Condutividade hidráulica e resistência à penetraçao do solo influenciada por diferentes sistemas de manejo

Soil management measures that increase the efficiency of organic matter cycling and maintain favorable soil structure are needed for improving soil quality. On the other hand, soil structure degradation due to inadequate soil management systems is widespread. Among the indicators of soil physical quality, saturated hydraulic conductivity and penetration resistance are thought to be sensitive to soil management system. The aim of this work was to study the influence of soil tillage system and organic fertilization on selected soil physical properties after the first year of treatment. The field work was conducted in Selviria, MS, Brazil on an Oxisol. The experimental design was randomized complete blocks with split-plots, with 12 treatments and 4 repetitions. Tillage treatments included conventional ploughing (CT) and direct drilling (DD). Fertilizer treatments were: 1) manure, 2) manure plus mineral, 3) traditional mineral 4) plant residues of Crotalaria juncea, 5) plant residues of Pennisetum americanum and 6) control plot. The plots were cropped to bean in winter and to cotton in summer, and both cultures were irrigated. After one year no significant differences between treatments in mechanical resistance and porosity were found. However, saturated hydraulic conductivity and infiltration were higher in the conventional tillage treatment at the 0.00-0.10 m depth. Moreover, an improvement in soil physical condition by organic fertilizers was shown.

Tijolos prensados de solo-cimento confeccionados com resíduos de concreto

In this work results are presented of laboratory tests aiming to evaluate the possibility of using concrete wastes in manufactured soil-cement pressed bricks. Tests of characterization of used soil of the composite of this soil with concrete wastes and of the mixtures of soil cement made with this composite were evaluated. According to results of tests carried out with cylindrical specimens and with soil cement pressed bricks, it was verified that the addition of the concrete wastes improved soil cement mechanical properties, favoring the a reduction of the cement consumption, obtaining pressed bricks with a better quality.

Níveis constitutivos de compostos fenólicos podem estar relacionados à resistência da cana-de-açúcar à cigarrinha-das-raízes

The interaction of the leafhopper-of-roots with the sugar cane is still poorly marked and there is little information on resistant varieties. The phenolic compounds are involved in resistance mechanisms of the antibiosis type, but few studies are devoted to the studying role of these compounds in the interaction of plants with sucking insects. The study was conducted to determine how the sugar cane responded to the infestation of Mahanarva fimbriolata in terms of accumulation of phenolic compounds. An experiment was carried out under controlled conditions in a randomized design in a factorial schedule 3 x 2 x 4, with 3 genotypes and sugar cane, 2 levels of nymphs infestation of M. fimbriolata and sampling 4 times, with 4 repetitions. The genotypes SP80-1816 and RB72454 showed higher levels of total phenols when subjected to an infestation of the pest, but the duration of the nymphal stage and mortality of sharpshooters were significantly lower in those varieties, indicating that the increase in the concentration of phenolic compounds may had been caused by death and decay of the roots. It was not observed variation in levels of total phenols in the variety SP83- 5073 subject to an infestation of M. fimbriolata. However, the mortality of the leafhopperof- roots and duration of the stage of nymphs were significantly higher in genotype, indicating the existence of resistance-type antibiosis. Analysis of correlation showed that higher initial levels of phenolic compounds resulting in mortality of the pest can increase the duration of the nymph stage.

Determinação da resistência de Staphylococcus aureus: Um desafio?

The aim of this study was to identify the resistance profile of Staphylococcus aureus strains, in relation to induced clindamycin resistance, and to detect oxacillin resistance by the routine phenotypic methods. The strains were isolated from nasal or lingual swabs taken from healthy adult carriers with no medical history of hospitalization or antibiotic treatment. Eighteen strains were distinguished by the different patterns generated by pulsed field gel electrophoresis (PFGE). Four (22.2%) of these showed sensitivity to clindamycin by the conventional antibacterial susceptibility test, but demonstrated inducible resistance to it by the D-test. One strain (5.6%) was characterized as borderline oxacillin-resistant S. aureus (BORSA), and another (5.6%) as CA MRSA (community-associated methicillin-resistant Staphylococcus aureus). Both of these strains were shown to be cefoxitin susceptible by the disk diffusion test. The polymerase chain reaction (PCR) failed to detect the mecA gene in this last strain and it was thus classified as BORSA. These results show the importance of incorporating the D-test into the routine lab tests for S. aureus inducible clindamycin resistance and also of including the cefoxitin resistance test among the phenotypic methods for MRSA characterization.

Influência da contaminação da dentina por cimentos temporários na resistência da união de sistemas adesivos

Objective: The aim of this study was to assess the bond strength of adhesive systems to dentin contaminated by temporary cements with or without eugenol. Method: Flat dentin surfaces were obtained from twenty-four human third molars. With exception of the control group (n=8), the surfaces were covered with Interim Restorative Material (Caulk Dentsplay, Milford, DE, USA) or Cavit (3M ESPE, St. Paul, MN, USA) and kept in an oven at 37°C for seven days. After removing the cements, the adhesive systems Adper Single Bond (3M ESPE, St. Paul, MN, USA) or Clearfil SE Bond (Kuraray Co. Ltd., Osaka, Japan) were applied in accordance with the manufacturers' recommendations, and then the crowns were constructed in of resin composite. The teeth were sectioned into specimens with a cross-sectional bond area of 0.81mm2, which were submitted to microtensile testing in a mechanical test machine at an actuator speed of 0.5mm/min. The data were analyzed by t- and ANOVA tests, complemented by Tukey tests (α=0.05). Results: For Adper Single Bond (3M ESPE, St. Paul, MN, USA), bond strength did not differ statistically (p>0.05) for all the experimental conditions. For Clearfil SE Bond (Kuraray Co. Ltd., Osaka, Japan), only the Interim Restorative Material (Caulk Dentsplay, Milford, DE, USA) Group showed significantly lower bond strength (30.1 ± 13.8 MPa) in comparison with the other groups; control (38.9 ± 13.5 MPa) and Cavit (3M ESPE, St. Paul, MN, USA) (42.1 ± 11.0 MPa), which showed no significant difference between them. Conclusion: It was concluded that the previous covering of dentin with temporary cement containing eugenol had a deleterious effect on the adhesive performance of the self-etching system only.

Avaliação de Diferentes Compósitos na Resistência à Fratura de Núcleos de Preenchimento

Objective: To evaluate and compare the fracture strength of different composite resins used for core buildup. Method: Thirty-six bovine teeth were decoronated at the cervical third to standardize the length of specimens at 20 mm. Under constant irrigation, the canals were prepared with #5 Largo drills corresponding to the size and diameter of #3 Reforpost fiberglass post. The posts were cemented with Enforce resin sealer, being 16 mm inside the root canal and 4 mm outside the root canal, and the material was light-activated for 30 seconds at each side. The specimens were divided into 3 groups (n=12), in which cores (4 mm diameter and 5 mm high) were prepared from a prefabricated standard with three types of composite resins: Group 1: Z100 (3M), Group 2: Z250 (3M) and Group 3: P60 (3M). The specimens were fixed in a cylindrical device with an adaptor at 45o inclination. This device was adapted to a universal testing machine (EMIC) to simulate the force until fracture of the specimen. Data were subjected to ANOVA (p<0.05). Results: The Z250 resin cores presented the highest mean fracture strength (45.453 kgf), while the mean fracture strengths in Group 1 and Group 3 were 38.014 and 39.506 kgf, respectively. P60 caused the largest number of root fractures. Conclusion: Considering the characteristics and properties of the tested resins, Z250 appears as the most indicated for core buildup.

Dependência estrutural da capacidade de rotação plástic em vigas de concreto armado

Summary In this work the structural dependence of plastic rotation capacity in RC beams is evaluated using the Finite Element Method. The objective is to achieve a better understanding of the non-linear behavior of reinforced concrete members and perform extensive parameter studies, using a rational model developed by Bigaj [1] to analyze the phenomenon of plastic rotation capacity in reinforced concrete members. It is assumed that only bending failure is relevant due to sufficient member resistance against shear and torsion. The paper begins with the physical and theoretical background of the phenomenon of plastic hinge development in RC structures. Special emphasis is laid on the issue of structural dependence of deformation capacity of plastic hinges in RC members. Member size dependence and influence of properties of construction materials were emphasized as well. The essential components of the Bigajs model for calculating the plastic rotation capacity are discussed. The behaviour of the plastic hinge is analysed taking into account the strain localisation in the damage zones of the hinge region. The Fictitious Crack Model (FCM) and the Compressive Damage Zone Model (CDZ) are adopted in a Fracture Mechanics approach to model the behaviour of concrete in tension and compression, respectively. The approach is implemented in FEMOOP, a FEM in-house solver under development, and applied to evaluate ductility in 2D beams. The models were generated with GiD, a pre-processor and post-processor developed by CIMNE, and analyzed with the capabilities implemented in FEMOOP. © Universitat Politècnica de Catalunya, Barcelona, España 2010.

Influência de diferentes sistemas adesivos na resistência de união de pinos de fibra à dentina intrarradicular

Objective: To evaluate the influence of three adhesive systems on the bond strength of fiber post luted to root dentine. The hypothesis was that the bond strength is influenced by the adhesive system. Method: The canals of thirty single-root bovine roots (16mm in length) were prepared using the preparation drill (FGM) until 12mm. 14 mm of each root was embedded with acrylic resin and the specimens were allocated into three groups (n=10), considering the factor adhesive (3 levels): Gr1- Scotchbond Multipurpose Plus (3M ESPE), Gr2- One Step (Bisco) and Gr3- Excite DSC (Ivoclar Vivadent). The adhesive systems were applied using a microbrush, according to the manufacture's recommendations. The fiber posts (White Post DC, FGM) were luted with dual resin cement (All-Cem,FGM). After, the cores with composite resin (Llis, FGM) were made and each set of root/post/core was submitted to the mechanical cycling (Erios, Brazil) (10 6 cycles, 84N, 4 Hz, inclination of 45 o, 37 oC, water). Each specimen was cut in 4 samples (1.8mm in thickness), which were submitted to the push-out test in a universal testing machine (ServoPulser - Shimadzu) (50Kgf, 1mm/min). The data (MPa) were analyzed using ANOVA (1-way) and Tukey test (5%). Results: The factor adhesive (P=0.00352) influenced the bond strength significantly (ANOVA). Gr1 (6.8±3.8 MPa) a presented higher bond strength values than Gr2 (3.1±1.5 MPa) b and similar to Gr3 (4.4±3.3) a,b. Moreover, Gr3 and Gr2 were similar between them (Tukey). The hypothesis was accepted. Conclusion: Based on the results it was concluded that chemical and dual polymerization adhesive system should be used for the adhesive luting fiber post procedures.

Associação do padrão de ingestão lípidica com a qualidade da dieta, resistência insulínica e homocisteinemia em adultos

Objectives: To evaluate the association between the consumption of different dietary fats with the quality of the diet, insulin resistance, and hyperhomocysteinemia in adults. Methods: Cross-sectional study conducted with 624 overweight subjects (73.7% females). Assessments of food intake (24h food recall and health eating index-HEI), anthropometry, and biochemical assays of fasting glucose, insulin (HOMA-IR and β calculus) and homocysteinemia were performed. Results: The low quality of diet was associated with the vegetable oil at 3rd quintile (≥1.5-2.0 servings) showed risk 2.9 times and cholesterol at quintiles 2nd, 3rd, and 4th was 2.0 times. HOMA-IR was higher at 5th quintile of saturated fat (≥10,7% - total caloric value) with risk of 60% and hyperhomocysteinemia the vegetable oil at 3rd quintile (>1.5-2.0 servings) with risk of 12.0 times and 5th (≥3.5 servings) 7.1 times. However, significance disappeared when adjusted for anthropometric variables. Conclusion: Dietary fats were associated with the harm diet quality, insulin resistance, and hyperhomocysteinemia. However, associations are dependant of demographic variables, dietetic, and nutritional state. © 2011 CELOM.

Perfil de resistência a antimicrobianos de Staphylococcus aureus isolados de granjas e frigoríficos de suínos

Staphylococcus aureus are involved in a wide range of clinical problems to swine industry as son in humans. Epidemiological researchs prove his potential to acquire resistantence to antibiotics. Nowadays, methicillin-resistant S. aureus (MRSA) are responsabilized for nosocomial infections and many studies are done because MRSA are spread to extra hospitalar enrivonment and frequentely isolated from domestic animals including pigs. The aim of this study was to determine the presence o S. aureus at swine farms and identify the mecA, icaA and icaD genes and the resistant proflife to antibiotics. Overal, 458 swabs were taked from five pigeris and two slautherhouses. All the samples were placed on Braid - Parker and blood agar follow by biochemical analyses. The suspect colonies were submitted to PCR to confirm the S. aureus species, by the detection of the coa gene, mecA to avaible meticillin-resistant as son to the virulence gens icaA and icaD that can determine slime production. Antibiogram were done to evaluate the response to 11 antibiotics. All pigeris and slautherhouse were positive and 81 (79%) samples were S. aureus positive including four isolates from pigs employeers. The mecA gene was not detected. The icaD gene was most frequent and 41% were positive to both genes. The antibiogram show a lot of samples penicillin and tetraciclin resistant. Most of the samples were multirestant.

Resistência de genótipos de soja ao nematoide reniforme em ambiente controlado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Resistência de genótipos de eucalipto a ceratocystis spp

Eucalyptus is the most important plantation forest species in Brazil. Wilt and canker caused by Ceratocystis fimbriata on eucalyptus were first reported in 1998 in plantations of an E. grandis × E. urophylla hybrid in southern Bahia, Brazil. This work aimed at studying the reaction of different eucalyptus genotypes after inoculation with C. fimbriata isolates, in order to find a possible source of resistance. The study included four isolates of Ceratocystis collected from eucalyptus in different regions. One disc of fungal mycelium with 1-cm-diameter (from colonies growing for 10 days on malt extract agar medium-MEA) was inoculated on the stem of thus injured eucalyptus plants (six months old). A cotton wool moistened with sterile distilled water was wrapped with plastic film. Control plants were inoculated with discs of MEA without fungal colonies. The inoculated plants were kept in a greenhouse. Wilt symptoms were observed 90 days after inoculation. The seedlings were cut in the longitudinal direction of the stem in order to observe the colonization of fungus in the plant xylem. We tested twenty eucalyptus genotypes, but only five showed resistance to all isolates of Ceratocystis, belonging to different species of Eucalyptus: E. urophylla (C2 and C9), E. grandis (C3), E. saligna (C6 and C13) Most E. gramdis genotypes were more susceptible to all four fungal isolates. These results support future studies related to eucalyptus resistance to Ceratocystis.

Variabilidade espacial da resistência mecânica do solo à penetração e umidade do solo em área cultivada com cana-de-açúcar na região de Humaitá, Amazonas, Brasil

The mechanical resistance to penetration (RP) is an attribute indicator of compaction was influenced by soil moisture. The objective of this study was to evaluate the spatial variability of soil resistance to penetration and soil moisture on area under cultivation of sugar cane in the region of Humaitá, Amazonas, Brazil. We conducted a sampling grid of 70x70 m where points were scored at regular intervals of 10 m, a total of 64 points. Soil samples were collected at depths of 0.00 to 0.15 m, 0.15 to 0.30 I 0.30 to 0.45 m for determination of soil moisture and soil resistance to penetration in the field. After analysis of these data analyzes were descriptive statistics and geostatistics. We conclude that all the variables studied showed spatial dependence and range values were higher than stipulated by the sampling grid and the RP and soil moisture showed a spatial relationship where lower values of PR concentrated on smaller values of soil moisture.

Resistência da parede abdominal após a remoção cirúrgica dos músculos retos abdominais: estudos experimental em ratos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da corrente elétrica contínua isolada e da iontoforese transdermal, associada ao zinco, sobre a resistência mecânica e o conteúdo de hidroxiprolina de cicatrizes realizadas na pele de ratos diabéticos aloxânicos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)