Genetic and environmental influences on prereading skills and early reading and spelling development in the United States, Australia, and Scandinavia

Genetic and environmental influences on prereading skills in preschool and on early reading and spelling development at the end of kindergarten were compared among samples of identical and fraternal twins from the U.S. (Colorado), Australia, and Scandinavia. Mean comparisons revealed significantly lower preschool print knowledge in Scandinavia, consistent with the relatively lower amount of shared book reading and letter-based activities with parents, and lack of emphasis on print knowledge in Scandinavian preschools. The patterns of correlations between all preschool environment measures and prereading skills within the samples were remarkably similar, as were the patterns of genetic, shared environment, and non-shared environment estimates: in all samples, genetic influence was substantial and shared environment influence was relatively weak for phonological awareness, rapid naming, and verbal memory; genetic influence was weak, and shared environment influence was relatively strong for vocabulary and print knowledge. In contrast, for reading and spelling assessed at the end of kindergarten in the Australian and U.S. samples, there was some preliminary evidence for country differences in the magnitude of genetic and environmental influences. We argue that the apparently higher genetic and lower shared environment influence in the Australian sample was related to a greater emphasis on formal reading instruction, resulting in more advanced reading and spelling skills at the end of kindergarten, and thus there was greater opportunity to observe genetic influences on response to systematic reading instruction among the Australian twins.     

The engineering of engineering education: curriculum development from a designer's point of view

Engineers have a set of powerful tools at their disposal for designing robust and reliable technical systems. In educational design these tools are seldom applied. This paper explores the application of concepts from the systems approach in an educational context. The paradigms of design methodology and systems engineering appear to be suitable for both analysing existing education and designing new curricula.     

Processes of problem solving: Comparison of an American and a European view

Analysis of the ability to solve problems occupies an important place in recent research within instructional psychology. In the U.S.A. processes of problem solving are now mostly studied within the framework of the information-processing approach. A European trend in research on thinking and problem solving, that parallels this American work, is based on the action-oriented approach. Until now both approaches have developed independently. A consequence of this situation could be that differences between both conceptions will be accentuated, while points of convergence remain hidden. Therefore it seems desirable to start an exchange of ideas between the two approaches. The present article provides an example in this direction. The example relates to the work of Resnick and Glaser on problem solving in instructional settings on the one hand, and a view developed in the Netherlands during the 70s on the other.Paper presented at a seminar at the University of Pittsburgh, Learning Research and Development Center, March 1979.     

Mentoring as a learning tool: enhancing the effectiveness of an undergraduate business mentoring program

Mentoring can be used as a pedagogical alternative both to extend and augment the educational experience of business students. This article addresses a gap in the literature regarding the use and effectiveness of mentoring in undergraduate business education by examining improvements to an existing mentoring program. After reviewing the mentoring literature and identifying four critical elements for program success (matching, preparation, interaction and outcome assessment), the researchers used a cohort design and developed a survey to assess baseline participant satisfaction with these elements. Interventions were developed to enhance the mentoring program, and a second cohort allowed the authors to assess the benefits of these interventions. With statistically significant improvements in two out of four program elements (and a third showing marginally significant differences), the results demonstrate that the authors’ approach to evaluating and enhancing mentoring program effectiveness is useful in business education.     

Implications of Stealing Thunder for the Impact of Expressing Emotions in Organizational Crisis Communication

This study examines if and when spokespersons of an organization in crisis can express their genuine emotions as opposed to appearing rational. The impact of emotional (sadness) versus rational message framing on perceptions of an organization in crisis is studied by means of a 2 (crisis timing strategy: ex-antecrisis timing strategy vs. ex-postcrisis timing strategy)×2 (message framing: rational vs. emotional) between-subjects factorial experimental design with 168 participants. The findings first show that organizations can restore their reputation in times of crisis better by means of an ex-antecrisis timing strategy than by means of an ex-postcrisis timing strategy. In addition, the study illustrates that an ex-antecrisis timing strategy leads to more effective use of organizational message framing. In the case of an organizational self-disclosure, expressing sadness as a discrete negative emotion results in a better postcrisis reputation than rational message framing, whereas no impact of message framing is found for an ex-postcrisis timing strategy. Finally, the results indicate that organizations can benefit from allowing their spokespersons to express sadness because consumers will consider them more sincere.     

Second Generation Net News: Interactivity and Information Accessibility in the Online Environment

This study assesses the ways in which local television news operations and major metropolitan newspapers in the top 40 U.S. media markets are making information accessible and structuring interactive experiences online as the industry transitions into a third generation of Internet news. As Net news approaches its first decade of existence, online news sites are assumed to be evolving from a noninteractive, passive model of information delivery into an environment of increased immediacy, content richness, and user control. To investigate this question, a content analysis was performed in 2 waves, once during fall 1998 and again during fall 2000. For comparative purposes, differences across years are examined. In addition, the efforts of local television news sites are contrasted with the online activities of dominant newspaper sites, which have assumed a commanding lead in building a local online audience. The analysis argues for valuing Net news sites less from a profit-loss standpoint and more for the nonmonetary contributions they make in relation to the broader news mission, namely, enhanced coverage, brand loyalty, and news credibility.     

Aprender en la escuela con las nuevas tecnologías de la información: Perspectivas desde la psicología del aprendizaje y de la instrucción

La transferencia entre el dominio de la investigación básica y el de la práctica educativa no siempre se da, y cuando eso ocurre, hay un cierto riesgo de que la transferencia viaje en una sola dirección. En este artículo se analiza el estado de la cuestión respecto a las enormes posibilidades que para el mundo educativo abre la investigación en psicología cognitiva y, más concretamente, la investigación sobre la utilización del ordenador como instrumento de enseñanza-aprendizaje.     

MIFGASHIM: A Meeting of Minds and Hearts

“Mifgashim” — structured meetings between Diaspora participants of Israel Experience Programs and Israeli youth — are organized to strengthen ties between the two populations. Two basic models of Mifgashim are offered, one emphasizing cognitive and the other affective means of achieving the same goal. The cognitive‐based model had a slightly stronger impact, especially on the Israeli participants. Nonetheless, both fall somewhat short of their potential in impact and satisfaction. We believe that the types of activities within the Mifgashim programs are not the source of the encounter's shortfalls. Rather, the difficulties include the brief time allotted, language barriers, and group functioning, in particular adolescent group dynamics. Perhaps the most fundamental problem is a widespread perception that the Mifgashim are conducted primarily for the benefit of the Diaspora youth. The objectification of the Israeli participants by program planners can be seen as reflecting attitudes in the larger field of Israel‐American relations.     

Rogge’s Games: Establishing the Youth Olympic Games as a New Event in the Olympic Movement

Abstract

The Youth Olympic Games (YOG) were established as a new event in the Olympic family at a session of the International Olympic Committee (IOC) in July 2007. This paper illuminates why and how this new event was established. It turns out that the formally unanimous decision to establish the event was taken in a contested terrain. Much attention has been put on the agency of the then president of the IOC, Jacques Rogge, and his role as an institutional leader is discussed in a context where the pressure of tradition is strong. Securing the character of an organization which has become an institution is a central task for institutional leadership, and developing an ‘external mechanism’ or a new subfield like the YOG is a way to explore this. Appealing to original ideas and values, such as the educational role of the games, is of importance but would in itself not be enough to convince the fellow members of the IOC’s decision-making bodies. Acting politically as a ‘statesman’ with the skills and ability to manoeuvre among different interests and wills was equally a necessity to convince the decision makers to welcome this new event into the Olympic movement.     

Polyphosphonium‐based bipolar membranes for rectification of ionic currents

Bipolar membranes (BMs) have interesting applications within the field of bioelectronics, as they may be used to create non-linear ionic components (e.g., ion diodes and transistors), thereby extending the functionality of, otherwise linear, electrophoretic drug delivery devices. However, BM based diodes suffer from a number of limitations, such as narrow voltage operation range and/or high hysteresis. In this work, we circumvent these problems by using a novel polyphosphonium-based BM, which is shown to exhibit improved diode characteristics. We believe that this new type of BM diode will be useful for creating complex addressable ionic circuits for delivery of charged biomolecules.Combined electronic and ionic conduction makes organic electronic materials well suited for bioelectronics applications as a technological mean of translating electronic addressing signals into delivery of chemicals and ions.¹ For complex regulation of functions in cells and tissues, a chemical circuit technology is necessary in order to generate complex and dynamic signal gradients with high spatiotemporal resolution. One approach to achieve a chemical circuit technology is to use bipolar membranes (BMs), which can be used to create the ionic equivalents of diodes^{2, 3, 4, 5} and transistors.^{6, 7, 8} A BM consists of a stack of a cation- and an anion-selective membrane, and functions similar to the semiconductor PN-junction, i.e., it offers ionic current rectification^{9, 10} (Figure ​(Figure1a).1a). The high fixed charge concentration in a BM configuration make them more suited in bioelectronic applications as compared to other non-linear ionic devices, such as diodes constructed from surface charged nanopores¹¹ or nanochannels,¹² as the latter devices typically suffers from reduced performance at elevated electrolyte concentration (i.e., at physiological conditions) due to reduced Debye screening length.¹³ However, a unique property of most BMs, as compared to the electronic PN-junction and other ionic diodes, is the electric field enhanced (EFE) water dissociation effect.^{10, 14} This occurs above a threshold reverse bias voltage, typically around −1 V, as the high electric field across the ion-depleted BM interface accelerates the forward reaction rate of the dissociation of water into H⁺ and OH⁻ ions. As these ions migrate out from the BM, there will be an increase in the reverse bias current. The EFE water dissociation is a very interesting effect and is commonly used in industrial electrodialysis applications,¹⁵ where highly efficient water dissociating BMs are being researched.¹⁶ Also, BMs have also been utilized to generate H⁺ and OH⁻ ions in lab-on-a-chip applications.^{2, 17} However, the EFE water dissociation effect diminishes the diode property of BMs when operated outside the ±1 V window, which is unwanted in, for instance, chemical circuits and addressing matrices for delivery of complex gradients of chemical species. The effect can be suppressed by incorporating a neutral electrolyte inside the BM,^{10, 18} for instance, poly(ethylene glycol) (PEG).^{2, 6, 7} However, as previously reported,² the PEG volume will introduce hysteresis when switching from forward to reverse bias, due to its ability to store large amounts of charges. This was circumvented by ensuring that only H⁺ and OH⁻ are present in the diode, which recombines into water within the PEG volume. Such diodes are well suited as integrated components in chemical circuits for pH-regulation, due to the in situ formed H⁺ and OH⁻, but are less attractive if, for instance, other ions, e.g., biomolecules, are to be processed or delivered in and from the circuit. Furthermore, a PEG electrolyte introduces additional patterning layers, making device downscaling more challenging. This is undesired when designing complex, miniaturized, and large-scale ionic circuits. Thus, there is an interest in BM diodes that intrinsically do not exhibit any EFE water dissociation, are easy to miniaturize, and that turn off at relatively high speeds. It has been suggested that tertiary amines in the BM interface are important for efficient EFE water dissociation,^{19, 20, 21} as they function as a weak base and can therefore catalyze dissociation of water by accepting a proton. For example, anion-selective membranes that have undergone complete methylation, converting all tertiary amines to quaternary amines, shows no EFE water dissociation,¹⁹ although this effect was not permanent, as the quaternization was reversed upon application of a current. Similar results were found for anion-selective membranes containing alkali-metal complexing crown ethers as fixed charges.²¹ Also, EFE water dissociation was not observed or reduced in BMs with poor ion selectivity, for example, in BMs with low fixed-charge concentration⁵ or with predominantly secondary and tertiary amines in the anion-selective membrane,²² as the increased co-ion transport reduces the electric field at the BM interface. However, due to decreased ion selectivity, these membranes show reduced rectification. In this work, we present a non-amine based BM diode that avoids EFE water dissociation, enables easy miniaturization, and provides fast turn-off speeds and high rectification.Open in a separate windowFigure 1(a) Ionic current rectification in a BM. In forward bias, mobile ions migrate towards the interface of the BM. The changing ion selectivity causes ion accumulation, resulting in high ion concentration and high conductivity. At high ion concentration, the selectivity of the membranes fails (Donnan exclusion failure), and ions start to pass the BM. In reverse bias, the mobile ions migrate away from the BM, eventually giving a zone with low ion concentration and low conductivity. Reverse bias can cause EFE water dissociation, producing H⁺ and OH^- ions. (b) Chemical structures of PSS, qPVBC, and PVBPPh₃. (c) The device used to characterize the BMs and the BM1A, BM2A, and BM1P designs. The BM interfaces are 50 × 50 μm.An anion-selective phosphonium-based polycation (poly(vinylbenzyl chloride) (PVBC) quaternized by triphenylphospine, PVBPPh₃) was synthesized and compared to the ammonium-based polycation (PVBC quaternized by dimethylbenzylamine, qPVBC) previously used in BM diodes² and transistors,^{7, 8} when included in BM diode structures together with polystyrenesulfonate (PSS) as the cation-selective material (Figure ​(Figure1b).1b). Three types of BM diodes were fabricated using standard photolithography patterning (Figure ​(Figure1c),1c), either with qPVBC (BM1A and BM2A) or PVBPPh₃ (BM1P) as polycation and either with (BM2A) or without PEG (BM1A and BM1P). Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) electrodes covered with aqueous electrolytes were used to convert electronic input signals into ionic currents through the BMs, according to the redox reaction PEDOT⁺:PSS⁻ + M⁺ + e⁻ ↔ PEDOT⁰ + M⁺:PSS⁻.The rectifying behavior of the diodes was evaluated using linear sweep voltammetry (Figure ​(Figure2).2). The BM1A diode exhibited an increase in the reverse bias current for voltages lower than −1 V, a typical signature of EFE water dissociation,^{10, 14} which decreased the current rectification at ±4 V to 6.14. No such deviation in the reverse bias current was observed for BM2A and BM1P, which showed rectification ratios of 751 and 196, respectively. In fact, for BM1P, no evident EFE water dissociation was observed even at −40 V (see inset of Figure ​Figure2).2). Thus, the PVBPPh₃ polycation allows BM diodes to operate at voltages beyond the ±1 V window with maintained high ion current rectification.Open in a separate windowFigure 2Linear sweep voltammetry from −4 to +4 V (25 mV/s) for the BM diodes. The inset shows BM1P scanning from −40 V to +4 V (250 mV/s).The dynamic performance of the diodes was tested by applying a square wave pulse from reverse bias to a forward bias voltage of 4 V with 5–90 s pulse duration (Figure ​(Figure3).3). To access the amount of charge injected and extracted during the forward bias and subsequent turn off, the current through the device was integrated. For BM2A, we observed that the fall time increased with the duration of the forward bias pulse. This hysteresis is due to the efficient storage of ions in the large PEG volume, with no ions crossing the BM due to Donnan exclusion failure.² As a result, during the initial period of the return to reverse bias, a large amount of charge needs to be extracted in order to deplete the BM. After a 90 s pulse, 90.6% of the injected charge during the forward bias was extracted before turn-off. This may be contrasted with BM1P, where the fall time is hardly affected by the pulse duration, and the extracted/injected ratio is only 15.4% for a 90 s pulse. For this type of BM, the interface quickly becomes saturated with ions during forward bias, leading to Donnan exclusion failure and transport of ions across the BM.⁴ Thus, less charge needs to be extracted to deplete the BM, allowing for faster fall times and significantly reduced hysteresis.Open in a separate windowFigure 3Switching characteristics (5, 10, 20, 30, 60, or 90 s pulse) and ion accumulation (at 90 s pulse) of the BM2A and BM1P diodes. BM1A showed similar characteristics as BM1P when switched at ±1V (see supplementary material).²⁴Since the neutral electrolyte is no longer required to obtain high ion current rectification over a wide potential range, the size of the BM can be miniaturized. This translates into higher component density when integrating the BM diode into ionic/chemical circuits. A miniaturized BM1P diode was constructed, where the interface of the BM was shrunk from 50 μm to 10 μm. The 10 μm device showed similar IV and switching characteristics as before (Figure ​(Figure4),4), but with higher ion current rectification ratio (over 800) and decreased rise/fall times (corresponding to 90%/–10% of forward bias steady state) from 10 s/12.5 s to 4 s/4 s. Since the overlap area is smaller, a probable reason for the faster switching times is the reduced amount of ions needed to saturate and deplete the BM interface. In comparison to our previous reported low hysteresis BM diode,² this miniaturized polyphosphonium-based devices shows the same rise and fall times but increased rectification ratio.Open in a separate windowFigure 4(a) Linear sweep voltammetry and (b) switching performance of a BM1P diode with narrow junction.In summary, by using polyphosphonium instead of polyammonium as the polycation in BM ion diodes the EFE water dissociation can be entirely suppressed over a large operational voltage window, supporting the theory that a weak base, such as a tertiary amine, is needed for efficient EFE water dissociation.^{17, 18} As no additional neutral layer at the BM interface is needed, ion diodes that operate outside the usual EFE water dissociation window of ±1 V can be constructed using less active layers, fewer processing steps and with relaxed alignment requirement as compared to polyammonium-based devices. This enables the fabrication of ion rectification devices with an active interface as low as 10 μm. Furthermore, the exclusion of a neutral layer improves the overall dynamic performance of the BM ion diode significantly, as there is less hysteresis due to ion accumulation. Previously, the hysteresis of BM ion diodes has been mitigated by designing the diode so that only H⁺ and OH⁻ enters the BM, which then recombines into water.² Such diodes also show high ion current rectification ratio and switching speed but are more complex to manufacture, and their application in organic bioelectronic systems is limited due to the H⁺/OH⁻ production. By instead using the polyphosphonium-based BM diode, reported here, we foresee ionic, complex, and miniaturized circuits that can include charged biomolecules as the signal carrier to regulate functions and the physiology in cell systems, such as in biomolecule and drug delivery applications, and also in lab-on-a-chip applications.