Minding mathematicians’ discourses in investigations of their feedback on students’ proofs: a case study

Educational Studies in Mathematics - This article presents a research apparatus for investigating and making sense of stories that emerge from feedback that mathematicians provide on...     

The Role of Attention in the Development of Short-Term Memory: Age Differences in the Verbal Span of Apprehension

In previous studies of memory span, participants have attended to the stimuli while they were presented, and therefore have had the opportunity to use a variety of mnemonic strategies. In the main portion of the present study, participants (first- and fourth-grade children, and adults; 24 per age group) carried out a visual task while hearing lists of spoken digits and received a post-list digit recall cue only occasionally, for some lists. Under these conditions, list information presumably must be extracted from a passively held store such as auditory sensory memory. The results suggest that each individual has a core memory capacity limit that can be observed clearly in circumstances in which it cannot be supplemented by mnemonic strategies, and that the capacity limit appears to increase with age during childhood. Other, attention-demanding processes also contribute to memory for attended lists.     

Reaching a decision to change vocation: a qualitative study of former priests’ experiences

The aim of this study was to explore experiences of Roman Catholic clergy who relinquish the priesthood. Ten former priests participated in semi-structured interviews that were subjected to interpretative phenomenological analysis. Overall, the study found that priests experienced needs and aspirations conflicting with their social role and the expectations made of them. They found making decisions about vocational change frustrating and stressful because of concerns about breaking community norms, fear of social stigma, and disbelief in their ability to cope in lay life. Specific guidelines for supporting priests through counseling psychologists are provided.     

Optimal non-parametric tuning of PID controllers based on classification of shapes of oscillations in modified relay feedback test

In this work, tuning rules of the PID controller have been developed by categorizing a system's response into distinct classes. The classes are formed using the shapes of the test oscillations induced by the system under the Modified Relay Feedback Test (MRFT) produced by specific system models. It is proposed that a physical system can be categorized into one of the proposed classes and thus the tuning rules for a particular class can apply to any kind of system from this class. The idea of producing tuning rules that are based on the shape of the oscillations induced in the loop containing the process comes from the observations that oscillatory responses of physical systems reveal just a few different shapes depending on system dynamics. For applying the developed optimal tuning rules for an arbitrary system, first, certain system characteristics are determined using a priori knowledge of the class model. Then the system's response with the application of the MRFT is examined to classify the oscillation waveform/shape. In this work, such classification is carried out using a cross-correlation algorithm. Finally, a class tuning rules are applied.     

Measurement of fluid flow generated by artificial cilia

We observed and measured the fluid flow that was generated by an artificial cilium. The cilium was composed of superparamagnetic microspheres, in which magnetic dipole moments were induced by an external magnetic field. The interaction between the dipole moments resulted in formation of long chains-cilia, and the same external magnetic field was also used to drive the cilia in a periodic manner. Asymmetric periodic motion of the cilium resulted in generation of fluid flow and net pumping of the surrounding fluid. The flow and pumping performance were closely monitored by introducing small fluorescent tracer particles into the system. By detecting their motion, the fluid flow around an individual cilium was mapped and the flow velocities measured. We confirm that symmetric periodic beating of one cilium results in vortical motion only, whereas asymmetry is required for additional translational motion. We determine the effect of asymmetry on the pumping performance of a cilium, verify the theoretically predicted optimal pumping conditions, and determine the fluid behaviour around a linear array of three neighbouring cilia. In this case, the contributions of neighbouring cilia enhance the maximal flow velocity compared with a single cilium and contribute to a more uniform translational flow above the surface.     

Knowledge spillovers through human mobility across national borders: Evidence from Zhongguancun Science Park in China

This paper investigates the impact of returnee entrepreneurs and their knowledge spillovers on innovation in high-tech firms in China. Using panel data for 1318 high-tech firms in Beijing Zhongguancun Science Park (ZSP) we find that returnee entrepreneurs create a significant spillover effect that promotes innovation in other local high-tech firms. The extent of this spillover effect is positively moderated by the non-returnee firm's absorptive capacity approximated by the skill level of employees. Multinational enterprises’ R&D activities positively affect the innovation intensity of non-returnee firms only when these local firms possess the sufficient level of absorptive capacity. Our findings have important implications for policy-makers and practitioners.     

Students’ Understanding of the Special Theory of Relativity and Design for a Guided Visit to a Science Museum

The present paper describes the design of teaching materials that are used as learning tools in school visits to a science museum. An exhibition on ‘A century of the Special Theory of Relativity’, in the Kutxaespacio Science Museum, in San Sebastian, Spain, was used to design a visit for first‐year engineering students at the university and assess the learning that was achieved. The first part of the paper presents the teaching sequence that was designed to build a bridge between formal teaching and the exhibition visit. The second part analyses the potential of the exhibition and the aforementioned teaching sequence to influence the students’ knowledge of three aspects of the Special Theory of Relativity. The results obtained show that the design of the visit, with both pre‐visit and follow‐up activities, was effective as a means of increasing students’ understanding and stimulating their ability to argue scientifically.     

Dissecting success stories on mathematical problem posing: a case of the Billiard Task

“Success stories,” i.e., cases in which mathematical problems posed in a controlled setting are perceived by the problem posers or other individuals as interesting, cognitively demanding, or surprising, are essential for understanding the nature of problem posing. This paper analyzes two success stories that occurred with individuals of different mathematical backgrounds and experience in the context of a problem-posing task known from past research as the Billiard Task. The analysis focuses on understanding the ways the participants develop their initial ideas into problems they evaluate as interesting ones. Three common traits were inferred from the participants' problem-posing actions, despite individual differences. First, the participants relied on particular sets of prototypical problems, but strived to make new problems not too similar to the prototypes. Second, exploration and problem solving were involved in posing the most interesting problems. Third, the participants' problem posing involved similar stages: warming-up, searching for an interesting mathematical phenomenon, hiding the problem-posing process in the problem's formulation, and reviewing. The paper concludes with remarks about possible implications of the findings for research and practice.     

The Effect of High School Socioeconomic Status on the Predictive Validity of SAT Scores and High School Grade‐Point Average

Research has often found that, when high school grades and SAT scores are used to predict first‐year college grade‐point average (FGPA) via regression analysis, African‐American and Latino students, are, on average, predicted to earn higher FGPAs than they actually do. Under various plausible models, this phenomenon can be explained in terms of the unreliability of predictor variables. Attributing overprediction to measurement error, however, is not fully satisfactory: Might the measurement errors in the predictor variables be systematic in part, and could they be reduced? The research hypothesis in the current study was that the overprediction of Latino and African‐American performance occurs, at least in part, because these students are more likely than White students to attend high schools with fewer resources. The study provided some support for this hypothesis and showed that the prediction of college grades can be improved using information about high school socioeconomic status. An interesting peripheral finding was that grades provided by students’ high schools were stronger predictors of FGPA than were students’ self‐reported high school grades. Correlations between the two types of high school grades (computed for each of 18 colleges) ranged from .59 to .85.