Software patterns to improve knowledge transfer: an experiment.

Patterns for software development have been a hot topic for some time within the object-oriented community. Patterns are part of a software engineering problem-solving discipline. It all started with Design Patterns [11], but gradually patterns were used in a larger number of areas of system development. The goal of patterns within the software community is to create a body of literature to help software developers resolve recurring problems encountered throughout all areas of software development. Patterns help to create a shared language for communicating insight and experience about these problems and their solutions [4]. In this research report, first, a definition of software patterns is given, including some history, an overview of the different kinds of software patterns, the elements of a pattern and the different pattern formats. Secondly, as patterns claim to improve transfer of knowledge, we performed an experiment to test this hypothesis. This experiment is described in Section 2. Finally, Section 3 formulates the conclusions about this experiment.

Handling transactional business services.

This article discusses the handling of transactional business services, which are service compositions that orchestrate and coordinate underlying services to process a high-level business activity. The main contribution made in this article is the presentation of the pattern TBS handler, which describes how one can implement a transactional business service (TBS). This pattern functions as an overview pattern for a complete pattern language that is outlined in the text. This pattern language provides the appropriate ingredients for the implementation of a TBS. It is presented using thumbnails.

Deducing software process improvement areas from a Cocomo II-based productivity measurement.

At the SMEF2006 conference, we presented our experiences with the set-up of a measurement environment using the COCOMO II-model for software development projects in a company in the banking and insurance area. The set-up was part of a larger research project on managing efficiency aspects of software factory systems. One year of measurements later, a database of 22 projects is obtained. In this paper we will present our conclusions and findings after these first measurement results. The effort multipliers in the COCOMO II-model represent the factors that have a linear influence on the amount of effort needed for a project. As such, they are a management instrument that gives an indication which parameters need attention within the company in order to improve the productivity. In this paper, we discuss a new kind of report we constructed in order to visualise the influence of the different effort multipliers. The goal of the report is two folded. Firstly, one can check whether the factors identified by the COCOMO II-model as effort multipliers indeed have an influence on the effort and therefore on the productivity of a project in this company. And secondly, one can check whether the amount of influence identified by the COCOMO II-model is comparable with the influence we detect in the company. As we will show, even though there was only data available of one year of measurement, useful interpretations could already be given to the results as well as indications about which areas of the software development process need to be focused on in order to improve the productivity.

Cocomo II as productivity measurement: a case study at KBC.

Software productivity is generally measured as the ratio of size over effort, whereby several techniques exist to measure the size. In this paper, we propose the innovative approach to use an estimation model as productivity measurement. This approach is applied in a case-study at the ICT-department of a bank and insurance company. The estimation model, in this case Cocomo II, is used as the norm to judge about productivity of application development projects. This research report describes on the one hand the set-up process of the measurement environment and on the other hand the measurement results. To gain insight in the measurement data, we developed a report which makes it possible to identify productivity improvement areas in the development process of the case-study company.

In Vivo screening and discovery of novel candidate thalidomide analogs in the zebrafish embryo and chicken embryo model systems

This study was supported by a Wellcome Trust-NIH PhD Studentship to SB, WDF and NV. Grant number 098252/Z/12/Z. SB, CHC and WDF are supported by the Intramural Research Program, NCI, NIH. NHG and WL are supported by the Intramural Research Program, NIA, NIH.Peer reviewedPublisher PD

Testicular somatic cell-like cells derived from embryonic stem cells induce differentiation of epiblasts into germ cells

Regeneration of the testis from pluripotent stem cells is a real challenge, reflecting the complexity of the interaction of germ cells and somatic cells. Here we report the generation of testicular somatic cell-like cells (TesLCs) including Sertoli cell-like cells (SCLCs) from mouse embryonic stem cells (ESCs) in xeno-free culture. We find that Nr5a1/SF1 is critical for interaction between SCLCs and PGCLCs. Intriguingly, co-culture of TesLCs with epiblast-like cells (EpiLCs), rather than PGCLCs, results in self-organised aggregates, or testicular organoids. In the organoid, EpiLCs differentiate into PGCLCs or gonocyte-like cells that are enclosed within a seminiferous tubule-like structure composed of SCLCs. Furthermore, conditioned medium prepared from TesLCs has a robust inducible activity to differentiate EpiLCs into PGCLCs. Our results demonstrate conditions for in vitro reconstitution of a testicular environment from ESCs and provide further insights into the generation of sperm entirely in xeno-free culture