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Fotossensibilizadores no controle de larvas do Aedes aegypti (Diptera : Culicidae)
(Universidade Federal de São Carlos, 2015-08-31) Souza, Larissa Marila de; Kurachi, Cristina; https://lattes.cnpq.br/0194007981724312; Bagnato, Vanderlei Salvador; https://lattes.cnpq.br/4947860249518663; https://lattes.cnpq.br/4920199290813124
The Aedes aegypti mosquito is the main responsible for the transmission of dengue. Among numerous alternatives to combat vector, we can cite the use of photosensitizers (PSs) as inactivating of Aedes aegypti larvae. These compounds are able to interact with the light in a specific wavelength, so the cause highly reactive cytotoxic oxygen, resulting in the oxidation of biological targets. The present study had as main objective to analyze the phototoxic effects of PSs: Photogem® and turmeric, in three molecular variations (curcumin, curcuminoids pigment mixture (curcumin, desmethoxycurcumin and bisdemethoxycurcumin) and curcumin in sucrose), against Aedes aegypti larvae under different conditions of delivery of the PSs and lighting. The experiments of this study were divided into two stages: i) Photogem® and the three compositions of turmeric were applied in trials of photodynamic inactivation (PDI) in solution. The groups that received the Photogem®, were also fed with two different types of food, in order to verify the influence of these foods on larval mortality. ii) in a second step the three compositions of turmeric were incorporated in pet food, where it obtained a lyophilized powder, which was subsequently offered to the larvae for scanning. After the receipt of the PSs in solution as in the form of freeze-dried powder, the larvae were irradiated with two sources of light: artificial and natural. In addition to the trials of mortality, other studies were performed, such as checking the time of degradation of PSs when exposed to light, the anatomical location of accumulation of FSs in the larvae, and characterization studies of the product obtained in the form of lyophilized powder. On PDI with the Photogem® comparing the foods, exposed to artificial lighting, one of the foods introduced a higher mortality, indicating the importance of this on effectiveness of PDI. Already on PDI with variations of turmeric, mortality rates varied according to the molecular forms of this compound, showing high mortality for curcumin and curcumin in sucrose. In conditions involving sunlight, high mortality rates were obtained for all FSs delivered solution, featuring in various conditions 100% mortality in 8 hours from exposure to light. For IFD using the freeze-dried powder of three variations of turmeric and sunlight, mortalities in the order of 80% were achieved in lighting 16 hours. The analysis of the fluorescence image obtained by confocal microscope showed that both the three variations of turmeric, such as Photogem®, after an incubation period of 12 hours, accumulated throughout the alimentary canal of the larvae. The Photogem®, as well as turmeric showed potent photodynamic activity being more effective in conditions with higher light intensities. Regarding the delivery conditions of the PS, we observe that the highest values of mortality were obtained through the application of PSs in solution, when compared with the mortality studies using the freeze-dried powder. These results indicate that PDI can be a promising technique in the control of vectors as the Aedes aegypti.
Sementes orgânicas : regulamentação, políticas públicas, produção comercial e uso de sementes locais em estabelecimentos certificados
(Universidade Federal de São Carlos, 2015-08-31) Parra Filho, Antonio Carlos Mendes; Jovchelevich, Pedro; https://lattes.cnpq.br/9792841909904436; Norder, Luiz Antonio Cabello; https://lattes.cnpq.br/0080353709980071; https://lattes.cnpq.br/2390258036926717
The seed is the first link in the food production chain. In this context, the use of appropriate seeds and seedlings in organic production can be understood as, more than a legal or philosophical question, a technical strategy to better results in organic production. The objectives of this study were: contextualize, analyze and interpret the seed laws, public policies related to local seeds; analyze the standards related to the use of seed in organic production in Brazil; the commercial production of organic seeds in Brazil by the private sector, public sector and third sector; and the use of local seeds by certified establishments. The Brazilian regulations preserved the primary rights of traditional farmers and communities regarding the use and local seed multiplication. Thus, the National Plan for Organic Production and Agroecology (Planapo) gathered some public policies that were based on those rights. Brazilian regulations allowed the use of conventional seeds and seedlings in organic production while there is no supply of organic seeds in the formal market. This is an indicative of the conventionalization process. Commercial production of organic seeds was more significant among third sector organizations linked to family farmers and philosophical currents, which were identified as the pioneers of the organic agriculture movement. Thus, we also see the greatest indexes of local seeds use among organizations of the third sector and family farms.
Estudo de algoritmos para a determinação da temperatura de fusão
(Universidade Federal de São Carlos, 2015-08-31) Michelin, José Vitor; Rino, José Pedro; https://lattes.cnpq.br/6801067322823031; https://lattes.cnpq.br/4394314973749403
In this work, we studied the main methods used in molecular dynamics simulations to obtain the melting temperature of crystalline materials. The methods evaluated were the solid-liquid coexistence, mechanical melt of bulk, melt with surfaces, Lindemann criterion and the method of hysteresis. The potential that we used were the Lennard- Jones for argon, the Embedded Atom Method for copper, the potential of Born-Mayer-Huggins for sodium chloride and the potential of Stillinger-Weber, Modified Embedded Atom Method and EDIP for silicon. We perform all simulations in NPT ensemble and obtained results with good agreement with literature. Some method showed better performance for specific types materials, as in the case of surface melt for copper. The method hysteresis showed fantastic results, proving to be a good alternative to traditional methods to obtain the melting temperature, as the phase coexistence. The results showed that the choice of appropriate interaction potential is a highly determining factor for obtaining good results for studying the properties of interest.
Agentes mineralizadores e seus efeitos nas características morfológicas e físico-químicas de aluminas calcinadas
(Universidade Federal de São Carlos, 2015-08-31) Oliveira, Daniela Riello Gomes de; Pandolfelli, Victor Carlos; https://lattes.cnpq.br/7369376873984839; https://lattes.cnpq.br/8034337197861293
Calcination is an important step in the alumina production process, affecting the final properties of the resulting powder and the attained product. Over the previous decades, attempts have been conducted to understand this process aiming to decrease the calcination temperature and time, additionally to the improvement of the alumina properties. In this sense, the use of additives is promising as these mineralizers, like fluorides, act decreasing the transformation temperature from the transition alumina to the alpha phase. In this context, this study addressed the understanding of the influence of three different additives (solid fluoride, soluble fluoride and seeds) on the properties of the calcined alumina, considering the actual condition of the industry and focusing in technical aspects such as morphology, surface area, primary crystal size, alpha content and the soda decrease. There are several theories about the working reaction of these additives, however, no experimental procedure was carried out to prove those mechanisms. In this work, the AlF3 and the soluble fluoride's mechanism reaction were investigated by using DTA-TG-MS techniques. The results showed that the presence of fluoride in transition aluminas leads to the generation of gaseous compounds which are responsible for speeding up the mass transportation, thus, decreasing the temperature and energy required for obtaining the alpha phase. These mineralizers also influenced the alumina properties, such as an increase in the primary crystal size and a decrease in the surface area. The optimum properties can be attained by the right balance between temperature and mineralizer content. Other additives sources, such as NH4Cl, can be used for decreasing the soda content. This work highlights that their efficiency is directly related to a suitable gas confinement inside of the calciner.
Desenvolvimento de nanocompósitos poliamida 11 / dióxido de titânio para aplicação na indústria petrolífera
(Universidade Federal de São Carlos, 2015-08-31) Balarim, Caio Vinicius Morisco; Hage Junior, Elias; https://lattes.cnpq.br/1240692926327687; Ambrósio, José Donato; https://lattes.cnpq.br/9470914895315270; https://lattes.cnpq.br/4428286340255472
The depth at which explores offshore oil grew abruptly, forcing the advancement of technology in relation to the knowledge acquired so far. For the risers operating conditions, subject to internal relatively low pressures, but exposed to high traction levels, the failure of the tensile armor connection due to disruption of the outer plastic layer has been appointed as the main failure mode to be investigated. The breakdown of protective layers allows the passage of corrosive solutions (gas and sea water) into the duct, accelerating the degradation process by the combination of factors associated with fatigue and corrosion. As a result, the verification of useful life of these risers is becoming increasingly important, justifying the development of reliable methods of inspection and high technologies that increase the estimated life of the components. In this study, the effects of the surface chemical modification of titanium dioxide (TiO2) nanoparticles and their addition into polyamide 11 (PA11) on the mechanical, dynamic-mechanical, and tribological properties of PA11/TiO2 nanocomposites were investigated, aiming the use in the outer plastic layer of offshore risers. The nanoparticles were incorporated by means of two different processes: by extrusion and by internal mixer Haake. The results led to the conclusion that the incorporation of titanium dioxide nanoparticles (TiO2) in a polyamide 11 (PA11) matrix has promising application potential in increasing the life cycle of the outer layer, especially with regard to increased the wear resistance. However, this conclusion is valid only if an appropriate dispersive and distributive mixing is obtained, since the differences between modified and non-modified composites are more strongly influenced by the dispersion of load than by the chemical compatibility between the PA 11 matrix and the modifier.
Análise das variáveis ambientais causadas pelas mudanças dos usos e cobertura da terra do município de São Carlos, São Paulo, Brasil
(Universidade Federal de São Carlos, 2015-08-31) Trevisan, Diego Peruchi; Moschini, Luiz Eduardo; https://lattes.cnpq.br/2728357583462262; https://lattes.cnpq.br/2413871825446601
Anthropogenic impacts tend to simplify natural ecosystems, reducing the inherent resistance to change and breaking their resilience thresholds in more than one place at a time. Such interference in the landscape converts extensive and continuous areas of forest cover in forest fragments, affecting the availability and quality of natural resources. It is essential to analyze the municipality in its local and regional geographical context as well as the study of typically urban and agricultural structures, aiming at establishing forms of growth and consolidation consistent with sustainable development goals. Given these considerations, this study aimed to obtain landscape information in the Brazilian city of São Carlos (SP) using landscape structural indices. Data were entered and analyzed in Geographic Information Systems (GIS). Landscape structure was evaluated using dynamic and municipal land cover in 2003 and 2013 as well as applying the Urbanity Index. The Index of Landscape Fragility assessed environmental fragility of the city's landscape. The Environmental Quality Vegetation Index identified and analyzed susceptibility to the effects of ecological components of a particular human activity. The Environmental Quality Index of Water Resources assessed susceptibility of water resources in relation to distance of impact sources. The Vulnerability Index assessed landscape susceptibility due to loss of biodiversity and habitats resulting from fragmentation of native vegetation class. Results showed that direct and indirect forces of change acting on landscape are respectively agricultural activities, mainly correlated to sugarcane cultivation. From 2003 to 2013, there was an increase in the areas occupied by human activities and consequently the reduction of natural areas and loss landscape’s environmental quality with resulting increased fragility as environmental vulnerability. Current developmental trajectories cannot occur without causing impacts, but are not providing benefits the way they should. Loss and degradation of areas of natural vegetation remaining in São Carlos municipality landscape continue growing way. However, the available evidence suggests that the continuation of these fragments in landscape can still provide more economical benefits than those obtained from the conversion and agricultural expansion of land use. The current stage of the city is not the only concern, but also trends – such as the loss of natural areas with increases of anthropogenic uses that solidify over the years, and are discussed in the analysis of the remaining vegetation in the city. The current growth model and generation of impacts are not carried out in favor of the need for concrete development of the city as a whole, but only of certain activities and sectors present in it.
Fator inibitório da migração de macrófagos : envolvimento na regulação cardiovascular em ratos com hipertensão renal
(Universidade Federal de São Carlos, 2015-08-31) Barbosa, Rafaela Moreira; Colombari, Débora Simões de Almeida; https://lattes.cnpq.br/1684467594359403; https://lattes.cnpq.br/0228395782582283
The high blood pressure levels reach about 22% of the world population, increasing the risk factors for coronary disease, heart attack and heart failure. Many studies have tried to understand the causes of hypertension and possible mechanisms to facilitate the treatment of hypertension. The central nervous system seems to play a key role in the development and maintenance of hypertension. Among the various brain areas, we can highlight the role of the nucleus of the solitary tract (NTS), which is the primary site of visceral afferents. The macrophage migration inhibitory factor (MIF) is an intracellular inhibitory regulator of the actions of angiotensin II (ANG II) in the ANG II type 1 receptors. The spontaneously hypertensive rats (SHRs) and the rats with renovascular hypertension 2 kidney, 1 clip (2K1C) exhibit an increased activity of the renin-angiotensin system, increased sympathetic activity and reduced baroreflex function. We recently demonstrated that MIF overexpression in the NTS of SHRs lowers blood pressure of these animals and improved the function of the baroreflex. Therefore, in this study we tested if increased expression of MIF in the NTS of the 2K1C rats could alter the development of hypertension and improve the baroreflex function in these animals. For this, the left renal artery was partially obstructed in male Holtzman rats (150-180 g) using a silver clip (0.2 mm width) to induce 2K1C hypertension (n = 5-10/group) or sham surgery [normotensive rats (NT); n = 5-11/group] was performed. Three weeks after renal clip placement or sham surgery, rats received AAV2-CBA-MIF microinjections into the NTS to increase MIF expression in the area or AAV2-CBA-eGFP, which promoted the expression of GFP (enhanced green protein), which served as a control vector. Arterial pressure and heart rate were recorded by telemetry and baroreflex tests were performed. At the end of the experiments, the brains were harvested for immunohistochemistry RT-PCR. MIF injections into the NTS attenuated the hypertension in 2K1C rats from 2 weeks after viral transfection until the end of the experiment (4 weeks after viral transfection), (2K1C-MIF: 145 ± 7, vs. 2K1C-eGFP: 176 ± 9 mmHg; p < 0.05). MIF into the NTS also improved the reflex bradycardia (2K1C-MIF slope: -1.4 ± 0.3, vs. 2K1C-eGPF slope: -0.41 ± 0.3 bpm/mmHg; p < 0.05) and reflex tachycardia (2K1C-MIF slope: -4.7 ± 0.6, vs. 2K1C-eGPF slope: -1.7 ± 0.3 bpm/mmHg; p < 0.05). Baseline heart rate was decreased in 2K1C-MIF rats. In contrast to 2K1C rats, MIF overexpressed in the NTS in normotensive rats produced no change in arterial pressure neither baroreflex function. As expected, the transduction of MIF in the NTS increased mRNA levels for MIF at the same site (NT-MIF: 3.80 ± 0.97, vs. NT-eGFP: 1.00 ± 0.16 fold change and 2K1C-MIF: 3.53 ± 0.68, vs. 2K1C-eGFP: 0.88 ± 0.09 fold change; p < 0.05). These results suggest that increased expression of MIF in neurons within NTS attenuates the hypertension and improves baroreflex function in 2K1C rats, possibly through anti-ANG II actions.
Saberes tácitos na colheita manual do tomate: estudo de caso a partir da perspectiva da ergonomia
(Universidade Federal de São Carlos, 2015-08-31) Silva, Fabiana Raulino da; Fontes, Andréa Regina Martins; https://lattes.cnpq.br/4848646681792317; https://lattes.cnpq.br/7581031286080881
The variability in agricultural work makes it difficult to be described without considering the complexity of it. Workers in tomato harvesting make the selection of the fruit distinguishing which tomatoes are suitable for harvest, which are not matured yet and which should be discarded, identifying the causes of defects and irregularities. These workers know the quality parameters without having any formal training. This knowledge is fundamental to regulate the strategies of these workers and should be enriched. This research shows a two-year period of immersion in the context of agriculture along with these workers, in order to analyze the importance of tacit knowledge involved in agricultural practice, understanding how this knowledge acquired in practice serve as the basis for all practical labor. As methodology, our study used ergonomics to understand the work of tomato pickers and identify how their knowledge guide the selection of the fruit for harvest. A multiple case study was conducted in three farms through the perspective of ergonomics. We used free observations through semi-structured interview and analysis of the speeches of workers to identify how this knowledge is transmitted and its importance. Our results show that workers must build a mental map, a reference in their mind of how a proper fruit look alike to be harvested. This representation brings several sensorial information that make them choose the fruit through its various features. Even without having received any formal training, the features identified in the fruit are the same listed in formal classification documents. It was noticed that although tacit knowledge is difficult to verbalize, women were able to express in a wider range of words the characteristics of the fruit that guided their actions. Learning of workers is intrinsically related to existing cooperation at work, as they teach each other in mutual aid during the execution of the harvest. For future work, we suggest other studies from ergonomics perspective, suggesting a work transformation to facilitate the sharing of knowledge of these workers.