A pilot scale trickling filter with pebble gravel as media and its performance to remove chemical oxygen demand from synthetic brewery wastewater

Evaluating the performance of a biotrickling filter for the treatment of wastewaters produced by a company manufacturing beer was the aim of this study. A pilot scale trickling filter filled with gravel was used as the experimental biofilter. Pilot scale plant experiments were made to evaluate the performance of the trickling filter aerobic and anaerobic biofilm systems for removal of chemical oxygen demand (COD) and nutrients from synthetic brewery wastewater. Performance evaluation data of the trickling filter were generated under different experimental conditions. The trickling filter had an average efficiency of (86.81±6.95)% as the hydraulic loading rate increased from 4.0 to 6.4 m³/(m²·d). Various COD concentrations were used to adjust organic loading rates from 1.5 to 4.5 kg COD/(m³·d). An average COD removal efficiency of (85.10±6.40)% was achieved in all wastewater concentrations at a hydraulic loading of 6.4 m³/(m²·d). The results lead to a design organic load of 1.5 kg COD/(m³·d) to reach an effluent COD in the range of 50–120 mg/L. As can be concluded from the results of this study, organic substances in brewery wastewater can be handled in a cost-effective and environmentally friendly manner using the gravel-filled trickling filter.     

Making learning whole: an instructional approach for mediating the practices of authentic science inquiries

This design experiment aimed to answer the question of how to mediate the practices of authentic science inquiries in primary education. An instructional approach based on activity theory was designed and carried out with multi-age students in a small village school. An open-ended learning task was offered to the older students. Their task was to design and implement instruction about the Ice Age to their younger fellows. The objective was collaborative learning among students, the teacher, and outside domain experts. Mobile phones and GPS technologies were applied as the main technological mediators in the learning process. Technology provided an opportunity to expand the learning environment outside the classroom, including the natural environment. Empirically, the goal was to answer the following questions: What kind of learning project emerged? How did the students’ knowledge develop? What kinds of science learning processes, activities, and practices were represented? Multiple and parallel data were collected to achieve this aim. The data analysis revealed that the learning project both challenged the students to develop explanations for the phenomena and generated high quality conceptual and physical models in question. During the learning project, the roles of the community members were shaped, mixed, and integrated. The teacher also repeatedly evaluated and adjusted her behavior. The confidence of the learners in their abilities raised the quality of their learning outcomes. The findings showed that this instructional approach can not only mediate the kind of authentic practices that scientists apply but also make learning more holistic than it has been. Thus, it can be concluded that nature of the task, the tool-integrated collaborative inquiries in the natural environment, and the multiage setting can make learning whole.     

Strategies for Selling Paid Content on Newspaper and Magazine Web Sites: An Empirical Analysis of Bundling and Splitting of News and Magazine Articles

More and more newspaper and magazine Web sites offer paid content. However, selling information goods at a price higher than the marginal cost means finding a strategy for product or price differentiation. A possible strategy to solve this problem is the bundling of information goods. In this article, we analyze empirically, with quantitative statistic methods, strategies for selling bundled and unbundled content on newspaper and magazine Web sites. This analysis is based on the theoretical approach of Bakos and Brynjolfsson (1996). The article shows that a cannibalization takes place if the same bundle of information goods is offered in offline (printed) and online (digital) media at the same time. Traditional bundling models work nonetheless in an online media if the online content is rebundled (e.g., as dossiers about a topic), but thereby do not compete with the printed version.     

Tocqueville on democracy and inclusive education: a more ardent and enduring love of equality than of liberty

Drawing from some of the insights on the democratic condition made by Alexis de Tocqueville, this article examines critically the reasons given for inclusive education and the motives behind its growing popularity in western industrialised countries. In particular, we consider the supposed benefits of democratisation and equality that proponents of inclusive schooling usually claim. After summarising the benefits that advocates of inclusive education have articulated, we give a brief sketch of Tocqueville’s analysis of democratic societies. His observations have demonstrated that democratisation and equality are not necessarily healthy impulses in a democratic society because they have the propensity to smother individual freedom and dissent from commonly held opinions. Accordingly, we argue that the very claims of democratisation and equality are inherently problematic and are potentially inimical to individuals’ ability to judge independently. In other words, we argue that democratisation and equality are not necessarily compatible with liberty. We conclude, then, that an educational system that does not prioritise and protect intellectual development for sake of inclusion can only exacerbate these deleterious democratic tendencies. We also assert that inclusive policies reflect the relentless pursuit of equality that democratic peoples exhibit to their own disadvantage.     

Searching for pedagogical adaptations by exploring teacher’s tacit knowledge and interactional co-regulation in the education of pupils with autism

The purpose of this article is to introduce a research design, which aims to find useful pedagogical adaptations for teaching pupils with autism. Autism is a behavioural syndrome characterised by disabilities and dysfunctions in interaction and communication, which is why it is interesting to explore educational processes particularly from an interactional perspective in a class with pupils with autism. The main focus is in exploring teacher’s tacit knowledge and interactional co-regulation between the teacher and the pupils. This study is a part of a larger Finnish project, which involves the education of pupils with autism in the primary school system. In the study described, six video recordings (each about 30?min) were taken under analysis due to the uniqueness in the research context of special education: the videos are rare in that they involve only the teacher and her six pupils with autism; no helpers are present in the classroom. This study explored the phenomenon ethnomethodologically. This study indicated that it is possible to apply a general theory of interaction when exploring people with autism, although the main diagnostic criteria of autism are disabilities in social interaction and communication. It was possible to extract episodes from the behaviour of the teacher that showed her tacit knowledge becoming concrete. These results could be taken into consideration when planning and carrying out teaching in different contexts and in teacher education, too.     

Making inquiry-based science learning visible: the influence of CVS and cognitive skills on content knowledge learning in guided inquiry

ABSTRACT

Many science curricula and standards emphasise that students should learn both scientific knowledge and the skills associated with the construction of this knowledge. One way to achieve this goal is to use inquiry-learning activities that embed the use of science process skills. We investigated the influence of scientific reasoning skills (i.e. conceptual and procedural knowledge of the control-of-variables strategy) on students’ conceptual learning gains in physics during an inquiry-learning activity. Eighth graders (n?=?189) answered research questions about variables that influence the force of electromagnets and the brightness of light bulbs by designing, running, and interpreting experiments. We measured knowledge of electricity and electromagnets, scientific reasoning skills, and cognitive skills (analogical reasoning and reading ability). Using structural equation modelling we found no direct effects of cognitive skills on students’ content knowledge learning gains; however, there were direct effects of scientific reasoning skills on content knowledge learning gains. Our results show that cognitive skills are not sufficient; students require specific scientific reasoning skills to learn science content from inquiry activities. Furthermore, our findings illustrate that what students learn during guided inquiry activities becomes visible when we examine both the skills used during inquiry learning and the process of knowledge construction. The implications of these findings for science teaching and research are discussed.     

Climate Change and Morality: Students' perspectives on the individual and society

There is a growing interest in addressing moral aspects in the research and education of socio‐scientific issues. This paper investigates students' interpretations of climate change from a moral perspective. The students were 14 years old, studying at Green Schools in the Beijing area, China. The study was based on semi‐structured group interviews and the data were analysed from an intentional perspective, which means that both cognitive and situational aspects were taken into consideration in the analysis. Previous research has revealed a close relation between morality and socio‐scientific issues and also advocated the need for addressing ethical aspects in science education. However, empirical studies exploring the question of what students' moral reasoning might look like at the individual level have not yet generated enough attention. In this study this is the core focus of interest. The findings show that the students conceptualise the solutions to mitigating climate change in relation to two different stances. That is, they contextualise the problems and solutions by addressing the individual, where the individual is either ‘myself’ or ‘someone else’. The different notions of the individual become crucial as the students' views and considerations for the environment, as well as society, change according to the different contexts. From a moral point of view, the students seem quite unaware of their varying consideration for others, the environment and society. The paper ends with a discussion of implications for practice and research.     

Contextualizing Teacher Autonomy in time and space: a model for comparing various forms of governing the teaching profession

This study aims to develop a model for comparing different forms of teacher autonomy in various national contexts and at different times. Understanding and explaining local differences and global similarities in the teaching profession in a globalized world require conceptions that contribute to further theorization of comparative and international education. Drawing on a governance perspective and building on considerations of curriculum evaluation, the study argues that teacher autonomy is a crucial factor that has to be conceptualized in its national and historical contexts. It presents an examination of the teaching profession from both an institutional and service perspective. In both perspectives, teacher autonomy, framed by curriculum evaluation, can be regarded as both extended and restricted, but not necessarily at the same time. This point of view enables us to discuss different forms of autonomy in relation to each other. To support this idea, the study discusses cases of teachers in various contexts of time and space.     

Being Labeled Nerd: Factors That Influence the Social Acceptance of High-Achieving Students

The present investigation addresses the question of whether certain factors can protect high-achieving students at risk for being labeled a nerd against devaluation. In 2 studies, 125 and 317 students from Grade 8 evaluated vignettes describing average students and students who were called “nerds.” Results indicate that being modest about good grades, being engaged in sports, and being sociable led to higher liking. In students who were labeled nerds, but not in average students, display of effort led to less favorable evaluations. The effects of the aforementioned factors were moderated by the gender of the perceivers and targets. Findings are discussed with respect to gender-role stereotypes and the self presentation of high-achieving students.