Structure, spatial distribution and seed yield for andiroba ( Carapa guianensis Aubl.) in south Roraima

A andiroba, \ue9 uma das esp\ue9cies arb\uf3reas amaz\uf4nicas com grande potencial de explora\ue7\ue3o madeireira e n\ue3o madeireira, sendo este trabalho desenvolvido com o objetivo de estudar a estrutura populacional, a distribui\ue7\ue3o espacial e a produ\ue7\ue3o de sementes em uma popula\ue7\ue3o nativa de andiroba localizada no sul do estado de Roraima. Para a realiza\ue7\ue3o deste estudo foi instalada uma parcela permanente de 300 x 300 m (9 ha) onde todos os indiv\uedduos com DAP (di\ue2metro tomado a 1,30 m do solo) igual ou superior a 10 cm, foram identificados, mapeados e medidos. Em cada \ue1rvore, foram avaliadas a exposi\ue7\ue3o da copa a luz, a forma da copa e a presen\ue7a de cip\uf3s. Para identificar o padr\ue3o de distribui\ue7\ue3o espacial utilizaram-se a raz\ue3o vari\ue2ncia m\ue9dia e o \ucdndice de Morisita. Os dados de produ\ue7\ue3o foram obtidos pela pesagem das sementes, sendo monitoradas 145 \ue1rvores durante o ano de 2006. Observou-se que a popula\ue7\ue3o estudada apresentou uma distribui\ue7\ue3o diam\ue9trica do tipo J Invertido, com uma produ\ue7\ue3o de sementes de 65,4 kg.ha-1, com m\ue9dia de 8,3 kg.\ue1rvore-1. O di\ue2metro de 30 cm foi considerado como lim\uedtrofe para a produ\ue7\ue3o comercial de sementes, permitindo estratificar a popula\ue7\ue3o em jovens (DAP 64 30 cm) e adultos (DAP> 30 cm). O padr\ue3o de distribui\ue7\ue3o espacial foi agregado para toda a popula\ue7\ue3o, por\ue9m, os indiv\uedduos jovens apresentaram padr\ue3o agregado e os adultos distribui\ue7\ue3o regular.Andiroba is one of the Amazon species with great potential of exploration for timber and non-timber forest products (NFTPs). This work was carried out with the objective of studying the population structure, spatial distribution and seed yield in a native forest of andiroba in the south of Roraima state. A permanent sample plot of 300 x 300 m (9 ha) was installed and all the trees with DBH equal or superior to 10 cm were identified, mapped and measured. In each tree, the light climate, crown form and lianas load were appraised. To identify the spatial distribution, the medium variance/average rate and the Morisita\u2019s Index were used. The seed yield data were obtained by the seed weighing, being 145 trees monitored during 2006. The population presented a diametric distribution of the j inverted type, and a seed yield of 65,4 kg.ha-1 with average of 8,3 kg.tree-1 was observed. DBH 65 30 cm was considered as borderline for commercial seed yield, allowing stratifying the population in juveniles (DBH 64 30 cm) and adults (DBH > 30 cm). The spatial distribution analysis showed that adult individuals presented random distribution and the juveniles tendency of grouping

A Surrogate Based Multi-fidelity Approach for Robust Design Optimization

Robust design optimization (RDO) is a field of optimization in which certain measure of robustness is sought against uncertainty. Unlike conventional optimization, the number of function evaluations in RDO is significantly more which often renders it time consuming and computationally cumbersome. This paper presents two new methods for solving the RDO problems. The proposed methods couple differential evolution algorithm (DEA) with polynomial correlated function expansion (PCFE). While DEA is utilized for solving the optimization problem, PCFE is utilized for calculating the statistical moments. Three examples have been presented to illustrate the performance of the proposed approaches. Results obtained indicate that the proposed approaches provide accurate and computationally efficient estimates of the RDO problems. Moreover, the proposed approaches outperforms popular RDO techniques such as tensor product quadrature, Taylor’s series and Kriging. Finally, the proposed approaches have been utilized for robust hydroelectric flow optimization, demonstrating its capability in solving large scale problems

Changing trends in mastitis

<p>Abstract</p> <p>The global dairy industry, the predominant pathogens causing mastitis, our understanding of mastitis pathogens and the host response to intramammary infection are changing rapidly. This paper aims to discuss changes in each of these aspects. Globalisation, energy demands, human population growth and climate change all affect the dairy industry. In many western countries, control programs for contagious mastitis have been in place for decades, resulting in a decrease in occurrence of <it>Streptococcus agalactiae </it>and <it>Staphylococcus aureus </it>mastitis and an increase in the relative impact of <it>Streptococcus uberis </it>and <it>Escherichia coli </it>mastitis. In some countries, <it>Klebsiella </it>spp. or <it>Streptococcus dysgalactiae </it>are appearing as important causes of mastitis. Differences between countries in legislation, veterinary and laboratory services and farmers' management practices affect the distribution and impact of mastitis pathogens. For pathogens that have traditionally been categorised as contagious, strain adaptation to human and bovine hosts has been recognised. For pathogens that are often categorised as environmental, strains causing transient and chronic infections are distinguished. The genetic basis underlying host adaptation and mechanisms of infection is being unravelled. Genomic information on pathogens and their hosts and improved knowledge of the host's innate and acquired immune responses to intramammary infections provide opportunities to expand our understanding of bovine mastitis. These developments will undoubtedly contribute to novel approaches to mastitis diagnostics and control.</p

Characteristics of volatile organic compounds emission profiles from hot road bitumens

A procedure for the investigation and comparison of volatile organic compounds (VOCs) emission profiles to the atmosphere from road bitumens with various degrees of oxidation is proposed. The procedure makes use of headspace analysis and gas chromatography with universal as well as selective detection, including gas chromatography–mass spectrometry (GC–MS). The studies revealed that so-called vacuum residue, which is the main component of the charge, contains variable VOC concentrations, from trace to relatively high ones, depending on the extent of thermal cracking in the boiler of the vacuum distillation column. The VOC content in the oxidation product, so-called oxidized paving bitumen, is similarly varied. There are major differences in VOC emission profiles between vacuum residue and oxidized bitumens undergoing thermal cracking. The VOC content in oxidized bitumens, which did not undergo thermal cracking, increases with the degree of oxidation of bitumens. The studies revealed that the total VOC content increases from about 120ppm for the raw vacuum residue to about 1900ppm for so-called bitumen 35/50. The amount of volatile sulfur compounds (VSCs) in the volatile fraction of fumes of oxidized bitumens increases with the degree of oxidation of bitumen and constitutes from 0.34% to 3.66% (w/w). The contribution of volatile nitrogen compounds (VNCs) to total VOC content remains constant for the investigated types of bitumens (from 0.16 to 0.28% (w/w) of total VOCs). The results of these studies can also find use during the selection of appropriate bitumen additives to minimize their malodorousness. The obtained data append the existing knowledge on VOC emission from oxidized bitumens. They should be included in reports on the environmental impact of facilities in which hot bitumen binders are used

Process Control and Investigation of Oxidation Kinetics of Postoxidative Effluents Using Gas Chromatography with Pulsed Flame Photometric Detection (GC-PFPD)

This article presents the results of investigations on the use of headspace analysis and gas chromatography with pulsed flame photometric detection (HSA-GC-PFPD) to evaluate the effectiveness of oxidation of postoxidative effluents from the production of bitumens. Samples of effluents from the bitumen oxidation unit were used in the experiments. In addition, the kinetics of effluent oxidation was also investigated. The content of volatile sulfur compounds (VSCs) was determined using HSA-GC-PFPD. The results were correlated with chemical oxygen demand (COD). The changes in concentration of individual volatile sulfur compounds in the course of effluent oxidation were measured, which enabled the determination of the order of the oxidation reactions. The usefulness of the determination of VSCs in the headspace as a reliable technique for evaluating the reduction in emissions of volatile malodorous compounds was demonstrated. The developed method is also useful for process control of the oxidation of postoxidative effluents. The procedure ensures an objective evaluation of the effectiveness of the removal of volatile sulfur compounds from postoxidative effluents. The experimental results revealed that the effectiveness of the oxidation of organosulfur compounds was much higher than that of other classes of organic compounds. Furthermore, the order of oxidation reactions along with the rate constants of thiophenol, p-thiocresol, and hydrogen sulfide were determined. An advantage of the developed procedure is that it can be automated

New Procedures for Control of Industrial Effluents Treatment Processes

This work presents the procedures for monitoring volatile organic compounds during treatment of industrial effluents. The investigation was carried out for a specific effluent—caustic effluent from bitumen production. The developed procedures enable more detailed control of the effectiveness of wastewater treatment than standard procedures. Caustic effluents from bitumen production have a complex physicochemical form and consist of an emulsion of an organic phase in a strongly alkaline aqueous phase. The occurrence of an emulsified organic phase in the aqueous phase of the effluents results in their high toxicity toward the activated sludge of a refinery wastewater treatment plant as well as strong malodorousness. Interpretation of analytical results reveals that the effluents contain over 400 organic compounds among volatile organic compounds (VOCs) alone. Using the developed procedures, 114 of the VOCs were identified in raw postoxidative effluents. The procedures described in this work allow detailed identification of VOCs as well as the determination of distribution of their concentrations for individual classes of chemical compounds. Monitoring changes in content of individual classes of VOCs, including highly malodorous volatile sulfur compounds, as well as changes in total VOC content, provides more information on the processes taking place during wastewater treatment

A new procedure for the determination of distillation temperature distribution of high-boiling petroleum products and fractions

The distribution of distillation temperatures of liquid and semi-fluid products, including petroleum fractions and products, is an important process and practical parameter. It provides information on properties of crude oil and content of particular fractions, classified on the basis of their boiling points, as well as the optimum conditions of atmospheric or vacuum distillation. At present, the distribution of distillation temperatures is often investigated by simulated distillation (SIMDIS) using capillary gas chromatography (CGC) with a short capillary column with polydimethylsiloxane as the stationary phase. This paper presents the results of investigations on the possibility of replacing currently used CGC columns for SIMDIS with a deactivated fused silica capillary tube without any stationary phase. The SIMDIS technique making use of such an empty fused silica column allows a considerable lowering of elution temperature of the analytes, which results in a decrease of the final oven temperature while ensuring a complete separation of the mixture. This eliminates the possibility of decomposition of less thermally stable mixture components and bleeding of the stationary phase which would result in an increase of the detector signal. It also improves the stability of the baseline, which is especially important in the determination of the end point of elution, which is the basis for finding the final temperature of distillation. This is the key parameter for the safety process of hydrocracking, where an excessively high final temperature of distillation of a batch can result in serious damage to an expensive catalyst bed. This paper compares the distribution of distillation temperatures of the fraction from vacuum distillation of petroleum obtained using SIMDIS with that obtained by the proposed procedure. A good agreement between the two procedures was observed. In addition, typical values of elution temperatures of n-paraffin standards obtained by the two procedures were compared. Finally, the agreement between boiling points of polar compounds determined from their retention times and actual boiling points was investigated. Figure SIMDIS and EC-GC distillation curves of fractions B, C, and

ESTRUTURA, DISTRIBUIÇÃO ESPACIAL E PRODUÇÃO DE SEMENTES DE ANDIROBA (Carapa guianensis Aubl.) NO SUL DO ESTADO DE RORAIMA

Andiroba is one of the Amazon species with great potential of exploration for timber and non-timber forest products (NFTPs). This work was carried out with the objective of studying the population structure, spatial distribution and seed yield in a native forest of andiroba in the south of Roraima state. A permanent sample plot of 300 x 300 m (9 ha) was installed and all the trees with DBH equal or superior to 10 cm were identified, mapped and measured. In each tree, the light climate, crown form and lianas load were appraised. To identify the spatial distribution, the medium variance/average rate and the Morisita¿s Index were used. The seed yield data were obtained by the seed weighing, being 145 trees monitored during 2006. The population presented a diametric distribution of the j inverted type, and a seed yield of 65,4 kg.ha-1 with average of 8,3 kg.tree-1 was observed. DBH > 30 cm was considered as borderline for commercial seed yield, allowing stratifying the population in juveniles (DBH > 30 cm) and adults (DBH > 30 cm). The spatial distribution analysis showed that adult individuals presented random distribution and the juveniles tendency of grouping

Size-exclusion chromatography for the determination of the boiling point distribution of high-boiling petroleum fractions

The paper describes a new procedure for the determination of boiling point distribution of high-boiling petroleum fractions using size-exclusion chromatography with refractive index detection. Thus far, the determination of boiling range distribution by chromatography has been accomplished using simulated distillation with gas chromatography with flame ionization detection. This study revealed that in spite of substantial differences in the separation mechanism and the detection mode, the size-exclusion chromatography technique yields similar results for the determination of boiling point distribution compared with simulated distillation and novel empty column gas chromatography. The developed procedure using size-exclusion chromatography has a substantial applicability, especially in case of determination of exact final boiling point values for high-boiling mixtures, for which a standard high-temperature simulated distillation would have to be used. In this case, the precision of final boiling point determination is low due to the high final temperatures of the gas chromatograph oven and an insufficient thermal stability of both the gas chromatography stationary phase and the sample. Additionally, the use of high-performance liquid chromatography detectors more sensitive than refractive index detection allows a lower detection limit for high-molar-mass aromatic compounds, and thus increases the sensitivity of final boiling point determination.This article is protected by copyright. All rights reserve