We discuss the problem of building domain oriented environments by a composition of heterogeneous application components and tools. We describe several individual tools that support such environments, namely a distributed monitoring and control tool (DAMS), a process-based distributed debugger (PDBG) and a heterogeneous interconnection model (PHIS). We discuss our experience with the development of a Problem Oriented Environment in the domain of genetic algorithms, obtained by a composition of heterogeneous tools and application components.

We discuss debugging prototypes that can easily support new functionalities, depending on the requirements of high-level computational models, and allowing a coherent integration with other tools in a software engineering environment. Concerning the first aspect, we propose a framework that identifies two distinct levels of functionalities that should be supported by a parallel and distributed debugger using: a process and thread-level, and a coordination level concerning sets of processes or threads. An incremental approach is used to effectively develop prototypes that support both functionalities. Concerning the second aspect, we discuss how the interfacing with other tools has influenced the design of a process-level debugging interface (PDBG) and a distributed monitoring and control layer called (DAMS).

An evaluation of the mycological quality of the sand beaches of the Lisboa and Vale do Tejo coastal area in Portugal was undertaken in May-October 1994. The keratinolytic fungi, yeasts, potential pathogenic and allergic and/or environmental saprophytic fungi were analysed. The results for the yeast Candida were evaluated according to the “Proposed Guidelines for the Microbiological Quality of Sand” (Mendes et al., 1993). The data showed good/satisfactory quality of the sand beaches for the genus Candida. The results indicate that the allergic and/or environmental saprophytic fungi were the most common in sand beaches. The fungi Scopulariopsis and the yeast Candida could be used as specific indicator organisms of sand beaches quality. A new quality objective is introduced that will contribute to improve the sand beaches quality.

Most known teaching experiences focus on parallel computing courses only, but some teaching experiences on distributed computing courses have also been reported. In this paper we describe a course on Parallel and Distributed Processing that is taught at undergraduate level in the Computer Science degree of our University.This course presents an integrated approach concerning concurrency, parallelism, and distribution issues. It's a breadth-first course addressing a wide spectrum of abstractions: the theoretical component focus on the fundamental abstractions to model concurrent systems, including process cooperation schemes, concurrent programming models, data and control distribution, concurrency control and recovery in transactional systems, and parallel processing models; the practical component illustrates the design and implementation issues involved in selected topics such as a data and control distribution problem, a distributed transaction-based support system and a parallel algorithm.We also discuss how this approach has been contributing to prepare the student to further actions regarding research and development of concurrent, distributed, or parallel systems.

In this paper we discuss several issues concerning the design and implementation of a debugger for parallel and distributed applications. This debugger uses a client-server approach to isolate the debugging user-interface from the debugging services, by way of a two-level structured approach: the component-level to observe and act upon individual processes; and the coordination-level to observe the interprocess relations and act upon them.

Parallel debugging is complex and difficult. Complex because the programmer has to deal with multiple program flows and process interactions, and difficult due to the very limited choice on effective and easy-to-use debugging tools for parallel programming. Simple and necessary features for parallel debugging are absent even from commercial debuggers, such as a record-replay feature, that allows to re-execute multiple times a parallel application assuring that during each re-execution the internal race conditions are solved in the same way they were in the first time. Some work has been done on record-replay techniques for parallel and distributed applications, but just a few have been applied to specific systems (such as PVM or MPI), and even less have produced working prototypes. In this paper we describe a method designed to work with the PVM system and how it was implemented to provide a working prototype.

In order to address the diversity of existing parallel programming models, it is important to provide development environments that can be incrementally extended with new services. Concerning the debugging of process based models, we have previously designed and implemented a basic interface that can be accessed by other tools as well as by debugging modules associated with high-level programming languages.

This paper describes our experience with the design and implementation of a distributed debugger for C/PVM programs within the scope of the SEPP and HPCTI Copernicus projects. These projects aimed at the development of an integrated parallel software engineering environment based on a high-level graphical parallel programming model (GRAPNEL) and a set of associated tools supporting graphical edition, compilation, simulated and real parallel execution, testing, debugging, performance monitoring, mapping, and load balancing. We discuss how the development of the debugging tool was strongly influenced by the requirements posed by other tools in the environment, namely support for high-level graphical debugging of GRAPNEL programs, and support for the integration of static and dynamic analysis tools. We describe the functionalities of the DDBG debugger and its internal architecture, and discuss its integration with two separate tools in the SEPP/HPCTI environment: the GRED graphical editor for GRAPNEL programs, and the STEPS testing tool for C/PVM programs.

This paper describes our experience with the design and implementation of a distributed debugger for C/PVM programs within the scope of the SEPP and HPCTI Copernicus projects. These projects aimed at the development of an integrated parallel software engineering environment based on a high-level graphical parallel programming model (GRAPNEL) and a set of associated tools supporting graphical edition, compilation, simulated and real parallel execution, testing, debugging, performance monitoring, mapping, and load balancing. We discuss how the development of the debugging tool was strongly influenced by the requirements posed by other tools in the environment, namely support for high-level graphical debugging of GRAPNEL programs, and support for the integration of static and dynamic analysis tools. We describe the functionalities of the DDBG debugger and its internal architecture, and discuss its integration with two separate tools in the SEPP/HPCTI environment: the GRED graphical editor for GRAPNEL programs, and the STEPS testing tool for C/PVM programs.

We discuss the problem of building domain oriented environments by a composition of heterogeneous application components and tools. We describe several individual tools that support such environments, namely a distributed monitoring and control tool (DAMS), a process-based distributed debugger (PDBG) and a heterogeneous interconnection model (PHIS). We discuss our experience with the development of a Problem Oriented Environment in the domain of genetic algorithms, obtained by a composition of heterogeneous tools and application components.

We discuss debugging prototypes that can easily support new functionalities, depending on the requirements of high-level computational models, and allowing a coherent integration with other tools in a software engineering environment. Concerning the first aspect, we propose a framework that identifies two distinct levels of functionalities that should be supported by a parallel and distributed debugger using: a process and thread-level, and a coordination level concerning sets of processes or threads. An incremental approach is used to effectively develop prototypes that support both functionalities. Concerning the second aspect, we discuss how the interfacing with other tools has influenced the design of a process-level debugging interface (PDBG) and a distributed monitoring and control layer called (DAMS).

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Structure and QED effects for 2s1/2 and 2p3/2 levels are calculated for lithiumlike U89+ trough neonlike U82+, lithiumlike Th87+ trough neonlike Th80+ and lithiumlike Bi80+ trough neonlike Bi73+. The results of the first two sets are compared with recent measurements of the 2s1/2-2p3/2 transition energy in 3 to 10-electron ions. Good agreement with experiment is found for most of the observed lines. Forty-one possible transitions are calculated for each ion in the eight ionization states, in the experimental energy range. Twenty-eight of these transitions have not been observed, nor calculated previously. We also calculate transition rates, branching ratios, excitation and ionization cross sections and confirm that the thirteen experimental observed transitions correspond to the ones with highest relative intensities. However, we find nineteen more transitions that could be measured in a more sensitive experiment.X

In this paper we discuss several issues concerning the design and implementation of a debugger for parallel and distributed applications. This debugger uses a client-server approach to isolate the debugging user-interface from the debugging services, by way of a two-level structured approach: the component-level to observe and act upon individual processes; and the coordination-level to observe the interprocess relations and act upon them.

Parallel debugging is complex and difficult. Complex because the programmer has to deal with multiple program flows and process interactions, and difficult due to the very limited choice on effective and easy-to-use debugging tools for parallel programming. Simple and necessary features for parallel debugging are absent even from commercial debuggers, such as a record-replay feature, that allows to re-execute multiple times a parallel application assuring that during each re-execution the internal race conditions are solved in the same way they were in the first time. Some work has been done on record-replay techniques for parallel and distributed applications, but just a few have been applied to specific systems (such as PVM or MPI), and even less have produced working prototypes. In this paper we describe a method designed to work with the PVM system and how it was implemented to provide a working prototype.

In order to address the diversity of existing parallel programming models, it is important to provide development environments that can be incrementally extended with new services. Concerning the debugging of process based models, we have previously designed and implemented a basic interface that can be accessed by other tools as well as by debugging modules associated with high-level programming languages.

This paper describes our experience with the design and implementation of a distributed debugger for C/PVM programs within the scope of the SEPP and HPCTI Copernicus projects. These projects aimed at the development of an integrated parallel software engineering environment based on a high-level graphical parallel programming model (GRAPNEL) and a set of associated tools supporting graphical edition, compilation, simulated and real parallel execution, testing, debugging, performance monitoring, mapping, and load balancing. We discuss how the development of the debugging tool was strongly influenced by the requirements posed by other tools in the environment, namely support for high-level graphical debugging of GRAPNEL programs, and support for the integration of static and dynamic analysis tools. We describe the functionalities of the DDBG debugger and its internal architecture, and discuss its integration with two separate tools in the SEPP/HPCTI environment: the GRED graphical editor for GRAPNEL programs, and the STEPS testing tool for C/PVM programs.

This paper describes our experience with the design and implementation of a distributed debugger for C/PVM programs within the scope of the SEPP and HPCTI Copernicus projects. These projects aimed at the development of an integrated parallel software engineering environment based on a high-level graphical parallel programming model (GRAPNEL) and a set of associated tools supporting graphical edition, compilation, simulated and real parallel execution, testing, debugging, performance monitoring, mapping, and load balancing. We discuss how the development of the debugging tool was strongly influenced by the requirements posed by other tools in the environment, namely support for high-level graphical debugging of GRAPNEL programs, and support for the integration of static and dynamic analysis tools. We describe the functionalities of the DDBG debugger and its internal architecture, and discuss its integration with two separate tools in the SEPP/HPCTI environment: the GRED graphical editor for GRAPNEL programs, and the STEPS testing tool for C/PVM programs.

Conversion of Fe ions in solution to the solid phase in ferritin concentrates iron required for cell function. The rate of the Fe phase transition in ferritin is tissue specific and reflects the differential expression of two classes of ferritin subunits (H and L). Early stages of mineralization were probed by rapid freeze-quench Mossbauer, at strong fields (up to 8 T), and EPR spectroscopy in an H-type subunit, recombinant frog ferritin; small numbers of Fe (36 moles/mol of protein) were used to increase Fe3+ in mineral precursor forms, At 25 ms, four Fe3+-oxy species (three Fe dimers and one Fe trimer) were identified, These Fe3+-oxy species were found to form at similar rates and decay subsequently to a distinctive superparamagentic species designated the ''young core.'' The rate of oxidation of Fe2+ (1026 s(-1)) corresponded well to the formation constant for the Fe3+- tyrosinate complex (920 s(-1)) observed previously [Waldo, G. S., {&} Theil, E. C. (1993) Biochemistry 32, 13261] and, coupled with EPR data, indicates that several or possibly all of the Fe3+-oxy species involve tyrosine. The results, combined with previous Mossbauer studies of Y30F human H-type ferritin which showed decreases in several Fe3+ intermediates and stabilization of Fe2+ [Bauminger, E. R., et al. (1993) Biochem, J. 296, 709], emphasize the involvement of tyrosyl residues in the mineralization of H-type ferritins. The subsequent decay of these multiple Fe3+-oxy species to the superparamagnetic mineral suggests that Fe3+ species in different environments may be translocated as intact units from the protein shell into the ferritin cavity where the conversion to a solid mineral occurs.

To provide high-level graphical support for PVM (Parallel Virtual Machine) based program development, a complex programming environment (GRADE) is being developed. GRADE currently provides tools to construct, execute, debug, monitor and visualise message-passing parallel programs. It offers high-level graphical programming abstraction mechanism to construct parallel applications by introducing a new graphical language called GRAPNEL. GRADE also provides the programmer with the same graphical user interface during the program design and debugging stages. A distributed debugging engine (DDBG) assists the user in debugging GRAPNEL programs on distributed memory computer architectures. Tape/PVM and PROVE support the performance monitoring and visualization of parallel programs developed in the GRADE environment.