A simple, rapid, sensitive and environmentally friendly separation and preconcentration procedure, based on the carrier element free coprecipitation (CEFC) of Cu(II) and Cd(II) ions by using an organic coprecipitant, 2-{[4-(4-fluorophenyl)-5-sulphanyl-4H-1,2,4-triazol-3-yl]methyl}-4-{[(4-fluorophenyl) methylene]amino}-5-(4-methylphenyl)-2,4-dihydro-3H-1,2,4-triazol-3-one (MEFMAT) was developed. The analyte ions were determined by flame atomic absorption spectrometric (FAAS) determinations. The optimum conditions for the coprecipitation process were investigated on several commonly tested experimental parameters such as pH of the solution, amount of MEFMAT, sample volume, standing time, centrifugation rate and time. The influences of some anions, cations and transition metals on the recoveries of analyte ions were also investigated, and no considerable interference was observed. The preconcentration factor was found to be 50. The detection limits for Cu(II) and Cd(II) ions based on the three times the standard deviation of the blanks (N:10) were found to be 1.49 and 0.45μgL⁻¹, respectively. The relative standard deviations were found to be lower than 3.5% for both analyte ions. The method was validated by analyzing two certified reference materials (CRM-TMDW-500 Drinking Water and CRM-SA-C Sandy Soil C) and spike tests. The procedure was successfully applied to sea water and stream water as liquid samples and tobacco, hazelnut and black tea as solid samples.

In this work, a new method based on dispersive liquid–liquid microextraction (DLLME) preconcentration using tetrachloromethane (CCl₄) as extraction solvent was proposed for the spectrophotometric determination of cadmium and copper in water and food samples. The influence factors relevant to DLLME, such as type and volume of extractant and disperser solvent, concentration of chelating reagents, pH, salt effect, were optimized. Under the optimal conditions, the limits of detection for cadmium and copper were 0.01ng/L and 0.5μg/L, with enhancement factors (EFs) of 3458 and 10, respectively. The tremendous contrast of EFs could come from the different maximum absorption wavelength caused by the different extraction acidity compared with some conventional works and the enhancement effect of acetone used as dilution solvent during the spectrophotometric determination. The proposed method was applied to the determination of water and food samples with satisfactory analytical results. The proposed method was simple, rapid, cost-efficient and sensitive, especially for the detection of cadmium.

A study was carried out to assess the culture performance of monosex and mixed-sex tilapia (Oreochromis niloticus) in underground brackish water by using semi-intensive integrated pond system. The experiment was conducted in three earthen ponds for a period of 11 months. In pond-1 (P1), 200 females and in pond-2 (P2), 200 males, while in pond-3 (P3), 100 male and 100 female tilapias were stocked. Salt-tolerant fresh biomass, i.e. Leptochloa fusca (Kallar grass), Brachiaria mutica (Para grass) and Kochia indica (Kochia) was used as supplemental feed. Fertilization of all ponds was done with goat droppings @ 6000 kg per ha and nitrophos @ 7.5 kg per ha. Results indicated that tilapia was found well adapted to the saline environment. The net fish production was calculated as 1295, 1752 and 914 kg per ha per year in female, male and mixed tilapia ponds, respectively. Male tilapia culture resulted in a significant (P less than 0.05) increase in fish production.

The knowledge and principles generated by CPWF-PN15 confirm that QSMAS can be a model production system for implementing conservation agriculture to achieve food security and sustainable development in drought-prone areas of hillsides in the sub-humid tropics, while providing ecosystem services in the face of land degradation and climate change. As an adoptable option to replace the slash and burn traditional system, QSMAS can improve smallholder livelihoods through eco-efficient use and conservation of natural resources. Participatory validation activities suggest that the conservation agriculture principles embedded in QSMAS can be readily accepted by resource- poor farmers and local authorities in similar agroecosystems | A. Castro et al., 'Quesungual slash and mulch agroforestry system (QSMAS): Improving crop water productivity, food security and resource quality in the sub-humid tropics', CGIAR Challenge Program on Water and Food, 2011

Vibrio is a genus of bacteria present in surface and coastal waters as well as in marine organisms worldwide. In many countries, pathogenic Vibrio species are a main cause of bacterial diarrhea, which may result from comsumption of contaminated seafood and fish products or from drinking contaminated water. Vibrio infections may also gain in importance in our regions due to global warming and the increase in the world trade of seafood. The research network "VibrioNet" studies pathogenic Vibrios in the marine environment and in seafood consumed by humans as a potential, new emerging zoonotic agent. An assessment of the risk arising from pathogenic non-cholera-vibrios in central Europe is the target of a multidisciplinary research effort. The research network will be strengthened by cooperations with international partners from countries in which Vibrio infections play a major role (Bangladesh, Chile, India, Thailand, and Vietnam).

Neste trabalho objetivou-se avaliar a influência de Spirulina platensis como suplemento alimentar em pós-larvas de tilápia-do-nilo cultivadas em água salina. O delineamento constou de dois tratamentos com três repetições cada. No primeiro os animais foram alimentados com ração contendo o andrógeno 17 a-metiltestosterona e S. platensis e, no segundo, apenas ração com o hormônio. Ao final da reversão (28 dias), as tilápias que receberam S. platensis apresentaram pesos médios de 1,17 ± 0,16 g, resultados superiores significantemente aos dos animais alimentados apenas com ração, os quais alcançaram peso médio de 0,62 ± 0,38 g (P < 0,05). No entanto, as taxas de sobrevivência não tiveram diferença significativa (P < 0,05). Ao final do cultivo (78 dias), a análise gonadal dos peixes evidenciou índices de 47,5% de machos para os peixes cultivados sem a microalga e 59,09% para os peixes cultivados com S. platensis. Com a realização deste trabalho, foi possível concluir que a tilápia-do-nilo apresentou bom desenvolvimento e taxas de sobrevivência mais satisfatórias durante a fase de reversão sexual na presença de S. platensis, em relação àquelas alimentadas apenas com ração, em água salina. No entanto, não foi possível obter índices aceitáveis de reversão sexual após a administração, por meio da ração, do hormônio masculinizante através da ração. PALAVRAS-CHAVES: Microalga, Oreochromis, reversão sexual, salinidade, 17?- metiltestosterona.