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Large-scale international databases provide valuable resources for scholars, educators and policy-makers interested in civic engagement and education in nations that are democracies or striving towards democracy. However, the multidisciplinary nature of secondary analysis of these data has created a fragmentary picture that limits educators’ awareness of relevant findings. We present a summary of research conducted across disciplines using datasets from two large-scale cross-national studies of civic education conducted by the International Association for the Evaluation of Educational Achievement (CIVED:99 and ICCS:09). The IEA studies were conducted in more than 40 countries with nationally representative samples of 14–15 year olds. In a review of over 100 published articles reporting secondary analyses of these data, we identified four themes especially salient for citizenship educators: open classroom climates; teaching and learning approaches; student identity; and profiles of citizenship norms and attitudes. The review summarizes sample relevant articles to illustrate themes, emphasizes connections between education and civic engagement and suggests opportunities for future research.

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Haloalkane dehalogenases have the potential for use in high‐value biocatalytic processes to convert haloalkanes into epoxides via intermediate haloalcohols. Initial bioreactor studies probing the hydrolysis of 1,2,3‐trichloropropane by immobilized wild‐type dehalogenase isolated from Rhodococcus rhodochrous demonstrated, however, that productivity was too low to realize a commercially viable process. A strategy to increase enzyme performance was undertaken to increase the reaction temperature, however it was determined that the wild‐type enzyme was not stable for long periods of time at elevated temperatures. The accelerated laboratory evolution technique of Gene Site Saturation Mutagenesis (GSSM TM) was used to create a clonal enzyme library comprising all single site sequence variants of the Rhodococcus enzyme. Using high throughput screening techniques and rapid kinetics assays, this library was probed for improvements in thermostability and for the ability of the enzyme to undergo a fully reversible cycle of thermal denaturation‐renaturation. Eight single site mutants were discovered that had considerable effects on these aspects of the dehalogenase phenotype. Compared to the parental dehalogenase (t1/2 = 11 minutes at 55 °C) single site variants have half‐lives ranging from 300 minutes to 2700 minutes. Combinations of these mutations dramatically improved the half‐life demonstrating the enhancing effects of mutational additivity. Combining five of the mutations into a single protein (Dhla5) improved the half‐life to 29,000 min and a combination of all eight single‐site mutations (Dhla8) increased the half‐life by another factor of ten. Thus, the final Dhla8 protein was 30,000 times more stable than the parent molecule as measured by its ability to refold after denaturation at high temperature. Kinetic analysis showed that the improvement in thermal stability associated with Dhla5 did not negatively affect the rate of catalysis at ambient temperature, and allowed a significant increase in rate with no deactivation at 55 °C. Differential scanning calorimetry demonstrated that mutational combinations in both Dhla5 and Dhla8 led to an 8 °C increase in Tm and substantiated that partial reversibility (Dhla5) and full reversibility of Dhla8. Thermal denaturation of Dhla8 was fully reversible upon scanning up to 90 °C. Bioreactor studies showed that improved thermal stability of Dhla5 and Dhla8 correlated qualitatively with increased productivity when haloalkane hydrolysis was conducted using immobilized forms of these evolved enzymes under high temperature conditions.

Haloalkane dehalogenases have the potential for use in high-value biocatalytic processes to convert haloalkanes into epoxides via intermediate haloalcohols. Initial bioreactor studies probing the hydrolysis of 1,2,3-trichloropropane by immobilized wild-type dehalogenase isolated from Rhodococcus rhodochrous demonstrated, however, that productivity was too low to realize a commercially viable process. A strategy to increase enzyme performance was undertaken to increase the reaction temperature, however it was determined that the wild-type enzyme was not stable for long periods of time at elevated temperatures. The accelerated laboratory evolution technique of Gene Site Saturation Mutagenesis (GSSM TM ) was used to create a clonal enzyme library comprising all single site sequence variants of the Rhodococcus enzyme. Using high throughput screening techniques and rapid kinetics assays, this library was probed for improvements in thermostability and for the ability of the enzyme to undergo a fully reversible cycle of thermal denaturation-renaturation. Eight single site mutants were discovered that had considerable effects on these aspects of the dehalogenase phenotype. Compared to the parental dehalogenase (t 1/2 = 11 minutes at 55°C) single site variants have half-lives ranging from 300 minutes to 2700 minutes. Combinations of these mutations dramatically improved the half-life demonstrating the enhancing effects of mutational additivity. Combining five of the mutations into a single protein (Dhla5) improved the half-life to 29,000 min and a combination of all eight single-site mutations (Dhla8) increased the half-life by another factor of ten. Thus, the final Dhla8 protein was 30,000 times more stable than the parent molecule as measured by its ability to refold after denaturation at high temperature. Kinetic analysis showed that the improvement in thermal stability associated with Dhla5 did not negatively affect the rate of catalysis at ambient temperature, and allowed a significant increase in rate with no deactivation at 55°C. Differential scanning calorimetry demonstrated that mutational combinations in both Dhla5 and Dhla8 led to an 8°C increase in T m and substantiated that partial reversibility (Dhla5) and full reversibility of Dhla8. Thermal denaturation of Dhla8 was fully reversible upon scanning up to 90°C. Bioreactor studies showed that improved thermal stability of Dhla5 and Dhla8 correlated qualitatively with increased productivity when haloalkane hydrolysis was conducted using immobilized forms of these evolved enzymes under high temperature conditions.

Using data from the International Civic and Citizenship Study, this quantitative study explores the potential for open classroom climates to foster political efficacy and civic knowledge among 8th grade students in 14 Western European countries. Findings show that an open classroom climate is associated with increased civic knowledge and political efficacy. In addition, civic knowledge and political efficacy are positively correlated with social movement citizenship. However, the relationships between both political efficacy and civic knowledge on social movement citizenship are strengthened with presence of an open classroom climate. This study demonstrates the importance of an open classroom climate to develop students’ knowledge and efficacy related to active citizenship.

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