8 research outputs found

    On Modeling the Behavior of Comparators for Complex Fuzzy Objects in a Fuzzy Object-Relational Database Management System

    No full text
    This paper proposes a parameterized definition for fuzzy comparators on complex fuzzy datatypes like fuzzy collections with conjunctive semantics and fuzzy objects. This definition and its implementation on a Fuzzy Object-Relational Database Management System (FORDBMS) provides the designer with a powerful tool to adapt the behavior of these operators to the semantics of the considered application

    Using a Fuzzy Object-Relational Database

    No full text
    The paper presents a fuzzy database management system, and a fuzzy method for dominant colour description of images, on which an image retrieval system is built. The paper shows the suitability of the fuzzy database management system for this kind of applications when the images are characterized by fuzzy data. The synergy of these two introduced components, improves traditional image retrieval systems in three aspects: natural and automatic image description, a natural and easy query language, and high performance in query resolution

    The Alleviation of the Adverse Effects of Salt Stress in the Tomato Plant by Salicylic Acid Shows A Time- and Organ-Specific Antioxidant Response

    No full text
    In the last decade contradictory results have been published as to whether exogenous salicylic acid (SA) can increase salt stress tolerance in cultivated plants by inducing an antioxidant response. Salt stress injury in tomato was mitigated only in cases when the plant was hardened with a high concentration of SA (~10-4 M), low concentrations were ineffective. An efficient accumulation of Na+ in older leaves is a well-known response to salt stress in tomato plants (Solanum lycopersicum cv. Rio fuego) but it remains largely unexplored whether young and old leaves or root tissues have a distinct antioxidant status during salt stress after hardening with 10-7 M or 10-4 M SA. The determination of superoxide dismutase (SOD) and catalase (CAT) activity revealed that the SAinduced transient increases in these enzyme activities in young leaf and/or root tissues did not correlate with the salt tolerance of plants. Salt stress resulted in a tenfold increase in ascorbate peroxidase (APX) activities of young leaves and significant increases in APX and glutathione reductase (GR) activities of the roots hardened with 10-4 M SA. Both total ascorbate (AsA) and glutathione pools reached their highest levels in leaves after 10-7 M SA pre-treatment. However, in contrast to the leaves, the total pool of AsA decreased in the roots under salt stress and thus, due to low APX activity, active oxygen species were scavenged by ascorbate non-enzymatically in these tissues. The increased GR activities in the roots after treatment with 10-4 M SA enabled plants to enhance the reduced glutathione (GSH) pool and maintain the redox status of AsA under high salinity, which led to increased salt tolerance
    corecore