RAPID AND SENSITIVE DETERMINATION OF PALLADIUM USING HOMOGENEOUS LIQUID-LIQUID MICROEXTRACTION VIA FLOTATION ASSISTANCE FOLLOWED BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROMETRY

A method for the determination of trace amounts of palladium was developed using homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA) followed by graphite furnace atomic absorption spectrometry (GFAAS). Ammonium pyrrolidine dithiocarbamate (APDC) was used as a complexing agent. This was applied to determine palladium in three types of water samples. In this study, a special extraction cell was designed to facilitate collection of the low-density solvent extraction. No centrifugation was required in this procedure. The water sample solution was added to the extraction cell which contained an appropriate mixture of extraction and homogeneous solvents. By using air flotation, the organic solvent was collected at the conical part of the designed cell. Parameters affecting extraction efficiency were investigated and optimized. Under the optimum conditions, the calibration graph was linear in the range of 1.0-200 µg L-1 with a limit of detection of 0.3 µg L-1. The performance of the method was evaluated for the extraction and determination of palladium in water samples and satisfactory results were obtained. In order to verify the accuracy of the approach, the standard addition method was applied for the determination of palladium in spiked synthetic samples and satisfactory results were obtained.

Identification of rapd marker linked to blast resistance gene in a somaclone of rice cultivar Araguaia

The gene Pi-ar confers resistance to Pyricularia grisea race IB-45 in a somaclone derived from immature panicles of the susceptible rice (Oryza sativa) cultivar Araguaia. RAPD technique was used to identify molecular markers linked to this gene utilizing bulked segregant analysis. Initially, the two parental DNAs from the resistant donor SC09 and 'Araguaia' were analyzed using random primers. Of the 240 primers tested, 203 produced amplification products. The two parental DNAs along with the resistant and susceptible bulks of F2 population were screened using 48 primers that differentiated resistant and susceptible parents. Even though eight primers differentiated the resistant bulk from the susceptible bulk, as well as somaclone SC09 and 'Araguaia', only one primer, OPC02 ('GTGAGGCGTC'), was found to be tightly linked (1.7cM) to the resistance gene of somaclone SC09.

Soluble tissue sugar content and leaf blast severity in response to the application of calcinated serpentinite as a silicon source in irrigated rice

A field experiment conducted with the irrigated rice cultivar BRS Formoso, to assess the efficiency of calcinated serpentinite as a silicon source on grain yield was utilized to study its effect on leaf blast severity and tissue sugar levels. The treatments consisted of five rates of calcinated serpentinite (0, 2, 4, 6, 8 Mg.ha-1) incorporated into the soil prior to planting. The leaf blast severity was reduced at the rate of 2.96% per ton of calcinated serpentinite. The total tissue sugar content decreased significantly as the rates of serpentinite applied increased (R² = 0.83). The relationship between the tissue sugar content and leaf blast severity was linear and positive (R² = 0.81). The decrease in leaf blast severity with increased rates of calcinated serpentinite was also linear (R²= 0.96) and can be ascribed to reduced sugar level.

Development of a warning system for wheat blast caused by Pyricularia grisea

Wheat (Triticum aestivum L.) blast caused by Pyricularia grisea is a new disease in Brazil and no resistant cultivars are available. The interactions between temperature and wetness durations have been used in many early warning systems. Hence, growth chamber experiments to assess the effect of different temperatures (10, 15, 20, 25, 30 and 35ºC) and the duration of spike-wetness (0, 5, 10, 15, 20, 25, 30, 35 and 40 hours) on the intensity of blast in cultivar BR23 were carried out. Each temperature formed an experiment and the duration of wetness the treatments. The highest blast intensity was observed at 30°C and increased as the duration of the wetting period increased while the lowest occurred at 25°C and 10 hours of spike wetness. Regardless of the temperature, no symptoms occurred when the wetting period was less than 10 hours but at 25°C and a 40 h wetting period blast intensity exceeded 85%. These variations in blast intensity as a function of temperature are explained by a generalized beta model and as a function of the duration of spike wetness by the Gompertz model. Disease intensity was modeled as a function of both temperature and the durations of spike wetness and the resulting equation provided a precise description of the response of P. grisea to temperatures and the durations of spike wetness. This model was used to construct tables that can be used to predict the intensity of P. grisea wheat blast based on the temperatures and the durations of wheat spike wetness obtained in the field.

Diagrammatic scale for the assessment of blast on wheat spikes

The correct quantification of blast caused by the fungus Magnaporthe oryzae on wheat (Triticum aestivum) spikes is an important component to understand the development of this disease aimed at its control. Visual quantification based on a diagrammatic scale can be a practical and efficient strategy that has already proven to be useful against several plant pathosystems, including diseases affecting wheat spikes like glume blotch and fusarium head blight. Spikes showing different disease severity values were collected from a wheat field with the aim of elaborating a diagrammatic scale to quantify blast severity on wheat spikes. The spikes were photographed and blast severity was determined by using resources of the software ImageJ. A diagrammatic scale was developed with the following disease severity values: 3.7, 7.5, 21.4, 30.5, 43.8, 57.3, 68.1, 86.0, and 100.0%. An asymptomatic spike was added to the scale. Scale validation was performed by eight people who estimated blast severity by using digitalized images of 40 wheat spikes. The precision and the accuracy of the evaluations varied according to the rater (0.82blast on wheat spikes.

Jätteenpolton typenoksidipäästöjen vähentäminen

Työn tavoitteena oli selvittää jätteenpolton typenoksidipäästöjen puhdistusmahdollisuuksia. Työssä käydään läpi typen oksidien muodostuminen poltossa ja typen oksidien poistomenetelmät. Poistomenetelmiä käsiteltäessä painotus on arinapoltossa ja erityisesti selektiivisessä ei-katalyyttimenetelmässä (SNCR). Työn kokeellinen osa tehtiin Ekokem Oy Ab:n jätevoimalassa Riihimäellä. Kokeellisessa osassa selvitettiin ensin ammoniakkiveden massavirran, SNCR-laitteiston veden massavirran ja räjähdysnuohouksen vaikutusta typenoksidipitoisuuteen. Samalla selvitettiin muita typenoksidipitoisuuteen vaikuttavia tekijöitä sekä SNCR-laitteiston puhdistustehokkuus. Sen jälkeen selvitettiin parhaita toiminta-arvoja öljyisen veden massavirralle, SNCR-laitteiston massavirralle ja primääri- ja sekundääri-ilman suhteelle typenoksidipitoisuuden, ammoniakki-slip:n, ilokaasupitoisuuden, ammoniakkiveden kulutuksen ja höyryn tuotannon kannalta. Tulokseksi saatiin, että ammoniakkiveden massavirran lisääminen pienentää typenoksidipitoisuutta, mutta voi aiheuttaa ammoniakkipäästön. Paras SNCR-laitteiston veden massavirta on suurin tutkittu, 800 kg/h, jolloin typenoksidipitoisuus sekä typenoksidipitoisuuden hetkittäinen vaihtelu, ammoniakkiveden kulutus ja ammoniakkipäästö ovat pienimmät. Samalla tosin höyryn virtaama pienenee. SNCR-laitteiston puhdistustehokkuudeksi saatiin 60 %. Räjähdysnuohouksella ei ole havaittavaa, eikä öljyisen veden massavirralla merkittävää vaikutusta typenoksidipitoisuuteen. Ammoniakkiveden kulutuksen kannalta paras öljyisen veden määrä on 600 kg/h, kun taas ammoniakki-slip:n kannalta paras öljyisen veden määrä on 950 kg/h. Primääri-ilman osuuden pienentäminen pienentää ammoniakki-slip:iä ja ammoniakkiveden kulutusta.

Modelling of combustion and sorbent reactions in three-dimensional flow environment of a circulating fluidized bed furnace

This thesis presents a three-dimensional, semi-empirical, steady state model for simulating the combustion, gasification, and formation of emissions in circulating fluidized bed (CFB) processes. In a large-scale CFB furnace, the local feeding of fuel, air, and other input materials, as well as the limited mixing rate of different reactants produce inhomogeneous process conditions. To simulate the real conditions, the furnace should be modelled three-dimensionally or the three-dimensional effects should be taken into account. The only available methods for simulating the large CFB furnaces three-dimensionally are semi-empirical models, which apply a relatively coarse calculation mesh and a combination of fundamental conservation equations, theoretical models and empirical correlations. The number of such models is extremely small. The main objective of this work was to achieve a model which can be applied to calculating industrial scale CFB boilers and which can simulate all the essential sub-phenomena: fluid dynamics, reactions, the attrition of particles, and heat transfer. The core of the work was to develop the model frame and the required sub-models for determining the combustion and sorbent reactions. The objective was reached, and the developed model was successfully used for studying various industrial scale CFB boilers combusting different types of fuel. The model for sorbent reactions, which includes the main reactions for calcitic limestones, was applied for studying the new possible phenomena occurring in the oxygen-fired combustion. The presented combustion and sorbent models and principles can be utilized in other model approaches as well, including other empirical and semi-empirical model approaches, and CFD based simulations. The main achievement is the overall model frame which can be utilized for the further development and testing of new sub-models and theories, and for concentrating the knowledge gathered from the experimental work carried out at bench scale, pilot scale and industrial scale apparatus, and from the computational work performed by other modelling methods.

Altos custos financeiros do trauma vascular

OBJETIVO: Demonstrar o custo e impacto financeiro referente à primeira abordagem cirúrgica das lesões vasculares em pacientes admitidos no Hospital João XXIII/FHEMIG, entre os anos de 2004 a 2006. MéTODOS: Trata-se de um estudo com aprovação ética, retrospectivo, de coorte e descritivo realizado a partir da auditoria de contas hospitalares referentes a 70 prontuários catalogados pelo Serviço de Trauma Cardiovascular. RESULTADOS: Cinco (7,14%) prontuários foram excluídos por má qualidade técnica. O valor monetário repassado pelo Sistema Único de Saúde e pelo setor privado foram de R$ 103.614,96 (US$ 60.949,97) e de R$ 185.888,21 (US$ 109.346,0, respectivamente, implicando em defasagem potencial de 44%. Houve correlação direta entre custos e topografia anatômica das lesões e exponencial em relação às variáveis hemoderivados e próteses vasculares. CONCLUSÃO: Este estudo corrobora os altos custos do trauma vascular e fortalece a importância da auditoria de contas para as tomadas de decisões médicas.

Modeling of temperature regimes in a furnace of bubbling fluidized bed boiler

The work is mainly focused on the technology of bubbling fluidized bed combustion. Heat transfer and hydrodynamics of the process were examined in the work in detail. Special emphasis was placed on the process of heat exchange in a freeboard zone of bubbling fluidized bed boiler. Operating mode of bubbling fluidized bed boiler depends on many parameters. To assess the influence of some parameters on a temperature regime inside the furnace a simplified method of zonal modeling was used in the work. Thus, effects of bed material fineness, excess air ratio and changes in boiler load were studied. Besides the technology of combustion in bubbling fluidized bed, other common technologies of solid fuels combustion were reviewed. In addition, brief survey of most widely used types of solid fuel was performed in the work.

Inheritance of blast resistance in rice to two Pyricularia grisea races, IB-1 and IB-9

Seven sources of resistance to the two predominant races IB-1 and IB-9 of the rice blast pathogen Pyricularia grisea were selected based on leaf blast reaction in tests conducted under controlled greenhouse conditions. Crosses involving resistant and susceptible parents were made to study the inheritance of the disease reaction for different sources of resistance. The F1 and F2 progenies of all crosses, including backcrosses to resistant and susceptible parents, were tested for reaction to leaf blast. The data showed that resistance is controlled by one to three genes that segregate independently in most of the donors. Non-allelic interaction among resistance genes, including dominant epistasis, was identified.

In vitro cytotoxicity of the LDE: daunorubicin complex in acute myelogenous leukemia blast cells

Acute myelogenous leukemia (AML) blast cells show high-affinity degradation of low-density lipoprotein (LDL), suggesting an increased expression of cellular LDL receptors. LDE is a lipid microemulsion easily synthesized in vitro which is known to mimic the metabolic pathway of LDL. We used LDE as a carrier for daunorubicin and assayed the cytotoxicity of the complex using AML blast cells since RT-PCR analysis showed that AML cells express LDL receptor mRNA. The LDE:daunorubicin complex killed 46.7% of blast cells and 20.2% of normal bone marrow cells (P<0.001; Student t-test). Moreover, this complex destroyed AML blast cells as efficiently as free daunorubicin. Thus, LDE might be a suitable carrier of chemotherapeutic agents targeting these drugs to neoplastic cells and protecting normal tissues.

pp-Blast: a "pseudo-parallel" Blast

We have developed a software called pp-Blast that uses the publicly available Blast package and PVM (parallel virtual machine) to partition a multi-sequence query across a set of nodes with replicated or shared databases. Benchmark tests show that pp-Blast running in a cluster of 14 PCs outperformed conventional Blast running in large servers. In addition, using pp-Blast and the cluster we were able to map all human cDNAs onto the draft of the human genome in less than 6 days. We propose here that the cost/benefit ratio of pp-Blast makes it appropriate for large-scale sequence analysis. The source code and configuration files for pp-Blast are available at http://www.ludwig.org.br/biocomp/tools/pp-blast.

Three-dimensional modeling of biomass fuel flow in a circulating fluidized bed furnace

The reduction of greenhouse gas emissions in the European Union promotes the combustion of biomass rather than fossil fuels in energy production. Circulating fluidized bed (CFB) combustion offers a simple, flexible and efficient way to utilize untreated biomass in a large scale. CFB furnaces are modeled in order to understand their operation better and to help in the design of new furnaces. Therefore, physically accurate models are needed to describe the heavily coupled multiphase flow, reactions and heat transfer inside the furnace. This thesis presents a new model for the fuel flow inside the CFB furnace, which acknowledges the physical properties of the fuel and the multiphase flow phenomena inside the furnace. This model is applied with special interest in the firing of untreated biomass. An experimental method is utilized to characterize gas-fuel drag force relations. This characteristic drag force approach is developed into a gas-fuel drag force model suitable for irregular, non-spherical biomass particles and applied together with the new fuel flow model in the modeling of a large-scale CFB furnace. The model results are physically valid and achieve very good correspondence with the measurement results from large-scale CFB furnace firing biomass. With the methods and models presented in this work, the fuel flow field inside a circulating fluidized bed furnace can be modeled with better accuracy and more efficiently than in previous studies with a three-dimensional holistic model frame.