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71.
Climate anomalies and the increasing risk of Vibrio parahaemolyticus and Vibrio vulnificus illnesses
Jaime Martinez-Urtaza John C. Bowers Joaquin Trinanes Angelo DePaola 《Food research international (Ottawa, Ont.)》2010,43(7):1780-1790
We examined the potential influence of climate anomalies in expanding the geographical and seasonal range of seafood-borne illnesses from Vibrio parahaemolyticus and Vibrio vulnificus. Archived climate data from areas of implicated seafood production were obtained from various sources, including in situ monitoring devices and satellite imagery. The geographical expansion of V. parahaemolyticus outbreaks into Peru and Alaska corresponded closely with climate anomalies such as El Niño, which brought large masses of abnormally warm water into these regions. Seasonal expansion of V. vulnificus illnesses associated with oysters harvested from the Gulf of Mexico in April and November correspond with warmer water temperatures (>20 °C) recorded during these months since 1998. This retrospective review indicates that climate anomalies have already greatly expanded the risk area and season for vibrio illnesses and suggest that these events can be forecasted. Certainly, when similar circumstances occur in the future, adjustments in industry practices and regulatory policy should be considered, especially for seafood that is consumed raw, such as bivalve mollusks. 相似文献
72.
Eugenia I. Papagiannakopoulou Maria N. Koukovini Georgios V. Lioudakis Joaquin Garcia-Alfaro Dimitra I. Kaklamani Iakovos S. Venieris Frédéric Cuppens Nora Cuppens-Boulahia 《Computers & Electrical Engineering》2013
In this paper, we introduce a new access control model that aims at addressing the privacy implications surrounding network monitoring. In fact, despite its importance, network monitoring is natively leakage-prone and, moreover, this is exacerbated due to the complexity of the highly dynamic monitoring procedures and infrastructures, that may include multiple traffic observation points, distributed mitigation mechanisms and even inter-operator cooperation. Conceived on the basis of data protection legislation, the proposed approach is grounded on a rich in expressiveness information model, that captures all the underlying monitoring concepts along with their associations. The model enables the specification of contextual authorisation policies and expressive separation and binding of duty constraints. Finally, two key innovations of our work consist in the ability to define access control rules at any level of abstraction and in enabling a verification procedure, which results in inherently privacy-aware workflows, thus fostering the realisation of the Privacy by Design vision. 相似文献
73.
Jose Luis Amorós Arnaldo Moreno Encarna Blasco Joaquin Javier Pérez Sandra Navarro Sandra Reverter 《International Journal of Applied Ceramic Technology》2019,16(6):2153-2160
Inkjet technology has become very popular in recent years and is nowadays widely used for decorating ceramic products. This has led to in-depth study of the operating principles and process variables involved. These notably influence the properties of the deposited ink layers, as do the physicochemical properties of the applied inks and of the glazes on which the inks are deposited. The problems associated with these factors are further heightened when inks with complex formulations designed to obtain special effects and specific surface properties are used. This study examines the characteristics of the interface that developed on applying an ink on a certain type of glaze, as well as the surface properties of the final product. The relationship of the amount of ink applied per unit area and the particle size distribution (PSD) of the glaze on which it was deposited to ink penetration into the glaze layer was also investigated. The resulting microstructures were observed by SEM, while the variation of glaze layer composition with distance to the surface was determined by SEM-EDS. The results obtained were successfully correlated with the porous texture of the unfired glaze (determined by SEM and mercury porosimetry) and with unfired glaze PSD. 相似文献
74.
Joaquin Angulo Beate Hiller Martha Olivera Liliana Mahecha Dirk Dannenberger Gerd Nuernberg Bernd Losand Karin Nuernberg 《Journal of the science of food and agriculture》2012,92(15):2968-2974
BACKGROUND: The present study investigated tissue‐specific responses of muscle and mammary gland to a 10 week intervention of German Holstein cows (n = 18) with three different dietary fat supplements (saturated fat; linseed oil or sunflower oil plus docosahexaenoic acid‐rich algae) by analysing fatty acid profiles and quality parameters of meat and milk. RESULTS: Plant oil/algae intervention affected neither fat content nor quality parameters of meat but decreased fat content and saturated fatty acid amounts of milk. Linseed oil/algae intervention caused significantly higher concentrations of C18:3n‐3 (meat, 1.0 g per 100 g; milk, 1.2 g per 100 g) and C22:6n‐3 (meat, 0.3 g per 100 g; milk, 0.14 g per 100 g). Sunflower oil/algae intervention increased n‐6 fatty acid contents in milk (4.0 g per 100 g) but not in meat. Elevated amounts of C18:1trans isomers and C18:1trans‐11 were found in meat and especially in milk of plant oil/algae‐fed cows. C18:1cis‐9 amounts were found to be increased in milk but decreased in meat after plant oil/algae intervention. CONCLUSION: The present study demonstrated that dietary fatty acid manipulation substantially shifted the fatty acid profiles of milk and to a lesser extent of meat, whereas meat quality traits were not affected. Indications of tissue‐specific responses of mammary gland and muscle were identified. Copyright © 2012 Society of Chemical Industry 相似文献
75.
Ana M. González-Paramás Fátima Lopes da SilvaGlenda Macz-Pop Susana González-ManzanoCristina Alcalde-Eon José Joaquin Pérez-AlonsoM.Teresa Escribano-Bailón Julián C. Rivas-GonzaloCelestino Santos-Buelga 《Food chemistry》2006
Pigments resulting from the direct condensation of anthocyanins and flavanols are usually associated with reactions taking place during processing and storage of plant-derived foods and beverages and have been particularly studied in aged red wines. In this paper, small amounts of flavanol–anthocyanin condensed pigments are found in different plant extracts. Structures are suggested for 10 such condensed pigments detected in extracts of strawberry, runner beans, purple corn and grape skins, based on their MSn fragmentation patterns, following analyses by electrospray tandem mass spectrometry. All of them correspond to dimers containing a flavan-3-ol [either (epi)afzelechin, (epi)catechin or (epi)gallocatechin] as the upper unit carbon–carbon linked to a lower anthocyanin unit consisting of different delphinidin, cyanidin, pelargonidin, peonidin or malvidin derivatives. The detection of these pigments in plant extracts may suggest that they are natural pigments and not products exclusively formed during storage and ageing of processed foods and beverages, as was previously assumed. 相似文献
76.
Flores-Conde MI Reyes L Herrera R Rios H Vazquez MA Miranda R Tamariz J Delgado F 《International journal of molecular sciences》2012,13(3):2590-2617
Infrared irradiation promoted the Diels-Alder cycloadditions of exo-2-oxazolidinone dienes 1-3 with the Knoevenagel adducts 4-6, as dienophiles, leading to the synthesis of new 3,5-diphenyltetrahydrobenzo[d]oxazol-2-one derivatives (7, 9, 11 and 13-17), under solvent-free conditions. These cycloadditions were performed with good regio- and stereoselectivity, favoring the para-endo cycloadducts. We also evaluated the one-pot three-component reaction of active methylene compounds 20, benzaldehydes 21 and exo-2-oxazolidinone diene 2 under the same reaction conditions. A cascade Knoevenagel condensation/Diels-Alder cycloaddition reaction was observed, resulting in the final adducts 13-16 in similar yields. These procedures are environmentally benign, because no solvent and no catalyst were employed in these processes. The regioselectivity of these reactions was rationalized by Frontier Molecular Orbital (FMO) calculations. 相似文献
77.
Gumulya Y Sanchis J Reetz MT 《Chembiochem : a European journal of chemical biology》2012,13(7):1060-1066
Directed evolution is a method to tune the properties of enzymes for use in organic chemistry and biotechnology, to study enzyme mechanisms, and to shed light on darwinian evolution in nature. In order to enhance its efficacy, iterative saturation mutagenesis (ISM) was implemented. This involves: 1) randomized mutation of appropriate sites of one or more residues; 2) screening of the initial mutant libraries for properties such as enzymatic rate, stereoselectivity, or thermal robustness; 3) use of the best hit in a given library as a template for saturation mutagenesis at the other sites; and 4) continuation of the process until the desired degree of enzyme improvement has been reached. Despite the success of a number of ISM-based studies, the question of the optimal choice of the many different possible pathways remains unanswered. Here we considered a complete 4-site ISM scheme. All 24 pathways were systematically explored, with the epoxide hydrolase from Aspergillus niger as the catalyst in the stereoselective hydrolytic kinetic resolution of a chiral epoxide. All 24 pathways were found to provide improved mutants with notably enhanced stereoselectivity. When a library failed to contain any hits, non-improved or even inferior mutants were used as templates in the continuation of the evolutionary pathway, thereby escaping from the local minimum. These observations have ramifications for directed evolution in general and for evolutionary biological studies in which protein engineering techniques are applied. 相似文献
78.
Synthesis of monolayer hexagonal boron nitride on Cu foil using chemical vapor deposition 总被引:2,自引:0,他引:2
Kim KK Hsu A Jia X Kim SM Shi Y Hofmann M Nezich D Rodriguez-Nieva JF Dresselhaus M Palacios T Kong J 《Nano letters》2012,12(1):161-166
Hexagonal boron nitride (h-BN) is very attractive for many applications, particularly, as protective coating, dielectric layer/substrate, transparent membrane, or deep ultraviolet emitter. In this work, we carried out a detailed investigation of h-BN synthesis on Cu substrate using chemical vapor deposition (CVD) with two heating zones under low pressure (LP). Previous atmospheric pressure (AP) CVD syntheses were only able to obtain few layer h-BN without a good control on the number of layers. In contrast, under LPCVD growth, monolayer h-BN was synthesized and time-dependent growth was investigated. It was also observed that the morphology of the Cu surface affects the location and density of the h-BN nucleation. Ammonia borane is used as a BN precursor, which is easily accessible and more stable under ambient conditions than borazine. The h-BN films are characterized by atomic force microscopy, transmission electron microscopy, and electron energy loss spectroscopy analyses. Our results suggest that the growth here occurs via surface-mediated growth, which is similar to graphene growth on Cu under low pressure. These atomically thin layers are particularly attractive for use as atomic membranes or dielectric layers/substrates for graphene devices. 相似文献
79.
Cordero M. Isabel; Merino J. Joaquin; Sandi Carmen 《Canadian Metallurgical Quarterly》1998,112(4):885
A role for corticosterone in the consolidation of contextual fear conditioning has previously been proposed. In this study, physiological evidence was found to support this view. The extent of conditioned fear and the levels of plasma corticosterone in rats, after context exposure at training and at different posttraining times (24 hr and 7 days), depended on the intensity of the unconditional stimulus (footshock). In each experimental session, a positive correlation was found between the magnitude of corticosterone levels and the fear-related behavioral inhibition exhibited in the context. Results support the involvement of corticosterone on the processes that occur during consolidation in determining the strength at which the contextual fear conditioning is stored as a long-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
Felix L Elorza Antonio Jimnez‐Caliani Silvia Jimnez‐Jorge Maria C Naranjo Latifa Naji Maria I Estevez Jose M Mateos‐Romero Joaquin Mateo Juan M Guerrero 《Journal of the science of food and agriculture》2004,84(7):613-615
Moderate intake of sherry by rats resulted in a decrease in serum total cholesterol and an increase in the proportion of high‐density lipoprotein cholesterol. Oloroso, manzanilla, fino and amontillado sherries all exerted similar effects. These effects were apparently not related to the ethanol content, since an aqueous solution of ethanol did not modify cholesterol levels. Therefore other compounds must be responsible for the effects observed. This paper shows that, in addition to typical red and white wines, sherries should be included in the list of wines with beneficial physiological effects following moderate consumption. Copyright © 2004 Society of Chemical Industry 相似文献