Calibração da Reflectometria no Domínio do Tempo (TDR) para a estimativa da concentração da solução no solo

Time Domain Reflectometry (TDR) is a reliable method for in-situ measurements of the humidity and the solution concentration at the same soil volume. Accurate interpretation of electrical conductivity (and soil humidity) measurements may require a specific calibration curve. The primary goal of this work was to establish a calibration procedure for using TDR to estimate potassium nitrate concentrations (KNO3) in soil solution. An equation relating the electrical conductivity measured by TDR and KNO3 concentration was established enabling the use of TDR technique to estimate soil water content and nitrate concentration for efficient fertigation management.

Características físicas e mecânicas de misturas de solo, cimento e casca de arroz

The main objective of this work is the study of the effect of rice husk addition on the physical and mechanical properties of soil-cement, in order to obtain an alternative construction material. The rice husk preparation consisted of grinding, sieving, and the pre-treatment with lime solution. The physical characteristics of the soil and of the rice husk were determined. Different amounts of soil, cement and rice husk were tested by compaction and unconfined compression. The specimens molded according to the treatments applied to the mixtures were subsequently submitted to compression testing and to tensile splitting cylinder testing at 7 and 28 days of age and to water absorption testing. After determining its physical and mechanical characteristics, the best results were obtained for the soil + 12% (cement + rice husk) mixture. The results showed a promising use as an alternative construction material.

Determinação da difusividade efetiva de raiz de chicória

Inulin is a fructooligosacharide found in diverse agricultural products, amongst them garlic, banana, Jerusalem artichoke and chicory root. Inulin generally is used in developed countries, as a substitute of sugar and/or fat due to its characteristics of fitting as functional and dietary food. Chicory root is usually used as source and raw material for commercial extration of inulin. The experiments consisted on drying sliced chicory roots based on a factorial experimental design in a convective dryer whose alows the air to pass perpendicularly through the tray. Effective diffusivity (dependent variable) has been determined for each experimental combination of independent variables (air temperature and velocity). The data curves have been fitted by the solution of the second Fick law and Page's model. Effective difusivity varied from 3.51 x 10-10 m² s-1 to 1.036 x 10-10 m² s-1. It is concluded that, for the range of studied values, air temperature is the only statistically significant variable. So, a first order mathematical model was obtained, representing effective diffusivity behavior as function of air temperature. The best drying condition was correspondent to the trial using the highest drying air temperature.

Modelos de transferência de metal pesado na cana-de-açúcar adubada com composto de lixo urbano

The research approaches recycling of urban waste compost (UWC) as an alternative fertilizer for sugarcane crop and as a social and environmental solution to the solids residuals growth in urban centers. A mathematical model was used in order to know the metal dynamics as decision support tool, aiming to establish of criteria and procedures for UWC's safe use, limited by the amount of heavy metal. A compartmental model was developed from experimental data in controlled conditions and partially checked with field data. This model described the heavy metal transference in the system soil-root-aerial portion of sugarcane plants and concluded that nickel was metal to be concern, since it takes approximately three years to be attenuated in the soil, reaching the aerial portions of the plant at high concentrations. Regarding factors such as clay content, oxide level and soil pH, it was observed that for soil with higher buffering capacity, the transfer of the majority of the metals was slower. This model may become an important tool for the attainment of laws regarding the UWC use, aiming to reduce environment contamination the waste accumulation and production costs.

Produção de alface hidropônica em três ambientes de cultivo

It was proposed to evaluate the hydroponic lettuce production, variety Vera, on inclined benches with channels of 100 mm, and Nutrient Film Technique, as answer to carbon dioxide application and evaporative cooling. There were five cycles of cultivation from March, 20th to April, 17th (C1); from May, 25th to June, 29th (C2); from July, 13th to August, 20th (C3); from August, 27th to October, 10th (C4); from December, 12th to January, 10th (C5). In three greenhouses were tested the following systems: (A1) without evaporative cooling air CO2 aerial injection, (A2) with CO2 aerial injection and without evaporative cooling and (A3) with CO2 aerial injection and pad-fan evaporative cooling system. The fresh and dry mass of leaves in grams, number of leaves and leaf area in square millimeter were evaluated. The completely randomized statistical analysis was used. The cycle C1 were used 48 replications, for cycles C2, C3 and C5 were used 64 replications and C5 were used 24 replications. The results showed that greenhouse with evaporative cooling system and CO2 allow better development and greater lettuce yield. It was possible to conclude that the aerial injection of CO2, in the absence of evaporative cooling system, did not lead increasing the lettuce productivity to most cycles. Bigger lettuce leaf areas were found in periods with higher temperatures.

Estrutura de um curso de taxonomia de campo: o modelo aplicado em Ubatuba, São Paulo

The field activities are essential for the education of a good taxonomist. The most common problems found in field activities are: a) large number of students, b) heterogeneous educational background and unlevelled knowledge of the participants, c) repetitions and tendency of collecting the more evidents life-forms. The causes and consequences of such problems are discussed herein. The proposed solution is a methodology, based on many years of experience in field courses for undergraduate and graduate courses. Topics about the ideal number of participants, area of coverage, period of activity, division of work and the necessary material and equipment are discussed. According to the number of species collected at the same place, this methodology may result in a list of local species with precise information about the life-forms, habitat, common names, frequency, uses, phenology and further information in this kind of work. The results of the aplication of this metodology in a field course held in the region of Ubatuba-SP are presented.

Efeito da temperatura e do teor de umidade na iniciação e desenvolvimento do rizoma de Kohleria eriantha (Benth.) Hanst. (Gesneriaceae)

Kohleria eriantha (Benth.) Hanst is a plant belonging to the family Gesneriaceae, with an underground organ, which is associated with vegetative reproduction. This organ is a rhizome, whose stem bears buds covered with modified leaves that store up starch. In small sections of this rhizome, containing six buds (1.5 to 2.0cm long), only one bud sprouted. The sprouted bud could be differentiated into two morphological pattern: aerial part or rhizome. Sprouting of the rhizome pattern occurred in sections kept on substrate with low water content (1mL of water), or lacking water, whereas sprouting of the aerial part pattern occurred in sections on substrate with high water content (12mL of water). Temperature at 20ºC also stimulated sprouting of the rhizome pattern, regardless of the water volume in the substrate. Sprouting of the rhizome pattern occurred still in sections on substrate to which polyethylene glycol 6000 (PEG) solution was added at the concentrations of 161.2, 235.2 and 340.0g/L, resulting in potentials of -3, -6 and -12 MPa, respectively. Sections kept on substrate with low water content (1 ml of water) showed a reduction in the dry matter content and high osmotic concentration in comparison with those on substrate with high water content. The results obtained revealed that forming of the rhizome pattern was influenced by water content and temperature. It is suggested that sprouting of the rhizome pattern was induced by the low water potential in the sections, when kept on substrate with low water content. Moreover, it was observed that the rhizome buds of Kohleria eriantha showed a high degree of plasticity.

Estilos motivacionais de professores: propriedades psicométricas de um instrumento de avaliação

The purpose of this study was to conduct an exploratory factorial analysis of Problems in School, a teachers' motivational styles evaluation instrument, constructed by Deci et al. The original instrument is in a Likert-scale format with the underlying assumption of the existence of a continuum of four different styles contributing to promote students' autonomy. Translated into portuguese, the instrument was applied to 582 elementary and junior high school teachers from several regions of Brazil. Factorial analyses revealed a solution with four orthogonal distinct factors, the authors' initial supposition (existence of a continuum) was not confirmed. In fact, only two opposite styles (both high promotion of autonomy and of control) corresponded to the Deci et al. original ideas. Problems regarding the validity of the other remaining styles emerged. Data was discussed and a revised version of the scale was developed. Directions for further research were also suggested.

Implante coclear em crianças: a visão dos pais

The objective of this study was to analyze the point of view of parents in relation to the cochlear implant, their level of information concerning the implant, its risks and benefits, and their expectations towards their children's future. Ten parents of deaf children candidate for the cochlear implant at Unicamp's Clinical Hospital were interviewed. Based on a qualitative approach, a content analysis showed that the majority of parents seek the cure for deafness, and consequently, the acquisition of speech with the cochlear implant. For these families, the cochlear implant is seen both as the solution to their children's deafness and as a path for a better future. It has been evidenced that during the acquisition of knowledge about the implant, parents experienced anxiety and anguish when faced with the risks and benefits of the procedure, and the need to choose between performing and not performing the cochlear implant.

Otimização do descascamento químico de raízes do yacon (Polymnia sonchifolia Poepp.)

A full factorial design 2³ was used to evaluate the effect of process variables in chemical peeling of yacon roots, cultivated in Curitiba, State of Paraná. Eleven treatments, with three central points, were done in which they had been evaluated at three different levels of sodium hydroxide solution, % (g/100 mL) [6, 10, 14], temperature of the same solution, °C [70, 80, 90], and residence time in the sodium hydroxide solution, minutes [2, 4, 6]. All the studied variables had affected significantly (p<0.05) the yield of yacon roots subjected to chemical peeling. The variable that most affected the yield was the time of permanence in the sodium hydroxide solution. The mathematical model obtained for the yield (%) was good with R² aj = 0.8497, and non significant lack of fit (p=0.9312).Therefore, the model can be used for predictive purposes. In the central point a satisfactory yield (84% to 87%) with a high percentage of removed peel was obtained (96% to 98%) indicating that the treatment with 10% of sodium hydroxide solution, temperature of 80º C per 4 minutes can be used in the chemical peeling of yacon roots.

Metamorfose planar via métodos Level Set e Particle Level Set para a reconstrução de superfícies tridimensionais

Evolving interfaces were initially focused on solutions to scientific problems in Fluid Dynamics. With the advent of the more robust modeling provided by Level Set method, their original boundaries of applicability were extended. Specifically to the Geometric Modeling area, works published until then, relating Level Set to tridimensional surface reconstruction, centered themselves on reconstruction from a data cloud dispersed in space; the approach based on parallel planar slices transversal to the object to be reconstructed is still incipient. Based on this fact, the present work proposes to analyse the feasibility of Level Set to tridimensional reconstruction, offering a methodology that simultaneously integrates the proved efficient ideas already published about such approximation and the proposals to process the inherent limitations of the method not satisfactorily treated yet, in particular the excessive smoothing of fine characteristics of contours evolving under Level Set. In relation to this, the application of the variant Particle Level Set is suggested as a solution, for its intrinsic proved capability to preserve mass of dynamic fronts. At the end, synthetic and real data sets are used to evaluate the presented tridimensional surface reconstruction methodology qualitatively.

Desidratação osmótica de abacaxi aplicada à tecnologia de métodos combinados

The aim of this research was to optimize osmotic dehydration of pineapple, according to two criteria: maximize water loss and minimize solid gain. The process was made as an application to Combined Methods Technology, in which three preservation factors were combined: water activity, pH and chemical preservatives, all being applied at low levels, in order to get a product resembling non-processed fruit. The experiment was divided into three treatments, being: non-coated pineapple pieces (A), pieces coated with alginate (B) and coated with low-methoxyl pectin (C). Process involved the following main steps: enzymatic inactivation of fruit pieces; in treatments B and C, incorporation of their respective coatings; and osmotic dehydration, in sucrose syrup containing potassium sorbate and citric acid. Optimum conditions, determined from Response Surface Methodology, were the following: dehydration of fruit pieces coated by alginate, at 42-47° C, in sucrose syrup at 66-69° Brix, for 220 to 270 minutes. Results indicated that both coatings significantly affected the mass transfers of the process, reducing solid incorporation and increasing water loss; therefore, increasing weight loss and performance ratio (water loss: solid incorporation) took place. Water activity was not significantly affected by the coatings. The product obtained under optimum conditions was submitted to sensorial evaluation, and presented a good general acceptance. Moulds and yeasts countings indicated good microbiological stability of the product for at least 60 days at 30ºC.

Metamorfose planar via métodos Level Set e Particle Level Set para a reconstrução de superfícies tridimensionais

Evolving interfaces were initially focused on solutions to scientific problems in Fluid Dynamics. With the advent of the more robust modeling provided by Level Set method, their original boundaries of applicability were extended. Specifically to the Geometric Modeling area, works published until then, relating Level Set to tridimensional surface reconstruction, centered themselves on reconstruction from a data cloud dispersed in space; the approach based on parallel planar slices transversal to the object to be reconstructed is still incipient. Based on this fact, the present work proposes to analyse the feasibility of Level Set to tridimensional reconstruction, offering a methodology that simultaneously integrates the proved efficient ideas already published about such approximation and the proposals to process the inherent limitations of the method not satisfactorily treated yet, in particular the excessive smoothing of fine characteristics of contours evolving under Level Set. In relation to this, the application of the variant Particle Level Set is suggested as a solution, for its intrinsic proved capability to preserve mass of dynamic fronts. At the end, synthetic and real data sets are used to evaluate the presented tridimensional surface reconstruction methodology qualitatively.

O uso da mitomicina C em cirurgia combinada

Purpose: To analyze the efficacy and safety of intraope-rative mitomycin C (MMC) in combined procedures (extra-capsular cataract extraction + trabeculectomy). Methods: Twenty-four patients were randomized to either MMC (0.5 mg/ml) (n = 14) or saline solution (n = 10) for 3 minutes during the combined procedure. Results: Twelve months after surgery, mean IOP in the MMC group (13.2 ± 2.9 mmHg) was significantly lower than in the control group (16.3 ± 3.9 mmHg) (p = 0.02). The mean number of medications used during the 12-month follow-up in the control group (1.33 ± 0.5) was significantly higher than in the MMC-treated group (0.5 ± 0.5) (p = 0.005). Life table analysis showed a significantly higher probability of IOP control in the MMC group than in the control group (p < 0.01). Conclusions: Intraoperative MMC is safe and effective in pro-moting a better IOP control and reducing the need for postoperative antiglaucoma medications. We suggest intraope-rative MMC to be routinely employed in combined procedures.

Assessment of ocular surface toxicity after topical instillation of nitric oxide donors

PURPOSE: To evaluate the ocular surface toxicity of two nitric oxide donors in ex vivo and in vivo animal models: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetylcysteine (SNAC) in a hydroxypropyl methylcellulose (HPMC) matrix at final concentrations 1.0 and 10.0 mM. METHODS: Ex vivo GSNO and SNAC toxicities were clinically and histologically analyzed using freshly excised pig eyeballs. In vivo experiments were performed with 20 albino rabbits which were randomized into 4 groups (5 animals each): Groups 1 and 2 received instillations of 150 µL of aqueous HPMC solution containing GSNO 1.0 and 10.0 mM, respectively, in one of the eyes; Groups 3 and 4 received instillations of 150 µL of aqueous HPMC solution-containing SNAC 1.0 and 10.0 mM, respectively, in one of the eyes. The contralateral eyes in each group received aqueous HPMC as a control. All animals underwent clinical evaluation on a slit lamp and the eyes were scored according to a modified Draize eye test and were histologically analyzed. RESULTS: Pig eyeballs showed no signs of perforation, erosion, corneal opacity or other gross damage. These findings were confirmed by histological analysis. There was no difference between control and treated rabbit eyes according to the Draize eye test score in all groups (p>0.05). All formulations showed a mean score under 1 and were classified as non-irritating. There was no evidence of tissue toxicity in the histological analysis in all animals. CONCLUSION: Aqueous HPMC solutions containing GSNO and SNAC at concentrations up to 10.0 mM do not induce ocular irritation.