestimated these movements. The results of the studies described above designed the third study that aimed to quantify the head, upper back and upper arm postures of practical nurses while performing their occupational activities and to verify if there are differences between the postures of professionals with and without symptoms. The results showed that most of the activities of practical nurses involve considerable postural risk for the head, upper back and upper arms. The postural risk varied among tasks: there was more exposure for the neck region when separating medication and keeping medical records. In general, workers with symptoms in the neck and upper arm region presented greater amplitude of movement and a higher fraction of time spent in awkward postures than asymptomatic workers, but with no significant difference between these two groups.
Análise da influência das condições de mistura por extrusão sobre o comportamento de blendas poliméricas PBT/ABS
(Universidade Federal de São Carlos, 2011-06-09) Prezenszky, André Cortegoso; Hage Júnior, Elias; https://lattes.cnpq.br/1240692926327687; https://lattes.cnpq.br/8881087453572394
At the present work several properties of PBT/ABS blends processed with different extrusion conditions as feed rate, screw speed and profile and die geometry were studied in order to verify how these parameters affect their properties. The specimens were obtained directly from the extruded blends to keep extrusion characteristics on the results. The main reason to add ABS to the PBT was to have tough PBT/ABS blends. It was verified that even without a compatibilizer, impact strength of the blends was higher than the impact strength of neat components. In addition, the ductile brittle temperature transition (DBTT) has decreased almost 60ºC when compared to the neat PBT. It was also verified that differences on processing parameters affect mostly DBTT, exhibiting values in the range of -5ºC to 40ºC. The best results were obtained using higher feed rates, low screw speed rotation, kneading blocks lagged 90º and shorter dies. It was also developed a degradation evaluation method and showed that the thermal mechanical degradation of the blend components can be verified by analyzing the consumption of the double bonds of the polybutadiene rich phase from ABS and the reduction of molecular weight of PBT. Although adequate results were obtained on preliminary degradation analyses of the components mixed in a torque rheometer, the method was insufficiently sensitive to identify significant differences on the degradation of blend components processed in a twin screw extruder.