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21.
Georgia Ouzounidou Kalliope K. Papadopoulou Maria Asfi Ioanna Mirtziou Fragiskos Gaitis 《International Journal of Food Science & Technology》2013,48(8):1610-1617
Four different chemical treatments, GA3, 1‐MCP, essential oils and nano‐Cu, were applied immediately after harvest to Petroselinum crispum (Mill) plants. The efficacy of the above chemicals on shelf life extension of parsley stored at 5 °C and 20 °C was determined by analysing physiological and biochemical factors that determine quality standards of storage fresh parsley. Nonsprayed parsley revealed the highest loss of weight, ascorbic acid, pigments and an enhancement of CO2 production and lipid peroxidation at 5 °C and 20 °C of storage. Nano‐Cu was more effective for delaying weight loss and revealed a better storage capacity. GA3, 1‐MCP and essential oils sprays were more effective in ascorbic acid retention at 20 °C than at 5 °C, whereas all substances protect samples from lipid peroxidation. Essential oils were more clearly inhibitory towards both total viable counts and yeast infection. Our results suggest that GA3, 1‐MCP, essential oils and Nano‐Cu exert their function through different mechanisms during ripening and could provide an effective and complementary means for maintaining high‐quality parsley leaves after harvest. 相似文献
22.
Antioxidative effect of quercetin was affected differently in neat sunflower oil, in methyl linoleate o/w emulsion and in phospholipid liposomes by the other chain-breaking antioxidants, α-tocopherol, rutin and astaxanthin. Quercetin was better than or comparable to α-tocopherol as an antioxidant in the three lipid systems. The presence of α-tocopherol showed a strong synergistic effect for quercetin in the emulsion, less in the liposomes and a clear antagonistic effect in the neat oil. Astaxanthin, without any effect alone in neat oil or in the liposomes, but with some effect in the emulsion, did not affect quercetin as an antioxidant. Rutin was only effective as an antioxidant in the liposomes where rutin showed clear synergism with quercetin. The interaction of quercetin with the other antioxidants is classified according to the structural organisation of the lipid substrate. 相似文献
23.
Julietta Moustaka Georgia Tanou Ioannis-Dimosthenis Adamakis Eleftherios P. Eleftheriou Michael Moustakas 《International journal of molecular sciences》2015,16(6):13989-14006
Exposure of Arabidopsis thaliana young and mature leaves to the herbicide paraquat (Pq) resulted in a localized increase of hydrogen peroxide (H2O2) in the leaf veins and the neighboring mesophyll cells, but this increase was not similar in the two leaf types. Increased H2O2 production was concomitant with closed reaction centers (qP). Thirty min after Pq exposure despite the induction of the photoprotective mechanism of non-photochemical quenching (NPQ) in mature leaves, H2O2 production was lower in young leaves mainly due to the higher increase activity of ascorbate peroxidase (APX). Later, 60 min after Pq exposure, the total antioxidant capacity of young leaves was not sufficient to scavenge the excess reactive oxygen species (ROS) that were formed, and thus, a higher H2O2 accumulation in young leaves occurred. The energy allocation of absorbed light in photosystem II (PSII) suggests the existence of a differential photoprotective regulatory mechanism in the two leaf types to the time-course Pq exposure accompanied by differential antioxidant protection mechanisms. It is concluded that tolerance to Pq-induced oxidative stress is related to the redox state of quinone A (QA). 相似文献
24.
Histological characterization is used in clinical and research contexts as a highly sensitive method for detecting the morphological
features of disease and abnormal gene function. Histology has recently been accepted as a phenotyping method for the forthcoming
Zebrafish Phenome Project, a large-scale community effort to characterize the morphological, physiological, and behavioral
phenotypes resulting from the mutations in all known genes in the zebrafish genome. In support of this project, we present
a novel content-based image retrieval system for the automated annotation of images containing histological abnormalities
in the developing eye of the larval zebrafish. 相似文献
25.
The Mullins–Sekerka free boundary problem originates from the study of solidification and liquidation of materials where material is transported by diffusion. In the present paper we explore dynamics of bubbles for the Mullins–Sekerka problem. Using a set of ordinary differential equations for the radii and the centers, we numerically simulate the relevant interactions in both “two-dimensional” and “three-dimensional” settings. Our results illustrate how larger bubbles grow at the expense of smaller ones and highlight the role of additional factors such as the initial inter-bubble distance or weak asymmetries in the bubble position in the ensuing dynamics. One novel feature in comparison with earlier works is the possibility to continue for the three-dimensional case the simulation past the points where one of the bubbles disappears. 相似文献
26.
Georgia Gu 《广东包装》2009,(1)
前言
随着生活节奏的加快,人们日益认识到包装对食品、医药、电子等产品的重要性,无论在国际还是国内市场,对产品货架寿命期望值的提高,使得对包装材料的阻隔性要求也越来越高,为了选择合适的包装材料.预测产品的货架寿命,对整体包装渗透性进行测试是生产厂家应该重视的问题,选择了高阻隔材料.并不代表用其做成的整体包装也一定有高阻隔性。本文用奶粉包装袋材料选择的实例来说明整体包装渗透性测试的重要性。 相似文献
27.
Fluid-based Slotting Optimization for Automated Order Picking System with Multiple Dispenser Types 总被引:1,自引:0,他引:1
LIU Peng WU Yaohua ZHOU Chen XU Na School of Control Science Engineering Sh ong University Jinan China School of Industrial Systems Engineering Georgia Institute of Technology Atlanta GA USA Business School Sh ong Jianzhu University Jinan China 《机械工程学报(英文版)》2011,(4):529-538
Slotting strategy heavily influences the throughput and operational cost of automated order picking system with multiple dispenser types, which is called the complex automated order picking system (CAOPS). Existing research either focuses on one aspect of the slotting optimization problem or only considers one part of CAOPS, such as the Low-volume Dispensers, to develop corresponding slotting strategies. In order to provide a comprehensive and systemic approach, a fluid-based slotting strategy is proposed in this paper. The configuration of CAOPS is presented with specific reference to its fast-picking and restocking subsystems. Based on extended fluid model, a nonlinear mathematical programming model is developed to determine the optimal volume allotted to each stock keeping unit (SKU) in a certain mode by minimize the restocking cost of that mode. Conclusion from the allocation model is specified for the storage modules of high-volume dispensers and low-volume dispensers. Optimal allocation of storage resources in the fast-picking area of CAOPS is then discussed with the aim of identifying the optimal space of each picking mode. The SKU assignment problem referring to the total restocking cost of CAOPS is analyzed and a greedy heuristic with low time complexity is developed according to the characteristics of CAOPS. Real life application from the tobacco industry is presented in order to exemplify the proposed slotting strategy and assess the effectiveness of the developed methodology. Entry-item-quantity (EIQ) based experiential solutions and proposed-model-based near-optimal solutions are compared. The comparison results show that the proposed strategy generates a savings of over 18% referring to the total restocking cost over one-year period. The strategy proposed in this paper, which can handle the multiple dispenser types, provides a practical quantitative slotting method for CAOPS and can help picking-system-designers make slotting decisions efficiently and effectively. 相似文献
28.
Workforce population trends have increased the numbers and kinds of culturally diverse people who work together. Researchers in organizational behavior have often examined culture through values; however, cultural values can be based on collections of people other than traditional nation states. A cultural mosaic is presented as a framework to identify demographic, geographic, and associative features underlying culture. An individual's unique collage of multiple cultural identities yields a complex picture of the cultural influences on that person. Developments in chaos and complexity theories are proposed as a theoretical base for study on the complexity of culture at the individual level. Additional developments in network theory serve as a theoretical base for cultural research at the group level. The cultural mosaic is described as a complex system with localized structures, linking cultural tiles in ordered and chaotic ways. Research propositions examining multiple cultural identities at individual and group levels are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
30.
Demetriou Andreas; Efklides Anastasia; Papadaki Maria; Papantoniou Georgia; Economou Andreas 《Canadian Metallurgical Quarterly》1993,29(3):480
Investigated the structure and development of causal–experimental thought. 260 Ss (aged 12–16 yrs) were examined by 3 test batteries. The batteries involved items addressing combinatorial, hypothesis handling, experimentation, and model construction abilities. Confirmatory factor analysis indicated that these abilities, although distinct from each other, do share a common functional core, and they are organized in a higher order causal–experimental specialized structural system. Rasch scaling indicated that these 4 kinds of abilities follow overlapping developmental trajectories. Saltus modeling suggested that development is continuous rather than discontinuous. Individual differences were found in the rate of acquisition but not in the structure of abilities. A model of synergic developmental causality was proposed to account for this pattern of development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献