New methods to quantify NH3 volatilization from fertilized surface soil with urea

Gaseous N losses from soil are considerable, resulting mostly from ammonia volatilization linked to agricultural activities such as pasture fertilization. The use of simple and accessible measurement methods of such losses is fundamental in the evaluation of the N cycle in agricultural systems. The purpose of this study was to evaluate quantification methods of NH3 volatilization from fertilized surface soil with urea, with minimal influence on the volatilization processes. The greenhouse experiment was arranged in a completely randomized design with 13 treatments and five replications, with the following treatments: (1) Polyurethane foam (density 20 kg m-3) with phosphoric acid solution absorber (foam absorber), installed 1, 5, 10 and 20 cm above the soil surface; (2) Paper filter with sulfuric acid solution absorber (paper absorber, 1, 5, 10 and 20 cm above the soil surface); (3) Sulfuric acid solution absorber (1, 5 and 10 cm above the soil surface); (4) Semi-open static collector; (5) 15N balance (control). The foam absorber placed 1 cm above the soil surface estimated the real daily rate of loss and accumulated loss of NH3N and proved efficient in capturing NH3 volatized from urea-treated soil. The estimates based on acid absorbers 1, 5 and 10 cm above the soil surface and paper absorbers 1 and 5 cm above the soil surface were only realistic for accumulated N-NH3 losses. Foam absorbers can be indicated to quantify accumulated and daily rates of NH3 volatilization losses similarly to an open static chamber, making calibration equations or correction factors unnecessary.

Multi-objective analysis of impacts of distributed generation placement on the operational characteristics of networks for distribution system planning

Recent advances in energy technology generation and new directions in electricity regulation have made distributed generation (DG) more widespread, with consequent significant impacts on the operational characteristics of distribution networks. For this reason, new methods for identifying such impacts are needed, together with research and development of new tools and resources to maintain and facilitate continued expansion towards DG. This paper presents a study aimed at determining appropriate DG sites for distribution systems. The main considerations which determine DG sites are also presented, together with an account of the advantages gained from correct DG placement. The paper intends to define some quantitative and qualitative parameters evaluated by Digsilent (R), GARP3 (R) and DSA-GD software. A multi-objective approach based on the Bellman-Zadeh algorithm and fuzzy logic is used to determine appropriate DG sites. The study also aims to find acceptable DG locations both for distribution system feeders, as well as for nodes inside a given feeder. (C) 2010 Elsevier Ltd. All rights reserved.

PCA Tomography: how to extract information from data cubes

Astronomy has evolved almost exclusively by the use of spectroscopic and imaging techniques, operated separately. With the development of modern technologies, it is possible to obtain data cubes in which one combines both techniques simultaneously, producing images with spectral resolution. To extract information from them can be quite complex, and hence the development of new methods of data analysis is desirable. We present a method of analysis of data cube (data from single field observations, containing two spatial and one spectral dimension) that uses Principal Component Analysis (PCA) to express the data in the form of reduced dimensionality, facilitating efficient information extraction from very large data sets. PCA transforms the system of correlated coordinates into a system of uncorrelated coordinates ordered by principal components of decreasing variance. The new coordinates are referred to as eigenvectors, and the projections of the data on to these coordinates produce images we will call tomograms. The association of the tomograms (images) to eigenvectors (spectra) is important for the interpretation of both. The eigenvectors are mutually orthogonal, and this information is fundamental for their handling and interpretation. When the data cube shows objects that present uncorrelated physical phenomena, the eigenvector`s orthogonality may be instrumental in separating and identifying them. By handling eigenvectors and tomograms, one can enhance features, extract noise, compress data, extract spectra, etc. We applied the method, for illustration purpose only, to the central region of the low ionization nuclear emission region (LINER) galaxy NGC 4736, and demonstrate that it has a type 1 active nucleus, not known before. Furthermore, we show that it is displaced from the centre of its stellar bulge.

Antimicrobial activity in the tick Rhipicephalus (Boophilus) microplus eggs: Cellular localization and temporal expression of microplusin during oogenesis and embryogenesis

Arthropods display different mechanisms to protect themselves against infections, among which antimicrobial peptides (AMPs) play an important role, acting directly against invader pathogens. We have detected several factors with inhibitory activity against Candida albicans and Micrococcus luteus on the surface and in homogenate of eggs of the tick Rhipicephalus (Boophilus) microplus. One of the anti-M. luteus factors of the egg homogenate was isolated to homogeneity. Analysis by electrospray mass spectrometry (ESI-MS) revealed that it corresponds to microplusin, an AMP previously isolated from the cell-free hemolymph of X (B.) microplus. Reverse transcription (RT) quantitative polymerase chain reactions (qPCR) showed that the levels of microplusin mRNA gradually increase along ovary development, reaching an impressive highest value three days after the adult females have dropped from the calf and start oviposition. Interestingly, the level of microplusin mRNA is very low in recently laid eggs. An enhance of microplusin gene expression in eggs is observed only nine days after the onset of oviposition, achieving the highest level just before the larva hatching, when the level of expression decreases once again. Fluorescence microscopy analysis using an anti-microplusin serum revealed that microplusin is present among yolk granules of oocytes as well as in the connecting tube of ovaries. These results, together to our previous data. suggest that microplusin may be involved not only in protection of adult female hemocele, but also in protection of the female reproductive tract and embryos, what points this AMP as a considerable target for development of new methods to control R. (B.) microplus as well as the vector-borne pathogens. (c) 2009 Elsevier Ltd. All rights reserved.

A novel approach for distributed application scheduling based on prediction of communication events

The evolution of commodity computing lead to the possibility of efficient usage of interconnected machines to solve computationally-intensive tasks, which were previously solvable only by using expensive supercomputers. This, however, required new methods for process scheduling and distribution, considering the network latency, communication cost, heterogeneous environments and distributed computing constraints. An efficient distribution of processes over such environments requires an adequate scheduling strategy, as the cost of inefficient process allocation is unacceptably high. Therefore, a knowledge and prediction of application behavior is essential to perform effective scheduling. In this paper, we overview the evolution of scheduling approaches, focusing on distributed environments. We also evaluate the current approaches for process behavior extraction and prediction, aiming at selecting an adequate technique for online prediction of application execution. Based on this evaluation, we propose a novel model for application behavior prediction, considering chaotic properties of such behavior and the automatic detection of critical execution points. The proposed model is applied and evaluated for process scheduling in cluster and grid computing environments. The obtained results demonstrate that prediction of the process behavior is essential for efficient scheduling in large-scale and heterogeneous distributed environments, outperforming conventional scheduling policies by a factor of 10, and even more in some cases. Furthermore, the proposed approach proves to be efficient for online predictions due to its low computational cost and good precision. (C) 2009 Elsevier B.V. All rights reserved.

Study of the carbon dioxide chemical fixation-activation by guanidines

Fixation of CO(2) is one of the most important priorities of the scientific community dedicated to reduce global warming. In this work, we propose new methods for the fixation of CO2 using the guanidine bases tetramethylguanidine (TMG) and 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]-pyrimidine (TBD). In order to understand the reactions occurring during the CO(2) fixation and release processes, we employed several experimental methods, including solution and solid-state NMR, FTIR, and coupled TGA-FTIR. Quantum mechanical NMR calculations were also carried out. Based on the results obtained, we concluded that CO(2) fixation with both TMG and TBD guanidines is a kinetically reversible process, and the corresponding fixation products have proved to be useful as transcarboxylating compounds. Afterward, CO(2) thermal releasing from this fixation product with TBD was found to be an interesting process for CO(2) capture and isolation purposes. (C) 2008 Elsevier Ltd. All rights reserved.

Relative entropy measures applied to healthy and pathological voice characterization

Nowadays, noninvasive methods of diagnosis have increased due to demands of the population that requires fast, simple and painless exams. These methods have become possible because of the growth of technology that provides the necessary means of collecting and processing signals. New methods of analysis have been developed to understand the complexity of voice signals, such as nonlinear dynamics aiming at the exploration of voice signals dynamic nature. The purpose of this paper is to characterize healthy and pathological voice signals with the aid of relative entropy measures. Phase space reconstruction technique is also used as a way to select interesting regions of the signals. Three groups of samples were used, one from healthy individuals and the other two from people with nodule in the vocal fold and Reinke`s edema. All of them are recordings of sustained vowel /a/ from Brazilian Portuguese. The paper shows that nonlinear dynamical methods seem to be a suitable technique for voice signal analysis, due to the chaotic component of the human voice. Relative entropy is well suited due to its sensibility to uncertainties, since the pathologies are characterized by an increase in the signal complexity and unpredictability. The results showed that the pathological groups had higher entropy values in accordance with other vocal acoustic parameters presented. This suggests that these techniques may improve and complement the recent voice analysis methods available for clinicians. (C) 2008 Elsevier Inc. All rights reserved.

New prediction methods for CO2 evaporation inside tubes: Part I - A two-phase flow pattern map and a flow pattern based phenomenological model for two-phase flow frictional pressure drops

An updated flow pattern map was developed for CO2 on the basis of the previous Cheng-Ribatski-Wojtan-Thome CO2 flow pattern map [1,2] to extend the flow pattern map to a wider range of conditions. A new annular flow to dryout transition (A-D) and a new dryout to mist flow transition (D-M) were proposed here. In addition, a bubbly flow region which generally occurs at high mass velocities and low vapor qualities was added to the updated flow pattern map. The updated flow pattern map is applicable to a much wider range of conditions: tube diameters from 0.6 to 10 mm, mass velocities from 50 to 1500 kg/m(2) s, heat fluxes from 1.8 to 46 kW/m(2) and saturation temperatures from -28 to +25 degrees C (reduced pressures from 0.21 to 0.87). The updated flow pattern map was compared to independent experimental data of flow patterns for CO2 in the literature and it predicts the flow patterns well. Then, a database of CO2 two-phase flow pressure drop results from the literature was set up and the database was compared to the leading empirical pressure drop models: the correlations by Chisholm [3], Friedel [4], Gronnerud [5] and Muller-Steinhagen and Heck [6], a modified Chisholm correlation by Yoon et al. [7] and the flow pattern based model of Moreno Quiben and Thome [8-10]. None of these models was able to predict the CO2 pressure drop data well. Therefore, a new flow pattern based phenomenological model of two-phase flow frictional pressure drop for CO2 was developed by modifying the model of Moreno Quiben and Thome using the updated flow pattern map in this study and it predicts the CO2 pressure drop database quite well overall. (C) 2007 Elsevier Ltd. All rights reserved.

New prediction methods for CO2 evaporation inside tubes: Part II - An updated general flow boiling heat transfer model based on flow patterns

Corresponding to the updated flow pattern map presented in Part I of this study, an updated general flow pattern based flow boiling heat transfer model was developed for CO2 using the Cheng-Ribatski-Wojtan-Thome [L. Cheng, G. Ribatski, L. Wojtan, J.R. Thome, New flow boiling heat transfer model and flow pattern map for carbon dioxide evaporating inside horizontal tubes, Int. J. Heat Mass Transfer 49 (2006) 4082-4094; L. Cheng, G. Ribatski, L. Wojtan, J.R. Thome, Erratum to: ""New flow boiling heat transfer model and flow pattern map for carbon dioxide evaporating inside tubes"" [Heat Mass Transfer 49 (21-22) (2006) 4082-4094], Int. J. Heat Mass Transfer 50 (2007) 391] flow boiling heat transfer model as the starting basis. The flow boiling heat transfer correlation in the dryout region was updated. In addition, a new mist flow heat transfer correlation for CO2 was developed based on the CO2 data and a heat transfer method for bubbly flow was proposed for completeness sake. The updated general flow boiling heat transfer model for CO2 covers all flow regimes and is applicable to a wider range of conditions for horizontal tubes: tube diameters from 0.6 to 10 mm, mass velocities from 50 to 1500 kg/m(2) s, heat fluxes from 1.8 to 46 kW/m(2) and saturation temperatures from -28 to 25 degrees C (reduced pressures from 0.21 to 0.87). The updated general flow boiling heat transfer model was compared to a new experimental database which contains 1124 data points (790 more than that in the previous model [Cheng et al., 2006, 2007]) in this study. Good agreement between the predicted and experimental data was found in general with 71.4% of the entire database and 83.2% of the database without the dryout and mist flow data predicted within +/-30%. However, the predictions for the dryout and mist flow regions were less satisfactory due to the limited number of data points, the higher inaccuracy in such data, scatter in some data sets ranging up to 40%, significant discrepancies from one experimental study to another and the difficulties associated with predicting the inception and completion of dryout around the perimeter of the horizontal tubes. (C) 2007 Elsevier Ltd. All rights reserved.

New Rapid Derivative Spectrophotometric and Chromatographic Methods for Assay of Loratadine in Tablets and Syrups

New rapid first-derivative spectrophotometric (UVDS) and a stability-indicating high performance liquid chromatographic (HPLC) methods were developed, validated and successfully applied in the analysis of loratadine (LT) in tablets and syrups. In the UVDS method, 0.1 M HCl was used as solvent. The measurements were made at 312.4 nm in the first order derivative spectra. The HPLC method was carried out on a RP-18 column with a mobile phase composed of methanol-water-tetrahydrofuran (50:30:20, v/v/v). UV detection was made at 247 nm. For HPLC methods the total analysis time was <3min, adequate for routine quality control of tablets and syrups containing loratadine.

Effectiveness of a new toothbrush design versus a conventional tongue scraper in improving breath odor and reducing tongue microbiota

For centuries, specific instruments or regular toothbrushes have routinely been used to remove tongue biofilm and improve breath odor. Toothbrushes with a tongue scraper on the back of their head have recently been introduced to the market. The present study compared the effectiveness of a manual toothbrush with this new design, i.e., possessing a tongue scraper, and a commercial tongue scraper in improving breath odor and reducing the aerobic and anaerobic microbiota of tongue surface. The evaluations occurred at 4 moments, when the participants (n=30) had their halitosis quantified with a halimeter and scored according to a 4-point scoring system corresponding to different levels of intensity. Saliva was collected for counts of aerobic and anaerobic microorganisms. Data were analyzed statistically by Friedman's test (p<0.05). When differences were detected, the Wilcoxon test adjusted for Bonferroni correction was used for multiple comparisons (group to group). The results confirmed the importance of mechanical cleaning of the tongue, since this procedure provided an improvement in halitosis and reduction of aerobe and anaerobe counts. Regarding the evaluated methods, the toothbrush's tongue scraper and conventional tongue scraper had a similar performance in terms of breath improvement and reduction of tongue microbiota, and may be indicated as effective methods for tongue cleaning.

Comparative study of intermaxillary relationships of manual and swallowing methods

This study compared the mandibular displacement from three methods of centric relation record using an anterior jig associated with (A) chin point guidance, (B) swallowing (control group) and (C) bimanual manipulation. Ten patients aged 25-39 years were selected if they met the following inclusion criteria: complete dentition (up to the second molars), Angle class I and absence of signs and symptoms of temporomandibular disorders and diagnostic casts showing stability in the maximum intercuspation (MI) position. Impressions of maxillary and mandibular arches were made with an irreversible hydrocolloid impression material. Master casts of each patient were obtained, mounted on a microscope table in MI as a reference position and 5 records of each method were made per patient. The mandibular casts were then repositioned with records interposed and new measurements were obtained. The difference between the two readings allowed measuring the displacement of the mandible in the anteroposterior and lateral axes. Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. There was no statistically significant differences (p>0.05) among the three methods for measuring lateral displacement (A=0.38 ± 0.26, B=0.32 ± 0.25 and C=0.32 ± 0.23). For the anteroposterior displacement (A=2.76 ± 1.43, B=2.46 ± 1.48 and C=2.97 ± 1.51), the swallowing method (B) differed significantly from the others (p<0.05), but no significant difference (p>0.05) was found between chin point guidance (A) and bimanual manipulation (C). In conclusion, the swallowing method produced smaller mandibular posterior displacement than the other methods.

NEW MICROSATELLITE LOCI FOR WATER YAM (DIOSCOREA ALATA, DIOSCOREACEAE) AND CROSS-AMPLIFICATION FOR OTHER DIOSCOREA SPECIES

Premise of the study: Dioscorea alata L. is one of the most widely distributed species of the genus in the humid and semihumid tropics and is associated with traditional agriculture. Only a few microsatellite markers have been developed so far for this and other Dioscorea species. Methods and Results: We isolated 14 codominant polymorphic microsatellite markers using a microsatellite-enriched genomic library technique. Ten microsatellite loci were selected, and 80 D. alata accessions from different regions in Brazil were evaluated with nine polymorphic loci. The polymorphism information content (PIC) varied from 0.39 to 0.78 and the power discrimination (PD) ranged from 0.15 to 0.91. Six of the markers showed transferability for the species D. bulbifera, D. cayenensis-D. rotundata, and D. trifida. Conclusions: The SSR markers obtained are an important tool for further studies aiming to characterize the genetic diversity in D. alata and other Dioscorea spp. accessions.

Plasmodium vivax circumsporozoite genotypes: a limited variation or new subspecies with major biological consequences?

Background: Plasmodium vivax circumsporozoite variants have been identified in several geographical areas. The real implication of the genetic variation in this region of the P. vivax genome has been questioned for a long time. Although previous studies have observed significant association between VK210 and the Duffy blood group, we present here that evidences of this variation are limited to the CSP central portion. Methods: The phylogenetic analyses were accomplished starting from the amplification of conserved domains of 18 SSU RNAr and Cyt B. The antibodies responses against the CSP peptides, MSP-1, AMA-1 and DBP were detected by ELISA, in plasma samples of individuals infected with two P. vivax CS genotypes: VK210 and P. vivax-like. Results: These analyses of the two markers demonstrate high similarity among the P. vivax CS genotypes and surprisingly showed diversity equal to zero between VK210 and P. vivax-like, positioning these CS genotypes in the same clade. A high frequency IgG antibody against the N- and C-terminal regions of the P. vivax CSP was found as compared to the immune response to the R- and V-repetitive regions (p = 0.0005, Fisher's Exact test). This difference was more pronounced when the P. vivax-like variant was present in the infection (p = 0.003, Fisher's Exact test). A high frequency of antibody response against MSP-1 and AMA-1 peptides was observed for all P. vivax CS genotypes in comparison to the same frequency for DBP. Conclusions: This results target that the differences among the P. vivax CS variants are restrict to the central repeated region of the protein, mostly nucleotide variation with important serological consequences.

Polydimethylsiloxane: a new contrast material for localization of occult breast lesions

Background. The radioguided localization of occult breast lesions (ROLL) technique often utilizes iodinated radiographic contrast to assure that the local injection of (99m)Tc-MAA corresponds to the location of the lesion under investigation. However, for this application, this contrast has several shortcomings. The objective of this study was to evaluate the safety, effectiveness and technical feasibility of the use of polydimethylsiloxane (PDMS) as radiological contrast and tissue marker in ROLL. Materials and methods. The safety assessment was performed by the acute toxicity study in Wistar rats (n = 50). The radiological analysis of breast tissue (n = 32) from patients undergoing reductive mammoplasty was used to verify the effectiveness of PDMS as contrast media. The technical feasibility was evaluated through the scintigraphic and histologic analysis. Results. We found no toxic effects of PDMS for this use during the observational period. It has been demonstrated in human breast tissue that the average diameter of the tissue marked by PDMS was lower than when marked by the contrast medium (p <0.001). PDMS did not interfere with the scintigraphic uptake (p = 0.528) and there was no injury in histological processing of samples. Conclusions. This study demonstrated not only the superiority of PDMS as radiological contrast in relation to the iodinated contrast, but also the technical feasibility for the same applicability in the ROLL.