Debating the OO debate: where is the problem?

Abstract: In this paper we discuss problems related to the teaching of object-oriented programming (OOP). We argue that more research on how the computer science teacher understands OOP would be beneficial. Our argument takes its point of departure in three sets of studies: (1) an ongoing study on how computer science teachers understand core concepts of OOP, (2) a study of how the teaching of OOP is discussed within the CS community, and (3) a set of studies that discuss the different ways in which CS teachers experience their teaching. This paper reports on an ongoing study of the different ways in which computing science teachers understand object- oriented programming, and what they mean when use the term objects first.. The phenomenographic research approach has been applied to the analysis of a discussion that occurred in the SIGCSE-members mailing list. Two understandings of objects first have been identified: (1) as an extension of imperative programming, and (2) as conceptually different from imperative programming. These two understandings are illustrated via the differing ways in which computing science teachers use the term polymorphism

Minimal Mark-Up of multiple choice exams using XML

We describe a minimal XML mark-up for multiple choice exams. In our system, exams may be generated at anytime, by choosing a subset of questions from a pool. Furthermore, the system randomises the order of the choices within each chosen question. Thus a student may sit the exam many times. Our first version of this system has been described elsewhere. In this paper, we discuss the limitations of our first system that led to our current work, and give a description of the new system features, including XML tags for supporting collaborative authoring

The Many Ways of the BRACElet Project

This paper provides a retrospective snapshot of the first two years of a multi-institutional multi-national study (MIMN) in Computer Science Education called the BRACElet Project. This study has been inquiring into how novice programmers comprehend and write computer programs. The context for the study is outlined, together with details of how it has evolved and those who have participated. Some challenges encountered during the project are highlighted and pointers for the successful conduct of such a study are provided. The paper concludes by noting pitfalls to be avoided, some open research questions, and current plans for furthering the project

An architecture for systematic tracking of skills and competence level progression in computer science

A typical Computer Science degree is three to five years long, consists of four to six subjects per semester, and two semesters per year. A student enrolled in such a degree is expected to learn both discipline-specific skills and transferable generic skills. These skills are to be taught in a progressive sequence through the duration of the degree. As the student progresses through the subjects and semesters of a degree, his skill portfolio and competence level for each skill is expected to grow. Effectively modeling these curriculum skills, mapping them to assessment tasks across subjects of a degree, and measuring the progression in learner competence level is, largely, still an unsolved problem. Previous work at this scale is limited. This systematic tracking of skills and competence is crucial for effective quality control and optimization of degree structures. Our main contribution is an architecture for a curriculum information management system to facilitate this systematic tracking of skill and competence level progression in a Computer Science context

Benefits and risks of the hormetic effects of dietary isothiocyanates on cancer prevention

The isothiocyanate (ITC) sulforaphane (SFN) was shown at low levels (1-5 µM) to promote cell proliferation to 120-143% of the controls in a number of human cell lines, whilst at high levels (10-40 µM) it inhibited such cell proliferation. Similar dose responses were observed for cell migration, i.e. SFN at 2.5 µM increased cell migration in bladder cancer T24 cells to 128% whilst high levels inhibited cell migration. This hormetic action was also found in an angiogenesis assay where SFN at 2.5 µM promoted endothelial tube formation (118% of the control), whereas at 10-20 µM it caused significant inhibition. The precise mechanism by which SFN influences promotion of cell growth and migration is not known, but probably involves activation of autophagy since an autophagy inhibitor, 3-methyladenine, abolished the effect of SFN on cell migration. Moreover, low doses of SFN offered a protective effect against free-radical mediated cell death, an effect that was enhanced by co-treatment with selenium. These results suggest that SFN may either prevent or promote tumour cell growth depending on the dose and the nature of the target cells. In normal cells, the promotion of cell growth may be of benefit, but in transformed or cancer cells it may be an undesirable risk factor. In summary, ITCs have a biphasic effect on cell growth and migration. The benefits and risks of ITCs are not only determined by the doses, but are affected by interactions with Se and the measured endpoint

Primary ovarian cancer chemotherapy: current standards of care

Chemotherapy has been regarded as standard therapy for the majority of women with advanced epithelial ovarian cancer for several decades, with this role filled largely by the alkylating agents — used as monotherapy — until the mid-1980s. The activity of cisplatin in this disorder was established during the 1970s, and combinations of cisplatin and an alkylating agent were widely used during the late 1980s. However, further research prompted by continuing concerns over poor survival and tolerability led to the adoption of paclitaxel in combination with either cisplatin or carboplatin as first-line therapy in ovarian cancer during the 1990s. Most recent research has focused on further optimisation of these regimens to maximise clinical benefit while minimising toxicity, and investigations into alternative taxanes (e.g. docetaxel), other novel agents and new treatment schedules are ongoing

Measurement of CP-violation asymmetries in D0 to Ks pi+ pi-

We report a measurement of time-integrated CP-violation asymmetries in the resonant substructure of the three-body decay D0 to Ks pi+ pi- using CDF II data corresponding to 6.0 invfb of integrated luminosity from Tevatron ppbar collisions at sqrt(s) = 1.96 TeV. The charm mesons used in this analysis come from D*+(2010) to D0 pi+ and D*-(2010) to D0bar pi-, where the production flavor of the charm meson is determined by the charge of the accompanying pion. We apply a Dalitz-amplitude analysis for the description of the dynamic decay structure and use two complementary approaches, namely a full Dalitz-plot fit employing the isobar model for the contributing resonances and a model-independent bin-by-bin comparison of the D0 and D0bar Dalitz plots. We find no CP-violation effects and measure an asymmetry of ACP = (-0.05 +- 0.57 (stat) +- 0.54 (syst))% for the overall integrated CP-violation asymmetry, consistent with the standard model prediction.Comment: 15 page