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141.
Applications of an oak extract on Petit Verdot grapevines. Influence on grape and wine volatile compounds 总被引:1,自引:0,他引:1
Ana M. Martínez-Gil Teresa Garde-CerdánAmaya Zalacain Ana I. Pardo-GarcíaM. Rosario Salinas 《Food chemistry》2012
Petit Verdot vineyards were treated at veraison with a commercial aqueous French oak extract in order to determine if the extract’s volatile components can be transferred to grapes and then to wines. Three different formulations (25% (one application), 25% (four applications) and 100%) were tested, together with an eugenol and guaiacol standard solution to better follow their behaviour. The volatile compounds of treated grapes and their wines after alcoholic and malolactic fermentation and after 8 months were analysed by stir bar sorptive extraction and gas chromatography mass spectrometry (SBSE-GC–MS). The results showed that the grapes stored the volatile compounds mainly as non-volatile precursors, and some of these were released after winemaking. In the case of wines, it was possible to distinguish the control versus the ones from vineyard treatments. The different oak extract applications were evident only after alcoholic fermentation sampling, making it very interesting for young wines. 相似文献
142.
Xavier Lladó Arnau Oliver Mariano Cabezas Jordi Freixenet Joan C. Vilanova Ana Quiles Laia Valls Lluís Ramió-Torrentà Àlex Rovira 《Information Sciences》2012,186(1):164-185
Automatic segmentation of multiple sclerosis (MS) lesions in brain MRI has been widely investigated in recent years with the goal of helping MS diagnosis and patient follow-up. However, the performance of most of the algorithms still falls far below expert expectations. In this paper, we review the main approaches to automated MS lesion segmentation. The main features of the segmentation algorithms are analysed and the most recent important techniques are classified into different strategies according to their main principle, pointing out their strengths and weaknesses and suggesting new research directions. A qualitative and quantitative comparison of the results of the approaches analysed is also presented. Finally, possible future approaches to MS lesion segmentation are discussed. 相似文献
143.
Ana Rita Otrelo-Cardoso Márcia Alexandra da Silva Correia Viola Schwuchow Dmitri I. Svergun Maria Jo?o Rom?o Silke Leimkühler Teresa Santos-Silva 《International journal of molecular sciences》2014,15(2):2223-2236
The periplasmic aldehyde oxidoreductase PaoABC from Escherichia coli is a molybdenum enzyme involved in detoxification of aldehydes in the cell. It is an example of an αβγ heterotrimeric enzyme of the xanthine oxidase family of enzymes which does not dimerize via its molybdenum cofactor binding domain. In order to structurally characterize PaoABC, X-ray crystallography and small angle X-ray scattering (SAXS) have been carried out. The protein crystallizes in the presence of 20% (w/v) polyethylene glycol 3350 using the hanging-drop vapour diffusion method. Although crystals were initially twinned, several experiments were done to overcome twinning and lowering the crystallization temperature (293 K to 277 K) was the solution to the problem. The non-twinned crystals used to solve the structure diffract X-rays to beyond 1.80 Å and belong to the C2 space group, with cell parameters a = 109.42 Å, b = 78.08 Å, c = 151.77 Å, β = 99.77°, and one molecule in the asymmetric unit. A molecular replacement solution was found for each subunit separately, using several proteins as search models. SAXS data of PaoABC were also collected showing that, in solution, the protein is also an αβγ heterotrimer. 相似文献
144.
Marta Pérez Pérez Ana María Serrano Bedia María Concepción López Fernández 《国际生产研究杂志》2016,54(10):3133-3148
The present work is an attempt to contribute to the conceptual systematisation of the manufacturing flexibility types by synthesising the vast literature available after a systematic review. We classified the papers in two perspectives (hierarchical and strategic), and engaged in a systematic process of standardisation of the definitions and names of various flexibility types leading to a better understanding of them. This process allowed us to clearly show: (a) the existence of a broader consensus in the field than expected; (b) that problems are limited to concrete aspects related to the level of analysis or the scope of certain flexibility types; (c) the possibility of a theoretical integration between the two perspectives which would permit a standardisation of the names and definitions for the flexibility types which make up the manufacturing flexibility construct. 相似文献
145.
Ignacio Montero Ana Herrero M. Carmen Mendoza Rosaura Rodicio M. Rosario Rodicio 《Food research international (Ottawa, Ont.)》2012,45(2):1025-1029
During a screening of Salmonella enterica in foods of animal origin four isolates of serovar Typhimurium carrying hybrid virulence-resistance plasmids were detected. Three of them, one from pork and two from chicken meat, contained pUO-StVR2, a derivative of the pSLT virulence plasmid with the blaOXA-1, catA1, aadA1, sulI and tet(B) genes, which confer resistance to ampicillin, chloramphenicol, streptomycin-spectinomycin, sulfonamides and tetracycline, respectively. The fourth isolate, from pork, harbored a pUO-StVR2 variant (termed ν8) with an additional dfrA10 gene responsible for resistance to trimethoprim. This gene is part of the orf513-dfrA10-qacEΔ1-sul1 element characteristically found in complex class 1 integrons. Pulsed-field gel electrophoresis identified two XbaI-BlnI combined profiles: X2-B2 generated from the three pUO-StVR2 isolates, and X12-B17 shown by the pUO-StVR2-ν8 isolate. The same profiles have also been found in clinical and ill pig isolates, supporting chicken and pork meat as vehicles for transmission of Typhimurium carrying pUO-StVR2-like plasmids. 相似文献
146.
Ana Dolores Santiago de Freitas Everardo Valadares Sá Barretto de Sampaio Bárbara Laine Ribeiro da Silva Jarcilene Silva de Almeida Cortez R?mulo Sim?es Cezar Menezes 《Nutrient Cycling in Agroecosystems》2012,94(2-3):181-192
Although biological nitrogen fixation (BNF) is considered the main input of N in mature and regenerating native tropical vegetation, it has seldom been quantified. Biomass and N accumulation and fixation were determined for spontaneously occurring herbaceous species in caatinga areas in four regeneration stages (2, 17, 39 and >50?years after abandonment from agricultural use). BNF was estimated using the 15N natural-abundance method. The 2-year regeneration area had the highest total herb (6,355?kg?ha?1) and legume (262?kg?ha?1) biomass production, N stocks (82?kg?ha?1) and fixed N (5.0?kg?ha?1). N2-fixing legumes (nine species in the sampled area) contributed over 97?% of legume biomass in all areas. Macroptilium gracile added the largest amount of N (3.9?kg?ha?1 in the 2-year regeneration area) because of its large biomass production (205?kg?ha?1), although it was not the species with the highest proportion of fixed N (76?%). All of the N2-fixing species obtained large proportions of their N from symbiosis, most of them more than 50?%.However, the amounts of fixed N per unit area were relatively low (0.22?C5.00?kg?ha?1) because the biomass of N2-fixing species was always less than 5?% of the total herb biomass. 相似文献
147.
Ana M. Bernardos David Gómez José R. Casar 《International journal of human-computer interaction》2016,32(4):325-351
Pointing is one of the more meaningful gestures in human expression. In this article, deictic and head pose pointing methods are evaluated as interaction means, with the objective of comparing their efficiency and delivered comfort, usability, and user experience to apply them to the deployment of services in smart spaces. Standard tools and questionnaires are applied in a user study with 20 individuals who have tried a Kinect V2-enabled pointing system to a) complete a multidirectional International Organization for Standardization (ISO) 9241-9 pointing task and b) test a service to command smart objects. The results show that both deictic and head pose interaction perform in a similar way, providing a throughput of 2.14 and 2.04 bits/s, respectively (comparable to joysticks or touchpads in equivalent ISO tasks). The system being quite robust to the user position in the Kinect coverage area, target size influences performance, but also learnability and the overall response when cursor visual cues are not available. From comfort, usability, and user experience responses, it can be said that deictic is perceived to perform better than head pose in terms of accuracy, efficiency, and organization, although head pose is preferred for its speed. 相似文献
148.
Alberto Gutierrez-Escolar Ana Castillo-Martinez Jose M. Gomez-Pulido Jose-Maria Gutierrez-Martinez Esteban Patricio Dominguez González-Seco Zlatko Stapic 《Energy Efficiency》2017,10(2):265-282
There are very few countries that have provisions addressing the energy efficiency of the whole street lighting system, such as Spain or the Netherlands. Nevertheless, there is not an agreement about how energy efficiency must be assessed. The Spanish Government contemplates it in the Royal Decree 1890/2008 with the goal of improving energy savings and efficiency. However, this has not obtained the expected results. Nowadays, energy efficiency of this kind of systems is assessed using a label. In the case of Spain, this label only assesses one magnitude. The contributions of this paper are two evaluation systems (kiviat diagram and pie chart) which assess five magnitudes: lamps, energy efficiency index, light pollution, renewable energy contribution, and harness of the luminous flux using dimming. After that, a survey was done to study several subjects: (1) if citizens are aware about the efficiency of street lighting systems, (2) whether the sample of colors used in the label is adequate, and (3) if our proposed systems could replace the current evaluation system. Finally, the paper finishes with the conclusions of the survey. 相似文献
149.
Lipolysis,lipid peroxidation and texture of Serrano ham processed under different ripening temperature conditions
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Ana del Olmo Javier Calzada Manuel Nuñez 《International Journal of Food Science & Technology》2016,51(8):1793-1800
Lipolysis, lipid peroxidation, texture and rancid taste were investigated in Serrano hams processed under low, medium and high ripening temperature conditions (RTC) for 15 months. Medium RTC hams showed the highest contents of saturated and monounsaturated free fatty acids (FFAs) from month 5 to 15 and of polyunsaturated FFAs from month 7 to 12. The primary peroxidation index decreased during ripening in all hams, with higher levels for low RTC hams from month 5 onwards. Contrarily, the secondary peroxidation index increased during ripening in all hams, with higher levels for medium RTC hams from month 7 onwards. Texture parameters varied significantly among ham muscles. Shear force increased during ripening in all hams, with higher values for medium RTC hams, whereas cutting force was not influenced by RTC or ripening time. Rancid taste scarcely developed during ripening and was not affected by RTC. 相似文献