Mutation testing and self/peer assessment: analyzing their effect on students in a software testing course

Testing is a crucial activity in the development of software systems. With the increasing complexity of software projects, the industry requires incorporating graduates with adequate testing skills and preparation in this field. A challenge in software testing education is to make students perceive the benefits of writing tests and assess their quality with advanced testing techniques. In this paper, we present an experience integrating both mutation testing and self/peer assessment –two of the most used techniques to that end in the past– into a software testing course during three years. This experience allowed us to analyze the effect of applying these strategies on the students’ perception of their manually-written test suites. Noticeably, the computation of the mutation score significantly undermined the initial expectations they had on the developed test suites. Also, the application of peer testing helped them estimate the relative quality of two comparable test suites, as we found a notable correspondence with their respective mutation coverage. Besides, a more in-depth analysis revealed that the students' test suites with more test cases did not always achieve the highest scores, that they found more readable their own tests, and that they tended to cover the basic operations while forgetting about more advanced features. An opinion survey confirmed the impact that the use of mutants had on their perception about testing, and they mostly supported paying a higher level of attention to testing concepts in software engineering degree plans.The work was partially funded by the European Commission (FEDER), the Spanish Ministry of Science, Innovation and Universities under the project FAME (RTI2018-093608-B-C33), the European project ASSETs (612678-EPP-1-2019-1-IT-EPPKA2-SSA-B), and the University of Cádiz

Interactivity in the Generation of Test Cases with Evolutionary Computation

Test generation is a costly but necessary testing activity to increase the quality of software projects. Automated testing tools based on evolutionary computation principles constitute an appealing modern approach to support testing tasks. However, these tools still find difficulties to detect certain types of plausible faults in real-world projects. Besides, recent studies have shown that, in general, automatically-generated tests do not resemble those manually written and, consequently, testers are reluctant to adopt them. We observe two key issues, namely the opacity of the process and the lack of cooperation with the tester, currently hampering the acceptance of automated results. Based on these findings, we explore in this paper how the interaction between current tools and expert testers would help address the test case generation problem. More specifically, we identify a number of interaction opportunities related to the object-oriented test case design driven to boost their readability and detection power. Using EvoSuite as base implementation, we present a proof of concept focused on the possibility to integrate readability assessment of the most promising test suites into a genetic algorithm.Work partially funded by the European Commission (ERDF), the Spanish Ministry of Science, Innovation and Universities [RTI2018-093608-BC33 and RED2018-102472-T], the University of Cordoba (Plan Propio - mod. 2.4), and the University of Malag

Nutrient Use Efficiency of Southern South America Proteaceae Species. Are there General Patterns in the Proteaceae Family?

Plants from the Proteaceae family can thrive in old, impoverished soil with extremely low phosphorus (P) content, such as those typically found in South Western Australia (SWA) and South Africa. The South Western (SW) Australian Proteaceae species have developed strategies to deal with P scarcity, such as the high capacity to re-mobilize P from senescent to young leaves and the efficient use of P for carbon fixation. In Southern South America, six Proteaceae species grow in younger soils than those of SWA, with a wide variety of climatic and edaphic conditions. However, strategies in the nutrient use efficiency of Southern South (SS) American Proteaceae species growing in their natural ecosystems remain widely unknown. The aim of this study was to evaluate nutrient resorption efficiency and the photosynthetic nutrients use efficiency by SS American Proteaceae species, naturally growing in different sites along a very extensive latitudinal gradient. Mature and senescent leaves of the six SS American Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea Lomatia hirsuta, L. ferruginea, and L. dentata), as well as, soil samples were collected in nine sites from southern Chile and were subjected to chemical analyses. Nutrient resorption (P and nitrogen) efficiency in leaves was estimated in all species inhabiting the nine sites evaluated, whereas, the photosynthetic P use efficiency (PPUE) and photosynthetic nitrogen (N) use efficiency (PNUE) per leaf unit were determined in two sites with contrasting nutrient availability. Our study exhibit for the first time a data set related to nutrient use efficiency in the leaves of the six SS American Proteaceae, revealing that for all species and sites, P and N resorption efficiencies were on average 47.7 and 50.6%, respectively. No correlation was found between leaf nutrient (P and N) resorption efficiency and soil attributes. Further, different responses in PPUE and PNUE were found among species and, contrary to our expectations, a higher nutrient use efficiency in the nutrient poorest soil was not found. We conclude that SS American Proteaceae species did not show a general pattern in the nutrient use efficiency among them neither with others Proteaceae species reported in the literature

Adhesion of freshwater sponge cells mediated by carbohydrate-carbohydrate interactions requires low environmental calcium

Marine ancestors of freshwater sponges had to undergo a series of physiological adaptations to colonize harsh and heterogeneous limnic environments. Besides reduced salinity, river-lake systems also have calcium concentrations far lower than seawater. Cell adhesion in sponges is mediated by calcium-dependent multivalent self-interactions of sulfated polysaccharides components of membrane-bound proteoglycans named aggregation factors. Cells of marine sponges require seawater average calcium concentration (10\xC2\xA0mM) to sustain adhesion promoted by aggregation factors. We demonstrate here that the freshwater sponge Spongilla alba can thrive in a calcium-poor aquatic environment and that their cells are able to aggregate and form primmorphs with calcium concentrations 40-fold lower than that required by marine sponges cells. We also find that their gemmules need calcium and other micronutrients to hatch and generate new sponges. The sulfated polysaccharide purified from S. alba has sulfate content and molecular size notably lower than those from marine sponges. Nuclear magnetic resonance analyses indicated that it is composed of a central backbone of non- and 2-sulfated \xCE\xB1- and \xCE\xB2-glucose units decorated with branches of \xCE\xB1-glucose. Assessments with atomic force microscopy/single-molecule force spectroscopy show that S. alba glucan requires 10-fold less calcium than sulfated polysaccharides from marine sponges to self-interact efficiently. Such an ability to retain multi-cellular morphology with low environmental calcium must have been a crucial evolutionary step for freshwater sponges to successfully colonize inland waters

Scientific Hybrid Realtiy Environments (SHyRE): Bringing Field Work into the Laboratory

The use of analog environments in preparing for future planetary surface exploration is key in ensuring we both understand the processes shaping other planetary surfaces as well as develop the technology, systems, and concepts of operations necessary to operate in these geologic environments. While conducting fieldwork and testing technology in relevant terrestrial field environments is crucial in this development, it is often the case that operational testing requires a time-intensive iterative process that is hampered by the rigorous conditions (e.g. terrain, weather, location, etc.) found in most field environments. Additionally, field deployments can be costly and must be scheduled months in advance, therefore limiting the testing opportunities required to investigate and compare science operational concepts to only once or twice per year

Mutation‐inspired symbolic execution for software testing

Software testing is a complex and costly stage during the software development lifecycle. Nowadays, there is a wide variety of solutions to reduce testing costs and improve test quality. Focussing on test case generation, Dynamic Symbolic Execution (DSE) is used to generate tests with good structural coverage. Regarding test suite evaluation, Mutation Testing (MT) assesses the detection capability of the test cases by introducing minor localised changes that resemble real faults. DSE is however known to produce tests that do not have good mutation detection capabilities: in this paper, the authors set out to solve this by combining DSE and MT into a new family of approaches that the authors call Mutation‐Inspired Symbolic Execution (MISE). First, this known result on a set of open source programs is confirmed: DSE by itself is not good at killing mutants, detecting only 59.9% out of all mutants. The authors show that a direct combination of DSE and MT (naive MISE) can produce better results, detecting up to 16% more mutants depending on the programme, though at a high computational cost. To reduce these costs, the authors set out a roadmap for more efficient versions of MISE, gaining its advantages while avoiding a large part of its additional costs

Association of tumor necrosis factor alpha-308 promoter polymorphism with spondyloarthritides patients in Colombia

Q3Q2Comunicación corta2195-2197The pathogenesis of SpA is considered to be a complex and multi-factorial process and, similar to other autoimmune diseases, includes the activity of proinflammatory cytokines such as TNF alpha. Our study compared the -308 promoter polymorphism of TNF alpha with TNF alpha levels, HLA-B27 status, age at the onset of symptoms, SpA subtype and the clinical degree of activity in Colombian SpA patients and healthy subjects (HS). Comparisons of the TNF alpha-308A genotype among HS and SpA patients (P = 0.004), uSpA patients (P = 0.040), ReA patients (P = 0.001), were significantly different and AS patients (P = 0.110), as were alleles for SpAs (P = 0.007) between patients with SpAs and controls. Initial exploratory analyses demonstrated that the TNF alpha-308 SNP genotype frequencies were different among SpA patients and HS in the Colombian population studied. Furthermore, there was no significant correlation with activity and functional clinical index, serum TNF alpha level or HLA B27 status. Allele frequencies, on the other hand, were correlated with the activity clinical index