Dynamics of foraging and recruitment behavior in the Asian subterranean termite Coptotermes gestroi (Rhinotermitidae)

The present study investigated the trail-following behavior of the subterranean termite Coptotermes gestroi (Wasmann Rhinotermitidae) under laboratory conditions. The results showed that workers were the first to initiate the exploration to the food source. When food was discovered they returned to the nest laying a trail for recruiting nestmates to the food source. In this situation, workers always traveled significantly faster when returning from the arenas. Both workers and soldiers were recruited to the food source; however, the soldier/worker proportion was higher during the first phase of the recruitment. When no food was available, the number of recruited nestmates and the speed on their way back to the nest were significantly lower. The results also showed that scout foragers always laid trail pheromones when entering into unknown territories, and that chemical signals found in the food could induce workers of C. gestroi to increase their travel speed. Copyright © 2012 Alberto Arab et al.

Estimating hardness of eucalyptus wood with a portable hardness tester

More than 80% of the 29600 km of the Brazilian railroad mesh employs wooden sleepers. The problem of hard availability of native wood for this purpose leads to the alternative use of reforestation species to produce sleepers. Considering the great difficulty to, in field condition, evaluate characteristics that are of major importance to define its suitability to sleeper production the Research Group on Forest Products from FCA/UNESP - Brazil had developed equipment for field evaluation of hardness in wood - Portable Hardness Tester. This paper reports the functional validation tests, performed with different species of Eucalyptus. Results revealed the equipment great functionality, easy-to-use characteristics and applicability to Eucalyptus wood. Moderate to strong relationships between laboratory and validated values of hardness were found. The best validation model was obtained using the data provided by the experimental dispositive 3 (R2=0.74 and SSE= 7.71 kJ/m2) while the experimental dispositive 1 gave the worse validation (R2=0.55 and SSE= 13.46 kJ/m2).

Chemical properties and decay resistance of eucalyptus grandis wood from steamed logs

The objective of this study was evaluate the effect of the log steaming on the chemical properties and decay resistance of Eucalyptus grandis wood. Logs with diameter between 20 and 22 cm were studied. Half of logs were kept in its on original condition, and the other half was steamed at 90°C for 13 hours. The holocellulosc, Klason lignin, total extractives content and the weight loss caused by the decay fungus Pycnoporus sanguineous were characterized. The results showed that the log steaming of E. grandis wood cause: (l)a significantly decreased in holocellulose content; (2) an increase of 4.8% and 4.4% in total extractives and lignin content, respectively; and (3) a decrease in its durability against the decay fungus P. sanguineus in order of 13.03%. Copyright © (2012) by WCTE 2012 Committee.

Functional nanostructured catalysts based on the niobates to the dry methane reforming and ethylene homologation reactions

Catalytic activity and selectivity of niobate-based nanostructured materials were investigated. Dry methane reforming (DMR) and ethylene homologation reaction (EHR) were selected as test reactions. KSr 2Nb5O15, Sr2NaNb5O 15 and NaSr2(NiNb4)O15 δ niobate powders were prepared by the high energy ball milling method and calcined in a reductor atmosphere. N2 adsorption isotherms, X-ray diffraction and infrared spectroscopy characterization was performed. Hydrogen pretreated niobates showed from low to moderate catalytic initial activity in DMR's test, nevertheless the materials were deactivated rapidly and the kinetic parameters associated to deactivation were estimated. Otherwise, non-treated catalysts showed a high initial activity in EHR's test and KSr2Nb 5O15 catalyst requires 24 h to the total deactivation with a high selectivity to form propylene. A reaction mechanism to the propylene formation is discussed. © 2012 Elsevier Ltd. All rights reserved.

Shaping competitiveness in the Chilean wood-processing industry

Includes bibliography

Bond strength of adhesive systems with different solvents to dry and wet dentin

Aim: This study evaluates bond strength between dentin and composite using adhesives with different solvents to dry and wet dentin. Materials and methods: Ninety bovine incisors were used; the vestibular surfaces were worn by the exposure of an area with a diameter of 4 mm of dentin. The specimens were divided into 6 groups, according to the type of adhesive used and hydratation stals: Group SB-wet: Single Bond 2 in wet dentin, Group SBdry: Single Bond 2 in dry dentin, Group SL-wet: Solobond M in wet dentin, Group SL-dry: Solobond M in dentin dry. Group XPwet: XP Bond in wet dentin, Group XP-dry: XP Bond in dentin dry. They were cut to obtain specimens in the shape of stick with 1 × 1 mm and subjected to microtensile test in universal testing machine with a cross speed of 1mm/min. The data were analyzed with ANOVA and Tukey's tests (5%). Results: ANOVA showed significant differences for surface treatment and interaction, but no difference was found for adhesive factor. The Tukey's test showed that the samples with wet dentin shown higher values of bond strength. Conclusion: The adhesive did not influence in the bond strength. The groups with wet dentin showed higher values of bond strength than groups with dry dentin.

Effects of dentin dry/moist condition on the immediate adhesive performance of different solvent-based etch-and-rinse adhesivesystems

Purpose: The purpose of this research was to analyze and measure, under optical microscopy, the hybrid layer thickness and resin tags length, as well as the microtensile bond strength of two conventional adhesive systems when applied to dry and moist dentinal substrate. Methods: Thirty-two extracted human molars were randomly distributed into four groups according to the adhesive systems (XP Bond and Prime&Bond 2.1) and moisture condition (dry and moist). In Groups I and II, XP adhesive system was applied on dry and moist dentin, respectively; while Groups III and IV received PB adhesive system, in the same way as was done in Groups I and II, respectively. After adhesive and restorative procedures, all specimens were sectioned along their long axes; one hemi-tooth sample was subjected to the microtensile bond strength test while the other was decalcified and serially sectioned into six micron thick slices and sequentially mounted on glass slides. These sections were stained by the Brown and Brenn method for posterior analysis and measurement of the hybrid layer and resin tags under a light microscope with a micrometric ocular 40/075. Results: Data were analyzed using two-way ANOVA and Tukey's test (α=0.05). For the variable hybrid layer thickness, XP showed no significant differences between dry and moist dentin (5.2 μm and 5.5 μm, respectively), but for PB, hybrid layer was significantly thicker for moist (4.0 μm) than for dry dentin (3.0 μm). For the variable resin tags length XP showed 17.9 μm length for dry dentin and 20.8 μm for moist dentin; PB 11.7 μm for dry and 12.69 μm for moist dentin;there was no significant differences between them, independent of the moisture condition. For the variable microtensile bond strength, XP showed 38.0 MPa for dry dentin and 44.5 MPa for moist dentin; and PB showed 22.7 MPa for dry dentin and 20.8 MPa for dry dentin no significant difference was observed between moist and dry dentin for XP (p=0.2) and PB (p=0.7), but XP was presented significantly higher bond strength values than PB in both moisture conditions (p=0.003 for dry and p=0.002 for moist). Conclusion: The two-step butanol-based etch-and-rinse adhesive XP Bond presented a superior behavior with regard to the hybrid layer thickness, length of resin tags and bond strength to dry and moist dentin substrates when compared with two-step acetone-based adhesive system Prime&Bond2.1. © 2013 Elsevier Ltd.

Anatomical study of the retroarticular process in dry human skulls

Introduction: The retroarticular process is a bony prominence formed by the thickening of the lateral border of the mandibular fossa, forming the posterior wall of the temporomandibular joint. Since little is known and discussed about the retroarticular process, our aim was to study its presence, shape and size, relating these findings to the shape of the skulls according to the horizontal cephalic index. Materials and Methods: We used 400 dry human skulls of the Institute of Science and Technology - UNESP Anatomy Laboratory. Each skull was classified in brachycranics, mesocranics or dolichocranics, and then positioned on a craneostat to measure the height of the retroarticular process from its lower extremity to the auriculo-orbital plane. The width was obtained by measuring the base of the process on its longer lateral axis. Results: The retroarticular process was found bilaterally in 397 skulls (99.25%). All the processes were classified into the following shapes: pyramidal (35.55%), tubercular (31.78%), mammilar (20.73%), crest-like (9.05%) and molar shape (2.89%); 254 skulls (63.50%) showed the same type of process at the right and left sides (Kappa=0.496, moderate agreement). The average height and width were 5.28 mm and 12.81 mm, respectively. Conclusion: The retroarticular process was found in almost all the skulls examined. There are no significant evidences about the relationship among the presence, shape and size of the retroarticular process and the shape of the skulls according to the horizontal cephalic index. However, our findings led us to infer that there would be a functional relationship between the process and the temporomandibular joint.

Source-driven remobilizations of nutrients within stem wood in Eucalyptus grandis plantations

Nutrient remobilizations in tree ligneous components have been little studied in tropical forests. A complete randomized block design was installed in Brazilian eucalypt plantations to quantify the remobilizations of phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sodium (Na) within stem wood. Three treatments were studied: control with neither K nor Na addition (C), 3 kmol ha-1 K applied (+K), and 3 kmol ha-1 Na applied (+Na). Biomass and nutrient contents were measured in the stem wood of eight trees destructively sampled at 1, 2, 3 and 4 years after planting in each treatment and annual rings were localized on discs of wood sampled every 3 m in half of the trees. Chemical analyses and wood density measurements were performed individually for each ring per level and per tree sampled. Nutrient remobilizations in annual rings were calculated through mass balance between two successive ages. Our results show that nutrient remobilizations within stem wood were mainly source-driven. Potassium and Na additions largely increased their concentration in the outer rings as well as the amounts remobilized in the first 2 years after the wood formation. The amount of Na remobilized in annual rings was 15 % higher in +Na than in +K the fourth year after planting despite a 34 % higher production of stem wood in +K leading to a much higher nutrient sink. A partial substitution of K by Na in the remobilizations within stem wood might contribute to enhancing Eucalyptus grandis growth in K-depleted soils. © 2013 Springer-Verlag Berlin Heidelberg.

Prospects for the use of municipal tree pruning wastes in particleboard production

The purpose of this study was to evaluate the physical and mechanical properties of particleboard made with pruning wastes from Ipê (Tabebuia serratifolia) and Chapéu-de-Sol (Terminalia catappa) trees. Particleboards were prepared with both wood species, using all the material produced by grinding the pruning wastes. The particleboards had dimensions of 45×45 cm, a thickness of approximately 11.5 mm and an average density of 664 kg/m3. A urea-formaldehyde adhesive was used in the proportion of 12% of the dry particle mass. The particleboards were pressed at a temperature of 130 C for 10 mins. The physical and mechanical properties analyzed were density, moisture content, thickness swelling, percentage of lignin and cellulose, modulus of resilience, modulus of elasticity and tensile strength parallel to the grain, accordingly to the standards NBR 14810 and CS 236-66 (1968). The particleboards were considered to be of medium density. The particle size significantly affected the static bending strength and tensile strength parallel to the grain. Ipê presented better results, demonstrating a potential for the production and use of particleboard made from this species. © The Author(s) 2013.

Aquatic Exercise is as Effective as dry Land Training to Blood Pressure Reduction in Postmenopausal Hypertensive Women

Background and Purpose: The evidence of the benefits from regular physical activity to hypertensives is based on dry land training studies. Therefore, the aim of this study is to compare the effect of aquatic exercise with dry land training on hypertensive women. Methods: This is a randomized controlled study with 52 post-menopausal hypertensive women. The patients were randomly allocated in three groups: water aerobic training group (n=19), dry land aerobic training group (n=19) and a non-intervention control group (n=14). The training protocol was performed by 12weeks. Results: There were no differences among the three groups concerning basal blood pressure (BP) and biochemical variables. In water group, there was a statistically significant reduction of systolic BP from 136±16mmHg at zero week to 124±18mm Hg at 11th week and 124±15mmHg at 12th week. In dry land training group, there was a statistically significant reduction of systolic BP from 138±15mmHg at zero week to 125±10mmHg at 7th week, 127±10mmHg at 10th week and 126±9mmHg at 12th week. The control group presented no change in any of the assessed variables. No changes were carried out in any antihypertensive medications during study. Discussion: This is a randomized controlled study that demonstrates the antihypertensive efficacy of aerobic aquatic exercise. © 2013 John Wiley & Sons, Ltd.

Comparative study of the life cycle assessment of particleboards made of residues from sugarcane bagasse (Saccharum spp.) and pine wood shavings (Pinus elliottii)

This paper presents a research on the environmental impacts of particleboards produced from wastes, based on a comparative Life Cycle Assessment study. The particleboards were manufactured in laboratorial scale from the following residues: sugarcane bagasse (Saccharum spp.) and pine wood shavings (Pinus elliottii). The study was developed following the methodological guidelines of ISO 14040. The functional unit adopted was the m2 of the particleboards produced and the impacts were evaluated by the Environmental Development of Industrial Products method. The results indicated that pine particleboard present the highest environmental impact potential. Our findings suggested that the factors that mostly aggravated the environmental impacts were: the distance between the raw materials and the production site, and formaldehyde emissions (FE). The first is related to the combustion of fossil fuel during the acquisition of raw material, which achieved the values of 2185.94 g/m2 for consumption of non-renewable resources for pine particleboard and 893.53 g/m2 for bagasse particleboard. The second is related to the use of urea-formaldehyde resin, responsible for the FE into the air during production. The FE is accountable for the contamination of approximately 7,800,000.00 m3 of air per m2 of particleboard produced, and was the factor with the greatest impact in human toxicity potential. © 2013 Elsevier Ltd. All rights reserved.

Estimativa do tempo de vaporização das toras e sua implicação no desdobro e na secagem da madeira de Eucalyptus grandis

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

Avaliação energética da secagem combinada de milho na região de Pedrinhas Paulista, SP

Pós-graduação em Agronomia (Energia na Agricultura) - FCA