Methodologies for the analysis of pesticides and pharmaceuticals in sediments and plant tissue

Eco-technologies that utilize natural processes involving wetland vegetation, soil and their associated microbial assemblages are increasingly used for the removal of contaminants of emerging concern (CECs) from polluted water. However, information on removal processes in these systems is not always available, possibly due to the lack of simple and robust methodologies for analysis of CECs in complex matrices such as sediment and plant tissue. The aim of the present study was to use a simple and fast procedure based on ultrasonic extraction (USE) and reduced clean-up procedures to analyse 8 pesticides and 9 pharmaceuticals by high-performance liquid chromatography (HPLC) coupled with diode array detector. The established methods demonstrated suitable sensitivity and reliability, and proved fit-for-purpose in quantifying multiple classes of pesticides and pharmaceuticals. For sediments, extraction with methanol/acetone (95:5, v/v) followed by a simple evaporation to dryness and redissolution (water:methanol 50:50) provided acceptable recovery (50 - 101%) and RSD 64%) with RSD < 22% determined using different types of wetland plants. The methodology has been successfully applied in different studies on the fate of emerging contaminants in water treatment eco-technology systems

Simulation study of the inhomogeneous Olami-Feder-Christensen model of earthquakes

Statistical properties of the inhomogeneous version of the Olami-Feder-Christensen (OFC) model of earthquakes is investigated by numerical simulations. The spatial inhomogeneity is assumed to be dynamical. Critical features found in the original homogeneous OFC model, e.g., the Gutenberg-Richter law and the Omori law are often weakened or suppressed in the presence of inhomogeneity, whereas the characteristic features found in the original homogeneous OFC model, e.g., the near-periodic recurrence of large events and the asperity-like phenomena persist.Comment: Shortened from the first version. To appear in European Physical Journal

Agrobacterium-mediated transformation of sorghum: factors that affect transformation efficiency.

The results presented in this work support the hypothesis that Agrobacterium-mediated transformation of sorghum is feasible, analogous to what has been demonstrated for other cereals such as rice, maize, barley and wheat. The four factors that we found most influenced transformation were: the sensitivity of immature sorghum embryos to Agrobacterium infection, the growth conditions of the donor plant, type of explant and co-cultivation medium. A major problem during the development of our protocol was a necrotic response which developed in explants after co-cultivation. Immature sorghum embryos proved to be very sensitive to Agrobacterium infection and we found that the level of embryo death after co-cultivation was the limiting step in improving transformation efficiency. The addition of coconut water to the co-cultivation medium, the use of vigorous and actively growing immature embryos and the removal of excess bacteria significantly improved the survival rate of sorghum embryos and was critical for successful transformation. Hygromycin phosphotransferase (hpt) proved to be a good selectable marker for sorghum. We also found that &#946;-glucuronidase (GUS) activity was low in most of the transgenic plant tissues tested, although it was very high in immature inflorescences. Although promising, the overall transformation efficiency of the protocol is still low and further optimization will require particular attention to be given to the number of Agrobacterium in the inoculum and the selection of sorghum genotypes and explants less sensitive to Agrobacterium infection

Correlations around an interface

We compute one-loop correlation functions for the fluctuations of an interface using a field theory model. We obtain them from Feynman diagrams drawn with a propagator which is the inverse of the Hamiltonian of a Poschl-Teller problem. We derive an expression for the propagator in terms of elementary functions, show that it corresponds to the usual spectral sum, and use it to calculate quantities such as the surface tension and interface profile in two and three spatial dimensions. The three-dimensional quantities are rederived in a simple, unified manner, whereas those in two dimensions extend the existing literature, and are applicable to thin films. In addition, we compute the one-loop self-energy, which may be extracted from experiment, or from Monte Carlo simulations. Our results may be applied in various scenarios, which include fluctuations around topological defects in cosmology, supersymmetric domain walls, Z(N) bubbles in QCD, domain walls in magnetic systems, interfaces separating Bose-Einstein condensates, and interfaces in binary liquid mixtures.Comment: RevTeX, 13 pages, 6 figure

Elaboração e caracterização físico-química e sensorial de estruturados de polpa concentrada de abacaxi.

Este trabalho teve por objetivo estudar o procedimento de estruturação de polpa concentrada de abacaxi, empregando-se diferentes hidrocoloides e altas concentrações de polpa de abacaxi. Os hidrocoloides utilizados foram: pectina de baixa metoxilação, gelatina, ágar-ágar e alginato de sódio. Utilizou-se como processo para concentração da polpa a desidratação osmótica e a concentração por evaporação á vácuo. O fruto in natura foi submetido a análises físico-químicas e para os estruturados foram realizadas análises físico-químicas e sensoriais. Os resultados mostraram ser possível obter estruturados a partir de polpa concentrada de abacaxi, com concentrações significativas de vitamina C, proteína e fibra. Quanto à análise sensorial, os estruturados de abacaxi obtiveram elevada aceitação por parte dos possíveis compradores, apresentando índices elevados de intenção de compra, com cerca de 90% dos provadores que afirmaram que certamente ou possivelmente comprariam o produto se o encontrassem à venda

Elaboração e caracterização de estruturado obtido de polpa concentrada de cupuaçu.

O objetivo deste trabalho foi elaborar um estruturado a partir de polpa concentrada de cupuaçu, avaliando-se o efeito da combinação de gelatina e pectina de baixa metoxilação nas características do gel da fruta.Realizou-se, na polpa de cupuaçu e nos estruturados obtidos, análises de composição centesimal, atividade de água, pH, acidez titulável, sólidos solúveis (Brix°), açúcares totais e redutores e teor de vitamina C,além da análise sensorial dos produtos finais. Os resultados mostram que é possível estabelecer um procedimento tecnológico para a produção de fruta estruturada com alto teor de polpa, variando entre 78,24 a 81,43%.Optou-se pela formulação 3, como aquela de possível aplicação em escala industrial, pois foi a que apresentou melhor aceitação sensorial. De maneira geral, todas as formulações apresentaram-se como um produto finalde textura firme, sem pegajosidade e saudável, tendo em vista seus teores de vitamina C (240,9 a 247,3 mg kg-1) e fibras (3,23 a 3,90%), considerados significativos do ponto de vista nutricional

Cultivo de meristemas apicais de plantas in vitro para limpeza viral em abacaxi.

O abacaxi é uma das frutas tropicais mais apreciadas em todo mundo. O Brasil, como um dos centros de origem e diversidade genética da espécie, tem se destacado no melhoramento genético e na conservação de germoplasma desta importante fruteira (Cabral et al.,2004). Dentre as doenças de maior impacto na abacaxicultura brasileira destaca-se a fusariose, para a qual várias ações estão sendo desenvolvidas, incluindo o lançamento de híbridos resistentes. O programa de melhoramento da Embrapa Mandioca e Fruticultura Tropical (CNPMF) já lançou os abacaxis Imperial, Vitória e Ajubá, com excelentes características organolépticas, alta produtividade e resistentes à fusariose (Cabral e Matos, 2005; Ventura et al., 2007; Cabral e Matos, 2008).pdf 70