Rejoinder: Matched Pairs and the Future of Cluster-Randomized Experiments

Rejoinder to "The Essential Role of Pair Matching in Cluster-Randomized Experiments, with Application to the Mexican Universal Health Insurance Evaluation" [arXiv:0910.3752]Comment: Published in at http://dx.doi.org/10.1214/09-STS274REJ the Statistical Science (http://www.imstat.org/sts/) by the Institute of Mathematical Statistics (http://www.imstat.org

O Week and Week One of Classes at Otago!

Postcard from Rebecca Nall, during the Linfield College Semester Abroad Program at the University of Otago in Dunedin, New Zealan

Uppers and Downers: Understanding Sleep Regulation Using Small Molecules in Drosophila

Sleep is an important physiological state, but its function and regulation remain elusive. In Drosophila melanogaster, a useful model organism for studying sleep, forward genetic screens have identified important sleep-modulating genes and pathways; however, the results of such screens may be limited by developmental abnormalities or lethality associated with mutation of certain genes. To circumvent these limitations, we screened 1280 small molecules for effects on sleep in adult Drosophila. We used genetic and molecular approaches to elucidate the mechanisms by which two of these drugs altered sleep behavior. We found that administration of reserpine, a small molecule inhibitor of the vesicular monoamine transporter (VMAT) that repackages monoamines into presynaptic vesicles, resulted in an increase in sleep. We found that VMAT-null mutants, like reserpine-fed flies, have an increased sleep phenotype, as well as an increased arousal threshold and resistance to the effects of reserpine. However, although the VMAT mutants are consistently resistant to reserpine, other aspects of their sleep phenotype are dependent on genetic background. Thus, they may not have been detected in a classical forward genetic screen, further attesting to the utility of a small molecule screen. Mutations affecting single monoamine pathways did not affect reserpine sensitivity, suggesting that effects of VMAT/reserpine on sleep are mediated by multiple monoamines. We also studied the mode of action of caffeine, a common wake-promoting compound. Caffeine is thought to promote wake by inhibiting adenosine receptors, however previous work demonstrated that the wake-promoting effects of caffeine are independent of the adenosine receptor in the fly. We show that dopamine is required for the wake-promoting effect of caffeine in the fly, and that caffeine likely acts presynaptically to increase dopamine signaling. We identify a cluster of neurons, the paired anterior medial (PAM) cluster of dopaminergic neurons, which are essential for the caffeine response and which show increased activity following caffeine administration. Overall, we find that small molecule screens can be used effectively to identify regulators of adult behavior. The results of our screen and follow-up experiments demonstrate that presynaptic modulation of monoamine signaling may be a major source of sleep regulation

Microorganisms in solid materials. phases i, ii, iii, and iv final summary report

Culturing techniques for detection of viable microorganism inoculated into solid material

Markets and Prospects for African Exports of Fruits and Vegetables to European Countries

Structural adjustment programs and an increasing debt burden have put pressure on African countries to increase their export earnings. This has led to increased interest in nontraditional and high-value exports, such as fresh and preserved fruits and vegetables. Markets for offseason fruits and vegetables, and for tropical fruits, seem to be expanding. Nevertheless, African producers are faced with increasing competition. This paper summarizes the major trends in the principal markets for African horticultural exports, and discusses the likely impact of increased competition and changes in trading structures. Market liberalization within the EU, and the expansion of Union membership, threaten traditional trading relations between its members and African producers of fruits and vegetables. Increased investment in fruit and vegetable production in the European Union and elsewhere are likely to further increase the level of competition. For countries with existing export industries, the appropriate strategy would probably involve investments in improved efficiency, such as improvements in the infrastructure for bringing products to the point of embarkation and for storing them prior to shipment. Countries trying to develop new export products must try to identify niche markets which they can address, based on climate, seasonality or cost factors

Robotics in the classroom: The effectiveness of robotics based curriculum in STEM education

Students learn best when they are engaged and are able to interact with their environment. They can build their own definition of concepts and themes, which are more meaningful because they are related to their own experiences and memories (Kolb, 1984). Simply put it all comes down to constructivism, which means a person builds knowledge and meaning from interactions between their experiences and ideas (the environment they work/play in and the people and objects they interact with). The purpose of this study is to find out how a middle school and high school constructivist robotics curriculum impacts students’ conceptual understanding of electrical circuit concepts

Supporting Social and Emotional Learning in the EFL/ESL Classroom: How the New Science of Child Development Can Inform Second Language Acquisition Theory and Practice

Research in the field of Second Language Acquisition (SLA) generally falls within two categories: the cognitive/psycholinguistic camp, and the sociocultural camp (Fazel, 2014). These distinct approaches to empirical research in SLA have diverse epistemologies, methods, and implications for the second language classroom. Scholars within the sociocultural camp have made significant contributions to the field concerning social and emotional learning in the second language classroom. Concerning this, the current paper reviews recent developments in the field of developmental psychology and examines ways in which the new science of child development can inform SLA theory and practice in regard to social and emotional learning in the second language classroom. This paper reviews the two most common approaches to parenting that are recognized by developmental psychologists (Gopnik, 2016) and relates those conceptualizations to teaching in the second language classroom. Going further, developmental psychologists have identified four distinct types of play, and have investigated each in terms of how they contribute to the social and emotional development of children and adolescents (Gopnik, 2016). Based on this discussion the current author considers the importance of play with a second language (i.e. experimentation with learned language items through the social and emotional process of constructivist interaction) and its role in social and emotional development in the second language learning context. Finally, the author ends by making the case for the second language apprenticeship based on revelations both from the field of developmental psychology, and second language acquisition. The new science of child development can inform SLA theory and practice by providing a broader framework supported by ample empirical evidence from which to view and understand social and emotional learning in the second language classroom