Eye-tracking verification of the strategy used to analyse algorithms expressed in a flowchart and pseudocode

The results of qualitative and quantitative investigations conducted with individuals who learned algorithms in school are presented in this article. In these investigations, eye-tracking technology was used to follow the process of solving algorithmic problems. The algorithmic problems were presented in two comparable variants: in a pseudocode and flowchart. The eye-tracking data resulted in both qualitative (films registering the gaze paths) and quantitative measures, which allowed the detection and interpretation of the differences in the task-solving strategies between those who found the correct answer and those that did not. The results confirmed a hypothesis that use of the formal notation characteristic of a programming language for presenting algorithms is often a practical difficulty in the process of solving even simple tasks. This study opens a new direction of research; they show that eye-tracking technology can be used to optimise the educational process of learning programming.     

Modeling parameters that characterize pacing of elite female 800-m freestyle swimmers

Pacing offers a potential avenue for enhancement of endurance performance. We report here a novel method for characterizing pacing in 800-m freestyle swimming. Websites provided 50-m lap and race times for 192 swims of 20 elite female swimmers between 2000 and 2013. Pacing for each swim was characterized with five parameters derived from a linear model: linear and quadratic coefficients for effect of lap number, reductions from predicted time for first and last laps, and lap-time variability (standard error of the estimate). Race-to-race consistency of the parameters was expressed as intraclass correlation coefficients (ICCs). The average swim was a shallow negative quadratic with slowest time in the eleventh lap. First and last laps were faster by 6.4% and 3.6%, and lap-time variability was ±0.64%. Consistency between swimmers ranged from low-moderate for the linear and quadratic parameters (ICC = 0.29 and 0.36) to high for the last-lap parameter (ICC = 0.62), while consistency for race time was very high (ICC = 0.80). Only ~15% of swimmers had enough swims (~15 or more) to provide reasonable evidence of optimum parameter values in plots of race time vs. each parameter. The modest consistency of most of the pacing parameters and lack of relationships between parameters and performance suggest that swimmers usually compensated for changes in one parameter with changes in another. In conclusion, pacing in 800-m elite female swimmers can be characterized with five parameters, but identifying an optimal pacing profile is generally impractical.     

Language Attitudes and Community Engagement: Diwan–The Breton Immersion High School Through the Eyes of Its Pupils

This article is based on long-term participant observation and interviews with pupils and graduates of the Diwan immersion high school in Brittany, France. With reference to the theory of communities of practice, this article shows how the education in the Breton immersion school can influence a knowledge of the minority language and the young peoples’ engagement with the protection of the Breton language. This article presents the social and cultural capital received through the learning of the Breton language; the distinction between Diwan pupils and people from outside the community; and the gradual formation of a collective new Breton-speakers identity. The sociolinguistic prognostic shows that in a few dozen years the only Breton speakers will be Breton learners. The use of Breton depends thus on having knowledge of it and on finding a community in which this language acts as the benchmark for the creation of a Breton identity.     

Compressed sensing for real measurements of quaternion signals

The paper concerns compressed sensing methods in the quaternion algebra. We prove that it is possible to uniquely reconstruct – by ?₁ norm minimization – a sparse quaternion signal from a limited number of its real linear measurements, provided the measurement matrix satisfies so-called restricted isometry property with a sufficiently small constant. We also provide error estimates for the approximated reconstruction of a non-sparse quaternion signal from noisy and noiseless data.     

Plasma centrifugation does not influence thrombin-antithrombin and plasmin-antiplasmin levels but determines platelet microparticles count

Introduction

Centrifugation is an essential step for plasma preparation to remove residual elements in plasma, especially platelets and platelet-derived microparticles (PMPs). Our working hypothesis was that centrifugation as a preanalytical step may influence some coagulation parameters.

Materials and methods

Healthy young men were recruited (N = 17). For centrifugation, two protocols were applied: (A) the first centrifugation at 2500 x g for 15 min and (B) at 2500 x g for 20 min at room temperature with a light brake. In protocol (A), the second centrifugation was carried out at 2500 x g for 15 min, whereas in protocol (B), the second centrifugation involved a 10 min spin at 13,000 x g. Thrombin-antithrombin (TAT) and plasmin-antiplasmin (PAP) complexes concentrations were determined by enzyme-linked immunosorbent assays. PMPs were stained with CD41 antibody and annexin V, and analyzed by flow cytometry method. Procoagulant activity was assayed by the Calibrated Automated Thrombogram method as a slope of thrombin formation (CAT velocity).

Results

Median TAT and PAP concentrations did not differ between the centrifugation protocols. The high speed centrifugation reduced the median (IQR) PMP count in plasma from 1291 (841-1975) to 573 (391-1010) PMP/µL (P = 0.001), and CAT velocity from 2.01 (1.31-2.88) to 0.97 (0.82-1.73) nM/min (P = 0.049). Spearman’s rank correlation analysis showed correlation between TAT and PMPs in the protocol A plasma which was (rho = 0.52, P < 0.050) and between PMPs and CAT for protocol A (rho = 0.74, P < 0.050) and protocol B (rho = 0.78, P < 0.050).

Conclusion

Centrifugation protocols do not influence the markers of plasminogen (PAP) and thrombin (TAT) generation but they do affect the PMP count and procoagulant activity.Key words: cell-derived microparticles, blood coagulation tests, centrifugation, preanalytical phase     

The Ethos of Science in Contemporary Poland

Modern science is moving away from Michael Polanyi’s vision of ‘the Republic of Science’ and gradually becoming subordinate to political and economic social institutions. This process is accompanied by changes in the normative structure of science. Poland provides an interesting case for empirical study of the scientific ethos mostly because in a relatively short time it experienced a significant reform of the science system, especially in terms of evaluating and financing scientific work. In this paper we examine whether different sets of values and norms are embedded into the normative structure of science in contemporary Poland. The results of a representative survey conducted among 801 researchers were examined with the use of confirmatory factor analysis and fuzzy clustering. The statistical analysis revealed a great complexity in the normative structure of science that goes beyond the expectations formulated on the basis of the theories reviewed. We identified three distinctive groups of researchers, guided by different sets of values and norms in their professional conduct (academic science, post-academic science and the industrial science) and a cluster of researchers with an unidentified system of principles. We argue that the complexity of the normative structure of science should be taken into account in the decision-making regarding any future reforms of the science system.

     

On the numerical competence of six-years-old children

The paper presents some of the results obtained in the course of experiments which have provided evidence of a considerable degree of numerical competence exhibited by six-years-olds and of their fairly advanced activity in discovering and dealing with arithmetical problems.The children used both counting and non-counting ways for solving arithmetical problems. They applied them elastically and interchangeably, often combining them into mutually complementary patterns of finding solutions.