Exploring Mechanisms of Bacterial Adaptation to Seasonal Temperature Change

This research examines three potential mechanisms by which bacteria can adapt to different temperatures: changes in strain-level population structure, gene regulation and particle colonization. For the first two mechanisms, I utilize bacterial strains from the Vibrionaceae family due to their ease of culturability, ubiquity in coastal environments and status as a model system for marine bacteria. I first examine vibrio seasonal dynamics in temperate, coastal water and compare the thermal performance of strains that occupy different thermal environments. Our results suggest that there are tradeoffs in adaptation to specific temperatures and that thermal specialization can occur at a very fine phylogenetic scale. The observed thermal specialization over relatively short evolutionary time-scales indicates that few genes or cellular processes may limit expansion to a different thermal niche. I then compare the genomic and transcriptional changes associated with thermal adaptation in closely-related vibrio strains under heat and cold stress. The two vibrio strains have very similar genomes and overall exhibit similar transcriptional profiles in response to temperature stress but their temperature preferences are determined by differential transcriptional responses in shared genes as well as temperature-dependent regulation of unique genes. Finally, I investigate the temporal dynamics of particle-attached and free-living bacterial community in coastal seawater and find that microhabitats exert a stronger forcing on microbial communities than environmental variability, suggesting that particle-attachment could buffer the impacts of environmental changes and particle-associated communities likely respond to the presence of distinct eukaryotes rather than commonly-measured environmental parameters. Integrating these results will offer new perspectives on the mechanisms by which bacteria respond to seasonal temperature changes as well as potential adaptations to climate change-driven warming of the surface oceans.

Seawater carbonate chemistry and growth rate during experiments with phylotypes of Symbiodinium (Dinophyceae), 2011

We investigated the effect of elevated partial pressure of CO2 (pCO2) on the photosynthesis and growth of four phylotypes (ITS2 types A1, A13, A2, and B1) from the genus Symbiodinium, a diverse dinoflagellate group that is important, both free-living and in symbiosis, for the viability of cnidarians and is thus a potentially important model dinoflagellate group. The response of Symbiodinium to an elevated pCO2 was phylotype-specific. Phylotypes A1 and B1 were largely unaffected by a doubling in pCO2 in contrast, the growth rate of A13 and the photosynthetic capacity of A2 both increased by ~ 60%. In no case was there an effect of ocean acidification (OA) upon respiration (dark- or light-dependent) for any of the phylotypes examined. Our observations suggest that OA might preferentially select among free-living populations of Symbiodinium, with implications for future symbioses that rely on algal acquisition from the environment (i.e., horizontal transmission). Furthermore, the carbon environment within the host could differentially affect the physiology of different Symbiodinium phylotypes. The range of responses we observed also highlights that the choice of species is an important consideration in OA research and that further investigation across phylogenetic diversity, for both the direction of effect and the underlying mechanism(s) involved, is warranted.

Perspectives of Teachers Regarding the Integration of Mathematics and Science at the Secondary School Level

The integration of mathematics and science in secondary schools in the 21st century continues to be an important topic of practice and research. The purpose of my research study, which builds on studies by Frykholm and Glasson (2005) and Berlin and White (2010), is to explore the potential constraints and benefits of integrating mathematics and science in Ontario secondary schools based on the perspectives of in-service and pre-service teachers with various math and/or science backgrounds. A qualitative and quantitative research design with an exploratory approach was used. The qualitative data was collected from a sample of 12 in-service teachers with various math and/or science backgrounds recruited from two school boards in Eastern Ontario. The quantitative and some qualitative data was collected from a sample of 81 pre-service teachers from the Queen’s University Bachelor of Education (B.Ed) program. Semi-structured interviews were conducted with the in-service teachers while a survey and a focus group was conducted with the pre-service teachers. Once the data was collected, the qualitative data were abductively analyzed. For the quantitative data, descriptive and inferential statistics (one-way ANOVAs and Pearson Chi Square analyses) were calculated to examine perspectives of teachers regardless of teaching background and to compare groups of teachers based on teaching background. The findings of this study suggest that in-service and pre-service teachers have a positive attitude towards the integration of math and science and view it as valuable to student learning and success. The pre-service teachers viewed the integration as easy and did not express concerns to this integration. On the other hand, the in-service teachers highlighted concerns and challenges such as resources, scheduling, and time constraints. My results illustrate when teachers perceive it is valuable to integrate math and science and which aspects of the classroom benefit best from the integration. Furthermore, the results highlight barriers and possible solutions to better the integration of math and science. In addition to the benefits and constraints of integration, my results illustrate why some teachers may opt out of integrating math and science and the different strategies teachers have incorporated to integrate math and science in their classroom.

Concept maps as a tool to analyze the ideas of teacher training students regarding what to teach on human nutrition in Primary Education

Concept maps are a technique used to obtain a visual representation of a person's ideas about a concept or a set of related concepts. Specifically, in this paper, through a qualitative methodology, we analyze the concept maps proposed by 52 groups of teacher training students in order to find out the characteristics of the maps and the degree of adequacy of the contents with regard to the teaching of human nutrition in the 3rd cycle of primary education. The participants were enrolled in the Teacher Training Degree majoring in Primary Education, and the data collection was carried out through a training activity under the theme of what to teach about Science in Primary School? The results show that the maps are a useful tool for working in teacher education as they allow organizing, synthesizing, and communicating what students know. Moreover, through this work, it has been possible to see that future teachers have acceptable skills for representing the concepts/ideas in a concept map, although the level of adequacy of concepts/ideas about human nutrition and its relations is usually medium or low. These results are a wake-up call for teacher training, both initial and ongoing, because they shows the inability to change priorities as far as the selection of content is concerned.

Equipping young people to engage with media driven science experiences: beyond science knowledge to science literacy and discerning consumers of news.

This paper reports on a study of a curricular intervention for pupils (age 10-13 years) in the UK aimed at supporting critical engagement with science based media reports. In particular the study focused on core elements of knowledge, skills and attitudes identified in previous studies that characterize critical consumers of science presented as news. This was an empirical study based on classroom observation. Data included responses from individual pupils, in addition video recording of group activity and intentional conversations between pupils and teachers were scrutinised. Analysis focused on core tasks relating to different elements of critical reading. Pupils demonstrated a grasp of questioning and evaluating text, however the capacity to translate this experience in support of a critical response to a media report with a science component is limited in assessing the credibility of text and as an element in critical reading.

Improving Science literacy through interdisciplinary collaboration using media reported science.

The capability to respond critically to science in the news is recognised as one aspect of science literacy. Consequently, science-related news reports are an essential resource for science teachers wishing to promote critical reading as the foundation of a critical response to media reported science. Consequently Science education in schools should prepare students to engage with informal sources of science, including news media, in the world beyond formal science education. An interest in science news media is not limited to the science specialist. Science news provides an authentic context for teachers of science and English to collaborate in promoting interdisciplinary learning. The challenges of using science related news, as a context for cross-curricular collaboration, highlight the professional development needs of both science and English teachers working in this context. This qualitative study with over 150 pupils involved secondary school science and English teachers working collaboratively using media reported science resources and collated data from interviews, pre and post intervention tasks, pupils’ classwork and teacher notes. The outcomes of the project showed pupil engagement and greater capacity to carry knowledge and skills across traditional subject boundaries. Teachers reported increased understanding of the pedagogy of the alternative subject specialist and increased confidence to move outside their subject in order to facilitate pupil learning. This study would suggest that adopting an interdisciplinary approach could enhance learning for pupils and increase the confidence and capability of teachers. Additionally teachers’ engagement in professional conversations focusing on pupil progress was noteworthy.

The neurotoxin β-N-methylamino-L-alanine (BMAA) : Sources, bioaccumulation and extraction procedures

β-methylamino-L-alanine (BMAA) is a neurotoxin linked to neurodegeneration, which is manifested in the devastating human diseases amyotrophic lateral sclerosis, Alzheimer’s and Parkinson’s disease. This neurotoxin is known to be produced by almost all tested species within the cyanobacterial phylum including free living as well as the symbiotic strains. The global distribution of the BMAA producers ranges from a terrestrial ecosystem on the Island of Guam in the Pacific Ocean to an aquatic ecosystem in Northern Europe, the Baltic Sea, where annually massive surface blooms occur. BMAA had been shown to accumulate in the Baltic Sea food web, with highest levels in the bottom dwelling fish-species as well as in mollusks. One of the aims of this thesis was to test the bottom-dwelling bioaccumulation hypothesis by using a larger number of samples allowing a statistical evaluation. Hence, a large set of fish individuals from the lake Finjasjön, were caught and the BMAA concentrations in different tissues were related to the season of catching, fish gender, total weight and species. The results reveal that fish total weight and fish species were positively correlated with BMAA concentration in the fish brain. Therefore, significantly higher concentrations of BMAA in the brain were detected in plankti-benthivorous fish species and heavier (potentially older) individuals. Another goal was to investigate the potential production of BMAA by other phytoplankton organisms. Therefore, diatom cultures were investigated and confirmed to produce BMAA, even in higher concentrations than cyanobacteria. All diatom cultures studied during this thesis work were show to contain BMAA, as well as one dinoflagellate species. This might imply that the environmental spread of BMAA in aquatic ecosystems is even higher than previously thought. Earlier reports on the concentration of BMAA in different organisms have shown highly variable results and the methods used for quantification have been intensively discussed in the scientific community. In the most recent studies, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become the instrument of choice, due to its high sensitivity and selectivity. Even so, different studies show quite variable concentrations of BMAA. In this thesis, three of the most common BMAA extraction protocols were evaluated in order to find out if the extraction could be one of the sources of variability. It was found that the method involving precipitation of proteins using trichloroacetic acid gave the best performance, complying with all in-house validation criteria. However, extractions of diatom and cyanobacteria cultures with this validated method and quantified using LC-MS/MS still resulted in variable BMAA concentrations, which suggest that also biological reasons contribute to the discrepancies. The current knowledge on the environmental factors that can induce or reduce BMAA production is still limited. In cyanobacteria, production of BMAA was earlier shown to be negative correlated with nitrogen availability – both in laboratory cultures as well as in natural populations. Based on this observation, it was suggested that in unicellular non-diazotrophic cyanobacteria, BMAA might take part in nitrogen metabolism. In order to find out if BMAA has a similar role in diatoms, BMAA was added to two diatom species in culture, in concentrations corresponding to those earlier found in the diatoms. The results suggest that BMAA might induce a nitrogen starvation signal in diatoms, as was earlier observed in cyanobacteria. However, diatoms recover shortly by the extracellular presence of excreted ammonia. Thus, also in diatoms, BMAA might be involved in the nitrogen balance in the cell.

Democratic Citizenship - A Conditioned Apprenticeship : A Call for Destabilisation of Democracy in Education

We live in times when the search for a citizenship education that can transcend national, ethnical and cultural borders is an important part of educational policy. In times of increased pressure by the European Union on its nation states to provide for nation-transcending democracy, this question becomes crucial for national policymaking in Europe. In this text, Swedish education policy will be taken as a case in point in order to shed light on how this question is being handled in this particular national policy setting. It is argued that the policy’s citizen fostering agenda tends to be counterproductive in the sense that it is still situated in national notions of the relationship between democracy and education, which tend to exclude certain individuals and groups of people on an age-related and (ethno) cultural basis. It is further argued that these excluding features can be related to educational ideas about socialisation. The aim of this text is underlined by suggesting a different way of framing democracy and democratic citizenship education: to increase the potential of education as regards the renewal of democracy and democratic citizenship.

Learning from Text: Examining Teacher Thinking and Practice in AP Environmental Science

Thesis (Ph.D.)--University of Washington, 2016-08

"It’s just very natural" – interpersonal knowledge as a didactical device in guided classroom conversations in religious education

This article investigates how teachers in religious education (RE) think and act as professionals while working with differences in religious and philosophy of life experiences and beliefs in class and trying to do this in respectful and inclusive ways. It analyses data from two research projects that were carried out in lower secondary school in Norway. The main research question is: What is the relationship between teachers’ contextual knowledge and knowledge of the child and how do these two dimensions of professional knowledge interact when religious education teachers try to strike a good balance between inclusion and productive learning in their teaching practice? The data analysed were drawn from three different data sets featuring three Norwegian religious education-teachers. The research was part of the EU-funded "REDCo"-project and the "Religious education and diversity" - project ["ROM"] funded by the Norwegian Research Council. The interviewees emphasized the potential of the religious education subject to contribute to a wider tolerance for difference and to support individual students in their identity management. The analysis shows, however, that considerable contextual awareness - of the classroom and of the local community - is needed to realize this potential. It also shows the importance of interpersonal knowledge between the teacher and each student if contextual awareness is to be effective in terms of inclusion, participation, wellbeing and good learning outcomes for all students.

Conditions for Teaching and Learning in Religious Education (RE) : Perspectives of Teachers and Pupils at the Beginning of the 6th Grade in Sweden

In this article empirical findings from interviews with teachers of three classes of 12-year-old pupils are presented, together with questionnaire-responses from these 54 pupils. The interviews focus on teaching aims for Religious Education (RE), a subject that in Sweden, besides dealing with religion, also explores other kinds of beliefs, ethics and life questions. In the questionnaire the pupils are asked to solve four RE tasks with content that is central from a Swedish curriculum perspective. The research involves pupils at the beginning of the sixth grade and the purpose of this article is to look at the teachers’ aims and the pupils’ responses, and consider what these may indicate about conditions for teaching and learning RE in these classes. The findings show that the perspectives of the pupils at the beginning of the sixth grade seem to be rather far from the expectations of the RE syllabus. The pupils’ statements are rather vague with regard to religion as a phenomenon and there are few examples of pupils interpreting religious symbols in a way that is useful in further analysis. While existential and ethical plots, messages and point of views are comparatively easy to describe, it is harder to express multiple perspectives, reasons, comparisons and questions. A problem for the teachers in developing the perspectives of their pupils is that they find it hard to say what kind of general difficulties pupils have in RE, a fact that makes it hard to direct the teaching. Another challenge is that the teachers’ RE-aims are rather overarching and primarily related to fostering fundamental values. What improves the conditions for teaching and learning is the teachers’ concern for the pupils and their relationships with the teacher and with each other, a factor which is of vital importance for learning and which can also be used as a specific teaching method in subject matter education.

Citizenship education, national identity and political trust: The case of Sweden

The challenging effects of globalization upon the nation-state have been a recurrent theme in the social science discourse since the 1990’s. Nationally organized education is also seen as challenged by new demands originating from globalization. In this article it is argued that ‘nation-state’ and ‘national identity’ are highly relevant concepts when discussing a citizenship education that seeks to develop a civic ethos with, potentially, a global reach. It is further argued that the understanding of such an ethos would benefit significantly from incorporating the role of political trust since trust has been identified as a main feature of the social capital that makes democracy work. Three themes are brought together: national identity and identification, the importance for democracy of political trust and the challenges citizenship education face when carried out in a national context but intended to manage issues that go far beyond the reach of the nation-state. The importance of citizenship education is discussed using recent research on the Swedish citizenship education classroom.

Effects of a 12-week aerobic exercise intervention on eating behaviour, food cravings and 7-day energy intake and energy expenditure in inactive men

This study examined effects of 12 weeks of moderate-intensity aerobic exercise on eating behaviour, food cravings and weekly energy intake and expenditure in inactive men. Eleven healthy men (mean ± SD: age, 26 ± 5 years; body mass index, 24.6 ± 3.8 kg/m2; maximum oxygen uptake, 43.1 ± 7.4 mL/kg/min) completed the 12-week supervised exercise programme. Body composition, health markers (e.g. blood pressure), eating behaviour, food cravings and weekly energy intake and expenditure were assessed before and after the exercise intervention. There were no intervention effects on weekly free-living energy intake (p=0.326, d=-0.12) and expenditure (p=0.799, d=0.04), or uncontrolled eating and emotional eating scores (p>0.05). However, there was a trend with a medium effect size (p=0.058, d=0.68) for cognitive restraint to be greater after the exercise intervention. Total food cravings (p=0.009, d=-1.19) and specific cravings of high-fat foods (p=0.023, d=-0.90), fast-food fats (p=0.009, d=-0.71) and carbohydrates/starches (p=0.009, d=-0.56) decreased from baseline to 12 weeks. Moreover, there was a trend with a large effect size for cravings of sweets (p=0.052, d=-0.86) to be lower after the exercise intervention. In summary, 12 weeks of moderate-intensity aerobic exercise reduced food cravings and increased cognitive restraint, however, these were not accompanied by changes in other eating behaviours and weekly energy intake and expenditure. The results indicate the importance of exercising for health improvements even when reductions in body mass are modest.

Sexting na adolescência: análise da rede de enunciações produzida pela mídia

Esta tese foi produzida no Programa de Pós -Graduação em Educação em Ciências : Química da Vida e Saúde , na linha de pesquisa "Educação científica : implicações das práticas científicas na constituição dos sujeitos ". O objetivo desta pesquisa é analisar a rede de enunciações sobre o sexting em alguns materiais (reportagens, programas televisivos, postagens em blogs e comentários realizados por leitores dos sites) presentes na internet e investigar as condições de emergência da prática do sexting. O sexting é um termo criado nos Estados Unidos da América, que deriva das expressões sex (sexo) e texting (envio de mensagens). Esse conceito descreve uma prática social e cultural que está sendo difundida mundialmente: esta consiste em produzir e enviar fotos e vídeos sexuais, sensuais e eróticos entre conhecidos/as, amigos/as, namorados/as, “ficantes” etc.. Nesta pesquisa, utilizamos como aporte teórico os estudos de Pierre Lévy, André Lemos, Paula Sibilia, Guy Debord, Hannah Arendt, Michel Foucault e Zygmunt Bauman. Tais autores ajudam-nos a pensar que o sexting emerge devido a alguns acontecimentos sociais, culturais, históricos etc., que vêm provocando alguns deslocamentos em nossa sociedade. Para proceder com tal pesquisa, utilizamos a internet como campo empírico. Em nossa busca, encontramos 48 artefatos culturais que discutem, de alguma forma, sobre sexting. Dentre estes, 37 comentam sobre vídeos caseiros que mostram relações sexuais, 8 discutem sobre o fenômeno sexting e 3 debatem sobre a produção de fotos sensuais. Para análise dos dados, utilizamos algumas ferramentas foucaultianas, especialmente os conceitos de discurso, dispositivo e enunciado. Ao olharmos os materiais, percebemos que os/os adolescentes vêm se utilizando das tecnologias digitais para visibilizarem a sua sexualidade, o que nos dá indícios de que estas vêm possibilitando a constituição de jornalistas cidadãos/ãs. Além disso, evidenciamos que as fotos e vídeos dos/as adolescentes foram produzidos em comum acordo entre eles/as. Muitos dessas fotos e vídeos, foram disseminados pelos próprios sujeitos que aderiram a essa prática. Assim, a exposição da sexualidade, por meio do sexting, tem sido realizada com o propósito de adquirir visibilidade e de tornar-se a personalidade do momento. Entendemos que essa vontade de escancarar a sexualidade, por meio das tecnologias digitais, está vinculada à sociedade do espetáculo, que manifesta a necessidade de tornar-se visível. Além disso, notamos que essa prática está relacionada à escola, pois muitos dos casos relatados ocorreram no interior dessa instituição ou tiveram uma repercussão nesse ambiente. Em muitos casos, a escola era culpabilizada pelos casos de sexting que envolviam seus/sua alunos/as. No entanto, são os pais o foco de maiores críticas pela mídia massiva, pois, para essa instância, são estes os maiores responsáveis pela disciplinarização desses corpos. Evidenciou-se também que os/as praticantes do sexting sofreram micropenalidades, as quais tinham como objetivo corrigir suas condutas. Nesse sentido, entendemos o sexting como uma atualização do dispositivo da sexualidade, pois este coloca a sexualidade – a qual, durante a modernidade sólida, constituía-se como algo exclusivamente do âmbito privado – em evidência nos espaços públicos. Ao mesmo tempo, verificamos que algumas práticas disciplinares ainda buscam governar e normalizar a sexualidade dos sujeitos. A análise do material empírico possibilitou-nos verificar dois enunciados que fazem parte do discurso do sexting. O primeiro destes é que, na contemporaneidade, aparecer é uma condição de existência; o outro é que a sexualidade é entendida como algo que deve ser regulado, governado e normalizado. Consideramos importante centrarmos os estudos no sexting, pois entendemos que essa prática vem contribuindo para o surgimento de outros modos de viver e entender a sexualidade, pois o sexting enquadra a sexualidade como algo a ser exibido e mostrado para todos/as.