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151.
Jiehong Guo Amina Salamova Marta Venier Helena Dryfhout-Clark Nick Alexandrou Sean Backus Lisa Bradley Hayley Hung Ronald A. Hites 《Journal of Great Lakes research》2018,44(4):670-681
We calculated the wet and dry deposition, vapor absorption, and volatilization flows (in kg/yr) of seven polychlorinated biphenyls (PCBs), nine organochlorine pesticides, and two polycyclic aromatic hydrocarbons (PAHs) into and out of the Great Lakes during 2010–2015 (inclusive). Particle, vapor, and precipitation concentrations from five rural and remote stations (one site on each lake) and two urban sites, operated by the United States and Canada, were used for the flow calculations. Output from the water to the air was the most important process for PCBs, chlordanes, and p,p′-DDE. The flows of endosulfan, p,p′-DDT, and phenanthrene were dominated by vapor absorption from the air to the water. The flow of benzo[a]pyrene was controlled by wet and dry deposition to the water. The flows of the hexachlorocyclohexanes (HCHs) into and out of the lakes were about equal, indicating air-water equilibrium for these compounds. Among the lakes, Lakes Superior and Erie had the highest input and output flows. The input and output flows for the five lakes were decreasing with halving times of 1–10 years and 10–40 years, respectively. Most chemicals had seasonal variations in their flows, with maximum inputs in the summer and maximum outputs in the fall. The flows of PCBs and PAHs into Lakes Michigan and Erie were associated with Chicago and Cleveland, respectively. Combining our data with previous data over the period 1992–2015, we estimated that the input flows of most of these chemicals have significantly decreased, but the output flows do not show consistent trends. 相似文献
152.
Stefano Mantegna Arianna Binello Luisa Boffa Marta Giorgis Clara Cena Giancarlo Cravotto 《Food chemistry》2012,130(3):746-750
The ultrasound-assisted extraction (UAE) of resveratrol and other polyphenols from Polygonum cuspidatum has been carried out with the aim of developing an efficient and eco-friendly extraction process. The finely milled roots were sonicated (titanium horn, 19.5 kHz) in methanol, in different cyclodextrin water solutions [β-cyclodextrin (β-CD) or hydroxypropyl β-CD (HPβ-CD)] and also in pure water. UAE dramatically increased the yields and cut down extraction times compared to conventional extraction under stirring. Outstanding results have been achieved with the β-CD solution (1.5% w/w); in fact HPLC analysis showed that the selective inclusion properties of CDs toward phenolic stilbenes gave a much cleaner analytical extract profile. This green method gave 7.51 mg of total resveratrol (free + cleaved polydatin glucoside) per gram of dry plant. Thanks to polyphenol encapsulation within CDs, this extract showed excellent water dispersibility, higher stability and an antioxidant power which is comparable to that of the MeOH extract (DPPH, ORACFL). These important features should pave the road for its application in food supplements or phytochemical preparations. 相似文献
153.
Marta Oliveira Susana Casal Simone Morais Cláudia Alves Filipa Dias Sandra Ramos Eulália Mendes Cristina Delerue-Matos M. Beatriz P.P. Oliveira 《Food chemistry》2012,130(3):702-709
The present paper reports the amount and estimated daily mineral intake of nine elements (Ca, Mg, K, Na, P, Fe, Mn, Cr and Ni) in commercial instant coffees and coffee substitutes (n = 49). Elements were quantified by high-resolution continuum source flame (HR-CS-FAAS) and graphite furnace (HR-CS-GFAAS) atomic absorption spectrometry, while phosphorous was evaluated by a standard vanadomolybdophosphoric acid colorimetric method.Instant coffees and coffee substitutes are rich in K, Mg and P (>100 mg/100 g dw), contain Na, Ca and Fe in moderate amounts (>1 mg/100 g), and trace levels of Cr and Ni. Among the samples analysed, plain instant coffees are richer in minerals (p < 0.001), except for Na and Cr. Blends of coffee substitutes (barley, malt, chicory and rye) with coffee (20–66%) present intermediate amounts, while lower quantities are found in substitutes without coffee, particularly in barley.From a nutritional point of view the results indicate that the mean ingestion of two instant beverages per day (total of 4 g instant powder), either with or without coffee, cannot be regarded as important sources of minerals to the human diet, although providing a supplementation of some minerals, particularly Mg and Mn in instant coffees. Additionally, and for authentication purposes, the correlations observed between some elements and the coffee percentage in the blends, with particular significance for Mg amounts, provides a potential tool for the estimation of coffee in substitute blends. 相似文献
154.
Ferré-Huguet N Nadal M Schuhmacher M Domingo JL 《Environmental science & technology》2006,40(1):61-66
The purpose of this study was to assess the environmental impact of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in the vicinity of a new hazardous waste incinerator (HWI) 4 years after regular operation of the facility. A double approach was carried out. The PCDD/F congener profiles corresponding to environmental samples, soil and herbage, collected before the HWI (baseline) and 4 years after starting regular operations, as well as PCDD/F profiles of air emission samples, were compared. The potential health risks (carcinogenic and noncarcinogenic) due to PCDD/F exposure were assessed for adults and children living in the neighborhood of the facility. Human exposure to PCDD/Fs was mainly due to dietary food intake. Comparisons between the PCDD/F congener profiles corresponding to the baseline and current surveys, as well as data concerning the human health risk assessment, indicate that the HWI in question does not cause additional risks to the environment orto the population living in the vicinity of the facility. 相似文献
155.
Paula Saá Ibusquiza Juan J.R. HerreraDaniel Vázquez-Sánchez Marta L. Cabo 《Food Control》2012,25(1):202-210
Comparison between the resistance to BAC and the microscopic structure between mixed-species biofilms formed by different strains of Listeria monocytogenes and Pseudomonas putida CECT 845 under different scenarios and that obtained by the corresponding monospecies L. monocytogenes biofilm was carried out. The association of P. putida with L. monocytogenes quickens biofilm formation and increases significantly (p < 0.05) the BAC-resistance of the biofilm after 4 days of incubation at 25 °C respecting to that formed by monospecies biofilms. According with the adherence profiles of P. putida, two different patterns of association between both species (A and B) were identified, being type A pattern found in the mixed biofilms much more resistant to BAC. After 11 days of incubation, a destructuration of mixed biofilms occurred in all experimental assays, being in 2 out of 5 experimental cases (4032 and BAC-adapted 5873 on polypropylene) accompanied by a sharp decrease in the number of adhered cells. Microscopic analyses demonstrated that complex three-dimensional microscopic structure showed the highest resistance to BAC (4032-SS). Obtained results clearly highlight that to improve disinfection protocols for assuring food safety, it is necessary to mimick those bacterial association that occur in nature. 相似文献
156.
Tomas Herraiz Guillermo Reglero Pedro J Martin-Alvarez Marta Herraiz Maria D Cabezudo 《Journal of the science of food and agriculture》1991,55(1):103-116
Aroma components of ine resulting from fermentation of grape must from the Verdejo cultivar ere isolated by continuous liquid-liquid extraction and further fractionation on a silica gel column. One hundred and thirty-to substances, including alcohols, esters, carbonyl compounds, terpenes, acids and sulphur compounds, ere identified by using GC-MS; some had not been previously detected in ines. Data are given hich could lead to the characterisation of the Verdejo cultivar and the effect of the elaboration of young ines. The sensory contribution of some volatile compounds to the flavour of Verdejo ine is also studied. 相似文献
157.
Gano-Overway Lori A.; Newton Maria; Magyar T. Michelle; Fry Mary D.; Kim Mi-Sook; Guivernau Marta R. 《Canadian Metallurgical Quarterly》2009,45(2):329
Understanding what factors influence positive youth development has been advocated by youth development researchers (P. L. Benson, 2006; J. S. Eccles & J. A. Gootman, 2002). Consequently, the purpose of this study was to examine whether perceptions of a caring youth sport context influenced prosocial and antisocial behavior through efficacy-related beliefs, that is, positive and negative affective self-regulatory efficacy (ASRE) and empathic self-efficacy (ESE). Multiethnic youths taking part in summer sport programs (N = 395) completed a questionnaire that measured perceptions of the caring climate, ESE, ASRE, and social behavior. Structural equation modeling was used to test whether ASRE and ESE mediated the relationship between caring and social behaviors. Findings revealed that perceptions of caring positively predicted ASRE and ESE. In turn, positive ASRE positively predicted ESE. Prosocial behaviors were positively linked to ESE, whereas antisocial behaviors were negatively predicted by positive ASRE. The results suggest that caring influences prosocial and antisocial behavior because such contexts develop youths' ability to monitor, manage, and control positive affect, which in turn enhances their belief in their ability to empathize. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
158.
Sara Morandi Claudia Focardi Mila Nocentini Marta Puggelli Gabriella Caminati 《Food Analytical Methods》2009,2(4):271-281
The development of a fast and reliable screening method for the determination of tetracycline residues in milk is described
and compared to high-performance liquid chromatography. The method is based on europium-sensitized luminescence: The emissive
properties of the lanthanide cation are used as a fingerprint of europium (III) complexation with tetracycline. The optimization
of the extraction and purification procedures provided a simple and convenient route to prepare stable tetracycline samples
that can safely resist freezing cycles. The method is validated for the first time in milk matrix: The results show that accuracy
and precision of the method meet complaints with the criteria of the Commission Decision 2002/657/EC. The proposed method
has a false compliant rate (β error) lower than 5%. 相似文献
159.
160.