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991.
In this work a solution for the problem of the detection of outliers in gas emissions in urban areas that uses functional data analysis is described. Different methodologies for outlier identification have been applied in air pollution studies, with gas emissions considered as vectors whose components are gas concentration values for each observation made. In our methodology we consider gas emissions over time as curves, with outliers obtained by a comparison of curves instead of vectors. The methodology, which is based on the concept of functional depth, was applied to the detection of outliers in gas omissions in the city of Oviedo and results were compared with those obtained using a conventional method based on a comparison of vectors. Finally, the advantages of the functional method are reported. 相似文献
992.
Barrera-Díaz C Lugo-Lugo V Roa-Morales G Natividad R Martínez-Delgadillo SA 《Journal of hazardous materials》2011,185(2-3):1362-1368
In this study we present the cathodic Cr(VI) reduction using electrodissolution of iron anode. In batch experiments we tested four different cathodic materials; the best conditions were found when copper was used. It is observed that when more current is applied into the electrochemical cell faster reduction rates are achieved. Continuous experiments also reveal that Cr(VI) reduction could be done in a very efficient way. To confirm the experimental data, cyclic voltammetry was used and it was found that the cathodic Cr(VI) reduction is taking place. 相似文献
993.
González-Alcaraz MN Conesa HM Tercero Mdel C Schulin R Alvarez-Rogel J Egea C 《Journal of hazardous materials》2011,186(1):805-813
The aim of this study was to evaluate the combined effects of liming and behaviour of Sarcocornia fruticosa as a strategy of phytomanagement of metal polluted salt marsh soils. Soils were taken from two polluted salt marshes (one with fine texture and pH~6.4 and the other one with sandy texture and pH~3.1). A lime amendment derived from the marble industry was added to each soil at a rate of 20 g kg(-1), giving four treatments: neutral soil with/without liming and acidic soil with/without liming. Cuttings of S. fruticosa were planted in pots filled with these substrates and grown for 10 months. The pots were irrigated with eutrophicated water. As expected, lime amendment decreased the soluble metal concentrations. In both soils, liming favoured the growth of S. fruticosa and enhanced the capacity of the plants to phytostabilise metals in roots. 相似文献
994.
Safinya CR Raviv U Needleman DJ Zidovska A Choi MC Ojeda-Lopez MA Ewert KK Li Y Miller HP Quispe J Carragher B Potter CS Kim MW Feinstein SC Wilson L 《Advanced materials (Deerfield Beach, Fla.)》2011,23(20):2260-2270
The review will describe experiments inspired by the rich variety of bundles and networks of interacting microtubules (MT), neurofilaments, and filamentous-actin in neurons where the nature of the interactions, structures, and structure-function correlations remain poorly understood. We describe how three-dimensional (3D) MT bundles and 2D MT bundles may assemble, in cell free systems in the presence of counter-ions, revealing structures not predicted by polyelectrolyte theories. Interestingly, experiments reveal that the neuronal protein tau, an abundant MT-associated-protein in axons, modulates the MT diameter providing insight for the control of geometric parameters in bio- nanotechnology. In another set of experiments we describe lipid-protein-nanotubes, and lipid nano-tubes and rods, resulting from membrane shape evolution processes involving protein templates and curvature stabilizing lipids. Similar membrane shape changes, occurring in cells for the purpose of specific functions, are induced by interactions between membranes and proteins. The biological materials systems described have applications in bio-nanotechnology. 相似文献
995.
Concepción Pintado Alicia de Miguel Olga Acevedo Leonor Nozal José Luis Novella Rafael Rotger 《Food Control》2011,22(3-4):638-642
The presence of pathogenic bacteria in spices represents a public health risk as a possible cause of food contamination. Salmonella has been found in several spices and it has been involved in food-borne outbreaks, but this bacterium has not been reported as a contaminant of saffron (Crocus sativus L.). We examined a possible antibacterial effect of saffron using samples from Iran, Greece and Spain which were artificially contaminated with clinical isolates belonging to five different serovars of Salmonella. We detected a loss of viability during the room-temperature storage of the saffron samples, with bacteria being undetectable at day 16 except in the case of the DT104 strain of the Typhimurium serovar, in all of the samples, and of the Hadar serovar in the Iranian sample, both of which gave negative culture at day 32. The laboratory strain LT2 of the Typhimurium serovar was undetectable at day 4. To gain an insight into the basis for this bactericidal effect, we measured the inhibitory and bactericidal concentrations of safranal and crocin, the main compounds responsible for the flavouring and colouring capabilities of saffron. They were in the order of 8–16 mg/mL and 64–128 mg/mL for safranal and crocin, respectively. These data suggest that these compounds, and probably their chemical relatives, are involved in the antibacterial activity of saffron, and that this effect can significantly reduce the risk of food contamination with Salmonella by this spice. 相似文献
996.
A growing demand for convenient and ready-to-eat products has increased poultry processors' interest in developing consumer-oriented value-added chicken products. In this study, a conjoint analysis survey of 276 chicken consumers in Edmonton was conducted during the summer of 2009 to assess the importance of the chicken part, production method, processing method, storage method, the presence of added flavor, and cooking method on consumer preferences for different value-added chicken product attributes. Estimates of consumer willingness to pay (WTP) premium prices for different combinations of value-added chicken attributes were also determined. Participants'"ideal" chicken product was a refrigerated product made with free-range chicken breast, produced with no additives or preservatives and no added flavor, which could be oven heated or pan heated. Half of all participants on average were willing to pay 30% more for a value-added chicken product over the price of a conventional product. Overall, young consumers, individuals who shop at Farmers' Markets and those who prefer free-range or organic products were more likely to pay a premium for value-added chicken products. As expected, consumers' WTP was affected negatively by product price. Combined knowledge of consumer product attribute preferences and consumer WTP for value-added chicken products can help the poultry industry design innovative value-added chicken products. Practical Application: An optimum combination of product attributes desired by consumers for the development of a new value-added chicken product, as well as the WTP for this product, have been identified in this study. This information is relevant to the poultry industry to enhance consumer satisfaction of future value-added chicken products and provide the tools for future profit growth. 相似文献
997.
998.
Libkind D Moliné M Sommaruga R Sampaio JP van Broock M 《Yeast (Chichester, England)》2011,28(8):619-627
The synthesis of the UV Absorbing compounds named mycosporines (MYCs) has been detected in a few basidiomycetous yeast groups. Conspicuous accumulation of mycosporine-glutaminol-glucoside (MGG) in yeasts requires photo-induction and its photoprotective function has been postulated. The distribution of the ability to produce MYCs appeared to be related to the yeast taxonomic affiliation. In view of the potential significance of MYCs in yeast taxonomy, we here studied the distribution of this trait among dimorphic basidiomycetes of the Pucciniomycotina. Of the 94 fungal species (377 strains and 33 genera) tested, almost half were MYC-positive and MGG was the main compound produced. MGG synthesis was observed for representatives of five of seven Pucciniomycotina classes, indicating that this trait is widely distributed in this group. MGG detection proved useful for the differentiation of species of the polyphyletic genera, such as Rhodotorula and Sporobolomyces, that are phylogenetically separated. MGG quantification and UV tolerance studies in Cystobasidiomycetes supported the idea that the habitat of origin of each strains is important in the level of MGG synthesis and that MYCs have a photoprotective function in yeasts. The taxonomic value of this trait in fungal systematics is discussed. 相似文献
999.
In this paper, active planar waveguides based on the incorporation of CdSe and CdTe nanocrystal quantum dots in a polymer matrix are demonstrated. In the case of doping the polymer with both types of quantum dots, the nanocomposite film guides both emitted colors, green (550?nm, CdTe) and orange (600?nm, CdSe). The optical pumping laser can be coupled not only with a standard end-fire coupling system, but also directing the beam to the surface of the sample, indicating a good absorption cross-section and waveguide properties. To achieve these results, a study of the nanocomposite optical properties as a function of the nanocrystal concentration is presented and the optimum conditions are found for waveguiding. 相似文献
1000.
Lipid-based nanoparticles (LNPs) are widely used for the delivery of drugs and nucleic acids. Although most of them are considered safe, there is confusing evidence in the literature regarding their potential cellular toxicities. Moreover, little is known about the recovery process cells undergo after a cytotoxic insult. We have previously studied the systemic effects of common LNPs with different surface charge (cationic, anionic, neutral) and revealed that positively charged LNPs ((+)LNPs) activate pro-inflammatory cytokines and induce interferon response by acting as an agonist of Toll-like receptor 4 on immune cells. In this study, we focused on the response of human fibroblasts exposed to LNPs and their cellular recovery process. To this end, we used image-based high content analysis (HCA). Using this strategy, we were able to show simultaneously, in several intracellular parameters, that fibroblasts can recover from the cytotoxic effects of (+)LNPs. The use of HCA opens new avenues in understanding cellular response and nanotoxicity and may become a valuable tool for screening safe materials for drug delivery and tissue engineering. 相似文献