STOCHASTIC MODEL FOR SIMULATING MAIZE YIELD

Maize is one of the most important crops in the world. The products generated from this crop are largely used in the starch industry, the animal and human nutrition sector, and biomass energy production and refineries. For these reasons, there is much interest in figuring the potential grain yield of maize genotypes in relation to the environment in which they will be grown, as the productivity directly affects agribusiness or farm profitability. Questions like these can be investigated with ecophysiological crop models, which can be organized according to different philosophies and structures. The main objective of this work is to conceptualize a stochastic model for predicting maize grain yield and productivity under different conditions of water supply while considering the uncertainties of daily climate data. Therefore, one focus is to explain the model construction in detail, and the other is to present some results in light of the philosophy adopted. A deterministic model was built as the basis for the stochastic model. The former performed well in terms of the curve shape of the above-ground dry matter over time as well as the grain yield under full and moderate water deficit conditions. Through the use of a triangular distribution for the harvest index and a bivariate normal distribution of the averaged daily solar radiation and air temperature, the stochastic model satisfactorily simulated grain productivity, i.e., it was found that 10,604 kg ha(-1) is the most likely grain productivity, very similar to the productivity simulated by the deterministic model and for the real conditions based on a field experiment.

'Syrah' vine on different rootstocks in winter cycle in the south of Minas Gerais State, Brazil

The objective of this work was to evaluate rootstock influence on agronomical, ecophysiological and qualitative characteristics of 'Syrah' vines managed by double pruning. Grapevines were grafted onto 'SO4', '110 Richter' and '1103 Paulsen' rootstocks and trained in vertical shoot position, with no irrigation. Ecophysiological characteristics, yield and composition of ripe grapes were evaluated in three crop seasons (2007, 2008 and 2010). Rootstocks did not affect pre-dawn water potential, with values close to -0.2 MPa, indicating that there was no soil water deficit at the end of ripening (June). There was also no significant effect of rootstocks on yield. The rootstock '1103 Paulsen' induced lower vegetative growth, lower photosynthetic rate and the best results for berry maturation for crop seasons with lower amount of rainfall. The rootstocks '110 Richter' and 'SO4' showed higher vigor under the meteorological conditions of 2010 and the greatest photosynthetic rates in the same period. Meteorological conditions significantly affected technological and phenolic ripeness, with best results observed in drought years. The '1103 Paulsen' rootstock provides better balance between vigor and yield, increasing grape quality.

Effect of passive ultrassonic instrumentation as a final irrigation protocol on debris and smear layer removal

This study sought to evaluate the efficacy of passive ultrasonic irrigation (PUI) on removing the smear layer and debris from root dentin using scanning electron microscopy (SEM). Twenty-five bovine incisors were manually prepared and divided into three groups according to the final irrigation protocol: EDTA, final irrigation with 12 mL of 17% EDTA for 3 minutes followed by 5 mL of 2.5% NaOCl; EDTA=PUI, final flush with 4 mL of 17% EDTA and PUI for 30 seconds. These procedures were repeated three times to standardize the volume of the irrigant. Control group, after preparation, the specimens were irrigated only with 17 mL of 2.5% NaOCl. The roots were fractured and analyzed using SEM. The intragroup analysis revealed that the EDTA=PUI protocol removed a higher amount of debris at the cervical third (P 5 0.03). The intergroup analysis revealed that EDTA=PUI presented the lowest amount of debris at the cervical third (P 5 0.007). Smear layer scores were higher in the control group compared with the EDTA and EDTA=PUI groups, but only at the cervical third (P 50.02). None of the final irrigant protocols completely removed the smear layer and debris. EDTA=PUI only improved the removal of debris at the cervical third.

Optimizing endodontic irrigation: advantages of negative apical pressure technology

FAPESP #2010/16002-4

Economic viability of retrofiting emitters in center pivot irrigation systems

Although several studies have been conducted to evaluate the uniformity of water application under center pivot irrigation systems, there are few studies concerning the economic perspective of such coefficient. The aim of this study is to present a methodology to accomplish an economic analysis as support for the decision-making to retrofit emitters in center pivot irrigation systems, and to attribute an economic meaning to the uniformity coefficient of water application taking into account the response function productivity to the amount of water applied and the sale price of the crops. In the hypothetic calculation example considering the variation of revenue of potato crop under center pivot irrigation system, it was verified that the area with uniformity coefficient of water application of 90% brought an income increase of BR$ 1,992.00, considering an area about 1,0 ha. Thus, it can be concluded that the methodology presented has met the objectives proposed in the study and made it possible to attribute an economical meaning to the coefficient of water uniformity application.

Economic optimization method to design telescope irrigation of multiples outlets

In this study is presented an economic optimization method to design telescope irrigation laterals (multidiameter) with regular spaced outlets. The proposed analytical hydraulic solution was validated by means of a pipeline composed of three different diameters. The minimum acquisition cost of the telescope pipeline was determined by an ideal arrangement of lengths and respective diameters for each one of the three segments. The mathematical optimization method based on the Lagrange multipliers provides a strategy for finding the maximum or minimum of a function subject to certain constraints. In this case, the objective function describes the acquisition cost of pipes, and the constraints are determined from hydraulic parameters as length of irrigation laterals and total head loss permitted. The developed analytical solution provides the ideal combination of each pipe segment length and respective diameter, resulting in a decreased of the acquisition cost.

Economic analysis for oregano under irrigation considering economic risk factors

The oregano is a plant, rich in essential oil and very used as spice in the preparation of foods. The objective of this paper was to analyze the viability of irrigation for oregano in Presidente Prudente, São Paulo state, Brazil, including economic risk factors, their effect on irrigation total cost, as well as the different pumping kinds. The Monte Carlo simulation was utilized to study the economic factors: fixed cost, labor, maintenance, pumping and water. The use of irrigation for the oregano in the region of Presidente Prudente is indicated because of its economic feasibility and the reduced risks. The average values of the benefit/cost for all water depths tested were higher than 1, indicating viability. The use of irrigation promoted lower risks compared to the non irrigated crop. The micro irrigation system presented greater sensitivity to changes of prices of the equipment associated to the variation of the useful life of the system. The oregano selling price was the most important factor involved in annual net profit. The water cost was the factor of lesser influence on the total cost. Due to the characteristic of high drip irrigation frequency there was no difference between the tariffs based in use hour of electric energy classified as green and blue, which are characterized by applying different rates on the energy consumption and demand according to the hours of day and times of the year. For the studied region it was recommended drip irrigation water management of oregano with the daily application of 100% of pan evaporation Class A using electric motor with tariffs blue or green.

Effect of sodium hypochlorite and edta irrigation, individually and in alternation, on dentin microhardness at the furcation area of mandibular molars

The aim of this study was to evaluate the effect of irrigation regimens on dentin microhardness at the furcation area of mandibular molars, using sodium hypochlorite and ethylenediaminetetraacetic acid (EDTA), individually and in alternation. The occlusal surface and the roots of 20 non-carious extracted human permanent mandibular molars were cut transversally and discarded. The tooth blocks were embedded in acrylic resin and randomly assigned to 4 groups (n=5) according to the irrigating regimens: 1% NaOCl solution, 17% EDTA solution, 1% NaOCl and 17% EDTA and distilled water (control). Knoop microhardness of dentin at the furcation area was evaluated. Data were analyzed using one-way ANOVA and Tukey's multiple comparison tests (α=0.05). The results of this study indicated that all irrigation solutions, except for distilled water (control), decreased dentin microhardness. EDTA did not show a significant difference with NaOCl/EDTA (p>0.05), but showed a significant difference with NaOCl (p<0.01). EDTA and NaOCl/EDTA showed a maximum decrease in microhardness. The 17% EDTA solution, either alone or in combination with 1% NaOCl reduced significantly dentin microhardness at the furcation area of mandibular molars.

Performance and radial distribution profiles of a variable flow rate sprinkler developed for precision irrigation

Variable rate sprinklers (VRS) have been developed to promote localized water application of irrigated areas. In Precision Irrigation, VRS permits better control of flow adjustment and, at the same time, provides satisfactory radial distribution profiles for various pressures and flow rates are really necessary. The objective of this work was to evaluate the performance and radial distribution profiles of a developed VRS which varies the nozzle cross sectional area by moving a pin in or out using a stepper motor. Field tests were performed under different conditions of service pressure, rotation angles imposed on the pin and flow rate which resulted in maximal water throw radiuses ranging from 7.30 to 10.38 m. In the experiments in which the service pressure remained constant, the maximal throw radius varied from 7.96 to 8.91 m. Averages were used of repetitions performed under conditions without wind or with winds less than 1.3 m s-1. The VRS with the four stream deflector resulted in greater water application throw radius compared to the six stream deflector. However, the six stream deflector had greater precipitation intensities, as well as better distribution. Thus, selection of the deflector to be utilized should be based on project requirements, respecting the difference in the obtained results. With a small opening of the nozzle, the VRS produced small water droplets that visually presented applicability for foliar chemigation. Regarding the comparison between the estimated and observed flow rates, the stepper motor produced excellent results.

Comparison of child self-reports and parent proxy-reports on quality of life of children with attention deficit hyperactivity disorder

Abstract Background Attention deficit hyperactivity disorder (ADHD) is a neurobiological condition that affects 3%–7% of the pediatric population and significantly compromises the quality of life (QoL) of these individuals. The aim of the current study was to compare child self-reports and parent proxy reports on the QoL of children with ADHD. Methods Forty-five children with ADHD, combined type, aged 8–12 years without comorbidities, were compared with 43 typically developing children. PedsQL™ 4.0 (Pediatric QoL Inventory™) Generic Core Scales (physical, emotional, social, and school functioning) were completed by families and children self-reporting their health-related QoL. Results Children with ADHD reported themselves significantly lowered their PedsQL™ scores on all dimensions in comparison to typically developing children. Statistically significant differences were observed in social functioning (p = 0.010), school functioning (p <0.001), psychosocial health (p <0.001), and total score (p = 0.002). The physical functioning and emotional functioning dimensions did not differ significantly between groups, with p = 0.841 and p = 0.070, respectively. Parents of children with ADHD also reported lower PedsQL™ scores, with statistically significant differences in all dimensions. The relationship between child self-reports and parent proxy reports indicated that there is greater agreement among children with ADHD, except for the school functioning. Conclusions This suggests that children with the disorder and their parents have a perception of the functional limitations the disorder brings. It is therefore important to undertake studies to verify the QoL in children with ADHD that aim to provide and measure the scope of the well-being of these children.

Petrography and sedimentology of aeolian sands: a tool for diagnose the sedimentary deficit in La Graciosa island (Natural Park of Archipielago Chinijo, Canary Islands, Spain).

[EN] Petrography and sedimentology of aeolian sands: a tool for diagnose the sedimentary deficit in La Graciosa island (Natural Park of Archipielago Chinijo, Canary Islands, Spain).

The outcrop of the underlying substratum of the Maspalomas dune field (Gran Canaria, Canary Islands): a sing of a sedimentary deficit

The outcrop of the underlying substratum of the Maspalomas dune field (Gran Canaria, Canary Islands): a sing of a sedimentary deficit