897 resultados para Fruit-fly


Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this study a citrate-buffered version of QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method for determination of 14 organochlorine pesticides (OCPs) residues in tamarind peel, fruit and commercial pulp was optimized using gas chromatography (GC) coupled with electron-capture detector (ECD) and confirmation by GC tandem mass spectrometry (GC–MS/MS). Five procedures were tested based on the original QuEChERS method. The best one was achieved with increased time in ultrasonic bath. For the extract clean-up, primary secondary amine (PSA), octadecyl-bonded silica (C18) and magnesium sulphate (MgSO4) were used as sorbents for tamarind fruit and commercial pulp and for peel was also added graphitized carbon black (GCB). The samples mass was optimized according to the best recoveries (1.0 g for peel and fruit; 0.5 g for pulp). The method results showed the matrix-matched calibration curve linearity was r2 > 0.99 for all target analytes in all samples. The overall average recoveries (spiked at 20, 40 and 60 μg kg−1) have been considered satisfactory presenting values between 70 and 115% with RSD of 2–15 % (n = 3) for all analytes, with the exception of HCB (in peel sample). The ranges of limits of detection (LOD) and quantification (LOQ) for OCPs were for peel (LOD: 8.0–21 μg kg−1; LOQ: 27–98 μg kg−1); for fruit (LOD: 4–10 μg kg−1; LOQ: 15–49 μg kg−1) and for commercial pulp (LOD: 2–5 μg kg−1; LOQ: 7–27 μg kg−1). The method was successfully applied in tamarind samples being considered a rapid, sensitive and reliable procedure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Spleen cells from mice were examined at 5, 10, 15, 20 and 25 days post-infection (dpi) with Dermatobia hominis larva and at 5, 10, 15, 30 and 60 days post-larval emergence (dple). Cell proliferation in vitro assays were carried out with RPMI-1640 medium and larval secretory product (LSP) of D. hominis at 5, 10, 15, 20 and 25 days. When each group of mice was tested against each medium, significance was only seen for 25 dpi, with increasing order: LSP-10 d, -25 d, -5 d, -20 d, -15 d and RPMI. Significant results were also observed when each medium was tested against mice at each dpi or dple. Each dple group vs. each medium produced significant results only for 10 dple, with increasing order: LSP-5 d, -20 d, -25 d, -10 d, -15 d and RPMI. Comparative tests were also carried out between groups to refine certain observations. The LSPs were also analyzed using SDS-PAGE. The results prove that myiasis caused depletion of spleen cells, particularly under the effect of the LSP-10 and -15, but the cells tended to increase up to 60 dple. This in vitro assay may represent the real systemic immune response in the relationship LSP-D. hominis-host.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of the study was to report the first occurrence of the parasitoid Brachymeria podagrica in pupae of Ophyra aenescens, a fly of medical-sanitary importance. Human feces was used as bait to collect the insects. In the study 20 pupae of Ophyra aenescens (Wiedemann) (Diptera: Muscidae) were obtained, of which 20% of the total yielded the parasitoid Brachymeria podagrica (Hymenoptera: Chalcididae).

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This study focuses on the assessment of the fermentation conditions required to modulate the metabolic flux in the osmotolerant yeast Candida magnoliae and evaluate its potential to produce low-alcoholic and low-caloric fermented beverages. For that purpose, two strains, PYCC 2903 and PYCC 3191, were used and fermentation conditions as oxygenation, sugar concentration and the ratio of glucose to fructose were studied using synthetic culture media. Candida magnoliae PYCC 2903 was subsequently used to ferment real industrial fructose-rich substrates such as fruit juices. Sugar consumption profiles for C.magnoliae PYCC 2903 incubated aerobically in the presence of high fructose and glucose concentrations (15%, 10% and 5%) showed a selective utilization of fructose, denoting a preference for this sugar over glucose. The lower ratio between ethanol and sugar alcohols yield was obtained for both strains incubated under oxygen limitation simulating industrial fructose-rich substrates, confirming the ability of this yeast to direct fermentation towards alternative products. Enzymatic assays for hexokinase activity in terms of capacity and affinity for glucose and fructose were performed, aiming to elucidate its contribution to the fructophilic behaviour of this yeast. Enzymatic assays for both strains showed that the Vmax is two to threefold higher for fructose than for glucose but Km is also 10-20-fold higher for this sugar than for glucose. Hence, hexokinase kinetic properties do not explain fructophily in C.magnoliae. This indicates that fructose transport is probably determining in this respect, as observed for other fructophilic yeasts. Fruit juice fermentations with C.magnoliae PYCC 2903 revealed a potential for the production of beverages with interesting sensorial properties. Pear and peach fermentations exhibited the best results with the lowest ratio between ethanol and sugar alcohols yield and the most pleasant organoleptic features.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae) and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania) amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus) as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3%) and Bi flaviscutellata (41.4%), present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania) amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

‘’Fruta com Cheiro’’ is an idea for a new brand of fruit that would be introduced in the Portuguese market that would differentiate itself from the brands already in the market and from other non-branded fruit producers. In order to prove that the idea was valid and would have a place in the market, two methods of exploratory research were used – in-depth interviews and focus groups – to understand attitudes and behaviors regarding fruit selection and purchase and also people’s perceptions to ‘’Fruta com Cheiro’’. After these two steps, several considerations were made in relation to preliminary marketing aspects such as brand creation and positioning. There was also a final remark on the fact that this thesis is not a business plan and its purpose was to show how viable would the project be.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work project regards a challenge presented by a Portuguese organization on the retail sector, SONAEMC, which is a case study of how and why fruit shrinkage occurs in the fruit supply chain within their convenience stores. A qualitative research methodology enabled to infer in which stages throughout the chain shrinkage’s causes occur and, to conclude that internal rules for procedures and processes are not always followed and whose compliance would be enough to reduce fruit shrinkage. The key conclusion is that if fruit stock loss is reduced by as much as 15% the category’s profitability could increase about 8%.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This project has two different goals, one of them is to promote the consumption of exotic fruits with high quality. The other goal of the project is to look for the viability of turning this work project into a real business, focusing in two different channels to diversify its revenues: B2B and B2C. In order to achieve this second goal, this project aims to see the best way to commercialize this product (Lucuma powder and Pulp of Lucuma) and how to make it in an efficient way with right companies. Therefore, the project aims to create a company to commercialize the product between the producers in Peru and possibly small businesses interested in acquire the processed fruit and also individuals interested in own consumption in small quantities. This project, if successful, tries to diversify the consumption into other good organic healthy products in the long-term.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

ABSTRACTINTRODUCTION:The larvicidal activity of oils, fatty acids, and methyl esters of Solanum lycocarpum fruit against Culex quinquefasciatus is unknown.METHODS:The larvicidal activity of samples of ripe and unripe fruit from S. lycocarpum was evaluated against third and fourth instar larvae of C. quinquefasciatus .RESULTS:The oils, fatty acids, and methyl esters of S. lycocarpum showed the greatest larvicidal effect (57.1-95.0%) at a concentration of 100mg/L (LC 50values between 0.70 and 27.54mg/L).CONCLUSIONS:Solanum lycocarpum fruit may be a good source of new natural products with larvicidal activity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A nest of an undescribed species of Euglossa was found inside a fruit of Theobroma subincanum (Sterculiaceae) in the Amazonian rainforest, Ecuador. It contained 3-4 living females and one dead and 37 cells in all. Total length of bee 12.5mm; frons blue-green; thorax blue; abdomen bronze above, green and dark ventrally; and kind tibia blue. Tongue about 11 mm long.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Frutaformas is a Portuguese micro-enterprise, specialized in the production of premium dehydrated-fruit, an emerging snack category fostered by the increasing trend for healthier alimentary habits in developed countries. The relatively small size of the domestic market and the growing competition led Frutaformas to consider Europe as an attractive for export market. A scoring model based on a set of macro and micro-level criteria suggested the United Kingdom as the preferential target country at this stage. Recommendations on the entry mode and the associated risks were elaborated taking into account the country and industry analysis as well as Frutaformas’ unique organizational platform.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Premature degradation of ordinary Portland cement (OPC) concrete infrastructures is a current and serious problem with overwhelming costs amounting to several trillion dollars. The use of concrete surface treatments with waterproofing materials to prevent the access of aggressive substances is an important way of enhancing concrete durability. The most common surface treatments use polymeric resins based on epoxy, silicone (siloxane), acrylics, polyurethanes or polymethacrylate. However, epoxy resins have low resistance to ultraviolet radiation while polyurethanes are sensitive to high alkalinity environments. Geopolymers constitute a group of materials with high resistance to chemical attack that could also be used for coating of concrete infrastructures exposed to harsh chemical environments. This article presents results of an experimental investigation on the resistance to chemical attack (by sulfuric and nitric acid) of several materials: OPC concrete, high performance concrete (HPC), epoxy resin, acrylic painting and a fly ash based geopolymeric mortar. Three types of acids, each with high concentrations of 10%, 20% and 30%, were used to simulate long term degradation by chemical attack. The results show that the epoxy resin had the best resistance to chemical attack, irrespective of the acid type and acid concentration.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Nowadays, the concrete production sector is challenged by attempts to minimize the usage of raw materials and energy consumption, as well as by environmental concerns. Therefore, it is necessary to choose better options, e.g. new technologies or materials with improved life-cycle performance. One solution for using resources in an efficient manner is to close the materials' loop through the recycling of materials that result either from the end-of-life of products or from being the by-product of an industrial process. It is well known that the production of Portland cement, one of the materials most used in the construction sector, has a significant contribution to the environmental impacts, mainly related with carbon dioxide emission. Therefore, the study and utilization of by-products or wastes usable as cement replacement in concrete can supply more sustainable options, provided that these type of concrete produced has same durability and equivalent quality properties as standard concrete. This work studied the environmental benefits of incorporating different percentages of two types of fly ashes that can be used in concrete as cement replacement. These ashes are waste products of power and heat production sectors using coal or biomass as fuels. The results showed that both ashes provide a benefit for the concrete production both in terms of environmental impact minimization and a better environmental performance through an increase in cement replacement. It is possible to verify that the incorporation of fly ashes is a sustainable option for cement substitution and a possible path to improve the environmental performance of the concrete industry.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The incorporation of fly ash (FA) in cementitious matrices have been frequently used in order to make the matrix more resistant to the action of chlorides. On the other hand, it is known that Ca (OH)2 existing in the matrix is partially consumed by the pozzolanic reactions, which facilitates the advancement of carbonation. Given that the combined action between carbonation and chloride penetration is a fact little known, we speculate about the behaviour of the matrix in this context. This study investigates the influence of the presence of chlorides on the carbonation in mortars with FA. Samples with 0% and 40% replacement of cement CEM I 42.5 R for FA were molded with water/binder 0.56 and 0.52 respectively. After 90 days of curing the specimens were subjected to cycles of immersion/drying for 56 days. Half of the samples was subjected to the following cycle: two days in a solution containing NaCl (concentration equal to 3.5 %); 12 days in the carbonation chamber (4% of CO2). The other half was: two days in water; 12 days in the carbonation chamber. Then, the development of carbonation was evaluated. The results indicate that the presence of chlorides influences the carbonation. The specimens submitted to the exclusive action of CO2 showed a greater depth of carbonation compared to that presented by the specimens subjected to combined action. This may be related to changes in properties of the matrix which may lead to further refinement of the pores and related to the presence of the salt that can lead to partial filling of the pores and the increase in moisture content.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The eco-efficient, self-compacting concrete (SCC) production, containing low levels of cement in its formulation, shall contribute for the constructions' sustainability due to the decrease in Portland cement use, to the use of industrial residue, for beyond the minimization of the energy needed for its placement and compaction. In this context, the present paper intends to assess the viability of SCC production with low cement levels by determining the fresh and hardened properties of concrete containing high levels of fly ash (FA) and also metakaolin (MK). Hence, 6 different concrete formulations were produced and tested: two reference concretes made with 300 and 500 kg/m3 of cement; the others were produced in order to evaluate the effects of high replacement levels of cement. Cement replacement by FA of 60% and by 50% of FA plus 20% of MK were tested and the addition of hydrated lime in these two types of concrete were also studied. To evaluate the self-compacting ability slump flow test, T500, J-ring, V-funnel and L-box were performed. In the hardened state the compressive strength at 3, 7, 14, 21, 28 and 90 days of age was determined. The results showed that it is possible to produce low cement content SCC by replacing high levels of cement by mineral additions, meeting the rheological requirements for self-compacting, with moderate resistances from 25 to 30 MPa after 28 days.