No abstract

The aromatic profiles of three white grape varieties (Alvarinho, Loureiro, and Avesso) and two red varieties (Amaral and Vinhão) from the Vinhos Verdes region have been established with respect to the monoterpenic compounds, present either in free and in glycosidically bound fractions. Seventeen compounds have been identified and quantified in the free form and 21 in the glycosidically bound form. Loureiro variety is characterized by important levels of linalool in the free fraction, above the odour perception threshold; in contrast, Alvarinho and Avesso varieties do not contain compounds above the perception threshold. For Alvarinho, geraniol prevails, followed by linalool, while Avesso only has, in much low concentration, geraniol, nerol and citronellol; red varieties do not contain terpenic compounds. Loureiro and Alvarinho are still the richer varieties with regard to the glycosylated fraction; linalool and 3,7-dimethylocta-1,5-dien-3,7-diol have equivalent concentrations, and linalool is around the odour perception threshold; Avesso does not contain linalool. The isomers (Z) and (E) of 8-hydroxylinalool seem to differentiate white varieties; they are similar in Loureiro but the (Z) isomer prevails in Avesso and especially in Alvarinho; Avesso has a more balanced distribution. Amaral only contains ␣-terpineol, nevertheless of similar concentrator found in Loureiro; Vinhão has a more balanced distribution of isomers but the concentrations are very low. The results show that profiles of the terpenic compounds vary to a significant degree for the grape varieties studied and as is already known empirically, the white varieties are richer than red varieties, especially Loureiro.

No abstract

Abstract-Call Level Interfaces (CLI) are low level API aimed at providing services to connect two main components in database applications: client applications and relational databases. Among their functionalities, the ability to manage data retrieved from databases is emphasized. The retrieved data is kept in local memory structures that may be permanently connected to the host database. Client applications, beyond the ability to read their contents, may also execute Insert, Update and Delete actions over the local memory structures, following specific protocols. These protocols are row (tuple) oriented and, while being executed, cannot be preempted to start another protocol. This restriction leads to several difficulties when applications need to deal with several tuples at a time. The most paradigmatic case is the impossibility to cope with concurrent environments where several threads need to access to the same local memory structure instance, each one pointing to a different tuple and executing its particular protocol. To overcome the aforementioned fragility, a Concurrent Tuple Set Architecture (CTSA) is proposed to manage local memory structures. A performance assessment of a Java component based on JDBC (CLI) is also carried out and compared with a common approach. The main outcome of this research is the evidence that in concurrent environments, components relying on the CTSA may significantly improve the overall performance when compared with solutions based on standard JDBC API.