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Abscisic acid (ABA) is one of plant hormones, playing essential roles in developmental regulation and stress signal transduction pathways, such as seed dormancy, seed germination, and environmental stress responses, etc. In recent years, the ABA 8'-hydroxylase was considered to play key role for ABA degradation. Arabidopsis P450 CYP707A subfamily genes were identified by reverse genetic approach to encode ABA 8'-hydroxylases (Kushiro et al., 2004; Saito et al., 2004). CYP707A subfamily includes four members in Arabidopsis, named CYP707A1 (At4g19230), CYP707A2 (At2g29090), CYP707A3 (At5g45340), and CYP707A4 (At3g19270). CYP707A genes were up-regulated by ABA, salinity, drought and osmotic stresses (Saito et al., 2004). However, there are no reports available about the interaction between CYP707A transcripts and cold stress. [ABSTRACT FROM AUTHOR]

The interest in, and user demand for, temporal databases have only increased with time; unfortunately, DBMS vendors and standard groups have not moved aggressively to extend their systems with support for transaction-time or valid-time. This can be partially attributed to the expected major R&D costs to add temporal support to RDBMS by directly extending the database engine. The newly introduced SQL:2003 standards have actually significantly enhanced our ability to support temporal applications in commercial database systems. The long recognized problem of coalescing, which is difficult to support in the framework of SQL:1992, can now be effectively supported in RDBMS. In this paper, we investigate alternatives of temporal coalescing queries under temporal data models in RDBMS. We provide an SQL:2003-based query algorithm and a native relational user defined aggregates (UDA) approach - both approaches only require a single scan of the database. We conclude that temporal queries can be best supported by OLAP functions supported in the current SQL:2003 standards. These new findings demonstrate that the current RDBMS are mature enough to directly support efficient temporal queries, and provide a new paradigm for temporal database research and implementation. [ABSTRACT FROM AUTHOR]

Normally the microarray data contain a large number of genes (usually more than 1000) and a relatively small number of samples (usually fewer than 100). This makes the discriminant analysis of DNA microarray data hard to handle. Selecting important genes to the discriminant problem is hence of much practically significance in microarray data analysis. If put in the context of pattern classification, gene selection can be casted as a feature selection problem. Feature selection approaches are broadly grouped into filter and wrapper methods. The wrapper method outperforms the filter method in general. However the accuracy of wrapper methods is coupled with intensive computations. In present study, we proposed a wrapper-based gene selection algorithm by employing the Regularization Network as the classifier. Compared with classical wrapper method, the computational costs in our gene selection algorithm is significantly reduced, because the evaluation criterion we used does not demand repeated trainings in the leave-one-out procedure. [ABSTRACT FROM AUTHOR]

Automatic memory management has been prevalent on memory / computation constraint systems. Previous research has shown strong interest in small memory footprint, garbage collection (GC) pause time and energy consumption, while performance was left out of the spotlight. This fact inspired us to design memory management techniques delivering high performance, while still keeping space consumption and response time under control. XAMM is an attempt to answer such a quest. Driven by the design decisions above, XAMM implements a variety of novel techniques, including object model, heap management, allocation and GC mechanisms. XAMM also adopts techniques that can not only exploit the underlying system's capabilities, but can also assist the optimizations by other runtime components (e.g. code generator). This paper describes these techniques in details and reports our experiences in the implementation. We conclude that XAMM demonstrates the feasibility to achieve high performance without breaking memory constraints. We support our claims with evaluation results, for a spectrum of real-world programs and synthetic benchmarks. For example, the heap placement optimization can boost the system-wide performance by as much as 10%; the lazy and selective location bits management can reduce the execution time by as much as 14%, while reducing GC pause time on average by as much as 25%. The sum of these techniques improves the system-wide performance by as much as 56%. [ABSTRACT FROM AUTHOR]

A closer integration of XML and database systems is actively pursued by researchers and vendors because of the many practical benefits it offers. Additional special benefits can be achieved on temporal information management - an important application area that represents an unsolved challenge for relational databases [1]. Indeed, XML data model and query languages support: Temporally grouped representations that have long been recognized as a natural data model for historical information [2], and Turing-complete query languages, such as XQuery [3], where all the constructs needed for temporal queries can be introduced as user-defined libraries, without requiring extensions to existing standards. By contrast, the flat relational tables of traditional DBMSs are not well-suited for temporally grouped representations [4]; moreover, significant extensions are required to support temporal information in SQL and, in the past, they were poorly received by SQL standard committees. We will show that (i) XML hierarchical structure can naturally represent the history of databases and XML documents via temporally-grouped data models, and (ii) powerful temporal queries can be expressed in XQuery without requiring any extension to current standards. This approach is quite general and, in addition to the evolution history of databases, it can be used to support the version history of XML documents for transaction-time, valid-time, and bitemporal chronicles [5]. We will demo the queries discussed in [5] and show that this approach leads to simple programming environments that are fully-integrated with current XML tools and commercial DBMSs. [ABSTRACT FROM AUTHOR]